US Patent 7288791 Epitaxial wafer and method for manufacturing method

It is an object of the present invention to provide an epitaxial wafer with fewer pit defects in the epitaxial layer of a silicon monocrystalline wafer that has been doped with arsenic. Pit defects tend to occur when gas etching is performed prior to epitaxial film formation, but this tendency is reversed and a sound epitaxial layer is obtained by setting the crystal plane orientation to (100) and specifying the range of the tilt angle for the angle θ in the [001] direction or [001] direction or the angle φ in the [010] direction or [010] direction with respect to the [100] axis.