Oxygen vacancies in monoclinic hafnia

ORAL

Abstract

Hafnia has recently received much attention because of its potential application as high-dielectric material replacing silica in microelectronic devices. Point defects -- in particular oxygen vacancies -- play an important role in this material as electron or hole traps. In this study, we perform electronic structure calculations on oxygen vacancies in hafnia using a combined Density functional Theory (DFT) and GW/BSE formalism. This formalism corrects for the error in calculating formation energy and charge transition levels using standard DFT. While there have been some GW studies on oxygen vacancies in hafnia using small supercells, we perform calculations using large supercells with 96 atoms. Such a large supercell calculation should minimize any spurious defect-defect interactions.

*This work was supported by National Science Foundation Grant No. DMR07-05941, the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 and DE-SC0001878. Computational resources have been provided by NSF through TeraGrid resources at TACC.

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Authors

  • Manish Jain

    • University of California, Berkeley, Lawrence Berkeley National Laboratory and University of Texas, Austin
    • UC Berkeley and Lawrence Berkeley National Lab

  • James Chelikowsky

    • University of Texas, Austin
    • University of Texas at Austin
    • The University of Texas at Austin
    • University of Texas

  • Steven G. Louie

    • UC Berkeley and Lawrence Berkeley National Laboratory
    • Department of Physics, University of California, Berkeley. Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California
    • University of California at Berkeley and Lawrence Berkeley National Lab
    • University of California at Berkeley and Lawrence Berkeley National Laboratory
    • University of California, Berkeley and Lawrence Berkeley National Laboratory
    • UC Berkeley
    • Department of Physics, University of California, Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory
    • UC Berkeley and Lawrence Berkeley National Lab
    • UC Berkeley and LBNL
    • Department of Physics, University of California, Berkeley, and Materials Science Division, Lawrence Berkeley National Laboratory
    • Dept. of Physics, University of California Berkeley and The Molecular Foundry, LBNL
    • Department of Physics, University of California at Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720