Patent ID: 7927957
Filing Date: 2011-04-19
Classification: H01L

Abstract:
1. A method for producing a bonded silicon wafer comprising implanting oxygen ions from one-side face of a silicon wafer for active layer with a substrate oxygen concentration of 10×10 17 /cm 3 to 18×10 17 /cm 3 (old ASTM conversion) sliced so as to have such a wafer face that an inclination angle θ (compound angle) with respect to a face perpendicular to <100> orientation or <110> orientation of a silicon single crystal ingot is 0°<θ≦0.15° to form an oxygen ion implanted layer at a given depth position from the one-side face of the silicon wafer for active layer; bonding the one-side face of the silicon wafer for active layer to one-side face of a silicon wafer for support to form a silicon wafer composite; heat-treating (a first heat treatment step) the silicon wafer composite to strengthen the bonding and to convert the oxygen ion implanted layer into an inner SiO exposing the inner SiO removing the inner SiO planarizing and polishing a surface of the silicon wafer composite after the removal of the inner SiO