近年來市場的需求，造成電子零件往輕薄與多功能化演進，其中扇出型面板級封裝(Fan-Out Panel Level Packaging, FO-PLP)是能符合市場需求的選項之一。面板級封裝在製程中會有溫度的升降溫，因而使封裝產生翹曲現象。其中列出兩種產生翹曲的原因，一種是面板級封裝結構是由多種材料組成，而不同材料間的熱膨脹係數不同，製程中升降溫會導致膨脹收縮程度不同而造成翹曲;另一種是封裝環氧樹脂(Epoxy Molding Compound)在升溫製程中會發生固化反應導致體積收縮產生翹曲。若是在此階段產生之翹曲量過大則會造成後續製程的困難，故本研究將會專注於使用有限元素法(Finite Element Method)預測翹曲值。
本研究使用有限元素法(Finite Element Method, FEM)來進行建立三維模型，並且在環氧模壓樹脂材料使用經實驗驗證過之等效熱膨脹係數(Equivalent CTE)，此舉為簡化該材料在固化反應產生的體積收縮等化學效應，最後成功建立扇出型面板級封裝之模型。
FEM相較於實驗雖然可以節省大量的時間與成本，但常因人為疏失導致結果不同，並且在改變結構尺寸下也必須重新建立模型。因此本研究為了減少上述情況，藉由極度隨機樹(Extremely Randomized Trees) 集成學習演算法來預測不同封裝尺度下的翹曲量，該演算法特點為對於大規模數據具有運算快速的特點。首先會透過有限單元法建立出不同幾何尺寸之扇出型面板級封裝模型的訓練數據庫，接著機器學習透過這些訓練數據庫來學習，機器學習在完成學習後即可快速的預測出隨便一個幾何尺寸面板級封裝的翹曲值。
然而從眾多的文獻中可以發現扇出型面板級封裝的翹曲是一個非對稱的形狀，影響此結果可能有眾多原因，例如，封裝環氧樹脂厚度不均勻，封裝環氧樹脂厚度不同會有不同的收縮率，當有一側收縮率不同即會影響到其他地方的變形行為，因而有機率產生不對稱的翹曲，另外在模壓成型(Compression Molding)過程中，封裝環氧樹脂是透過接觸來進行加熱固化，而封裝環氧樹脂在固化過程當中會產生體積收縮，進而產生翹曲並影響接觸面積，因此加熱溫度會有所差異，進而造成封裝環氧樹脂的固化反應不相同。
因此本研究將深入探討造成非對稱翹曲的原因，例如製程的影響等。同時透過有限元素法建立三維模型，來去模擬製程差異產生的非對稱翹曲。

In recent years, the demand of the market has resulted in the evolution of thin and multi-functional electronic components. Fan-Out Panel Level Packaging (FO-PLP) is one of the options that can meet the market demand. Panel-level packaging will have temperature rise and fall during the process, which will cause warpage. There are two reasons for warpage. One is that the panel-level packaging structure is composed of a variety of materials, and the coefficients of thermal expansion of different materials are different. The temperature rise and fall during the process will lead to different degrees of expansion and contraction, resulting in warpage; the other is Epoxy Molding Compound will undergo a curing reaction during the heating process, resulting in volume shrinkage and warpage. If the amount of warpage generated at this stage is too large, it will cause difficulties in the subsequent process, so this research will focus on using the Finite Element Method to predict the warpage value.
In this study, the finite element method was used to build a 3D model, and the experimentally verified Equivalent CTE was used in the epoxy molding compound. This is done to simplify chemical effects such as volume shrinkage of the material during the curing reaction. Finally, the model of the fan-out panel-level package was successfully established.
Although FEM can save a lot of time and cost compared with experiments, the results are often different due to human error, and the model must be re-established when the structure size is changed. Therefore, in order to reduce the above situation, this study uses the Extremely Randomized Trees ensemble learning algorithm to predict the amount of warpage at different packaging scales. The algorithm is characterized by its fast operation on large-scale data. First, a training database for fan-out panel-level packaging models of different geometric sizes will be established through the finite element method, and then machine learning will learn through these training databases. Machine learning can quickly predict the warpage value of a panel-level package of any geometric size after completing the learning.
However, from many literatures, it can be found that the warpage of the fan-out panel level package is an asymmetric shape. There may be many reasons for affecting this result. For example, the thickness of the package epoxy resin is not uniform, and the thickness of the package epoxy resin will be different. There are different shrinkage rates. When the shrinkage rate of one side is different, it will affect the deformation behavior of other places, so there is a chance to produce asymmetric warpage. In addition, in the process of compression molding, the encapsulation epoxy resin is passed through the contact During the curing process, the encapsulated epoxy resin will shrink in volume, which will cause warpage and affect the contact area. Therefore, the heating temperature will be different, and the curing reaction of the encapsulated epoxy resin will be different.
Therefore, this study further explores the causes of asymmetric warpage, such as the influence of the process. At the same time, a three-dimensional model is established by the finite element method to simulate asymmetric warpage caused by process differences.

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