| US 7,611,994 B2 | ||
| Fine patterning method for semiconductor device | ||
| Kazutaka Akiyama, Matsudo (Japan) | ||
| Assigned to Kabushiki Kaisha Toshiba, Tokyo (Japan) | ||
| Filed on Mar. 31, 2006, as Appl. No. 11/393,718. | ||
| Claims priority of application No. 2005-104874 (JP), filed on Mar. 31, 2005. | ||
| Prior Publication US 2006/0240639 A1, Oct. 26, 2006 | ||
| Int. Cl. H01L 21/302 (2006.01) | ||
| U.S. Cl. 438—717 [438/445; 438/736; 257/E21.023] | 20 Claims |
| 1. A method of manufacturing a semiconductor device, comprising:
forming an insulation film on a semiconductor substrate;
forming a stopper film on the insulation film, the stopper film having a large etching selectivity relative to the insulation
film and having a first film thickness;
forming a first mask material on the stopper film, the first mask material having a second film thickness that is less than
the first film thickness;
forming a first mask by patterning the first mask material using an inversion mask having a final dimension;
forming an opening portion wider than the first mask by etching the stopper film using the first mask, thereby performing
a process causing the stopper film to have a pattern thinner than the first mask;
filling the opening portion with a second mask material;
forming a second mask of the second mask material by removing the first mask and the stopper film, the second mask having
a thickness which is greater than the second film thickness; and
etching the insulation film deeper than the first film thickness using the second mask.
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