Stability Analysis of EWMA Run-to-Run Controller Subjects to Stochastic Metrology Delay
نویسندگان
چکیده
In the semiconductor manufacturing batch processes, each step is a complicated physicochemical batch process; generally it is difficult to perform measurements on-line. The effect of the metrology delay on the stability of the system is an important issue needs to be understood. This paper investigates the stability of systems under exponentially weighted moving average (EWMA) runto-run control with stochastic metrology delay. Necessary and sufficient conditions for the stochastic stability are established. Some numerical examples are provided to illustrate how to get the stability regions based on the proposed theorem.
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