Optimization of 3D patterning by Ga implantation and reactive ion etching (RIE) for nanoimprint lithography (NIL) stamp fabrication

Abstract

Nanoimprint lithography (NIL) has the unique capability to replicate 3D patterns in one single step. However, to exploit this feature high quality, 3D patterned NIL stamps are required. While grayscale electron-beam lithography suffers from resolution limitations due to proximity effects, focused ion beam (FIB) milling and gas assisted etching is inherently slow. We introduce a new 3D patterning process based on FIB implantation and subsequent reactive ion etching (RIE) for NIL stamp fabrication. The presented process is more than 100 times faster than FIB milling. We demonstrate NIL stamps with complex 3D patterns and resolutions down to 50nm fabricated with this process.