热风整平产品回流焊时pad变色的研究与解决

HASL tin-copper-nickel reflow process product pad color defect research and solution

在应对电子产品无铅化的过程中,所有电子产品载体的PCB无铅表面处理工艺必然顺应历史潮流,在PCB无铅化热风整平工艺深度引入暴露出诸多问题,本文主要阐述无铅锡铜镍热风整平工艺产品在下游客户端做回流焊接工艺时,经过1-2次高温环境后,pad表面变色发黄的问题做深入分析与研究,从pad焊锡厚度,高温环境、喷锡助焊剂,抗氧化锗的含量的影响入手,通过理论与实践研究变色原理及解决方案。

In dealing with electronic products lead-free process, all electronic products lead-free PCB carrier surface treatment processes must conform to the historical trend, in the lead-free HASL PCB process reveals the depth of the introduction of many problems, this paper mainly expounds the copper-free Solder Nickel-HASL process products in the downstream clients to do when the reflow soldering process, after a 1-2 times after the hightemperature environments, pad surface, yellowish discoloration problems do in-depth analysis and research, from the solder pad thickness, hightemperature environments, HAL Flux , anti-oxidation effects of Ge content to start, through the theory and practice of color theory and solutions.