John D. Cressler 9/01 1

• 21st Century Communications Market- wireless devices + computer links + transportation + space + ...

Frequency bands pushing higher

Huge market but stringent device requirements

Moral: Need High-Performance But Low-Cost Device Technology

• SiGe HBT- first bandgap-engineered Si transistor- better , VA, fT, fmax, NFmin than Si BJT- III-V performance + Si fabrication cost- 200 GHz SiGe HBTs possible!

• SiGe HBT BiCMOS Technology- SiGe HBT + best-of-breed Si CMOS- analog + digital + RF + passives for system-on-a-chip solutions- in commercial production (IBM, Maxim, TEMIC, etc.)

SiGe Technology

John D. Cressler 9/01 2

• Focus: “Next-Generation Device Technologies”

Fundamental device physics, fabrication, device and circuit characterization, RF and microwave properties of devices, profile optimization for specific circuit / system applications, device / circuit interactions, device simulation and circuit-level modeling

Research Program(John D. Cressler)

Device PhysicsSi vs SiGe vs SiC

noise, linearitybreakdown issueseffects of T, radiation

Simulationparameter models

profile optimizationmixed-mode2D / 3D

Circuits RF / MMIC analog / digital power electronics extreme environments

State-of-the-Art Hardware

• Specialties:- SiGe devices and technology

- SiC devices and technology

- radiation effects

- extreme temperatures

John D. Cressler 9/01 3

• SiGe Devices and Technology1) RF / microwave noise and linearity understanding2) Profile optimization issues, stability limits, and novel device physics phenomena3) Device-to-circuit interactions and modeling of novel device phenomena4) Radiation effects in SiGe HBT BiCMOS (total dose + SEU) 5) Breakdown limits and voltage constraints for RF circuits6) Avalanche multiplication measurement and modeling7) Understanding of 1/f noise and its up-conversion to phase noise 8) Effects of C-doping on SiGe HBTs9) Cryogenic operation

• SiC Devices and Technology1) SiC diodes for high-power / high-temperature power systems2) Effects of radiation on SiC devices and the SiO2/SiC system3) Termination modeling and design for multi-kV blocking

• Other1) Operation of SOI CMOS in extreme environments (radiation and low / high T)

• Personnel- 9 PhD, 1 MS, and 2 undergraduate students

• Funding Agents:- SRC, NSF, NASA-GSFC, IBM, NASA-CSPAE, NASA-Glenn, On Semi., JPL, TI, Rockwell

Current Research Activities(John D. Cressler)