저압 플라즈마 세정가스에 따른 세정특성 연구

구희준; 고광진; 정찬교

Clean Technology, Vol.7, No.3, 203-214, September, 2001

Export Citation

저압 플라즈마 세정가스에 따른 세정특성 연구

A Study on the Cleaning Characteristics according to the process gas of Low-Pressure Plasma

구희준, 고광진, 정찬교

초록

플라즈마를 발생시키는 반응기체의 종류에 따라 실리콘 산화막 세정에 어떠한 영향을 미치는지에 대해 연구하였다. 압력 (100 mTorr), 전력 (300 W, 500 W), 전극간 거리 (5, 8, 11.5 cm), 세정시간 (90초, 180초), 가스유량 (50 sccm) 등의 변수들을 고정시키고 CHF3, CF4, 아르곤, 산소 등의 세정가스를 변화시키며 세정성능을 비교하였다. 세정결과 아르곤 플라즈마는 단지 물리적인 스퍼터링 효과만으로 세정속도가 느렸다. 산소 플라즈마는 5 cm 전극거리, 300 W, 180초 세정시 좋은 세정효과를 내었으나, 표면거칠기가 증가하였다. CF4 플라즈마의 경우 가장 좋은 세정효과를 얻었다. CHF3 플라즈마는 CFx/F의 비율을 낮출 수 있는 첨가기체가 필요함을 알 수 있었다. CHF3에 아르곤을 첨가하였을 경우에는 원활한 세정효과를 얻을 수 없었으나, 산소를 첨가하였을 경우 좋은 세정효과를 얻을 수 있었다.

A silicon oxide cleaning characteristic and its mechanism were studied in RF plasma cleaning system with various gases such as CHF3, CF4, Argon, oxygen and mixing gas. The experimental parameters - working pressure (100 mTorr), RF power (300 W, 500 W), electrode distance (5 cm, 8 cm, 11.5 cm), cleaning time (90, 180 seconds), gas flow (50 sccm) were fixed to compare cleaning efficiency by gas types. The results were as follows. First, the argon plasma is retaining only physical sputtering effect and etch rate was low. Second, the oxygen plasma showed good cleaning efficiency in electrode distace of 5 cm, 300 W, 180 secs, but surface roughness increased. Third, CF4 Plasma could get the best cleaning efficiency. Fourth, CHF3 plasma could know that addition gas that can lower the CFx/F ratio need. We could not get good cleaning efficiency in case of added argon to CHF3. But, we could get good cleaning efficiency in case added oxygen.

[References]

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Delfino M, Salimian S, Hodul D, J. Appl. Phys., 70, 1712 (1991)
Kern W, Handbook of Semiconductor Wafer Cleaning Technology, Noyes Pub. (1993)
Ruzyllo J, Evanluating the Feasibility of Dry Cleaning of Silicon Wafers, Microcontamination, 6, 39 (1988)
McNab TK, Cluster Tools, Part 1: Emerging Processes, Semiconductor International, Aug., 58 (1990)
Mathad GS, Hess DW, Meyyappan M, Plasma Processing for Silicon-Based Integrated Circuits, The Electrochemical Society Interface (1999)
Chapman B, Glow Discharge Processes, John Wiley & Sons (1980)
Watanabe S, Jpn. J. Appl. Phys., 31 (1992)
d'Agostion R, Plasma Deposition, Treatment and Etching of Polymers, Academic Press (1990)
Sakuma K, Machida K, Kamoshida K, Sato Y, Imai K, Arai E, J. Vac. Sci. Technol. B, 13(3), 902 (1995)
Jackson R, Pidduck AJ, Green MA, Removal of Surface Contamination after Reactive Ion Etching of Silicon Dioxide, Vacuum, 45, 519 (1994)
Hwang KH, Yoon E, Whang KW, Lee JY, Appl. Phys. Lett., 67, 3590 (1995)
d'Agostion R, Plasma-Surface Interactions, Plasma Processing of Semiconductors pp. 221-242 (1997)
Lieberman MA, Lichtenberg AJ, Principles of Plasma Discharges and Materials Processing, John Wiley & Sons (1994)
이호준, 자화유도결합 플라즈마의 건식 식각 특성에 관한 연구, 서울대학교 박사학위논문 (1996)
도현호, 전자회전공명 플라즈마 식각장치에서의 산화막 식각특성 및 식각구조에 관한 연구, 서울대학교 박사학위논문 (1997)

[1] Sumi H, Yanagida T, Sugano Y, Sasserath JN, New Contact Process Using Soft Etch for Stable Ohmic Characteristics and Its Applications to 0.1 Micron CMOS Devices, International Electron Device Meeting, San Francisco, Dec. 11-14, 113 (1994)

[2] Delfino M, Salimian S, Hodul D, J. Appl. Phys., 70, 1712 (1991)

[3] Kern W, Handbook of Semiconductor Wafer Cleaning Technology, Noyes Pub. (1993)

[4] Ruzyllo J, Evanluating the Feasibility of Dry Cleaning of Silicon Wafers, Microcontamination, 6, 39 (1988)

[5] McNab TK, Cluster Tools, Part 1: Emerging Processes, Semiconductor International, Aug., 58 (1990)

[6] Mathad GS, Hess DW, Meyyappan M, Plasma Processing for Silicon-Based Integrated Circuits, The Electrochemical Society Interface (1999)

[7] Chapman B, Glow Discharge Processes, John Wiley & Sons (1980)

[8] Watanabe S, Jpn. J. Appl. Phys., 31 (1992)

[9] d'Agostion R, Plasma Deposition, Treatment and Etching of Polymers, Academic Press (1990)

[10] Sakuma K, Machida K, Kamoshida K, Sato Y, Imai K, Arai E, J. Vac. Sci. Technol. B, 13(3), 902 (1995)

[11] Jackson R, Pidduck AJ, Green MA, Removal of Surface Contamination after Reactive Ion Etching of Silicon Dioxide, Vacuum, 45, 519 (1994)

[12] Hwang KH, Yoon E, Whang KW, Lee JY, Appl. Phys. Lett., 67, 3590 (1995)

[13] d'Agostion R, Plasma-Surface Interactions, Plasma Processing of Semiconductors pp. 221-242 (1997)

[14] Lieberman MA, Lichtenberg AJ, Principles of Plasma Discharges and Materials Processing, John Wiley & Sons (1994)

[15] 이호준, 자화유도결합 플라즈마의 건식 식각 특성에 관한 연구, 서울대학교 박사학위논문 (1996)

[16] 도현호, 전자회전공명 플라즈마 식각장치에서의 산화막 식각특성 및 식각구조에 관한 연구, 서울대학교 박사학위논문 (1997)