CHARACTERIZATION OF CA1-XERXF2+X SOLID-SOLUTION THIN-FILMS GROWN ON SI(100) SUBSTRATES

Erbium-substituted Ca1-xErxF2+x calcium trifluoride layers were grown on Si(100) substrates by sublimation under ultrahigh vacuum of high purity solid solution powders. X-ray diffraction and scanning electron microscopy techniques were performed to study the texture and the structure of the layers. Their composition was mainly deduced from Rutherford backscattering of alpha particles and particle induced x-ray emission. For an erbium substitution rate, x, lower than 0.2, it has been shown that the film compositions are analogous with that of the sintered material and quite homogeneous. A Rutherford backscattering study in channeling conditions showed that heteroepitaxial Ca1-xErxF2+x/Si(100) structures c an be grown for a substrate temperature of 550-degrees-C.