Atomic layer deposition of ytterbium oxide using β-diketonate and ozone precursors

Yb2O3 thin films were grown onto Si(1 0 0) and glass substrates by atomic layer deposition using Yb(thd)3 and ozone precursors. Self saturating growth appeared when the growth temperature was between 300 and 350 °C. Polycrystalline BCC structure with (2 2 2), (4 0 0), (4 1 1), (4 4 0), (6 1 1) and (6 2 2) orientations was observed using X-ray diffraction measurements with lattice constant a0=10.4 Å. The mass density for the films grown at 300 and 350 ° C was found to be 8.9 and 9.0 g/cm3, respectively. The film roughness increased with growth temperature from 0.9 (at 300 °C) to 1.3 nm (350 °C). Elastic recoil detection analysis revealed that the Yb/O ratio of the films grown at 350 ° C was 0.63 and the films contained 1.1% hydrogen, 0.7% carbon and 0.08% nitrogen impurities. The refractive index of the film was about 1.9 at near-IR wavelength.