銲線接合製程因為技術成熟且產品可靠度高，目前仍是受歡迎的技術之ㄧ，以往製程以金線作為主要的銲線材料，但金價格持續上揚，成本考量之下，遂以銅線取代金線。
本文首先利用有限元素法模擬金及銅銲線接合之衝擊階段，分析兩者差異並作為之後多尺度模擬的比較基準。金銲線接合模擬部分，由於塊材鋁墊彈性模數高於金球，引發鋁墊及其下方金屬層的應力集中現象。而銅銲線接合模擬部分，雖然塊材鋁墊彈性模數低於銅球，但因為塊材鋁墊降伏強度不夠高，經由銅球衝壓後不僅產生鋁擠出現象，甚至在鋁墊及其下方金屬層內更存在嚴重的應力集中。
最後，本研究透過分子動力學模擬單晶鋁(100)之等速單軸拉伸來獲得單晶鋁(100)的材料性質，並結合有限元素法進行3D銲線接合之多尺度模擬分析，試圖以改變鋁墊材質的方式來減少銅球衝壓對基板造成的損壞。模擬結果顯示單晶鋁(100)具有比塊材鋁更低的彈性模數與更高的降伏強度，若利用單晶鋁(100)來取代塊材鋁作為接墊材料，不僅可以減低鋁墊與其下方金屬層的應力集中，達到防護基板的功效，更可以防止銅球衝壓對鋁墊造成的擠出現象。

Ball bonding with gold wire has been the preferred choice to connect semiconductor chip and a lead frame. Recently, copper wires have been increasingly used to replace gold wires because of the rising price of gold. However, copper is harder than gold and has the tendency to induce the damage of bond pad or other underlying layers. Herein, Al pad material has to be changed from bulk to single crystal with (100) surface orientation in order to improve bonding reliability.
Firstly, finite element method was adopted to simulate 3D wire bonding. Also, from the impact of gold wire bonding, the stress concentration was found on pad and underlying layers due to the higher elastic modulus of bulk Al. During copper ball impact, there is not only the serious stress concentration at pad, but also a pad splash due to the insufficient strength of bulk Al, even though bulk Al has a lower elastic modulus.
Secondly, material properties of Al(100) were obtained by uniaxial tensile tests at constant speed. With molecular dynamics method, the incorporated result showed that Al(100) has the lower elastic modulus and higher yield strength than those of bulk material.
Finally, single crystal Al(100) was used, instead of bulk material, to carry out copper ball impact process by using multi-scale simulation. Al(100) material is able to transform impact energy into the resilience of strain energy effectively owing to its high yield stress and low elastic modulus. Results show that the application of Al(100) material reduces the effects of stress concentration and pad “splashing” successfully during copper ball impact process.

目錄 Ⅰ
表說明 Ⅲ
圖說明 Ⅳ
摘要 Ⅴ
Abstract Ⅵ
第一章 緒論 1
1-1 研究動機與目的 1
1-2 電子構裝簡介 3
1-3 銲線接合技術簡介 4
1-3-1 超音波接合法 5
1-3-2 熱壓接合法 6
1-3-3 超音波熱壓接合法 6
1-4 文獻回顧 7
1-5 研究方法 10
第二章 分子動力學理論及數值方法 14
2-1 分子動力學理論方法 16
2-1-1 勢能函數 16
2-1-2 運動方程 18
2-1-3 Nosé-Hoover溫度修正法 20
2-1-4 原子及應力計算方法 22
2-2 分子動力學數值方法 25
2-2-1 截斷半徑法 25
2-2-2 Verlet表列法結合Cell link表列法 26
2-2-3 無因次化 27
2-3 物理模型 28
第三章 有限元素法理論 33
3-1 時間積分（Time Integration） 34
3-2 控制方程式（Governing Equation） 37
3-3 應力及應變計算方法 42
第四章 有限元素模型建構與設定 44
4-1 基本假設 44
4-2 模型設定 45
4-2-1 瓷嘴及銲球設定 46
4-2-2 基板設定 46
4-3 非線性材料模型 47
4-3-1 Biliear Isotropic Model 48
4-3-2 Standard Piecewise Linear Plasticity Model 49
4-4 材料參數設定 50
4-5 網格元素及劃分 50
4-6 銲線接合過程及邊界條件設定 51
4-7 接觸設定 52
第五章 結果與討論 60
5-1 單晶鋁（100）之應力-應變曲線 60
5-2 驗證模擬 62
5-3 有限元素銲線接合模擬之定性分析 64
5-3-1 Case 1之應力分佈變化 65
5-3-2 Case 2之應力分佈變化 66
5-3-3 Case 3之應力分佈變化 66
5-3-4 應力分佈變化之定性比較分析 67
5-4 有限元素銲線接合模擬之定量分析 68
5-4-1 Case 1之衝壓歷程曲線變化 68
5-4-2 Case 2之衝壓歷程曲線變化 70
5-4-3 Case 3之衝壓歷程曲線變化 71
5-4-4 衝壓歷程曲線變化之定量比較分析 72
第六章 結論與未來展望 82
6-1 結論 82
6-2 未來展望 84
參考文獻 86

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