限制理論應用於晶圓製造廠之生產規劃與控制

Abstract

在設備投資金額愈龐大的工廠中，愈多管理者落入成本會計的傳統迷思，以追求所有機台高利用率為生產績效目標，並以提高在製品水準做為提昇產出量的方法，付出的代價反而是生產週期時間增加，導致市場反應能力下降，至於實質產出，則不一定獲得相對的提昇。基於各個組織都有其限制所在，本研究認為只要能維持瓶頸機台高使用率及生產順暢，可使產出量最大化；而非瓶頸機台以配合瓶頸機台之生產需求為目標，可使在製品量與生產週期時間降低。根據限制管理之理念，構建一個以限制理論為基礎的生產規劃與控制模式，透過投料與派工方法，充份利用瓶頸資源，以達到產出量最大化、生產週期時間縮短及訂單達交率提高之研究目的。經由晶圓製造廠之應用驗証顯示，以限制理論所發展之投料與派工模式，不僅使瓶頸資源充份利用，同時在生產週期時間、產出量、在製品量及交期達成率都有良好的績效表現。

In factories with enormous amount facilities investment, more managers face the perplexity from traditional cost accounting. Achieving higher utilization for all machines is one of the production key performance indices, so managers are asked to increase WIP level to enlarge output. Actually the higher WIP level cannot guarantee for more output. But we must suffer from longer cycle time and lower flexibility of manufacture, even quality. Therefore, the actual output do not get the relative increase. Based on every factory has its own capacity constraint resource, this paper thinks that to keep highest utilization and production smooth of the bottleneck machines will maximize output. The production goal of non-bottleneck machines is to meet the demand of bottleneck machines, and it can reduce WIP level and cycle time. This paper applies TOC concept in developing an order releasing and dispatching rule model to reach three purposes: maximize output, reduce cycle time and increase on time delivery. From the results by implementing in a Fab, it indicates that the developed model does have good performance in the three purposes of this research.