Hopping conduction in Ga4Se3S layered single crystals


QASRAWI A. F. H., Gasanly N.

SOLID STATE COMMUNICATIONS, cilt.148, ss.190-193, 2008 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 148
  • Basım Tarihi: 2008
  • Doi Numarası: 10.1016/j.ssc.2008.08.021
  • Dergi Adı: SOLID STATE COMMUNICATIONS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.190-193
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

The conduction mechanism in Ga4Se3S single crystals has been investigated by means of dark and illuminated conductivity measurements for the first time. The temperature-dependent electrical conductivity analysis in the region of 100-350 K, revealed the dominance of the thermionic emission and the thermally assisted variable range hopping (VRH) of charged carriers above and below 170 K, respectively. The density of states near the Fermi level and the average hopping distance for this crystal in the dark were found to be 7.20 x 10(15) cm(-3) eV(-1) and 7.56 x 10(-6) cm, respectively. When the sample was illuminated, the Mott's VRH parameters are altered, particularly, the average hopping distance and the density of states near the Fermi level increase when light intensity increases. This action is attributed to the electron generation by photon absorption, which in turn leads to the Fermi level shift and/or trap density reduction by electron-hole recombination. (C) 2008 Elsevier Ltd. All rights reserved.