Ferromagnetism in Zn1-xCrxTe (x=0.05, 0.15) films grown on GaAs(100) substrate

Zn1-xCrxTe (x = 0.05, 0.15) films were grown on GaAs(1 0 0) substrate by thermal evaporation method. X-ray diffraction analysis showed the presence of ZnCrTe phase without any secondary phase. The surface was analyzed by high resolution magnetic force microscope and profile measurements showed orientation of magnetic domains in the range of 0.5-2 nm with increase of Cr content. Magnetic moment-magnetic field measurements showed a characteristic hysteresis loop even at room temperature. The Curie temperature was estimated to be greater than 300 K. From the electron spin resonance spectra, the valence state of Cr in ZnTe was found to be +2 with d(2) electronic configuration. Hall effect study was done at room temperature and the result showed the presence of p-type charge carriers and hole concentration was found to increase from 5.95 x 10(12) to 6.7 x 10(12) m(-3) when Cr content increases. We deduce the origin of ferromagnetic behavior based on the observed experimental results. (c) 2009 Elsevier B.V. All rights reserved.