| AVS 54th International Symposium | |
| Thin Film | Thursday Sessions |
| Session TF-ThP |
| Session: | Aspects of Thin Films Poster Session |
| Presenter: | S.-W. Park, Chosun University, Korea |
| Authors: | S.-W. Park, Chosun University, Korea W.-S. Lee, Chosun University, Korea Y.-J. Seo, Daebul University, Korea G.-W. Choi, Chosun University, Korea S.-J. Han, Chosun University, Korea Y.-K. Lee, Chosun University, Korea |
| Correspondent: | Click to Email |
One of the critical consumables in chemical mechanical polishing (CMP) is a specialized solution or slurry, which typically contains both abrasives and chemicals acting together to planarize films. The slurry designed for optimal performance should produce reasonable polish rates, acceptable polish rate selectivity with respect to the underlying layer, low surface defects after polishing, and good slurry stability. In single abrasive slurry (SAS), the solid phase consists of only one type of abrasive particle. On the other hand, mixed abrasive slurry (MAS) consists of a mixture of at least two types of abrasive particles, which can be chosen from inorganic (alumina, silica, ceria, zirconia, titania, manganese oxide, etc) or organic (polymeric resins) groups. In this work, in order to prepare the MAS, KOH-based fumed silica slurry of pH 11 with solid content of 13 % was diluted in de-ionized water (DIW) with 1:10 ratio. The manganese oxide (MnO2) abrasives particles were then added in the diluted silica slurry. The concentration of manganese oxide abrasive was varied from 1 wt% to 5 wt%. The surface quality after polishing is important issue in TEOS-oxide CMP. A surface with a very low scratch level is obtained by chemically modifying the abrasive surface. The particle size distribution of MAS as a function of mixed amount of manganese oxide abrasive particles was also observed a bimodal particle size distribution with the two peaks at mean aggregate particle sizes of 250 nm and 2250 nm. Formation of nanometer and large size particles is perhaps, the result of aggregation of modified manganese oxide particles. This is due to an interplay between the abrasive action of larger manganese oxide particles and chemical-tooth nature of the smaller silica particles surrounding the larger manganese oxide particles. The slurry composition is further optimized to allow an excellent polishing performance yielding good surface quality while maintaining high removal rate. In addition, it is anticipated that there were be few special slurry handling problems in a fabrication production environment because relatively benign chemistry is used. This work was supported by grant No. (R01-2006-000-11275-0) from the Basic Research Program of the Korea Science & Engineering Foundation and by Korea Research Foundation Grant (KRF-2006-005-J00902).