Effect of Sub-Micron Thin Film on Surface Temperature During Chemical Vapor Deposition

Abstract

In this paper, we investigated the effect of the film thickness on heat transfer and subsequent film temperature distribution of an optical fiber as it traverses through a chemical vapor deposition (CVD) reactor. A 50 nm thick carbon coating is applied on the optical fiber as it moves through the CVD reactor. In this process, the only heat source is the hot optical fiber entering the CVD reactor from the draw furnace. Radiation heat transfer from the optical fiber as it is being coated plays an important role during CVD carbon film growth. The carbon film will change the effective emissivity of the optical fiber as it traverses through the CVD reactor. This study will calculate the effective emissivity of this film-fiber structure based on wave theory, and evaluate the optical fiber’s resulting temperature field and rate of heat transfer loss during chemical vapor deposition. Results are correlated to operating conditions.