由於高效率及快速的轉換性，絕緣閘雙極性電晶體(IGBT)模組成為了在電動車及油電混合車的主要元件。在模組中，連結模組中各個元件的方式為粗打線科技。在現今的打線科技中，因為擁有較高的電流容載率及價格便宜的優勢，銅線已經漸漸被指定為主要的打線材料。然而很少文獻提及楔形銅打線在鋁金屬化薄膜上之接點的電遷移導致破壞機制。在本篇研究當中，我們探討了銅-鋁楔型打線系統在環境溫度175℃下的大電流破壞機制。電流密度範圍從4x104 到1X105 A/cm2。此篇研究也分析了試片電阻變化對於銅線和鋁金屬墊的微結構改變影響。實驗結果顯示出在電流密度4x104 到1X105 A/cm2範圍中，無論在何種電流方向狀況下，異常的裂縫總形成在第二接點上且明顯伴隨著介金屬化合物成長。我們推論此異常的裂縫形成原因是第二接點的接點面積較第一接點的接點面積小，導致第二接點承受較高的焦耳熱，加速了介金屬化合物生長。越多的介金屬化合物生成造成更多的裂縫在接點中。此外發現電流擁擠效應可能會發生在接點的後跟處，並且進一步使用電流密度模擬來探討。我們也藉由計算相對應的化學位能差及電遷移所導致擴散流量來解釋破壞機制。當電流密度上升至1x10⁵ A/cm²，銅線會因為大量的焦耳熱生成在0.5小時內融化。

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