Hydrodynamic description of vapor levitation epitaxy

Recently a new concept of an epitaxial growth technique called vapor levitation epitaxy (VLE) has been published. In this technique the substrate is floated above the growth apparatus by the flow of vapors emerging through a porous disc. In the limit of certain simplifications the VLE process is analysed by means of an analytical solution of the balance equations for flow and chemical species. The VLE reactor is treated as a special case of the ideal stagnation point flow configuration. The dependence of the flow on the Reynolds number is investigated. Deposition rates are calculated for the case of transport-limited growth conditions. In addition the effect of surface kinetics is taken into consideration via a first order reaction mechanism. Results are presented in terms of dimensionless numbers and the limits of the different regimes are discussed.