Hee-Tae Jung

The development of large-area, high-resolution nano-patterning with high-aspect-ratios is a challenging problem that must be solved for potential applications in high performance nanoscale devices, such as nanoelectronics, optics, micro-fluidics, light-emitting devices and bio-sensing devices. To date, nano-imprinting, and soft-, e-beam, dip-pen (DPN), and soft-building block-lithography have been primarily used in such applications. Below, we describe a new patterning technique that enables fabrication of ultra high-resolution and high-aspect-ratio patterns of various shapes. We have named the technique “secondary sputtering lithography.” In this methodology, target materials are selectively sputtered onto the surface of a pre-patterned polymer by using low Ar+ ion bombarding energies, based on the angular distribution of target particles by ion-beam bombardment. After removal of the pre-patterned polymer, high-aspect-ratios and high-resolution patterns of target materials are created. Unlike previous nano-fabrication techniques described thus far, this technique has several notable advantages. Firstly, it the simple processing procedure results in efficient formation of high-resolution (ca. 10 nm) patterns with high-aspect-ratios (ca. 15) over large-areas. Secondly, the technique can be applied to patterning most semiconducting, metallic and dielectric materials. Finally, 3-dimensional nanostructures with complex topologies, such as hole-cylinder, cup and triangle-cone shaped surfaces, can be easily fabricated by controlling feature of the polymer pattern. Thus, the novel patterning technology represents a new concept for fabricating future high performance nanoscale devices. We discuss a wide range of applications using this approach.