Nucleation of diamond on {111} surfaces of cubic boron nitride by CVD

Nucleation of diamond on hydrogenated {111} surfaces of c-BN cluster is investigated using the semiempirical molecular orbital method of AM I approximation. The heat of formation (HOF) at the first stage of growth has been calculated as a function of the charge given to clusters. The binding energies between gases (H, CH, CH2, CH3, C, and C-2) and c-BN have been calculated using the values of HOF and the important gases in the nucleation have been studied based on the nucleation theory. The CH and CH2 adsorbed on the {111} B surfaces exert positive influence on the nucleation by positive charges (+ 1 and +2), a pulsed positive charge (+ 1), and an alternating charge (+1 and -1) biased to the substrate. However, the abstractions of the H atoms from the {111}N surfaces are impeded because frontier orbitals of gases interact less effectively with frontier orbitals of the surface hydrogen atoms. (C) 2003 Elsevier B.V All rights reserved.