建構考慮新產品投片分配之半導體需求滿足模式

Construct a Demand Fulfillment Model Considering NTO Allocation for Semiconductor Manufacturing

吳健誠(Chien-Cheng Wu)

指導教授 ： 簡禎富

國立清華大學/工學院/工業工程與工程管理學系/碩士(2009年)

摘要

半導體產業由於設備成本高昂，因此產能的充分利用是半導體晶圓廠相當重要的議題；另一方面，在客戶導向的經營策略下，滿足客戶的需求亦是晶圓代工廠的主要目標之一。客戶需求的滿足對於產能利用率以及客戶滿意度均有相當重要的影響，因此，本研究探討如何規劃產品的分配與產能的調度以達到最佳的需求滿足及維持產能利用率。
由於半導體製程相當精密，產品需經過光罩製作、試產及驗證的流程後方能進行量產，需花費較長的前置時間及光罩成本，¬而且光罩無法在不同廠間互用。此些特性造成產品無法隨意分配至不同廠進行生產，故新產品的分配對未來各廠之需求影響極大。
本研究考慮新產品投片分配之影響以建構半導體業之需求滿足模式，並以成本最小化為目標，從產品分配決策對各廠生產產品能力之影響以及廠間與廠內之產能備援機制之採用來達成需求的滿足。本研究建構需求滿足之確定性模式及兩階段隨機規劃模式以在考慮需求不確定性的情況下進行決策。此外，本研究以一數值案例驗證隨機規劃模式在需求不確定之情況下之表現，其結果顯示隨機規劃模式在需求情境改變下較確定性模式表現更佳，能達到較低之成本來滿足顧客之需求。另外，本研究亦對不同需求水準下所進行之產品分配以及產能備援決策之差異進行討論。

關鍵字

製造策略 ； 新產品投片分配 ； 產能備援 ； 產能模式 ； 產能規劃 ； 半導體製造 ； 隨機規劃

並列摘要

In the semiconductor industry, the capital expenditure of capacity investment is so high that the manufacturers tend to keep their fabs highly utilized. In addition, customer satisfaction has been recognized as an important performance measure especially for foundry companies. Demand fulfillment has a great influence on both capacity utilization and customer satisfaction and therefore has become a critical job.
The semiconductor manufacturing process is very complex that each product is required to go through the process of mask creation, pilot run, and qualification so that it could be volume produced. This process will take a long lead time and high mask costs. Furthermore, the masks are not interchangeable between fabs. The above characteristics limit the production capability of fabs and products could not be arbitrarily assigned to fabs for production. Therefore, the NTO allocation affects the future demand of fabs very much.
This research aims to develop a demand fulfillment model considering NTO allocation problem. The decisions of product allocation and capacity backup are considered to construct the model. The problem is formulated as both deterministic model and stochastic model to incorporate demand uncertainty for decision making. Finally, a numerical study is conducted to evaluate the performance of the stochastic model and results show that the stochastic model can achieve a lower cost as the demand scenario changes. Also, discussions about the differences of decisions under different level of demand volume are provided.

並列關鍵字

Manufacturing Strategy ； NTO Allocation ； Capacity Backup ； Capacity Model ； Capacity Planning ； Semiconductor Manufacturing ； Stochastic Programming

參考文獻

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