Improvement of crystal quality of nonpolar a-plane GaN by in-situ surface modification

► The crystal quality of nonpolar a-plane GaN was improved by in-situ surface modification which was introduced by growth interruption and roughening during the growth. ► Growth interruption facilitates the enhanced adatoms diffusion length and Ga droplet assisted growth as well. ► In-situ surface modification was an effective way to improve the crystal quality and isotropy of a-plane GaN without additional ex-situ process.