電子封裝結構中，高分子材料扮演保護矽晶積體電路不受外在環境影響的重要角色。當封裝結構中高分子材料受到製程或使用情況下之溫度變化時，由於其與矽晶間之熱膨脹係數或收縮的不匹配，容易導致元件發生翹曲。對堆疊式封裝產品而言，在整個製程及電路堆疊迴銲過程中，元件需維持一定的平坦度，倘若封裝體本身翹曲量太大或是連接元件製程產生過大翹曲變化，將會造成堆疊困難進而影響製程良率及可靠度。
本文針對堆疊式封裝體中環氧樹脂封膠，利用實驗方法量測其材料性質並建立黏彈性三維本構模型。實驗包含拉伸式與扭轉式動態機械分析，所量測封膠黏彈性機械性質包括與時間－溫度相關的楊氏儲存模數和剪切儲存模數，然後利用數值轉換近似法找到輸入有限元素軟體需要的黏彈性本構模型，並搭配其它材料的彈性模型套入有限元素法計算中，模擬封裝體在受溫度變化下的翹曲量且與陰影疊紋實驗結果比對。然而由實驗所得封膠黏彈性三維本構模型，因可能的實驗誤差而沒有得到理想蒲松比趨勢，但經過擬合修正實驗儲存模數主曲線後，套入有限元素軟體中模擬所得翹曲量趨勢與實驗量測較為吻合。從模擬結果發現，芯基板熱收縮為造成翹曲主要原因，且底填膠與防焊綠漆材料也會造成翹曲量趨勢的變化，而封膠在高溫下因結構處於橡膠態對翹曲行為影響並不大。

In this thesis an experimental procedure for characterizing three-dimensional viscoelastic behavior of epoxy molding compound (EMC) is presented. By using both tensile and torsional dynamic mechanical analyses (DMA) and thermal mechanical analyses (TMA), the viscoelastic constitutive model of a low-filler-percentage EMC is developed. Finite element analyses incorporating the viscoelastic EMC constitutive behavior are conducted to simulate warpage evolution of a package-on-package (PoP) device during solder reflow process. The numerical results are compared to shadow Moiré warpage measurements for validating the constitutive model.

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