Calcium tripolyphosphate films have been formed on steel electrodes by polarizing them slightly cathodically in a dilute aqueous solution containing Ca (NO3) 2 and Na5P3O10. When the solutions were adjusted to pH near the point where calcium tripolyphosphate was precipitated, they were supersaturated with calcium tripolyphosphate. Supersaturation was maintained during the film formation. It was found that the electrodeposition rate of calcium tripolyphosphate were determined by the degree of supersaturation and current density. The degree of supersaturation which depends on the concentration of the reagents, pH and the temperature, influence on the electrodeposition rate to a greater extent than current density. The film thus can be formed from dilute aqueous solutions and at the very low current density.
Transparent conductive F doped SnO2 films used for the electrode of amorphous Si solar cells were investigated in regard to their durability against hydrogen plasma. In general, both transparency and conductivity of SnO2 films are deteriorated with exposure to hydrogen plasma. However, it was found that the conductivity can be improved at the initial stage of the exposure mainly due to the change in electron mobility. The increase in mobility is explained in terms of reduction of the barrier potential due to termination of the dangling bonds with hydrogen atoms at the grain boundaries. The results obtained from SIMS, XPS, Auger microprobe analyses are described in detail.
Three background curves based on, (a) linear, (b) the Shirley's and (c) the Tougaard's methods were examined. The Tougaard method generates the best background curve, resulting in the nicely extracted XPS peaks.