电子封装塑封材料中水的形态  

MORPHOLOGY OF THE WATER IN PLASTIC ELECTRONIC PACKAGING MATERIALS

作　　者：彩霞[1] 黄卫东[1] 徐步陆[1] 程兆年[1] 

机构地区：[1]中国科学院上海微系统与信息技术研究所

出　　处：《材料研究学报》2002年第5期507-511,共5页Chinese Journal of Materials Research

基　　金：国家自然科学重点基金资助项目19834070

摘　　要：利用实验和Fick扩散方程模拟塑封材料对水的吸收过程,得到水汽在塑封材料中的扩散系数和饱和浓度. 塑封材料中的水分子存在于高分子链围成的微孔洞中,并与高分子聚合物以氢键相连. 当塑封材料中水汽浓度达到饱和时,在水分子进入的有效体积内,水汽的密度为标准状态下水蒸气密度的100倍,为液态水密度的8％,这表明在塑封材料中水分子以一种特殊的液态水形态存在. 在一定的水汽浓度下,在界面处的微孔洞中水气液两相共存. 在两相共存的微孔洞中由于水分子争夺高分子的氢键使高分子与芯片表面的二氧化硅层的结合减弱,逐步扩展形成可以观察到的分层.The absorption and desorption processes of moisture in plastic material were studied. The diffusion coefficient and the saturate concentration were determined by experimental and simulation results with Pick law. The water molecules inside plastic material were bonded with polymers by the hydrogen bond in the micro-voles formed by the polymer chain. Under the saturate concentration, the moisture density in effective volumes is 100 times greater than vapor density in standard state, is 8% the density of liquid water. The water in plastic material is a special liquid. The delamination happens when liquid and gas states coexist. There were water and vapor in the micro-voles when the moisture concentration is high enough. The strength of the interface between the plastic material and the die was reduced by the bonding of water molecule with polymers, which caused the delamination.

关 键 词：电子封装 水 形态 塑封材料 吸水 塑料封装 环氧树脂 

分 类 号：TN305.93[电子电信—物理电子学]