RTCVD Model Reduction: A Collocation on Empirical Eigenfunctions Approach

A model of a three-zone Rapid Thermal Chemical Vapor Deposition (RTCVD) system is developed to study the e ects of spatial wafer temperature patterns and gas-phase reactant depletion on polysilicon deposition uniformity. A sequence of simulated runs is performed, varying the lamp power pro les so that di erent temperature modes are excited. The dominant spatial wafer thermal modes are extracted via proper orthogonal decomposition. A collocation formulation of Galerkin's method is used to discretize the original modeling equations giving a low-order model which looses little of the original's delity. We make use of the excellent predictive capabilities of the reduced model in a real-time RTP system simulator.

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