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Model Identification for Control System Design of a Commercial 12-inch Rapid Thermal Processor  

Yun, Woohyun (Department of Chemical and Biomolecular Engineering, Sogang University)
Ji, Sang Hyun (KORNIC Systems Co., Ltd.)
Na, Byung-Cheol (KORNIC Systems Co., Ltd.)
Won, Wangyun (Department of Chemical and Biomolecular Engineering, Sogang University)
Lee, Kwang Soon (Department of Chemical and Biomolecular Engineering, Sogang University)
Publication Information
Korean Chemical Engineering Research / v.46, no.3, 2008 , pp. 486-491 More about this Journal
Abstract
This paper describes a model identification method that has been applied to a commercial 12-inch RTP (rapid thermal processing) equipment with an ultimate aim to develop a high-performance advanced controller. Seven thermocouples are attached on the wafer surface and twelve tungsten-halogen lamp groups are used to heat up the wafer. To obtain a MIMO balanced state space model, multiple SIMO (single-input multiple-output) identification with highorder ARX models have been conducted and the resulting models have been combined, transformed and reduced to a MIMO balanced state space model through a balanced truncation technique. The identification experiments were designed to minimize the wafer warpage and an output linearization block has been proposed for compensation of the nonlinearity from the radiation-dominant heat transfer. As a result from the identification at around 600, 700, and $800^{\circ}C$, respectively, it was found that $y=T(K)^2$ and the state dimension of 80-100 are most desirable. With this choice the root-mean-square value of the one-step-ahead temperature prediction error was found to be in the range of 0.125-0.135 K.
Keywords
Identification; High-Order ARX Model; Balanced Realization; Balanced Truncation; Rapid Thermal Processing;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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