SEMICONDUCTIVE PROPERTIES OF CU-CR FERRITES

Samples of type CuFe2-xCrxO4, where x = 0.0, 0.2, 0.4, 0.6, and 0.8, w ere prepared by the usual ceramic technique. The X-ray measurements co nfirmed that all samples were of spinel type of tetragonal crystal str ucture. The lattice parameter, density, theoretical density, and poros ity were determined at different Cr substitutions. Dc resistivity(rho) and thermoelectric power(alpha) were measured at temperatures differi ng from room temperature up to 580 K. The drift mobility mu(n) for n-c arriers within the sample was calculated at various temperatures. The results indicated that the samples have semiconducting behavior. At ro om temperature the majority carriers are electrons, except in case x = 0.8. The Curie temperature T-c shifts to higher temperature with incr easing Cr substitution. The drift mobility mu(n) increases exponential ly with temperature. The results are in good agreement with previous r esults.