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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.

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Er3+, Nd3+ and Tm3+ doped Si/ZrO2 thin films have been prepared by rf co-sputtering. The films are 5 inches long and divided into 50 sections or positions, labeled from P1 to P50. The target configuration is such that the main target is ZrO2 (181.46 cm2), the rare earth (RE) oxide pellet (1.43 cm2) is placed on the main target below the middle of section of the film and the Si chip (6.67 cm2 or 6.00 cm2) is placed on the main target below one end of the film (P40 to P50). The films were annealed to 700°C. The Er3+4I13/2→4I15/2 emission was detected but no 4I13/2→4I15/2 emission was detected. The 4I13/2→4I15/2 emission shows a narrow peak at 1527 nm (FWHM = 6.5 nm for P20) with two weaker side bands from 1430 nm to 1500 nm and from 1550 nm to 1600 nm. The Nd3+4F3/2→4I9/2, 4F3/2→4I11/2, and 4F3/2→4I13/2 emissions were detected being the 4F3/2→4I11/2 peaked at 1065 nm (FWHM = 39.5 nm for P30) the strongest. The 4F3/2→4I9/2 emission is relatively weak, less than one-fourth the peak intensity of the 4F3/2→4I1/2 emission but is broad (FWHM = 92 nm for P30). No Er3+4I13/2→4I15/2 emission or Nd3+4F3/2 emissions were detected for the Si rich ends of the respective films, being the emission stronger from the Si poor end of the film towards the middle of the film. The maximum Er3+4I13/2→4I15/2 emission is for P20 and the maximum peak intensity for the Nd3+4F3/2→4I11/2 emission is for P30. The excitation wavelength dependence behavior for the Nd3+4F3/2→4I11/2 emission is that typical of energy transfer from the Si nanoparticles to the emitting Nd3+ ions. The excitation wavelength behavior for the Er3+4I13/2→4I13/2 emission reflects a mix of energy transfer from the Si nanoparticles and strong absorption for excitation wavelengths of 488.0 nm and 514.5 nm. The Tm3+ doped Si/ZrO2 thin film does not exhibit infrared (IR) PL from the 3H4 emission or the 3F4→3H6 emission. The intense band from 500 nm to 800 nm observed for all of the RE doped Si/ZrO2 films, due to defects in ZrO2, barely permits the detection of the Tm3+3H4→3H6 emission which is best observed for P35.