以镍为种子层的半加成工艺研究

Study of semi-additive process with nickel as the seed layer

文章中采取化学镀镍和选择性电镀铜工艺，开发了一种新型的半加成法制作精细线路的工艺技术。首先在环氧树脂基材上化学沉积一层非常薄的镍层，然后在镍层表面贴抗镀干膜，曝光、显影后露出线路凹槽。进行电镀铜在镍表面生长出需要的精细线路，然后退去抗镀干膜，快速蚀刻掉种子镍层。由于镍与铜的金属活动性不同，选取的蚀刻液能蚀刻镍而对铜没有腐蚀，从而得到完全没有侧蚀的精细线路。

A new semi-additive process to fabricate fine line with neat shape in printed circuit board was developed by combining electroless nickel plating and selective copper deposition. Nickel was chemical deposited on the dielectric substrate as a seed layer. Copper line was eleetorodeposited selectively on the seed layer with resistant coat fabricated by film pasting, exposure and development. Then the resistant coat was stripped by sodium hydroxide solution, revealing the area of nickel layer without the copper line which would be etched by nickel stripping solution in the end. As the difference of the metal activity between nickel and copper, the copper line wouldn＇t be etched. By this means the fine line will have neat shape and accurate width as designed.