Effect of heat treatment on the electrical properties of Mg-Zn-Fe-O system

Zinc substituted Mg ferrites with general formula Mg/sub 1-x/Zn/sub x/Fe/sub 2/O/sub 4/ (where x = 0.0, 0.25, 0.50, 0.75 and 1.0) prepared by the solid state reaction technique in single phase form. The d. c electrical resistivity measured by two probe method for each sample after successive heat treatments at 1000 degree centigrade, 1100 degree centigrade and 1250 degree centigrade has been observed to decrease with increasing quenching temperature, probably due to redistribution of cations on tetrahedral and octahedral sites. Temperature dependent electrical resistivity was measured after final heat treatment in the temperature range 20-200 degree centigrade reveals the semi-conducting nature of the samples. The activation varies in a manner similar to that of resistivity variation with the composition at room temperature. The drift mobility of the charge carriers was found to be in the range 10/sup -10/cm/sup 2/V/sup -1/s/sup-1/. (author)