Two-photon excited LIF determination of H-atom concentrations near a heated filament in a low pressure H_2 environment

Abstract

With respect to the investigation of low pressure filament-assisted chemical vapor deposition processes for diamond formation, absolute concentrations of atomic hydrogen were determined by two-photon laserinduced fluorescence in the vicinity of a heated filament in an environment containing H(2) or mixtures of H(2)and CH(4). Radial H concentration profiles were obtained for different pressures and filament temperatures, diameters, and materials. The influence of the addition of various amounts of methane on the H atom concentrations was examined.