| Arrays of micro-bolometer are very promising as infrared detectors, since they do not require cryogenic cooling, thus allowing an effective cost reduction. The heart of a micro-bolometer is a thin-film layer, which is capable of changing its resistivity depending on the radiation absorbed. Boron-doped hydrogenated amorphous silicon (a-Si:H:B) has been recently introduced as potential resistive material, since it shows relatively high temperature coefficient of resistivity (TCR). The present research is focus on the optical (Raman, X-ray, absorption) and electrical (resistivity and TCR) characterization of a-Si:H:B thin films provided by Raytheon. Our results indicate that, in order to achieve higher values of TCR, the most promising deposition conditions are 245°C and 0.3 BCl3 relative gas concentration. The experiments also suggest that, by increasing the thickness of the amorphous layer, the short-range order of the structure could be improved. |
