Q-Band Monolithic Amplifiers

Millimeter-wave MMIC amplifiers using 0.25μm gate GaAs FET devices have achieved up to 100 mW output power and 11.5 dB small signal gain at Q-band. The two-stage circuits were fabricated using VPE and II material, and all DC bias networks were included on a 0.102" × 0.055" chip. To our knowledge, these circuits have the highest gain and power performance of MMIC amplifiers demonstrated to date above 41 GHz, without the use of external tuning adjustments. Based on discrete FET measurements, even better results are predicted for circuits fabricated with MBE material.