October 13-17, 2008 43

October 15 [Wednesday] Grand Ballroom B

Poster Poster Poster Poster Poster Poster Poster Poster Poster Poster Poster Poster Poster Poster Poster SessionSessionSessionSessionSessionSessionSessionSessionSessionSessionSessionSessionSessionSessionSessionPoster Session

P-1

A New Voltage Driving Method for Large Size and High Resolution AMOLED Displays with a-Si:H Backplane.S. H. Yu, Y. J. Hong, J. D. Lee, H. S. Kim, S. J. Lee, and Y. H. Tak (LG Display Co., Ltd., Korea)We propose a novel n-type a-Si:H TFT pixel circuit which is proper to AMOLED display for the large size and high resolution. Proposed pixel circuit will be suit to panel for the high resolution because of different threshold sampling method. …

P-2

A New I-V Equation for Thin Film Transistors and Its Parameter Extraction MethodK.-D. Jung, Y. C. Kim, B.-G. Park, H. Shin, and J. D. Lee (Seoul Nat′l Univ., Korea)Based on the device physics, a new I-V equation for TFTs is derived and a simple parameter extraction method is suggested. The new method gives more physically meaningful threshold voltage and mobility, and the obtained values can be directly used for the TFT device modeling.

P-3

New Process Development for Hybrid Silicon Thin Film TransistorS. H. Cho, Y. M. Choi, Y. G. Jeong, H. Kim, S.-H. Yang, J. H. Song, C.-O. Jeong, and S. Y. Kim (Samsung Electronics Co., Ltd., Korea)The new process for hybrid silicon thin film transistor (TFT) using DPSS laser has been developed for realizing both low-temperature poly-Si (LTPS) TFT and a-Si:H TFT on the same substrate as a backplane of active matrix liquid crystal display. LTPS TFTs are integrated on the peripheral area of the panel for gate driver integrated circuit and a-Si:H TFTs are used as a switching device for pixel in the active area. …

P-4

A Novel Pixel Structure for High Transmission TFT-LCDK.-J. Shin, S.-Y. Song, I.-P. Lee, C.-H. Kim, C.-S. Jang, C.-C. Chai, and J.-H. Souk (Samsung Electronics Co., Ltd., Korea)We have developed a LCD Panel that form storage capacitance for pixels between pixel electrode of bottom glass and common electrode of top glass. This method could make higher transmission and higher production yield than before by removing storage electrode line and capacitance on the bottom glass by simplifying bottom pixel structure.

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P-5

Effect of Hafnium Oxide on ALD Grown ZnO Thin Film TransistorW.-S. Choi (Hoseo Univ., Korea)The TFTs from ZnO semiconductor with hafnium oxide dielectrics were prepared by atomic layer deposition to characterize the electrical properties. Good electrical properties of oxide TFT was obtained with channel mobility of 2.1 cm2/Vs, threshold voltage of 0 V, the subthreshold slope of 0.9 V/dec, and on to off current ratio of 106.

P-6

Ultra-slim LCD TV Module using Edge-lit LED Backlight SystemW. J. Kim, J.-W. Cho, D.-M. Yeo, B.-D Ye, D. Seo, J. Choi, and T. Jang (Samsung Electronics Co. Ltd., Korea)We present an ultra-slim LCD module for 40-inch FHD TV. By employing edge-lit backlight system, module thickness of 10mm is achieved. To satisfy the luminance spec of 450 nits in FHD resolution, it is critical to adopt high efficient LED and optical components.

P-7

Bottom Gate Microcrystalline Silicon TFT Fabricated on Plasma Treated Silicon NitrideJ.-J. Huang, Y.-P. Chen, H.-C. Lin, H.-C. Yao, and C.-C. Lee (ITRI, Taiwan)Bottom-gate microcrystalline silicon thin film transistors (µc-Si:H TFTs) were fabricated on glass and transparent polyimide substrates by conventional 13.56 MHz RF plasma enhanced chemical vapor deposition at 200 . The deposition rate of the µc-Si:H film is 24 nm/min and the amorphous incubation layer near the µc-Si:H/silicon nitride interface is unobvious. The threshold voltage of µc-Si:H TFTs can be improved by H2 or NH3 plasma pretreatment silicon nitride film.

P-8

Dry Etching Process for the Fabrication of Transparent InGaZnO TFTsS. M. Yoon, W. S. Cheong, C. S. Hwang, S. H. Park, D. H. Cho, J. H. Shin, M. Ryu, C. W. Byun, S. Yang, J. I. Lee, S. M. Chung, H. Y. Chu, and K. I. Cho (ETRI, Korea)We proposed the dry etching process recipe for the fabrication of In-Ga-Zn-O (IGZO)-based oxide TFTs, in which the etching behaviors of IGZO films were systematically investigated when the etching gas mixtures and their mixing ratios were varied. Good device characteristics of the fabricated TFT were successfully confirmed.

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P-9

Degradation Study of Organic TFTs under UV Irradiation StressJ.-Y. Yan, K.-P. Liao, J.-L. Liao, L.-H. Chen, M.-R. Lin, T.-W. Lee, S.-T. Yeh, K.-Y. Cheng, Y.-Y. Wu, C.-H. Yu, Y.-Y. Lee, and J.-C. Ho (ITRI, Taiwan)Pentacene based TFT showed a degraded mobility and saturation current (Ion) after exposure to the high energy ultraviolet (UV). In this article, we optimize the thickness of UV resisted layer on OTFT to restrain the degradation from protect layer deposition and study the UV aging effect of pentacene based TFT. The OTFT deivce with UV resisted layer could keep over 50% mobility after suffered UV 103J.

P-10

Response Characteristics for Low Voltage Liquid Crystal Display Employing a Constant Charge ModelM.-S. Kim, S.-J. Huh, D.-J. Suh, Y.-J. Ahn, K.-J. Lee, S.-H. Ahn, K.-H. Kim, and S.-S. Kim (Samsung Electronics Co., Ltd., Korea)The response time characteristic of low voltage liquid crystals (LCs) is investigated and a new simulator for low voltage LCs is proposed. In order to enable low voltage operation, it is important to minimize Vth of LCs and variation of pixel voltage caused by dynamic capacitance operation of LC Display. Because dynamic capacitance variation is much larger for low voltage LC operation compared to that of conventional LC material, it is necessary to make a better model for dynamic …

P-11

3-D FEM Study on the Optical Characteristics of S-IPS ModeS. S. Yang, S. Y. Park, and T. Won (Inha Univ., Korea)In this paper, we propose a novel electrode structure for superb transmittance in super in-plane switching (S-IPS) mode while keeping the features of the conventional SIPS mode such as the capability of initial LC alignment. The optimization of the electrode made it possible to enhance the light transmittance approximately by 14 % in comparison to the conventional S- IPS cell.

P-12

The Improvement of Display Brightness in LCD-TV Panel through the Optimization of Organic Passivation ProcessY. B. Lee, H. Lee, S. Kim, and S. S. Kim (Samsung Electronics Co., Ltd., Korea)We report the improvement in brightness through the optimization of the organic passivation process for fabricating a TFT substrate for LCD-TV panel. In conclusion, the optimization of organic passivation was accomplished with improving over 10 cd/m2 in brightness than that of a conventional organic passivation process.

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P-13

Hot Carrier Reliability of Short Channel (L=1.5µm) P-type Low Temperature Poly-Si TFTS.-H. Choi, H.-S. Shin, W.-K. Lee, S.-H. Kuk, and M.-K. Han (Seoul Nat′l Univ., Korea)We have investigated the reliability of short channel (L=1.5µm) p-type ELA poly-Si TFTs under hot carrier stress. Threshold voltage of short channel TFT was significantly more shifted to positive direction than that of long channel TFT under the same stress. This result may be attributed to electron trapping at the interface between poly-Si film and gate oxide layer.

P-14

Fabrication of Roll Printed Organic Thin-film Transistors using Patterned Polymer StampJ. Jo, J.-S. Yu, D.-S. Kim, K.-Y. Kim, and E.-S. Lee (KIMM, Korea)Roll-printed organic thin-film transistors (OTFTs) were fabricated by gravure or flexography printing using patterned PDMS stamp with various channel lengths, silver pastes, coated polyvinylphenol dielectric, and jetted bis(triisopropyl-silylethynyl) pentacene semiconductor on plastic substrates. The roll-printed OTFT parameters were obtained: fieldeffect mobility of 0.1 cm2/Vs, an on/off current ratio of 104 and a subthreshold slope of 2.53 V/decade.

P-15

Stability of Low Temperature a-Si:H TFT on Stainless Steel SubstrateS. H. Kim, S. S. Kim, Y. I. Park, S. H. Peak, K. M. Lee, C. H. Park, Y. S. Lim, C.-D. Kim, and I. B. Kang (LG Display Co., Ltd., Korea)Low Temperature a-Si:H TFT on stainless steel substrate has been developed for the flexible electrophoretic display. Stability of low temperature a-Si:H TFT is more important point than its initial device characteristics. Thus, we have studied device characteristics of low temperature a-Si:H TFT in terms of stability for driving electrophoretic display.

P-16

An Internal Touch Screen Panel using Standard a-Si:H TFT LCD ProcessB. H. You, B. J. Lee, K. C. Lee, S. Y. Han, J. H. Koh, S. Takahashi, B. H. Berkeley, N. D. Kim, and S. S. Kim (Samsung Electronics Co., Ltd., Korea)A touch screen panel embedded 12.1-inch TFT LCD employing a standard a-Si:H TFT process has been successfully developed. Compared with conventional external touch screen panels, the new internal TSP exhibits a clearer image and improved touch feeling. Our new internal proposed TSP can be fabricated with low cost.

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P-17

Effect of Deposition Method of Source/drain Electrode on a Top Gate ZnO TFT PerformanceS.-H. Park, C.-S. Hwang, and S. Yang (ETRI, Korea), Y. S. Yun, and B. C. Park (Pla-works, Korea)We have investigated the effect of source/drain electrode deposition method on a performance of top gate structured ZnO TFT performance. TFT using S/D of ITO film, consisted of bi-layer which deposited by ion beam assisted sputtering at the initial stage then deposited by DC magnetron sputtering, showed better performance compared to that using S/D of ITO deposited by just DC magnetron sputtering. Two ITO films exhibited different grain shapes and these resulted in different etching properties. We also suspect that charge trapping on the glass substrate (back channel) during the ITO film deposition may influence the characteristics of top gate structured ZnO TFT.

P-18

Narrow Channel Formation using Asymmetric Halftone Exposure with Conventional PhotolithographyK.-C. Cheon, J.-H. Woo, D.-S. Jung, M. Park, H. Kim, B.-H. Lim, and S.-J. Yu (LG Display Co., Ltd., Korea)Developed halftone exposure technique was successfully applied to the fabrication of narrow transistor channels below 4 with conventional photolithography method. Asymmetric slits concept of photo mask was applied to make channel lengths (L) shorter for thin film transistor’s (TFT) high performance. These short channel TFTs verified better quality transistor characteristics.

P-19

Direct Deposition of High Quality Nanocrystalline Silicon Films by Catalytic CVD at Low Temperatures (200 )T.-H. Kim, K.-M. Lee, J. Hwang, and W.-S. Hong (Univ. of Seoul, Korea)We attempted modulation of the hydrogen dilution ratio in a Cat-CVD system to achieve both the minimal incubation layer and the high throughput. We obtained the incubation layer thickness of 3 nm, and were able to grow a 200 nm-thick film having a 70 % crystallinity in 18 minutes.

P-20

Reverse Annealing of Boron Doped Polycrystalline SiliconJ.-Y. Lim, W.-E. Hong (Hongik Univ., Korea), D. H. Kim, T. Uemoto, C. W. Kim (Samsung Electronics Co., Ltd., Korea), and J.-S. Ro (Hongik Univ., Korea)Through-doping conditions with higher energies and doses were intentionally chosen to understand reverse annealing behavior. We observed that the implantation condition plays a critical role on dopant activation. We found a certain implantation condition with which the sheet resistance is not changed at all upon activation annealing.

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P-21

Physical Effect of Annealing Conditions on Soluble Organic Semiconductor for Organic Thin Film TransistorsD. Kim, D. Kim, K. Kim, H. Kim, D. Lee, and M. Hong (Korea Univ., Korea)We have examined the effect of physical drying and annealing conditions for the soluble derivatives of polythiophene as p-type channel materials of organic thin film transistors (OTFTs) in our special designed drying system; performances of the jetting-processed OTFTs can be improved more than 10 times just by optimizing the physical conditions of drying and annealing.

P-22

Improvement of Source-drain Contact Properties of Organic Thin-film Transistors by Metal Oxide and Molybdenum Double LayerK. Kim, D. Kim, D. Kim, H. Kim, D. Lee, and M. Hong (Korea Univ., Korea)The contact resistance between organic semiconductor and source-drain electrode in Bottom Contact Organic Thin-Film Transistors (BCOTFTs) can be effectively reduced by metal oxide/molybdenum double layer structure; metal oxide layers including nickel oxide (NiOx/Mo) and moly oxide(MoOx) under molybdenum work as a high performance carrier injection layer. Step profiles of source-drain electrode can be easily achieved by simultaneous etching of the double layers using the difference etching rate between metal oxides and metal layers.

P-23

Optimal Electrode Design for In Plane Switching (IPS) CellS. S. Yang, S. Y. Park, and T. Won (Inha Univ., Korea)In this paper, we propose a novel electrode structure for In Plane Switching (IPS) mode LC cell which provides the enhanced transmittance and wider viewing angle as well as less color shift. The simulation results revealed that transmission increases by more than 11.9% and shows less color shift than the conventional S-IPS mode.

P-24

Air Stable n-type Organic Field Effect Transistors using a Perfluoropolymer InsulatorJ. Jang, J. W. Kim, N. Park, and J.-J. Kim (Seoul Nat′l Univ., Korea)Air stable n-type organic field effect transistors (OFETs) based on CB60B are realized using a perfluoropolymer as the gate dielectric layer. The devices showed the field-effect mobility of 0.05 cmP2 P/Vs in ambient air. Replacing the gate dielectric material by SiOB2B resulted in no transistor action in ambient air. Perfluorinated gate dielectric layer reduces interface traps significantly for the n-type semiconductor even inambient air

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P-25

Driving Methods of LCD-TV using a-Si:H TFT Integrated Gate DriversC.-S. Lee, M.-C. Lee, Y.-S. Lee, Y.-H. Bae, Y.-S. Kim, S.-H. Moon, N.-D. Kim, and S.-S. Kim (Samsung Electronics Co., Ltd., Korea)LCD-TV applications were successfully implemented using integrated gate drivers. Integrated gate drivers have been implemented on a HD panel for 60Hz operation and on a FHD panel for 120Hz operation. It is found that the integrated gate driver reduces the flicker of a panel.

P-26

Single Mode Transflective Liquid Crystal Display based on Single Cell Gap without Sub-pixel SeparationT. Du, H. Y. Mak, P. Xu, V. Chigrinov, and H. S. Kwok (Hong Kong Univ. of Science and Tech., Hong Kong)

P-27

Advanced Cell Structure for High Contrast Ratio in Charge Share S-PVA MonitorsS. J. Kim, K.-H. Kim, J. Jung, J.-U. Heo, N.-S. Lee, K.-H. Kim, and S. S. Kim (Samsung Electronics Co., Ltd., Korea)This paper describes a new S-PVA cell structure which achieves enhanced contrast ratio by adopting a step-like patterned common electrode between the high sub-pixel and low sub-pixel electrodes without loss of transmittance. A 24-inch panel was developed for monitor applications and measured contrast ratio and white luminance were over 2500:1 and 400cd/m2, respectively.

P-28

Reflective Twist Nematic Liquid Crystal Display For High ReflectanceO.-S. Son, Y.-I. Park, D.-H. Beak, G. Son, and D.-H. Suh (Hydis Tech. Co., Ltd., Korea)We have developed new reflective LCD for Mixed twist nematic LC mode with high quality image. We have foung out an optimal twist angle of LC and optical film′s axis by simulation. Also we measured electro-optic characteristics for new design ganel. As a result, high relectance and wide viewing angle characteristics were achieved.

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P-29

Novel PVA Pixel Design for Mobile Application with Excellent Off-axis Image QualityJ. H. Kim, G. B. Kim, J. Y. Choi, Y.-K. Jang, S. H. Ahn, K.-H. Kim, and S. S. Kim (Samsung Electronics Co., Ltd., Korea)We developed a novel PVA pixel design for mobile application with excellent off-axis image quality and optical performance by introducing Active Level Shift technology and optimizing pixel structure. Our new pixel design enables better off-axis image quality without sacrificing other optical properties compared with a conventional mPVA structure.

P-30

A New Evaluation Method for LCD Panel Anti-smudge TreatmentK.-J. Lee, S.-J. Huh, D.-J. Suh, S.-H. Ahn, K.-H. Kim, and S.-S. Kim (Samsung Electronics Co., Ltd., Korea)We suggest a new method to evaluate the anti-smudge performance of LCD panels. The anti-smudge performance is characterized by oleic acid contact angle. This method shows accurate and reproducible result and overcomes the difficulty of quantitative evaluation for the anti-smudge characteristic and low reliability in several proposed measurements.

P-31

Touch Screen Panel by using Liquid Crystal Capacitance Variation Embedded in LTPS AMLCDW. Lee, T.-J. Ha, H.-S. Park, J.-S. Lee, and M.-K. Han (Seoul Nat′l Univ., Korea)We present a new touch screen method, which utilizes the variation of liquid crystal capacitance according to the touch event on the screen. It is integrated in the AMLCD with the conventional LTPS process. Its resolution is same as the display resolution as well as performs the multi-touch sensing function basically. The design concept and the operation are verified with the SPICE simulation.

P-32

High Performance Azimuthally Continuous Nematic Domain Mode for TFT-LCD ApplicationK.-S. Bae, J. S. Gwag, I.-Y. Han, Y.-J. Lee, M. Y. Jin, and J.-H. Kim (Hanyang Univ., Korea)We proposed azimuthally continuous nematic domain mode characterized by a cone feld induced from patterned electrode structure with a circular slit. This mode has good optical performances such as higher transmittance and wider viewing angle through decreasing the demerits caused by domain walls. We could confirm to these optical characteristics by the manufactured sample.

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P-33

Surface Sliding Effect of Nematic Liquid Crystals on Soft- polymerC.-H. Lee, J. S. Gwag, Y. J. Lee, M. Y. Jin, and J.-H. Kim (Hanyang Univ., Korea)Recently, study on the weak interaction energy between the soft polymer surface and liquid crystals has been a primary topic for new LC device applications. In this paper, to understand the switching property of nematic liquid crystals (LCs) at the interface with a weak anchoring boundary, we investigate experimentally the rotation property of surface nematic director by electric field on non-treated Poly-Methylmethacrylate (PMMA, Tg=110°C, Sigma Aldrich) film observed under various temperatures including the glass transition temperature (Tg) of the polymer layer.

P-34

Control of Surface Anisotropy by Exposing Linearly Polarized Ultraviolet LightK.-N. Kim and J.-H. Kim (Hanyang Univ., Korea)We examine the surface alignment of liquid crystals (LC’s) by a double linearly polarized ultraviolet (LPUV) light expose process. Exposing polarized light induces a surface anisotropy to polyimide (PI) layer surfaces and hence determines the alignment direction. LPUV exposes with angular difference of 45° between two polarization directions make LC director change.

P-35

Enhancement of Pretilt Angle using Blending PolyimideS.-G. Lee, S. E. Shin (Hongik Univ., Korea), K. Y. Choi, M.-H. Yi (KRICT, Korea), and D. M. Shin (Hongik Univ., Korea)Photo-alignment layer which contains cinnamate is difficult to generate pretilt angle of liquid crystals. In order to enhance pretilt angle, blending poly (amic acid) between containing fluorine poly (amic acid) and 1,2,3,4-cyclobutanetetracaroxylic dianhydride (CBDA) / 3,5-diaminobenzyl alcohol (DBA) were used. For photoreaction, cinnamate was conjugated by interfacial reaction with blending polyimide

P-36

Temperature Dependent Electro-optical Studies of Liquid Crystal in Fringe Field Switching (FFS), In-plane Switching (IPS), and Patterned Vertical Alignment (PVA) ModesE. M. Jo, A. K. Srivastava, M. Kim, S. M. Kim, S. H. Lee (Chonbuk Nat′l Univ., Korea), S. H. Ji, and G.-D Lee (Dong-A Univ., Korea)In this paper, electro-optical characteristic of Nematic Liquid crystal (LC) with varying temperature in different LCD modes, namely Fringe Field Switching (FFS), In-plane switching (IPS), and Patterned Vertical Alignment (PVA) modes are investigated and compared. Electro optic measurements suggest that rate of change of transmission with temperature in FFS mode was lowest and much more thermally stable as …

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P-37

Synthesis and Biaxial Nematic Properties of Novel Liquid Crystalline X-shaped Mesogens Containing Perfluoroalkyl Alkanes as a Side ChainB.-H. Lee, E.-J. Choi (Kumoh Nat′l Inst. of Tech., Korea), S.-B. Park, W.-C. Zin (POSTECH, Korea), G. S. Lee, and T.-H. Yoon (Pusan Nat′l Univ., Korea)Novel X-shaped molecules containing perfluoroalkyl alkanes as a side chain have been synthesized and characterized. The properties of mesophases were investigated by a combination of differential scanning calorimetry (DSC), polarizing optical microscopy (POM), X-ray diffractometry (XRD) and electro-optical measurements.

P-38

Study on Electro-optic Characteristics in the Optically Compensated Splay Cell with UV-curable Reactive MesogenS. S. Kim, E. J. Jeon, M.-H. Lee, and S. H. Lee (Chonbuk Nat′l Univ., Korea)We have studied the optically compensated splay (OCS) mode using reactive mesogen monomer to reduce critical voltage, setting voltage and phase transition time from initial bend to splay state. The high pretilt angle from vertical alignment was formed through the polymerization of UV curable RM monomer at the surfaces. In this way, orientation of the LC with OCS can be achieved without setting voltage.

P-39

Biaxial Nematic Phase Derived From Banana-shaped Molecules Containing Naphthylene Central UnitY.-H. Seo, E.-J. Choi (Kumoh Nat′l Inst. of Tech., Korea), S.-B. Park, and W.-C. Zin (POSTECH, Korea)Banana-shaped molecules were synthesized introducing ester linking group into mesogenic unit, varying the central unit with 1,6-, 2,3-naphthylenes, and introducing the hexyloxy group as the terminal flexible unit. The properties of the compounds were characterized by FT-IR, NMR spectroscopy, DSC, polarizing optical microscopy, and X-ray diffractometry.

P-40

A Superior Optical Performance of Advanced S-IPS LCDs with Fine Pitch Electrode and Robust DesignJ.-U. Kwon, S. W. Lee, I. K. Jung, H. D. Han, I. C. Park, K. H. Lee, H. M. Moon, and H. H. Shin (LG Display Co., Ltd., Korea)We have studied on optical properties of advanced S-IPS with a fine pitch electrode and a new finger design. Transmittance of panel increases with decreasing of width and angle of finger electrode. In order to improve transmittance, fine pitch electrode of ~2µm and rubbing angle of 10 degree have been adopted. Various optical performances are defined as the function of finger design and field intensify across the IPS pixel electrodes. …

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P-41

Low Power Consumption in Twisted Nematic Mode using Novel Liquid Crystal MixtureS. Y. Jeon, I. B. Song, S. H. Hong, D. J. Lee, H. C. Choi, and M. H. Park (LG Display Co., Ltd., Korea)Recently, Note PCs have being widely used due to their features such as good mobility and low power consumption. In order to ensure the current market position, further improvement is required. Especially, the lower operating voltage is essential for the long operating time of Note PCs. For the achievement of lower operating voltage, possible contributions from LC materials side are to lower the viscosity and to increase the dielectric constant without sacrificing the reliability. …

P-42

Transflective Liquid Crystal Display with Single Cell Gap and Simple StructureM. Kim, Y. J. Lim, E. Jeong, M. H. Chin, J. H. Kim, A. K. Srivastava, and S. H. Lee (Chonbuk Nat′l Univ., Korea)This work reports the simple fabrication of the single cell gap transflective liquid crystal display (LCD) using wire grid polarizer. The nano sized wire grid polarizer was patterned on common electrode itself, on the reflective part of FFS (Fringe field switching) mode whereas the common electrode was unpatterned at transmissive part. However, this structure didn’t show single gamma curve, so we further improved the device by patterning the common electrode at transmissive part. As a result, V-T curve of proposed structure shows single gamma curve. …

P-43

Fabrication of the Outer Type-dynamic Microlens Array using Surface-stabilized Ferroelectric Liquid CrystalY. W. Kim, J. S. Gwag, K.-B. Kim, T.-H. Kang, and J.-H. Kim (Hanyang Univ., Korea)We fabricated the outer type-dynamic microlens array using a surface- stabilized ferroelectric liquid crystal, UV curable polymer and the stacked liquid crystalline polymer. The outer type-microlens array has a lower driving voltage and fast switching property. It is applicable to a variety of optical systems.

P-44

Viewing Angle Controllable LCD by Thermal Modulation of Optical LayerI. Y. Han, J. S. Gwag, Y. J. Lee, and J.-H. Kim (Hanyang Univ., Korea)We suggest a viewing angle control mode of liquid crystal display(LCD) with additive thermal controllable optical layer [TCIL], which composed of homeotropically or homogenously well digned LC layer and patterned heating lines on a substrate. In this system, LCD modes with wide viewing angle characteristics can be used as a main panel.

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P-45

Development of TFT-LCD Panel with Reduced Driver ICsS.-M. Kim, J.-H. Lee, H.-W. Lee, J.-H. Lee, and K.-S. Choi (Samsung Electronics Co., Ltd., Korea)A 15.4” WXGA TFT-LCD, featuring integrated a-Si:H gate driver circuits and reduced data driver ICs, has been developed. To reduce number of data lines into 1/2 of conventional structure, the pixel array has been re-mapped with re-organized data signal. Unintended artificial effects such as flicker were removed by adopting the novel pixel array having a ‘zigzag’ map. …

P-46

Address Discharge Delay Reduction in AC PDP by Applying MgO Nanoparticle under Protective LayerK.-H. Seo (Samsung SDI, Korea), S. H. Shin, M. S. Choi, and K.-W. Whang (Seoul Nat′l Univ., Korea)We report a method for improving characteristics of AC PDP in this study. This improvement is obtained by spreading MgO nanoparticles on transparent dielectric layer. These nanoparticles are covered with MgO protective layer by electron beam evaporation. MgO nanoparticle has difference in cathodoluminescence stronger than MgO layer by electron beam evaporation. This method worked for reducing statistical delay especially. Efficacy, discharge voltage and luminance were also improved. But these improvements has limited lifetime because continuous ion bombardments changed characteristic of MgO surface.

P-47

The Structure and Properties of 50SnO2-(50-x)P2O5-xB2O3 for Component Materials of PDPY.-T. An (Inha Univ., Korea), B.-H. Choi, M.-J. Ji , Y.-S. Ko (KICET, Korea), and H.-S. Kim (Inha Univ., Korea)Glasses in the SnO2-(50-x)P2O5-xB2O3 system were examined as potential replacement for the PbO glass frits with low firing temperature for com-ponent materials of a plasma display panel. The glasses were evaluated for their structural and the thermal expansion coefficient, glass transition and glass softening temperatures and Vickers hardness as a function of the B2O3 content.

P-48

Preparation of MgO Thin Film by Neutral-beam-assisted Deposition as a Protective Layer of AC PDPZ.-H. Li. and S. J. Kwon (Kyungwon Univ., Korea)In this experiment, MgO thin films were deposited by oxygen neutral beam assisted deposition (NBAD) method. The results show that neutral beam energy plays an important role in the surface morphology, crystal orientation, defects of MgO thin films, and discharge characteristics of AC PDP

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P-49

Discharge Characteristics of Low Xe and High Xe Content in He-Ne-Xe Gas Mixture in PDPO. Kwon, H. S. Bae, and K.-W. Whang (Seoul Nat′l Univ., Korea)The discharge characteristics of He-Ne-Xe gas mixture with the variation of Xe content are investigated through the numerical simulation. VUV efficacy in the gas condition of low Xe content increases due to more excitation and the case of high Xe content shows the improvement of VUV efficacy with the increase of He content but decreased VUV efficacy after tthe He mixing ratio of He and Ne is 0.5 due to frequent ionization.

P-50

Formation of Black Matrix and Ag Electrode Patterns by Photolithographic Process for High Resolution PDPJ. Y. So, H. Y. Kwon, S. K. Kim, and L. S. Park (Kyungpook Nat′l Univ., Korea)Black matrix and Ag electrode with uniform line pitches were successfully fabricated through the photolithographic process by using the photosensitive black pastes and Ag pastes with optimized photosensitive properties for black and Ag pastes in the photolithographic process was investigated with the variation of photosensitive BM and Ag pastes and the photolithography process conditions. The important components and formulation of the pholosensitive BM and Ag paste we discussed.

P-51

Lead Free, Low Temperature Sealing Materials for Soda Lime Glass Substrates in Plasma Display Panel (PDP)H. Lee, J. H. Hwang, T.-Y. Lim (KICET, Korea), Y.-H. Kim, S.-H. Lee, I.-W. Kim, and J.-K. Lee (CERA LTD, Korea)New glass compositions for lead free, low temperature sealing glass frit was examined in ZnO-V2O5-P2O5 glass system which can be used sealing material for PDP to be made of soda lime glass substrates. Among many glass compositions, KFS-C glass showed low glass transition point (Tg) and good fluidity and adhesion characteristics when it was tested by flow button method at low temperature of 420. …

P-52

Decay and Diffusion Characteristic of Electron and Ion Surface Charges on MgOH. J. Syn (Seoul Nat′l Univ., Korea), D. C. Jeong (Hoseo Univ., Korea), T. H. Lee, and K. W. Whang (Seoul Nat′l Univ., Korea)In this work, we measured the spatiotemporal surface charge distribution by the longitudinal electro-optic amplitude modulation method with BSO single crystal to investigate the decay and diffusion characteristics of surface charges in three types of MgO. The speed of decay and diffusion of two different kinds doped MgO is compared with those of pure MgO. The difference in the characteristics of the …

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P-53

Role of Redeposition of Sputtered Mg Particles in Image StickingN. Nikishin, A. Manakhov, Y.-K. Kim, M. Hur, and E.-G. Heo (Samsung SDI, Korea)One of important factors responsible for image sticking in AC PDP is a sputtering of MgO layer under ionic bombardment. Sputtered Mg particles can migrate to the neighbor cells, where the migration makes a change of discharge condition. It leads to the local non-uniformity of a luminescence in the panel, resulting in the image sticking.

P-54

Adsorption Properties of MgO Protective Layer in AC PDPA. Manakhov, N. Nikishin, M. Hur, and E. G. Heo (Samsung SDI, Korea)We have studied the adsorption of contaminations on the MgO protective layer by Thermal Desorption Spectrometry (TDS). The result shows that the increase in exposure time, MgO thickness and humidity multiply the quantity of adsorbed contaminations. It is also found that the desorption activation energy and contamination quantity is decreased by the additional firing process of MgO layer under oxygen environment.

P-55

Comparative Studies between the Negative Waveform and the Conventional Positive Waveform during Reset PeriodC. Eom, H. Lim, J. Lee (Dankook Univ., Korea), B. Kong, H. Park, S. Moon (LG Electronics Digital Display R&D Center, Korea), and J. Kang (Dankook Univ., Korea)A new reset waveform with negative ramp pulse was proposed. Comparative experiments between the negative and positive wave forms were performed. During reset period, IR distributions and luminance of black and white conditions were measured with the 42-inch XGA PDP module. The negative waveform improved contrast ratio about 15.4 ~ 22.5 % than the positive waveform by lowing the black luminance in reset period. Z bias (= Vbb) of the positive waveform was 27 V higher than the negative waveform.

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A New Single Sustain Waveform with Auxiliary Address Pulse in ac PDPW.-H. Park, H.-M. Lim, J.-Y. Lee, and J. W. Kang (Dankook Univ., Korea)To improve the luminance in ac PDP, a new single sustain waveform with auxiliary address pulse is proposed. The new single sustain waveform was examined with 2 dimensional fluid codes and related experiments were performed with 42-inch XGA PDP module. At the same sustain level (= 180 V), the new waveform showed 3.6 times higher IR emission than the general waveform without auxiliary address pulse.

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Electric Field Distribution and Discharge Characteristics in Accordance with ITO Electrode Structures in AC-PDPS. H. Cho, P. Y. Oh, J. H. Kim, Y. J. Hong, G. C. Kwon, G. S. Cho, and E. H. Choi (Kwangwoon Univ., Korea)In this study, the electric field distributions have been investigated by simulation in accordance with the various shapes of ITO-electrodes. Also we have measured the density of excited Xe atoms in the 1s5 state in discharge cell, where the gap distance of 60 um, gas pressure of 400 Torr, Xe contents of 7%, and sustaining voltage of 200 V are kept in this experiment. …

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Influence of Sintering Temperature of MgO Pellet on the Electro-optical Characteristics of Alternating Current Plasma Display Panel (AC-PDP)S. H. Hong, C. G. Son (Kwangwoon Univ., Korea), S. Jung, J. S. Kim (Ceramics & Chemicals Tech. Inc., Korea), J. H. Paik (Korea Inst. of Ceramic Eng. & Tech., Korea), and E. H. Choi (Kwangwoon Univ., Korea)We have investigated the electro-optical characteristics of AC-PDP with different MgO protective layers, which have been deposited by electron beam evaporation from various sintered pellets with different temperatures. We have measured the secondary electron emission coefficient (γ) by using the Gamma Focused Ion Beam (γ-FIB) system, the static margin, and the address delay time. …

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Three-dimensional Fluid Simulation for the Variation of Electrode Geometry in ITO-less PDP CellsI. C. Song, S. W. Hwang, S. Y. Cho (Pusan Nat′l Univ., Korea), D.-K. Lee (Dong-Eue Univ., Korea), H.-J. Lee, J.-H. Park, and H. J. Lee (Pusan Nat′l Univ., Korea)Several ITO-less PDP cell structures are presented to improve luminous efficacy. The ITOless PDP have been applied recently at actual panel manufacture. The influence of ITO-less PDP cell structure on the discharge characteristics has been investigated by using three-dimensional fluid simulation. …

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Effects of Aluminum Fence-type Electrode Design on Characteristics of AC-PDPS.-Y. Lee (HongIk Univ., Korea), D. H. Lee (IMI Inc., Korea), and Y.-S. Kim (Hongik Univ., Korea)In an attempt to enhance luminance efficiency and to reduce discharge delays of test panels with aluminum fence-electrodes, various designs of the electrodes were prepared by chemically etching the aluminum foils bonded to soda-lime glass substrate via anodic bonding process. …

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Effects of Address Electrode Width on Address Discharge Under Variable Ambient Temperature in AC PDPS.-K. Jang, H.-S. Tae (Kyungpook Nat′l Univ., Korea), E.-Y. Jung, J.-C. Ahn, and M. S. Yoo (Samsung SDI, Korea)It is known that the address discharge delay time during an address period strongly depends on the wall charge leakage. It was observed that the wall charge leakage during an address period is related to both the address width and the ambient temperature. Accordingly, the effects of address electrode width on the address discharge and wall voltage variation during an address period were examined under variable temperatures.

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Electrical, Optical, and Thermal Properties of AZO Co- sputterd ITO Electrode for Organic Light Emitting DiodesY.-S. Park and H.-K. Kim (Komoh Nat′l Inst. of Tech., Korea)In this study, we report on the characteristics of Al-doped ZnO (AZO) co-sputtered indium tin oxide (ITO) films prepared by dual target direct current (DC) magnetron sputtering at room temperature for organic light emitting diodes (OLEDs). The electrical and optical properties of co-sputtered IAZTO electrode were critically dependent on the DC power of AZO. Furthermore, the characteristics of co-sputtered IAZTO electrode were influenced by rapid thermal annealing temperature.

P-63

Passivation of Organic Light Emitting Diodes with Al2O3/ Ag/Al2O3 Multilayer Thin Films Grown by Twin Target Sputtering SystemJ.-A. Jeong and H.-K. Kim (Kumoh Nat′l Inst. of Tech., Korea)The characteristics of Al2O3/Ag/Al2O3 multilayer passivaton prepared by twin target sputtering (TTS) system for organic light emitting diodes. The Al2O3/Ag/Al2O3 multilayer thin film passivation on a PET substrate had a high transmittance of 86.44 % and low water vapor transmission rate (WVTR) of 0.011 g/m2-day due to the surface plasmon resonance (SPR) effect of Ag interlayer and effective multilayer structure for preventing the intrusion of water vapor. …

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Performance Analysis of Layered and Blended Organic Light-emitting DiodesJ. Park, Y. C. Yim, G. S. Heo, T. W. Kim, J. H. Lee (Korea Inst. of Industrial Tech., Korea), and S. H. Park (Catholic Univ. of Daegu, Korea)We make performance simulations of three different organic light-emitting diodes (OLEDs), one of which is based on a conventional layered structure and the others on a blended structure where an emitting layer (EML) is either uniformly or stepwise mixed with an electron transport layer (ETL), Tris-(8-hydroxyquinoline) aluminum (Alq3).

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High Efficiency and Long Lifetime for Organic Light-emitting Diode using a New Electron Transport MaterialY. Miyashita, O. Mochizuki, T. Tanaka (Tosoh Corporation, Japan), and H. Aihara (Sagami Chemical Research Center, Japan)We demonstrated high power efficiency and long lifetime for organic light-emitting diode (OLED) using a new electron transport material (ETM-1). A power efficiency of the device with ETM-1 was improved compared to a standard device using tris(8-hydroxy-quinolinate)aluminum (Alq3). Moreover, the lifetime was 4 times longer than the standard device.

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OLED Analog Behavioral Modeling Based on PhysicsS. G. Lee and R. Hattori (Kyushu Univ., Japan)The physical OLED analog behavioral model for SPICE simulation has been described using Verilog-A language. The model is based on the carrier-balance between the hole and electron injected through Schottky barrier at anode and cathode. The accuracy of this model was examined by comparing with the results from device simulation.

P-67

Molecular Engineering of Blue Organic Light Emitting Materials Based on Diarylamino-fluoreneK. H. Lee, Y. S. Kwon, L. K. Kang (Sungkyunkwan Univ., Korea), G. Y. Kim, J. H. Seo, Y. K. Kim (Hongik Univ., Korea), and S. S. Yoon (Sungkyunkwan Univ., Korea)We demonstrated the efficient blue organic light-emitting diodes (OLEDs) by employing diarylamino-fluorene derived blue fluorescent molecules as dopants. Among those, a device exhibited blue emission with the luminous efficiency of 11.2 cd/A at 20 mA/cm2, the external quantum efficiency of 9.7% at 20 mA/cm2, and the CIEx,y coordinates of (x=0.163, y=0.259) at 8V.

P-68

Correlation between Host Materials and Device Performances of Phosphorescent White Organic Light-emitting Diodes with Blue/Orange/Blue Stacked Emitting StructureC. W. Joo (Dankook Univ., Korea), S. H. Kim (Seoul Nat′l Univ., Korea), K. S. Yook, S. O. Jeon, and J. Y. Lee (Dankook Univ., Korea)A mixed host structure of TCTA and TPBI was used in orange emitting layer and host composition was critical to device performances of PHWOLEDs. PHWOLEDs with TPBI host in orange emitting layer showed high quantum efficiency of 10.3 % at 1000 cd/m2 with little change of CIE coordinates of (0.32, 0.34) from 100 cd/m2 to 10,000 cd/m2.

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Characteristics of Vertical Type Organic Light Emitting Transistor using C60 as a N-type Semiconductor Material and MEH-PPV as an Emitting PolymerJ. B. Lee, H. S. Jin, and S. Y. Oh (Sogang Univ., Korea)We have fabricated vertical type organic thin film transistor using C60 as a n-type active material to improve the problems of conventional OTFTs. In general, it can be argued that the characteristics of organic transistor were influenced by carrier mobility and density. We have used several kinds of metals as source and gate electrodes to optimize the device characteristics using C60. …

P-70

Dependence of Resistance and Capacitance of Organic Light Emitting Diode (OLED) on Applied VoltageS. Lee (Sunmoon Univ., Korea), W. Im (Neoview Kolon Co., Ltd., Korea), and S. Lim (Dankook Univ., Korea)Organic light emitting diodes (OLEDs) with multiple organic layers were fabricated to obtain and to evaluate an equivalent resistance and an equivalent capacitance of OLED device. The staircase voltage with an increasing period and a constant period was designed and applied to the OLED. The resistance of OLED was found to decrease from 270 k_ to 2 K_ as applied voltage increased after turn on. …

P-71

Phenyl-Naphthyl Amine Effect of New Phenothiazine Derivatives with High Tg for Hole Injection and Hole Transporting MaterialsS.-K. Kim (Catholic Univ. of Korea, Korea), J.-H. Lee (Chungju Nat′l Univ., Korea), and J.-W. Park (Catholic Univ. of Korea, Korea)We synthesized a new HIL and HTL materials by using phenothiazinly moiety, 1,4-diphenothiazyl-benzene [DPtzB], 3’,7’,3’’,7’’-tetrakis(N-phenyl-2- naphthylamine)-1,4-diphenothiazyl-benzene[PNA-DPtzB]. Synthesized materials exhibited high Tg in the range of 175 – 202. These values are much better than commonly used hole transporting materials (2-TNATA and NPB). The OLED device that used DPtzB as a HIL showed the highest efficiency of 4.31cd/A at 10mA/cm2.

P-72

The Study of New Host Materials for Solution-processed Green Organic ElectrophosphorescenceS.-H. Jung, H.-J. Lee, Y.-H. Kim, H.-S. Kim, E.-S. Yu, M.-Y. Chae, and T.-W. Chang (Cheil Industries Inc, Korea)We report the syntheses, photophysical properties and device performances of solution processible host material for green-phosphorescent OLEDs. The butterfly-shaped new host materials with nonconjugated linkage of carbazole and fluorene moieties have large triple energy band gap around 2.8 eV. …

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Synthesis of Conjugated Polymers with Fluorene and Biphenylamine and Application of PLED DevicesE. J. Park, H. Y. Kwon, and L. S. Park (Kyungpook Nat′l Univ., Korea)Four kinds of copolymers with fluorene and biphenylamine units were synthesized by palladium-catalyzed polycondensation reaction. These polymers were characterized in terms of their UV/Visible and photoluminescence (PL) properties in solution and film state. These polymers were also studied as a hole transporting material in the polymer light emitting diode (PLED) devices.

P-74

Low Voltage Driving Red Phosphorescent Organic Light- emitting DevicesT.-Y. Kim, W.-G. Suh, and D.-G. Moon (Soonchunhyang Univ., Korea)We have developed low voltage driving red phosphorescent organic light-emitting devices using a new electron transport layer. Ir(piq)3 and CBP were used as a phosphorescent dopant and an emission host, respectively. The device exhibits a luminance of 1000 cd/m2 at a voltage of 2.8 V. This high luminance at low voltage results from a high electron conduction behavior of the new electron transport layer.

P-75

New Green Phosphorescent Organic Light Emitting Device with the (TCTA/TCTA0.5TPBI0.5/TPBI):Ir(ppy)3 Emission LayerJ. G. Jang, S. B. Shin, H. K. Shin, and W. K. Kim (Dankook Univ., Korea)New green light emitting phosphorescent devices with host structure of TCTA[4,4′,4″-tris(N-carbazolyl)-triphe nylamine]/TCTA0.5TPBi0.5/TPBI[1,3,5- tris(N-phenylbenz imiazole-2-yl)benzene] were proposed and investigated according to the thickness combination of host layers and the doping level of Ir(ppy)3[tris(2-phenylpyridine) iridium(III)].

P-76

Blue-Emitting Heteroleptic Iridium(III) Complexes Based on Fluorinated 2-phenyl-4-methoxypyridineS. C. Lee and Y. S. Kim (Hongik Univ., Korea)New iridium complexes with 2-(3’,5’-bis-trifluoromethyl phenyl)-4-metoxypyridine [(CF3)2ppyOMe] were synthesized and characterized for blue phosphorescent materials. It was found that Ir[(CF3)2ppyOMe]2(acac) gives blue emission at 471 nm with strong luminescence efficiency. We discuss the role played by electron withdrawing substituents and also how the ancillary ligand influences the emission peak.

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Pixel Circuit with High Immunity to the Degradation of TFTs and OLED for AMOLED DisplaysC.-L. Lin and C.-D. Tu (Nat′l Cheng Kung Univ., Taiwan)A simple voltage compensation pixel circuit for AMOLED is produced using low temperature polycrystalline silicon (LTPS) technology. Its operation is verified by AIM-SPICE. Simulation results show that the pixel circuit has high immunity to variation of LTPS-TFT and reduces the drop in luminance due to the degradation of the OLED.

P-78

Tetra-chromatic White Phosphorescent Organic Light-emitting Diodes with an External Color Tuning LayerC.-S. Chang, P.-T. Liu, M.-H. Ho, and C. H. Chen (Nat′l Chiao Tung Univ., China)A highly efficient white phosphorescent OLED with a “tetra-chromatic” emission was fabricated by using an external color tuning layer (ECTL) which is composed of a layer of greenish yellow organic dye dispersed inPMMA on the outside of the glass. The ECTL combining with a lower red dopant concentration in the device has been found to improve the efficiency of a conventional WOLED by more than 27%.

P-79

A Study on Plasma-assisted Patterning and Doubly Deposited Cathode for Improvement of AMOLED Common Electrode IR DropJ. Yang, J. Kwak, C. Lee, and Y. Hong (Seoul Nat′l Univ., Korea)In order to reduce IR drop through common electrode in AMOLED, we propose a novel method to form electrical contact between highly-conductive bus lines and common electrode by using a plasma-assisted patterning of OLED layers and double deposition of the common electrode. Plasma- assisted patterning effects on OLED performance and degradation have been investigated. This patterning method caused turn-on voltage decrease, current flow increase at the same applied OLED voltages, quantum efficiency decrease, and rapid degradation at early stage during the lifetime test. However, comparable 70% luminance lifetime were obtained for both patterned and non-patterned OLEDs

P-80

The Effect of Oxygen Doping on Organic Light Emitting Diodes by Oxygen Plasma TreatmentK. Hong, K. Kim, S. J. Kim, J.-L. Lee (POSTECH, Korea), H. W. Choi, and Y.-H. Tak (LG Display Co., Ltd., Korea)By the oxygen plasma exposure to the organic light-emitting diodes, the turn-on voltage decreased from 10.5 to 7 V and luminance increased from 470 to 852 cd/m2. Synchrotron radiation photoelectron spectroscopy results showed that during oxygen plasma exposure, oxygen ions were diffused into organic layer and induced p-type doping effect.

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New Metric for Short-range Uniformity of AMOLEDsA. Arkhipov, B.-W. Lee, K. Park, C. Kim, and J. Lee (Samsung Electronics Co., Ltd., Korea)The variations of the TFT characteristics in AMOLEDs result in the decrease of the uniformity of the displays. Measurement of the long-range uniformity (LRU) is straightforward. However, there is no method for measuring the short-range uniformity (SRU) yet. Quantifying the SRU is important in evaluating various TFT backplanes and compensation circuits. We propose new methods for measuring SRU.

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High Performance Top-emitting OLEDs with Copper Iodide- doped Hole Injection LayerJ.-H. Lee, D.-S. Leem, and J.-J. Kim (Seoul Nat′l Univ., Korea)Efficient top-emitting organic light-emitting diodes were fabricated using copper iodide (CuI) doped NPB as a pdoped hole injection layer to improve hole injection from a silver bottom electrode. The enhanced hole injection is originated from the formation of the charge transfer complex between CuI and NPB. The devices result in high efficiency of 69 cd/A with almost Lambertian emission pattern.

P-83

Highly Efficient Green Phosphorescent Organic Light Emitting DiodesS.-H. Lee, H.-D. Park, J.-W. Kang, H.-J. Kim, and J.-J. Kim (Seoul Nat′l Univ., Korea)We have developed green phosphorescent organic light-emitting diodes (OLEDs) with high quantum efficiency. Wide-energy-gap material, 1,1-bis [(di-4-tolylamino) phenyl]cyclohexane (TAPC), with high triplet energy level was used as a hole transporting layer. Electrophosphorescent devices fabricated using TAPC as a hole-transporting layer and N,N’-dicarbazolyl- 4,4’-biphenyl (CBP) doped with fac-tris(2-phenylpyridine) iridium [Ir(ppy)3] as the emitting layer showed the maximum external quantum efficiency (ηext) of 19.8 %, which is …

P-84

Effects of Dielectric Capping Layer in the Phosphorescent Top Emitting Organic Light Emitting DiodesS.-Y. Kim, D.-S. Leem, J.-H. Lee, and J.-J. Kim (Seoul Nat′l Univ., Korea)Effects of a dielectric capping layer on the luminous characteristics of top emitting organic light emitting diodes (TOLEDs) have been analyzed using a classical electromagnetic theory. Special attention was given to the influence of the cavity length on the effectiveness of the capping layer. The luminance characteristics of the TOLEDs influenced by the combined effects of the cavity length and the capping layer thickness. Furthermore, these combined effects also modify the emission spectrum and pattern of the TOLEDs, which result in the improvement of …

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A Stable and Efficient Host Material Having Tetraphenylsilane for Phosphorescent Organic Light Emitting DiodesH.-D. Park, J.-W. Kang (Seoul Nat′l Univ., Korea), D.-S. Lee (Dongwoo Fine-Chem Co., Ltd., Korea), J. W. Kim, W.-I. Jeong, Y.-S. Park, S.-H. Lee (Seoul Nat′l Univ., Korea), K. Go, J.-S. Lee (Dongwoo Fine-Chem Co., Ltd., Korea), H.-J. Kim, and J.-J. Kim (Seoul Nat′l Univ., Korea)A host material containing tetraphenylsilane, 9-(4-triphenylsilanyl- (1,1’4,1’’)-terphenyl-4”-yl)-9H-cabazole (TSTC), was synthesized for green phosphorescent organic emitting diodes. Ir(ppy)3 based OLEDs using TSTC host and DTBT (2,4-diphenyl-6-(4’yl)-1,3,5-triazine) hole blocking layer (HBL) showed the maximum external quantum efficiency of …

P-86

Effect of HfOX Treatment on ITO Surface of Organic Light Emitting Diodes using Impedance Spectroscopy AnalysisJ. Cho, H. Park, K. Han , S. Y. Sohn, D. G. Jung, and J. Yi (Sungkyunkwan Univ., Korea)In this work, we used impedance spectroscopy analysis to determine the effect of the HfOX treatment on the surface of ITO and to model the equivalent circuit for OLEDs. Devices with an ITO/Organic material/Al structure can be modeled as resistances and capacitances arranged in parallel or in series. …

P-87

Colorimetric Characteristics Evaluation of OLED and LCDY. S. Baek, H. S. Kim, S. O. Park (Daejin Univ., Korea), and Y. J. Kim (Univ. of Leeds, Korea)In this study, colorimetric characteristics of a 2.2-inch iriver MP4 based upon OLED was evaluated and compared with another MP4 based upon Liquid Crystal Display (LCD). According to IEC61966-4, the two displays were tested in terms of spectral power distribution, tone reproduction curve (TRC), luminance, contrast, correlated color temperature, 2D color gamut and spatial uniformity. …

P-88

Enhancement Mechanisms of Luminance Efficiency in Red Organic Light-emitting Devices Utilizing a Double Electron Transport Layer Consisting of an Al-doped Layer and an Undoped LayerD. C. Choo, H. S. Bang, S. D. Ahn, K. S. Lee, S. Y. Seo, J. S. Yang, T. W. Kim (Hanyang Univ., Korea), J. H. Seo, and Y. K. Kim (Hong-ik Univ., Korea)The luminance efficiency of the red organic lightemitting devices fabricated utilizing a double electron transport layer (ETL) consisting of an Al-doped and an undoped layer was investigated. The Al atoms existing in the ETL acted as hole blocking sites, resulting in an increase in the …

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A Driving Method for Large-size AMOLED Displays using a-Si:H TFTsU.-G. Min, H.-J. In, and O.-K. Kwon (Hanyang Univ., Korea)A voltage-programming pixel circuit, which compensates the threshold voltage shift of TFTs and the degradation of OLED, is proposed for large sized a-Si:H active matrix organic light emitting diode (AMOLED) applications. Considering threshold voltage variation (or shift), OLED degradation and reverse bias annealing, HSPICE simulation results indicate that luminance error of every gray level is less than 0.4 LSB under the condition of +1V threshold voltage shift and from -0.2 LSB to 2.6 LSB within 30% degradation of OLED in the case of 40-inch full HDTV condition.

P-90

Enhancement of Outcoupling Efficiency of OLEDs by using Nanoimprinted Polymer NanostructuresS. Jeon, J.-W. Kang, H.-D. Park (Seoul Nat′l Univ., Korea), J. Shim, J.-H. Jeong (KIMM, Korea), S.-H. Kim (KAIST, Korea), J. R. Youn, and J.-J. Kim (Seoul Nat′l Univ., Korea)An etch-less simple method was developed to fabricate two-dimensional nanostructures on glass substrate directly by using UV curable polymer resin and UV nanoimprint lithography in order to improve output coupling efficiency of OLEDs. OLEDs integrated on nanoimprinted substrates enhanced electro-luminance intensity by up to 50% compared with the conventional device.

P-91

Surface Energy Control of ITO Substrate for Inkjet Printing of PEDOT/PSSM. K. Kim, S. H. Lee, J. Y. Hwang, K. T. Kang, and H. S. Kang (KITECH, Korea)Inkjet printing is being considered as an alternative to the conventional lithography in the electronic industry. Surface energy control of substrate is a critical issue in controlling the dimension of microsrtuctures by the inkjet printing. This study introduces the surface energy control of ITO substrate for inkjet printing of PEDOT/PSS

P-92

Co-deposition and Tuned Blue Emission Color from New Tetraphenylethylene DerivativesS.-K. Kim and J.-W. Park (Catholic Univ. of Korea, Korea)By combining tetraphenylethylene and anthracene, we synthesized 9,10-bis(4-(1,2,2-triphenylvinyl)phenyl) anthracene [BTPPA] and 1,2-di (4’-tert-butylphenyl)-1,2-bis(4’-(anthracene-9-yl)phenyl)ethene [BPBAPE]; both BTPPA and BPBAPE have similar band-gaps, however their PL spectra were shifted by about 30 nm with respect to each other. …

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Contrast Improvement of OLED using Multi-layer of Metal and Metal OxideS. W. Hwang, S. H. Lee, J. Y. Choi, H. S. Yoon, Y. H. Kim, S. J. Chae, and W. Y. Kim (Hoseo Univ., Korea)Inorganic metal multi-layer(IMML) consisting of Al/Al:SiO/Al was developed as a cathode for OLED to reduce the reflectance generated from ambient light. Device structure of green OLED was ITO/2-TNATA/α-NPD/Alq3: C545T/Balq/Alq3/LiF/IMML and IMML was composed of three different layers: thin aluminum layer, aluminum layer doped with silicon monoxide and thick aluminum layer. Average reflectance of green OLED was 9.63% while that of conventional OLED with or without polarizer showed the average reflectance of 8.54% and 66% respectively at …

P-94

Synthesis and Electroluminescent Properties of Highly Twisted Anthracene DerivativesS. J. Park, J. W. Park, S. O. Jung, Y.-H. Kim, and S.-K. Kwon (Gyeongsang Nat′l Univ., Korea)The anthracene derivatives were synthesized by Suzuki coupling reaction. The thermal, optical and electronic properties of MNAn and BIPAn were investigated by thermogravimetric analysis (TGA), differential scanning calorimetry(DSC), UV-vis absorption, photoluminescen ce spectroscopies, and cyclic voltammetry. The materials exhibit high thermal stability and high per formance in EL devices.

P-95

Fabrication of WOLED with Orange and Blue Emissive Layers using Two Complementary Color MethodJ. Y. Choi, H. S. Yoon, S. H. Lee, Y. H. Kim, S. J. Chae, and W. Y. Kim (Hoseo Univ., Korea)WOLED devices were fabricated using two complementary color method with two emissive layers of blue and orange color respectively. WOLED’s color purity was optimized as changing thickness of blue emissive DPVBi layer with most efficient red emissive layer doped with 0.2% DCJTB in Alq3 and obtained better white color coordinates of (0.36, 0.33) at 9V.

P-96

Rapid Calibration of Organic Layer Thickness by ETFOS SoftwareF.-S. Juang (Nat′l Formosa Univ., Taiwan), J.-J. Huang (Nat′l Cheng Kung Univ., Taiwan), S.-H. Wang, Y.-H. Liu (Nat′l Formosa Univ., Taiwan), and Y.-K. Su (Nat′l Cheng Kung Univ., Taiwan)By ETFOS software simulation to swiftly find out the shortcomings of the device structure and conserve the wastage of time cost in experiments, including the instruments deviations or human errors. Thereby we can calibrate the correct organic layer thickness by comparing the EL spectra with different NPB thicknesses.

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P-97

Study of Plasma Process Induced Damages in Metal Oxides as Buffer Layer for Inverted Top Emission Organic Light Emitting DiodesJ.-H. Kim, Y.-J. Lee, J.-N. Jang, B.-C. Song, and M. Hong (Korea Univ., Korea)In the fabrication of inverted top emission organic light emitting diodes (ITOLEDs), the organic layers are damaged by high-energy plasma sputtering process for transparent top anode. In this study, the plasma process induced damages on metal oxide hole injection layers (HILs) including WO3, MoO3, and V2O5 as buffer layer are examined. …

P-98

Synthesis and Electroluminescence Properties of Novel Deep Blue Emitting 6,12-dihydro-diindeno[1,2-b;1′,2′-e] pyrazine DerivativesY.-I. Park, J.-H. Son, J.-S. Kang, S.-K. Kim (Catholic Univ., Korea), J.-H. Lee (Chungju Nat′l Univ., Korea), and J.-W. Park (Catholic Univ., Korea)We report the synthesis of blue emitting materials with a new core structure containing indenopyrazine. Non-doped device using one of these materials as a blue emitter was found to exhibit high external quantumn efficiency of 4.6% and excellent color purity of (0.154, 0.078) as well as narrow emission band of 47nm FWHM.

P-99

Novel Host Materials for Phosphorescent OLEDs with Long LifetimeY. Kim, E. Yu, N. Kim, S. Jung, H. Kim, H. Lee, E. Kang, M. Chae, and T. Chang (Cheil Industries Inc., Korea)We have developed a novel bipolar host material with both electron and hole transporting characteristics. Since CGH(Cheil Green Host) has some electron transporting characteristics, it shows increased luminance efficiency in device including TCTA and without HBL(hole blocking layer:BAlq). Maximum power efficency of CGH was 27.4lm/W at the device structure ITO/DNTPD(60)/NPB(20)/TCTA(10)/EML(30)/Alq3(20)/LIF(1)/Al. …

P-100

Novel Driving Scheme to Remove Residual Image Sticking in AMOLEDK Parikh, J. Choi, K. Cho, J. Huh, K. Park, B. Jeong, Y.-H. Park, T.-Y. Kim, B. Lee, and C. Kim (Samsung Electronics Co., Ltd., Korea)We hereby report novel driving scheme to eliminate effect of “residual” image sticking (RRI) problem which arises due to hysteresis problem in Thin Film Transistor (TFT) in AMOLED Displays. The driving scheme applies “black” voltage after every data voltage period in order to drive AMOLED in uni-direction. …

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A New Type 1.0mm × 0.5mm Light Emitting Diode using AlInGaN Cell Structure and Its Display ModuleB.-S. Park, S.-W. Kim (Univ. of Seoul, Korea), S.-G. Lee, S.-I. Son (HSDPA Group, Korea), E.-T. Kim (ETRI, Korea), and C.-J. Kim (Univ. of Seoul, Korea)The main goal of this work is to fabricate light emitting diode (LED) module and apply it to mobile handset. We first fabricated the blue-color LED based on the AlInGaN cell structure with size of 200 µm × 200 µm. Also we proposed a new 1.0 mm × 0.5 mm (1005size) packaging procedure for the LED cell. Thus the overall dimension of our LED cell was as small as 1.0 mm × 0.5 mm × 0.4 mm (W × L × T). As far as we knew it was the first time that this small LED cell dimension had been fabricated and operated.

P-102

Preparation and Photoluminescence Properties of Ba1-xMxGa2S4:Eu2+ (M = Ca, Sr) PhosphorH. S. Yoo, S. W. Kim, J. Y. Han, B. J. Park, and D. Y. Jeon (KAIST, Korea)Ba1-xMxGa2S4:Eu2+ (M = Ca, Sr) phosphor was prepared for white light emitting diodes application. Photoluminescence (PL) emission and excitation bands were red-shifted with increase of Ca and Sr content due to the crystal field effect. Moreover, the PL intensity under 450 nm was increased by substitution of Ca and Sr.

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Rietveld Refinement Study on Variation of Emission Wavelength of (Sr1-x,Cax)2MgSi2O7:Eu2+ Phosphor for White LED ApplicationsK. H. Kwon, W. B. Im, H. S. Jang, H. S. Yoo, and D. Y. Jeon (KAIST, Korea)In this study, a blue-emitting Sr2MgSi2O7:Eu2+ (SMS) phosphor for white light-emitting diodes is reported. Through transition of 4f → 5d in Eu2+, SMS showed a strong blue emission under UV excitation. Additionally, the variation of emission wavelength of SMS is explained by crystal field effect and is supported by rietveld refinement.

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Effect of Bi3+ Addition on Photoluminescence of (Y,Gd) (V,P)O4:Eu PhosphorH.-A. Kyung, S. Choi (KRICT, Korea), T.-Y. Seong (Korea Univ., Korea), and H.-K. Jung (KRICT, Korea)The structural and optical properties on Bi3+ addition in (Y,Gd)(V,P) O4:Eu3+ red phosphor were investigated. With the addition of Bi3+, the band edge in excitation spectrum shifts toward longer wavelength region, resulting in remarkable enhancement of the red emission intensity at 619 nm.

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Photoelectric Characteristics of a-Si:H Thin Film Transistor by Spectral Properties of Various Backlight SourcesK. M. Choi, S. J. Kwon, and E. S. Cho (Kyungwon Univ., Korea)Photo leakage characteristics of a-Si:H TFT were obtained for the illuminations from various backlight sources and the results were compared and analyzed in terms of the photoelectric properties of light. The analysis shows that the photocurrents are related to the wavelengths of the peak intensities of the spectrums of light sources.

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Cu2+-addition Effect on Luminescence of ZnS:Cu,Cl Blue- green PhosphorsT.-Y. Cho, J.-I. Park, S.-D. Han, J. Gwak (Korea Inst. of Energy Research, Korea), D.-H. Shin (EL Korea Corp., Korea), I.-S. Chun, and C.-H. Han (Korea Inst. of Energy Research, Korea)ZnS:Cu,Cl blue-green phosphors were prepared by conventional solid state reaction. Copper activator of different concentrations was doped into ZnS structure at two firing steps. The luminescence characteristics dependent on Cu2+ doping concentration of the phosphors has been investigated for inorganic electroluminescent device.

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Luminescent Characteristics of a Blue-emitting CaAl2Si2O8: Eu2+ Phosphor and the Effect of Boron Ion SubstitutionB.-H. Kwon, S. Vaidyanathan, H. Li, H. S. Jang, H. S. Yoo, and D. Y. Jeon (KAIST, Korea)Blue-emitting CaAl2Si2O8:Eu2+(CAS:Eu2+) phosphor, prepared by solid-state reaction, is described in this paper. We researched the effect of boron ion substitution in the host materials. The phase and luminescent properties were investigated using the powder X-ray diffraction(XRD) and photoluminescence(PL) spectra.

P-108

Luminescence Properties of Eu- and Mn- activated BaMgP2O7 as a Potential Red Phosphor for White EmissionY.-K. Kim, S. Choi, and H.-K. Jung (KRICT, Korea)BaMgP2O7:Eu,Mn phosphors for white emission were synthesized and their luminescent properties were investigated under UV excitation. The phosphor emits two colors: a blue band by Eu2+ and a red band by Mn2+. Due to the efficient energy transfer from Eu2+ to Mn2+, the red emission positioned at 615 nm is greatly enhanced with increasing Mn2+ content up to 17.5 mol%.

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Spectral Variations of Eu2+ Emission in Sr- or Ba-Silicate, Borate and Borosilicate HostsW.-S. Song, J.-S. Lee, and H. Yang (Hongik Univ., Korea)Depending on host environments, Eu2+ emission can be spectrally tuned by manipulating the energy levels between allowed 4f↔5d transition. Spectral variations of Eu2+ emission from narrow green emission to broad yellow emission band were achieved by varying the host lattices such as Sr- or Ba-silicate, borate, and borosilicate.

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Nanocrystalline Y3Al5O12:Ce Phosphor-based White Light- emitting Diodes Embedded with CdS:Mn/ZnS Core/Shell Quantum DotsJ.-U. Kim, D.-K. Lee, J.-J. Lee, and H. Yang (Hongik Univ., Korea)Yellow-emitting Y3Al5O12:Ce nanocrystalline phosphor and orange-emitting CdS:Mn/ZnS core/shell quantum dots were prepared by a modified polyol and a reverse micelle chemistry, respectively. To compensate a poor color rendering index of YAG:Ce nanocrystalline phosphor due to the lack of red spectral component, CdS:Mn/ZnS quantum dots were blended into YAG:Ce. Based on spectral evolutions in the blended systems, hybrid white light emitting diodes are fabricated and characterized.

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Synthesis and Luminescent Property Investigation of the Lu3Al5O12:Ce for the White LEDsS. J. Lee, J. K. Park, P. K. Bae, C. H. Kim, H. J. Chang (KRICT, Korea), and Y.-R. Kim (Yonsei Univ., Korea)In this report, cerium doped lutetium aluminate (Lu3Al5O12:Ce) phosphor has been synthesized by the solid state method under reduction atmosphere with mixture gas. The prepared phosphor shows a main luminescent peak at 555nm. Consequently, this phosphor is possible to be applicable to white LED lamp by InGaN chips.

P-112

Fabrication and Optical Properties of 2D Photonic Crystal Assisted Thin Film PhosphorsJ. R. Oh, K.-Y. Ko, and Y. R. Do (Kookmin Univ., Korea)This presentation introduces a simple strategy for producing 2D photonic crystal layers (PCL) with different structures. In an attempt to improve extraction efficiency from the thin film phosphors (TFPs), this study have examined the effects of the structural variables of the 2D PCLs on the light extraction efficiency of TFPs.

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Improvement in the Contrast Ratio of PDPs in the Bright Room using Pigmented Phosphors with Effective ReflectanceE. A. Moon, T. H. Moon, H. C. Lee, G. Y. Hong, J. S. Kim, and B. G. Ryu (LG Electronics Co., Ltd., Korea)In order to improve the contrast ratio of PDPs in the bright room, we decreased the panel reflection by coating phosphors with pigments. In this work, we investigated the panel reflectance with various sizes of the blue pigments and obtained good results by reducing the size of the …

P-114

Surface Plasmon Resonance Effect of Ag Layer Inserted in a Highly Flexible Transparent IZTO/Ag/IZTO Multilayer Electrode for Flexible Organic Light Emitting DiodesH.-K. Park, N.-H. Jun, K.-H. Choi, and H.-K. Kim (Kumoh Nat′l Inst. of Tech., Korea)We report on the Ag thickness effect on the electrical and optical properties of indium zinc tin oxide (IZTO)-Ag-IZTO multilayer electrode grown on a PET substrate and the surface plasmon effect of Ag layer on the optical properties of IZTO-Ag-IZTO electrode. Using an IZTO-Ag- IZTO multilayer with a total thickness below ~80 nm, we can obtain high-quality flexible electrode with very low sheet resistance, …

P-115

Characteristics of Flexible Indium Tin Oxide Electrode Grown by Continuous Roll-to-Roll Sputtering Process for Flexible DisplaysK.-H. Choi, S.-W. Cho, J.-A. Jeong, and H.-K. Kim (Kumoh Nat′l Inst. of Tech., Korea)The preparation and characteristics of flexible indium tin oxide electrodes grown on polyethylene terephthalate (PET) substrates using a specially designed roll-to-roll sputtering system for use in flexible optoelectronics In spite of low a PET substrate temperature, we can obtain the flexible electrode with a sheet resistance of 47.4 ohm/square and an average optical transmittance of 83.46 % in the green region of 500~550 nm wavelength. …

P-116

Highly Flexible, Transparent and Low Resistance IZO- Ag-IZO Multilayer Electrode for Flexible OLEDsS.-W. Cho, K.-H. Choi, J.-A. Jeong (Kumoh Nat′l Inst. of Tech., Korea), S. H. Lee, J.-J. Kim (Seoul Nat′l Univ., Korea), and H.-K. Kim (Kumoh Nat′l Inst. of Tech., Korea)Characteristics of indium-zinc-oxide (IZO)-Ag-IZO multilayer grown on a PET substrate were investigated for flexible organic emitting diodes. By inserting very thin Ag layer between amorphous IZO, IZO-Ag-IZO (IAI) multilayer anode exhibited remarkably reduced sheet resistance and high transmittance due to the surface plasmon resonance effect and Ag layer.

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Characteristics of ITO Electrode Films Grown on PET Substrate by Roll-to-Roll Facing Target Sputtering System for Flexible OLEDsS.-W. Cho, K.-H. Choi, J.-A. Jeong, B.-S. Kim, D.-J. Jeong, and H.-K. Kim (Kumoh Nat′l Inst. of Tech., Korea)We report on electrical and optical properties of flexible ITO electrode grown on PET substrate using a specially designed roll-to-roll facing target sputtering (R2R FTS) system at room temperature without conventional cooling drum. Due to effective confinement of high density plasma between ITO targets, we can grow a flexible ITO electrode without cooling drum at room temperature.

P-118

Barrier Property Enhancement of Plastic Substrates for Flexible Display by Inorganic-Organic Hybrid MultilayerH. G. Kim, H. Ryu, and S. S. Kim (Kyung Hee Univ., Korea)Inorganic-organic hybrid multilayers were formed on the plastic substrate to enhance the barrier properties of substrate to water vapor and oxygen transport. Plasma pretreatment of substrate with Ar/O2 lead to adhesion improvement and the densification of inorganic layer on the substrates. Combination of SiOxNy layer and silanenanoclay composite layer offered quite good barrier properties (WVTR and OTR) to PES substrate.

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Electrically Sstable Transparent Complementary Inverter with Organic-Inorganic Nano-Hybrid DielectricsM. S. Oh, K. Lee, K. H. Lee, S. H. Cha (Yonsei Univ., Korea), B. H. Lee, M. M. Sung (Hanyang Univ., Korea), and S. Im (Yonsei Univ., Korea)

P-120

Ink-jet Printability for FluidsD. Jang, D. Kim, and J. Moon (Yonsei Univ., Korea)We have investigated the inter-relationship between the ink-jet printability and the physical fluid properties by monitoring the droplet formation dynamics. Printability of the fluids was judged based on the inverse of Ohnesorge number (Z-1) that relates to the viscosity, surface tension, and density of the fluid.

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Optical Performance of Bent Polymer Network Liquid Crystal Films using Plastic SubstratesC.-W. Kuo, Y.-R. Lin, H.-L. Wang, C.-C. Liao (ITRI, Taiwan), P.-Y. Huang, J.-T. Shy (Nat′l Tsing Hua Univ., Taiwan), K. Lu, A. Tsai, R. Chang, and J. Chen (Innovision FlexTech Corp., Taiwan)We have studied the optical performance of flexible polymer network liquid crystal (PNLC) films at various bending states. Different measurement setups, wide and narrow opening angles of detector, were used to collect scatting light of PNLC films. The optical and dynamic properties of bent PNLC implied the change of LC domains.

P-122

Fabrication of Screen Printed Organic Thin-Film TransistorsJ.-S. Yu, J. Jo (KIMM, Korea), and D.-J. Kim (Chungnam Nat′l Univ., Korea)Printed organic thin-film transistors (OTFTs) were used in the fabrication of a screen- printed gate, source and drain electrodes on flexible plastic substrates using silver pastes, a coated polyvinylphenol dielectrics, and jetted bis(triisopropyl-silylethynyl) pentacene (TIPS-pentacene)organic semiconductor. The OTFTs printed using screen printing and soluble processes made it was possible to fabricate a printed OTFT with a channel length as small as 13 µm on plastic substrates; this was not possible using previous traditional printing techniques.

P-123

Synthesis and Characterization of Polyimide Films for Flexible Display SubstratesQ. H. Vu, J. W. Kim, and L.-S. Park (Kyungpook Nat′l Univ., Korea)A series novel films of polyimide (PI) and co-polyimide (Co-PI) containing fluorine with colorless, flexible properties was prepared by a two-step process from various commercial aromatic monomers such as 4,4′-(Hexafluoro iso propylidene) diphthalic anhydride(6FDA), 2,2′–Bis(Trifluoromethyl) benzidine (TFDB), 2,2-bis(3-amino-4-hydroxyphenyl) hexafluoropropane(AH6FP) and Bis(4-(3-aminophenoxy)phenyl)sulfone(BAS). Furthermore, these obtained transparent and flexible Co-PI films exhibited excellent thermal stability with the decomposition temperature (at 5% weight loss) around of …

P-124

Polymeric Flexible Field Effect Transistors using Oriented Poly(3-hexylthiophene-2,5-diyl)Y. B. Lee (Samsung Electronics Co., Ltd., Korea) and H.-K. Shim (KAIST, Korea)The properties of oriented poly(3-hexylthiophene-2,5-diyl) in field effect transistors (FETs) have been investigated through mechanical stretching process as the original. Silicon-based FETs shown high mobility of 0.02 cm2/V s after thermal treatment and 0.0092 cm2/V s at r.t. PET-based FETs were expected to show a similar performance in mobility to that of silicon-based FETs.

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The Simplified LDD Process of LTPS TFT on PI SubstrateG.-R. Hu, B.-C. Kung, K.-Y. He, C.-H. Cheng, Y.-S. Huang, C.-J. Liu, C.-J. Tsai, and J.-J. Huang (ITRI, Taiwan)Traditional LTPS TFT needs additional LDD process to decrease leakage current. However the fabrication process is no suitable for PI substrate. Additional laser multi-irradiation will damage the poly-Si to cause the TFT electrical degrade. Therefore we propose the simplified process to activate the N+ and N- at the same time.

P-126

Analysis of Interface Trap Density between Semiconductor- Gate Insulator with C-V CharacteristicsS.-H. Jeong, S.-M. Kim, and C.-K. Song (Dong-A Univ., Korea)In this paper, we analyzed interface trap density between pentacene and PVP and SiO2 gate dielectric by using high-low C-V characteristics. The interface trap density was 1013cm-2eV-1.

P-127

Fabrication of Ag-Paste Source/Drain Electrodes in OTFTs using Micro-Contact PrintingH. Kim, Y. Kim, and C. Song (Dong-A Univ., Korea)We used micro-contact printing for source and drain electrodes of OTFTs. The proper solvent of Ag paste and baking temperature were extracted for PVP gate dielectric and pentacene semiconductor. The mobility was 0.025 cm2/V.sec and on/off ratio was 2×105.

P-128

Electrical Properties of OTFTs and Inverters by using Ink-Jet Printing with Polyvinylphenol Insulator and TIPS- Pentacene SemiconductorR. Kang (Dong-A Univ., Korea), Y.-X. Xu (Kyungnam College of Information and Tech., Korea), and C. Song (Dong-A Univ., Korea)In this paper, we report electrical properties of OTFTs by using ink-jet printing with polyvinylphenol (PVP) for gate insulator and bis (triisopropylsilylenthynyl) pentacene (TIPS pentacene) for semiconductor. OTFTs produced the excellent performance with the mobility of 1.27 cm2/V.s for top contact structure(TCS) and inverter consisting of two OTFTs exhibited the gain of 6.75.

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Contact Resistance Extraction between Ink-Jet Printed PEDOT-PSS and Pentacene in OTFTsM.-K. Kim, R.-W. Kang, and C.-K. Song (Dong-A Univ., Korea)We enhanced the conductivity of PEDOT-PSS by mixing with glycerol and fabricated the low contact resistance of source and drain[S/D] electrodes of OTFT with PEDOTPSS by ink-jetting printing. The contact resistance was much smaller by seven times than Au with 200kΩ at VG=-5V. …

P-130

A Study on Properties of PVA/SiO2 Organic-Inorganic Hybrid Materials Barrier Layer Coated on Flexible Substrate (PEN)T. Koo, U. Farva (Yeungnam Univ., Korea), E. S. H. Yu, Y. Kim (Woongjin Chemical Ltd., Korea), and C. Park (Yeungnam Univ., Korea)Barrier coating properties of PVA/SiO2 on the flexible substrates (PEN) have been investigated. Thin layer of PVA/SiO2 organic-inorganic hybrid materials were deposited on PEN substrate by the spin-coating. The optical properties and surface roughness of barrier layer on flexible substrate were characterized by AFM, UV-Vis and WVTR/ OTR.

P-131

The Investigation of Flexible Flat Display in Improving FlexibilityC.-Y. Huang, K.-Y. Tsao, R.-S. Chou, W.-Y. Chiang (Tatung Univ., Taiwan), C.-N. Mo, and R. Lyu (Chunghwa Picture Tubes, Ltd., Taiwan)In this study, it was mainly focused on the mechanism and reliability performances of PI/PET composites after many times of curving. We developed a new process of spacer for flexible display to improve the maintenance of cell gap. This new process used the laser carving technology, which is widely applied on printing press, to produce the pattern of spacers and shaped both of the alignment film and spacers simultaneously by press of pattern. …

P-132

Low Temperature Curable Organic Gate Insulator for Organic Field-effect TransistorsJ.-Y. Kim (Seoul Nat′l Univ., Korea), M.-S. Jung, S.-Y. Lee, J.-M. Kim, and J.-J. Kim (Samsung Electronics Co., Ltd., Korea)Low-temperature curable organic insulator was prepared through blending of polyimide type base resin and cross-linking agent. The newly developed resin can be formed into films using a wet process and cured at 130°C. Using the low temperature cured film as the gate dielectric layer, the field effect mobility of 0.15 cm2/V⋅s was obtained from a pentacene field effect transistor in the saturation regime and …

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DPR System for Projection Displays - Today and TomorrowK. Li (Wavien, Inc., USA)With the advancements or LEDs and lasers in projection display applications, arc lamps still provide the most cost effective solution to high brightness display systems. When will arc lamps become obsolete, will be of great importance today and tomorrow? Given the fact that traditional elliptical and parabolic reflectors had been around for decades; Wavien’s new dual paraboloid reflector (DPR) technology with its unique imaging property enhances various aspects of the arc lamp performance will shed some light to this question. …

P-134

Electro-mechanical Analyses of Thin Film Transistors for Flexible DisplaysN. Saran, N. Roh, S. Kim, W. Lee, J. S. Kim, T. Hwang, S. Hong, M. Kim, S. Lim, and J. Souk (Samsung Electronics Co., Ltd., Korea)Good mechanical properties of thinfilm transistors on plastic substrates are an essential parameter in the development of robust flexible displays. In this paper, a careful investigation is carried out on TFT backplane on plastic substrates under cyclic bending conditions. Bending modes of tensile and compressive as well as parallel and perpendicular orientation- dependent bending of channel have been analyzed carefully. …

P-135

An Operating Circuits Design for Preventing Electrostatic Discharge in Liquid Crystal DisplaysJ.-Y. Jo (Samsung Electronics Co., Ltd., Korea) and J.-S. Yi (Sungkyunkwan Univ., Korea)An electrostatic discharge (ESD) or a noise supplied from the outside has an effect on communication between the timing controller (TCON) and the memory element (EEPROM) through the interface between the timing controller and the memory element in liquid crystal displays (LCD). Therefore, we must apply ESD protection methods to LCD operating circuits for a normal operation. …

P-136

Cost Effective 60Hz FHD LCD with 800Mbps AiPi TechnologyH. Nam, K. Y. Oh, S. K. Kim, N. D. Kim, B. H. Berkeley, S. S. Kim (Samsung Electronics Co., Ltd., Korea), Y. Lee (AnaPass Inc., Korea), and K. Nakajima (NEC Electronics Corp., Japan)AiPi technology incorporates an embedded clock and control scheme with a point-to-point bus topology, achieving the smallest possible number of interface lines between a timing controller and source drivers. A 46” AiPi-based 10-bit FHD prototype requires only 20 interface lines, compared to 38 lines for mini-LVDS. The measured maximum data rate per one data pair is more than 800Mbps.

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Characterization of Motion Interpolation in 120Hz SystemsB. H. Shin, K. Kim, M. Park, and B. H. Berkeley (Samsung Electronics Co., Ltd., Korea)Motion interpolation is adopted and has been spread widely into market since it is effective in reducing motion blur, which is considered as weak characteristic due to slow response time of liquid crystal and hold-type display. 120Hz driving using interpolated frames achieves better moving picture quality with less motion blur and less motion judder. However, errors in the interpolated frames can cause visual artifacts such as static text breakup, halos, and occlusions. This paper focuses on categorizing characteristics of visual artifacts and on reducing side-effects by using information from original frames in special cases.

P-138

Design of Mini-LVDS Output Buffer using Low-Temperature Poly-Silicon (LTPS) Thin-Film Transistor (TFT)Y.-J. Nam, K.-Y. Min, and C. Yoo (Hanyang Univ., Korea)Mini-LVDS has been widely used for high speed data transmission because it provides low EMI and high bandwidth for display driver. In this paper, a Mini-LVDS output buffer with LTPS TFT process is presented which provides sufficient performance in the presence of large variation in the threshold voltage and mobility and kink effects.

P-139

Table Lookup-Based Power Estimation for LCD PanelsJ.-B. Lee, S.-Y. Bang (Yonsei Univ., Korea), N.-D. Kim, S.-H. Moon, Y.-S. Lee (Samsung Electronics Co., Ltd., Korea), and E.-Y. Chung (Yonsei Univ., Korea)We present a novel power estimation technique for LCD panels. Our method considers the power consumed by each pixel as well as the inter-pixel power effect of the neighboring pixels. We implemented our method based on the table lookup model and its accuracy is about 98% compared to the actual measurement

P-140

Integrated Driver with Optical Compensation for Improved Uniformity of Emissive DisplaysS. Maeyaert, B. Bakeroot, J. Doutreloigne, A. Monté, P. Bauwens, and A. V. Calster (Ghent Univ., Belgium)Large area emissive displays have problems with non-uniform pixel characteristics and their individual ageing. A pixel integrated driver with pixel based optical feedback is presented to solve these problems. Photodetectors, optical feedback circuit and data handling capabilities are integrated in a high voltage CMOS technology.

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10-Bit Source Driver with Resistor-Resistor-String Digital to Analog Converter using Low Temperature Poly-Si TFTsJ.-S. Kang, H.-W. Kim, Y.-C. Sung, and O.-K. Kwon (Hanyang Univ., Korea)A 10-bit source driver using low temperature polysilicon(LTPS) TFTs is developed. To reduce the DAC area, the DAC structure including two 5-bit resistorstring DACs and analog buffer, which has analog adder is proposed. The source driver is fabricated using LTPS process and its one channel area is 3,200µm × 260µm. The simulated INL and DNL of output voltages are less than 3 LSB and 1 LSB, respectively.

P-142

The Evaluation Method for Viewing Angle Image Control (VIC) TechnologyJ.-B. Kwon, S.-C. Park, D.-G. Lee, L.-S. Lee, and B.-C. Ahn (LG Display Co., Ltd., Korea)A new evaluation method which named ‘Security Viewing Angle Factor (SVAF)’ was suggested for VIC (Viewing-angle Image Control) technology to quantify a visual hiding performance of LCD. Currently, Contrast Ration (CR) is the general method to evaluate VIC technology. However, CR shows a significant difference when compared with the result of human visual system. Furthermore, a perceptional evaluation method and its conditions were established.

P-143

Distortionless Optimal Stereoscopic Image Condition Considering General Viewing Distance in the TV ConditionD.-W. Kim, K.-H. Lee (KIST, Korea), E.-Y. Chang (ETRI, Korea), and S.-K. Kim (KIST, Korea)Large distortion is made by toed-in camera configuration in the TV condition that has short viewing distance, when the gaze position of a stereoscopic image coincides with that of real space. Therefore, in the TV condition, we confirmed that the proper camera configuration is the modified parallel configuration, and found distortionless optimal stereoscopic image condition using this camera configuration.

P-144

The Correct Depth Representation in Displayed Space at StereoscopyK.-H. Lee, D.-W. Kim (KIST, Korea), S.-H. Kim (Konkuk Univ., Korea), N. Hur (ETRI, Korea), and S.-K. Kim (KIST, Korea)We proposed the method to present corrected depth cue to an observer by stereoscopic display. It was performed in sequence that designing the displayed space having a constant interval of depth and then defining the object space which had considered to an environment of display and based on computer graphics. Consequently, we had performed a different process of reported existing methods distinctively and …

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P-145

LED Scanning Backlight Stereoscopic Display with Shutter GlassesJ.-C. Liou, K. Lee (ITRI, Taiwan), and F.-G. Tseng (Nat′l Tsing Hua Univ., Taiwan)LED Scanning Backlight Stereoscopic Display with Shutter Glasses is provided to realize stereoscopic image viewing even in a liquid crystal display. The eye shutter signal is alternately switched from the left eye to the right eye with 120Hz of LCD Vertical synchronization(V-sync)

P-146

Three-dimensional Integral Imaging using an Elastic PDMS Lens ArrayY. Kim, Y.-T. Kim, J.-H. Jung, S.-D. Lee, and B. Lee (Seoul Nat′l Univ., Korea)In this paper, we propose a three-dimensional (3D) integral imaging system using an elastic lens array instead of conventional rigid lens array. The lens array is made of polydimethylsiloxane (PDMS) that is optically transparent and flexible material. We can stretch the PDMS lens array to be expanded into a certain extent, and control the lens pitch of the system easily. That flexible design enables a fine 3D integral imaging display.

P-147

Computational Integral Imaging with Enhanced Depth SensitivityG. Baasantseren, J.-H. Park, and N. Kim (Chungbuk Nat′l Univ., Korea)Novel computational integral imaging technique with enhanced depth sensitivity is proposed. For each lateral position at a given depth plane, the dissimilarity between corresponding pixels of the elemental images is measured and used as a suppressing factor for that position. Experimental and simulation results show that reconstructed depth image on the incorrect depth plane is effectively suppressed.

P-148

Efficient Generation of CGH using Statistical Redundancy of 3-D ImagesS.-C. Kim and E.-S. Kim (Kwangwoon Univ., Korea)In this paper, we propose a new approach for fast generation of CGHs of a 3-D object by using the runlength encoding and N-LUT methods. In this approach, object points to be involved in calculation of the CGH pattern can be dramatically reduced and as a result a significant increase of computational speed can be obtained

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Computational Integral Imaging Reconstruction by use of Scale-variant Magnification TechniqueD.-H. Shin and H. Yoo (Dongseo Univ., Korea)In this paper, we present an interference problem among elemental images in computational integral imaging reconstruction. To overcome the interference problem, we propose a method to calculate a minimum magnification factor and the preliminary experiments are performed.

P-150

Computational Integral Imaging Reconstruction of 3D Object using a Depth Conversion TechniqueC. Tan, D.-H. Shin, B.-G. Lee (Dongseo Univ., Korea), and E.-S. Kim (Kwangwoon Univ., Korea)In this paper, a novel CII method using a depth conversion technique is proposed. The proposed method can move a far 3D object near lenslet array and reduce the computation cost dramatically. To show the usefulness of the proposed method, we carry out the preliminary experiment and its results are presented.

P-151

Continuous Depth Expression in Double-Layer 3D DisplayY. Kim and J.-W. Seo (Hongik Univ., Korea)A method to make the near and far images for a double layer 3D display system to create continuous depth illusion has been studied. The luminance ratio between the near and far images should be allocated based on the tone reproduction characteristics of the display systems.

P-152

Efficient Search Algorithm for Fast Motion EstimationD.-M. Park, T.-I. Kwak, B.-H. Hwang, J.-H. Yun, and M.-R. Choi (Hanyang Univ., Korea)Block-matching motion estimation plays an important role in video coding. In this paper, we propose an Efficient Search Algorithm for Fast Motion Estimation. The proposed algorithm detects motion variation for reducing computational complexity before determining motion vector. Experimental results show that the proposed algorithm has good performance than conventional algorithms through quantitative evaluation

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A Tone Mapping Method by Local Contrast and Detail Enhancement for High Dynamic Range ImagesB.-Y. Kim, B.-H. Hwang, J.-H. Yun, and M.-R. Choi (Hanyang Univ., Korea)In this paper, tone mapping method by local contrast and detail enhancement for High Dynamic Range (HDR) is proposed. By applying Piecewise Dynamic Range Histogram Adjustment (PDRHA) and Detail Enhancement Volume (DEV) with decomposed layers, tone mapping is performed effectively. The experimental results show that the proposed method preserves local contrast and overall impression with naturalness of original images.

P-154

Bright Surround Luminance and Perceived Image ContrastA. Kim, H. S. Kim, S. O. Park, Y. S. Baek (Daejin Univ., Korea), and Y. J. Kim (Univ. of Leeds, UK)The theory of Bartleson and Breneman that the perceived image contrast changes with surround luminance (the lighter surround provides higher contrast) was tested an over bright condition (8500cd/m2). Contrarily to the Bartleson and greneman′s results, we observed the fact that perceived contrast was decreased when surround luminance increxsed from dark to over bright through two sets of psychcphysical experiments based upon both uniform gray patches and complex color images.

P-155

Enhanced Cross Search Algorithm using Predicted Motion Vector for Fast Block Motion EstimationB.-K. Ko, T.-I. Kwak, B.-H. Hwang, J.-H. Yun, and M.-R. Choi (Hanyang Univ., Korea)Various Motion Estimation (ME) algorithms have been proposed since ME requires large computational complexity. The proposed algorithm employs Enhanced Cross Search Pattern (ECSP) using motion vector of neighbor-blocks to search the motion vector. The experimental results show that proposed algorithm reduces the search point up to 35% compared to conventional methods.

P-156

Redefinition of Viewing Angle Image Quality in LCDsJ.-Y. Ahn, D.-W. Kang, S.-A. Park, K.-H. Shin, J.-W. Moon, M. Lim, and H.-H. Shin (LG Display Co., Ltd., Korea)We analyzed the problem of the typical definition of the viewing angle, where the contrast ratio is higher than 1:10 and suggest the new definition of the viewing angle by considering the contrast ratio, color shift, luminance and gamma shift in the viewing direction all together.

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Viewing Quality Enhancement of 3D Reconstructed Images in Computational Integral Imaging Reconstruction by Use of Averaging MethodG. Li, D.-C. Hwang, K.-J. Lee, and E.-S. Kim (Kwangwoon Univ., Korea)In this paper, an improved computational integral imaging reconstruction (CIIR) is proposed. The proposed method can highly enhance the viewing quality of reconstructed image. To show the feasibility of proposed method, some experiments are performed and the results are compared and discussed with those of the conventional method

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Recognition of Partially Occluded 3-D Targets from Computationally Reconstructed Integral ImagesK.-J. Lee, G. Li, G.-S. Lee, D.-C. Hwang, and E.-S. Kim (Kwangwoon Univ., Korea)In this paper, a novel approach for robust recognition of partially occluded 3-D target objects from computationally reconstructed integral images is proposed. The occluding object noises are selectively removed from the picked-up elemental images and performance of the proposed integral imaging-based 3- D target recognition system can be improved.

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Analysis of Eye Response to Low Brightness 3D Displays and Increase Brightness in 3D RPTV using Long Life, High Power DPR SystemK. Li (Wavien, Inc., USA)3D displays requires multiplexing of left and right pictures on the same screen so that they can be viewed independently by the view using various schemes, including LCD shutters, polarizers, narrow band filters, and lenticular lenses on the screen. All these methods reduce the effective screen brightness by as much as 10X. The eye responses to the lower brightness are analyzed and found to compensate partially giving a lower perceived brightness. This paper presents such eye response analysis and a low cost approach to increasing brightness in a RPTV using the long life DPR system, increasing the screen brightness by …

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The Realization of 3D Display by using 2D SensorK.-T. Lee, K.-T. Um, S.-J. Kim, and K.-P. Chae (LG Components R&D Center, Korea)To make 3D camera system, we check the possibility of advanced range camera module based on measuring the time delay of modulated infrared light , using a single detector chip fabricated on standard CMOS process. To depth information, electronic shutter and interlaced scanning method of 2D sensor is needed. Especially, we design “lens system, illumination unit” and review simulation result.

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An Optical Feedback System for 2D Dimming RGB LED BacklightT.-W. Lee, J.-H. Lee, C.-G. Kim, and S.-H. Kang (LG Display Co., Ltd., Korea)For several years, many researchers have proposed LED backlight dimming technology for low power consumption and high contrast ratio. One of the major issues plaguing RGB LED with 2D dimming technology is color shift. This undesirable variation makes it difficult to use RGB LED as light sources in the backlight system. This paper describes the useful method of the optical feedback system for 2D dimming RGB LED backlight. The test results show that our proposed method is very suitable for the 2D dimming technology.

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Novel In-cell Retarder Materials for Transflective IPS-LCDsS. Sekiguchi, A. Kishioka, J. Tanaka, M. Teramoto, T. Hamamoto, and J. Tanno (Hitachi Displays, Ltd., Japan)We have developed new in-cell retarder materials that provide good transmittance and resolution with the goal of enhancing the properties of transflective IPS-LCDs. We explored various additive surfactants to optimize the applicability of the materials. Moreover, we selected photopolymerization initiators and liquid crystal diacrylate monomers as negative-type photo-patternable retarder materials, seeking to improve resolution and transmittance.

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New Invisible Effective IR-Phosphor in the Basis of the Ytterbium OrthophosphateO. Y. Manashirov, B. M. Sinelnikov (North-Caucasus State Technical Univ., Russia), and V. A. Vorobiev (Laboratory of Nanochemistry and Nanotechnology SSCRAS, Russia)

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Energy Reduction in LCD DisplaysT. Liu, M. O′Neill, K. M. Hoffman, Q. D. Sanford, A. M. Serres, and R. Schiller (3M Company, USA)Low-loss optical films can be used in LCD backlights to improve the display efficiency. Improvements can be used to enhance display performance, increase functionality and reduce energy costs.

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Synthesis and Luminescent Properties of Eu3+-doped YVO4 by using a Mild Hydrothermal ProcessY.-M. Moon, S. Choi (KRICT, Korea), S. H. Lim (Korea Univ., Korea), and H.-K. Jung (KRICT, Korea)Nanoscale YVO4:Eu3+ phosphor has been synthesized by a mild hydrothermal reaction at various experimental conditions. The particle and luminescent properties of nanophosphors were characterized with X-ray diffraction, electron microscopy and photoluminescence. It has been found that pH value play a key factor both controlling particle size and luminous efficiency.

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Photoluminescence Property of ZnO Nanoparticle Prepared by Microwave Irradiation MethodN. Sakamoto, S. Ishizuka, N. Wakiya, and H. Suzuki (Shizuoka Univ., Japan)ZnO nanoparticle was successfully prepared by microwave irradiation method in various oxygen/nitrogen ratio atmospheres. The product prepared in a low oxygen ratio atmosphere showed tetra pod shape with high aspect ratio, c/a. PL spectra of the products showed higher UV emission intensity than the others when it was prepared in the atmosphere oxygen/nitrogen=40/60.

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Electro-optical Characteristics of External Electrode Fluorescent Lamp Depending on Gas Pressure and Mixing RatioH. D. Kim, H. W. Jeon, C. H. Lee, J. H. Yoon, J. B. Kim, J. H. Lim, J. K. Shin, and I. J. Chung (LG Display Co., Ltd., Korea)We investigated influence of gas pressure and mixing ratio on the electro-optical properties of External Electrode Fluorescent Lamp (EEFL). The experimental results indicated that luminance and efficiency became the maximum at lower gas pressure and Ar mixing ratio.

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Discharge Characteristics of a Flat Plasma Backlight with Long Electrode GapQ. Li, Y. Luo, Y. Zheng, L. Yang, Y. Cui, J. Liu, Z. Zhang, and H. Tolner (Southeast Univ., China)The discharge characteristics of a flat plasma backlight with long electrode gap are investigated. The effect of operating voltage and repetition rate on brightness and luminance efficiency is investigated. A new high efficacy mode is found at low frequencies around 15-40 KHz; a lumen efficacy of 15.3 lm/W is achieved at a luminance of 2400 cd/m2. In the high brightness mode, present at high voltage, we find a maximum luminance of 5900 cd/m2 at 30KHz.

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Cu-based Ink-jet Printable Inks for Highly Conductive Patterns at Lower TemperatureK. Woo, D. Kim, and J. Moon (Yonsei Univ., Korea)The metal films ink-jetted using the conductive ink based on a mixture of copper and silver nanoparticles were investigated. The porosity and resistivity of films were minimized by adjusting the mixing ratio of Cu and Ag nanoparticles. We demonstrated that the printed tracks with good conductivity could be obtained at sufficiently lower annealing temperatures where plastic substrates could be used.

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Analysis of CCFL Blackening in Edge-lit LCD ModulesY. Lee, D. Seo, C. Noh, and S. Choi (Samsung Electronics Co., Ltd., Korea)For the life estimation of CCFLs in edge-lit LCD modules has been required CCFL blackening test, which is executed in the state of low current and long-time operation under the high temperature condition. We investigated the reason why CCFL blackening happened more easily in the above test conditions and the way how mechanical parts had influence upon CCFL blackening in the edge-lit LCD modules.

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Ink-jet Printed Oxide Semiconductor TransistorsY. Jeong, D. Kim, and J. Moon (Yonsei Univ., Korea)We studied ink-jet printing for selective deposition of soluble oxide semiconductor to fabricate transistor. Sol-gel derived ZTO solution was synthesized for ink-jet printable solution. Transistors were produced by printing oxide layer between ITO electrodes. We demonstrated that ink-jet printed ZTO transistors work well and surface treatment significantly influences device performance.

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Improvements of the Luminous Efficiency of Mercury-free Fluorescent lamps via Structural and Complex Gas Mixture ChangesB. J. Oh, J. C. Jung, I. W. Seo, H. Kim, and K.-W. Whang (Seoul Nat′l Univ., Korea)Structural parameter variation effects (changing the coplanar gap under different discharge dimensions) and use of complex gas mixtures (He, Ne, Ar and Xe) in mercury-free fluorescent lamps are studied in this paper. Pure Neon gas is the best buffer gas for obtaining high luminous efficiency in mercury-free fluorescent lamps. It is shown that with a shorter coplanar gap (30mm), a high luminous efficiency can be obtained at low operating voltage, as well as high luminance uniformity and stable discharge with a Ne-Xe 20% gas mixture.

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Highly Conductive and Transparent Electrodes for the Application of AM-OLED DisplayM. K. Ryu, S.-H. K. Park, C.-S. Hwang, J.-h. Shin, W.-S. Cheong, D. Cho, S. H. Yang, C.-W. Byun, J.-I. Lee, S. M. Chung, S.-M. Yoon, H. Y. Chu, and K. I. Cho (ETRI, Korea)We prepared highly transparent and conductive Oxide/Metal/Oxide(OMO) multilayer by sputtering and developed wet etching process of OMO with a clear edge shape for the first time. The transmittance and sheet- resistance of the OMO are about 89% and 3.3 Ω/sq., respectively. We adopted OMO as a gate electrode of transparent TFT (TTFT) array and integrated OLED on top of the TTFT to result in high aperture ratio of bottom emission AM-OLED.

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Synthesis of Imide Monomers for Application to Organic Photosensitive Interdielectric LayerH.-Y. Kwon, Q. H. Vu, Y.-S. Lee, and L. S. Park (Kyungpook Nat′l Univ., Korea)A negative photoresist formulation was developed utilizing synthesized UV monomers containing imide linkage, photoinitiator, UV oligomer, and alkali developable polymer matrix. It was found that via-holes with good resolution, high transmittance and thermal resistance could be obtained by photolithographic process utilizing the negative-type photoresist formulations.

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Synthesis and Characterization of 6,13-Disubstituted Pentacene DerivativesH.-G. Kim, E.-J. Choi (Kumoh Nat′l Inst. of Tech., Korea), J.-H. Park, and J.-H. Kim (Hanyang Univ., Korea)Pentacene has excellent semi-conducting characteristics. But pentacene practically used in OTFTs gives rise to problems mainly due to its sensitivity to oxygen and its very low solubility. In order to make up the problems, 6,13-disubstituted pentacene derivative was synthesized and characterized. The properties of the compound were characterized by FT-IR, NMR and we measured the charge transport mobility and the on/off current ratios.

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Thermal Properties of Phosphate Glass with Additives for Barrier-ribs in Plasma Display PanelC. Lee, D. Kim (Inha Univ., Korea), Y. You, S. Lee (Phoenix PDE Corp., Korea), S. Hwang, and H. Kim (Inha Univ., Korea)Phosphate glass added the various alkali additives is one of the substitutive materials for the barrier-ribs in plasma display panel. The results of differential thermal analysis and coefficient of thermal expansion show that the alkali oxides affect the thermal properties of phosphate glass.

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Scanning of Mercury-free Flat Fluorescent Lamp(MFFL) for LCD BacklightI. W. Seo, J.-C. Jung, B. J. Oh, H. Kim, and K.-W. Whang (Seoul Nat′l Univ., Korea)We proposed a new Mercury-free flat fluorescent lamp (MFFL) for LCD backlight which has the scanning ability to reduce the blurring edges of moving images. We expanded the single cell MFFL with 2.2 inch diagonal size into the multi-cell MFFL for the 32-inch LCD-TV backlight application, and examined its response characteristics and proposed a driving scheme for scanning.

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Wet Etching Behaviors of Transparent Conducting Ga- doped Zinc Oxide Thin Film by Organic Acid SolutionsD.-K. Lee (Hongik Univ., Korea), S. J. Lee, J. Bang (LG Chem. Ltd., Korea), and H. Yang (Hongik Univ., Korea)150 nm thick Ga-doped ZnO thin film, which was deposited by a sputtering process, was wet-chemically etched by using various organic acids such as oxalic, citric and formic acid. Wet etch parameters including etchant concentration and temperature are investigated for each etchant, and their effects on the etch rate and the feature of edge line are compared.

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Patterning of Conducting Polymer at Micro-scale using a Selective Surface TreatmentK.-H. Lee, S.-M. Kim, K.-S. Kim, S. Song, E.-U. Kim, H. Jung, J. J. Kim, and G.-Y. Jung (GIST, Korea)We demonstrated micro-scale conducting polymer patterning based on a selective surface treatment. A substrate with a patterned photoresist was immersed into OTS (Octadecyltrichlosilnae) solution. The protected substrate areas were hydrophilic after removing the PR resist, where a conducting polymer solution was coated selectivly by spin-coating method.

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A New Approach to the Current Regulator Design of LED Strings based on Current MirrorP.-J. Kim, M.-K. Yoo, R.-H. Lee, K.-H. Lee, K.-K. Jang, and S.-H. Kang (LG Display Co., Ltd., Korea)This paper studies the current regulator of LED Backlighting system for LCD. The proposed regulator and a typical regulator are introduced. To find out the characteristics of two regulators, Prototype samples of LED Backlighting system are made. Both the proposed regulator and a typical regulator are compared with electrical, thermal and optical characteristics each viewpoint

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High Mobility Single-Crystal OTFTs based on TIPS Anthracene DerivativesJ.-W. Park (Gyeongsang Nat′l Univ., Korea), D. S. Chung (POSTECH, Korea), D. M. Kang, Y.-H. Kim (Gyeongsang Nat′l Univ., Korea), C. E. Park (POSTECH, Korea), and S.-K. Kwon (Gyeongsang Nat′l Univ., Korea)We elucidated a way to increase the mobility of π- stacked materials by comparing various single-crystal OFETs. A high field-effect mobility (of 3.7 cm2/Vs) was obtained by increasing the effective π-stacking area and decreasing the π-stacking distance.

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Synthesis and Characterization of a New p-type Amorphous Conjugated Copolymer for Solution Process OTFT MaterialJ. U. Ju, P. T. Kang (Gyeongsang Nat′l Univ., Korea), D. S. Chung (POSTECH, Korea), Y.-H. Kim (Gyeongsang Nat′l Univ., Korea), C. E. Park (POSTECH, Korea), and S.-K. Kwon (Gyeongsang Nat′l Univ., Korea)A new p-type conjugated copolymer, poly(9,10-diethynylanthracene-alt-9,9- didodecylfluorene(PDADF) was synthesized through a Sonogashira coupling reaction. A solution-processed thin film transistor device showed a carrier mobility value of 6.0 × 10-4 cm2/Vs with a threshold voltage of -17 V and a capacitance (Ci) of 10 nF/cm2.

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Synthesis, Application of Thermally Stable Red Dyes for LCD Colorfilter; Influence of Dye Structures on the Aggregation Properties in the Film StateC. Sakong, Y. D. Kim, and J. P. Kim (Seoul Nat′l Univ., Korea)Three thermally stable red dyes of azo, quinacridone and perylene derivatives were synthesized and dye-based color filters were manufactured for liquid crystal display. Aggregation behavior of the dyes and their spectral property in film state were investigated by concentration dependent spectroscopy and field emission scanning electron microscopy (FE-SEM). These dyes have remarkable difference on their aggregation behavior in film state. …

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Improvement of Slit Photolithography Process Reliability for Four-Mask Fabrication Process in TFT LCDsT.-Y. Min, H. Qiu, Z. Wang, W. Gao, S.-U. Choi, and S.-K. Lee (Beijing BOE Optoelectronics Tech. Co., Ltd., Korea)In order to reduce the manufacturing cost of TFT LCDs and cut down an amount facilities invested, there are many LCD panel makers contributes to convert the current Five-mask manufacturing process into the noble Four-mask fabrication process. We optimized the slit mask to improve the poor process reliability.

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Qualification of Liquid Crystal Mixtures by Bulk-state Transient Current AnalysisK.-Y. Peng, H.-M. Yin, Y.-C. Lin, Y.-L. Wang, L.-W. Kung, M.-X. Chan, H.-A. Cheng, W.-L. Liau, and A. Lien (AUO, China)Transient current (TC) on bulk-state liquid crystal mixtures was measured. We found that TC is very sensitive to impurities and the features of TC curves depend on the type of contamination, from which the quality of materials can be definitely evaluated and the type of impurities can also be revealed.

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High Spatial Resolution Optical Characterization of LCDs and Their ComponentsP. Boher, T. Bignon, and T. Leroux (ELDIM, France)We present a new tool to measure precisely the emissive properties of displays at the pixel level with submicrometric spatial resolution. It is useful to check the technological defects and their impact on the emissive properties of the displays. Backlight films and transflective and reflective displays are measured.

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A Compacted In-line Wet Etch/Cleaning System with a Reverse Moving Control SystemS. H. Im, E. S. Cho, and S. J. Kwon (Kyungwon Univ., Korea)For the cost reduction in the fabrication of display panels, a reverse moving system was equipped to a compacted in-line wet etch/cleaning system. For the effect of the alternating movement of substrate on the wet etch process, ITO layers were etched in various moving modes of substrates and the results were compared and analyzed.

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The Improvement of the Off-Current Characteristics in the Short Channel a-Si:H TFTsJ. H. Bang, Y. K. Ahn, W. S. Ryu, J. O. Kim, Y. K. Kang, J. Y. Yang, M. S. Yang, I. B. Kang, and I. J. Chung (LG Display Co., Ltd., Korea)We have investigated the effects of hydrogen plasma treatment by PECVD (Plasma Enhanced Chemical Vapor Deposition) in the back channel region, the method for reducing the off state leakage current which increases with the short channel length of a-Si:H TFTs. To improve the off current characteristics, we analyzed the hydrogen plasma treatment with various RF power and plasma treatment times of PECVD. As the result of hydrogen plasma treatment in the back channel region it was remarkably reduced the off current level of 2um channel length TFT.

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Long Period Application of AC Field Causing Contrast Reduction of IPS CellY. Momoi (LG Display Co., Ltd., Japan) and T. Koda (LG Display Co., Ltd., Japan)It is known that AC electric field to drive IPS mode of liquid crystal display (LCD) causes reduction of the contrast after long period of display operation. Our results are presented in this paper on a base of a model of interaction between surface of PI alignment film and LC molecules. …

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Alignment System Development for Producing OLED using Fourth-generation SubstrateJ.-Y. Park, S.-Y. Han, N.-H. Lee, J.-O. Choi, and H.-S. Shin (Doosan Mecatec Co., Ltd., Korea)Doosan Mecatec has developed alignment system for Organic Light- Emitting Diode (OLED) display production using large size substrate. In the present article, The alignment system between the substrate and the mask, which is a core technology for producing the OLED product using the fourth-generation substrate with 730×920mm2 or more, will be described by dividing into a substrate loader, a magnet unit, …

P-191

Study on Orientation Distribution of Discotic Liquid Crystal in Compensating Film for Viewing Angle Improvement of Liquid Crystal DisplaysJ. W. Ryu, Y. S. Shin (Ajou Univ., Korea), Y. K. Kim (Samsung Advanced Tech. Training Inst., Korea), and S. Y. Kim (Ajou Univ., Korea)The discotic liquid crystal used for the viewing angle improvement of the twist nematic liquid crystal display panel in compensating film is analyzed. For the optical properties of the compensating film, we measured the polarization state of the light passing through the compensating film as the tilt angle and the azimuth angle of the film were varied, and then we compared the measured polarization state to the calculated one. …

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Electro-controllable Omni-directional Laser Emissions from a Helical Polymeric Network Composite FilmW. Jang (KOPTI, Korea), B. Park, M. Kim, S. W. Kim, Y. Kim, E. H. Choi, Y. H. Seo, G. S. Cho, S. O. Kang (Kwangwoon Univ., Korea), and H. Takezoe (Tokyo Inst. of Tech., Japan)In optical information technology, an electro-controllable Photonic Band Gap (PBG) in a photonic crystal (PC) material is potentially useful for the manipulation of light.1-4 Despite a great deal of research on PBGs, the reliable use of electro-active PBG material systems is restricted to only a few cases because of the complex and limiting nature of the structures involved. …

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2D Slab Silicon Photonic Crystal for Enhancement of Light Emission in Visible WavelengthsY. Cui and J.-B. Lee (Univ. of Texas at Dallas, USA)We present 2D slab silicon-based photonic crystal optical insulator to enhance light emission efficiency of light-emitting diode (LED). A 2D slab silicon photonic crystal is designed in such a way that light emitting diode die can be placed in the middle of the silicon photonic crystal. The device creates light propagation forbidden region in horizontal plane for Transverse Electric (TE) light with the wavelength range of 450 nm to 600 nm.

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New Electrochromic Materials and Prevention of Cross- talk in Passive Matrix Electrochromic DisplayC. H. Noh, J. E. Jang, J. E. Jung, J. M. Lee, S. J. Jeon, R. R. Das, J. Y. Han, J. M. Kim (SAIT, Korea), S. U. Son, S. Y. Park, and W. S. A. Moustafa (Sungkyunkwan Univ., Korea)Here we describe the new structured electrochromic(EC) materials to improve the three primary colors (RGB). We also report the simply isolated electrochromic unit cell using gel type electrolyte and show cross-talk’ free driving of EC display device.

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Red-shift of the Photoluminescence Peak in N-doped ZnO PhosphorsJ. K. Kim, J. W. Lim, H. T. Kim, and S. J. Yun (ETRI, Korea)ZnO films were fabricated using rf-magnetron sputter deposition process with different N2 ambient. N-content in N-doped ZnO films was less than 1%. The wavelength of the highest intensity PL peak of N-doped ZnO was shifted to higher wavelength with increasing N2 flow rate in the deposition ambient. These results indicated that the optical property of ZnO was significantly affected by the defect level created by doping with a very small amount of N.

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Two-way Viewing Angle Switchable LCD with Two-Domain VA StructureS. P. Preman, C. P. Chen, T.-H. Yoon, and J. C. Kim (Pusan Nat′l Univ., Korea)In this paper we propose a new method for obtaining two way switchable LCD. For this two domain vertical alignment LCD is used. A two way LCD is able to show different images on the same screen based on left and right perspectives. Viewing angle dependence of different grey levels of transmittance for the polar angles 0, +45 and -45 degree are also found out.