STUDIES ON COMPENSATED CU-CR-AL SPINEL OXIDE SEMICONDUCTORS

Electrical resistivity (rho) and thermoelectric power (alpha) measurem ents were carried out in air on CuCr2-xAlxO4(0.06 less than or equal t o x less than or equal to 0.10) spinel oxides in the temperature range 300-675 K. Carrier concentration (n), optical phonon frequency (gamma (o)), and mobility (mu)values have been calculated from resistivity an d thermoelectric power data. The results show that CuCr2-xAlxO4 spinel oxides are compensated semiconductors and the total compensation of t he hole carriers by electrons occur when 0.09 chromium ions are replac ed by aluminium ions. (C) 1995 Academic Press, Inc.