Patent ID: 9214380
Filing Date: 2015-12-15
Classification: H01L

Abstract:
1. A method for preparing a bonded semiconductor-on-sapphire (SOS) substrate comprising a semiconductor film on a surface of a sapphire substrate, comprising the steps of: providing the sapphire substrate and a semiconductor substrate which is a single crystal silicon substrate or a silicon substrate on which an oxide film has been grown; implanting hydrogen atom ions (H activating one or both of the surface of the sapphire substrate and the surface of the semiconductor substrate into which the hydrogen atom ions or hydrogen molecule ions have been implanted; bonding the surface of the semiconductor substrate and the surface of the sapphire substrate at a temperature of from 50° C. to 350° C.; heating the bonded substrates to a temperature in a range of from 200° C. to 350° C. to form a bonded body; and irradiating visible light from a sapphire substrate side to the ion-implanted layer of the semiconductor substrate for making an interface of the ion-implanted layer brittle, while keeping a temperature of the bonded body higher than the temperature at which the surfaces of the semiconductor substrate and the sapphire substrate were bonded, so as to transfer the semiconductor film from the semiconductor substrate to the sapphire substrate, wherein the temperature of the bonded body during irradiation of the visible light is from 30° C. to 100° C. higher than the temperature at which the surfaces of the semiconductor substrate and the sapphire substrate were bonded, wherein the visible light is a laser beam having a wavelength in a range of from 400 to 700 nm and irradiation energy per area 5 J/cm