隨著科技日新月異，積體電路(Integrated circult;IC)的功能逐漸朝向系統整合以及尺寸減小為目標，其中聚醯亞胺(Polyimide,PI)軟性材料因為擁有良好的機械力學與耐高低溫特性因此常被廣泛應用於電子產業與半導體領域，能夠精確預測聚醯亞胺材料機械行為成為不可或缺的一環。數位影像相關法(Digital Image Correlation,DIC)主要利用變形前與變形後之子影像區內灰階值的變化關係來尋找變形改變的相對位置，得到位移與變形關係，且數位影像相關法的優勢在於:非接觸式量測、與可量測二維變形、具有高精確度等優點，因此廣泛運用於工程領域。本文採用數位影像相關法進行實驗量測，並針對聚醯亞胺薄膜材料黏彈性性質進行三維本構模型建立，首先利用數位影像相關法進行位移與應變精確度分析，分析數位影像相關法量測精確度，以及確認數位影像相關法處理流程與位置長度選擇。接著對聚醯亞胺薄膜材料利用潛變實驗進行黏彈性行為量測，並且利用時間-溫度重疊原理(time-temperature principle)進行主曲線建立，再利用柔量與蒲松比黏彈性行為變化，進一步探討剪切鬆弛模數、體積鬆弛模數之黏彈性行為反應。推導出三維黏彈性模型，完整描述材料黏彈性行為。最後透過三維黏彈性模型進行有限元素法模擬不同實驗下之應變變化，並與數位影像相關法實驗量測結果進行比較，驗證實驗得到之聚醯亞胺薄膜材料黏彈性本構模型。

Polyimide (PI) materials are widely used in the electronics industry and semiconductor fields because of their good mechanical properties and high and low-temperature resistance. This study applys digital image correlation (DIC) to measure the displacements and strains in tensile tests of PI. Because DIC is non-contact measurement, it can measure the two-dimensional deformation and has high accuracy. The study first evaluated the accuracy of DIC displacement and strain measurements, and confirmed the analysis flow of DIC and the selection of gauge length. The DIC is then applied to measure viscoelastic behaviors of the PI thin film under creep tests, and a three-dimensional viscoelastic model was developed to fully describe the viscoelastic behavior of the PI thin film. Finally, finite element simulation based on the three-dimensional viscoelastic model was used to simulate the strain responses under various loading conditions, and the numerical results were compared to experimental measurements to verify the viscoelastic constitutive model of the PI thin film.

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