A Mathematical Model of the Coupled Fluid Mechanics and Chemical Kinetics in a Chemical Vapor Deposition Reactor

TLDR

The study presents a numerical model coupling gas‑phase hydrodynamics and chemical kinetics for silicon CVD. The model incorporates a 20‑step silane decomposition mechanism and solves for temperature, velocity, species concentrations, and silicon deposition rates as functions of susceptor temperature, carrier gas, pressure, and flow velocity. The model shows excellent agreement with experimental deposition rates without parameter tuning and demonstrates that gas‑phase kinetics are crucial for silicon CVD.

Abstract

We describe a numerical model of the coupled gas‐phase hydrodynamics and chemical kinetics in a silicon chemical vapor deposition (CVD) reactor. The model, which includes a 20‐step elementary reaction mechanism for the thermal decomposition of silane, predicts gas‐phase temperature, velocity, and chemical species concentration profiles. It also predicts silicon deposition rates at the heated reactor wall as a function of susceptor temperature, carrier gas, pressure, and flow velocity. We find excellent agreement with experimental deposition rates, with no adjustment of parameters. The model indicates that gas‐phase chemical kinetic processes are important in describing silicon CVD.