Accession Number : ADA214348

Title :   Photoelectron Spectroscopic Study of the Interaction of Thin Fe Films with the MoS2(0001) Surface.

Descriptive Note : Technical rept.,

Corporate Author : AEROSPACE CORP EL SEGUNDO CA CHEMISTRY AND PHYSICS LAB

Personal Author(s) : Lince, J. R. ; Steward, T. B. ; Hills, M. M. ; Fleischauer, P. D.

Report Date : 01 NOV 1989

Pagination or Media Count : 34

Abstract : The Iron/Molybdenum Disulfide interface has been studied by high-resolution photoelectron spectroscopy using synchrotron radiation. The evolution of the MO 3d, Fe 3p, and S 2p core levels and of the valence band spectra (hv =152 eV) during growth of vapor-deposited Fe films (1-10) indicates the production of sulfur vacancy defects in the MoS2 (0001) surface. Several submonolayer sulfur surface species were formed, including sulfur adsorbed on the Fe surfaces and a reacted Fe-S species. The MoS2 surface was found to be covered for Fe film thicknesses of approx. 10A. Annealing a 10 film to 600 K resulted in the Fe film beginning to agglomerate, while annealing to 700 to 900 K resulted in further agglomeration of the Fe film. Annealing to 700 to 900 K also resulted in reformation of a partially disordered MoS2 (0001)-1 x 1 surface with approx. 5% defects, as determined from photoelectron spectroscopy and low-energy electron diffraction. The overlayer film remained primarily in the form of metallic Fe, before and after annealing to temperatures < or =900 K, which was shown by the behavior of the Fe3p core level spectra and valence band spectra. Annealing the sample to 1200 K resulted in decomposition of the MoS2 (0001) surface. The results indicate that the Fe/MoS2 (0001) system exhibits some interfacial reactivity but does not form bulk Fe-S compounds. The results have been compared to those of previous studies of the Fe/MoS2(0001) system. (AW)

Descriptors :   *THIN FILMS, *IRON, *MOLYBDENUM COMPOUNDS, *ELECTRON SPECTROSCOPY, *SULFIDES, *SURFACE REACTIONS, *CRYSTAL DEFECTS, ANNEALING, BAND SPECTRA, ELECTRON DIFFRACTION, GROWTH(GENERAL), HIGH RESOLUTION, INTERFACES, LOW ENERGY, PHOTOELECTRON SPECTRA, PHOTOELECTRONS, PRODUCTION, REACTIVITIES, SULFUR, SYNCHROTRON RADIATION, TEMPERATURE, THICKNESS, VALENCE BANDS, VAPOR DEPOSITION, ENERGY LEVELS, VACANCIES(CRYSTAL DEFECTS), ADSORPTION, AGGLOMERATES.

Subject Categories : Physical Chemistry
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE