What semiconductor technologies support active circuits above 100 GHz?
Semiconductor Device Technologies for Sub-THz and THz Circuits
Active circuits above 100 GHz demand transistor technologies with fmax several times higher than the operating frequency.
| Parameter | Option A | Option B | Option C |
|---|---|---|---|
| Performance | High | Medium | Low |
| Cost | High | Low | Medium |
| Complexity | High | Low | Medium |
| Bandwidth | Narrow | Wide | Moderate |
| Typical Use | Lab/military | Consumer | Industrial |
Technical Considerations
InP HEMT transistors with 25-50 nm gate length achieve fmax above 1.5 THz. Noise figures of 2-3 dB at 100 GHz, 4-6 dB at 200 GHz, and 8-12 dB at 300 GHz.
Performance Analysis
InP HBTs offer fmax exceeding 1 THz. Excellent device uniformity for high-speed DACs, ADCs, and multiplexers at 100+ Gbaud.
Design Guidelines
SiGe HBTs in 130nm and 55nm processes achieve fmax of 500-700 GHz. CMOS co-integration enables highly integrated single-chip transceivers. SiGe transceivers demonstrated at 240 GHz.
- Performance verification: confirm specifications against the application requirements before finalizing the design
- Environmental factors: temperature range, humidity, and vibration affect long-term reliability and parameter drift
- Cost vs. performance: evaluate whether the application demands premium components or standard commercial grades
- Interface compatibility: verify impedance, connector type, and mechanical form factor match the system architecture
Implementation Notes
GaN on SiC delivers the highest output power above 100 GHz. At 94 GHz, GaN PAs produce 1+ watts. At 140 GHz, 100+ mW has been demonstrated.
Frequently Asked Questions
Which technology is best for a 140 GHz transceiver?
InP HEMT or HBT provides the best RF performance. SiGe BiCMOS offers a lower-cost alternative with adequate performance when digital integration is important.
Can standard CMOS work at D-band frequencies?
Advanced CMOS can build basic oscillators and detectors at 100-300 GHz, but fmax limitations prevent useful amplifier gain.
What foundries offer InP MMIC fabrication?
Northrop Grumman, HRL Laboratories, Teledyne Scientific (HBT), WIN Semiconductors, OMMIC, and Fraunhofer IAF.