LIANG Ying, HUANG Chun-yue, ZOU Ya-mei, et al. Stress and Strain Analysis and Optimization of Micro-scale CSP Solder Joints Based on Torsion Load[J]. Acta Electronica Sinica, 2020, 48(10): 2033-2040.
DOI:
LIANG Ying, HUANG Chun-yue, ZOU Ya-mei, et al. Stress and Strain Analysis and Optimization of Micro-scale CSP Solder Joints Based on Torsion Load[J]. Acta Electronica Sinica, 2020, 48(10): 2033-2040. DOI: 10.3969/j.issn.0372-2112.2020.10.022.
Stress and Strain Analysis and Optimization of Micro-scale CSP Solder Joints Based on Torsion Load
The finite element analysis model of micro-scale chip scale package(CSP) solder joints is set up and stress and strain analysis are performed under torsion load
and the verification experiment is also carried out.The influence of solder joint diameter
solder joint diameter
pad diameter and solder joint height on the torsion stress and strain of micro-scale CSP solder joints are analyzed.The solder joint material
solder joint diameter
pad diameter and solder joint height are selected as design variables;29 groups of solder joints with different levels are designed and simulated by response surface methodology.The regression equation of solder joint torsion stress and structural parameters is established.The structural parameters of solder joint are optimized based on the regression equation and genetic algorithm.The results show that the maximum torsion stress and strain occurs with the solder joints material of SAC305
the maximum solder joint torsion stress and strain decreases with the increase of solder joint diameter and pad diameter
and increases with the increase of solder joint height;the optimal combination of solder joint level is the solder joint material of SAC305
the solder joint diameter of 0.22mm
the pad diameter of 0.14 mm and the solder joint height of 0.14mm
and simulation verification result shows the maximum stress of the solder joint decreases by 3.7MPa after optimization.