Current noise on Au thin films

The power spectrum of the current noise in Au thin films obtained by evaporation at a pressure of 10−6 Torr on amorphous quartz is given. The analysis frequency varies between 30 and 104 Hz. The experimental results refer to 35 films whose electrical resistance is between 30 Θ and 800 kΘ. The resistance temperature coefficient has either positive or negative values for different films. The power spectrum is measured for different values of temperature and electrical field applied to the films: the temperature is varied from 300 to 800 °K, and the electrical field from 0.1 to 30 V/cm. It is found that the power spectrum of the current noise is in all conditions of the type I/ƒα, whereα varies between 0.95 and 1.2. The noise intensity, which is different for different films, shows for all films a well marked maximum at about 500 °K and is proportional toI n (1.5≤n≤1.8), whereI is the current flowing through the film. Further experiments are presently carried out with different deposited metals and different support materials in order to verify whether the laws found generally apply to current noise in thin films.