Patent ID: 6498081
Filing Date: 2002-12-24
Classification: H01L

Abstract:
A method of manufacturing a self-aligned contact hole in a semiconductor device, the method comprising:forming a plurality of gate patterns on a semiconductor substrate having an interposing gate insulating layer; forming a first insulating pattern which fills a gap between adjacent pairs of gate patterns while leaving a top surface of the gate patterns exposed; selectively etching a portion of the first insulating pattern by self-aligned contact etching to form a first contact hole exposing the semiconductor substrate; forming a spacer on a sidewall of the first contact hole; filling the first contact hole with a conductive silicon layer to form a first plug, wherein the first plug is filled to a height equal to the height of the spacer; performing a partial etchback to selectively etch the first plug and the gate pattern to a predetermined thickness, wherein after the partial etchback, a first horizontal plane defining a top surface of the first plug and the gate pattern is stepped down from a second horizontal plane defined by the height of the spacer, whereby a top portion of the spacer is projected higher than the surface of the first plug and the gate pattern; forming a second plug layer comprised of a conductive silicon layer on the first plug and the gate pattern, the second plug layer filling at least a gap between the projected spacers, and in which a thickness of the second plug layer at a portion filling the gap between the projected spacers is greater than a thickness of the second plug layer at a portion deposited on the gate pattern; etching back the second plug layer to a uniform thickness along the entire surface to a point where the second plug layer is equal to the height of the projected spacers, thereby filling the gap between the projected spacers to form a second plug connected to the first plug; forming a capping protective pattern covering the gate pattern while exposing a top surface of the second plug, the capping protective pattern extending between the first insulating pattern and the spacer; and forming a second insulating pattern on the capping protective pattern, the second insulating pattern having a second contact hole exposing at least the top surface of the second plug.