Through recessed and regrowth gate technology for realizing process stability of GaN-GITs

Abstract

A new gate recess process technology has been implemented in normally off GaN based gate injection transistors (GITs) on Si substrate, in order to realize the process stability. In this process, compared to conventional recessed gate structure, the AlGaN barrier is fully removed in the gate region and then AlGaN is reproduced by epitaxial regrowth for the first time. By using this technology, standard deviation of Vth improves drastically from 229 mV to 63 mV on 6-inch substrate. And Vth is easily controlled from 1.0 to 2.3 V by changing the regrowth AlGaN thickness, without changing other DC characteristics and their distributions.