Surface core-level shifts in CdTe1-xSx(110) and CdTe1-xSex(110)

The metal chalcogenides CdTe1-xSx and CdTe1-xSex for x=0.05 have been studied with core-level spectroscopy. It was found that the surface core-level shifts of the Cd 4d and Te 4d spectra of these ternary compounds were quite small and similar to those of the binary compound CdTe. However, the S 2p and also the Se 3d spectra of the first surface layer showed much larger energy shifts toward lower binding energies than tellurium. The results are discussed in terms of initial- and final-state effects describing the x-ray photoemission process.