Effect of annealing on the resistivity of quench-condensed Cu and Cu(Fe) thin films

Abstract

Pure Cu and Cu(Fe) thin films containing ~0.1 and ~1.0 at % Fe were prepared by low-temperature deposition onto a liquid-helium-cooled substrate. The Cu (Fe ) films were annealed sequentially at approximately 17, 70, and 270 K. After each annealing stage the resistivity was measured down to ~l.5 K. The Cu(Fe) films exhibited a region in which the resistivity was proportional to In T; in this region the logarithmic slope of the resistivity curve was only weakly affected by annealing. Below ~ 10 K annealing produced a significant decrease in the impurity (Fe) contribution to the resistivity. The results are interpreted as due to increased interactions between Fe atoms produced by an increase in conduction-electron mean free path.