The numerical simulation and optimization of PBGA package

• Main Authors: Chia-Sheng Lo, 羅家昇
• Other Authors: Gien-Huang Wu
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/10227285322289614271

碩士 === 國立成功大學 === 機械工程學系碩博士班 === 93 === This research is using 3-dimensional model simulation to analyze the thermal-mechanical and heat transfer behavior of EPBGA by applying finite element analysis ANSYS 8.1. EPBGA model consists of seven parts, they are heat spreader, molding compound, chip, substrate, thermal vias, solder ball and PCB board. The model is constructed by different materials and each material has its own function to demonstrate its characteristic. For analysis on thermal-mechanical behavior, the viscoplastic behavior of solder ball is modeled using Anand model, the viscoelastic behavior of molding compound is simulated by Maxwell model, the other parts are using linear elastic model to simulate. As a result, analysis of transformation behavior of EPBGA can be carried out under a 125℃~-40℃heat cycling environment. For heat spreading analysis, the beginning temperature of EPBGA and surrounding area is 25℃, the heat dissipation per volume unit of chip is 0.03 W/mm3. When it reaches stable condition, analysis of heat transfer behavior and stress and strain distributions will be carried out. Moreover, this research is using Grey relational analysis and Taguchi’s orthogonal arrays to achieve the design of optimization of multiple responses. The required responses are the solder ball response and the stress and strain distributions of EPBGA. Accompanying suitable control factors, the experimental data of Taguchi’s orthogonal arrays can be analyzed, on the other hand, by applying Grey relational analysis to perform simple calculations and constructing response table and response graph, optimal design can be achieved.