Preparation and characterization of SiO2-ZrO2: Er3+/Yb3+ thin film deposited on fused silica and silicon wafer substrate via sol-gel dip coating technique

Rare earth (RE)–doped glass ceramics are promising materials for various photonics applications as the ions have photoluminescence properties from ultraviolet to near infra-red regions. In this paper, we present a report on SiO2− ZrO2:Er3+/Yb3+ planar waveguides, prepared using the sol-gel/dip coating technique. Thin films of 70SiO2 −30ZrO2 doped with three different ratios of Er3+/Yb3+ doping were fabricated on fused SiO2 glass and silicon (Si) wafer substrates. Optical and structural properties were obtained by prism coupler, atomic force microscopy (AFM), UV-VIS-NIR spectrophotometer, photoluminescence spectrophotometer and Raman spectrophotometer. Thin films coated on Si wafer showed positive effect on the film properties compared to the fused SiO2 substrate. The study showed that all samples emit red and green emission with the Si wafer coated film shows higher emission intensity and smoother surface morphology. The addition of high Er3+/Yb3+ doping increases the refractive index of the film which is beneficial for waveguiding properties. The Raman study showed that the substrates influenced the crystallinity of the films. Interaction between the RE ion doping and host material is critical in optimizing the performance of the devices.