| 학회 |
한국재료학회 |
| 학술대회 |
2006년 가을 (11/03 ~ 11/03, 수원대학교) |
| 권호 |
12권 2호 |
| 발표분야 |
반도체 재료 |
| 제목 |
Effect of Alkaline Agent in Colloidal-Silica Slurry on Polysilicon Chemical-Mechanical Polishing Process. |
| 초록 |
Chemical Mechanical Polishing process is widely used to planarize the film surface in wafer during a floating gate manufacturing process of NAND flash memory, in which the design rule is below 65 nm to high processing speed and stable storage performance. Recently colloidal-silica slurry with addition of alkaline agent and organic amines have become used in Poly-Si CMP. Because they have high Poly-Si -to- oxide removal selectivity and improved Poly-Si surface uniformity, however its mechanism has not been clear. Therefore, we carried out a systematical experiment with different concentration of alkaline agent (NaOH, KOH, TMAH) in colloidal-silica slurry. Colloidal-silica slurry was prepared the abrasive size of around 30 nm with different concentration of up to 9.3 wt%. We also added an alkaline agent with amount of up to 1 wt% in slurry suspension. We additional added organic amines of up to 0.06 wt% to accelerate the removal rate of Poly-Si film. The Poly-Si film was deposited on the oxidized substrate in an LPCVD system at 530 oC. The films were polished with a Strasbaugh 6EC. The films thickness variation of the Poly-Si and oxide film of before and after CMP was measured with Nano-spec 180 (Nanometrics) and Ellipsometer (Ellipso tech.). Cross-sectional viewing was measured by SEM (Hitachi). We found that the Poly-Si removal rate decreased after slightly increase throughout the experimental range of alkaline agent concentration while a maintaining a low removal rate of below 50Å. But, the removal rate was almost independent Poly-Si of alkaline agent concentration. In addition, TMAH solution with colloidal silica abrasive and organic amines shows a good surface roughness of Poly-Si film after CMP. |
| 저자 |
Keum-Seok PARK1, Myoung-Yoon LEE1, Hyung-Soon PARK2, Ungyu PAIK3, Jea-Gun PARK1
|
| 소속 |
1Nano SOI process Lab. Hanyang Univ., 2Hynix Semiconductor Inc., 3Department of Ceramic Engineering |
| 키워드 |
Poly-Si CMP; alkaline agent; colloidal-silica slurry; uniformity
|
| E-Mail |
|
