Low‐Pressure, Modified Halide Vapor‐Phase Epitaxy for Chemically Pure GaN Epilayers

The halide vapor‐phase epitaxy (HVPE) technique has been extensively used for the production of freestanding GaN crystals for GaN wafer manufacturing, but has had renewed interest in recent years as a technique for producing high‐quality GaN epilayers at high growth rates and without the issues of carbon incorporation which complicate the growth of GaN using metal–organic vapor phase epitaxy. Herein, thick epilayers grown by HVPE using a low‐pressure modified quartz reactor with controlled H 2 injection are presented which exhibit surface root‐mean‐square roughnesses <0.5 nm with low background doping concentrations <2E15 cm −3 and room‐temperature mobilities >1200 cm 2 V −1 s −1 . Such films are considered to be strong contenders for the production of lightly doped GaN drift layers for vertical power electronics devices.