Rapid fabrication of nanostructured surfaces using nanocoining

A new process for creating high quality ordered arrays of nanofeatures called nanocoining is presented. A diamond die with a structured area of nanofeatures (1600 features in a 20 μm × 20 μm area) is used to physically transfer features to a mold surface. The die is attached to an actuator capable of producing an elliptical tool-path, the dimensions of which are process dependent and enable the die to match velocity with the moving mold during contact to avoid dragging the nanostructured area along the mold surface (smear). Nanocoining process parameters are discussed which enable indents to be indexed precisely to completely cover target areas. Techniques for die alignment and depth control are also required to create large areas (339 mm2) of nanofeatures in short times (∼20 min). Nanocoining experiments were performed at 1 kHz (1000 indents or 1.6 million features per second) on a flat electroless nickel sample. UV curable replicates were then created from the nickel mold and both the mold and replicate were examined in an SEM and AFM.