EVIDENCE FOR SURFACTANT-MEDIATED NUCLEATION AND GROWTH OF DIAMOND

Auger electron spectroscopy has been used as an in sial diagnostic in ultrahigh vacuum studies of diamond nucleation and growth on silicon. It is demonstrated that sp(3)-bonded carbon can be formed under ultrah igh vacuum conditions in the absence of excess hydrogen using a Aux of C2H4 molecules. For the conditions reported here, a silicon adlayer i s always present on the surface of the growing thin film. The presence of this adlayer suggests that the formation of sp(3)-bonded carbon oc curs by a surfactant mediated process. Specifically, silicon is though t to maintain the template for sp(3)-carbon growth by minimizing the s urface free energy for this structure. Further, the silicon adlayer is thought to enhance the growth kinetics of sp(3) carbon by providing a more reactive growth surface than a hydrogen-terminated carbon surfac e. (C) 1998 American Institute of Physics. [S0003-6951 (98)04928-6].