薄电解质层下覆铜层压板和化学镀镍/浸金印刷电路板的电化学迁移行为

Electrochemical Migration Behavior of Copper-Clad Laminate and Electroless Nickel/Immersion Gold Printed Circuit Boards under Thin Electrolyte Layers.

作者信息

Yi Pan, Xiao Kui, Ding Kangkang, Dong Chaofang, Li Xiaogang

机构信息

Corrosion and Protection Center, University of Science and Technology Beijing, Beijing 100083, China.

State Key Laboratory for Marine Corrosion and Protection, Luoyang Ship Material Research Institute, Qingdao 266101, China.

出版信息

Materials (Basel). 2017 Feb 8;10(2):137. doi: 10.3390/ma10020137.

DOI:10.3390/ma10020137

PMID:28772497

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5459160/

Abstract

The electrochemical migration (ECM) behavior of copper-clad laminate (PCB-Cu) and electroless nickel/immersion gold printed circuit boards (PCB-ENIG) under thin electrolyte layers of different thicknesses containing 0.1 M Na₂SO₄ was studied. Results showed that, under the bias voltage of 12 V, the reverse migration of ions occurred. For PCB-Cu, both copper dendrites and sulfate precipitates were found on the surface of FR-4 (board material) between two plates. Moreover, the Cu dendrite was produced between the two plates and migrated toward cathode. Compared to PCB-Cu, PCB-ENIG exhibited a higher tendency of ECM failure and suffered from seriously short circuit failure under high relative humidity (RH) environment. SKP results demonstrated that surface potentials of the anode plates were greater than those of the cathode plates, and those potentials of the two plates exhibited a descending trend as the RH increased. At the end of the paper, an electrochemical migration corrosion failure model of PCB was proposed.

摘要

研究了覆铜层压板（PCB-Cu）和化学镀镍/浸金印刷电路板（PCB-ENIG）在含有0.1 M Na₂SO₄的不同厚度薄电解质层下的电化学迁移（ECM）行为。结果表明，在12 V的偏置电压下，离子发生反向迁移。对于PCB-Cu，在两块板之间的FR-4（板材）表面发现了铜树枝状晶体和硫酸盐沉淀。此外，在两块板之间产生了铜树枝状晶体并向阴极迁移。与PCB-Cu相比，PCB-ENIG在高相对湿度（RH）环境下表现出更高的ECM失效倾向，并遭受严重的短路故障。SKP结果表明，阳极板的表面电位大于阴极板的表面电位，并且随着RH的增加，两块板的电位呈下降趋势。在论文结尾，提出了PCB的电化学迁移腐蚀失效模型。