Method for producing bonded SOI wafer
AssigneeShin-Etsu Handotai Co., Ltd.
InventorsToru Ishizuka, Masatake Nakano
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Abstract
A method for producing a bonded SOI wafer by bonding a bond wafer and a base wafer, each being formed of a silicon single crystal, together with a silicon oxide film placed therebetween, the method including: preparing, as the base wafer, a silicon single crystal wafer whose resistivity is 100 Ω·cm or more and initial interstitial oxygen concentration is 10 ppma or less; forming, on the front surface of the base wafer, a silicon oxide film by performing, on the base wafer, heat treatment in an oxidizing atmosphere at a temperature of 700° C. or higher and 1000° C. or lower for 5 hours or more; bonding the base wafer and the bond wafer together with the silicon oxide film placed therebetween; and thinning the bonded bond wafer to form an SOI layer.
Claims6
A method for producing a bonded SOI wafer by bonding a bond wafer and a base wafer, each being formed of a silicon single crystal, together with a silicon oxide film placed therebetween, comprising:
- preparing, as the base wafer, a silicon single crystal wafer whose resistivity is 100 Ω·cm or more, initial interstitial oxygen concentration is 10 ppma or less, and nitrogen concentration is 1×1013 to 1×1015 atoms/cm3;
- forming, on a front surface of the base wafer, a silicon oxide film for a BOX film whose thickness is 1 μm or more by performing, on the base wafer, heat treatment in an oxidizing atmosphere at a temperature of 700° C. or higher and 1000° C. or lower for 5 hours or more, the heat treatment doubling as annihilation of NO donors associated with nitrogen doping;
- bonding the base wafer and the bond wafer together with the silicon oxide film placed therebetween;
- and
- thinning the bonded bond wafer to form an SOI layer.
Dependencies are inferred from the claim text.