STRUCTURAL-CHANGE AND HETEROEPITAXY INDUCED BY RAPID THERMAL ANNEALING OF CAF2 FILMS ON SI(111)

In this article we show that heteroepitaxial CaF2 films can be induced on Si(lll) with a rapid thermal anneal. The change from preferentiall y oriented polycrystals to a single crystal with type-B epitaxy is vis ible by different structural techniques. The x-ray photoelectron spect roscopy results indicate the presence of a reacted layer at the CaF2/S i interface with a pronounced increase of fluorine atoms at this inter face. Transmission electron microscopy results show that big structura l changes occur due to the thermal pulse. (C) 1998 American Vacuum Soc iety. [S0734-2101(98)07004-3].