晶圓製造廠細部排程規劃模組之規劃

Abstract

半導體製造業的製造系統是現今產業中耗費設備成本最大,製程步驟數最 多與機器設備最複雜的.因此導致系統資源的高機器利用率,所以晶圓廠根 據瓶頸資源的產能負荷需求,規劃其主生產排程.然而產品的生產流動時間 卻受到短期產能限制資源漂移(CCR wandering)的影響.因為根據多位學者 的研究,產能限制資源會隨著時間而產生漂移,而產能限制資源的漂移將造 成生產規劃重排程的困擾.因此本論文細部排程規劃模組著重於完成主生 產排程規劃的目標.而主要的工作是預測產能限制資源漂移的時點與資源 的種類.細部排程規劃採用前推排程的做法.並以限制資源排程與非限制資 源產能規劃同時配合的方式,進行產能限制資源的排程規劃.且利用 Little's Law設定各迴圈(layer)之控制棒(rod),使動態產能需求規劃( DCRP)可利用迴圈控制棒,獲得每天各資源之預期產能負荷,並由此預測產 能負荷來判斷產能限制資源的漂移.最後由模擬驗證的結果可以看出,本論 文之細部排程規劃模組不但完成主生產排程的預期目標,達成預見產能限 制資源的漂移,同時也提昇製造系統的績效. The characteristics of wafer fabrication system include the high machine cost,the large number of manufacturing steps, and the high machine complexity. Theseresults in high machine utilization rates. The wafer fabrication factory thusplans its master production schedule (MPS) according to the capacity of bottle-neck machines. However, the flow times of products are affected by the short-term wandering of capacity constraint resources (CCRs). According to some researches, CCR wandering occurs frequently. It causes the need of rescheduling of production planning. This thesis emphasizes on the success planning of detailed schedule to accomplish the goal of MPS planning. Forecasting the tim-ing and the machine type that the CCR wanders to are the main jobs. The detail-ed schedule planning model adopts the concepts of forward scheduling. It plansthe schedule of CCRs while considering the capacity plan of every Non-CCR. Ituses the Little's Law to set the rod value between two consecutive layers. Then, the dynamic capacity requirement planning (DCRP) uses the rod of each layer to make the load profile for each Non-CCR. Base on these load profiles, the DCRP can determine whether the CCR wanders or not. The simulation results show the effects of applying the detailed schedule planning model. Since the CCR wandering is successive forecasted, the MPS planning results are achieved and the system performance is improved.