Gallium nitride amplifiers beyond W-band

Abstract

We have developed gallium nitride (GaN) monolithic microwave integrated circuit (MMIC) amplifiers that span different frequency ranges from Q-band (33–50 GHz) into G-band (140–220 GHz). We have designed, fabricated and tested a broadband amplifier with more than 11 dB of gain from 38 GHz to at least 110 GHz, and a broadband amplifier with gain across all of F-band (90–140 GHz) with peak gain of 18.9 dB and noise figure of 7.4 dB at 120 GHz. In G-band we have developed an amplifier with 8.7 dB small-signal gain at 149 GHz, and when two such amplifiers were placed in series, large signal power measurements gave 18.2 dBm of output RF power and 10 dB gain at 147 GHz. These results demonstrate 0.15 μm gate length GaN HEMTs are applicable for amplifiers through F-band and into G-band.