Submillimeter wave InP-based HEMTs with fMAX over 600 GHz

In this paper we report on InP-based HEMTs with fmax of more than 600 GHz. The S-parameters of the 0.1 micron gate-length AlInAs/GalnAs/InP HEMTs were measured using on- wafer RF probes from 2 to 110 GHz. The devices have measured S21 of as high as 7 dB at 110 GHz. Using this transistor technology we have demonstrated MMICs with record gain of 30 dB for a three-stage amplifier at 140 GHz. In addition, HRL is developing next generation InP-based HEMT technology using novel AlGaPSb material system. We estimate HEMTs with fmax of more than 1 THz are possible using this material system.