Effect of implantation temperature on the H-induced microstructural damage in AlN

• We study the microstructural damage in AlN at various H-implantation temperatures.
• Study gives the understanding of surface buckling phenomena in H-implanted AlN.
• Various favorable conditions of large surface area exfoliation are proposed.

A detailed physical investigation of the H-induced microstructural damage in (0001) AlN epitaxial layers at various implantation temperatures is presented. Cross-sectional transmission electron microscopy revealed that in the case of samples implanted at 300 °C, extended defects (nanocracks) were formed only within ∼50 nm region situated below the H-concentration peak in the damage band of width ∼280 nm compared with lower implantation temperatures. This implantation temperature-dependent behavior of the microstructural damage decides the morphology of the top buckled surface. Various favorable conditions for the buckling of H-implanted surface in the form of large area exfoliation are proposed based on the present study.