Method of manufacturing semiconductor device
AssigneeRenesas Electronics Corporation
InventorTatsuya Usami
Life of this patent
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Abstract
A method of manufacturing a semiconductor device, including (a) forming an interlayer insulating film over a semiconductor substrate; (b) forming a third hard mask film over the interlayer insulating film; (c) forming a second hard mask film over the third hard mask film; (d) forming a first hard mask film over the second hard mask film; (e) after the step (d), forming a first opening in the first hard mask film and a second opening in the second hard mask film by etching the first and second hard mask films, respectively; (f) after the step (e), etching the first hard mask film so as to expand the first opening; and (g) after the step (f), etching the third hard mask film and a part of the interlayer insulating film in the second opening by using the second hard mask film as a mask.
Claims7
A method of manufacturing a semiconductor device, comprising:
- (a) forming an interlayer insulating film over a semiconductor substrate;
- (b) forming a third hard mask film over the interlayer insulating film;
- (c) forming a second hard mask film over the third hard mask film;
- (d) forming a first hard mask film over the second hard mask film;
- (e) after the step (d), forming a first opening in the first hard mask film and a second opening in the second hard mask film by etching the first and second hard mask films, respectively;
- (f) after the step (e), etching the first hard mask film so as to expand the first opening;
- (g) after the step (f), etching the third hard mask film and a part of the interlayer insulating film in the second opening by using the second hard mask film as a mask;
- (h) after the step (g), etching the second hard mask film in the first opening in order to expand the second opening by using the first hard mask film as a mask;
- (i) after the step (h), etching the third hard mask film and the interlayer insulating film by using the first and second hard mask films as a mask, thereby a trench and a via hole are formed in the interlayer insulating film;
- and
- (j) embedding a conductive film in the trench and the via hole,
- wherein the interlayer insulating film has a dielectric constant less than a dielectric constant of a silicon oxide, and
- wherein each of the first, second and third hard mask films is formed of a different material from the interlayer insulating film.
Dependencies are inferred from the claim text.