Regrowth of Semipolar GaN on Nanoporous GaN Template by Metal Organic Chemical Vapor Deposition

Abstract

A nanoporous semipolar GaN template has been fabricated by photoenhanced electrochemical etching to obtain porous GaN with nanoscale pores. The surface morphology of regrown semipolar GaN on a nanoporous GaN template was enhanced by surface modification. Cross-sectional transmission electron microscopy (TEM) images showed reductions in the densities of dislocations and basal stacking faults at the regrown interface. Photoluminescence measurement also revealed that the crystallinity of regrown GaN was improved by reducing the density of defects. Our results suggest that the photoenhanced electrochemical etching and regrowth technique is promising for high-quality semipolar GaN growth with a reduced defect density on a sapphire substrate.