A 17 dB gain, 0.1-70 GHz InP HEMT amplifier IC

Over the last five years, the 0.1 /spl mu/m gate length indium phosphide high electron mobility transistor (InP HEMT) has been taken from first demonstration to a high-yield, manufacturable monolithic microwave integrated circuit (MMIC) process. Discrete InP HEMT devices have shown transconductances (g/sub m/) as high as 1740 mS/mm and cutoff frequencies (f/sub T/) up to 340 GHz and thus are extremely attractive devices for high gain amplifiers in the 30-100 GHz range. For very broadband instrumentation applications, this process is used to realize a fully-integrated, three-stage, shunt-feedback amplifier with 17 dB gain from 100 MHz to 70 GHz, a gain-bandwidth product the authors believe to be the highest reported for any amplifier. In comparison to distributed amplifiers typically used for such broadband applications, this amplifier has higher gain, better low-frequency response, uses less dc power, and yet has good output power capability. Potentially low-cost MMICs of this type could open the millimeter-wave frequencies to commercial applications.<>