隨著半導體產業的進步，PCB板上的電子元件越做越小、元件堆疊密度越密集，一般的光學檢測面臨無法檢測的難題；另一方面，為了確保出貨產品的品質，目前廠商提出對整張PCB板進行線上檢測的要求。本研究根據X射線層析攝影合成原理的X射線系統，發展一套完整的缺陷檢測流程，對PCB板上每層電子元件進行線上檢測。
本研究的檢測流程包含系統誤差校正、背景補償、缺陷檢測等三個步驟。誤差校正步驟利用影像處理的方式，解決系統誤差破壞投影影像之間對應關係的問題，改善切層影像的品質；背景補償可以算是對檢測用的投影影像進行前處理的步驟，其目的是降低切層影像所受到的嚴重殘影效應，使後續缺陷檢測方法能夠更強健；在切層影像有殘影效應的考量下，整合切層影像、穿透式X射線影像的資訊與相對比較的理念，針對貫穿孔錫少、球柵陣列錫橋、球柵陣列空洞等缺陷，發展缺陷檢測演算法。最後，透過實驗結果可以確實看出本研究方法的有效性與強健性，並且應用在實際的機台上。

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