Semiconductive properties of CuCr ferrites

Abstract Samples of type CuFe 2- x Cr x O 4 , where x = 0.0, 0.2, 0.4, 0.6, and 0.8, were prepared by the usual ceramic technique. The X-ray measurements confirmed that all samples were of spinel type of tetragonal crystal structure. The lattice parameter, density, theoretical density, and porosity were determined at different Cr substitutions. Dc resistivity (ρ) and thermoelectric power (α) were measured at temperatures differing from room temperature up to 580 K. The drift mobility μ n for n-carriers within the sample was calculated at various temperatures. The results indicated that the samples have semiconducting behavior. At room temperature the majority carriers are electrons, except in case x = 0.8. The Curie temperature T c shifts to higher temperature with increasing Cr substitution. The drift mobility μ n increases exponentially with temperature. The results are in good agreement with previous results.