THE INFLUENCE OF DEPOSITION PARAMETERS ON THE LOW-TEMPERATURE RESISTIVITY OF ALPHA-MN THIN-FILMS

Resistivity measurements have been carried out on thin films of evaporated alpha-Mn between 300 and 1.5 K using the Van der Pauw technique. The resistivity results reveal a wide variety of low temperature behaviours ranging from that typical of bulk alpha-Mn to that regarded as typical of a metallic alloy glass with a negative temperature coefficient of resistivity at room temperature. This range of behaviours is influenced by substrate temperatures, deposition rates and ambient pressures increasing the excess low temperature resistivity as the perfection of the film decreases. The origin of this excess resistivity is associated with the effect of local disorder on the magnetic moment of the ions in the complex alpha-Mn structure.