光电耦合器二次塑封工艺的实验结果分析与理论研究  

Analysis of Experimental Results and Theoretical Study of Secondary MoldingProcess of Optocoupler

作　　者：李李 肖雪芳 兰玉平 LI Li;XIAO Xuefang;LAN Yuping(School of Opto-electronics and Communication Engineering,Xiamen University of Technology,Xiamen 361024,China;Xiamen Hualian Electronics Corp.,LTD,Xiamen 361008,China)

机构地区：[1]厦门理工学院光电与通信工程学院,福建厦门361024 [2]厦门华联电子股份有限公司,福建厦门361008

出　　处：《东莞理工学院学报》2024年第5期68-75,共8页Journal of Dongguan University of Technology

基　　金：福建省自然科学基金(2021J05267)。

摘　　要：针对二次塑封工艺对光电耦合器性能影响的研究尚不完善的问题,对MSL1级环境下的二次塑封的光耦封装效果进行实验和有限元仿真研究。利用超声扫描显微镜等实验设备,对回流焊、内点胶、环氧塑封料和等离子清洗四种工艺下光电耦合器塑封器件的分层情况进行分析,测试电流传输比,并对环氧塑封料应力参数对分层的影响进行研究,从而优化二次塑封封装工艺条件。研究结果表明回流焊峰值温度设置在Tp=245℃到Tp=250℃可以改善分层问题,芯片胶高在0.4 mm以上及0.3 mm以下会造成光耦严重的分层,采用热应力参数相匹配的塑封料和在二次塑封前增加等离子清洗工艺,清洗功率设置为300 W,清洗时间为15 s,是改善光耦封装分层的有效措施。Aiming at the problem that the research on the influence of secondary plasticizing process on the performance of photocoupler is still imperfect,this paper carries out experimental and finite element simulation research on the effect of photocoupler encapsulation of secondary plasticizing in MSL1 level environment.Using ultrasonic scanning microscope and other experimental equipment,we analyze the delamination of photocoupler encapsulated devices under four processes of reflow soldering,internal dispensing,epoxy encapsulant and plasma cleaning,test the current transfer ratio,and study the effect of epoxy encapsulant stress parameter on delamination,so as to optimize the conditions of the secondary plastic encapsulation process.The results show that the reflow soldering peak temperature set at Tp=245℃to Tp=250℃can improve the delamination problem;the chip adhesive height above 0.4 mm and below 0.3 mm will cause serious delamination of the optocoupler;Using the plastic sealing material matching thermal stress parameters and increasing the plasma cleaning process before the secondary plastic sealing,the cleaning power is set to 300 W and the cleaning time is 15 s,which is an effective measure to improve the optocoupler package.

关 键 词：光电耦合器 封装分层 点胶 回流焊 等离子清洗 

分 类 号：TN305[电子电信—物理电子学]