Characterization of m-GaN and a-GaN Crystallographic Planes after Being Chemically Etched in TMAH Solution oleh Nedal Al Taradeh, Eric Frayssinet, Christophe Rodriguez, Frederic Morancho, Camille Sonneville, Luong-Viet Phung, Ali Soltani, Florian Tendille, Yvon Cordier, Hassan Maher