| AVS 66th International Symposium & Exhibition | |
| Advanced Ion Microscopy and Ion Beam Nano-engineering Focus Topic | Thursday Sessions |
| Session HI+NS-ThM |
| Session: | Novel Beam Induced Material Engineering and Nano-Patterning |
| Presenter: | André Beyer, Bielefeld University, Germany |
| Authors: | A. Beyer, Bielefeld University, Germany M. Westphal, Bielefeld University, Germany S. Stephan, Oldenburg University, Germany D. Emmrich, Bielefeld University, Germany H. Vieker, Bielefeld University, Germany K. Chen, Jinan University, Guangzhou, China G. Razinskas, Würzburg University, Germany H. Gross, Würzburg University, Germany B. Hecht, Würzburg University, Germany M. Silies, Oldenburg University, Germany A. Gölzhäuser, Bielefeld University, Germany |
| Correspondent: | Click to Email |
Plasmonic nanostructures are essential for controlling and directing light on the nanoscale. While fabrication techniques like standard electron beam lithography (EBL) methods or focused ion beam (FIB) milling with Ga+ ions are approaching their limit in the 10-nm-regime, ion beam milling with He+ ions is capable of milling features below 6 nm [1,2]. In this contribution, we give two specific examples of helium-ion milled plasmonic nanostructures: (i) gold bowtie antennas milled from 100 nm thick polycrystalline gold films on mica substrates and (ii) nanoslit cavities in chemically-synthesized 40 nm thick single-crystalline gold flakes [2]. Both examples benefit from a combined approach using a Ga+ FIB for milling large features and employing the fine resolution of the helium ion microscope (HIM) for milling small features. We will discuss different patterning strategies to optimize the writing speed and minimize substrate swelling. In addition, our approach to quantify the sizes of milled gaps will be shown. It is based on low dose imaging in combination with substantial line-profile averaging which we applied to few-hundred-nanometer-long homogeneous helium-ion milled lines.
[1] H. Kollmann et al., Nano Letters 14, 4778 (2014).
[2] K. Chen et al., Nanoscale 10, 17148 (2018).