The electronic structure of the ion-beam-mixed Pt-Cu alloys by XPS and XANES

  • Lim, K.Y. (Department of Physics & Atomic-scale Surface Science Research Center Yonsei University) ;
  • Lee, Y.S. (Department of Physics & Atomic-scale Surface Science Research Center Yonsei University) ;
  • Chung, Y.D. (Department of Physics & Atomic-scale Surface Science Research Center Yonsei University) ;
  • Lee, K.M. (Department of Physics & Atomic-scale Surface Science Research Center Yonsei University) ;
  • Jeon, Y. (Department of Physics, Jeonju University) ;
  • Whang, C.N. (Department of Physics & Atomic-scale Surface Science Research Center Yonsei University)
  • Published : 1998.02.01

Abstract

In the thin film alloy formation of the transition metals ion-beam-mixing technique forms a metastable structure which cannot be found in the arc-melted metal alloys. Sppecifically it is well known that the studies about the electronic structure of ion-beam-mixed alloys pprovide the useful information in understanding the metastable structures in the metal alloy. We studied the electronic change in the ion-beam-mixed ppt-Ct alloys by XppS and XANES. These analysis tools pprovide us information about the charge transfer in the valence band of intermetallic bonding. The multi-layered films were depposited on the SiO2 substrate by the sequential electron beam evapporation at a ppressure of less than 5$\times$10-7 Torr. These compprise of 4 ppairs of ppt and Cu layers where thicknesses of each layer were varied in order to change the alloy compposition. Ion-beam-mixing pprocess was carried out with 80 keV Ae+ ions with a dose of $1.5\times$ 1016 Ar+/cm2 at room tempperature. The core and valence level energy shift in these system were investigated by x-ray pphotoelectron sppectroscoppy(XppS) pphotoelectrons were excited by monochromatized Al K a(1486.6 eV) The ppass energy of the hemisppherical analyzer was 23.5 eV. Core-level binding energies were calibrated with the Fermi level edge. ppt L3-edge and Cu K-edge XANES sppectra were measured with the flourescence mode detector at the 3C1 beam line of the ppLS (ppohang light source). By using the change of White line(WL) area of the each metal sites and the core level shift we can obtain the information about the electrons pparticippating in the intermetallic bonding of the ion-beam-mixed alloys.

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