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Er-, Nd- and Tm-doped Si-yttria stabilized zirconia (YSZ) thin film samples were prepared by rf co-sputtering. Chemical composition of the samples was determined using energy-dispersive spectroscopy (EDS) and the structure of the films by x-ray diffraction (XRD). The samples were annealed to 700 °C. Photoluminescence (PL) measurements were performed for the visible and infrared. Excitation with 457.9 nm produces spectra in the visible range due mostly to defects in the YSZ matrix with a weak Si nanoparticle surface state emission; the Tm-doped samples also present emission. Excitation with 488 nm produces spectra in the visible range with additional rare earth emissions such as the and emissions for the Er-doped samples and the emissions for the Nd-doped samples. The Er-doped samples present weak emissions and narrow emissions in the infrared range, while the Nd-doped samples present and emissions. No Tm3+ emissions in the infrared were observed. Excitation wavelength dependence measurements for the emissions show that these are due to energy transfer from the defects in the YSZ as well as from the Si nanoparticles while the same measurements for the emissions show that these are due to energy transfer from the Si nanoparticles only. Excitation flux dependence measurements for the and emissions show the sub-linear dependence characteristic of rare earth ion excitation through energy transfer from Si nanoparticles. emission dependence on emission showed that the former was possibly due to a combination of downconversion from higher levels of the Er ions, energy transfer from Si nanoparticles and upconversion transfer processes. We concluded that Er-, Nd- and Tm-doped Si-YSZ are promising materials for photonic applications, being easily broadband excited using low pumping powers.

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Si/SiO2, RE2O3/Si/SiO2 and RE2O3/Si/Al2O3 films were sputtered. Si/SiO2 films were annealed to 1100°C for 30 min in Ar. RE2O3/Si/SiO2 films were annealed to 700°C, 1000°C, or 1100°C for 30 min in Ar. RE2O3/Si/Al2O3 films were annealed to 700°C for 30 min in Ar. Raman spectra and photoluminescence (PL) obtained for the Si/SiO2 films show relation between Si nanocrystal (nc) presence, Si nanoparticle (np) PL and Si target area. Nd2O3 co-sputtered films presented PL for the (4F5/2, 2H9/2) → 4I9/2, 4F3/2 → 4I9/2, 4F3/2 → 4I11/2, and 4F3/2 → 4I13/2 transitions. Er2O3 co-sputtered films presented PL for the 4I11/2 → 4I15/2, and 4I13/2 → 4I15/2 transitions. Tm2O3 co-sputtered films presented PL for the 3H4 → 3H6 transition. Different spectral shapes were observed for the infrared (IR) PL of the Er3+ ions and of the Nd3+ ions for the RE2O3/Si/Al2O3 films with respect to the RE2O3/Si/SiO2 films.

Si-rich SiO 2 , Nd-doped Si-rich SiO 2 and Nd-doped SiO 2 thin films were prepared. Photoluminescence (PL) spectra for visible and infrared were obtained for each as-deposited film. The samples were annealed by steps to different temperatures within the range 600°C-1100°C for 30 minutes at each annealing temperature. PL spectra were obtained at each step and their characteristics were studied. The best annealing temperature for the PL of the rare earth (RE) ions was obtained. The PL spectra of the films were compared with one another. Energy transfer from the silicon nanocrystals (Si nc) to the RE ions is verified using excitation wavelength and excitation power spectra.