熱超音波銅打線接合製程技術為主要之封裝製程技術之一，在此製程中銅銲球與銲墊接觸表面之間會有相對滑動而產生摩擦生熱，進而使介面溫度提高，因此會影響材料的介金屬化合物生成，進而影響接合強度，因此在研究銅打線接合製程的研究中，溫度效應是影響打線接合強度的重要因素。然而一般研究在利用數值模擬方式探討此類問題時，大多僅考慮摩擦阻力效應而未考慮摩擦生熱效應之影響。

本研究之目的在透過有限元素法建立熱超音波銅打線接合製程之三維模擬模型，探討摩擦生熱效應於銅打線接合製程之影響，並針對三個部分進行探討與分析。第一部分探討摩擦生熱效應對銅打線接合製程之接觸面應力場、應變場及溫度場的影響；第二部分探討分析超音波頻率與振幅變化於製程時間內對銅銲球與鋁銲墊應力場、應變場以及溫度場的影響；第三部分是藉由介金屬化合物厚度生成公式探討超音波頻率與振幅變化對於介金屬化合物厚度之影響。

由模擬結果得知:將摩擦生熱效應考慮進去時，其鋁銲墊之最大等效塑性應變會比未考慮摩擦生熱效應時低7.003 %，最高溫度會增加20.47 %，而最大等效應力降低了41.53 %。當模擬時間為22 μs時，超音波頻率與振幅變化對溫度場之影響不明顯；但當模擬時間至955 μs時，頻率與振幅變化對溫度場之影響會高達25.74~34.45 %。至於探討超音波頻率與振幅變化對介金屬化合物厚度之影響結果顯示，在模擬製程時間為22 μs時，當振幅為1 μm時，若頻率從60 kHz增加到240 kHz時，其介金屬化合物厚度會增加37.58 %；而當頻率為120 kHz時，若振幅從0.5 μm增加到1.5 μm時，其介金屬化合物厚度會增加26.98 %。

Thermosonic copper wire bonding process technology is one of the main IC packing process technologies. During this process, there is heat generation produced by friction resulted from relative sliding between the contact surface of copper ball and pad and the interface temperature is increased. This will affect the formation of intermetallic compound and bonding strength. Therefore, in the study of copper wire bonding process, temperature effect is an important factor on wire bonding strength. However, most of the existed research articles for studying these issues by using numerical simulation method usually considered the frictional resistance only and ignored the effect of heat generation caused by friction.
In this study, the finite element method is used and a three-dimensional simulation model is established for studying thermosonic copper wire bonding process and not only the frictional resistance effects but only the frictional thermal effects are considered. This study makes discussion and analysis on three parts. The first part discusses the effects of frictional heat generation on contact surface stress field, strain field and temperature field of copper wire bonding surface. The second part discusses the effects of variation of ultrasonic frequency and amplitude on stress field, strain field and temperature field of copper ball and aluminum pad during the process operating time. The third part analyzes the effect of variation of ultrasonic frequency and amplitude on thickness of intermetallic compounds due to intermetallic compound thickness generation formulation.
The simulated results indicated that the maxima effective plastic strain of aluminum pad with considering frictional heat generation is 7.003 % lower than the values for which not considering frictional heat generation, the maxima temperature rises 20.47 %, and the maxima effective stress drops 41.53 %. The variation of ultrasonic frequency and amplitude on the temperature field is unobvious while the simulation time is 22 μs. But if the simulation time reaches 955 μs , the temperature will be raised 25.74 % to 34.45 %. Also, when simulation time is 22 μs, ultrasonic amplitude is 1 μm and the frequency varies from 60 kHz to 240 kHz, the thickness of intermetallic increases 37.58 %. If the frequency is 120 kHz and the amplitude varies from 0.5 μm to 1.5 μm, the intermetallic thickness increases 26.98 %.

論文審定書 i
誌 謝 ii
摘 要 iii
Abstract iv
目錄 vi
表目錄 ix
圖目錄 xi
第一章 緒論 1
1.1 前言 1
1.2 打線接合技術之簡介 2
1.3 文獻回顧 3
1.3.1 銅打線接合製程之優點與缺點 3
1.3.2 銅打線接合製程之改善 7
1.3.3 銅打線接合製程之模擬分析 9
1.4 研究目標 11
1.5 論文架構 11
第二章 基礎理論介紹 17
2.1 有限元素法基礎理論 17
2.2 套裝軟體ANSYS 12.1/ LS-DYNA簡介 18
2.3 直接與順序熱固耦合原理簡介 21
第三章 研究方法 28
3.1 假設條件 28
3.2 模型之建構與設定 29
3.2.1 元素與材料模型的選用 29
3.2.2 模型幾何結構與尺寸設定 30
3.2.3 材料參數與編輯熱固耦合關鍵字文件之設定 30
3.2.4 網格劃分 32
3.2.5 邊界條件、負載方式與接觸面設定 33
3.2.6 熱功當量與計算接觸面能量設定與簡介 34
3.2.7 網格收斂性分析 35
第四章 結果與討論 47
4.1 熱超音波銅打線接合製程模擬 48
4.1.1 模擬結果與分析 49
4.1.2 有無摩擦生熱效應與高溫-常溫材料參數效應之比較 55
4.2 超音波頻率與振幅對熱超音波銅打線接合製程之影響 60
4.2.1 超音波頻率對熱超音波銅打線接合製程之影響 60
4.2.2 超音波振幅對熱超音波銅打線接合製程之影響 62
4.3 超音波頻率與振幅效應對介金屬化合物厚度之影響 63
第五章 結論與未來展望 107
5.1 結論 107
5.2 未來展望 109
參考文獻 110

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