Thermoelectric properties and mobility activation energy of amorphous As₂₀Se_80−xTl_x films

¹ Physics Department Faculty of Sciences South Valley University, 6 Kilo Road, 83523, Qena, Egypt
² Physics Department Faculty of Education Ain Shams University, Cairo, Egypt

Corresponding author: denglawey@lycos.com

Received: 7 March 2006
Revised: 9 December 2006
Accepted: 15 January 2007
Published online: 22 February 2007

Abstract

Thermal evaporation technique was used to prepare As₂₀Se_80−xTl_x films from bulk materials; ( at.%). The effect of TI addition on the thermoelectric properties and mobility activation energy of As-Se-Tl chalcogenide semiconductors has been studied in the homogeneous glass-forming region through temperature range (300–380 K). The thermoelectric power, TEP had a positive sign over the whole temperature range investigated, indicating p-type conductivity for As₂₀Se_80−xTl_x films. TEP activation energy, could be calculated from TEP measurements. It was found that decreases with increasing Tl-content and is found to vary between 0.814 and 0.517 eV. The mobility activation energy, could be calculated.