Point defects and dopants of boron arsenide from first-principles calculations: Donor compensation and doping asymmetry

Journal Article · Mon Nov 19 00:00:00 EST 2018 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.5062267· OSTI ID:1543896

Chae, S. ^[1]; Mengle, K. ^[1]; Heron, J. T. ^[1]; Kioupakis, E. ^[1]

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1. Univ. of Michigan, Ann Arbor, MI (United States)

We apply hybrid density functional theory calculations to identify the formation energies and thermodynamic charge transition levels of native point defects, common impurities, and shallow dopants in B_As. We find that As_B antisites, boron-related defects such as V_B, B_As, and B_i-V_B complexes, and antisite pairs are the dominant intrinsic defects. Native B_As is expected to exhibit p-type conduction due to the acceptor-type characteristics of V_B and BAs. Among the common impurities we explored, we found that C substitutional defects and H interstitials have relatively low formation energies and are likely to contribute free holes. Interstitial hydrogen is surprisingly also found to be stable in the neutral charge state. Be_B, Si_As, and Ge_As are suggested to be excellent shallow acceptors with low ionization energy (<0.03 eV) and negligible compensation by other point defects considered here. Yet, donors such as Se_As, Te_As Si_B, and Ge_B have a relatively large ionization energy (~0.15 eV) and are likely to be passivated by native defects such as B_As and V_B, as well as C_As, H_i, and H_B. The hole and electron doping asymmetry originates from the heavy effective mass of the conduction band due to its boron orbital character, as well as from boron-related intrinsic defects that compensate donors.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). National Energy Research Scientific Computing Center (NERSC); Univ. of California, Oakland, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 1543896
• Journal Information: Applied Physics Letters, Vol. 113, Issue 21; ISSN 0003-6951
• Publisher: American Institute of Physics (AIP)
• Country of Publication: United States
• Language: English

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36 MATERIALS SCIENCE