Formation and electronic properties of erbium silicide on Si(100)

• Published in: Surface science 1994-04, Vol.307, p.258-263
• Main Authors: Kennou, S., Veuillen, J.Y., Tan, T.A.Nguyen
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Diffusion; interface formation; Electron and ion emission by liquids and solids; impact phenomena; Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems; Electron states and collective excitations in thin films, multilayers, quantum wells, mesoscopic and nanoscale systems; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Interfaces, heterostructures, nanostructures; Photoemission and photoelectron spectra; Physics; Solid surfaces and solid-solid interfaces; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/0039-6028(94)90404-9

The formation of erbium silicide ErSi 1.7 interface and thin films on plane and stepped Si(100) surfaces have been investigated by low-energy electron diffraction (LEED), photoelectron spectroscopy (XPS and UPS) and Auger electron spectroscopy (AES). For the interfaces, approximately 0.3–2 ML of Er was evaporated on the substrate and subsequently annealed at 400–600°C. For the thin films the co-evaporation method was used. On stepped Si(100) the surface state disappears less rapidly than on a plane one, suggesting a preferential clustering of the silicide along the steps. Upon annealing of the deposits (~ 50 to 100 Å) a diffuse (2 × 2) LEED pattern is observed at 600–800°C. This pattern corresponds to a (2 × 1)ErSi 1.7(10 1 ̄ 2) . The valence bands show two main peaks at 1.3 and 2.8 eV and no dispersion in the surface plane, confirming the poor crystallinity of the film. The results are discussed with those obtained for ErSi 1.7 Si(111) .