Dual-wavelength photo-Hall effect spectroscopy of deep levels in high resistive CdZnTe with negative differential photoconductivity

0495542 - ÚFM 2019 RIV US eng J - Článek v odborném periodiku
Musiienko, A. - Grill, R. - Moravec, P. - Korcsmaros, G. - Rejhon, M. - Pekárek, J. - Elhadidy, Hassan - Šedivy, L. - Vasylchenko, I.
Dual-wavelength photo-Hall effect spectroscopy of deep levels in high resistive CdZnTe with negative differential photoconductivity.
Journal of Applied Physics. Roč. 123, č. 16 (2018), č. článku 161502. ISSN 0021-8979. E-ISSN 1089-7550
Institucionální podpora: RVO:68081723
Klíčová slova: semiinsulating cdte * semiconductors * signatures * detectors * mobility
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)
Impakt faktor: 2.328, rok: 2018

Photo-Hall effect spectroscopy was used in the study of deep levels in high resistive CdZnTe. The monochromator excitation in the photon energy range 0.65-1.77 eV was complemented by a laser diode high-intensity excitation at selected photon energies. A single sample characterized by multiple unusual features like negative differential photoconductivity and anomalous depression of electron mobility was chosen for the detailed study involving measurements at both the steady and dynamic regimes. We revealed that the Hall mobility and photoconductivity can be both enhanced and suppressed by an additional illumination at certain photon energies. The anomalous mobility decrease was explained by an excitation of the inhomogeneously distributed deep level at the energy Ev thorn 1.0 eV, thus enhancing potential non-uniformities. The appearance of negative differential photoconductivity was interpreted by an intensified electron occupancy of that level by a direct valence band-to-level excitation. Modified Shockley-Read-Hall theory was used for fitting experimental results by a model comprising five deep levels. Properties of the deep levels and their impact on the device performance were deduced. Published by AIP Publishing.
Trvalý link: http://hdl.handle.net/11104/0288502