Structure and electrical conduction of discontinuous gold films evaporated in vacuum on carbon and silicon monoxide substrates

Abstract

Abstract Experimental results concerning the structure and d.c. electrical conductance of discontinuous gold films evaporated in vacuum (1×10-7 Torr) on amorphous carbon and SiO substrates are reported. It is shown that the distribution of gold islands can be described by a log-normal distribution with d =10–73 nm and σ=1.22–1.59. For the “maze” structure the “break-up” effect was observed at about 360 K for Au/C films and at about 320 K for Au/SiO films. We observed a high threshold (about 0.85) of metal surface coverage to be necessary for the transition from activated to metallic conduction in the film. A discussion of the observed effects and of discrepancies between experimental data and relevant current theories is given.