預警準則決策之分析-以某製造資訊系統為例

Abstract

在半導體產業中，為了充分利用產能之生產，單張工單可能會在多個晶圓廠進行生產。當工單實際傳送到其他晶圓廠時，其工單的資訊必須從儲存在原先製造執行系統(MES)傳送到其他廠區的製造執行系統。這種的資訊傳送可能會失敗；因此建立一個預警機制提高預警和緊急恢復程序，以提高資訊傳送的可靠性。預警機制在特定的時間間隔(Tc)下，定期評估跨廠資訊傳送系統，並基於警報門檻(Th)的設定，以作為發警報之依據。（Tc,Th）組合的設定對檢修成本和資訊傳送品質有顯著的影響。本研究欲在既定資訊傳送品質之要求下，找出能達到最小化的總檢修成本之最適（Tc,Th）組合。所以研究中發展出一個模型，來評估每個（Tc,Th）的傳送品質和檢修成本，並使用全面搜尋的方法，找出最佳選擇，數值實驗也正能說明本研究所設定的方法。最後期許本研究能有效協助工程師作為該設定預警準則決策之依據。

In semiconductor industry, a job may be manufactured across multiple production plants (fabs) in order to leverage manufacturing capacity. While a job is physically transferred to the other fab, its information stored in the original manufacturing execution system (MES) must be transferred to the MES of the other fab. Such an information transfer may fail; therefore an early warning mechanism is established to improve the reliability of data information transfers through preventive and emergency recovery procedures. The early warning mechanism periodically evaluates the inter-plant information transfer system at a particular time interval (Tc) and determines whether to issue an alarm based on a predetermined alarm threshold (Th). The setting of (Tc, Th) has a significant impact on the maintenance cost and the quality of information transfers. This research attempts to find an optimal setting of (Tc, Th) in order to minimize the maintenance cost subject that the quality of information transfers meets a given target. We develop a model for evaluating the quality and maintenance cost for each (Tc, Th) alternative, and use an exhaustive search method to find an optimal alternative. Numerical experiments are carried out to illustrate the proposed method. This research effectively helps engineers in the decisions on determining alarm criteria.