本研究利用有限元素分析軟體 ANSYS，深入探討了TO系列封裝在溫度循環測試中，因熱膨脹係數不一致所引致的顯著熱應力。這種不均勻的熱應力會導致焊點邊緣及幾何轉角處出現應力集中，最終可能造成錫裂失效，對需承受高功率負載的電子元件可靠度構成嚴重威脅。為提升高功率半導體功率元件的可靠性，我們對其熱應力進行了分析並提出了結構優化設計。主要探討的關鍵因子包括跳線形式、跳線厚度、錫膏材料類型以及錫膏印刷厚度。研究中，本文採用有限元素分析法進行穩態熱應力模擬，並結合田口品質工程法的L8直交表與訊號雜訊比分析，找出最佳控制因子組合，有效解決因材料特性差異所產生的殘餘應力問題。透過對跳線幾何外型與錫膏材料參數的優化，我們成功將焊點最大等效應力從276.48 MPa顯著降低至136.78 MPa，此最佳化設計提升了高功率構裝元件在嚴苛環境下的品質。

This paper employs the finite element analysis software ANSYS to investigate the significant thermal stress in TO-series semiconductor packages induced by coefficient of thermal expansion (CTE) mismatch during temperature cycling tests (TCT). The uneven thermal stress leads to stress concentration at solder joint edges and geometric corners, which can ultimately result in solder cracking (Solder Cracking) failure and pose a serious threat to the reliability of high-power electronic components. This study focuses on thermal stress analysis and structural design optimization of high-power semiconductor packages, primarily investigating four key control factors: clip geometry type, clip thickness, solder paste material type, and solder paste printing thickness. Finite element analysis was employed to simulate steady-state thermal stress, and the Taguchi quality engineering method combined with an L8 orthogonal array and signal-to-noise ratio (S/N ratio) analysis was used to identify the optimal control factor combination. Through optimization of the clip geometry and solder paste material parameters, the maximum equivalent stress at the solder joint was significantly reduced from 276.48 MPa to 136.78 MPa, achieving a 50.5% reduction. This optimized design markedly enhances the quality and service life of high-power packaged components operating under harsh thermal cycling environments.

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