Characterization of Ca1−<i>x</i>Er<i>x</i>F2+<i>x</i> solid solution thin films grown on Si(100) substrates

Abstract

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 α 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 can be grown for a substrate temperature of 550 °C.