QFN器件的组装工艺

Assembly Technology of QFN Device

QFN器件的侧面若未形成良好的焊点,则无法通过目视检查判断其焊接的质量问题,并且QFN组装技术目前没有统一标准规范,为后期出现组装缺陷埋下隐患。针对上述问题,通过分析印制板焊盘及钢网设计对后期组装具有影响的主要因素,拟定工艺试验方案,设计试验样件,进行工艺试验。试验结果表明,通过对QFN器件焊盘设计以及钢网开孔设计技术进行配合优化,成功实现了No-Pullback类型QFN器件侧面完全上锡的组装效果,提高了QFN器件的质量和可靠性,并且能通过目视检查判定其组装的质量。

If there is no good solder joint on the side of QFN device,the soldering quality can’t be judged by visual inspection,and there is no unified standard for QFN assembly technology,which lays hidden dangers for later assembly defects.In view of the above problems,the main factors that affect the later assembly of PCB pad and steel mesh design is analyzed,the process test scheme is formulated,and the test samples and the process tests are designed.The test results show that through the optimization of the QFN bonding pad design and the steel mesh opening design,the assembly effect of no-pullback QFN with tin on the side is successfully achieved,which improves the quality and reliability of QFN and judges the assembly quality by visual inspection.