This paper presents the results obtained for the extension to the thermal infrared of the Integrated Optics (IO) concept in preparation of ESA's space interferometer Darwin. This mission is devoted to the detection and characterization in the spectral range 6 - 20 m of earth-like planets orbiting solar-type stars. Since high dynamic range is required - typically 1:1e5 rejection ratio - wavefront modal filtering is mandatory. This cuold be achieved in the future with currently developed mid-infrared integrated optics. An IO component could also support various optical functions, and is thus likely to relax instrumental constraints. This paper addresses the manufacturing process and the characterization test results of newly developed IO device based on dielectric chalcogenide glasses and hollow metallic waveguides (HMW). In a first phase, the pre-selected technologies were validated and modal behaviour of the manufactured devices was demonstrated through polarization analysis. Preliminary nulling ratios higher than 1000 have been obtained with an IO modal filter at 10 microns. The methods used to validate the waveguide modal behaviour as well as implemented improvements are also discussed. After achieving 1:1e5 polychromatic extinctions with similar solutions in the near IR, the presented results further underline the credibility of a mid-infrared IO concept for Darwin.