Semiconductor device and method for fabricating the same

Abstract

An inventive method for fabricating a semiconductor device includes the steps of: a) forming trenches in an actual element region and a dummy pattern region of a substrate by using a mask; b) depositing an insulator over the substrate, thereby forming an insulating film that fills at least the trenches; and c) removing a portion of the insulating film protruded from the trenches, thereby forming, in the trenches within the actual element region, a first embedded insulating film for isolation, and forming a second embedded insulating film in the trenches within the dummy pattern region. The dummy pattern region has dummy patterns in which no trenches are formed, and the widthwise size of each dummy pattern is four times or less of the depth of a portion of each trench provided in the substrate.

Dependencies are inferred from the claim text.