Patent ID: 8357586

Claim:
A method for manufacturing an SOI wafer, comprising at least the steps of: bonding a silicon wafer with or without an oxide film onto a handle wafer to prepare a bonded substrate, wherein the silicon wafer has an ion implanted layer formed by implanting hydrogen ions and/or rare gas ions into the silicon wafer; peeling the silicon wafer along the ion implanted layer, thereby transferring the silicon wafer onto the handle wafer to produce a post-peeling SOI wafer; immersing the post-peeling SOI wafer in an aqueous ammonia-hydrogen peroxide solution; and performing a heat treatment at a temperature of 900° C. or higher on the immersed post-peeling SOI wafer, and/or polishing a silicon film layer of the immersed post-peeling SOI wafer, through CMP polishing by 10 to 50 nm, wherein the aqueous ammonia-hydrogen peroxide solution contains, based on a volume composition ratio, at least: 0.05 to 2 of 29 wt % ammonia water; 0.01 to 0.5 of 30 wt % hydrogen peroxide water; and 10 of water.