Fabrication and characterization of single crystalline diamond nanopillars with NV-centers

• Optimum pillar diameter of 195 nm determined.
• Angled side walls are less critical than expected.
• A reproducible lithographic process for nanopillar production was implemented.
• Reduced pillar taper due to changes in the ICP settings.
• Pillar structures have different fluorescence intensities for different pillar Diameters.

Single crystalline diamond nanowires of different sizes and shapes were fabricated with electron beam lithography and inductively coupled plasma etching using oxygen. Titanium and chromium have been used as etching mask, where titanium appeared to be more chemically resistant. We were able to fabricate nanowires from 60 nm diameter to 200 nm with a length of approximately 1 μm. As the nanowire should be used in the future as a waveguide for the NV fluorescence originating from the apex of the structure, simulations were done with Comsol Multiphysics in order to determine the dependency between shape and guidance properties.