The accumulation of structural damage in AlxGa1-xN films under heavy-ion bombardment at room temperature, where x ranged from 0.05 to 0.60, was studied by means of Rutherford back-scattering/channelling spectrometry and cross-sectional transmission electron microscopy. The results showed that an increase in the Al concentration strongly enhanced dynamic annealing, and suppressed ion-beam induced amorphization. All of the wafers studied exhibited damage saturation in the bulk after high ion doses. The disorder level in the saturation regime was essentially independent of the Al content. No preferential surface disordering was observed during heavy-ion bombardment. Cross-sectional transmission electron microscopy revealed similar implantation-produced defect structures in both GaN and AlGaN.

Structural Disorder in Ion-Implanted AlxGa1–xN. S.O.Kucheyev, J.S.Williams, J.Zou, G.Li, C.Jagadish, M.O.Manasreh, M.Pophristic, S.Guo, I.T.Ferguson: Applied Physics Letters, 2002, 80[5], 787-9