Based on surface mount products virtual assembly technology,the solder joint reliability of plastic ball grid array (PBGA) was studied. Four process parameters,including the upper pad diameter,the stencil thickness,th...Based on surface mount products virtual assembly technology,the solder joint reliability of plastic ball grid array (PBGA) was studied. Four process parameters,including the upper pad diameter,the stencil thickness,the chip weight on a single solder joint and the lower pad diameter were chose as four control factors. By using an L25(56) orthogonal array the PBGA solder joints which have 25 different process parameters’ levels combinations were designed. The numerical models of all the 25 PBGA solder joints were developed and the finite element analysis models were setup. The stress and strain distribution within the PBGA solder joints under thermal cycles were studied by finite element analysis,and the thermal fatigue life of PBGA solder joint was calculated using Coffin-Manson equation. Based on the calculated thermal fatigue life results,the range analysis was performed. The results of study show that that the impact sequence of the four factors from high to low on the fatigue life of PBGA solder joints are the stencil thickness,the upper pad diameter,the lower pad diameter and the chip weight on a single solder joint; the best level combination ofprocess parameters that results in the longest fatigue life is the lower pad diameter of 0.6 mm,the stencil thickness of 0.175 mm,the chip weight on asingle solder joint of 28×10 -5 N and the upper pad diameter of 0.5 mm.展开更多
基金Funded by Science Foundation of Guangxi Zhuang Autonomous Region (No.02336060) .
文摘Based on surface mount products virtual assembly technology,the solder joint reliability of plastic ball grid array (PBGA) was studied. Four process parameters,including the upper pad diameter,the stencil thickness,the chip weight on a single solder joint and the lower pad diameter were chose as four control factors. By using an L25(56) orthogonal array the PBGA solder joints which have 25 different process parameters’ levels combinations were designed. The numerical models of all the 25 PBGA solder joints were developed and the finite element analysis models were setup. The stress and strain distribution within the PBGA solder joints under thermal cycles were studied by finite element analysis,and the thermal fatigue life of PBGA solder joint was calculated using Coffin-Manson equation. Based on the calculated thermal fatigue life results,the range analysis was performed. The results of study show that that the impact sequence of the four factors from high to low on the fatigue life of PBGA solder joints are the stencil thickness,the upper pad diameter,the lower pad diameter and the chip weight on a single solder joint; the best level combination ofprocess parameters that results in the longest fatigue life is the lower pad diameter of 0.6 mm,the stencil thickness of 0.175 mm,the chip weight on asingle solder joint of 28×10 -5 N and the upper pad diameter of 0.5 mm.
基金National Science and Technology Major Project of the Ministry of Science And Technology of China(No.2013YQ240803)Shanxi Programs for Science and Technology Development(Nos.20140321010-02,201603D121040-1)Scientific and Technological Innovation Programs of Higher Education Institutions of Shanxi Province(No.2013063)