Conformal surface nanostructuring of microparts based on nanosphere lithography

Abstract

We report on the development of a process chain for the conformal surface-structuring at sub-microscale of complex parts. More especially, the main objective was to manufacture functional microparts with engineered sidewall topographies. The solution proposed is based on the surface structuring of the sidewalls of resin molds used in the LIGA process (Lithography Galvanik Abformung). The surface structuring was achieved by depositing sub-micrometer particles prior to electroforming step. The length scale of the structures produced was controlled by the size of the particles deposited. The particle deposition process was monitored by using a quartz crystal microbalance and optimized on flat surfaces. It was successfully applied to produce structured nickel phosphorus LIGA parts. The structured surfaces produced were also used to create liquid infused surfaces, having low wetting hysteresis.