Bulk photovoltaic effect in carbon-doped gallium nitride revealed by anomalous surface photovoltage spectroscopy

I. Levine1, I. Gamov2, M. Rusu3, K. Irmscher2, C. Merschjann4, E. Richter5, M. Weyers5, and Th. Dittrich1

Published in:

Phys. Rev. B, vol. 101, no. 24, pp. 245205 (2020).

Copyright © 2020 American Physical Society. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the American Physical Society.

Abstract:

A bulk photovoltaic effect was observed in insulating carbon-doped gallium nitride crystals by investigating the light-induced change of the contact potential difference with a Kelvin probe as a function of the carbon concentration in the crystal. Bulk polarization was caused by excitation of defects setting in at photon energies of 0.95-1.05 eV (C1) and 2.5-2.6 eV (C3). From the dependence on the carbon concentration, C1 can be assigned to isolated carbon defects and C3 to tricarbon defects.

1 Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 12489 Berlin, Kekuléstrasse 5, Germany
2 Leibniz-Institut für Kristallzüchtung, 12489 Berlin, Max-Born-Strasse 2, Germany
3 Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Abteilung Struktur und Dynamik von Energiematerialien, 14109 Berlin, Hahn-Meitner-Platz 1, Germany
4 Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Institut für Angewandte Materialforschung, 14109 Berlin, Hahn-Meitner-Platz 1, Germany
5 Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, 12489 Berlin, Gustav-Kirchhoff-Strasse 4, Germany