ROLE OF ACCELERATED ELECTRONS IN DIAMOND FORMATION PROCESSES DURING ELECTRON-ASSISTED CHEMICAL-VAPOR-DEPOSITION

We have investigated diamond formation processes using electron impact in a Chemical vapor deposition reactor. In this technique, electrons emitted from a hot refractory filament are accelerated toward the substrate. The electron-related reactions occur mainly between the hot filament and the biased substrate. The deposition results demonstrated that electron impact has a significant effect upon the synthesis of diamond. The experimental results using mass spectroscopy suggested that accelerated electrons could dissociate H-2 under the low pressures required for diamond growth. An H-2 dissociation model for the diamond deposition process was described using a Monte Carlo computer simulation. Using this model, the energy of the accelerated electrons was calculated. The simulation demonstrated the presence of electrons which have kinetic energies higher than the energy required for H-2 dissociation. These results suggest that, the electron impact technique satisfies one of the crucial factors to form diamond, i.e. the generation of atomic H.