Abstract

InP HEMT transistors using 70-nm gate length have been fabricated and modeled. Two different epitaxial structures have been tested based on either single- or composite InGaAs channel. The composite-channel HEMT exhibited significantly higher maximum transconductance, 1370 mS/mm, compared to 860 mS/mm for the single-channel HEMT whereas ft (fmax) was approximately the same, 190 (260) GHz, and 200 (320) GHz, respectively. A W-band microstrip MMIC amplifier using 70-nm gate length InP HEMT technology has been designed and fabricated for the single-channel structure. The one-stage amplifier exhibited a gain of 8 dB at 94 GHz.