Epitaxial films

Abstract

The chemical solution deposition (CSD) method involves the synthesis of films with a mixture of precursor molecules, dissolved in a common solvent, and uniformly spread on a substrate. When applied to single crystal substrates, sequential events occur during heating that can produce a single crystal, epitaxial film. Upon heating, precursor film decomposes (pyrolysis) to form an inorganic, amorphous phase that crystallizes at a higher temperature, forming a single crystal film at higher temperatures. The fundamentals of CSD will be reviewed to include the relation between cracking and film thickness-one limitation of CSD, why a polycrystalline film with nano grain size is formed before being converted into a single crystal, the crystallization of metastable phases, mechanisms that convert the polycrystalline film into a single crystal film, how polycrystalline films can break into isolated islands with a specific crystallographic orientation that can be used to 'seed' a single crystalline film, and why dissimilar crystal structures epitaxially grow on one another.