Optical characterization of a-Si : H thin films grown by Hg-Photo-CVD

Mercury-Sensitized Photo-Assisted Chemical Vapor Deposition (Hg-Photo-CVD) technique opens new possibilities for reducing thin film growth temperature and producing novel semiconductor materials suitable for the future generation of high efficiency thin film solar cells onto low cost flexible plastic substrates. This paper provides some experimental data resulting from the optical characterization of hydrogenated amorphous silicon thin films grown by this deposition technique. Experiments have been performed on samples deposited at different temperatures, with and without thermal annealing.Mercury-Sensitized Photo-Assisted Chemical Vapor Deposition (Hg-Photo-CVD) technique opens new possibilities for reducing thin film growth temperature and producing novel semiconductor materials suitable for the future generation of high efficiency thin film solar cells onto low cost flexible plastic substrates. This paper provides some experimental data resulting from the optical characterization of hydrogenated amorphous silicon thin films grown by this deposition technique. Experiments have been performed on samples deposited at different temperatures, with and without thermal annealing

TIN OXIDE BLACK MOLYBDENUM PHOTOTHERMAL SOLAR-ENERGY CONVERTERS

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Magnetization of an electroless deposited nickel-phosphorus alloy

The influence of various annealings on the magnetization of a partially disordered Ni91P9 alloy has been investigated. The magnetic moment σ*o,o and the Curie temperature T c are found to vary linearly with the annealing temperature T a up to Ta = 523 K and the alloy behaves like a weak ferromagnet. With Ta > 573 K, the (200) reflexion of the f.c.c. nickel appears in the X-ray patterns and a sharp increase in T c and σ*o,o is observed. These results agree with previous thermomagnetic data which showed the alloy to be completely crystallized in a mixture of pure nickel and Ni3P alloy after heating to T a = 773 K. Anomalous thermal variation of the magnetization is observed below 50 K, as previously observed by other researchers.On étudie l'influence de différents recuits sur l'aimantation d'un alliage partiellement désordonné Ni91P9. Le moment magnétique σ *o,o et la température de Curie Tc varient linéairement avec la température de recuit, Ta, jusqu'à Ta = 523 K et le comportement reste celui d'un faible ferromagnétique. Lorsque Ta devient égale ou supérieure à 573 K, il apparait sur les diagrammes de rayons X la raie (200) du nickel c.f.c. et l'on observe une brusque augmentation de σ*o,o et de Tc. Ces résultats sont en accord avec une étude thermomagnétique ancienne qui montrait que cet alliage se transforme en un mélange cristallin de nickel pur et de phosphure de nickel Ni3P après un recuit à 773 K. Nous avons confirmé l'existence à basse température d'une anomalie dans la variation thermique de l'aimantation