考慮擴充瓶頸機台與附屬工具之中期產能規劃問題

以TFT-LCD產業為例，本研究探討供應鏈多廠區產能規劃問題，由於面板產業之產品種類廣泛與複雜、生產種類多樣化、且為不同世代的廠區結構，造成產品需求量不斷改變以及短期規劃時程下產能不易擴充，因此必須妥善的進行產能規劃以滿足市場需求，產能配置與擴充的決策成為TFT-LCD製造業值得探討的議題。TFT-LCD面板產業製程分為陣列(Array)、組立(Cell)和模組(Module)製程，其中陣列與組立製程產能有限以及資源設備昂貴，所花費的投資成本高，在此生產環境下，必須相當重視如何有效的分配產能以使獲利最大，並規劃完善的產能投資決策以滿足市場需求。本研究僅探討單階層之陣列製造廠區，在此產能不易擴充的環境下之中期產能規劃問題，透過購買瓶頸機台及附屬工具–「光罩」的決策來增加各廠區間的生產彈性，並建構TFT-LCD產業之中期產能規劃數學模式，以最佳化分配產能及決定應於何時購買擴充產能的資源設備，並達到所追求之目標。最後透過實際案例的結果及敏感度分析可得知產能擴充並非大量生產邊際利潤高之產品族，擴充生產產能取決於各產品族的經濟切割率以及產能擴充能力的限制，此為影響產能擴充的重要因素。在進行產能規劃的同時，需求預測、總產能限制以及擴充成本為產能擴充之重要因子，並且影響了淨利潤的高低。

關鍵字

薄膜電晶體液晶顯示器；產能規劃；多廠區規劃；產能擴充；混合整數線性規劃

並列摘要

This study explores issues on medium-term multi-plant capacity allocation and expansion planning in the TFT-LCD industry. Since the Array stage is the bottleneck of this production network, our research objective is to simultaneously seek an optimal capacity allocation plan and capacity expansion policy under single-stage, multi-generation and multi-site structures. Capacity allocation decides on profitable product mixes and allocated production quantities of each product group at each production site. An increment strategy for the numbers of bottleneck machines and auxiliary tools—"photo mask" is proposed to increase the flexibility of production. The decisions include how to allocate appropriately the forecast demands of products among multiple sites and how to decide on the numbers of bottleneck machines and auxiliary tools. A mathematical programming model of capacity planning is formulated to solve this problem and find the best solution, which considers practical characteristics and constraints of TFT-LCD manufacturing. Finally, an industrial case study modified from a Taiwanese TFT-LCD manufacturer is illustrated and sensitivity analysis of some influential parameters is also addressed.