| Summary: | 碩士 === 國立清華大學 === 化學工程學系 === 87 === Chemical Vapor Deposition(CVD) has wide applications in growing thin solid films and producing fine powders. The method is basically a synthesis of thin solid film or fine particles from gaseous reactants. In my thesis, the precursors are palladium acetate and silver acetate. I used the low pressure chemical vapor deposition to prepare the Pd-Ag alloy film.In my research, the composition of the alloy film is not affected by the way the two precursors are mixed, but is affected by the variation in flux of the carrier gas. Higher fluxes of carrier gas give alloy films of smaller grain sizes and smoother surfaces. Also, the alloy films are smoother when deposited at lower temperatures.The XRD patterns of palladium-silver alloy films reveal that the pure palladium and pure silver peaks are not present, and the diffraction peak is located between those of the pure palladium and pure silver. One can be sure that the peak is due to palladium-silver alloy. The average size of the alloy grains is determined by the X-ray line broadening technique (XLB) based on Scherrer's equation. The alloy grains have an average size between 20~50nm.From Auger/ESCA analysis, we found that the surface of the alloy films has higher silver content than the rest of the film.
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