| 학회 | 한국재료학회 |
| 학술대회 | 2006년 가을 (11/03 ~ 11/03, 수원대학교) |
| 권호 | 12권 2호 |
| 발표분야 | 반도체 재료 |
| 제목 | Effects of Surfactant Molecular weight and Concentration in Nano-Ceria Slurry on Nanotopography Impact in Chemical Mechanical Polishing |
| 초록 | Chemical mechanical polishing (CMP) is widely used to planarize the wafer surface during the device manufacturing. Recently, the “nanotopography” of the silicon wafer has become an important issue in Shallow Trench Isolation (STI)-CMP process, since it seriously affects the post-CMP film thickness variation. We investigated the dependency of nanotopography impact on surfactant concentration and Molecular weight in ceria (CeO2) slurry as one of the key factors in STI-CMP process. The slurries were prepared with different organic surfactant concentration from 0 to 0.8 wt% with different molecular weight of 5K, 30K, and 90K. The plasma-enhanced tetra-ethyl-ortho-silicate (PETEOS) films were polished with a Strasbaugh 6EC. The nanotopography variation was measured by Nano-Mapper (ADE). The oxide film thickness variation of the wafer before and after CMP was measured with a reflector meter NanoSpec 8300 ( Nanometrics). The profiles of the oxide (SiO2) thickness deviation (OTD) after CMP coincided well with those of the nanotopography variation, which means the OTD after CMP was mainly caused by the nanotopography. We controlled the polishing time to keep a constant removal depth of 3000 Å through the slurries including various concentrations of the surfactant and molecular weight in ceria slurry. The standard deviation of OTD amplitude was calculated and we found the results as follows: 1) The OTD after CMP increased according to the increase of the surfactant concentration. 2) This trend (1) was more remarkable for higher molecular weight of surfactant in slurry suspension. The mechanisms on these result is discussed and attributed to the surfactant adsorption on the film surface. 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 | Hyuk-Yul CHOI1, Hyun-Goo KANG1, Jun-Seok KIM1, Ungyu PAIK2, Jea-Gun PARK3 |
| 소속 | 1Nano-SOI Process Lab. Hanyang Univ., 2Department of Ceramic Engineering, 3Hanynag Univ. |
| 키워드 | Nanotopography; STI-CMP; Ceria; Molecular Weight |
