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Photoluminescence ͑PL͒, radioluminescence ͑RL͒, and thermoluminescence ͑TL͒ investigation of Y 2 O 3 : Bi nanophosphors prepared by solution combustion synthesis using urea, glycine, and hexamethylenetetramine ͑HMT͒ as fuels was carried out. The as-prepared nanopowders have increasing crystallinity and average crystallite sizes for urea, glycine, and HMT, respectively. Luminescence is composed of two emission bands centered at 408 and 505 nm due to two nonequivalent Bi 3+ sites with symmetry S 6 and C 2 , respectively. The occupancy of these sites depends on the synthesis conditions, in agreement with theoretical predictions. Annealing at 1000°C for 1 h improves PL and RL efficiency due to enhanced crystallinity of the nanopowders and activation of recombination centers ͑Bi 3+ ions͒. No shift in the PL peak position was observed as a function of average crystallite size. The concentration quenching was experimentally determined to have a maximum emission of around 3 mol % of the dopant. TL spectra present several peaks between 50 and 300°C, and the total TL signal is correlated with the heat of combustion of the fuel and thus crystallinity increases. Most likely, increases in RL and TL are also due to the increase in the concentration of recombination centers.

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Fluorinated amorphous-carbon films (a-C:F:H) were deposited by low-power rf capacitively coupled plasma-enhanced chemical-vapor deposition using CH4–CF4 gas mixtures. Different series of films were deposited, changing one parameter at a time: the CF4 partial pressure from 0% to 100%, the self-bias voltage from −50 to −700 V, and the total deposition pressure from 5 to 15 Pa. The composition was determined by ion-beam analysis (IBA): Rutherford backscattering spectrometry, elastic recoil detection analysis, and nuclear reaction analysis. The atomic density of the films was evaluated by combining the IBA results with the thickness value measured by stylus profilometry. Film structure was investigated by infrared transmission and Raman scattering spectroscopies. The internal stress and Vickers hardness were also measured. For a fixed self-bias, the increase of the CF4 partial pressure leads to a higher fluorine incorporation and the decrease of both hardness and internal stress. The film microstructure changes from diamond-like to a polymer-like structure. The fluorine incorporation also increases with the self-bias, and fluorine-poor polymer-like films are deposited at low-bias voltage. Fluorine incorporation occurs at the expense of the hydrogen content in both cases, i.e., increasing the CF4 partial pressure or the self-bias. Finally, the role of ion bombardment during film growth on the mechanical and structure properties of the films is discussed.