Estimation the Density of Localized State Glassy Se_100–xZn_x Thin Films by Using Space Charge Limited Conduction Measurement

Mohd. Nasir, M. Zulfequar

Department of Physics, Jamia Millia Islamia, New Delhi, India.
Department of Physics, Jamia Millia Islamia, New Delhi, India..

DOI: 10.4236/njgc.2012.22013                

Abstract

The dc conductivity in vacuum evaporated amorphous thin films of the glassy alloys Se_100–xZn_x(2 ≤ x ≤ 20) are meas-ured in the temperature range (308 - 388 K). The dc conductivity (σ_dc) is increases with increased of Zn concentration in the glassy alloys. The activation energy (ΔE) decreases with increase of Zn content. The conduction is explained on the basis of localized state in the mobility gap. To study the effect of electric field, a Current-Voltage characteristic has been measured at various fixed temperatures. The Current-Voltage data are fitted into the theory of space charge limited conduction in case of uniform distribution of traps in mobility gap at high electric fields (E ~10⁴ V/cm) of these materials. The density of localized state (g₀) are estimated by fitting in theory of space charge limited conduction (SCLC) at the temperature range of (352 - 372 K) in the glassy Se_100–xZn_x. The density of localized state (₀) near the Fermi level are increases with increase of Zn concentration in the (Se_100–xZn_x) thin films and explain on the basis of increase of the Zn-Se bond.

Keywords

Density of Localized State; dc Conductivity; Activation Energy (?E); SEM; Thin Films

Conflicts of Interest

The authors declare no conflicts of interest.

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