Patent ID: 7816162

Claim:
A semiconductor device manufacturing method comprising: a first semiconductor layer forming step forming on a semiconductor substrate a first semiconductor layer that has an etching rate; a second semiconductor layer forming step forming on the first semiconductor layer a second semiconductor layer that has an etching rate slower than the etching rate of the first semiconductor layer; a third semiconductor layer forming step forming on the second semiconductor layer a third semiconductor layer that has an etching rate faster than the etching rate of the second semiconductor layer; an etching mask forming step forming an etching mask on the third semiconductor layer; an etching step etching, by using the etching mask and an etchant, the third semiconductor layer, the second semiconductor layer and the first semiconductor layer in a region outside the etching mask; and a thin film forming step forming a thin film such that the thin film continuously coats an upper surface and side surfaces of a semiconductor layer group that includes the third semiconductor layer, the second semiconductor layer and the first semiconductor layer remaining after the etching step.