The variation of electrical conductivity with temperature for Cu-doped Zn-S alloy

Abstract

The variation of the electrical conductivity of copper (Cu) doped zinc sulphide (ZnS) alloy with temperature has been investigated. The electrical conductivity of the samples increases with temperature and obeys the Arrhenius relation, δ= δ_° exp (-E_g/2kT) which is characteristic of semiconductors. The energy gaps determined from this empirical relation are 3.91, 3.82, 3.74, 3.60 and 3.58 eV for the various samples. The result shows that the energy gaps of the samples decrease with increase in the incorporation of Cu in the intrinsic ZnS. The narrowing of the band gaps facilitates the ease of electronic transition from the valence band to the conduction band thereby enhancing the conductivity of the samples. All the samples investigated are characterized by wide band gaps which make them invaluable for the fabrication of optoelectronic devices that utilize wide band gap materials.


Keywords: electrical conductivity, temperature, zinc sulphide, copper, energy gap

Global Journal of Pure and Applied Sciences Vol. 11(4) 2005: 575-579