Method for producing a bonded SOI wafer

摘要

A silicon wafer is produced by growing a silicon single crystal ingot having a resistivity of 100 Ω•cm or more and an initial interstitial oxygen concentration of 10 to 25 ppma by the Czochralski method, processing the silicon single crystal ingot into a wafer, and subjecting the wafer to an oxygen precipitation heat treatment so that a residual interstitial oxygen concentration in the wafer should become 8 ppma or less. A silicon wafer produced as described above shows little decrease in resistivity even after a heat treatment in device production etc. Further, if a silicon wafer is produced and heat-treated so that the wafer should have the above-defined initial interstitial oxygen concentration and residual interstitial oxygen concentration, slip dislocations in a subsequent heat treatment process are prevented irrespective of resistivity. Furthermore, by forming an epitaxial layer on a surface of a silicon wafer of the present invention, a high resistivity epitaxial wafer can be produced, which is free from slip dislocations etc. and can be used for various devices. The application concerns a method for producing a bonded SOI wafer using such a silicon wafer.