| US 7,510,976 B2 | ||
| Dielectric plasma etch process with in-situ amorphous carbon mask with improved critical dimension and etch selectivity | ||
| Shing-Li Sung, Campbell, Calif. (US); Wonseok Lee, Pleasanton, Calif. (US); Judy Wang, Cupertino, Calif. (US); and Shawming Ma, Sunnyvale, Calif. (US) | ||
| Assigned to Applied Materials, Inc., Santa Clara, Calif. (US) | ||
| Filed on May 16, 2006, as Appl. No. 11/434,951. | ||
| Claims priority of provisional application 60/793935, filed on Apr. 21, 2006. | ||
| Prior Publication US 2007/0249171 A1, Oct. 25, 2007 | ||
| Int. Cl. H01L 21/00 (2006.01); B44C 1/22 (2006.01) | ||
| U.S. Cl. 438—710 [438/706; 438/736; 216/41; 216/47; 216/67] | 20 Claims |
| 1. A plasma-enhanced process performed in a single plasma reactor chamber for etching a thin film layer on a workpiece, using
a hard mask layer comprising amorphous carbon layer (ACL) overlying the thin film layer and an anti-reflection coating (ARC)
overlying the ACL, comprising:
placing said workpiece in the plasma reactor chamber and etching a pattern in said ARC in accordance with a photoresist mask
overlying the ARC, using a plasma produced from a fluorine-containing process gas;
performing a first transition step by replacing said fluorine-containing process gas with an inert species process gas and
maintaining a plasma in said reactor chamber;
etching a pattern in said ACL using said ARC as an etch mask by replacing said inert species process gas with a process gas
containing hydrogen and maintaining a plasma in said chamber;
performing a flush step by replacing said hydrogen-containing process gas with inert species process gas and maintaining a
plasma in said chamber; and
etching a pattern in said thin film layer using said ACL as a hard mask by replacing said inert species process gas in said
chamber with a species capable of etching said thin film layer.
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