Programmable set-up for electrochemical preparation of STM tips and ultra-sharp field emission cathodes

0477724 - ÚPT 2018 RIV NL eng J - Journal Article
Knápek, Alexandr - Sýkora, Jiří - Chlumská, Jana - Sobola, D.
Programmable set-up for electrochemical preparation of STM tips and ultra-sharp field emission cathodes.
Microelectronic Engineering. Roč. 173, APR 5 (2017), s. 42-47. ISSN 0167-9317. E-ISSN 1873-5568
R&D Projects: GA MŠMT(CZ) LO1212
Institutional support: RVO:68081731
Keywords : field emission cathode * STM tip * electrochemical etching
OECD category: Chemical process engineering
Impact factor: 2.020, year: 2017

This paper describes a newly designed set-up which is intended for automated preparation both for STM tips and for ultra-sharp field emission cathodes made of polycrystalline and single crystal tungsten in laboratory conditions. The newly designed set-up incorporates electrochemical etching of a wire in the surface layer of an electrolyte and also the so called drop-off method which consists of two steps and requires more precise wire and current setting. Additionally, the method was extended for polycrystalline wires of tungsten using a special cut-off algorithm, which deals with variable etching speed for various crystallographic orientation of the current grain. Produced tips are examined using scanning low energy electron microscopy as for the surface and by the occurrence of electron field-emission as for the geometry based on the Fowler-Nordheim analysis. STM performance of the produced tip is discussed and examined as well.
Permanent Link: http://hdl.handle.net/11104/0273973