Freiburg 2019 – wissenschaftliches Programm
FM 63: Poster: Enabling Technologies: Quantum Materials, Quantum Dots, Quantum Wires, Point Contacts and Superconducting Systems
FM 63.19: Poster
Mittwoch, 25. September 2019, 16:30–18:30, Tents
Nanostructuring diamond with self-organized metal droplets as etching mask — •Patricia Quellmalz, Christian Giese, Peter Knittel, and Christoph Nebel — Fraunhofer Institute for Applied Solid State Physics, 79108 Freiburg, Germany
Diamond has many applications due to its outstanding properties, notably the mechanical hardness, wide optical window or chemical inertness. Nitrogen vacancy centers bring diamond further into focus, especially for quantum technology. Electron beam lithography is state-of-the-art to pattern nanometer-sized features. This technique offers high resolution but is laborious and expensive. A viable alternative is patterning via dewetted metals. By yielding high-aspect diamond nanostructures with enormous surface enlargement, it is of great interest for electrochemical or quantum applications (e.g. supercapacitors or room-temperature hyperpolarisators). We present this fast and low-cost way to nanostructure wafer-scale, polycrystalline diamond (PCD). The PCD is patterned top-down by inductively coupled plasma reactive ion etching (ICP-RIE) employing randomly distributed metal droplets as mask. These nanometer-sized droplets form after dewetting a thin evaporated metal film via rapid-thermal annealing. Various metals and layer thicknesses for mask formation on in-house grown layers of intrinsic and heavily boron doped PCD are investigated in addition to different plasma etching parameters. The material shows a dark black color, which points to strong light absorbance in the visible due to the nanostructuring. We achieve an increase in surface area with micrometer deep coral-like structures of some ten-nanometer size.