METHOD OF PRODUCING BONDED WAFER

PURPOSE: A method for manufacturing a bonded wafer is provided to improve surface roughness and obtain high thickness uniformity. CONSTITUTION: An oxygen ion is implanted to a wafer for an active layer to form an oxygen ion implantation layer. The oxygen ion implanted surface of the wafer for an active layer is directly bonded by the wafer for a support layer or bonded by an insulation layer. A thermal process is performed to increase the bond intensity of the bonded wafer. A part of the wafer for the active layer is thinned in the bonded wafer to expose the oxygen ion implantation layer. The oxygen ion implantation layer is removed from the wafer for the active layer in the bonded wafer.