Articles & Issues
- Conflict of Interest
- In relation to this article, we declare that there is no conflict of interest.
-
This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/bync/3.0) which permits
unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Copyright © KIChE. All rights reserved.
All issues
Q-ILC를 이용한 고속 열처리 공정의 온도 제어
Temperature Control in Rapid Thermal Processing Using Q-lLC
HWAHAK KONGHAK, April 1999, 37(2), 304-312(9), NONE
Download PDF
Abstract
RTP는 짧은 가공시간으로 열적 결함을 줄일 수 있는 단일 웨이퍼 가공 공정으로 현재 반도체 산업에서 많이 적용되고 있다. 그러나 웨이퍼 표면의 온도 균일도 유지가 아직도 어려운 문제로 남아 있다. 본 연구에서는 모델 오차가 있는 경우에도 점진적으로 제어 오차를 최소화시킬 수 있는 Q-lLC(Quadratic criterion-based Iterative learning Control)를 이용한 열린 루프 제어방법을 제안하였으며,8 inch 웨이퍼용 RTP 모델을 대상으로 그 성능을 검증하였다. Q-ILC의 설계에 필요한 시변 선형 모델은 subspace 방법을 통해 구한 각 온도별 시불변 선형 모델의 조합으로 유도하였다. 또한 계산량을 줄일 수 있는 차수 감소 Q-ILC를 설계하고 그 성능을 Q-lLC와 비교하였다.
Although RTP(rapid thermal processing) has gained popularity recently in the semi-conductor industry due a difficult problem. In this study, as an open-loop control technique for RTP temperature distribution, we propose to use Q-ILC(quadratic criterion-based iterative learning control), which can asymptotically attains the minimum achievable control error even under a significant model error, and investigate the performance with an 8-inch silicon wafer RTP model. The time-varying linear model required in the design of Q-ILC was derived by combining the time-invariant linear models identified using the subspace method at each temperature zone. In addition, in order to reduce the heavy computational burden, a reduced-order Q-ILC algorithm was designed and its performance was compared with that of full-order algorithm.
References
Lord HA, IEEE Trans. Semicond. Manuf., 1(3), 105 (1988)
Gyuresik RS, Riley TJ, Sorrell FY, IEEE Trans. Semicond. Manuf., 4(1), 9 (1991)
Apte PP, Saraswat KC, IEEE Trans. Semicond. Manuf., 5(3), 180 (1992)
Stuber JD, Trachtenberg I, Edgar TF, Proc. of 33rd Conf. Decision and Control, 79 (1994)
Gyugyi PJ, Cho YM, Franklin G, Kailath T, Roy RH, The 1st IEEE Conf. on Control Application, 374 (1992)
Lee KS, Bang SH, Chang KS, J. Process Control, 4(2), 77 (1994)
Kim WC, Chin IS, Choi J, Lee KS, Comput. Chem. Eng., submitted (1997)
Norman SA, Ph.D. Thesis, Stanford University (1989)
Vanoverschee P, Demoor B, Automatica, 30(1), 75 (1994)
Kim SH, Moon HJ, Lee KS, J. Control. Automation Systems Eng., 4(4), 413 (1998)
Butler SW, J. Vac. Sci. Technol. B, 13(4), 1917 (1995)
Gyuresik RS, Riley TJ, Sorrell FY, IEEE Trans. Semicond. Manuf., 4(1), 9 (1991)
Apte PP, Saraswat KC, IEEE Trans. Semicond. Manuf., 5(3), 180 (1992)
Stuber JD, Trachtenberg I, Edgar TF, Proc. of 33rd Conf. Decision and Control, 79 (1994)
Gyugyi PJ, Cho YM, Franklin G, Kailath T, Roy RH, The 1st IEEE Conf. on Control Application, 374 (1992)
Lee KS, Bang SH, Chang KS, J. Process Control, 4(2), 77 (1994)
Kim WC, Chin IS, Choi J, Lee KS, Comput. Chem. Eng., submitted (1997)
Norman SA, Ph.D. Thesis, Stanford University (1989)
Vanoverschee P, Demoor B, Automatica, 30(1), 75 (1994)
Kim SH, Moon HJ, Lee KS, J. Control. Automation Systems Eng., 4(4), 413 (1998)
Butler SW, J. Vac. Sci. Technol. B, 13(4), 1917 (1995)
