ELECTRICAL-RESISTIVITY OF AMORPHOUS ALLOY-FILMS - SNAU

Amorphous SnAu alloys are produced by quench condensation from the vapour phase on substrates held at 77K or lower temperature in ultra-high vacuum. It is shown that film thickness and thermal expansion of the substrate have only a minor influence upon the electrical resistivity, so that bulk properties of the amorphous state are measured. The electrical resistivity of amorphous SnAu has a negative temperature coefficient within the stability region from 15 to 80 at.% Au at temperatures higher than about 16K. With respect to concentration the electrical resistivity and the negative temperature coefficient show a maximum near 50 at.%. Compared with liquid SnAu the resistivity of amorphous SnAu alloys can be considered as the low-temperature limit of the hypothetical supercooled liquid. The transition temperature of superconductivity and the temperature of the amorphous-crystalline transformation are given.