A novel, very high breakdown voltage, field effect transistor prepared by molecular beam epitaxy

Abstract

A novel, very high breakdown voltage, field effect transistor (FET) using a camel diode structure instead of a Schottky barrier gate has been fabricated successfully by molecular beam epitaxy. The camel diode gate has several advantages over a conventional metal-electron-semiconductor FET, including elimination of metallurgical difficulties of the metal-semiconductor contact, relatively easy adjustment of built-in voltage and the potential for improving reliability in adverse environments and under high power dissipation. If the gate length is reduced to 1 microm, a transconductance in excess of 200 mS mm −1 can be expected. A significant improvement of the gate-drain breakdown voltage to 70 V has been obtained. This excellent value is superior to those reported for other GaAs FETs. Consequently, the proposed structure is suitable for high power applications.