In the publication (Nanoscale Research Letters 2011, 6:458), Shin et al introduced a nano-imprinting process, including fabrication of a flexible imprinting mold and using this mold, the micro- to nano-sized patterns of the original master Si template were replicated on a flat Si substrate and curved aryl substrate.
The above figure schematically show a method to make flexible mode for the following nano imprinting. Master mode is made of Silicon or fused silica. The nano- or micro structures are formed by various lithography techniques, including Electron Beam Lithography (EBL), Deep UV Lithography (DUV), Laser Writing and etching technologies (RIE, ICP, etching, etc.) (Source: Nilt.com). The patterns are then transferred to different materials, usually nickel, polymers, or hybrid polymers, such as PDMS or armorers, as templates for the following nano-imprinting as shown in the following figure.
Nano-imprinting process; transferred the pattern of master mold to the flat or curved substrates.
Source:
1) http://www.nanoscalereslett.com/content/6/1/458
2) https://www.nilt.com/masters/