Electroforming for replicating nanometer-level smooth surface.

We proposed and developed a new electroforming process for the replication of surfaces having nanometer-level smoothness. In the electroforming process, the separation method plays an important role in preventing the degradation of the surface morphology. The key point in this process is the fabrication of a metal film as an electrode on the master surface. Cr atoms are deposited by an arc plasma deposition method and act as a binding material. Subsequently, a nickel film is fabricated by electron beam deposition to form an electrode. Electrodeposition is then carried out in a nickel sulfamate bath. By controlling the density of Cr atoms on the master surface, the binding strength between the nickel film and master surface can be adjusted, which makes it possible to separate the metal film from the master surface smoothly. As a result, a surface roughness of 0.22 nm (root mean square) has been achieved in a 64 microm x 48 microm area of a replicated surface.