Fabrication of n-shaped micro copper structures through localized electrochemical deposition

Abstract

Localized electrochemical deposition is a cost-effective technique for fabricating 3D microstructures. In this study, to fabricate a complete n-shaped micro copper structure, multi-layer deposition was adopted, and the v-groove was removed by an asymmetric trajectory. Thereafter, the merging mechanism of the n-shaped structure was analyzed using COMSOL simulations. The results demonstrated that multilayer deposition was suitable for connecting the copper column in different directions; the optimized layer was 15 layers with a height of 15 μm. The simulation showed that the v-groove was caused by the speed difference between the column and bumps, and an asymmetric trajectory with a height difference of 55 μm could suppress vertical deposition and remove the v-groove.