Dielectric properties of thin Cr2O3 films grown on elemental and oxide metallic substrates

Authors

Ather Mahmood, University of Nebraska - LincolnFollow
Mike Street, University of Nebraska - LincolnFollow
Will Echtenkamp, University of Nebraska-LincolnFollow
Chun Pui Kwan, SUNY University at BuffaloFollow
Jonathan P. Bird, SUNY University at BuffaloFollow
Christian Binek, University of Nebraska-LincolnFollow

Date of this Version

4-2-2018

Citation

PHYSICAL REVIEW MATERIALS 2, 044401 (2018).

DOI: 10.1103/PhysRevMaterials.2.044401

Comments

© 2018 American Physical Society. Used by permission.

Abstract

In an attempt to optimize leakage characteristics of α-Cr₂O₃ thin films, its dielectric properties were investigated at local and macroscopic scale. The films were grown on Pd(111), Pt(111), and V₂O₃ (0001), supported on Al₂O₃ substrate. The local conductivity was measured by conductive atomic force microscopy mapping of Cr₂O₃ surfaces, which revealed the nature of defects that formed conducting paths with the bottom Pd or Pt layer. A strong correlation was found between these electrical defects and the grain boundaries revealed in the corresponding topographic scans. In comparison, the Cr₂O₃ film on V₂O₃ exhibited no leakage paths at similar tip bias value. Electrical resistance measurements through e-beam patterned top electrodes confirmed the resistivity mismatch between the films grown on different electrodes. The x-ray analysis attributes this difference to the twin free Cr₂O₃ growth on V₂O₃ seeding.