Self-organized nanoscale structures in Si/Ge films

Nanotechnologies of the future will demand the creation of large arrays of nanoscale structures and morphologies for electronic and optoelectronic devices. One approach to the creation of such arrays is to ''let nature do it''. By depositing on each other semiconductor materials that differ slightly in lattice constant, one can use the resulting lattice strain to obtain arrays of three-dimensional crystallites or ''quantum dots''. Repealed deposition of alternate layers of one material and the other into a multilayer film enhances the regularity in position and size of these quantum dots, giving the prospect of a three-dimensional array of tiny structures that can communicate electronically but without wires. The concept is illustrated with experiments using SiGe films deposited on Si(001). (C) 1997 Elsevier Science B.V.