Regensburg 2002 – wissenschaftliches Programm
O 33.8: Vortrag
Donnerstag, 14. März 2002, 17:15–17:30, H44
The Growth of ultrathin Fe films on well ordered β−Ga2O3/CoGa(100) — •Feng-Ming Pan, Domokos Kovács, Rudolf David, Laurens Verheij, and René Franchy — Institut für Schichten und Grenzflächen, ISG3, Forschungszentrum Jülich, D-52425 Jülich, Germany
The growth and structure of Fe thin films on β−Ga2O3/CoGa(100) was studied by means of thermal energy He atom scattering (TEAS), low energy electron diffraction (LEED), and Auger electron spectroscopy (AES). An ultrathin β−Ga2O3 film was prepared on CoGa(100) by oxidizing the surface at 800 K. The β−Ga2O3 film grows in two domains which are perpendicular to each other, with a (2×1) structure with respect to the CoGa(100) surface. At 300 K, Fe grows on β−Ga2O3 with a (1×1) structure which corresponds to bcc α-Fe. The Fe film grows with the (100) plane parallel to the CoGa(100) surface. Upon annealing the Fe films prepared at room temerature, both the sharpness and the intensity of the helium diffraction peaks of the (1×1) structure of Fe are enhanced significantly, implying a surface with higher order. No layer by layer growth mode is found for the Fe on β−Ga2O3/CoGa(100) surface in the temperature range between 110 K to 600 K, which can be understood in terms of the surface free energy. The Fe film is stable on the β−Ga2O3/CoGa(100) surface up to 600 K. At higher temperatures the amount of Fe decreases, but some of the Fe remains visible even at very high temperature (1100 K).