Development of electro-copper plating with nanodiamonds for electronic interconnects in advanced packaging

Abstract

In order to advance a technology suitable for fabrication of fine pitch interconnects using copper electro plating, we developed the composite of copper (Cu) and nanodiamonds (NDs). Electro-Cu plating coatings obtained by adding NDs to the electro-Cu plating bath were demonstrated to maintain a smaller crystallite size compared to the plating coatings that NDs were not added. Moreover, in case of the electro-Cu plating coatings obtained by adding NDs, smoothness of the plating coating surface and hardness of the plating coating with time course have been improved, and the electro conductivity has been improved by up to 16%. The composite material of electro-Cu plating and NDs which we developed showed the potential that it could be expected for application to fine pitch interconnects in an advanced packaging technology.