Thin film and surface alloy formation with Cu deposits on Pt(100)hex

• Published in: Surface science Vol. 357; pp. 943 - 948
• Main Authors: Radnik, J., Wagner, B.D., Oster, K., Wandelt, K.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 20.06.1996
• Subjects: Alloy; Auger electron spectroscopy; Copper; Low energy electron diffraction; Metallic films; Platinum; Surface reconstruction; Ultraviolet photoelectron spectroscopy; Xenon; Surface reconstruction; Platinum; Xenon; Metallic films; Auger electron spectroscopy; Copper; Alloy; Ultraviolet photoelectron spectroscopy; Low energy electron diffraction
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/0039-6028(96)00296-8

The properties of ultrathin Cu films on Pt(100)hex and their thermally activated transformation into CuPt surface alloys are investigated by AES, LEED and PAX. Cu deposition at room temperature leads to a local lifting of the hexagonal Pt surface reconstruction which is completed by one pseudomorphic Cu monolayer. Below 550 K the Cu then continues to grow with its own Cu(100) lattice parameter. With increasing temperature different metastable ordered CuPt surface alloys could be prepared due to the interdiffusion of the components. Between 550 and 650 K a c(2 × 2) superstructure is observed, while between 650 and 750 K a phase transition to a p(2 × 2) or a (2 × 1) is detected. PAX measurements reveal unambiguously a pure Cu termination of both surface alloy phases. Above 950 K the Cu disappears into the bulk leaving a clean Pt(100)hex surface behind.