A New AlGaAs/GaAs Heterojunction FET with Insulated Gate Structure (MISSFET)

Abstract

We have proposed and successfully fabricated a new type of field-effect transistor (FET) with an M-I-S-S structure, which consists of a metal gate, an Al 2 O 3 insulator and a semiconductor-semiconductor (N-AlGaAs/GaAs) heterojunction, grown by molecular beam epitaxy. This device exhibited the following advantages. High effective mobility of electrons (µ eff being 27,000 cm 2 /V·s at 77 K) and, the capability of sustaining a high gate voltage of up to 2 V in the forward direction. These features permit the use of MISSFETs in a variety of logic circuits with a larger logic swing and higher speed than those of MESFETs.