| US 7,501,051 B2 | ||
| Electropolishing electrolyte and method for planarizing a metal layer using the same | ||
| Jia Min Shieh, Hsinchu (Taiwan); Sue Hong Liu, Pingtung (Taiwan); and Bau Tong Dai, Baushan Township, Hsinchu County (Taiwan) | ||
| Assigned to BASF Aktiengesellschaft, Ludwigshafen (Germany) | ||
| Filed on Feb. 04, 2005, as Appl. No. 11/51,163. | ||
| Claims priority of application No. 93130211 A (TW), filed on Oct. 06, 2004. | ||
| Prior Publication US 2006/0070888 A1, Apr. 06, 2006 | ||
| Int. Cl. B23H 11/00 (2006.01) | ||
| U.S. Cl. 205—677 [205/668; 205/669; 205/674; 205/675; 205/676; 205/678; 205/680; 438/691; 438/692; 438/697; 438/700] | 14 Claims |
| 1. An electropolishing electrolyte comprising an acid solution and an alcohol additive, wherein the contact angle of the alcohol additive on a metal layer under electropolishing is smaller than the contact angle of the acid solution, wherein the acid solution comprises phosphoric acid and an organic acid selected from the group consisting of acetic acid and citric acid; the alcohol additive is selected from the group consisting of methanol, ethanol and glycerol; and the volumetric ratio of the alcohol additive to the acid solution is between 1:50 and 1:200. |