SOI WAFER AND MANUFACTURE THEREOF

摘要

PROBLEM TO BE SOLVED: To provide an SOI wafer with improved film thickness uniformity of an SOI layer. SOLUTION: Out of a bonded wafer to form an SOI layer on and a base wafer as a supporting substrate, at least the bonded wafer is formed with an oxide film. Then, hydrogen ions or noble gas ions are implanted into the bond wafer through the oxide film to form a fine babble layer (sealed layer) in the bond wafer. After that, the bond wafer is airtightly adhered at the ion implanted face to the base wafer. Then, the combined wafer is heat-treated and the bonded wafer is separated into a thin film with the fine babble layer as a cleaved face to manufacture an SOI wafer. The thickness of the oxide film formed on the bonded wafer is so set that the variation in thickness of the oxide film formed on the bonded wafer may be smaller than the variation in ion implantation depth.