Te-Ge-Se thermally co-evaporated films: Elaboration, characterization and use for the manufacture of IR rib waveguides, basic elements of CO2 microsensors

Films in a wide range of compositions in the Te-Ge-Se ternary system were prepared by thermal co-evaporation. The evolution of optical and thermal properties versus the composition has been used to determine an area of particularly interesting compositions for manufacturing waveguides being able to operate from 1 to about 17 µm. Rib waveguides based on these compositions were fabricated by using laser lithography and ion beam etching. Their optical losses were estimated to be 1.2 ± 0.6 dB·cm
⁻¹
at λ = 1.55 µm.