The aim of this thesis is to develop high-performance materials for the next generation of microbolometers, with a particular focus on increasing the thermal resistance of the supporting arms to enable smaller pixel pitches. Our approach aims to take advantage of the lower thermal conductivity of materials induced by controlled inhomogeneities at the nanoscale. For this purpose, we have already demonstrated the fabrication of nanocrystallized amorphous silicon (nc-aSi) thin films (few tens of nanometers thick) with promising thermal conductivity.
In the case of nc-aSi, a range of characterization techniques—including Raman spectroscopy, X-ray diffraction, transmission electron microscopy (TEM), and the 3? method for thermal conductivity measurements—will be employed to correlate deposition conditions, nanostructure and thermal transport properties, in order to identify strategies for reducing its thermal conductivity.
The knowledge gained from studying nc-aSi could be extended to other materials.
Ideally, combining thermal measurement analysis with theoretical conduction models will provide insight into the mechanisms of heat propagation in these nanocrystallized materials.
Finally, the technological integration potential of these materials within the microbolometer fabrication line will be evaluated, including the mechanical strength and the thermal robustness.