Efficient blocking of planar defects by prismatic stacking faults in semipolar (1122)-GaN layers on m-sapphire by epitaxial lateral overgrowth

摘要

For the next-generation solid state lighting, the production of high quality semipolar (1122) GaN layers on sapphire obtained using asymmetric epitaxial lateral overgrowth (ELO) method has been investigated. This type of ELO leads to efficient blocking of the basal stacking faults (BSFs) in the bulk, and enables the formation of nondefective layers at the surface. The BSFs terminate due to generation of prismatic stacking faults along a well defined boundary. The corresponding intensity of GaN band edge photoluminescence emission is increased by more than four orders of magnitude in comparison to that from semipolar templates.