Frequency-dependent conductivity in unannealed thin films of As0.40Se0.40Te0.20


Bilen B., Skarlatos Y., Aktas G.

THIN SOLID FILMS, cilt.515, sa.13, ss.5329-5333, 2007 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 515 Sayı: 13
  • Basım Tarihi: 2007
  • Doi Numarası: 10.1016/j.tsf.2007.01.010
  • Dergi Adı: THIN SOLID FILMS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.5329-5333
  • Acıbadem Mehmet Ali Aydınlar Üniversitesi Adresli: Hayır

Özet

Direct current (d.c.) and alternating current (a.c.) conductivity measurements have been performed on unannealed amorphous As0.40Se0.40Te0.20 thin films. The d.c. measurements were performed at temperatures between 143 K and 343 K. The d.c. behaviour of the samples indicates different hopping conduction mechanisms between 143 K-210 K and 210 K-343 K. The a.c. measurements were performed at temperatures between 143 K and 300 K and at frequencies between 110 Hz and 1 MHz. The a.c. conductivity of the films is well represented by the form C omega(S) where C and s are found to be temperature dependent parameters. The data are found to fit the correlated barrier hopping model, especially at low temperatures. The comparison of a.c. data with the unified theory of the extended pair approximation shows that the results fit to the quasi universal law predicted by this model, however, qualitative calculations give unreasonable values for the decay parameter alpha and the exponent l. (c) 2007 Elsevier B.V. All rights reserved.