本文將ACF非線性材料特性於金凸塊製程中的力學分析過程分為三個步驟：(1)進行壓合，本過程之力學分析視樹脂黏著劑為流體狀態不承受壓合力，全部壓合負載由其內部以Mooney-Rivlin橡膠雙係數超彈性材料模式的導電粒子承受，(2)加入樹脂黏著劑於FEM分析，以搭配步驟1之力平衡，建立結構物的壓合下之應力分布，(3)進行降溫及卸壓。依參考文獻提供的材料數據，上述所有的步驟金凸塊皆設定為多線性等向硬化模式，矽晶片、玻璃基板、PI、鋁墊片等材料設為彈性，步驟二、三考慮樹脂黏著劑並設定其為線黏彈性模式，配合以廣義麥斯威爾模式所表示之體積、剪力鬆弛模數及以WLF方程式所定義的時間-溫度平移因子等材料參數，並將導電粒子設定為線彈性模式。分析結果顯示固定降溫歷程中，不同降壓速度對其Y向應力分布及大小之影響不大，存放30秒後，其應力鬆弛現象亦不顯著。

　　在金凸塊及導電粒子接面應力上，比較ν(t)在0.35及0.475的波松比函數與常數0.35發現，後者會得到較低壓應力及較高剪應力，對結構破壞準則而言可得較保守的評估。波松比與CTE的偶合作用對平均接面壓應力的影響大於對平均接面剪應力的影響。金凸塊寬度在85至125 μm、高度在10至18μm的範圍內，其接面應力大小及分布並無太大的差異。

　This paper divides ACF nonlinear material properties in the mechanical analysis of Au bump bonding process course into Three steps: (1)To press, in this step this mechanics analysis consider resin as fluid state can not bear pressure, all pressure is born by hyperelastic material of a two coefficients Mooney-Rivlin rubber conductive particle of inside ,(2)Add the resin and analyse in FEM. According to match step 1 force equilibrium state, set up the same structure stress distribution. (3)Cooling and unloading. Material parameters are offered in the references, the gold bump in all step above-mentioned is considered as multilinear isotropic material, Si chip, glass, polyimide, Al pad are considered as elastic material. It is linear viscoelastic model with Bulk, Shear relaxation modulus which builded by Generalize Maxwell Model and WLF time-temperature shift factors equation to consider the resin in second, third step, and conductive particle consider as elastic material. The analysis results shows that in the cooling process, different unloading speed doesn't effect the value and distribution of Y stress. After preserving for 30 seconds, its stress relaxation is also not apparent.

　For the stress on the bump and the conductive particle interface, compare the Poisson ratio function ν(t) which the value between 0.35 and 0.475 with the Poisson ratio constant 0.35, the latter will result lower Y stress and higher shear stress, It's more conservative for structure failure criterion. The Poisson ratio and CTE coupling has more effective to the average interface compression stress then the average interface shear stress. Bump width in the range of 85μm to 125 μm, height in range of 10μm to 18μm, doesn't effect the interface stress value and distribution very much.

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