METHOD FOR CALCULATING WARPING OF BONDED SOI WAFER AND METHOD FOR MANUFACTURING BONDED SOI WAFER

摘要

The present invention provides a method for calculating the warping of a bonded SOI wafer. An SOI epitaxial wafer having a structure composed of a BOX layer on a base wafer and an SOI layer on the BOX layer is manufactured by forming a thermal oxide film on either a bond wafer surface or a base wafer surface or both surfaces thereof and bonding said bond wafer and said base wafer via the thermal oxide film, and then thinning said bond wafer. The bonded SOI wafer is manufactured by growing the epitaxial layer. The method for calculating the warping for a bonded SOI wafer comprises calculating warping (A) generated when performing the epitaxial growth for an assumed silicon monocrystal wafer under the assumption that said SOI epitaxial wafer is the silicon monocrystal wafer having the same dopant concentration as that of said bond wafer, calculating warping (B) due to the thickness of the BOX layer of said SOI epitaxial wafer, setting as warping (C) the actual measured value of the warping of the base wafer prior to bonding, and calculating the total of the warping (A + B + C) as said warping of the bonded SOI wafer. Thus, a method for preliminarily calculating the warping of the bonded SOI wafer and a method for manufacturing a bonded SOI wafer having desired warping by using the calculation method are provided.