Abstract

We report on a new method to improve the deposition rate of the MCVD process. Where the inside deposition thermophoresis is regarded as the particle transport mechanism,¹ measures taken to raise the gradient of the radial temperature distribution result in an increase of the deposition efficiency. So far, the following have been tested: (1) cooling the substrate tube downstream from the reaction zone²; (2) plasma heating within the tube³; and (3) deposition from an annulus with heated central rod.⁴

© 1985 Optical Society of America