摘要
针对光电耦合器在电路板组件生产过程中被氯化物腐蚀和在终端客户使用过程中被硫化物腐蚀的两个典型案例,通过对器件机械开盖、对器件外围引脚及内部芯片进行SEM和EDX检测找到了腐蚀路径,并分别通过开展高温高湿试验、湿硫磺蒸汽环境试验重现了腐蚀失效模式,找到了失效根本原因,同时也证明了无卤助焊剂替代、先涂敷三防漆再点胶等生产工艺改进措施的有效性,为分析解决光电耦合器腐蚀失效问题提供参考。
Two typical cases of optical couplers corroded by chloride in the production of print circuit board module and by sulfide in the use of end customers were analyzed in this paper.After mechanical De-cap,SEM and EDX were used to scan the outer pin and inner die and finally found out the path of corrosion.Through high temperature and high humidity test,as well as humid sulfur vapor test respectively to reproduce the failure mode,this paper found out the failure root cause,also proved the effectiveness of the process improvements such as halide flux alternative,conformal coating application prior to glue,and provided the reference for corrosion failure analysis and prevention of optical couplers.
作者
刘大喜
周峰
Liu Daxi;Zhou Feng(Zhuzhou CSR Times electric CO.,LTD.,Zhuzhou,Hunan,412001)
出处
《印制电路信息》
2020年第5期52-54,共3页
Printed Circuit Information
关键词
光电耦合器
腐蚀
工艺改进
Optical Coupler
Corrosion
Process Improvement
