Characterization of Cd_(1-x)Fe_xS diluted magnetic semiconductors grown at near phase conversion temperature

摘要

Fe-based cadmium sulfide alloy thin films have been grown on c-plane sapphire substrates by a low-pressure metalorganic chemical vapor deposition technique at different growth temperatures. From X-ray diffraction and absorption spectra of the samples, the evolutions with growth temperature show an inflexion at the growth temperature of 300℃. This was attributed to the phase transformation from zinc-blende to wurtzite. With increasing growth temperature from 270℃ to 360℃, Fe concentration in the films increases monotonously. The electronic states of Cd_(1-x)Fe_xS were investigated by X-ray photoelectron spectroscopy. Magnetic measurement shows Van Vleck paramagnetism of the Cd_(1-x)Fe_xS thin film in the temperature region below 7 K.