Sulfurization of InP(001) surfaces studied by X-ray photoelectron and X-ray induced Auger electron spectroscopies (XPS/XAES)

• Published in: Surface science 1995-07, Vol.331-333, p.434-440
• Main Authors: Chassé, T., Peisert, H., Streubel, P., Szargan, R.
• Format: Article
• Language: English
• Subjects: Auger electron spectroscopy; Chalcogens; Clean metal, semiconductor, and insulator surfaces; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron and ion emission by liquids and solids; impact phenomena; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Indium phosphide; Photoemission and photoelectron spectra; Physics; Surface and interface electron states; Surface electronic phenomena; Surface states, band structure, electron density of states; Thermal desorption; X-ray photoelectron spectroscopy
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/0039-6028(95)00306-1

Surface chemistry of n- and p-doped InP(001) after treatment with sulfur from different sources has been investigated by XPS/XAES measurements. Core level lines, valence band spectra and Auger transitions were related to changes in surface chemistry and band bending. Both high resolution chemical shifts and the Auger parameter concept were used for the identification of chemical species. Sulfurization was performed by dipping the chemically cleaned sample into a (NH4)2S solution or by exposing it to S2 or H2S molecules in UHV. Depending on the source and on the annealing temperature several sulfur compounds were observed on the surface and identified as sulfides with sulfur substituting phosphorus or with sulfur as surface atom, and as polysulfide probably with one sulfur atom in a terminal position. Changes of surface Fermi energy position and thus band bending were investigated.