臺灣博碩士論文加值系統

摘要
EWMA回饋控制器是批次控制(run-by-run control, 簡稱 RbR control)之一重要控制方法，它是利用製程前一批量產出的結果，採用適當加權處理後來對下一批量的投入變數作調整，以求製程產出的最佳化。在現實環境中，製程會有老化的現象發生，在考慮製程老化對產出的影響下，則可採用double EWMA回饋控制器來調整生產製程。
傳統的double EWMA回饋控制器通常是採用固定折扣因子，然而，它卻很難同時兼顧製程初始偏差與製程產出之變異，因此使用較小折扣因子雖可確保製程的收斂性質，但往往需要一段較長的生產批量才能使製程產出達到目標值。此現象對現今IC產業『多樣少量』的生產型態將會造成極高的重作(rework)成本。針對 ‘固定折扣因子’的缺失，本研究以變動折扣因子的觀念來調整製程，在要求有限批量之總均方差(total mean square error, TMSE)最小化的目標下，建構出最適變動折扣因子控制器，並比較此最佳變動折扣因子控制器與傳統固定折扣因子控制器在執行效能上的優劣。

Abstract
EWMA feedback controller is one of the run-by-run control methods which is very important. This method uses the result of the previous batch to optimize the output of the process. By adopting appropriate weight factors, the input variables of the next batch size will be adjusted. In the real world, the manufacture process will age. Taking the effect of aging process to the output into consideration, we can use double feedback controller to adjust the production process.
In traditional, fixed discount factor is usually applied in double feedback controller. However, it often leads to a dilemma of the deviation in the initial production process or the variance of the output of the process. It is useful to insure the convergence of the manufacture process by adopting smaller discount factors, but it will need longer production period to make the output achieve the goal. This will lead high rework cost in the environment of IC production in nowadays. In order to redeem the inefficiencies of fixed discount factor, this research aims at the concept of the dynamic discount factor to adjust the production process. Under the objective of minimize the TMSE of the limitation batch size, this model formulated the optimal dynamic discount factor controller, and made comparison between this new method and the traditional one in the effectiveness of execution.

目錄
第一章 簡介 1
1.1 前言 1
1.2 研究動機 2
1.3 研究架構 3
第二章EWMA回饋控制器之文獻回顧 4
第三章 Double EWMA Controller變動折扣因子之選擇 10
3.1 Double EWMA Controller變動折扣因子之製程產出分析 11
3.2 製程干擾項為獨立常態分配下最適折扣因子之選取 14
3.3 績效表現 17
第四章 結論與後續研究 21
附錄 23
參考文獻 34

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