SiGe MMICs and flip-chip MICs for low-cost microwave systems

Recent Progress in SiGe device technology has improved cutoff frequencies of these devices to beyond 200 GHz. This work describes two approaches for implementing distributed structures with Si substrates: microstrip transmission lines using thick polyimide over a ground plane on the substrate (polyimide MMIC) and small Si devices or chips flip-chip mounted onto a microwave circuit board containing the distributed elements (flip-chip MIC). Microwave circuits such as amplifiers, oscillators, mixers, and frequency dividers have been demonstrated using both techniques.