晶圓檢測在監控晶圓產品品質中扮演重要的角色。然而，為獲取實際量測值則需要購置大量量測機台與耗費因執行實際量測所須之生產週期時間來達成。因此，在不犧牲產品品質的原則下，能盡可能地降低抽樣頻率以減少生產成本，為高度優先之目標。文獻顯示已有數種抽樣方法被提出，以便能達到此目的。這些方法乃是於生產製程中利用檢視實際抽樣樣本之方式，來監測產品品質。然而，在製程穩定的條件下，即使實際資料並未獲得，我們亦可採用虛擬量測(VM)來監視產品品質。因此，運用可靠的虛擬量測系統來設計取樣決策機制，將可能更進一步地降低抽測頻率。
作者過去已發展完成全自動虛擬量測(AVM)系統於多種虛擬量測應用。因此，本論文將採兩階段的方式，以研發並實現建置一個通用型抽樣決策機制。其中，第一階段將應用AVM系統內之各式指標，來發展抽測頻率固定之智慧型取樣決策機制，以便在維持虛擬量測精度的條件下，能更進一步地降低量測抽樣頻率。而第二階段則更進一步地研發具自動調配抽測頻率之動態智慧型取樣決策(Dynamic ISD)機制，使本智慧型取樣決策機制能更具彈性，且更有效率。

Wafer inspection plays a significant role in monitoring the quality of wafers production for continuous improvement. However, it requires measuring tools and additional cycle time to do real metrology, which is costly and time-consuming. Therefore, reducing sampling rate to as low as possible is a high priority to reduce production cost. Several sampling methods in the literature were proposed to achieve this goal. They utilized real sampling inspections as the representatives for the other related wafers to monitor the whole production process. Under the condition of stable manufacturing process, virtual metrology (VM) may be applied to monitor the quality of wafers, while real metrology is unavailable. Therefore, the sampling rate may further be reduced with a sampling decision scheme being designed according to reliable VM.
Two stages of tasks are designed and implemented to construct a generic intelligent sampling decision scheme. The first stage is to develop the Static Intelligent Sampling Decision (Static ISD) scheme with static sampling rate and the advanced second stage is to build the Dynamic Intelligent Sampling Decision (Dynamic ISD) scheme with dynamic/automated sampling rate. The authors have developed the automatic virtual metrology (AVM) system for various VM applications. Therefore, this paper focuses on applying various indices of the AVM system to develop both the Static and Dynamic ISD schemes for reducing sampling rate, while VM accuracy is still sustained.

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http://dx.doi.org/10.1080/00207543.2014.955924