Patent ID: 7592263

Claim:
A method of manufacturing a semiconductor device, by use of a perforating process including providing a mask having an opening on a semiconductor substrate, and forming plural types of through-holes different in width dimension in said semiconductor substrate, wherein a removal rate of a semiconductor material in the depth direction of said semiconductor substrate becomes higher as said opening has a wider opening width, said method comprising: a first step of forming a concave portion in a first surface of a semiconductor substrate, in a first region of said semiconductor substrate corresponding to the opening of said mask having a relatively narrow opening width, to allow said first region to have a thickness dimension less than that of a second, remaining, region of said semiconductor substrate; and a second step of performing said perforating process using said mask provided on a second, opposite, surface of said semiconductor substrate, to form a first through-hole reaching said first surface in said second region of said semiconductor substrate and a second through-hole reaching said concave portion.