本文主要利用有限元素分析軟體ANSYS14.0來模擬覆晶封裝組合體FCBGA於加速溫度循環中錫球的熱機械行為與疲勞壽命。
在本模擬中，首先利用ANSYS建立模型，並設定各元件材料參數完成網格化，由於錫球為非線性黏塑材料，因此以Anand’s model來描述錫球的變化行為，而其他材料視為彈性以提高求解效率，之後施以加速溫度循環負載，觀察錫球在負載過程中的塑性應變變化(plastic strain range)，並將結果代入Coffin-Manson疲勞壽命預測公式來探討錫球的可靠度。
在結果與討論中分成三大部分，第一部分探討含鉛錫球(60Sn40Pb)的分析結果。首先觀察各個錫球的應力、應變與翹曲分布，找出發生最大von Mises應變的關鍵錫球，再分析關鍵錫球於熱負載過程中應力與應變的變化，藉由Coffin-Manson equation，計算出含鉛錫球疲勞壽命。
第二部分為參數設計，考慮三種不同型組合體對錫球疲勞壽命的影響，以及不同高分子組件與散熱組件的參數設計對錫球疲勞壽命的影響。我們可以藉由分析結果得知哪些因素對FCBGA錫球疲勞壽命影響顯著。
第三部分為含鉛與無鉛錫球壽命的比較，觀察不同無鉛材料的關鍵錫球在整個熱負載過程中的應力、應變還有遲滯迴圈的變化，並比較含鉛與無鉛錫球的疲勞壽命。

This paper uses finite element software ANSYS14.0 to analyze the Flip-Chip Ball Grid Array packaging (FCBGA) under accelerated thermal cycling loading. We will observe the thermal mechanical behaviors of the solder balls and discuss the fatigue life of the FCBGA.
In this simulation, we first use ANSYS to establish the FCBGA model, and apply different materials to each component to finish meshing. For the nonlinearly viscoplastic property of the solder ball, the Anand’s model is used to describe the deformation of the solder ball. However, to increase the solving efficiency, linearly elastic materials can be used to describe other components. After applying accelerated thermal cycling (ATC) loads, we observe the plastic strain range of the solder ball during ATC loads. Eventually, we use the Coffin-Manson equation to predict the fatigue life and reliability of the solder ball.
Results and Discussion is divided into three parts, the first part is about the tin-lead solder ball (60Sn40Pb) analysis results. First, we observe the stress, strain and warpage distribution of each solder ball, to figure out the critical solder ball with the maximum von Mises strain, and then we analyze the stress and strain of the critical solder ball during the whole ATC loads. Eventually the Coffin-Manson equation is used to calculate the fatigue life of the solder ball.
The second part is the parameters design considering the effect of the three types of different FCBGA assembly on the fatigue life of solder ball, and the effect of different polymer components and heat spreader assembly on the fatigue life of solder balls. Analyzing the results we can understand what factors affect the fatigue life of solder ball FCBGA significantly.
The third part is the fatigue life comparison between tin-lead and lead-free solder balls. We focus on the stress, strain and hysteresis loop plot of the critical solder ball, and then compare the fatigue life between the tin-lead and lead-free materials.

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