Using ${\rm BCl}_{3}$-Based Plasma to Modify Wet-Etching Pattern Sapphire Substrate for Improving the Growth of GaN-Based LEDs

Wet-etching pattern sapphire substrates (PSS) have been used to grow GaN-based light-emitting diodes (LEDs). However, after wet etching, several sidewall facets are exposed on the patterns of PSS. These sidewall facets would grow zincblende GaN and form irregular voids. In this letter, BCl3-based plasma is used to solve this problem and improve the performance of GaN-based LEDs.