Insituelectrical resistivity measurement and structural analysis methods including MeV4He+ion backscattering, xhyphen;ray diffraction, Auger electron spectroscopy combined with Ar+sputtering, scanning and transmission electron microscopies have been used to investigate the properties and characteristics of the Tahyphen;Si thin alloy film system as a function of temperature. Stoichiometric TaSi2films were deposited by double electronhyphen;gun coevaporation on Si, oxidized Si, and sapphire substrates. A distinct drop in resistivity near 300thinsp;deg;C has been determined to be a transformation of the amorphous to crystalline phase. The kinetics of the transformation has been obtained by isothermal treatment over the temperature interval of 240ndash;280thinsp;deg;C. The results are interpreted in terms of a classical solidhyphen;state phase transformation model with at4(time) dependence and an apparent activation energy of 1.85 eV. Subsequent annealing causes further decrease of resistivity. The microstructures of films at various stages of annealing have been studied by xhyphen;ray diffraction and transmission electron microscopy. Correlation between the resistivity and microstructure is given and discussed.Insituresistivity of annealed films below room temperature has been measured. Crystalline TaSi2thin films do not become superconductive at 1.5thinsp;deg;K. Ionhyphen;beam mixed, coevaporated TaSi2film and films varying in composition from TaSi3.4to TaSi1.2prepared by cosputtering have also been studied. The results are compared and discussed.
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