為了提高產品良率，可靠度為電子封裝產品相當重要的指標之一，但進行可靠度測試需要耗費大量的時間、設備與資金，因此為了降低研發成本，使用模擬軟體進行可靠度分析是一個選擇，但以往的分析研究較少將製程對可靠度的影響考慮進去。本文將利用模流分析軟體Moldex3D將製程、結構、材料等多項因素影響考慮在內，尤其針對環氧樹脂封裝材料(epoxy molding compound, EMC)於充填注膠與後熟化製程後之性質進行研究，發展一套包含可靠度預測在內完整的IC封裝產品數值分析方法。
由於EMC在注膠過程中體積會受到壓力、溫度與熟化度的影響而有所變化，本研究在IC元件的分析過程中，以本實驗室發展出之P-V-T-C模型來形容此段變化，而後熟化製程因材料性質會因溫度與熟化度影響而變化因此使用雙轉化因子黏彈模型計算封裝後的翹曲與殘留應力，並於後熟化分析施加負載，模擬封裝產品被放在烤箱烘烤加壓的情形，另外還探討了不同環境條件對於翹曲結果的影響。接著再以後熟化模擬之殘留應力結果作為初始條件進行熱循環模擬，分析元件經歷溫度循環後的應力分佈情形，並選用Modified Coffin-Manson fatigue model作為可靠度計算模型。
從後熟化模擬結果可以看到，若使用讓封裝體壓平貼於地面負載條件設定，改變負載方向與大小對於翹曲而言幾乎沒有影響。若讓封裝體處在完全沒有拘束的狀況，僅固定封裝體中央點的位置，則翹曲量雖有稍微增大，但不多。比較後熟化後的翹曲量模擬值與實驗值可以發現其變形趨勢是正確的，皆為凹向下，但在翹曲量上短邊會有較大的誤差。在可靠度分析的部分，所使用到的應力模擬結果與模型參數則需要透過實驗或使用其他分析軟體加以佐證。

In order to improve the production yield rate, reliability is one of the important indicators of electronic packaging products. In the past research, however, influence of fabrication process was rarely taken into consideration. In this thesis, mold flow analysis software Moldex3D is used to develop a series analysis procedure for IC package products and reliability prediction. The effects of many factors, including process, structure, and materials were being taken into account. Especially for epoxy molding compound, namely EMC, is studied on its properties during the molding and post mold cure (PMC) processes.
This paper adopted P-V-T-C equations, which considers both volume shrinkage due to thermal mismatch and chemical shrinkage to predict the amount of warpage and residual stresses after mold filling process. Next, dual shift factor model for viscoelastic analysis was used to model the PMC process and predict the amount of warpage and residual stresses after PMC. And the influence of different PMC process conditions and loading conditions on the warpage results are discussed. The residual stresses after PMC simulation are set as initial condition for reliability analysis and then the stress distribution after two thermal cycles is analyzed.
It is observed that the deformed shape of simulation and experiment results after PMC were consistent. Both are concave downwards. In comparison with experiments results, the error of warpage simulation results were between 10% and 50%. The biggest error was found at the short direction. During two thermal cycles, it is assumed that plastic deformation occurs in the lead frame. To calculate reliability of IC package, plastic strain of the maximum stress position is considered as the damage information. Modified Coffin-Manson fatigue model is selected for calculation.

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