Title :
A comprehensive finite element model for simulating reflow profile of a BGA package
Author :
Liang, Shen ; Mingxiang, Wang ; YongHong, He ; Fai, Lam Tim ; YuQi, Jiang
Author_Institution :
Dept. of Microelectron., Soochow Univ., Suzhou
Abstract :
During reflow process, it is the temperature of solder balls that is the most concerned. However, it is difficult to directly measure its temperature and reflow profile is obtained by measuring the package surface temperature. Based on our previous study of reflow profile simulation (Shen Liang et al., 2005), a comprehensive finite element model (FEM) has been built for precisely simulating relow profile of solder balls in a forced convective airflow reflow furnace. It is found that impinging jet airflow model provides appropriate estimation of convective heat transfer coefficient as a boundary condition for FEM. Phase transition effect of solder balls has been successfully included and evident influence on solder ball´s temperature has been observed. Length of Cu metallization which connects solder balls to outside power/signal sources is found to influence temperature of specific solder balls. Size of printing circuit board (PCB) on which package located is also found to considerably affect reflow profile around its peak temperature
Keywords :
ball grid arrays; finite element analysis; reflow soldering; solders; temperature measurement; BGA package; Cu metallization; PCB; convective heat transfer coefficient; finite element model; forced convective airflow reflow furnace; printing circuit board; reflow profile simulation; solder balls; Boundary conditions; Finite element methods; Furnaces; Heat transfer; Metallization; Packaging; Printed circuits; Printing; Semiconductor device modeling; Temperature measurement;
Conference_Titel :
High Density Microsystem Design and Packaging and Component Failure Analysis, 2006. HDP'06. Conference on
Conference_Location :
Shanghai
Print_ISBN :
1-4244-0488-6
DOI :
10.1109/HDP.2006.1707605
