LEED-AES and XPS Studies of Bi-Sr-Ca-Cu-O Single Crystal Surfaces

Abstract

The well-defined clean surface in the 80K-phase Bi-Sr-Ca-Cu-O single crystal was obtained by cleaving it in air and heating it at 350°C in ultrahigh vacuum (UHV). The low-energy electron diffraction (LEED) pattern from the clean surface showed the perfect single domain of a 1×5 structure. From the Auger electron spectroscopy (AES) measurements, the cleaved surface might be a Bi-O layer and O atoms will be removed more easily than the other elements of Sr, Ca and Cu by Ar + sputter etching. In the clean surface of the single crystal, Cu 2+ was dominant. The X-ray photoelectron spectroscopy (XPS) spectrum of O 1 s consists of the O H (∼531 eV) and O L (∼529 eV) components, and the O H component is smaller than the O L component.