The Effect of Moisture on the Equivalent Strain for the Redistributed Chip Package through the 3-D Finite Element Analysis

• Main Authors: Yi-PingFang, 方怡平
• Other Authors: Rong-Sheng Chen
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/26896265656566976477

碩士 === 國立成功大學 === 工程科學系 === 102 === In recent years, the moisture in the package has become the essential issue for research. The residual moisture always leads to the popcorn failure and then interfacial delamination within materials in the reflow process. Hence, the entire process of the package is simulated by finite element analysis. In this paper, the RCP with PoP (Package on Package) package is constructed by stacking the upper very fine pitch ball grid array (VFBGA) with RCP’s multiple redistribution layers technology on the lower stack package ball grid array (SPBGA). First of all, ANSYS, the finite element software is adopted for simulation analysis. Based on JEDEC, the RCP with PoP model is subject to two conditions, 30oC/60%RH and 85oC/60%RH in the moisture absorption process. In the reflow process, to the moisture distribution and residual moisture with moisture desorption are predicted. Secondly, the different conditions of moisture absorption, 85oC/60%RH and 85oC/85%RH, are subjected to compare with previous results and investigate the effect of different relative humidity and temperature on the moisture diffusion. Finally, the variance analysis is conducted to investigate the impacts of the CTE, Young’s modulus and coefficient of moisture expansion of underfill of RCP with PoP package on the structure. Meanwhile, the sensibility of various parameters for the package is recognized. The results indicate the CTE of underfill on the Von Mises Strain for package is largest and the value is 0.051476. However, the high sensitivity of each parameter for the package is the coefficient of moisture expansion of underfill, and the value is 11.3%.