現今針對高度競爭的電子產業，製程中的線上檢測不僅可以提高產品的良率、發現製程上的缺失，更能減少在不良品上加工的浪費。然而，傳統的二維自動光學檢測(Automatic Optical Inspection)設備，通常僅能檢測物件表面的缺陷，而在製程上所產生的內部瑕疵或隱藏於元件後的缺陷，利用具有穿透能力的X射線便可為此問題提供一個可能的解決方案。此時，利用X射線電腦斷層掃瞄法（X-Ray Computer Tomography）來進行各物件三維結構的影像重建，最後藉由所得到之立體影像來判斷生產線上的製程缺陷。在本研究中，使用同步代數重建法(Simultaneous Algebraic Reconstruction Technique，SART)針對BGA錫球進行檢測，同時探討影響SART的參數，校正出適合之參數重建三維空間的BGA錫球結構，並由所得到的影像來分析BGA是否含有內部瑕疵或缺陷。

On-line optical inspection is become popular, because it can not only improve the product quality but also identify the failure of the process immediately. And hence, not only the production yield can be improved, but also the waste due to failure can be reduced.
However, traditional optical inspection machine is limited to detect defects appeared on the surface of the product. In order to detect defects beneath surface, X-Ray image is a powerful tool to apply. Computed tomography can provide the size and shape at any desired section about the defect inside a product while traditional X-Ray image can only provide vague information about the defect.
In this dissertation, Simultaneous Algebraic Reconstruction Technique (SART) for computer tomography was adopted to inspect BGA defects. In our simulation study, the effects of various parameters on reconstructed images are also studied. As a result, it was found that the SART with proper parameters used is able to rebuild the 3-D BGA structure properly and the inside flaw can be detected.

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