Recovery Processes in Nickel Thin Films between 20 and 300°C

Evaporated nickel thin films about 500 Å thick are prepared by condensation at a rate of 5 Å/s onto glass substrates. Recovery processes are then studied by measuring the electrical resistance whilst the annealing temperature is increased linearly with time. This method gives the activation energy E and kinetic g of the recovery processes in individual samples. An investigation of the dependence of E on the pressure p during evaporation, controlled by emission of nitrogen gas, shows a reduction in E of about 1/4 as p is increased to around 10 −4 Torr. By extrapolation of E to p = 0 a value of E = (1.05 ± 0.07) eV is obtained. The annealing kinetic appears to follow g = 2. These values apply to the temperature region between 60 and 110°C. In the temperature range from about 230 to 270°C another recovery process is observed with an activation energy E of approximately 1.4 eV.