PATTERNING OF NON-CONVEX SHAPED NANOSTRUCTURES
Methods of making nano-scale structures with geometric cross-sections, including convex or non-convex cross-sections, are described. The approach may be used to directly pattern substrates and/or create imprint lithography templates or molds that may be subsequently used to directly replicate nano-shaped patterns into other substrates, such as into a functional or sacrificial resist to form functional nanoparticles.
1 . An imprint lithography template comprising a patterning surface having features, the features having geometric cross-sections and at least one corner having a radius of curvature of less than 25 nm.
2 . The template of claim 1 wherein the geometric cross-section is non-convex.
3 . The template of claim 1 wherein the geometric cross-sections are polygonal.
4 . The template of claim 1 wherein the features of the imprint template are raised.
5 . The template of claim 1 wherein the features of the imprint template are recessed.
6 . A method of forming nanostructures having geometric cross-section using the imprint lithography template of claim 1 .
7 . The method of claim 6 further comprising the formation of a patterned layer having features corresponding to the template features and having a residual layer thickness that allows for shape retention of the geometric feature during pattern transfer.
8 . The method of claim 7 wherein the residual layer thickness less than 15 nm.