Polycrystalline Er-Sc silicates (ErxSc2-xSiO5 and ErxSc2-xSi2O7) were fabricated using multilayer nanostructured films of Er2O3/SiO2/Sc2O3 deposited on SiO2/Si substrates by RF-sputtering and thermal annealing at high temperature. RBS, TEM, GIXD, and PL results show the presence of ErxSc2-xSiO5 with an emission peak at 1528 nm for annealing from 900 to 1100 °C, and ErxSc2-xSi2O7 with an emission peak at 1537 nm for higher annealing temperature. The PL intensity of the ErxSc2-xSi2O7 phase is five times stronger than that of the ErxSc2-xSiO5 phase at 1250 °C. From PLE and PL spectra of ErxSc2-xSi2O7 thin film, we schematically illustrate the Er3+ Stark energy levels of 4I13/2 to 4I15/2 manifolds due to the crystal field strength effect of Sc3+. Temperature-dependent PL of the ErxSc2-xSi2O7 phase exhibits a variation of the full-width at half-maximum (FWHM) from 1.1 to 2.3 nm. The narrow FWHM is due to the small ionic radii of Sc3+, which enhance the crystal field strength affecting the optical properties of Er3+ ions located at the well-defined lattice sites of Sc silicate. A large excitation cross-section (δex) is equal to 3.0x10-20 cm2 at λex = 1527.6 nm.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics