Parameter spaces for the nucleation and the subsequent growth of cubic boron nitride films

The data existing in the literature about the deposition of cubic boron nitride thin films were reviewed critically in order to establish the parameter spaces of c-BN nucleation and growth. The ion energy Ei, the flux ratio F (=incoming ions/incoming boron atoms), the ion mass mi, (or the ratio Ar/N2, respectively), and the substrate temperature Ts, had already been identified as the decisive parameters which are, however, interdependent. Earlier data collections on c-BN deposition had shown that, irrespective of the deposition technique used, a well-defined c-BN region exists in the F/Ei parameter space, in which the deposition of c-BN is possible. Similar regions exist in the F/mi and F/Ts parameter spaces. The present collection extends these older diagrams considerably, especially to the low energy region. From this extention it can be concluded that the momentum transfer concepts proposed in the literature fail to explain the data. Furthermore, the older collections were considered valid for nucleation and growth likewise. However, in recent years data have been published showing that the boundaries of the c-BN regions are different for nucleation and growth. After successful nucleation, subsequent growth can occur either at reduced ion bombardment (either energy or flux ratio or ion mass) and also at reduced temperatures. The existing data for this parameter reduction have been collected in this paper. It will be shown that the growth depends in a similar way as the nucleation on the (interdependent) ion bombardment parameters but no longer on temperature. This means that the nucleation and growth of c-BN are based on different, although in both cases ion-induced, mechanisms