Low-Temperature Recovery of Resistivity in Electron-Irradiated Gold

This paper describes the results of two electron irradiations of 99.999% purity, 0.008-in. diam gold wire at 13° and at 10.5°K, respectively, and subsequent isochronal anneals. The anneals were carried out in 1- or 2-degree steps from the lowest temperature up to 65°K, and, in addition, the second set of anneals was extended for 1-hr periods at 125°, 170°, 225°, and 260°K. Each of the anneals produced some recovery. The plot of the slope of the isochronal recovery curve showed peaks and indicated a stage I in the annealing, extending up to 45°K, during which 28.5% of the resistivity increment annealed out. From 45° to 65°K (stage II) no distinct processes were observed. Stage II apparently continues up to 240°K; from 45° to 250°K, 36% of the resistivity increment anneals out; 35.5% remained at this temperature. By assigning a suitable frequency factor $K_0$ to each process in stage I, and assuming that the processes are first order (corresponding to recombination of close pairs of vacancies and interstitial), it is possible to calculate the activation energies for each process. For $K_0={10}^{10} \mathrm{to} {10}^{13}$ ${\sec }^{-1\mathrm{}}$, these ranged from 0.037 to 0.045 ev for the first peak to 0.11 to 0.13 ev for the fifth. An explanation is suggested for the major differences between the annealing behavior of gold and copper.