Structural study of the epitaxial growth of fcc-Fe films, sandwiches, and superlattices on Cu(100)

The epitaxial growth of ultrathin films of pseudomorphic fcc-Fe on Cu(100) has been studied with several structure sensitive techniques. It has been found that the growth is not via a Frank-van der Merwe (layer-by-layer) mechanism, as proposed by several others, but exhibits Fe agglomeration, and at or slightly above 300 K, Cu surface segregation. This manner of growth is shown to be consistent with the generally recognized parameters which affect thin film growth. Several adsorbed gas species are found to affect strongly the growth process and the resulting film morphology. The conditions for growth of the best quality Fe films, sandwiches, and superlattices on Cu(100) are presented and are contrasted with the conditions which have been used in previous studies.