Surface modification of field emission cathodes made of artificial carbon-based material.

While the field emission acts at the technical vacuum level conditions (10^-5 Pa) and electrons emitted from cathode, the ion bombardment exists and continuously modifies the cathode surface. Using X-ray photoelectron spectroscopy (XPS) we studied the electronic structure of thin surface layer of artificial carbon-based materials (ACB) used as field emission cathodes (FEC). The research resulted in the spectra of the samples B-1300, B-1500, B-1900. After spectra processing features analysis shows the change in type of hybridization of the original material. This change is supported by three characteristic spectral features: asymmetry of the core levels spectrum lines change, the satellite structure transformation, Auger-line and modification. So the initial material had sp² type of hybridization, the spectra show that in thin surface layer a new phase with sp³-hybridization exists and we can conclude formation of nanoclusters with diamond-phase in thin surface layer of cathode. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]