M. Abou Zied

Effects of copper content and heat treatment on the electrical properties of Ge15Te85-xCux thin films

Abstract The mechanism of incorporation of copper in amorphous films of Ge15Te85−x Cux (0≤x≤7 at.%) system and the effect of heat treatment are studied by measuring the dc conductivity in the temperature range (150–423 K). The results indicates that there are two conduction mechanisms. For temperature above 330 K, conductivity exhibits activated behaviour, while in low temperature range (T=150–300 K) conductivity exhibits non-activated behaviour. In the high temperature region, resistance and the activation energy have been calculated. The decrease in the activation energy on addition of Cu has been interpreted according to the Kastner model. In the low temperature region Motts parameters have been evaluated and they are decreased with Cu content; the results in this region are interpreted following Motts model.

Electronic Properties of Red P-Type Tl2S5 Single Crystals

Single crystals of red Tl2S5 were prepared by a special modified vertical Bridgman and Stockbarger technique. This growth was performed in our laboratory. The influences of temperature on the electrical conductivity, Hall mobility, carrier concentration, and thermoelectric power (TEP) were carried out in the temperature range 277–413 K. Throughout these measurements, various physical parameters such as effective mass of charge carriers, carrier mobility, diffusion coefficient, and the relaxation time for both majority and minority carriers were found.

Microstructure and Mechanical Properties of Nano-Crystalline Al-Mg-Mn System

Nano - crystalline Al-Mg-Mn was synthesized by ball milling technique. Microstructure of these alloys has been studied from X-ray line broadening. The crystallite size of nano - crystalline Al-Mg-Mn system decreases by increasing the Mg content, While the micro-strain, median diameter,, and geometrical standard deviations,  increases by increasing the Mg content. Micro-hardness of our system has been investigated by Vickers hardness test. The hardness increases by increasing the Mg content.