在IC供應鏈體系下，IC設計廠專注於其設計本業，而設計後續製造生產則委外由晶圓與封測廠負責。由於晶圓生產長達6~10週，時間變異大，對委外之需求端而言，除了有效率規劃下單排程外，能掌握供應商在製品資訊與供給時程，必要時能與供應商進行有依據的協調拉貨，實為需求端的重要任務。
本研究基於虛擬生產管制系統(Virtual Production Control System, VPCS)，以不同規劃模型對缺料部分提出下單建議或拉貨協調。在下單建議上，透過建立混合整數線性規劃(Mixed Integer Linear Programming, MIP)模型，以最大化達交率為目標，滿足下單前推時間限制與製程月產能限制條件下，求得最佳之採購建議。就拉貨協調而言，收集在製品資料與VPCS產出推估，推算在不同物料之產出時間，並建立多目標規劃(Multi Objective Programming, MOP)模型，以最小化拉貨數量和最小化供需差額為目標，可求解拉貨建議。
在研究成果上，透過整合VPCS與最佳化規劃模型。相較某IC設計廠下單建議而言，本研究之資料正確性可由原98%提升至100%，而整體達交率可從93.2%提升至96.2%。在拉貨協調上，若基於供應商產出時程，產品之個別達交率可由73% 提升至85%；而若基於VPCS產出推估，則達交率可進一步提升至91%。

An IC design company focuses its IC design and releases following manufacturing activities to foundries and packaging/testing companies in an IC supply chain. Due to long and variant time for wafer production, the important tasks of the outsourcing requestor of a IC design company are how to effectively schedule order plans and evidently coordinate with suppliers for pulling in or pushing out IC according to information and delivery plans of WIP.
This study based the virtual production control system (VPCS) suggests purchase orders by a programming model and proposes feasible pull-in plans by production estimation. For purchase order suggestion, a mixed integer programming model is used to find the optimal suggestion by maximizing the order-fill rate (OFR) under constraints, i.e. lead time, capacity, and inventory minimization. For pull-in coordination, a multi-objective programming model is presented to derive the feasible plan by minimizing the pull-in numbers and differences between demand and supply according to WIP information and production output times estimated by the VPCS.
Results of this work indicate that the data accuracy is improved from 98% to 100% and the overall OFR is improved from 93.2% to 96.2% while using the proposed method to compare with the IC design company. Moreover, the individual OFR of a product is improved from 73% to 85% while based on the projected schedule by the supplier; however, the OFR can be up to 91% when applying the estimation of the VPCS.

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