Examination of growth rate during hydride vapor phase epitaxy of GaN on ammonothermal GaN seeds

Abstract

One of the main advantages of the hydride vapor phase epitaxy (HVPE) method for crystallizing bulk gallium nitride is the crystallization of GaN with a relatively high growth rate (>100μm/h). In this paper various growth rates in the c-direction during crystallization of GaN by HVPE on ammonothermally grown GaN crystals are determined and examined. The influence of the highest (380μm/h) and the lowest (40μm/h) growth rate on the structural quality and purity of the HVPE-GaN crystals is analyzed. The optimal macroscopically stable growth rate (without cracks and pits) and the way of achieving it are presented and discussed.