Capacitively coupled radio frequency nitrogen plasma etch damage to N-type gallium nitride

► Characteristic of N2 plasma etch damage to n-GaN was compared with that for Ar. ► n-GaN etch damage characteristics for N2 and Ar plasmas are different. ► N2 plasma etch damage occurs independent of gas pressure. ► Although UV is emitted from N2, physical etch effect contributes to the damage. ► The surface morphology for N2 does not change from that of the as-grown sample.