Preparation of Y3Al5O12:Eu3+ waveguide films by sol-gel method
A. García Murillo, F. de J. Carrillo Romo, C. Torres Orozco, M. García Hernández, E. Ramírez Meneses
CICATA - IPN UNIDAD ALTAMIRA, MX
Keywords: sol-gel, waveguides, europium, m-lines, yttrium aluminium garnet
Abstract:In this work, Y3Al5O12:Eu3+ (5 mol% Eu3+) optical thick films were obtained by sol-gel process. The films were dip-coated by dip-coating technique. The synthesis was accomplished using metal organic precursors, such as Al(tri-sec-butoxide) Al(OC4H9)3, yttrium chloride YCl3 6H2O, isopropanol and europium nitrate Eu(NO3)3•5H2O. The chelating agent was 2,4 pentanedione (CH3COCH2COCH3, acacH). After the precursor sol deposition stage, the YAG:Eu3+ films were dried and annealed at for 1 hour at 700 °C, 900 °C and 1100 °C. Multilayers were deposited to obtain multimode waveguides. The as-prepared thick films were structurally examined by XRD, AFM, SEM, HRTEM and m-lines spectroscopy. X-Ray diffraction analysis confirmed that Y3Al5O12:Eu3+ films presented the characteristic XRD pattern of YAG. Microscopic examination (HRTEM) of the films heat-treated at 1100 °C revealed that the YAG:Eu3+ films were constituted of particles with diameters of about 25 nm (Fig.1). The optogeometrical characteristics as thickness and refractive index were performed using the M-Lines Spectroscopy (MLS) using a He-Ne laser (632.8 nm). These results showed that the thickness and refractive index of the Y3Al5O12:Eu3+ film after a heating treatment at 1100 °C were 1.3 µm and 1.6385 respectively.