摘要
对塑封后的20μm细径铜丝超声键合焊点进行了高温存储可靠性研究.采用SEM观察了老化后键合焊点界面微观组织及金属间化合物,采用EDS对反应物的成分进行了分析.结果表明,200℃老化9天或250℃老化9 h,键合焊点界面生成了大量Cu-Al金属间化合物,并出现可见的微裂纹和Kirkendall孔洞;250℃老化16 h后,环氧塑封料中微量的Sb元素与铜球焊点发生反应,生成以Cu3Sb为主的反应物;当老化时间超过49 h,铜丝破碎,铜键合焊点产生严重腐蚀.250℃老化超过24 h或300℃老化超过4 h会发生银迁移现象.
The high temperature strorage reliability of Cu bonds formed with 20 μm copper wire by ultrasonic bonding process after encapsulation with epoxy molding compounds was investigated.SEM was used to analyze the interfacial microstructure and IMCs on the bonding interface after thermal aging.EDS was used to identify the IMCs compositions.A great amount of Cu/Al IMCs as well as micro-cracks and Kirkendall voids are found on the bonding interface after thermal aging with 9 days at 200 ℃ and with 9 hours at 250 ℃.With 16 hours aging at 250 ℃,the element Sb which is decomposed from the epoxy molding compounds started to react with Cu ball bonds to form Cu3Sb.When the aging time is more than 49 hours at 250 ℃,Cu wire loop is broken and serious corrosion is found in Cu ball bond.Furthermore,Ag migration phenomenon occurs if the aging time is more than 24 hours at 250 ℃ or 4 hours at 300 ℃.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2013年第2期13-16,113-114,共4页
Transactions of The China Welding Institution
基金
国家自然科学基金资助项目(50705021)
中央高校基本科研业务费专项资金资助项目(HIT.NSRIF.2010/20)
