关键词: 陶瓷小外形封装, 焊点寿命, 热疲劳寿命, 焊锡爬升, 根部填充

Abstract: Taking solder joints of Ceramic Small Outline Package (CSOP) as the research object, this study quantitatively analyzed the effects of two critical parameters in the soldering process—solder climb height and lead root filling volume—on solder joint lifespan. By combining finite element simulations with the Coffin-Manson life prediction model, the impact of varying solder joint morphologies on reliability was systematically investigated. The results indicate that solder climb significantly weakens the stress relief capability of the leads. When the solder climbs beyond the first and second stress relief bends of the lead, the thermal fatigue lifespan of the solder joints decreases by 3.95% and 49.29%, respectively. Furthermore, increasing the solder filling volume at the lead root from 0.0252 mm³ to 0.0411 mm³ enables the formation of a robust solder joint profile, effectively alleviating stress concentration and enhancing the thermal fatigue lifespan by up to 366.97%. This study provides essential theoretical foundations and optimization guidelines for process parameter design related to solder joint morphology.

Key words: ceramic small outline package, solder joint life, thermal fatigue life, solder climbing,  root filling