GaN single crystal substrate and method for processing surface of GaN single crystal substrate

摘要

The surface of a gallium nitride single crystal substrate is processed, e.g., comprising steps by planarizing the top side and the bottom side of a gallium nitride original substrate positioned on a support bed; radiating light having wavelengths ranging from 370 to 800 nanometers (nm) onto the planarized gallium nitride original substrate; measuring transmittance of the gallium nitride original substrate; and confirming whether the transmittance is within the range of 65 to 90%. A gallium nitride single crystal substrate obtained through the method of processing the surface has high transmittance ranging from 65 to 90% measured using light having wavelengths of 370 to 800 nm. The thickness ratio (DLa/DLb) of the damage layers on the both sides of the gallium nitride single crystal substrate can be obtained within the range of 0.99 to 1.01.