| 학회 | 한국재료학회 |
| 학술대회 | 2006년 봄 (05/19 ~ 05/20, 경상대학교 ) |
| 권호 | 12권 1호 |
| 발표분야 | 반도체재료 |
| 제목 | Reduction of Large Particles and Light Point Defects (LPD) by Aging and Selective Sedimentation Process in Ceria Slurry for Shallow Trench Isolation Chemical Mechanical Polishing |
| 초록 | In contemporary ULSI fabrication, chemical mechanical polishing (CMP) is an essential process, and shallow trench isolation (STI) process is one of the most important applications of CMP technology. Recently, it is the ceria slurry that enables the application of STI-CMP, in which the selectivity of removal rate between oxide (SiO2) and nitride (Si3N4) layers is a critical factor. Ceria slurry with an organic additives shows higher oxide-to-nitride selectivity than fumed silica based slurry. However, the ceria slurry has a major disadvantage which is defects on the film surface, which can be induced with only a small amount of large particles. In this study, therefore, we investigated the aging and sedimentation process of ceria slurry on slurry characteristics, such as the particle size distribution, the large particle count and the dispersion stability and remaining light point defects (LPD) on wafer surface during the STI-CMP. In addition, we confirmed that the aging time and temperature were considered as important variables which give more influences on slurry characteristics in STI-CMP. By using aging and sedimentation process, large particles produced by either hard agglomeration or soft flocculation in ceria slurry were reduced and the dispersion stability of ceria particles in the slurry could be also improved. In the CMP evaluation, as a result, defects on wafer surface were significantly restrained, while maintaining the reasonable oxide removal rate and oxide and nitride selectivity. The Korea Ministry of Science and Technology supported this work through the National Research Laboratory (NRL) program. We thank SUMCO Corp. and Hynix Semiconductor, Inc. for helping us with our experiments. |
| 저자 | Byong-Seog Lee1, Hyun-Goo Kang2, Kyung-Woong Park1, Ungyu Paik2, Jea-Gun Park1 |
| 소속 | 1Nano SOI Process Laboratory, 2Hanyang Univ. |
| 키워드 | aging; sedimentation process; large particles; ceria; STI-CMP; defect |
