Wafer scale nano-membrane supported on a silicon microsieve using thin-film transfer technology

A new micromachining method to fabricate wafer scale nano-membranes is described. The delicate thin-film nano-membrane is supported on a robust silicon microsieve fabricated by plasma etching. The silicon sieve is micromachined independently of the thin-film, which is later transferred onto it by fusion bonding, thus providing flexibility in design and processing steps. Using this thin-film transfer technique, nano-membranes down to 50nm thickness are fabricated. The fabrication of different kinds of membranes made of inorganic, metallic and polymer materials is presented here. Apart from dense nanomembranes, perforated membranes are fabricated using this modular approach. One of the main areas of interest for such membranes is in fluidics, where the small thickness and high strength of the supported nano-membranes is a big advantage