摘要
[目的]化学微蚀作为前处理工艺,被广泛应用在印制电路板(PCB)制造的各大环节。[方法]分别采用硫酸-过硫酸钠(用SA-SP表示)、硫酸-双氧水(用SA-HP表示)和甲酸-氯化铜(用FA-CC表示)3种体系对挠性印制电路板(FPCB)的细线路进行微蚀。通过激光光谱共聚焦显微镜(LSCM)对比了采用不同体系时的微蚀量、微蚀速率及微蚀后线路的表面粗糙度。通过扫描电镜(SEM)研究了不同微蚀体系处理前后铜线路的表面形貌,以及微蚀液对化学镀镍的影响。[结果]3种体系微蚀能力大小顺序为:SA-SP>SA-HP>FA-CC。采用不同微蚀液时铜线的表面粗糙度均随微蚀时间延长而增大。采用甲酸-氯化铜体系微蚀后铜线表面有少量氯化亚铜形成。微蚀液对化学镀镍效果的影响显著。采用硫酸-双氧水体系微蚀时镍镀层光亮,但有渗镀现象;采用甲酸-氯化铜体系微蚀时,化学镍渗镀现象严重;采用硫酸-过硫酸钠微蚀时,细线路化学镍渗镀现象得到有效控制,但镀层较暗。[结论]可尝试通过在化学镀镍液中添加光亮剂来提高镀层光亮度。
[Introduction]Chemical microetching is widely used as a pretreatment in different phases during manufacturing of printed circuit boards(PCB).[Method]The fine lines on flexible printed circuit boards(FPCB)were microetched respectively in different electrolytes i.e.sulfuric acid-sodium persulfate electrolyte(coded as SA-SP),sulfuric acid-hydrogen peroxide electrolyte(coded as SA-HP),and formic acid-copper chloride electrolyte(coded as FA-CC).The microetching degree,microetching rate,and surface roughness of fine line after being microetched were compared by laser spectroscopy confocal microscopy(LSCM).The surface morphologies of copper lines before and after being microetched with different electrolytes and the effects of different electrolytes on electroless nickel plating were studied by scanning electron microscopy(SEM).[Result]The microetching capacity of the three electrolytes was in the following descending order:SA-SP>SA-HP>FA-CC.The surface roughness of copper lines was increased with the extending of microetching time no matter which electrolyte was used.A small amount of cuprous chloride was formed on copper line surface after being microetched with the FA-CC electrolyte.The composition of microetching electrolyte had great effect on the electroless nickel plating of copper lines.The nickel coating electrolessly plated on the copper lines microetched with the SA-HP electrolyte was bright,but an excessive nickel plating phenomenon occurred.The excessive nickel plating on the copper lines was severe when microetching with the FA-CC electrolyte,but effectively controlled when microetching with the SA-SP electrolyte.However,the Ni coating plated electrolessly on the copper lines microetched in the SA-SP electrolyte was dark.[Conclusion]It is recommended adding brightening agent to the electroless nickel plating bath to increase the brightness of Ni coating.
作者
秦伟恒
郝志峰
胡光辉
罗继业
陈相
王吉成
徐欣移
QIN Weiheng;HAO Zhifeng;HU Guanghui;LUO Jiye;CHEN Xiang;WANG Jicheng;XU Xinyi(School of Light Industry and Chemical Engineering,Guangdong University of Technology,Guangzhou 510006,China)
出处
《电镀与涂饰》
CAS
北大核心
2024年第4期1-8,共8页
Electroplating & Finishing
基金
广东省重点领域研发计划项目(2023B0101010002)。
关键词
挠性印制电路板
细线路
微蚀
化学镀镍
表面粗糙度
flexible printed circuit board
fine line
microetching
electroless nickel plating
surface roughness
