Patent ID: 8236667
Filing Date: 2012-08-07
Classification: H01L

Abstract:
1. A manufacturing method for manufacturing a silicon on insulator (SOI) wafer by bonding a single crystal silicon wafer to a transparent insulation substrate comprising a silica substrate and a sapphire (alumina) substrate, and thereafter making the single crystal silicon wafer to be thinned to form an SOI layer on the transparent insulation substrate, the manufacturing method performing at least: forming an ion injection layer within the single crystal silicon wafer, by injecting at least one of a hydrogen ion and a rare gas ion from a surface of the single crystal silicon wafer wherein an ion injection dose used in the forming of the ion injection layer is greater than 8×10 processing the ion injection surface of the single crystal silicon wafer and/or a surface of the transparent insulation substrate using plasma and/or ozone; bonding the ion injection surface of the single crystal silicon wafer to a surface of the transparent insulation substrate, by bringing them to close contact with each other in a room temperature, with the processed surface(s) as bonding surface(s); obtaining an SOI wafer, by mechanically peeling the single crystal silicon wafer by giving an impact to the ion injection layer, to form an SOI layer on the transparent insulation substrate; performing thermal processing for flattening a surface of the SOI layer, to the resulting SOI wafer, under an atmosphere of an inert gas, a hydrogen gas, or a mixture gas of the inert gas and the hydrogen gas; raising a bonding strength by performing thermal processing to the bonded wafer under a temperature of 100-300 degrees centigrade, after the bonding of the ion injection surface and before the obtaining of an SOI wafer; and after the performance of thermal processing for flattening a surface of the SOI layer: forming a thermal oxide layer on the surface of the SOI layer by performing thermal oxidation to the SOI wafer to which the thermal processing has been performed; and reducing a thickness of the SOI layer by removing the thermal oxide layer using touch polishing.