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A few monolayers of Gd atoms were evaporated on a clean CdTe(p)(100) (bulk crystal) and CdTe(n)(100) (epitaxial layer) surface. Constant initial state (CIS) spectra were measured at the Gd4d → Gd4f Fano resonance (in the photon energy range of 140–160 eV) both after evaporation and heating processes. The binding energy of the Gd4f state was determined after Gd evaporation (9.43 and 9.50 eV for p- and n-type crystals, respectively) and after heating (9.00 and 9.80 eV). Energy distribution curves (EDCs) measured in the photon energy range (50–100 eV) show additional density of states at the valence band edge only for CdTe(n)/Gd crystal.

The electronic structure of Cd 0.985 Fe 0.015 Te has been studied by resonant photoemission in the synchrotron radiation photon energy range from 48 to 67 eV. Photoemission spectra revealed that Fe contributions to the valence band density of states are situated at 1.2 eV, 4.1 eV and 5.9 eV below the valence band maximum. The contribution of Fe 3d states to the valence band electronic structure was also observed in situ during evaporation of Fe atoms on the clean CdTe(110) surface. Photoemission measurements show that after Fe evaporation and heating to 265°C the CdTe(110)/Fe crystal, a ternary compound Cd 1− x Fe x Te is created in the surface region. The results of photoemission experiments are consistent with the theoretical calculations made by the CPA (coherent potential approximation) method.