0.15 mu m T-shaped gate pseudomorphic HEMT fabricated using a new optical lithographic technique

Abstract

The authors propose a new optical lithographic technique to form a 0.15 mu m length T-shaped gate. The lithographic technique is composed of PSM, low temperature PECVD of SiN, concurrent development and planarisation of the photoresist. By using this technique, a 0.15 mu m AlGaAs/InGaAs/GaAs PHEMT was successfully fabricated, and with a transconductance of 498mS/mm and cutoff frequency of 62.4GHz.