Dependence of Oxygen Concentration and Temperature on the Growth Rate Distribution of SiO2 Solid Film by Chemical Vapor Deposition in the Hexamethyldisiloxane-oxygen System

In this paper, the growth rate distribution of SiO2 solid film by chemical vapor deposition (CVD) under a reduced pressure of 25,000 Pa has been investigated experimentally and numerically. The activation energy of the apparent surface reaction taking no particle formation into consideration was 335 kJ/mol. For all experimental conditions, the experimental results for the growth rate of CVD could be reproduced by the calculation ones before the maximum growth rate when mass transfer could be controlled by the apparent surface reaction. On the other hand, the calculation results for the growth rate of CVD disagreed to some extent with the experimental results after the maximum growth rate when mass transfer could be controlled by diffusion. By the observation of SEM images, the mass transfer in this CVD could include not only surface reaction but also particle formation. It was also suggested that the diffusion coefficient could become the apparent diffusion coefficient with the effect of particle formation. In future work, according to the estimation of the particle formation rate by using a membrane filter, the growth rate distribution could be reproduced by numerical calculation with not only surface reaction but also particle formation.