Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-29T14:21:43.410Z Has data issue: false hasContentIssue false

The onset of transverse recirculations during flow of gases in horizontal ducts with differentially heated lower walls

Published online by Cambridge University Press:  26 April 2006

N. K. Ingle
Affiliation:
Department of Chemical Engineering and Center for Electronic and Electro-optic Materials, State University of New York, Buffalo, NY 14260, USA
T. J. Mountziaris
Affiliation:
Department of Chemical Engineering and Center for Electronic and Electro-optic Materials, State University of New York, Buffalo, NY 14260, USA

Abstract

A computational study has been performed to identify the onset of transverse buoyancy-driven recirculations during laminar flow of hydrogen and nitrogen in horizontal ducts with cool upper walls, and lower walls consisting of three sections: a cool upstream section, a heated middle section and a cool downstream section. The motivation for this work stems from the need to identify operating conditions maximizing the thickness uniformity, the interface abruptness and the precursor utilization during growth of thin films and multi-layer structures of semiconductors by metalorganic chemical vapour deposition (MOCVD). A mathematical model describing the flow and heat transfer along the vertical midplane of MOCVD reactors with the above geometry has been developed and computer simulations were performed for a variety of operating conditions using the Galerkin finite-element method. At atmospheric pressure and low inlet velocities, transverse recirculations form near the upstream and downstream edges of the heated section. These can be suppressed either by increasing the inlet velocity of the gas, so that forced convection dominates natural convection, or by decreasing the operating pressure to reduce the effects of buoyancy. The onset of transverse recirculations has been determined for Grashof (Gr) and Reynolds (Re) numbers covering the following ranges: 10−3 < Re < 100 and 1 < Gr < 106, with Gr and Re computed using fluid properties at the inlet conditions. The computations indicate that, for abrupt temperature changes along the lower wall (worst-case scenario), transverse recirculations are always absent if the following criteria are satisfied: \[(Gr/Re) < 100\quad {\rm for}\quad 10^{-3} < Re \leqslant 4\quad {\rm and}\quad (Gr/Re^2) < 25\quad {\rm for}\quad 4 \leqslant Re < 100.\]

The predicted critical values of Re, which correspond to the onset of transverse recirculations, agree well with reported experimental observations. The above criteria can be used for optimal design and operation of horizontal MOCVD reactors and may also be useful for heat transfer studies in horizontal ducts with differentially heated lower walls.

Type
Research Article
Copyright
© 1994 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Ban, V. S. 1978 Transport phenomena measurements in epitaxial reactors. J. Electrochem. Soc. 125, 317320.Google Scholar
Chandrasekhar, S. 1981 Hydrodynamic and Hydromagnetic Stability. Dover.
Chinoy, P. B., Agnello, P. D. & Ghandhi, S. K. 1988 An experimental and theoretical study of growth in horizontal epitaxial reactors. J. Electron. Mater. 17, 493499.Google Scholar
Chiu, K.-C., Ouazzani, J. & Rosenberger, F. 1987 Mixed convection between horizontal plates - II. fully developed flow. Intl J. Heat Mass Transfer 30, 16551662.Google Scholar
Chiu, K.-C. & Rosenberger, F. 1987 Mixed convection between horizontal plates - I. Entrance effects. Intl J. Heat Mass Transfer 30, 16451654.Google Scholar
Deardorff, J. W. 1965 Gravitational instability between horizontal plates with shear. Phys. Fluids 8, 10271030.Google Scholar
Evans, G. & Greif, R. 1989 A study of traveling wave instabilities in a horizontal channel flow with applications to chemical vapor deposition. Intl J. Heat Mass Transfer 32, 895911.Google Scholar
Evans, G. & Greif, R. 1991 Unsteady three-dimensional mixed convection in a heated horizontal channel with applications to chemical vapor deposition. Intl J. Heat Mass Transfer 34, 20392051.Google Scholar
Evans, G. & Greif, R. 1993 Thermally unstable convection with applications to chemical vapor deposition channel reactors. Intl J. Heat Mass Transfer 36, 27692781.Google Scholar
Eversteyn, F. C., Severin, P. J. W., Van Der Brekel, C. H. J. & Peek, H. L. 1970 A stagnant layer model for the epitaxial growth of silicon from silane in a horizontal reactor. J. Electrochem. Soc. 117, 925931.Google Scholar
Field, R. J. 1989 Simulations of two-dimensional recirculating flow effects in horizontal MOVPE. J. Cryst. Growth 97, 739760.Google Scholar
Field, R. J. & Ghandhi, S. K. 1984 The growth of GaAs at reduced pressure in an organometallic CVD system. J. Cryst. Growth 69, 581588.Google Scholar
Fotiadis, D. I., Boekholt, M., Jensen, K. F. & Richter, W. 1990 Flow and heat transfer in CVD reactors: Comparison of Raman temperature measurements and finite element model predictions. J. Cryst. Growth 100, 577599.Google Scholar
Fotiadis, D. I. & Jensen, K. F. 1990 Thermophoresis of solid particles in horizontal chemical vapor deposition reactors. J. Cryst. Growth 102, 743761.Google Scholar
Gallagher, A. P. & Mercer, A. McD. 1965 On the behaviour of small disturbances in plane Couette flow with a temperature gradient. Proc. R. Soc. Lond. A 286, 117128.Google Scholar
Giling, L. J. 1982 Gas flow patterns in horizontal epitaxial reactor cells observed by interference holography. J. Electrochem. Soc. 129, 634644.Google Scholar
Holstein, W. L. & Fitzjohn, J. L. 1989 Effect of buoyancy forces and reactor orientation on fluid flow and growth rate uniformity in cold-wall channel CVD reactors. J. Cryst. Growth 94, 145158.Google Scholar
Jensen, K. F., Einset, E. O. & Fotiadis, D. I. 1991 Flow phenomena in chemical vapor deposition of thin films. Ann. Rev. Fluid Mech. 23, 197232.Google Scholar
Ludowise, M. J. 1985 Metalorganic chemical vapour deposition of III-V semiconductors. J. Appl. Phys. 58, R31R55.Google Scholar
McCabe, W. L., Smith, J. C. & Harriott, P. 1985 Unit Operations of Chemical Engineering. McGraw-Hill.
Moffat, H. & Jensen, K. F. 1986 Complex flow phenomena in MOCVD reactors I. Horizontal reactors. J. Cryst. Growth 77, 108119.Google Scholar
Mori, Y. 1961 Buoyancy effects in forced convection flow over a horizontal flat plate. Trans. ASME C: J. Heat Transfer 83, 479482.Google Scholar
Mountziaris, T. J., Kalyanasundaram, S. & Ingle, N. K. 1993 A reaction-transport model of GaAs growth by metalorganic chemical vapor deposition using trimethyl-gallium and tertiary-butyl-arsine. J. Cryst. Growth 131, 283299.Google Scholar
Ouazzani, J., Chiu, K.-C. & Rosenberger, F. 1988 On the 2D modelling of horizontal CVD reactors and its limitations. J. Cryst. Growth 91, 497508.Google Scholar
Ouazzani, J. & Rosenberger, F. 1990 Three-dimensional modelling of horizontal chemical vapor deposition. I. MOCVD at atmospheric pressure. J. Cryst. Growth 100, 545576.Google Scholar
Perry, R. H. & Chilton, C. H. 1973 Chemical Engineers’ Handbook (5th edn). McGraw-Hill.
Robertson, G. E., Seinfeld, J. H. & Leal, L. G. 1973 Combined forced and free convection flow past a horizontal flat plate. AIChE J. 19, 9981008.Google Scholar
Sparrow, E. M. & Minkowycz, W. J. 1962 Buoyancy effects on horizontal boundary-layer flow and heat transfer. Intl J. Heat Mass Transfer 5, 505511.Google Scholar
Stock, L. & Richter, W. 1986 Vertical versus horizontal reactor: An optical study of the gas phase in an MOCVD reactor. J. Cryst. Growth 77, 144150.Google Scholar
Strang, G. & Fix, G. 1973 An Analysis of the Finite Element Method. Prentice Hall.
Ven J. Van De, Rutten, G. J. M., Raaymakers, M. J. & Giling, L. J. 1986 Gas phase depletion and flow dynamics in horizontal MOCVD reactors. J. Cryst. Growth 76, 352372.Google Scholar
Visser, E. P., Kleijn, C. R., Govers, C. A. M., Hoogendoorn, C. J. & Giling, L. J. 1989 Return flows in horizontal MOCVD reactors studied with the use of TiO2 particle injection and numerical calculations. J. Cryst. Growth 94, 929945; and errata 96, 1989, 732–735.Google Scholar