Iron disilicide growth on Si(111): a scanning tunneling microscopy investigation

• Published in: Surface science 1993-03, Vol.284 (3), p.257-262
• Main Authors: Motta, N., Sgarlata, A., Gaggiotti, G., Patella, F., Balzarotti, A., De Crescenzi, M.
• Format: Article
• Language: English
• Subjects: Applied sciences; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Metals. Metallurgy; Physics; Solid surfaces and solid-solid interfaces; Surface and interface dynamics and vibrations; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/0039-6028(93)90496-7

The growth of Fe on Si(111)(7 × 7) has been studied by scanning tunneling microscopy as a function of the deposited thickness using both solid phase epitaxy and reactive deposition epitaxy. At submonolayer deposition of Fe and subsequent annealing at 600°C, flat islands of silicide with hexagonal symmetry become visible above the Si(7 × 7) reconstructed surface which supplies a bond length reference scale for the alloy. The islands tend to grow at the expense of the silicon substrate, creating a large number of surface steps. Atomically resolved images of the islands show that in all cases a cubic (2 × 2) phase is formed. The interplanar (111) distance is compatible more with the FeSi (CsCl structure) than with the FeSi 2 (CaF 2) epitaxy. The orthorhombic β phase does not form under the present growth conditions.