Abstract
A new surface-cleaning process for Si-MBE, termed Si-beam radiation cleaning (Rad clean), and a model of the cleaning process have been examined. Epitaxial Si layers of high quality have been obtained as a result of the formation of an inactive, very clean natual oxide, removal of this oxide together with contaminants slightly adsorbed on it, and dispersion of remaining contaminants without their developing into defect nuclei. Epitaxial Si layers with etch pit densities of less than 103/cm2 have reproducibly been obtained by carrying out growth at 500°C following the Rad clean process at 800°C for 2 min.