Upload
others
View
3
Download
0
Embed Size (px)
Citation preview
Sub-THz Wireless Communication & Sensing – A Perspective on Device, Circuit, and System
Hua Wang
Associate Professor
School of ECE, Georgia Tech
Ned Cahoon
RF Business Development
GLOBALFOUNDRIES
Anirban Bandyopadhyay
RF Business Development
GLOBALFOUNDRIES
Outline
• Overview of a few Sub-THz applications and Technical challenges
• Status of Power Amplifier capabilities on different Semiconductor platforms
• Examples of System level performance for different sub-THz applications
• State-of-the-art capabilities of different Silicon Technologies and roadmap
• Summary
System Applications in Sub-THz Frequency Bands
• Imaging [T. Chi, et al, ISSCC, 2017.]
Super High Resolution and Hyperspectral
• Spectroscopy
High Sensitivity and Molecular Signature
• Communication [S. Lee, et al, ISSCC, 2019.]
Extremely High Data-Rate
• Radar
Super High Resolution and 3D Imaging
[C. Wang, et al, ISSCC, 2017.]
16 QAM / 80Gb/s
GHz
EVM=12% rms
[J. Grzyb, et al, TTST, 2016.]
Major Technical Challenges
• Challenge 1
Signal Propagation: Path loss at sub-THz
• Challenge 2
Device Capabilities: Limited gain, power density, Pout, and NF
• Challenge 3
Array Pitch Size: Small element pitch for 2D arrays (λ/2=625µm at 240GHz)
• Challenge 4
Systems/Circuits: Limited gain, power density, freq. Nonlinear circuits
Array, Lens or
“Powerful” Devices
Performance/
Functionalities
vs. Integration
Energy Efficiency
vs. Spectrum
Efficiency
vs. Spectrum BW
H. Wang, et al., "Power Amplifiers Performance Survey 2000-Present," [Online]. Available: https://gems.ece.gatech.edu/PA_survey.html
Power Amplifier Survey (2000-present) by Georgia Tech GEMS Group
-30
-20
-10
0
10
20
30
40
50
60
0.1 1 10 100 1000
Psa
t (d
Bm
)
(Log) Frequency (GHz)
Saturated Output Power vs. Frequency (All Technologies)
CMOS
SiGe
GaN
GaAs
LDMOS
InP
Oscillators
Multipliers
Johnson’s Limit
Power Amplifier Survey (2000-present) by Georgia Tech GEMS Group
-30
-20
-10
0
10
20
30
40
50
60
0.1 1 10 100 1000
Psa
t (d
Bm
)
(Log) Frequency (GHz)
Saturated Output Power vs. Frequency (All Technologies)
CMOS
SiGe
GaN
GaAs
LDMOS
InP
Oscillators
Multipliers
GaN 150nm
(Fmax=110GHz)
SiGe 130nm
(Fmax=340GHz) CMOS 45nm
(Fmax=390GHz)
InP 250nm
(Fmax=750GHz)
H. Wang, et al., "Power Amplifiers Performance Survey 2000-Present," [Online]. Available: https://gems.ece.gatech.edu/PA_survey.html
0
10
20
30
40
50
60
0.1 1 10 100 1000
Psa
t (dB
m)
Frequency (GHz)
Saturated Output Power vs. Frequency (All Technologies)
CMOS
SiGe
GaN
InP
InP 250nm
(Fmax=750GHz)
SiGe 130nm
(Fmax=220GHz)
CMOS 45nm
(Fmax=280GHz)
GaN 150nm
(Fmax=110GHz)
• Output power vs. frequency
• Power generation scheme vs. frequency
• Power amplifiers and Fundamental
Oscillators (~200GHz)
• Multipliers and Harmonic Oscillators
(~500GHz and above)
Power Amplifier Survey (2000-present) by Georgia Tech GEMS Group
-30
-20
-10
0
10
20
30
40
10 100 1000
Psa
t (d
Bm
)
(Log) Frequency (GHz)
CMOS Power Amplifiers SiGe Power Amplifiers
Oscillators Multipliers
Johnson’s Limit
H. Wang, et al., "Power Amplifiers Performance Survey 2000-Present," [Online]. Available: https://gems.ece.gatech.edu/PA_survey.html
fT and fmax of Existing Device Technologies
Teledyne InP 130nm(fmax=1.1THz)
Teledyne InP 250nm(fmax=750GHz)
Keysight InP 500nm(fmax=550GHz)
Qorvo GaN 150nm(fmax=110GHz)
III-V Technology
𝑓𝑇 =𝑔𝑚
2𝜋𝐶𝑔𝑔• fT cut-off frequency: Transistor short-circuit ac current gain falls to 1
Switching circuits MUX/dividers and low noise circuit LNA
• fmax max oscillation frequency: Transistor maximum unilateral power
gain falls to 1 Power amplifiers, LNAs, general amplifiers, oscillators 𝑓𝑚𝑎𝑥 ≈
𝑓𝑇8𝜋𝑅𝑔𝐶𝑔𝑑
• Amplifier design Rule of Thumb: Frequency f<fmax/2 with ~6dB gain for perfectly neutralized devices
Squeezing More Power Gain from Devices
[H. Bameri, et al, “A High-Gain mm-Wave Amplifier Design: An Analytical Approach to Power Gain Boosting,” JSSC, 2017.]
[S.J. Mason, et al, “S.J. Mason, “Power Gain in Feedback Amplifier,” Transactions of the IRE Professional Group on Circuit Theory, 1954.]
𝐺𝑚𝑎 =Y21Y12
(K − K2 − 1)
Maximum available gain:
Maximum stable gain(stabilized device, K=1):
𝐺𝑚𝑠 =Y21Y12
K =2𝑅𝑒 Y11 𝑅𝑒 Y22 − 𝑅𝑒 Y12Y21
|Y12Y21|
Stability factor:
Unilateral power gain(U):
=𝑌21′ 2
4[𝑅𝑒 𝑌11′ 𝑅𝑒 𝑌22
′ ]
𝑈 =Y21 − Y12
2
4[𝑅𝑒 Y11 𝑅𝑒 Y22 − 𝑅𝑒 Y12 𝑅𝑒 Y21 ]
Maximum achievable gain:
𝐺𝑚𝑎𝑥 = 2𝑈 − 1 + 2 𝑈(𝑈 − 1) ≈ 4𝑈
Input
Network
Output
Network
Unilateralized Network
Input
Network
Output
Network
Embedded Network
Input
Network
Output
Network
Basic
Device
Neutralization
Unilateralization:
Broad Band
Embedding:
Narrow Band
Achievable Power Gain in Example CMOS Technology vs. Teledyne 250nm InP
• Device with layout and parasitics extraction
• Basic device vs. Neutralization vs. Embedding (100GHz-300GHz)
• An example CMOS technology (fmax~280GHz) vs. Teledyne 250nm InP (fmax~750GHz)
0
5
10
15
20
25
30
35
40
10 100 1000
Gai
n(d
B)
Frequency(GHz)
6dB improvement
Near-fmax regionU
Gmax
Gma/Gms
Power Gain of Example CMOS Technology Example CMOS Technology vs. 250nm InP
0
5
10
15
20
25
30
35
40
10 100 1000G
ain
(dB
)
Frequency(GHz)
UGmax
Gma/Gms
Fmax(280) (750)
GlobalFoudries 45nm CMOS SOI
Teledyne 250nm InP
Example CMOS Technology
Basic Device:
Gma/Gms
Neutralization: U
Embedding: 4×U
Applications and Systems at Sub-THz (Communication)• A 240-GHz transceiver front-end with antenna using IHP SiGe:C SiGe BiCMOS
• TX sat. Pout of -0.8 dBm with optical lens for wireless transmission over 15 cm
• 25 Gb/s BPSK with BER of 2.2×10-4.
[M. Eissa, et al, “Wideband 240-GHz Transmitter and Receiver in BiCMOS Technology With 25-Gbit/s Data Rate,” JSSC, 2018.] Leibniz-Institut für innovative Mikroelektronik, Germany
[S. Lee, et al, “An 80Gb/s 300GHz-Band Single-Chip CMOS Transceiver,” ISSCC, 2019.] Hiroshima University, Japan
• A 300GHz-Band Single-Chip CMOS Transceiver using 40nm CMOS
• Power mixer + double-rat-race 4-way combiner TX sat. Pout of -1.6dBm
• Mixer-first receiver 20dB NF
• 80Gb/s 16QAM over 3cm
Applications and Systems at Sub-THz (Communication)
• A 100GHz-300GHz Continuous-Wave
Hyperspectral Imaging Transceiver
(Globalfoundries 45nm CMOS SOI)
• Transmission mode imaging by step-motor-
controlled 2D translation stage
• Non-contact screening for food safety and 3D
printing products
• Dried and
fresh leaves• Cookie and metal
screw in a
translucent package
[T. Chi, et al, “Packaged 90-to-300GHz Transmitter and 115-to-325GHz Coherent Receiver in CMOS for Full-Band Continuous-Wave mm-Wave Hyperspectral Imaging,” ISSCC, 2017.] Georgia Tech, US
Applications and Systems at Sub-THz (Imaging)
Applications and Systems at Sub-THz (Imaging)
• TX : Broadband 90-to-300GHz distributed quadrupler (DQ)
• RX : Broadband 115-to-325GHz 4th-subharmonic mixer (SHM)
[T. Chi, et al, “Packaged 90-to-300GHz Transmitter and 115-to-325GHz Coherent Receiver in CMOS for Full-Band Continuous-Wave mm-Wave Hyperspectral Imaging,” ISSCC, 2017.] Georgia Tech, US
Applications and Systems at Sub-THz (Radar)• A 145GHz FMCW-Radar Transceiver in 28nm bulk CMOS
• High RF carrier permits greater velocity and MIMO-angular resolution
• A wide RF bandwidth of 13GHz 11mm range/depth resolution
[A. Visweswaran, et al, “A 145GHz FMCW-Radar Transceiver in 28nm CMOS,” ISSCC, 2019.] imec, Leuven, Belgium
TX path:
RX path:
Applications and Systems at Sub-THz (Spectroscopy)• A 220-to-320GHz Spectrometer for Molecular Gas Spectroscopy (65nm CMOS)
• Frequency doubler array + on-chip folded slot antenna array
• 5.2mW Radiated Power and 14.6-to-19.5dB Noise Figure
• Single frequency sweep (e.g. ~3 hours for 100GHz bandwidth)
• Simultaneous scanning using 20 comb lines
(8 minutes for 100GHz bandwidth)
[C. Wang, et al, “Rapid and Energy-Efficient Molecular Sensing Using Dual mm-Wave Combs in 65nm CMOS: A 220-to-320GHz Spectrometer with 5.2mW Radiated
Power and 14.6-to-19.5dB Noise Figure,” ISSCC, 2017.] MIT, US
Frontend Circuits at Sub-THz (Power Generation/TX)
• 215 GHz Harmonic Oscillator in TMSC 65nm CMOS
• Max dc-to-RF efficiency of 4.6% at 215 GHz and max Pout of 5.6 dBm from a
single oscillator
R. Kananizadeh and O. Momeni, "High-Power and High-Efficiency Millimeter-Wave Harmonic Oscillator Design, Exploiting Harmonic Positive Feedback in CMOS," in IEEE
Transactions on Microwave Theory and Techniques, vol. 65, no. 10, pp. 3922-3936, Oct. 2017. UC Davis, US
280µ
m
Frontend Circuits at Sub-THz (Power Geneneration/TX)• 500 GHz Sub-harmonic Oscillator in Globalfoundries 9HP SiGe
• Multi-concentric-ring structure for multi-phase injection-locking multiplier
• Max Pout of -16.6 dBm at 498 GHz with 5.1% freq. tuning and phase noise
of 87 dBc/Hz at 1 MHz offset
T. Chi, J. Luo, S. Hu and H. Wang, "A multi-phase sub-harmonic injection locking technique for bandwidth extension in silicon-based THz signal generation,"
Proceedings of the IEEE 2014 Custom Integrated Circuits Conference, San Jose, CA, 2014, pp. 1-4. Georgia Tech, US
Frontend Circuits at Sub-THz (Regenerative RX and Harmonic Oscillator TX)
Sensitivity (dBm) -89
Max Comm. Distance (cm) 50
Data Rate, Type, BER 4.4Mb/s OOK, 10-7
TX EIRP (dBm) -11.6
PDC (mW) 18.2/31.1 (TX/RX)
[T. Chi, H. Wang, M.-Y. Huang, F. F. Dai, and H. Wang, “A bidirectional lens-free digital-bits-in/-out 0.57mm2 terahertz nano-radio in CMOS with 49.3mW Peak power
consumption supporting 50cm Internet-of-Things communication,” 2018 IEEE Custom Integrated Circuits Conference (CICC), 2018.] Georgia Tech, US
• Harmonic-oscillator TX and Regenerative RX with on-chip TDC for digitized RX outputs •
• Operating at 320GHz using Globalfoundries 45nm CMOS SOI
• On-chip multi-feed slot antenna for on-antenna power combining
CMOS Cut-off Frequency fT
𝐼𝑖𝑛 =𝑉𝑖𝑛𝑍𝑖𝑛
𝐼𝑜𝑢𝑡 = 𝑔𝑚𝑉𝑖𝑛𝐼𝑜𝑢𝑡𝐼𝑖𝑛
= 𝑔𝑚𝑍𝑖𝑛 = 𝑔𝑚1
𝑗𝜔𝑇𝐶𝑖𝑛= 1
⇒ 𝜔𝑇 =𝑔𝑚𝐶𝑖𝑛
𝑓𝑇 =𝑔𝑚
2𝜋𝐶𝑔𝑔
• Transistor speed metric
• Particularly relevant for switching circuits such as MUX/DMUX, dividers, etc
• Definition: Frequency at which short-circuit ac current gain falls to 1
• CMOS fT increases with scaling
Henk M. J. Boots, Gerben Doornbos, and Anco Heringa, “Scaling of Characteristic Frequencies in RF
CMOS,” IEEE Trans. Electron Device, vol. 51, no. 12, pp. 2102-2108, Dec. 2004.
January 12, 2016 GLOBALFOUNDRIES 20
CMOS Maximum Oscillation Frequency fMAX
Conjugate match at the input:
𝑅𝑆 = 𝑅𝑔
⇒ 𝑖𝑖𝑛 = 𝑖𝑖𝑛𝑠 =𝑉𝑆2𝑅𝑔
Conjugate match at the output:𝐺𝑃 =
𝐺𝑜𝑢𝑡𝐺𝑖𝑛
=
12𝑖𝑜𝑢𝑡2 𝑅𝑜𝑢𝑡
12𝑖𝑖𝑛2 𝑅𝑖𝑛
=1
4
𝑖𝑜𝑠𝑖𝑖𝑛𝑠
2𝑅𝐿𝑅𝑔
=1
4
𝑓𝑇𝑓
2𝑅𝐿𝑅𝑔
𝐺𝑃 = 1 ⇒ 𝑓𝑚𝑎𝑥 =1
2𝑓𝑇
𝑅𝐿𝑅𝑔
∴ 𝑓𝑚𝑎𝑥=𝑓𝑇
2 𝑔𝑑𝑠𝑅𝑔 + 2𝜋𝑓𝑇𝑅𝑔𝐶𝑔𝑑𝑍𝑜𝑢𝑡 =1
𝑔𝑑𝑠 +𝑔𝑚𝐶𝑔𝑑
𝐶𝑔𝑠 + 𝐶𝑔𝑑
=1
𝑔𝑑𝑠 + 2𝜋𝑓𝑇𝐶𝑔𝑑
𝑓𝑚𝑎𝑥 ≈𝑓𝑇
8𝜋𝑅𝑔𝐶𝑔𝑑
Scaling of 𝑓𝑚𝑎𝑥depends on 𝑓𝑇, 𝑅𝑔, and 𝐶𝑔𝑑
𝑍𝑖𝑛 = 𝑅𝑔 +1
𝑗𝜔𝐶𝑔𝑠≈ 𝑅𝑔
𝑅𝐿 = 𝑍𝑜𝑢𝑡
• Transistor speed metric
• Particularly relevant for circuits that generate power such as LNA’s, PA’s,
VGA’s, etc
• Definition: Frequency at which the maximum unilateral power gain equals 1
• Parasitics have a larger impact at smaller dimensions, which limits fMAX in
advanced CMOS nodes.
M. Dehan, Characterization and modeling of SOI RF integrated components, Presses univ. de Louvain, 2003.M. Golio, The RF and MIcrowave Handbook, CRC Press Book, 2010.
January 12, 2016 GLOBALFOUNDRIES 21
CMOS fMAX peaks at ~ 450GHz
22
• Advanced nodes struggle with
gate and interconnect resistance
• Peak fMAX achieved in the 32nm
– 22nm nodes
H. J. Lee et al, “Intel 22nm FinFET (22FFL) Process Technology for RF and
mmWave Applications and Circuit Design Optimization for FinFET
Technology“, IEDM 2018
23
SiGe fT, fMAX
• fT improves with vertical scaling f • fMAX improves with reduction in
dominant parasitics
BB
T
MAXCR
ff
8
• Reduce Ccb intrinsic and extrinsic base
capacitance while maintaining low base
resistance
• Reduce Rb extrinsic and intrinsic
resistances while maintaining narrow
base width
January 12, 2016 GLOBALFOUNDRIES
Advances in SiGe have reached 500GHz fT / 700GHz fMAX
24GLOBALFOUNDRIES CONFIDENTIAL
130nm90nm55nmBipolar only
~peak fmax for SOI/CMOS
Published SiGe HBT fT, fMAX hardware results
H. Ruecker and B. Heinemann, “High Performance SiGe HBT
BiCMOS Technology”, RFIC 2018 WMM-5 Workshop
European Consortia for Advanced SiGe Development
• Four projects funded by EU for over a decade
• Significant achievement in both pushing SiGe HBT performance and BiCMOS integration
• DOT5, 2008 – 2010, 500GHz SiGe HBT
• RF2THZ, 2011 – 2014, 55nm SiGe BiCMOS
• DOT7, 2012 – 2016, 700GHz SiGe HBT
• TARANTO, 2017 – 2020, 700GHz SiGe HBT, 130-28nm SiGe BiCMOS
25
Amplifier Power and Gain at 250GHz with 500GHz SiGe
26
M. Eissa and D. Kissinger, “A
13.5dBm Fully Integrated
200-to-250GHz Power
Amplifier with a 4-Way Power
Combiner in SiGe:C
BiCMOS”, ISSCC 2019
27
Summary
• Sub-THz applications reviewed
• Communications – higher data rate
• Radar – higher resolution
• Imaging – high resolution and hyperspectral
• Spectroscopy – high sensitivity and molecular signature
• Challenges for device, circuit and systems at sub-THz frequencies
• Signal propagation and path loss at sub-THz
• Device and circuit issues – limited gain, power density, Pout, NF
• Array pitch size
• Semiconductor technology
• Higher ft/fmax technology needed for sub-THz
• fmax > 2x f application rule of thumb
• CMOS fmax limited by parasitics (gate, interconnect R) for advanced node CMOS
• SiGe demonstrated path to 500GHz/700GHz ft/fmax
• Initiatives in US and Europe for development of 700GHz SiGe BiCMOS technology