Method of manufacturing a semiconductor device using anti-reflective layer and self-aligned contact technique and semiconductor device manufactured thereby

Abstract

A method of manufacturing a semiconductor device includes sequential steps of forming a gate insulating layer, a first conductive layer, an etch stop layer, a hard mask layer, and an anti-reflective layer on a semiconductor substrate. The anti-reflective layer, hard mask layer, and etch stop layer are then partially etched according to a pattern to create an anti-reflective layer pattern, hard mask layer pattern, and etch stop layer pattern. The anti-reflective layer can be formed of a porous plasma silicon oxinitride layer to keep irregular reflections to a minimum. The anti-reflective layer pattern is then etched, followed by an etching of the first conductive layer to form a gate electrode under the etch stop layer pattern. A conformal spacer insulating layer is formed on the whole surface of the semiconductor substrate, and an interlayer insulating layer is formed on the spacer insulating layer so as to fill openings between the gate electrodes. The interlayer insulating layer, the spacer insulating layer and the hard mask pattern are etched using the etch stop layer pattern as an etch mask, and thereby forming self-aligned contact holes exposing the semiconductor substrate between the gate electrodes.