GaN growth on Si with rare-earth oxide distributed Bragg reflector structures

In this study, we prepared two types of distributed Bragg reflector structures based on Gd2O3/Si and Er2O3/Si stacks on Si(111) substrates for the growth of GaN. After determining the stability of the structures, GaN was grown in a three stage process according to the metal-organic chemical vapor deposition method. Each stage of the process was controlled mainly by the growth temperature and monitored based on in situ reflectance measurements. The samples with GaN were characterized by atomic force microscopy, X-ray diffraction, and transmission electron microscopy. These analyses demonstrated that the deposited crystalline GaN had a wurtzite structure with a smooth surface. GaN grown on a Gd2O3/Si distributed Bragg reflector had a better GaN crystalline structure than that grown on Er2O3/Si despite the lower thermal stability of the oxide. (C) 2015 Elsevier B.V. All rights reserved.