Growth Mechanism of Diamond Films

In the subsequent growth phase, the film accumulates further CH -units to keep expanding from the nucleus. It can grow laterally as well as vertically until a closed 

If some graphitic material should emerge nevertheless, it is selectively attacked by the hydrogen radicals and converted into hydrocarbons that return into the gas phase. Here they may be decomposed once more to give reactive species for further reaction. 

However, not only the choice but also the pretreatment of the substrate play an essential role for the nucleation rate and the quality of the diamond films obtained. Significantly better results are observed upon mechanically pretreating the surface. A polishing with diamond powder or with another abrasive, for instance, causes many scratches that then constitute preferred nucleation centers. Where diamond grinding powder is employed, the remnant tiny diamond fragments are assumed to serve to the same purpose. This effect can also intentionally be produced by depositing suitable centers of crystallization on the substrate. These include. 

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