晶圓重組的封裝技術相對於傳統封裝技術，所建構出的晶片尺寸更小、擁有更好的I/O接點數與性能並且能降低生產成本，因此具備著極大的優勢潛力。製程中必須經歷一系列壓模、後熟化、卸除載盤等製程，然而在過程中包含多組製程與材料參數的綜合效應，例如溫度、時間與材料的相關特性，倘若在參數組合挑選不佳的情況下，缺陷就可能隨之產生。因此，本文擬透過有限元素數值方法針對製程中的晶粒偏移(die-shift)與晶圓翹曲(wafer warpage)現象作細部的分析，將完整之製程加入至數值模型的分析中，包含壓模過程到後續缺陷的光學檢測的部分，研究中將搭配相關實驗以獲取材料參數以及進行上述缺陷的驗證，進階探討各參數的效應以減少晶粒偏移與結構翹曲的現象。經由整體製程的分析與評估，觀察到壓模封膠(molding compound)與其關聯的固體力學因素為影響晶粒偏移與翹曲的關鍵因子，並藉由數值模型進行綜合探討後，提出改善晶粒偏移與結構翹曲以及減少不對稱晶圓翹曲的建議，並建立製程中的關鍵參數分析以達到參數最佳化，以及提升整體重組製程良率的目標。

Wafer reconstitution is a vital process for serving as a buffer to decouple the processing developments between IC fabrication and electronics packaging. By this approach, the IC packaging is then independent from the chip processing. However, such a process brings numerous mechanical loadings during molding and curing phases. Without carefully planning, failures such as die-shifting and excessive wafer warpages are frequently reported and it induces problems for subsequent processing. In this work, it is desired to examine the key factor of die-shift and wafer warpage by performing finite element analyses, as well as essential parameters study. Preliminarily, the die-shift and warpage problems are deduced as interaction of fluid load, thermal expansion, shrinkage of molding compound and viscoelastic effect. To have a deeper insight, complete finite element analyses of the entire Recon procedure, from molding and thermal-related processes to inspection-related gravity effect, have been constructed to examine the involved phenomenon comprehensively. Compared with experiment, simulation of FE model has a consistent tendency with actual situation and is close to the observed defects. It is found that thermal-mechanical factors such as thermal expansion and residue stress have more influence on die-shift than mold flow effect. In addition, FE result shows that issue of unsymmetrical warpage is related to layout of dies and overall stiffness of reconstituted wafers. Furthermore, by parameters study based on FE models, key parameters with high sensitivity could be identified to optimize the Recon process. The proposed improving solutions are expected to reduce 20 to 30 percentage of initial die-shift and warpage for a better yield rate.

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