FABRICATION OF 0.2 MU-M GATE PSEUDOMORPHIC INVERTED HEMT BY PHASE-SHIFTING TECHNOLOGY

A phase-shifter edge line (PEL) mask method is applied to the gate fab rication process of InGaAs/AlGaAs pseudomorphic inverted high electron mobility transistors (HEMTs). In phase-shifting technologies, the PEL mask method suits forming a fine line pattern owing to its high resol ution. Mushroom shaped 0.2 mu m gate pseudomorphic inverted HEMTs fabr icated by using the PEL mask method show high d.c. and r.f. performanc es. As one of the applications of the 0.2 mu m gate pseudomorphic inve rted HEMTs, a decision circuit IC for 10 Gb/s optical communication sy stems is successfully fabricated.