挠性PCB精细线路化学镍金加工能力提升研究

Improvement of electroless nickel and immersion gold process on fine line for flexible PCB

PCB化学镍金工艺是指在PCB裸铜焊盘表面通过活化钯核,先通过无电镀镍制作化学镍层,再通过化学浸金获得化学金层的一种可焊性最终表面涂覆工艺。它既具有良好的接触导电性和良好的装配焊接性能,还能够与其他表面涂覆工艺配合使用。随着电子行业发展,其作用和市场日益显得无可替代,随着行业发展需求,线路间距愈发精细,挠性PCB需求30/30μm线路间距,已超常规化学镍金工艺加工能力,存在渗镀缺陷,导致产品短路。文章分析了线路铜箔结构对化学镍金渗镀的贡献,化学镍金参数对化学镍金渗镀的制作原理,给出挠性PCB精细线路渗镀解决方案,做出详细的论述。

PCB chemical nickel gold process refers to a solderable final surface coating process in which a chemical nickel layer is made by activating palladium core on the surface of PCB bare brazing pad,and then a chemical gold layer is obtained by chemical leaching.It not only has good contact conductivity and good assembly and welding performance,but also can be used with other surface coating processes.With the development of the electronics industry,its role and the market position are increasingly irreplaceable.With the development of the industry demand,line spacing is becoming more and more fine.Flexible PCB with 30/30um line spacing demand has exceeded conventional chemical nickel gold process processing capacity.There are plating defects,resulting in short circuit of the product.This paper analyzes the contribution of line copper foil structure to chemical nickel gold plating,the production principle of chemical nickel gold parameters,gives the solution of flexible PCB fine line plating,and makes a detailed discussion.