Impact of α-Fe2O3 Buffer Layer Growth Time on the α-Ga2O3 Grown on LiTaO3 Substrates

Corundum structured a-Ga>Oj is a promising semiconductor material for power switching devices due to its large bandgap (5.3 eV). The high dislocation density of a-Ga>0} caused by a large lattice mismatch between the a-Ga>0} and a sapphire substrate is a significant issue to a high-reliability operation. We featured LiTaOj substrates exhibiting a near corundum structure as growth substrates to decrease the lattice mismatch. Our previous study revealed that the growth of a-Ga^Oi on LiTaOj substrates required a-Fe;0; buffer layers. In this study, the impact of a-Fe;Oj buffer layer growth time on the growth of ci-Ga>0} was investigated. X-ray diffraction 28-co analysis revealed that a-Ga>0} was successfully grown by inserting ci-Fe>Ch buffer layer regardless of the buffer layer growth time. The growth time of the a-Fe>0; buffer layer affected the number of edge dislocations examined by XRD rocking curve (XRC) measurements. The smallest full width at half maximum of XRC measurements at (0006) plane of the a-Ga>0}with the buffer layer growth time of lmin was 60 arcsec. The a-Ga:0.t with the buffer layer growth time of 1 min had a smooth surface. This study contributes power switching device application of a-Ga:0.; grown on LiTaOt substrates. © 2022 Society of Materials Science Japan. All rights reserved.