Microstructural study of He+-implanted and thermally annealed silicon-on-sapphire layers

Abstract

The effect of He⁺ ion implantation and subsequent annealing on the silicon-on-sapphire microstructure is studied by transmission electron microscopy and X-ray diffraction analysis. It is established that He⁺ ion implantation leads to the formation of defects in the Si layer and α-Al₂O₃, while subsequent annealing causes dissociation of radiation defects in Si and formation of nanopores in α-Al₂O₃. The effect of implanted-ion dose and annealing temperature on the parameters of the porous α-Al₂O₃ layer and structural quality of the Si layer is investigated.