화학공학소재연구정보센터
홈 로그인 로그아웃 연락처 사이트맵
Clean Technology, Vol.23, No.4, 357-363, December, 2017
DOI10.7464/ksct.2017.23.4.357  Export Citation
포토레지스트 공정에서 높은 선택성을 가지는 초임계 이산화탄소/n-butyl acetate 공용매 시스템 연구
Study of Supercritical Carbon Dioxide/n-Butyl Acetate Co-solvent System with High Selectivity in Photoresist Removal Process
김동우, 허훈, 임권택†
  • 부경대학교 융합디스플레이공학과, 부산광역시 남구 대연 3동 부경대학교 대연캠퍼스 가온관 902호
Dong Woo Kim, Hoon Heo, and Kwon Teak Lim†
  • Department of Display & Engineering, Pukyong National University, Daeyeon 3-dong, Nam-gu, Busan, Korea
E-mail:
초록
본 연구에서는 초임계 이산화탄소/n-butyl acetate (scCO2/n-BA) 공용매를 사용하여 네거티브형 포토레지스트(PR)를 제거하는 실험을 진행하였다. scCO2와 n-BA의 용해도 평가를 통해 n-BA가 scCO2와 균일하게 섞이는 조건을 실험적으로 측정하였다. 다양한 실험 변수를 조정하여 포토레지스트 제거 실험을 진행하였고, 미노광 포토레지스트 제거에 대한 최적의 조건을 확립하였다. 또한, 노광된 PR과 미노광 PR의 제거율을 비교하여 scCO2/n-BA 공용매의 선택적 제거 성능을 확인하였다. 노광된 PR은 scCO2/n-BA 공용매 환경에서 매우 안정적으로 존재함을 관찰하였고, 미노광 PR은 160 bar, 40 ℃, 75 wt%n-BA 이상의 농도에서 완전히 제거됨을 확인하였다. scCO2/n-BA 공용매 시스템은 노광 PR과 미노광 PR 사이의 높은 선택성을 제공할 수 있으며, 네거티브 PR의 리소그래피 공정에서 높은 신뢰성을 부여할 것으로 기대된다.
In this study, the supercritical carbon dioxide (scCO2)/ n-butyl acetate (n-BA) co-solvent system was employed to remove an unexposed negative photoresist (PR) from the surface of a silicon wafer. In addition, the selectivity of the scCO2/n-BA co-solvent system was confirmed for the unexposed and exposed negative PR. Optimum conditions for removal of the unexposed PR were obtained from various conditions such as pressure, temperature and n-BA ratio. The n-BA was highly soluble in scCO2 without cloud point and phase separation in mostly experimental conditions. However, the scCO2/n-BA co-solvent was phase separated at 100 bar, above 80 ℃. The unexposed and exposed PR was swelled in scCO2 solvent at all experimental conditions. The complete removal of unexposed PR was achieved from the reaction condition of 160 bar, 10 min, 40 ℃ and 75 wt% n-BA in scCO2, as measured by ellipsometry. The exposed photoresist showed high stability in the scCO2/n-BA co-solvent system, which indicated that the scCO2/n-BA co-solvent system has high selectivity for the PR removal in photo lithograph process. The scCO2/n-BA co-solvent system not only prevent swelling of exposed PR, but also provide efficient and powful performance to removal unexposed PR.
Keywords:Supercritical carbon dioxide;Co-solvent;Negative photoresist;n-butyl acetate
  1. O'Shea KE, Kirmse KM, Fox MA, Johnston KP, J. Phys. Chem., 95, 7863 (1991)
  2. Campbell ML, Apodaca DL, Yates MZ, McCleskey TM, Birnbaum ER, Langmuir, 17(18), 5458 (2001)
  3. Carbonell RG, DeSimone JM, Novick BJ, U. S. Patent 6,083,565 (2000).
  4. Cooper AI, Wood CD, Holmes AB, Ind. Eng. Chem. Res., 39(12), 4741 (2000)
  5. Hwang HS, Yuvaraj H, Kim WK, Lee WK, Gal YS, Lim KT, J. Polym. Sci. A: Polym. Chem., 46, 1365 (2007)
  6. Ganapathy HS, Park SY, Lee WK, Park JM, Lim KT, J. Supercrit. Fluids, 51(2), 264 (2009)
  7. Shah PS, Holmes JD, Doty RC, Johnston KP, Korgel BA, J. Am. Chem. Soc., 122(17), 4245 (2000)
  8. Shah PS, Husain S, Johnston KP, Korgel BA, J. Phys. Chem. B, 105(39), 9433 (2001)
  9. Motiei M, Hacohen YR, Calderon-Moreno J, Gedanken A, J. Am. Chem. Soc., 123(35), 8624 (2001)
  10. Sun YP, Atorngitjawat P, Meziani MJ, Langmuir, 17(19), 5707 (2001)
  11. DeSimone JM, Romack TJ, Betts DE, Mcclain JB, U. S. Patent 5,866,005 (1999).
  12. Khanpour R, Sheikhi-Kouhsar MR, Esmaeilzadeh F, Mowla D, J. Supercrit. Fluids, 88, 1 (2014)
  13. Jones CA, Zweber A, Deyoung JP, McClain JB, Carbonell R, DeSimone JM, Crit. Rev. Solid State Mat. Sci., 29, 97 (2004)
  14. Weibel GL, Ober CK, Microelectronic Eng., 65, 145 (2003)
  15. Kim DH, Lim ES, Lim KT, Clean Technol., 17(4), 300 (2011)
  16. Lee MY, Do KM, Ganapathy HS, Lo YS, Kim JJ, Choi SJ, Lim KT, J. Supercrit. Fluids, 42(1), 150 (2007)
  17. Hwang HS, Bae JH, Jung JM, Lim KT, Microelectronic Eng., 87, 1696 (2010)
  18. Heyns M, Mertens P, Ruzyllo J, Leeman M, Solid State Technol., 42, 37 (1999)
  19. Abe H, Iwamoto H, Toshima T, Iino T, Gale GW, IEEE Trans. Semicond. Manuf., 16, 401 (2003)
  20. Clark PG, Christenson KK, Adv. Semicond. Manuf. Conf., (2005).
  21. Metselaar JW, Kuznetsov VI, Zhidkov AG, J. Appl. Phys., 75, 4910 (1994)
  22. Choi K, Ghosh S, Lim J, Lee CM, Appl. Surf. Sci., 206(1-4), 355 (2003)
  23. Maex K, Baklanov MR, Shamiryan D, Iacopi F, Brongersma SH, Yanovitskaya ZS, J. Appl. Phys., 93, 8793 (2003)
  24. Felix NM, Tsuchiya K, Ober CK, Adv. Mater., 18(4), 442 (2006)
  25. Pham VQ, Ferris RJ, Hamad A, Ober CK, Chem. Mater., 15, 4893 (2003)
  26. Hwang HS, Zakhidov AA, Lee JK, Andre X, DeFranco JA, Fong HH. Holmes AB, Malliaras GG, Ober CK, J. Mater. Chem., 18, 3087 (2008)
  27. Kirby CF, McHugh MA, Chem. Rev., 99(2), 565 (1999)
  28. Ghaziaskar HS, Nikravesh M, Fluid Phase Equilib., 206(1-2), 215 (2003)