Fabrication and characterization of pedestal optical waveguides using TeO2–WO3–Bi2O3 thin film as core layer

• Waveguides were produced using a novel material, the TeO2–Bi2O3–WO3 thin films.
• A non-conventional method of waveguide production was presented.
• Propagation losses at 633 nm presented better results than 1050 nm.
• Multimode behavior was observed in waveguides with width larger than 9 μm.
• Passive characterizations in the Mach–Zehnder structures were performed.

We present the production and characterization of pedestal type optical waveguides with TeO2–WO3–Bi2O3 thin films to be used as core layer for applications in optical devices such as the Mach–Zehnder Interferometer (MZI). The optical waveguides and MZI structure were fabricated from pedestal type obtained using conventional optical lithography procedures, followed by plasma etching and Magnetron Sputtering deposition. Optical measurements were performed to characterize the waveguides and MZI. Propagation losses around 2.0 dB/cm and 2.5 dB/cm were obtained at 633 and 1050 nm respectively. Single-mode propagation at 633 nm wavelength was observed for waveguide width up to 5 μm; larger waveguide width provided multi-mode propagation. Also, preliminary characterizations of the pedestal MZI structure presented multi-mode propagation for waveguide width of 30 μm.