Process for Depositing Thin, Continuous Metal Films
Original Publication Date: 1983-Aug-01
Included in the Prior Art Database: 2005-Feb-07
During the initial growth of most metal films, the growth mechanism is such that the film first nucleates. As deposition continues, these nuclei grow in size to form islands. As the islands grow in size, they coalesce into a continuous film. For evaporated gold films the islands form a continuous film when the average thickness is about 7.5 nm. The thickness at which the film becomes continuous varies with the deposition conditions. Fig. 1 is a TEM micrograph of a typical gold film with an average thickness of 5.0 nm. The film shown in this figure has been evaporated onto an amorphous silicon nitride substrate. This micrograph shows the discontinuous nature almost always observed in gold films as thick as 7.5 nm. Most other metal films deposited onto ionic or covalent bonded substrates show similar structure.