Fabrication and application of a full wafer size micro/nanostencil for multiple length-scale surface patterning

A tool and method for flexible and rapid surface patterning technique beyond lithography based on high-resolution shadow mask method, or nanostencil, is presented. This new type of miniaturized shadow mask is fabricated by a combination of MEMS processes and focused ion beam (FIB) milling. Thereby apertures in a 100-500 nm thick low-stress silicon nitride membrane in the size range from < 100 nm to > 100 μm were made. The stencil device is mechanically fixed on the surface and used as miniature shadow mask during deposition of metal layers. Using this method, aluminum micro- and nanostructures as small as 100 nm in width were patterned. The deposited micro- and nano-scale structures were used as etch mask and transferred into a sub-layer (in our case silicon nitride) by dry plasma etching. High-resolution shadow masking can be used to create micro/nanoscale patterns on arbitrary substrates including mechanically fragile or chemically active surfaces.