随着产品小型化的发展,微小LP封装器件的应用越来越广泛,其中中央焊盘焊点空洞率成为影响产品功能的关键因素.主要研究镍金表面处理印制电路板上LP封装器件中央焊盘锡铅焊点空洞问题.介绍了焊点空洞的产生机理、焊接工艺难点及空洞控制方法,提出了优化焊盘设计、优化模板开孔设计、强化焊膏使用控制、控制焊膏印刷精度、控制贴装精度和优化焊接工艺参数等六大保证措施.经试验验证,同时采取6项措施后,有效地控制了镍金表面处理的PCB上LP封装器件的中央焊盘焊点空洞问题.%With the development of product miniaturization, LP packaging has been widely used. The key factor that infl uences the function of product is the ratio of void in solder joint of LP packaging. Mainly research the void problem in solder joint between central tin lead pad of LP packaging and the Ni/Au surface of PCB. Introduce the reasons of occurring void in solder joint, the diffi culty of soldering and the way to control the void. Put forward six measures to control the void, including optimizing the pad design, optimizing the stencil design, controlling how to use solder paste, controlling the precision of printing soldering paste, controlling the precision of chip placement, optimizing soldering parameters. The tests show that the void problem is effectively controlled by taking the six measures.
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