Evaporant Sources for the Deposition of Pinhole-Free Films

Abstract

A new family of sources for vacuum evaporation has been developed for the deposition of pinhole-free films of insulators, semiconductors, and conductors. These sources make use of the fact that a flat plate will scatter particles of molecular size in all directions while reflecting macroscopic particles specularly. This directional separation makes it possible to divert the macroscopic particles away from the substrate. Homogeneous, pinhole-free films can be deposited with these sources at relatively high evaporation rates at close source-to-substrate distances. The use of these sources leads to reproducible films on a high yield basis. The same principle can be used in other applications requiring the filtering of vapors.