Published October 8, 2012 | Version v1
Journal article

High quality ultrathin Bi2Se3 films on CaF2 and CaF2/Si by molecular beam epitaxy with a radio frequency cracker cell

  • 1. Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305 (United States)
  • 2. Department of Applied Physics, Stanford University, Stanford, California 94305 (United States)
  • 3. Department of Physics, Stanford University, Stanford, California 94305 (United States)
  • 4. School of Physics and Astronomy, Tel Aviv University, 69978 Tel Aviv (Israel)

Description

We report a method to fabricate high quality Bi2Se3 thin films using molecular beam epitaxy with a radio frequency cracker cell as an atomic selenium source. With Se-to-Bi ratios close to exact stoichiometry, optimal layer-by-layer growth of high quality Bi2Se3 thin films with smooth surfaces has been achieved on CaF2(111) substrates and Si(111) substrates with a thin epitaxial CaF2 buffer layer (CaF2/Si). Transport measurements show a characteristic weak-antilocalization magnetoresistance in all the films, with the emergence of a weak-localization contribution in the ultrathin film limit. Quantum oscillations, attributed to the topological surface states have been observed, including in films grown on CaF2/Si.

Additional details

Identifiers

Publishing Information

Journal Title
Applied Physics Letters
Journal Volume
101
Journal Issue
15
Journal Page Range
p. 153105-153105.4
ISSN
0003-6951
CODEN
APPLAB

Optional Information

Notes
(c) 2012 American Institute of Physics