Simulation of Rapid Thermal Processing Equipment and Processes

1993 ◽  
Vol 303 ◽  
Author(s):  
Kun-Ho Lie ◽  
Tushar P. Merchant ◽  
Klavs F. Jensen
Keyword(s):  
Heat Transfer ◽  
Thermal Processing ◽  
Gas Flow ◽  
Transient Flow ◽  
Radiation Heat Transfer ◽  
Rapid Thermal Processing ◽  
Operating Conditions ◽  
Multiple Reflections ◽  
Design And Optimization ◽  
Process Gas

ABSTRACTWe present finite element simulations of fluid flow, heat transfer, and chemical reactions in axisymmetric rapid thermal processing (RTP) configurations. A new approach to simulating radiation heat transfer between lamps, substrates, and system walls is described. The method accounts for multiple reflections and readily allows the inclusion of temperature, radiation wavelength, and materials specific emissivity parameters. The influence of system geometry, lamp power profile, substrate and wall emissivity parameters, and process gas flow upon RTP performance characteristics is illustrated through examples. Transient flow and heat transfer simulations are used to identify operating conditions where flow recirculations are avoided. The further use of physically based models in the design and optimization of RTP systems is discussed.

Monte Carlo Simulation of Radiative Heat Transfer in Rapid Thermal Processing (RTP) Systems

1994 ◽  
Vol 342 ◽  
Author(s):  
J. Vernon Cole ◽  
Karson L. Knutson ◽  
Klavs F. Jensen
Keyword(s):  
Heat Transfer ◽  
Monte Carlo ◽  
Thermal Processing ◽  
Measurement Techniques ◽  
Radiation Heat Transfer ◽  
Rapid Thermal Processing ◽  
Three Dimensional ◽  
General Purpose ◽  
Radiation Heat ◽  
Participating Media

ABSTRACTWe present a general purpose Monte Carlo method for the simulation of radiation heat transfer in rapid thermal processing (RTP) chambers. Three-dimensional mesh generation software is used to discretize the surfaces within the system, allowing the simulation of realistic chamber and reflector designs. An adaptive subdivision of the chamber geometry reduces the number of raysurface intersections which must be computed. The method models internal reflection, absorption, and transmission within participating media, and includes wavelength, temperature, and material dependent optical properties. Radiation heat transfer simulations are used to examine a reflector assembly, and to test the assumptions of optical wafer temperature measurement techniques.

scholarly journals Design and Optimization of Chemical Mixing System for Vacuum Chambers: Simulation Results

2014 ◽  
Vol 5 ◽  
Author(s):  
Faruk Unker ◽  
Erdar Kaplan ◽  
Olkan Cuvalci
Keyword(s):  
Gas Flow ◽  
Flow Behavior ◽  
Atomic Layer ◽  
Flow Patterns ◽  
Operating Conditions ◽  
Tantalum Nitride ◽  
Ansys Fluent ◽  
Design And Optimization ◽  
Parametric Investigation ◽  
Process Gas

Computational fluid dynamics (CFD) is widely used in device design to determine gas flow patterns and turbulence levels.  CFD is also used to simulate particles and droplets, which are subjected to various forces, turbulence and wall interactions. These studies can now be performed routinely because of the availability of commercial software containing high quality turbulence and particle models. In order to understand how the gas is brought down to wafer, it is necessary to have a knowledge of the gas flow behavior very early in the design spiral of the Tantalum nitride-Atomic layer deposition(TaN-ALD) chamber by undertaking parametric investigation of the interaction effect between gas flow and the funnel structure. This paper presents such a  parametric  investigation on a generic TaN-ALD chamber using CFD. The results presented have been analyzed for a total of 11 different cases by varying neck and nozzle angles for a process gas. The gas flow was mainly investigated for the nozzle angles of  4.5◦,  9◦,  12◦  and  20◦ and the film thickness results were compared with numerical flow patterns. CFD simulations using the turbulence model in ANSYS Fluent v.13 are undertaken. The parametric study has demonstrated that CFD is a powerful tool to study the problem of gas flow-structure interaction on funnel and is capable of providing a means of visualizing the path of the gas under different operating conditions

Modeling of a Gallium Nitride Epitaxy Growth System

2004 ◽  
Author(s):  
D. Cai ◽  
B. Wu ◽  
L. L. Zheng ◽  
H. Zhang ◽  
W. J. Mecouch ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Boundary Condition ◽  
Gallium Nitride ◽  
Heterogeneous Reaction ◽  
Radiation Heat Transfer ◽  
Tubular Reactor ◽  
Nitride Layer ◽  
Operating Conditions ◽  
North Carolina State University ◽  
Design And Optimization

An iodine vapor phase epitaxy (IVPE) system has been designed and built at North Carolina State University to grow high quality thick gallium nitride layer at the growth rate up to 80 μm/h with the deposition temperature of 1010 °C and the pressure of 200 Torr. In order to optimize the growth process, a numerical model, which is capable of describing multi-component fluid flow, gas/surface chemistry, conjugate heat transfer, radiation heat transfer and multi-species transport, has been developed to help in design and optimization of the IVPE reactor. The gallium source weight reduce rate is converted into flow rate of gallium vapor and has been simulated as an inlet boundary condition of the tubular reactor. By matching predicted and experimental deposition rates, the heterogeneous reaction boundary condition is determined and applied to the substrate. Comprehensive two-dimensional computational simulations have been performed to study the temperature distribution, species mixing process and GaN deposition rate distribution on the substrate under different geometrical configurations and operating conditions; and the operating parameters have been optimized.

Transient And Spatial Radiative Properties Of Patterned Wafers During Rapid Thermal Processing

1995 ◽  
Vol 387 ◽  
Author(s):  
Peter Y. Wong ◽  
Ioannis N. Miaoulis ◽  
Cynthia G. Madras
Keyword(s):  
Heat Transfer ◽  
Heat Source ◽  
Thermal Processing ◽  
Rapid Thermal Processing ◽  
Temporal Variations ◽  
Radiative Properties ◽  
Wafer Surface ◽  
Patterned Wafers ◽  
Thermal Radiative Properties ◽  
Dynamic Variations

AbstractTemperature measurements and processing uniformity continue to be major issues in Rapid Thermal Processing. Spatial and temporal variations in thermal radiative properties of the wafer surface are sources of non-uniformities and dynamic variations. These effects are due to changes in spectral distribution (wafer or heat source), oxidation, epitaxy, silicidation, and other microstructural transformations. Additionally, other variations are induced by the underlying (before processing) and developing (during processing) patterns on the wafer. Numerical simulations of Co silicidation that account for these factors are conducted to determine the radiative properties, heat transfer dynamics, and resultant processing uniformity.

Experimental Inverstigations On the Pressure Fluctuations in the Sealing Gap of Dry Gas Seals with Embedded Pressure Sensors

2021 ◽  
Author(s):  
Jingjing Luo ◽  
Dieter Brillert
Keyword(s):  
High Speed ◽  
Gas Flow ◽  
Static Pressure ◽  
Pressure Sensors ◽  
Operating Conditions ◽  
Test Facility ◽  
Experimental Investigations ◽  
Mechanical Seals ◽  
Process Gas ◽  
Sealing Gap

Abstract Dry gas lubricated non-contacting mechanical seals (DGS), most commonly found in centrifugal compressors, prevent the process gas flow into the atmosphere. Especially when high speed is combined with high pressure, DGS is the preferred choice over other sealing alternatives. In order to investigate the flow field in the sealing gap and to facilitate the numerical prediction of the seal performance, a dedicated test facility is developed to carry out the measurement of key parameters in the gas film. Gas in the sealing film varies according to the seal inlet pressure, and the thickness of gas film depends on this fluctuated pressure. In this paper, the test facility, measurement methods and the first results of static pressure measurements in the sealing gap of the DGS obtained in the described test facility are presented. An industry DGS with three-dimensional grooves on the surface of the rotating ring, where experimental investigations take place, is used. The static pressure in the gas film is measured, up to 20 bar and 8,100 rpm, by several high frequency ultraminiature pressure transducers embedded into the stationary ring. The experimental results are discussed and compared with the numerical model programmed in MATLAB, the characteristic and magnitude of which have a good agreement with the numerical simulations. It suggests the feasibility of measuring pressure profiles of the standard industry DGS under pressurized dynamic operating conditions without altering the key components of the seal and thereby affecting the seal performance.

Parametric height influence analysis on thermal radiation and convection applied to real ovens

2021 ◽  
pp. 095440892110375
Author(s):  
Sílvio Aparecido Verdério Júnior ◽  
Vicente Luiz Scalon ◽  
Santiago del Rio Oliveira ◽  
Elson Avallone ◽  
Paulo César Mioralli ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Radiation ◽  
Numerical Models ◽  
Radiation Heat Transfer ◽  
Geometric Optimization ◽  
Operating Conditions ◽  
High Productivity ◽  
Order Of Magnitude ◽  
Lower Height ◽  
Heat Exchanges

Due to their greater flexibility in heating and high productivity, continuous tunnel-type ovens have become the best option for industrial processes. The geometric optimization of ovens to better take advantage of the heat transfer mechanisms by convection and thermal radiation is increasingly researched; with the search for designs that combine lower fuel consumption, greater efficiency and competitiveness, and lower costs. In this sense, this work studied the influence of height on heat exchanges by radiation and convection and other flow parameters to define the best geometric height for the real oven under study. From the dimensions and real operating conditions of continuous tunnel-type ovens were built five numerical models of parametric variation, which were simulated with the free and open-source software OpenFOAM®. The turbulent forced convection regime was characterized in all models. The use of greater heights in the ovens increased and intensified the recirculation regions, reduced the rates of heat transfer by thermal radiation, and reduced the losses of heat by convection. The order of magnitude of heat exchanges by radiation proved to be much higher than heat exchanges by convection, confirming the results of the main references in the technical-scientific literature. It was concluded that the use of ovens with a lower height provides significant increases in the thermal radiation heat transfer rates.

Investigation of the Flow Phenomenon Inside Gas Ejectors With Moist Gas Entrainment

2016 ◽  
Vol 9 (1) ◽  
Author(s):  
Yuping Wang ◽  
Mark Pellerin ◽  
Pravansu Mohanty ◽  
Subrata Sengupta
Keyword(s):  
Water Vapor ◽  
Phase Change ◽  
Gas Flow ◽  
Phase Distribution ◽  
Light Attenuation ◽  
Three Dimensional ◽  
Operating Conditions ◽  
Second Phase ◽  
Symmetric Model ◽  
Design And Optimization

This paper focuses on the gas flow study of an ejector used in applications where moist gases are being entrained. Two parts of work are presented. In the first part, characteristics of gas flow inside an ejector, as well as the ejector's performance under various operating and geometric configurations, were studied with a three-dimensional computational model. Measurements were also performed for validation of the model. In the second part, focus was given to the potential condensation or desublimation phenomena that may occur inside an ejector when water vapor is included in the entrained stream. Experiments using light-attenuation method were performed to verify the presence of a second phase; then, the onset of phase change and the phase distribution were obtained numerically. A two-dimensional axis-symmetric model was developed based on the model used in the first part. User-defined functions were used to implement the phase-change criteria and particle prediction. A series of simulations were performed with various amounts of water vapor added into the entrained flow. It was found that both frost particles and water condensate could form inside the mixing tube depending on the operating conditions and water vapor concentrations. When the concentration exceeds 3% by mass, water vapor could condense throughout the mixing tube. Some preliminary results of the second phase particles formed, e.g., critical sizes and distributions, were also obtained to assist with the design and optimization of gas ejectors used in similar applications.

Improved MSMGFSK Models Apply to Gas Radiation Heat Transfer Calculation of Exhaust System of TBCC

2016 ◽  
Vol 139 (1) ◽  
Author(s):  
Haiyang Hu ◽  
Qiang Wang
Keyword(s):  
Heat Transfer ◽  
Gas Flow ◽  
Thermal Emission ◽  
Radiation Heat Transfer ◽  
Exhaust System ◽  
Combined Cycle ◽  
Large Temperature ◽  
Radiation Heat ◽  
Full Spectrum ◽  
Radiation Emission

The multiscale multigroup full-spectrum k-distribution (MSMGFSK) model was improved to adapt to radiation heat transfer calculations of combustion gas flow field with large temperature and pressure gradient. The improvements in calculation accuracy resulting from new sorting strategy of the spectral absorption coefficients were validated using a series of semi-1D problem in which strong temperature, pressure, and mole fraction inhomogeneities were present. A simpler method to attain compatibility between the MSMGFSK model and the gray-wall radiation emission has been established and validated. Finally, estimates are given for the calculation of wall radiation heat transfer characteristics and thermal emission imaging of the exhaust system of the parallel turbine-based combined cycle (TBCC) engine, using finite volume method (FVM) and ray trace method (RT), respectively.

Steady-state thermal uniformity and gas flow patterns in a rapid thermal processing chamber

1991 ◽  
Vol 4 (1) ◽  
pp. 14-20 ◽  
Author(s):  
S.A. Campbell ◽  
K.-H. Ahn ◽  
K.L. Knutson ◽  
B.Y.H. Liu ◽  
J.D. Leighton
Keyword(s):  
Steady State ◽  
Thermal Processing ◽  
Gas Flow ◽  
Rapid Thermal Processing ◽  
Flow Patterns

Effects of Various Reactions on the Gas Flow and Heat Transfer in an Anode Duct of ITSOFCs

2005 ◽  
Author(s):  
Jinliang Yuan ◽  
Bengt Sunde´n
Keyword(s):  
Heat Transfer ◽  
Gas Flow ◽  
Porous Electrode ◽  
Gas Permeation ◽  
Transport Processes ◽  
Operating Conditions ◽  
Electrochemical Reactions ◽  
Fuel Gas ◽  
Internal Reforming ◽  
Porous Anode

Recently, there has been considerable interest in the internal reforming reactions of solid oxide fuel cells (SOFCs) using methane or natural gas via. The internal reforming and electrochemical reactions appear in the porous anode layer, and may lead to inhomogeneous temperature and gas species distributions according to the reaction kinetics. A three-dimensional calculation method has been further developed to simulate and analyze the internal reforming and the electrochemical reactions, and the effects on various transport processes in a thick anode duct. In this study, the composite duct consists of a porous anode, fuel flow duct and solid current connector. Momentum, heat transport and gas species equations have been solved by coupled source terms and variable physical properties (density, viscosity, specific heat, etc.) of the fuel gas mixture. The combined thermal boundary conditions on solid walls, mass balances (generation and consumption) associated with the various reactions and gas permeation to/from the porous electrode are applied in the analysis. Simulation results show that the internal reforming and the electrochemical reactions, and operating conditions are significant for fuel gas transport and heat transfer in the anode.

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