Crystal growth by charged clsuter focused on CVD diamond process

摘要

Nucleation inthe solution or in the gas phase would be difficult to distinguish unless the nncelei grow into viscible size during crystal growth. The growth of nuclei tends to be suppressed when the nuclei are charged. Previosly, Glasner et al. made a systemaic study on crystal growh of KBr in the soluton by such block nuclei. Rectnly, we suggested a charged cluster model in the diamond CVD process, whose concept is very similar to that of Glasner et al. In he mode, chrged diamond cousters, which contain hundreds to thousands of atoms, are formed in the gas pahse in the diamond CVD diamond clusers, which contain hundreds to throusands of atoms, are formed in the gas pahse in the diamond CVD reactor and become the grwoth unit of diamond. The high capillary pressure built up inside the nanometer-size cluster increases the sability of diamond relative to that of grpahite. The presence of charge further stabilizes the dielekctric diamond over the conducitng grahite. The model can explain may unsuslaw phenomena taking palce in the diamond CVD process. Thepresence of the nanometer-sizxed charged carbon clusters wre confimred y Homann et al. in their cobmustion study of the C-H-O system under flame conditions where the diamond can be deposite. Crsytal growth by chrged clsuters is suggested to be the genral feature in the thin film process where an appreciable amoutn of chare is produced.