影响QFN封装器件焊接质量的因素

Factors of Influencing QFN Component Soldering Quality

QFN封装具有体积小、质量轻以及良好的电和热性能等优点。由于QFN封装的元件底部没有焊料球,其与PCB的电气和机械连接是通过在PCB焊盘上印刷焊膏,回流焊接形成焊点而实现的;因此,对PCB焊盘设计和表面组装工艺技术提出了新的要求和挑战。本文从印制板设计、QFN器件保护、印刷工艺以及回流焊温度曲线设置与控制等方面,阐述了影响QFN封装焊接技术的各个因素,以提高QFN封装器件焊接质量及可靠性。

The QFN package has the advantages of small volume, light weight, good electrical and thermal properties. At the bottom of the QFN package components there is solder ball, the electrical and mechanical connection between QFN component and PCB are achieved by paste printing on the PCB pad and reflow soldering,therefore, some new requirements and challenges to the PCB pad design and surface mount technology have been put forward. Considering the printed circuit board design, QFN device protection, printing technology, reflow soldering temperature curve setting and control etc. , the paper expounds the factors influencing the QFN package of welding technology, and then improves the welding quality and reliability of QFN packaging device.