Partial Transparency Effects of Silicon During Rapid Thermal Processing

ABSTRACTThe radiative properties of a silicon wafer undergoing Rapid Thermal Processing (RTP) are contingent upon the doping level of the silicon substrate and film structure on the wafer, and fluctuate drastically with temperature and wavelength. For a lightly doped substrate, partial transparency effects must be considered that significantly affect absorption characteristics. Band gap, free carrier, and lattice absorption are the dominant absorption mechanisms and either individually or in concert have considerable effect on the overall absorption coefficient of the silicon wafer. At high doping levels, partial transparency effects dissipate, and the substrate may be considered optically thick. A numerical model has been developed to examine partial transparency effects, and to compare lightly doped (partially transparent) and heavily doped (opaque) silicon wafers with a multilayer film structure during RTP.

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Thermal-Radiation Absorption Characteristics of Patterned Wafers During Rapid Thermal Processing

MRS Proceedings ◽

10.1557/proc-342-395 ◽

1994 ◽

Vol 342 ◽

Cited By ~ 5

Author(s):

Peter Y. Wong ◽

Ioannis N. Miaoulis

Keyword(s):

Thermal Processing ◽

Radiation Effects ◽

Spectral Characteristics ◽

Rapid Thermal Processing ◽

Chemical Vapor ◽

Radiative Properties ◽

Radiation Absorption ◽

Transient Effects ◽

Patterned Wafers ◽

Absorption Characteristics

ABSTRACTMicroscale radiation effects are responsible for the dependence of absorption and temperature distributions on the geometry of the layering structures and the spectral characteristics of the heat source. The effect of patterned wafers, which may contain several different structures and materials, on the wafer absorption characteristics are investigated for rapid thermal processing. A numerical model to determine the thermal radiative absorptivity of the wafer for different structures and materials is presented for different heating conditions. The resulting transient effects are determined numerically for different rapid thermal processes. The changes in radiative properties for rapid thermal annealing and chemical vapor deposition are investigated for patterned wafers.

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

MRS Proceedings ◽

10.1557/proc-387-15 ◽

1995 ◽

Vol 387 ◽

Cited By ~ 5

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.

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Dopant diffusion studies and free carrier lifetimes during rapid thermal processing of semiconductors

Materials Science in Semiconductor Processing ◽

10.1016/s1369-8001(98)00041-9 ◽

1998 ◽

Vol 1 (3-4) ◽

pp. 207-218 ◽

Cited By ~ 4

Author(s):

Rajan V. Nagabushnam ◽

Rajiv K. Singh ◽

Sujit Sharan

Keyword(s):

Thermal Processing ◽

Rapid Thermal Processing ◽

Free Carrier ◽

Dopant Diffusion ◽

Carrier Lifetimes ◽

Diffusion Studies

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Microscale Radiation Effects in Multilayer Thin-Film Structures During Rapid Thermal Processing

MRS Proceedings ◽

10.1557/proc-303-217 ◽

1993 ◽

Vol 303 ◽

Cited By ~ 3

Author(s):

Peter Y. Wong ◽

Christopher K. Hess ◽

Ioannis N. Miaoulis

Keyword(s):

Thin Film ◽

Numerical Model ◽

Thermal Processing ◽

Radiation Effects ◽

Rapid Thermal Processing ◽

Chemical Vapor ◽

Film Structure ◽

Transient Temperature ◽

Multilayered Structures ◽

Temperature Distributions

ABSTRACTThe individual film thicknesses of multilayered structures processed by rapid thermal processing are of the same order as the wavelengths of the incident radiation. This induces optical interference effects which are responsible for the strong dependency of surface reflectivity, emissivity, and temperature distributions on the geometry of the layering structures, presence of patterns, and thickness of the films. A two-dimensional, finitedifference numerical model has been developed to investigate this microscale radiation phenomena and identify the critical processing parameters which affect rapid thermal processing of multilayer thin films. The uniformity of temperature distributions throughout the wafer during rapid thermal processing is directly affected by incident heater configurations, ramping conditions, wafer-edge effects, and thin-film layering structure. Results from the numerical model for various film structures are presented for chemical vapor deposition of polycrystalline silicon over oxide films on substrate. A novel technique using an edge-enhanced wafer which has a different film structure near its edge is presented as a control over the transient temperature distribution.

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Photon effect on radiative properties of silicon during rapid thermal processing

Journal of Applied Physics ◽

10.1063/1.365780 ◽

1997 ◽

Vol 82 (2) ◽

pp. 830-835 ◽

Cited By ~ 5

Author(s):

G. Chen ◽

T. Borca-Tasciuc ◽

R. B. Fair

Keyword(s):

Thermal Processing ◽

Rapid Thermal Processing ◽

Radiative Properties

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Simulation of silicon wafers heating during rapid thermal processing using “UBTO 1801” unit

Doklady BGUIR ◽

10.35596/1729-7648-2020-18-7-79-86 ◽

2020 ◽

Vol 18 (7) ◽

pp. 79-86

Author(s):

J. A. Solovjov ◽

V. A. Pilipenko ◽

V. P. Yakovlev

Keyword(s):

Mathematical Model ◽

Silicon Wafer ◽

Thermal Processing ◽

Rapid Thermal Processing ◽

Light Flux ◽

Silicon Wafers ◽

Wafer Surface ◽

Constant Density ◽

Wafer Temperature

The present work is devoted to determination of the dependence of the heating temperature of the silicon wafer on the lamps power and the heating time during rapid thermal processing using “UBTO 1801” unit by irradiating the wafer backside with an incoherent flow of constant density light. As a result, a mathematical model of silicon wafer temperature variation was developed on the basis of the equation of nonstationary thermal conductivity and known temperature dependencies of the thermophysical properties of silicon and the emissivity of aluminum and silver applied to the planar surface of the silicon wafer. For experimental determination of the numerical parameters of the mathematical model, silicon wafers were heated with light single pulse of constant power to the temperature of one of three phase transitions such as aluminum-silicon eutectic formation, aluminum melting and silver melting. The time of phase transition formation on the wafer surface during rapid thermal processing was fixed by pyrometric method. In accordance with the developed mathematical model, we determined the conversion coefficient of the lamps electric power to the light flux power density with the numerical value of 5.16∙10-3 cm-2 . Increasing the lamps power from 690 to 2740 W leads to an increase in the silicon wafer temperature during rapid thermal processing from 550°to 930°K, respectively. With that, the wafer temperature prediction error in compliance with developed mathematical model makes less than 2.3 %. The work results can be used when developing new procedures of rapid thermal processing for silicon wafers.

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The Role of Thermal Radiative Properties of Semiconductor Wafers in Rapid Thermal Processing

MRS Proceedings ◽

10.1557/proc-429-3 ◽

1996 ◽

Vol 429 ◽

Cited By ~ 12

Author(s):

P. J. Timans

Keyword(s):

Thermal Processing ◽

Radiation Heat Transfer ◽

Rapid Thermal Processing ◽

Device Fabrication ◽

Radiative Properties ◽

Thermal Radiative Properties ◽

Wide Range ◽

Basic Physics ◽

Key Issues

AbstractRapid thermal processing (RTP) has become a key technology in the fabrication of advanced semiconductor devices. As RTP becomes the accepted technique for an increasingly wide range of processes in device fabrication, the understanding of the basic physics of radiation heat transfer in RTP systems is also being extended rapidly. This paper illustrates the use of optical models for prediction of the thermal radiative properties of semiconductor wafers. Such calculations can be used to address many of the key issues of interest in RTP, including questions concerning temperature measurement and process repeatability.

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The Effect of Multilayer Patterns on Thermal Stress During Rapid Thermal Processing

MRS Proceedings ◽

10.1557/proc-429-43 ◽

1996 ◽

Vol 429 ◽

Cited By ~ 1

Author(s):

Jeffrey P. Hebbi ◽

Klavs F. Jensen

Keyword(s):

Plastic Deformation ◽

Thermal Stress ◽

Thermal Processing ◽

Rapid Thermal Processing ◽

Processing Parameters ◽

Radiative Properties ◽

Stress Fields ◽

Transport Models ◽

Patterned Wafers ◽

Side Illumination

AbstractMultilayer patterns can lead to temperature non-uniformity and undesirable levels of thermal stress in silicon wafers during rapid thermal processing (RTP). Thermal stress can, in turn, cause problems such as photolithography overlay errors and degraded device performance through plastic deformation. In this work, the temperature and stress fields in patterned wafers are simulated using detailed finite-element based reactor transport models coupled with electromagnetic theory for predicting radiative properties of multilayers. The temperature distributions are then used to predict the stress fields in the wafer and the onset of plastic deformation. Results are presented for two generic two-dimensional axi-symmetric reactors employing single and double side illumination. The effect of patterns and processing parameters are explored, and strategies for avoiding pattern induced plastic deformation are evaluated.

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