Plasma etching of superconducting Niobium tips for scanning tunneling microscopy
arXiv:1404.5370 · doi:10.1063/1.4887795
Abstract
We report a reproducible technique for the fabrication of sharp superconducting Nb tips for scanning tunneling microscopy (STM) and scanning tunneling spectroscopy. Sections of Nb wire with 250 m diameter are dry etched in an SF plasma in a Reactive Ion Etcher. The gas pressure, etching time and applied power are chosen to produce a self-sharpening effect to obtain the desired tip shape. The resulting tips are atomically sharp, with radii of less than 100 nm, and generate good STM images and spectroscopy on single crystal samples of Au(111), Au(100), and Nb(100), as well as a doped topological insulator BiSe at temperatures ranging from 30 mK to 9 K.
arXiv commentSee supplemental file for conductance map linked to Fig. 5(b)
References in corpus (15)
- Topological Insulators
- Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
- Unconventional superconductivity on a topological insulator
- Atomically precise placement of single dopants in Si
- Two Gap State Density in MgB: A True Bulk Property or A Proximity Effect?
- Proximity effect at the superconductor - topological insulator interface
- On the use of STM superconducting tips at very low temperatures
- Probing the superfluid velocity with a superconducting tip: the Doppler shift effect
- Josephson scanning tunneling microscopy
- Scanning tunneling spectroscopy with superconducting tips of Al
- A 30 mK, 13.5 T scanning tunneling microscope with two independent tips
- Probing the superconducting condensate on a nanometer scale
- The fabrication of reproducible superconducting scanning tunneling microscope tips
- Fabrication and characterization of scanning tunneling microscopy superconducting Nb tips having highly enhanced critical fields
- Disorder effects in pnictides : a tunneling spectroscopy study