An/TaN/WN/GaAs Structure Schottky Gate Formation for Self-Aligned GaAs MESFET

Abstract

An Au/TaN/WN/GaAs structure Schottky gate forming process was investigated for self-aligned microwave GaAs MESFET. Multi-layers of transition metal nitride were formed by reactive rf sputtering. Good Schottky contacts were obtained for the Au/TaN/WN/GaAs system even after a high-temperature rapid infrared lamp annealing for ion implantation. A gate forming process for self-aligned GaAs MESFET was developed using the Au/TaN/WN multi-layers gate. The self-aligned GaAs MESFET with 0.7 µm gate length showed a noise figure of 1.7 dB with an associated gain of 7.3 dB at 12 GHz.