Patent ID: 8759229

Claim:
A method for manufacturing an epitaxial wafer comprising: smoothing a surface of a single thin discoid wafer obtained by slicing a silicon single crystal ingot; and forming an epitaxial layer formed of a silicon single crystal on the smoothed surface of the wafer based on epitaxial growth, wherein said smoothing comprises: detecting irregularities on an unsmoothed and unetched front surface of the wafer with a detector; storing the detected irregularities in memory of a controller; controlling a position and a discharge time of a nozzle for supplying an acid etchant in accordance with the stored irregularities on the unsmoothed and unetched front surface of the wafer by said controller; rotating the wafer in a horizontal direction; supplying the acid etchant from the nozzle to the unsmoothed and unetched front surface of the rotating wafer to spread the supplied etchant on the entire front surface of the wafer by a centrifugal force; rinsing and drying the front surface of the wafer; subsequently turning over the wafer with the dried front surface; and processing an unsmoothed and unetched rear surface of the wafer in a same manner as said detecting, said storing, said controlling, said rotating, said supplying, and said rinsing and drying, thereby smoothing the front surface and rear surface of the wafer.