Analysis of a Thermal Plasma Diamond CVD System

Abstract

This paper deals with the analysis of a typical engineering system utilizing thermal plasma - a system for Diamond Chemical Vapor Deposition. It defines the system - a slightly overexpanded plasma jet impinging at a downstream -located substrate, outlines the theoretical description of the system - the Navier-Stokes and species conservation equations, and presents key theoretical results on the major and most troublesome factors influencing diamond deposition - velocity and temperature of the jet. Then, the paper demostrates the necessity to shift from a laminar to a turbulent flow description and compares both results to experiments. An explanation of the remaining discrepancy - insufficient velocity drop in the jet - is attempted.