Significant increase in GaN growth rate by halogen-free vapor phase epitaxy with porosity-controlled evaporator

Abstract

The GaN growth rate during halogen-free vapor phase epitaxy (HF-VPE) is significantly increased by the use of an evaporator made of a porosity-controlled TaC ceramic. A fin-shaped evaporator, which is immersed in a molten Ga source at temperatures above 1373 K, effectively pumps molten Ga by capillary action and provides a fivefold increase in the surface area of the source. This results in a 3–5 times increase in both the Ga supply rate and the GaN growth rate.