Berlin 2012 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 31: Clean surfaces II
O 31.1: Talk
Tuesday, March 27, 2012, 10:30–10:45, A 060
Characterisation of a ceria film on Si(111) with non-contact atomic force microscopy — •Reinhard Olbrich1, Hans Hermann Piper1, Marvin Zoellner2, Thomas Schroeder2, and Michael Reichling1 — 1Universität Osnabrück, Germany — 2IHP Frankfurt (Oder), Germany
A 180nm thick film of ceria deposited on Si(111) is studied with atomic force microscopy operated in the non-contact mode (NC-AFM) and Kelvin probe force microscopy (KPFM). The thin film is prepared by annealing to different temperatures in an ultra-high vacuum environment. Up to a temperature of 845 K, pyramidal triangular structures are observed. In a temperature range from 515 K to 780 K, 6 to12 nm high spikes appear between the triangle structures. After annealing the film to 930 K and higher temperatures flat terraces and step structures develop on the film surface that are similar to structures observed on CeO2 (111) surfaces of bulk crystals. Annealing temperatures over 1130 K causes a decomposing of the thin film. Sputtering the ceria film and anealing at 1110 K generates the best results whith clear terraces and step structures. The KPFM measurement reveals a positive local charge at step edges and a lower charge on the terraces.