Self-aligned process for emitter- and base-regrowth GaN HBTs and BJTs

Abstract

The development of a self-aligned fabrication process for small emitter contact area ( 2×4 μ m 2) GaN/AlGaN heterojunction bipolar transistors and GaN bipolar junction transistors is described. The process features dielectric-spacer sidewalls, low damage dry etching and selected-area regrowth of p-GaAs(C) on the base contact or n-GaN/AlGaN on the emitter contact. Series resistance effects are still found to influence the device performance.