Pedestal architecture to manufacture TeO2-ZnO waveguides for the development of photonic devices to operate in the infrared region

Abstract

The present work shows the feasibility of using the pedestal platform for the fabrication of TeO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> -ZnO waveguides and demonstrates the possibility of producing passive optical devices aiming the fabrication of optical amplifiers in the future for photonic applications in the infrared region. The pedestal structure is obtained by conventional photolithography and plasma etching and does not use metallic hard-masks that normally introduce roughness, leading to light scattering. This procedure, successfully used for GeO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> -PbO waveguides, benefits light guiding, as it reduces the propagation losses. Results of the procedure used for the TeO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> -ZnO pedestal waveguide fabrication are presented as well as propagation losses using the top view technique, at 632 and 980 nm. Scanning Electron Microscopy (SEM) was employed for the waveguides structure inspection. Near field mode profile results are also shown at 980 nm for waveguides width in the range of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$4-80\ \mu \mathrm{m}$</tex> and are compared with those obtained by numerical simulations. The fabrication process presented in this work opens possibilities for optical amplifiers fabrication with low propagation losses. Furthermore, this pedestal platform can be extended to different materials as well as other waveguide-based devices.