Abstract

Two-dimensional Laser Induced Fluorescence (2D-LIF) measurements are applied to the chemical vapour deposition (CVD) of diamond by an oxyacetylene flame. The fluorescence distributions of C₂, CH and OH are measured for various deposition conditions. The influence of the temperature of the molybdenum substrate and the distance between the substrate and the flame front on the two-dimensional distributions and on the quality and morphology of the deposited diamond is investigated. A clear relation is observed between the C₂ distribution in the flame and the local growth rate and quality of the diamond layer, therefore C₂ is thought to be an important species for diamond growth. Due to lower signal to noise ratios the role of CH as a growth species is less clear. The OH radical is not observed in the boundary layer, so OH seems to be of minor importance. All measurements are performed during diamond deposition.

© 1995 Optical Society of America