US Patent 7365918 Fast x-ray lenses and fabrication method therefor

A fabrication process for zone plate lenses is based on controlled thin layer deposition for fabricating structures as small as 2 nanometers (nm) in width, and potentially smaller. The substrate for deposition will take the form of a precision hole, fabricated in a substrate, such as silicon by electron beam lithography and subsequent reactive ion etching. A controlled layer deposition is then used to form the required zone plate structure. A subsequent thinning process is used to section the hole and produce a zone plate with the required layer thicknesses.