Electrical conduction and electron emission of discontinuous thin films

The electrical conductivity of discontinuous thin metal films is assumed to be by a substrate-assisted tunnelling. Electrons travel from one island to another via impurity levels of the substrate surface. Electrons emitted into vacuum obey the Fowler-Nordheim equation for field emission. Field factors are calculated and related to the film structure. It is shown that electrons are emitted from small islands in the cathode region where the main voltage drop occurs.