In this paper we present an enhanced algorithm to integrate the functions of statistical process control and run-by-run feedback control. In the statistical process control function, the Shewhart control chart is used to detect a large process deviation while the EWMA control chart is used to detect a small process deviation. In the run-by-run feedback control function, a moving average formulation is used to update the control model and generate the recipe on a run by run basis. To validate the effectiveness of the proposed algorithm, Monte Carlo simulations are performed to simulate processes that are subject to shifts and drift. Results of the simulations show that the enhanced algorithm is better than the current schemes such as a combined EWMA control chart and EWMA feedback control scheme.
英文關鍵字
Statistical Process Control, Run-by-run Feedback Control, EWMA
