PCB Creep Corrosion and Board Design Considerations
Authors: He Jingqiang, Gao Feng, Tu Yunhua, and Liu Sang Company: Huawei Technologies Co., Ltd. Date Published: 10/24/2010
Abstract: According to the Restriction of Hazardous Substance (RoHS) legislation, the electronics industry is changing to lead-free rapidly, this lead to the application of many new materials and processes, such as solder alloy, the fluxes, PCB surface finishes and reflow curves etc. At the same time, a particular type of failure termed creep corrosion was published frequently in recent years, which is mainly due to environmental exposure to sulfur-containing gases. The effects of the following factors on creep corrosion were compared: surface finishes, post-dip of ImAg, sealant of ENIG, SMD/NSMD/plugged PTH, and wave-soldering fluxes, and the morphology of copper sulfides were also discussed.