| 摘要 |
PROBLEM TO BE SOLVED: To inhibit the occurrence of a divot on an STI end and reduce overhang of an embedded insulation film on a substrate thereby to inhibit residual of a gate insulation material.SOLUTION: A semiconductor device manufacturing method comprises: forming a first stopper film and a second stopper film on a substrate in this order in such a manner as to sandwich an intermediate film having an etching rate different from that of each of the first stopper film and the second stopper film; forming a first opening in the second stopper film by using a mask layer having a predetermined opening; enlarging the first opening in a horizontal direction of the substrate; forming a second opening in the first stopper film by using the mask layer; enlarging the second opening in the horizontal direction of the substrate; forming trenches in the substrate by using the mask layer, the first opening and the second opening; forming, after removing the mask layer, an embedded insulation film on the second stopper film and in the trenches; and polishing the embedded insulation film. |
