Title: Probing carbon impurities in hexagonal boron nitride epilayers

Abstract

In this paper, carbon doped hexagonal boron nitride epilayers have been grown by metal organic chemical vapor deposition. Photocurrent excitation spectroscopy has been utilized to probe the energy levels associated with carbon impurities in hexagonal boron nitride (h-BN). The observed transition peaks in photocurrent excitation spectra correspond well to the energy positions of the bandgap, substitutional donors (C_B, carbon impurities occupying boron sites), and substitutional acceptors (C_N, carbon impurities occupying nitrogen sites). From the observed transition peak positions, the derived energy level of C_B donors in h-BN is E_D ~ 0.45 eV, which agrees well with the value deduced from the temperature dependent electrical resistivity. The present study further confirms that the room temperature bandgap of h-BN is about 6.42–6.45 eV, and the C_N deep acceptors have an energy level of about 2.2–2.3 eV. Finally, the results also infer that carbon doping introduces both shallow donors (C_B) and deep acceptors (C_N) via self-compensation, and the energy level of carbon donors appears to be too deep to enable carbon as a viable candidate as an n-type dopant in h-BN epilayers.

Authors:

Uddin, M. R.  ^[1];

• Search DOE PAGES for author "Uddin, M. R."
• Search DOE PAGES for ORCID "0000-0003-3679-196X"

Li, J.  ^[1];

• Search DOE PAGES for author "Li, J."
• Search DOE PAGES for ORCID "0000-0003-2880-7933"

Lin, J. Y.  ^[1];

• Search DOE PAGES for author "Lin, J. Y."
• Search DOE PAGES for ORCID "0000-0003-1705-2635"

Jiang, H. X.  ^[1]

• Search DOE PAGES for author "Jiang, H. X."
• Search DOE PAGES for ORCID "0000-0001-9892-4292"

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+ Show Author Affiliations

1. Texas Tech Univ., Lubbock, TX (United States). Dept. of Electrical and Computer Engineering

Publication Date:

Tue May 02 00:00:00 EDT 2017

Research Org.:

Texas Tech Univ., Lubbock, TX (United States)

Sponsoring Org.:

USDOE National Nuclear Security Administration (NNSA); US Army Research Office (ARO)

OSTI Identifier:

1466211

Alternate Identifier(s):

OSTI ID: 1361858

Grant/Contract Number:  

NA0002927; W911NF-16-1-0268

Resource Type:

Accepted Manuscript

Journal Name:

Applied Physics Letters

Additional Journal Information:

Journal Volume: 110; Journal Issue: 18; Journal ID: ISSN 0003-6951

Publisher:

American Institute of Physics (AIP)

Country of Publication:

United States

Language:

English

Subject:

36 MATERIALS SCIENCE; doping; materials properties; photonic bandgap materials; electrical resistivity; III-V semiconductors; carbon; photoelectric conversion; semiconductor growth; band gap; activation energies