Surface Photovoltage Spectroscopy of Cd$\text{}_{0.97}$Fe$\text{}_{0.03}$Se and Cd$\text{}_{0.97}$Fe$\text{}_{0.03}$Te Crystals

The surface electronic structure of the Cd$\text{}_{1-x}$Fe$\text{}_{x}$Se and Cd$\text{}_{1-x}$Fe$\text{}_{x}$Τe crystals with x = 0 and x = 0.03 has been studied by Surface Photovoltage Spectroscopy (SPS). The change of surface photovoltage was observed due to photo-excitation of the electrons from the deep donor state Fe 3d to conduction band edge. This gave possibility to determine energy position of the Fe 3d state at 0.64 and 0.15 eV over the top of the valence band for CdSe and CdTe, respectively.