MICROSCOPICAL STRUCTURING OF SOLIDS BY MOLECULAR-BEAM EPITAXY - SPATIALLY RESOLVED MATERIALS SYNTHESIS

The synthesis of microscopically structured solids by molecular beam epitaxy affords access to a new class of materials with accurately tailored electrical, optical, magnetic, dielectric, mechanical etc. properties. The semiconductor and metal superlattices described, which are made of alternating thin layers of two different materials, symbolize the beginning of a new area of materials engineering on a molecular (or atomic) scale. This periodic modulation of the chemical composition normal to the surface imposes an artifical periodicity on the semiconductor or metal crystal, a periodicity of one or two orders of magnitude larger than its natural lattice spacing.