Epitaxial lateral overgrowth of thick semipolar {11$ \bar 2 $2} GaN by hydride vapor phase epitaxy

Abstract

AbstractA thick semipolar {11–22} GaN layer was grown on m ‐plane sapphire substrates by hydride vapor phase epitaxy (HVPE). We succeeded in using epitaxial lateral overgrowth (ELO) with a striped SiO2 mask to suppress crack generation, improve the flatness, and reduce the dark spot density in the semipolar {11–22} GaN layer. The ELO was performed at a growth rate of over 100 µm/h, and it was found that ELO using a SiO2 mask could be used to achieve high‐growth rate HVPE. Large hillocks were eliminated by using ELO. The dark spot density of the 2 mm {11–22} GaN layer grown by ELO was 2.7 × 107cm–2, which was one digit lower than that of a conventional GaN layer. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)