Stencil lithography of superconducting contacts on MBE-grown topological insulator thin films
| Autor: | Michael Schmidt, Peter Schüffelgen, M.P. Stehno, Alexander Brinkman, Jialin Zhao, Brendan Sheehan, Bo Gao, Gregor Mussler, Martin Lanius, Thomas Schäpers, Detlev Grützmacher, Meng Wang, Daniel Rosenbach, Elmar Neumann |
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| Přispěvatelé: | Interfaces and Correlated Electron Systems |
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
Shadow mask
Materials science Ion beam Stencil lithography Nanotechnology 02 engineering and technology 01 natural sciences Inorganic Chemistry Josephson junction 0103 physical sciences Materials Chemistry Thin film 010306 general physics Surface states Topological insulator business.industry 021001 nanoscience & nanotechnology Condensed Matter Physics 22/4 OA procedure Molecular beam epitaxy (MBE) Optoelectronics Superconductor 0210 nano-technology business Molecular beam epitaxy Layer (electronics) |
| Zdroj: | Journal of Crystal Growth Journal of crystal growth, 477, 183-187. Elsevier |
| ISSN: | 0022-0248 |
| Popis: | Topological insulator (Bi 0.06 Sb 0.94 ) 2 Te 3 thin films grown by molecular beam epitaxy have been capped in-situ with a 2 nm Al film to conserve the pristine topological surface states. Subsequently, a shadow mask - structured by means of focus ion beam - was in-situ placed underneath the sample to deposit a thick layer of Al on well-defined microscopically small areas. The 2 nm thin Al layer fully oxidizes after exposure to air and in this way protects the TI surface from degradation. The thick Al layer remains metallic underneath a 3–4 nm thick native oxide layer and therefore serves as (super-) conducting contacts. Superconductor-Topological Insulator-Superconductor junctions with lateral dimensions in the nm range have then been fabricated via an alternative stencil lithography technique. Despite the in-situ deposition, transport measurements and transmission electron microscope analysis indicate a low transparency, due to an intermixed region at the interface between topological insulator thin film and metallic Al. |
| Databáze: | OpenAIRE |
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