Structure of epitaxial gadolinium silicide thin films obtained by Gd evaporation and by Gd and Si coevaporation on Si(111)

• Published in: Solid state communications 1995-06, Vol.94 (10), p.837-841
• Main Authors: Pescher, C., Ermolieff, A., Veuillen, J.Y., Nguyen Tan, T., Brunel, M.
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Physics; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/0038-1098(95)00138-7

Silicide thin films were epitaxially grown by Gd evaporation and by Si and Gd co-evaporation for 45 minutes on a Si (111) wafer. After annealing at three different temperatures 400°C, 450°C, and 740°C for 15 minutes, these samples were analysed by Ultra Violet Electron Spectroscopy (UPS), X Ray Electron Spectroscopy (XPS), Secondary lon Mass Spectroscopy (SIMS), Low Energy Electron Diffraction (LEED), and Grazing Incident X Ray Diffraction (GIXRD). It was concluded that the silicide thin films obtained, approximatively 12 nm thick, verify a chemical formula Gd 3Si 5 with “free” or cluster forming silicon embedded in films in concentrations which could be as high as 30%. Cristallographic structure is an hexagonal AlB 2 type one for samples annealed at temperatures higher than 400°C.