Patent ID: 6787457
Filing Date: 2004-09-07
Classification: H01L

Abstract:
A method of fabricating a semiconductor device, in which an anti-reflection film is etched with a resist taken as a mask, comprising:forming a device isolation oxide on a wafer substrate; forming a polysilicon film on both the wafer substrate and the isolation oxide; forming an insulation film on the polysilicon film; forming an anti-reflection film on said insulating film; forming a resist on said anti-reflection film and forming an initial opening portion in said resist; removing a portion, positioned at said initial opening portion of said anti-reflection film by etching, using an etching gas containing a substituted hydrocarbon with a halogen, such that an interfacing surface of the insulating layer is exposed, thus forming a deepened opening portion, the deepened opening portion comprising the initial opening portion; forming a side wall blocking film on side walls of said deepened opening portion to suppress extension of said deepened opening portion, the side wall blocking film having a thickness; removing a portion, positioned at said deepened opening portion, of the insulating film by etching, thus forming a further deepened opening portion, wherein a width of the deepened opening portion is greater than a width of the further deepened opening portion by an amount equal to twice the thickness of the side wall blocking film, and wherein the wafer substrate is not etched during the aforementioned steps.