Reflow profile simulation by finite element method for a BGA package

Author

Liang, Shen ; Mingxiang, Wang ; YongHong, He ; Fai, Lam Tim ; Jiang Yu Qi

Author_Institution

Dept. of Microelectron., Soochow Univ., Suzhou, China

fYear

2005

fDate

30 Aug.-2 Sept. 2005

Firstpage

419

Lastpage

422

Abstract

During reflow process, solder ball temperature profile is a concern, but it is difficult to direct measure the temperature. In this study, a forced convective airflow reflow furnace was analyzed. Measured profiles from two typical BGA packages were simulated successfully. Temperature profile of package surface has been compared with that of solder balls. Temperature distribution among solder ball array has been observed and analyzed. It has been found that impinging jet airflow model provides appropriate convective heat transfer coefficient that can be applied to profile simulation successfully. Dominant heat transfer mechanism is vertical thermal conduction from package top surface to solder ball, while other heat transfer mechanism also have notable effects on solder ball temperature. Solder ball array layout has a significant effect on temperature uniformity of solder balls. A uniform distribution can be obtained when all the balls are located under chip area.

Keywords

ball grid arrays; finite element analysis; heat transfer; reflow soldering; semiconductor process modelling; temperature distribution; BGA package; convective heat transfer coefficient; finite element method; forced convective airflow reflow furnace; heat transfer mechanism; impinging jet airflow model; package surface; reflow profile simulation; solder ball array layout; solder ball temperature profile; temperature distribution; temperature uniformity; thermal conduction; Belts; Boundary conditions; Finite element methods; Furnaces; Heat transfer; Heating; Packaging; Semiconductor device modeling; Temperature distribution; Temperature measurement;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic Packaging Technology, 2005 6th International Conference on

Print_ISBN

0-7803-9449-6

Type

conf

DOI

10.1109/ICEPT.2005.1564717

Filename

1564717