Observation of Meyer-Neldel rule in amorphous films of Ge_1–xSe₂Pb_x

¹ Physics Department, Faculty of Education, Ain Shams University, Cairo, Egypt
² Physics Department, Faculty of Science, Suez Canal University, Port-Said, Egypt
³ Department of Physics & Mathematical Engineering, Faculty of Engineering, Suez Canal University, Port-Said, Egypt

Corresponding author: prof_nahhas@yahoo.com

Received: 26 May 2008
Accepted: 6 October 2008
Published online: 14 January 2009

Abstract

Electrical conductivity was performed on amorphous thin films of Ge_1–xSe₂Pb_x (with x = 0, 0.2, 0.4, 0.6 and 0.8) as a function of temperature in the range 300–450 K. The experimental results indicate that the conduction is through thermally activated process having two conduction mechanisms. In the first region at high-temperatures range, the values of suggest that the dominant conduction of charge carriers changes from the extended states to the localized states in the band tails at composition x = 0.8. The experimental results have also been analyzed using Meyer-Neldel Rule. The other one appears in the low temperatures region and the conductivity has been analyzed using Mott's variable range hopping conduction. Mott's parameters were calculated for Ge_1–xSe₂Pb_x films.