摘要
導致電子構裝體破壞最大的主因，是由於每一層材料間熱膨脹係數不同所引起的。由於此材料性質的不匹配，會使得構裝接合面產生較大的剪應力而產生破壞。所以本篇論文的主要目的就是發展一套實驗方法來驗證有限元素模型，並改善電子構裝元件的設計。
本篇論文首先先建立一套疊紋干涉系統來偵測覆晶構裝體由溫度所產生的熱變型。在實驗的過程中，覆晶構裝體將會被給予一熱負載，接下來使用全場的疊紋干涉法來偵測覆晶構裝體切面所產生的熱變型，而熱變形將會使得覆晶構裝體產生干涉條紋。藉由此干涉條紋，即可計算其變型。另一方面，使用ANSYS®軟體，根據疊紋干涉法所量測的試件建立一個條件相同的二維有限元素模型，來計算試件的變形，並且與疊紋干涉法的結果作比較。觀察有限元素法的計算及實驗的比較，發現變形的量以及趨勢都相當接近，由此可證明有限元素的模型是正確的，接下來就可以根據這個有限元素模型分析它的應力及應變狀態，並對此模型作參數討論，尋找出較佳的設計方式。而從參數中的討論可發現，材料熱膨脹係數及楊氏係數的改變，對試件的應力及應變造成很大的影響。

Abstract
The main cause led to failure of packages is the difference of the coefficient of thermal expansion (CTE) between materials. The mismatch among every layers of packaging will cause notably shear stresses in their interconnections. The aim of the study is to develop the experimental method and the finite element model to improve the package design.
In this study, the moiré interferometry technology is built to detect the thermal deformation of flip-chip package. In the process of experiment, the flip-chip package is given a thermal load, and a whole field optical moiré interferometry is applied to detect the thermal deformation within the packages cut plane. The fringe patterns of the thermal-mechanical deformation are presented, and the deformation of the sample can be calculated by the fringe patterns.
On the other hand, a two-dimensional finite element model of flip-chip packaging according to moiré interferometry experiment is built by using the commercial software ANSYS®. Comparing the calculations of finite element method with the results of moiré interferometry experiment, it can be found that the deformation calculated by finite element method is very close to those of the moiré method. The finite element model proposed in the study is available.
Based on the finite element model, the influences of parameters, such as material properties and geometry, on thermal deformations of package are discussed. Numerical results are shown that the thermal expansion coefficient and Young’s modulus have significant effects on thermal deformations.

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