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We describe a mathematical model of the coupled fluid mechanics and gas‐phase chemical kinetics in a rotating disk chemical vapor deposition reactor. The analysis is for the flow between an infinite radius, heated nonporous rotating disk and a parallel infinite radius porous surface through which reactive fluid is injected normal to the disk. The analysis extends the usual von Karman transformation to allow specification of the normal velocity at the porous disk, and reduces to a stagnation point flow in the limit of zero rotating rate. The deposition of silicon from silane is used as an example system. A new reaction mechanism and set of rate constants are given for the thermal decomposition of silane. We present an RRKM analysis of several of the unimolecular reactions in the mechanism. Calculated velocity and temperature profiles, chemical species density profiles, and deposition rates as functions of susceptor temperature, spin rate, and inlet flow velocity are presented.

This report documents the SPIN Fortran computer program that computes species, temperature and velocity profiles, and deposition rates in a steady-state one-dimensional rotating disk or stagnation-point flow chemical vapor deposition (CVD) reactor. The program accounts for finite-rate gas-phase and surface chemical kinetic and multicomponent molecular transport. The governing differential equations form a two-* This document describes the features in version 3.83. We expect that this software package will continue to evolve, and thus later versions may render portions of this document out of date.

Steady, laminar, axisymmetric, and circumferentially uniform flow and heat transfer, including the effects of variable properties and buoyancy, have been modeled within a rotating disk chemical vapor deposition (CVD) reactor. The reactor is oriented vertically, with the hot, isothermal, spinning disk facing upward. The Navier–Stokes and energy equations have been solved for the carrier gas helium. The solutions have been obtained over a range of parameters, which is of importance in CVD applications. The primary parameters are the ratio of the disk temperature to the free stream temperature Tw/T∞, the disk Reynolds number Re = rd2ω/ν∞, a mixed convection parameter Gr/Re3/2 = g(ρ∞ − ρw)/(ρwωων∞), the dimensionless inlet velocity u∞/ων∞, and two geometric parameters ro/rd and L/rd. Results are obtained for the velocity and the temperature fields and for the heat flux at the surface of the rotating disk. Comparisons are made with the one-dimensional, variable-property (excluding buoyant effects), infinite rotating disk solutions of Pollard and Newman. Results are presented in terms of a local Nusselt number. The potential uniformity of CVD in this geometry can be inferred from the variation of the Nusselt number over the surface of the rotating disk. The effects of buoyancy and the finite size of the rotating disk within the cylindrical reactor are clearly evident in the present work.

A research chemical vapor deposition reactor design is presented for a rotating disk configuration. The reactor can be operated under conditions such that nearly ideal, one-dimensional, infinite-radius disk behavior is achieved over most of the disk surface. Boundary conditions, flow stability under both isothermal and heated-disk conditions, and gas temperatures are addressed with both one-and two-dimensional numerical fluid mechanics models. Experimental verification of the design using flow visualization and laser Raman thermometry are presented.

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