Title :
Thermomechanical reliability analysis and optimization for MEMS packages with AuSn solder
Author :
Zhang, Rui ; Shi, Hongbin ; Ueda, Toshitsugu ; Zhang, Jiong ; Dai, Yuehong
Author_Institution :
Grad. Sch. of Inf., Production & Syst., Waseda Univ., Fukuoka, Japan
Abstract :
Thermal stress formed in the solder of the microelectromechanical systems (MEMS) sensor during the reflow soldering process due to the coefficients of thermal expansion (CTE) mismatch between the different materials. As the package needs to be hermetically sealed to protect the device from outside environmental effects, the local stress concentration would eventually cause cracks in the solder and influence the hermeticity. In this study, we present the thermo-mechanical analysis of the AuSn90 solder with low temperature co-fired ceramic (LTCC) package using Comsol Multiphysics. Thermal residual stress distribution in the solder after the reflow soldering process was simulated. According to the result, the maximum von Mises stress was found and several possible ways for minimizing the stress in the solder and improving the thermo-mechanical reliability were discussed.
Keywords :
ceramic packaging; gold alloys; hermetic seals; microfabrication; microsensors; reflow soldering; reliability; solders; thermal analysis; thermal expansion; thermal stresses; tin alloys; AuSn; CTE mismatch; Comsol Multiphysics; LTCC package; MEMS package optimization; coefficients of thermal expansion; cracks; environmental effects; hermetic seal; local stress concentration; low temperature co-fired ceramic package; maximum von Mises stress; microelectromechanical system sensor; reflow soldering process; solder; thermal residual stress distribution; thermo-mechanical analysis; thermomechanical reliability analysis; Heating; Materials; Mathematical model; Micromechanical devices; Reliability; Stress; Thermal stresses; FEA; MEMS; optimal designing; reliability; thermal stress;
Conference_Titel :
Quality, Reliability, Risk, Maintenance, and Safety Engineering (ICQR2MSE), 2012 International Conference on
Conference_Location :
Chengdu
Print_ISBN :
978-1-4673-0786-4
DOI :
10.1109/ICQR2MSE.2012.6246348