scholarly journals A Design Method to Improve Temperature Uniformity on Wafer for Rapid Thermal Processing

Electronics ◽  
2018 ◽  
Vol 7 (10) ◽  
pp. 213
Author(s):  
Peng Huang ◽  
Hongguan Yang
Keyword(s):  
Temperature Distribution ◽  
Thermal Processing ◽  
Design Method ◽  
Rapid Thermal Processing ◽  
Design Parameters ◽  
Temperature Uniformity ◽  
Uniform Temperature ◽  
Simple Method ◽  
Uniform Temperature Distribution ◽  
Proposed Model

Single-wafer rapid thermal processing (RTP) is widely used in semiconductor manufacturing. Achieving temperature uniformity on silicon wafer is a major challenge in RTP control. In this work, a lamp configuration including five concentric lamp zones is designed to obtain uniform temperature distribution on the wafer. An optics-based model is developed to determine the optimal lamp design parameters, and a uniformity criterion is proposed to evaluate the effective irradiance distribution of the tungsten–halogen lamps on the wafer. This method can be used to determine geometric parameters of the lamp array in order to achieve uniform temperature distribution on the wafer. A realistic simulation of a cold wall RTP system with five lamp rings and a 200-mm wafer is performed. The proposed model makes way for a simple method for determining the optimal lamp design parameters in RTP systems.

Modelling of Temperature Distribution of Semiconductors During Rapid Thermal Processing

1994 ◽  
Vol 342 ◽  
Author(s):  
Andreas Tillmann
Keyword(s):  
Temperature Distribution ◽  
Material Property ◽  
Thermal Processing ◽  
Rapid Thermal Processing ◽  
Two Dimensional ◽  
Temperature Uniformity ◽  
Temperature Dependent ◽  
Incident Intensity ◽  
Circular Test ◽  
Contour Plots

ABSTRACTThe modelling of temperature distribution on semiconductor wafers in common RTP-equipment is described. The incident intensity distribution on the wafer is calculated using raytracing. Based on this distribution the temperature distribution on the wafer is determined solving the two-dimensional heat conduction equation. If the dependence of a considered material property on the process temperature is known, the calculated temperature distribution can be convened to a distribution of this parameter.The distinctive feature of the described algorithms is the two-dimensional treatment of the distributions using a grid of ring segments, each with equal area. This grid is identical to the usual circular test patterns of multipoint measurement equipment. This is convenient since the evaluation of temperature uniformity in RTP equipment is done mostly by mapping an appropriate temperature dependent material property. All calculated distributions can be presented by contour plots as well as 3-D plots. This results in a very suitable method to compare simulated and experimental wafer maps.The agreement between simulated and experimental temperature distributions is shown.

The Assessment of the Temperature Uniformity in Processing Small Food Objects

2005 ◽  
Vol 1 (3) ◽  
Author(s):  
Xiao Dong Chen
Keyword(s):  
Temperature Distribution ◽  
Biot Number ◽  
Evaporative Cooling ◽  
The Other ◽  
Temperature Uniformity ◽  
Uniform Temperature ◽  
Cooling Process ◽  
Surface Evaporation ◽  
Uniform Temperature Distribution ◽  
Internal Generation

Conventionally, a small Biot number must be ensured to proceed with the assumption of the uniform temperature distribution within the material (being heated or cooled, or dried) of interest. In this communication, several situations are analysed, i.e. internal generation or dissipation and surface evaporation while the material being heated illustrating the above rule can be relaxed. On the other hand, when considering the surface evaporative cooling process, derivations made have shown that the criterion is in fact too generous. The study provides useful formula for justifying the assumption of uniform temperature within the small objects being processed.

Improvement of Temperature Uniformity in Rapid Thermal Processing Systems Using Multivariable Control

1991 ◽  
Vol 224 ◽  
Author(s):  
S. A. Norman ◽  
C. D. Schaper ◽  
S. P. Boyd
Keyword(s):  
Steady State ◽  
Temperature Distribution ◽  
Thermal Processing ◽  
Numerical Technique ◽  
Rapid Thermal Processing ◽  
Temperature Uniformity ◽  
Wafer Temperature ◽  
Scalar Control ◽  
Steady State Temperature ◽  
Knob Control

AbstractDuring rapid thermal processing (RTP) of a semiconductor wafer, maintenance of nearuniform wafer temperature distribution is necessary. This paper addresses the problem of insuring temperature uniformity in a cylindrical RTP system with multiple concentric circular lamps.A numerical technique is presented for optimizing steady-state temperature distribution by independently varying the power radiated by each lamp. It is shown for a simulated system, over a wide range of temperature setpoints, that the temperature uniformity achievable with multivariable (“multiple knob”) control of lamp powers is significantly better than that achievable with scalar (“single knob”) control.The difficulties of using scalar control in RTP are more severe in the case of temperature trajectory design than in the case of steady-state temperature maintenance. For example, with scalar control the rate of temperature increase during ramping is limited because temperature nonuniformity can cause slip defects in the wafer. A numerical technique is presented for designing multivariable lamp power trajectories to obtain near-optimal temperature uniformity while wafer temperature tracks a specified ramp, resulting in slip-free ramp rates much faster than those achievable with scalar control.

scholarly journals Mixed convection in sinusoidal lid driven cavity with non-uniform temperature distribution on the wall utilizing nanofluid

Heliyon ◽  
2021 ◽  
Vol 7 (5) ◽  
pp. e06907
Author(s):  
Sattar Aljabair ◽  
Ali L. Ekaid ◽  
Sahira Hasan Ibrahim ◽  
Israa Alesbe
Keyword(s):  
Temperature Distribution ◽  
Mixed Convection ◽  
Uniform Temperature ◽  
Driven Cavity ◽  
Uniform Temperature Distribution

A model to design high-pressure processes towards an uniform temperature distribution

2007 ◽  
Vol 78 (4) ◽  
pp. 1463-1470 ◽  
Author(s):  
L. Otero ◽  
A.M. Ramos ◽  
C. de Elvira ◽  
P.D. Sanz
Keyword(s):  
High Pressure ◽  
Temperature Distribution ◽  
Uniform Temperature ◽  
Uniform Temperature Distribution

Non-uniform temperature distribution of the main reflector of a large radio telescope under solar radiation

2021 ◽  
Vol 21 (11) ◽  
pp. 293
Author(s):  
Shan-Xiang Wei ◽  
De-Qing Kong ◽  
Qi-Ming Wang
Keyword(s):  
Temperature Field ◽  
Temperature Distribution ◽  
Solar Radiation ◽  
Radio Telescope ◽  
Thermal Imaging ◽  
Uniform Temperature ◽  
Large Radio Telescope ◽  
Uniform Temperature Distribution ◽  
Uniform Temperature Field ◽  
Main Reflector

Abstract The non-uniform temperature distribution of the main reflector of a large radio telescope may cause serious deformation of the main reflector, which will dramatically reduce the aperture efficiency of a radio telescope. To study the non-uniform temperature field of the main reflector of a large radio telescope, numerical calculations including thermal environment factors, the coefficients on convection and radiation, and the shadow boundary of the main reflector are first discussed. In addition, the shadow coverage and the non-uniform temperature field of the main reflector of a 70-m radio telescope under solar radiation are simulated by finite element analysis. The simulation results show that the temperature distribution of the main reflector under solar radiation is very uneven, and the maximum of the root mean square temperature is 12.3°C. To verify the simulation results, an optical camera and a thermal imaging camera are used to measure the shadow coverage and the non-uniform temperature distribution of the main reflector on a clear day. At the same time, some temperature sensors are used to measure the temperature at some points close to the main reflector on the backup structure. It has been verified that the simulation and measurement results of the shadow coverage on the main reflector are in good agreement, and the cosine similarity between the simulation and the measurement is above 90%. Despite the inevitable thermal imaging errors caused by large viewing angles, the simulated temperature field is similar to the measured temperature distribution of the main reflector to a large extent. The temperature trend measured at the test points on the backup structure close to the main reflector without direct solar radiation is consistent with the simulated temperature trend of the corresponding points on the main reflector with the solar radiation. It is credible to calculate the temperature field of the main reflector through the finite element method. This work can provide valuable references for studying the thermal deformation and the surface accuracy of the main reflector of a large radio telescope.

Embedded resistive heating in composite scarf repairs

2016 ◽  
Vol 51 (18) ◽  
pp. 2575-2583 ◽  
Author(s):  
Mahdi Ashrafi ◽  
Brandon P Smith ◽  
Santosh Devasia ◽  
Mark E Tuttle
Keyword(s):  
Temperature Distribution ◽  
Outer Surface ◽  
Thermal Gradient ◽  
Thermal Damage ◽  
Electrical Current ◽  
Tensile Tests ◽  
Resistance Heating ◽  
Uniform Temperature ◽  
Uniform Temperature Distribution ◽  
Bond Strengths

Composite scarf repairs were cured using heat generated by passing an electrical current through a woven graphite-epoxy prepreg embedded in the bondline. Resistance heating using the embedded prepreg resulted in a more uniform temperature distribution in the bondline while preventing any potential thermal damage to the surface of the scarf repairs. In contrast, conventional surface heating methods such as heat blankets or heat lamps lead to large through thickness thermal gradient that causes non-uniform temperature in the bondline and overheating the outer surface adjacent to the heater. Composite scarf repair specimens were created using the proposed embedded heating approach and through the use of a heat blanket for circular and rectangular scarf configurations. Tensile tests were performed for rectangular scarf specimens, and it was shown that the bond strengths of all specimens were found to be comparable. The proposed embedded curing technique results in bond strengths that equal or exceed those achieved with external heating and avoids overheating the surface of the scarf repairs.

scholarly journals Enhancement of Exit Flow Uniformity by Modifying the Shape of a Gas Torch to Obtain a Uniform Temperature Distribution on a Steel Plate during Preheating

2018 ◽  
Vol 8 (11) ◽  
pp. 2197
Author(s):  
Thien Ngo ◽  
Junho Go ◽  
Tianjun Zhou ◽  
Hap Nguyen ◽  
Geun Lee
Keyword(s):  
Temperature Distribution ◽  
Temperature Difference ◽  
Steel Plate ◽  
Flow Distribution ◽  
Uniform Temperature ◽  
Flow Uniformity ◽  
Modified Model ◽  
Uniform Temperature Distribution ◽  
Basic Model ◽  
New Models

The objective of this study is to improve the exit flow uniformity of a gas torch with multiple exit holes for effective heating of a steel plate. The torch was simulated, and combustion experiments were performed for validation. Based on a basic model, three different revised models were designed and analyzed with the software ANSYS FLUENT 18.2. The flow uniformity (γ) of the velocity distribution at the multiple exit holes was investigated with the pressure drop ranging from 100 to 500 Pa. The basic model had flow uniformity ranging from 0.849 to 0.852, but the three new models had γ1 = 0.901–0.912, γ2 = 0.902–0.911, and γ3 = 0.901–0.914, respectively. The maximum percentage difference of the flow uniformity index between the three new models and the basic model was 7.3%. The basic model with nonuniform flow distribution made a temperature difference of the back side of the steel plate from the center to the edge of around 229 °C, while the modified model with uniform flow distribution had a smaller temperature difference of 90 °C. The simulation results showed good agreement with our experimental results for both the basic model and the modified model. The modified gas torch made a wider and more uniform temperature distribution on a preheated steel plate than the basic one. The results revealed that a trade-off between cost and flow uniformity, as well as the new gas torch, could be applied to a steel-plate preheating process before welding.

Investigation on non-uniform temperature distribution in a solar cell with associated laser beam heating

Solar Energy ◽  
2021 ◽  
Vol 213 ◽  
pp. 172-179
Author(s):  
Han Zhai ◽  
Jia Zhang ◽  
Zihua Wu ◽  
Huaqing Xie ◽  
Qiang Li
Keyword(s):  
Solar Cell ◽  
Temperature Distribution ◽  
Laser Beam ◽  
Uniform Temperature ◽  
Uniform Temperature Distribution ◽  
Beam Heating ◽  
Laser Beam Heating
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