| US 7,547,635 B2 | ||
| Process for etching dielectric films with improved resist and/or etch profile characteristics | ||
| Aaron Eppler, Fremont, Calif. (US); Mukund Srinivasan, Fremont, Calif. (US); and Robert Chebi, Fremont, Calif. (US) | ||
| Assigned to Lam Research Corporation, Fremont, Calif. (US) | ||
| Filed on Jun. 14, 2002, as Appl. No. 10/170,424. | ||
| Prior Publication US 2003/0232504 A1, Dec. 18, 2003 | ||
| Int. Cl. H01L 21/302 (2006.01) | ||
| U.S. Cl. 438—710 [438/714; 438/715; 438/723; 438/725; 438/735; 438/743; 216/67; 216/79; 216/80; 252/79.1] | 22 Claims |
| 1. A method of etching openings in a dielectric layer, comprising:
supporting a semiconductor substrate on a substrate support in a plasma etch reactor, the substrate having a dielectric layer
and a patterned photoresist layer and/or hardmask above the dielectric layer;
supplying to the plasma etch reactor an etchant gas comprising (i) a fluorocarbon gas (CxFyHz, where x≧1, y≧1, and z≧0), (ii) silane-containing gas, (iii) an optional oxygen-containing gas, and (iv) an optional inert
gas; wherein the flow rate ratio of silane-containing gas to fluorocarbon gas is less than or equal to 0.1;
energizing the etchant gas into a plasma state, and
etching openings in the dielectric layer with increased photoresist and/or hardmask to dielectric layer selectivity and decreased
photoresist distortion or striation,
wherein the dielectric layer comprises an inorganic low-k material or an organic low-k material.
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