Crystalline disorder reduction and defect-type change in silicon on sapphire films by silicon implantation and subsequent thermal annealing

Abstract

Ion channeling techniques have been utilized to study the improvement of crystalline quality of SOS films by Si implantation and subsequent thermal annealing. Crystalline disorder was greatly reduced when an amorphous layer was formed at the Si/sapphire interface and annealed at temperatures higher than 600 °C. It was shown that the regrowth of the amorphous layer proceeded from the surface toward the inner region. In the 200–400‐keV proton channeling measurements, the dechanneled fraction was found to be proportional to the square root of the proton energy in the crystalline improved SOS, whereas as‐grown SOS had no energy dependence. This indicates a defect‐type change from microtwins to dislocations during the above treatment.