Patent ID: 7998870

Claim:
A method for forming a semiconductor device comprising: providing a substrate having a plurality of landing plugs contacting the substrate and an etch stop layer provided over the landing plugs, and a first insulating layer over the etch stop layer; etching the first insulating layer and the etch stop layer to form a contact pad hole exposing at least one of the landing plugs; forming a contact pad in the contact pad hole, the contact pad contacting the exposed landing plug; etching the first insulating layer to form a bit line contact hole that is wider laterally than the contact pad and exposes a portion of the etch stop layer provided adjacent to the contact pad; forming a spacer at sidewalls of the bit line contact hole; and providing a conductive layer within the bit line contact hole and over the first insulating layer to form a bit line, wherein the bit line has substantially the same width in an active region of the substrate and in a device isolation region of the substrate.