TDD與IDD應用研究—以半導體產業為例

Abstract

考量到企業的持續經營與持續改善的原則，我們可以瞭解到企業在進行績效評估時莫不小心謹慎。但實際上，我們發現企業內部各部門所使用之評估指標往往會為了達到局部的效益而侵害到企業整體的利益，造成管理者在進行績效評估時產生困擾。因此本人藉由「目標」一書作者Dr. Goldratt提出之制約理論，希望以該理論所強調的以整體績效為重而發展出來的次系統績效評估方式—有效產出天•元（Throughput- Dollar-day, TDD）與存貨天•元（Inventory-Dollar-Day, IDD）來探討是否能夠解決目前半導體產業在績效評估時所使用之主要績效衡量指標（Key Performance Index, KPI）在評估時可能發生的問題，而試圖以制約理論（TOC）所提出之次系統績效評估方式來加以改善並且進一步以此評估方式為企業管理者提供一套簡單而正確的管理方法。 研究的結果顯示，目前半導體產業所使用的KPI確實會造成管理者在評估績效時落入過度重視局部績效的陷阱。而使用TOC所提出的次系統績效評估方式—TDD與IDD不僅能夠避免因為重視局部績效而產生問題更能夠為管理者在進行績效評估時提供快速而且明確的改善方向。

To consider the principle of continuously improvement and management, we know that focus on global performance is the key. But in fact, we find the departments of business are so emphasize on local benefits that hurt the global performance and create so many problems to managers. This is because the current KPI is not link the local performance to global performance. Two performance measurement indices TDD and IDD proposed by Dr. Goldratt claim that they can link local performance to global performance. In order to verify this advocation, this research first collects a series of KPI currently used by most semiconductor fab. Secondly, each KPI is reviewed and studied to see it whether can link local performance to global performance or not. Finally, a study of whether TDD/IDD can replace it is performance. Results of the study show that the KPI which currently used by the industries of semiconductor will fall into the trap that critically emphasize the local performance. Use TDD and IDD not only avoid the problems which produce by emphasize the local performance but also provide the managers a speedy and clearly direction of improvement.