EXPERIMENTAL AND CALCULATIONAL STUDY ON DIAMOND GROWTH BY AN ADVANCED HOT FILAMENT CHEMICAL VAPOR-DEPOSITION METHOD

An advanced hot filament chemical vapor deposition (AHF-CVD), which enables independent control of CVD parameters, was performed to investigate the effect of each CVD parameter upon diamond growth. The simple configuration of this AHF-CVD system allows modeling as a one-dimensional plug flow reactor. Gas-phase chemical reactions were modeled by taking into account the temperature distribution between the filament and the substrate, to assess the role of such chemical species as hydrogen atom and methyl radical, in diamond growth. From a comparison between the experimental and calculated results, it was strongly suggested that the methyl radical is a promising diamond precursor in a system using CH4-H-2 as the source gas, and that a well-crystallized diamond would be deposited under the conditions of a large proportion of hydrogen atoms with respect to the precursor.