TFT-LCD（thin film transistor-liquid crystal display）面板由薄膜電晶體（TFT Array）、面板組立（Cell）及模組（Module）三大製程所構成，其中以TFT Array製程為最重要。由於TFT Array製程為三段製程之首，且因製程時間最長、機台設備最為昂貴，成為TFT-LCD製程的瓶頸所在。TFT Array製程的產出情形對整個生產鏈有重要的影響，若未能達到生產規劃部門所制定的產出計畫，將使後續製程發生缺料的狀況。因此，為能達成日產出計畫及提昇瓶頸產能的利用率，TFT Array需要一能同時考量此兩項目標的投料計畫。
TFT Array製程具有許多特性與限制，使其現場排程問題變得相當複雜。TFT Array製具有受限產能迴流的特性，再加上其中的瓶頸黃光製程需使用除機台之外的副資源—光罩，每種產品的各迴流層都有其專屬的光罩，且光罩與瓶頸機台之間有一特定的搭配限制。同時，因為光罩成本昂貴，光罩數量也成為在排程上需考量的限制。在迴流、光罩與機台搭配關係及光罩數量限制的特性下，造成TFT Array的現場排程問題變得相當複雜。針對此些特性及生產排程考量的目標，本研究提出一考量光罩限制的兩階段排程法。在第一階段優先處理光罩與瓶頸機台的配置問題，並作為第二階段瓶頸作業排程時的輸入資訊；第二階段則是以DBR排程方法精神為基的瓶頸作業排程，以求得適宜的投料計畫。
藉由實驗設計與模擬分析發現，本研究所提的兩階段排程方法能迅速解決現今TFT Array作排程時所面臨到的難題，且在延遲時間及瓶頸機台使用率的表現呈現良好的結果，可輔助TFT Array廠作投料規劃時使用。

A TFT-LCD (thin film transistor-liquid crystal display) manufacturing consists of three main processes: TFT Array, Cell and Module process, and TFT Array is the most important of all. Being the first manufacturing stage, the throughput of TFT Array has a significant impact on the subsequent processes. In order to prevent material shortages in Cell plants, TFT Array plants must produce the right products with correct quantities to comply with the daily throughput schedule. In addition, the resource utilization in TFT Array process has been placed high attention due to expensive equipments. As a result, an effective release plan is necessitated for TFT Array process to achieve the daily throughput schedule and simultaneously exploit the finite resource.
Many manufacturing characteristics and constraints in TFT Array process lead to a great complexity in TFT Array shop floor scheduling. Firstly, TFT Array process is a re-entrant flow, in which a similar sequence of processing step is repeated for five times. Further, the photolithography stage, the bottleneck in TFT Array process, requires a second resource in addition to machines (steppers or scanners). Photo masks and scanners are both indispensable while executing exposure operation in the photolithography stage. Every product with different re-entrant layer requires a unique mask and consequently each has a set of mask with five different pieces. Moreover, there is a tool eligibility issue between masks and scanners. Masks are approved to be used in specific scanners for quality considerations. Since TFT Array process is characterized as reentry and mask constraints, it is regarded as a complicated scheduling problem and is more difficult to solve than classical ones.
In this study, we decompose the complex problems and present a two-phase scheduling method to acquire a suitable release plan for TFT Array process, which are masks allocation and a DBR-based bottleneck operations scheduling. In the first phase, masks allocation problem is quickly solved by mathematical programming and each mask is designated to one or more scanners. Phase one is similar to a rough-cut capacity planning. Afterward the detail bottleneck operations scheduling and the release plan is established according to DBR (drum-buffer-rope) scheduling method in accordance with the mask allocation result from the previous phase.
Finally, relative scheduling performances of the two-phase scheduling method are provided by a simulation model extracting from a real TFT-LCD manufacturing company. The release plans developed for the tardiness and resource utilization criteria reveal that the proposed methodology quickly solves the difficult scheduling problem and performs well.

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