Investigations on the Formation of SiO2in Si+-Implanted Al2O3

Abstract
We measured Raman spectra of Si+-implanted Al2O3at room temperature before and after annealing in vacuum. It is found that SiO2is formed even before annealing and the Raman band attributed to the network Si-O-Si symmetric-stretching vibration mode grows with annealing between 300°C and 500°C. It is also found that Al atoms are emitted from the surface of Al2O3with annealing above 900°C. In forming SiO2in the surface layer of Al2O3, implanted Si atoms obtain oxygen atoms from Al2O3by breaking Al-O-Al bonds. We discuss the chemical reactions of implanted Si atoms with Al2O3induced by ion implantation and subsequent thermal annealing.