Temperature Characterization of Pulsed Laser Annealing of Semiconductors

1983 ◽  
Vol 13 ◽  
Author(s):  
D.L. Kwong ◽  
D.M. Kim
Keyword(s):  
Laser Beam ◽  
Laser Annealing ◽  
Coupling Effect ◽  
Pulsed Laser ◽  
Heat Diffusion ◽  
Optical Absorption Coefficient ◽  
Analytic Description ◽  
Transient Heating ◽  
Heat Diffusion Equation ◽  
Wide Range

ABSTRACTThe dynamic characteristics of lattice temperature, T attained in Si under the influence of a high power laser beam irradiation are examined analytically over a wide range of laser wavelengths, pulse intensities and durations. The strongly temperature-dependent material parameters, such as optical absorption coefficient α(T) and thermal diffusivity D(T) are incorporated in heat diffusion equation, and their nonlinear coupling effect on the ensuing temperature in laser-processed semiconductors are examined. Specifically, the threshold pulse energy for surface melting is characterized as a function of both material and annealing laser beam parameters. This analytic description of pulsed laser heating of semiconductors should provide considerable insight into the transient heating phenomena and localized material modifications.

Modeling of Titanium Oxide Layer Growth Produced by Fiber Laser Beam

2013 ◽  
Vol 336 ◽  
pp. 11-18 ◽  
Author(s):  
Farida Hamadi ◽  
El Hachemi Amara ◽  
Djamila Bennaceur-Doumaz ◽  
R. Boutaka ◽  
H. Kellou ◽  
...  
Keyword(s):  
Temperature Field ◽  
Laser Beam ◽  
Film Growth ◽  
Three Dimensional ◽  
Layer Growth ◽  
Heat Diffusion ◽  
Metallic Surface ◽  
Heat Diffusion Equation ◽  
Computational Procedures ◽  
Volume Method

In this paper, we study the oxidation process during the heating of a titanium metallic surface by a Nd-YAG fiber pulsed laser beam under air environment. For this, we adopted an approach that considers a three-dimensional heat diffusion model coupled with an oxidation parabolic law (oxidation kinetics). The heat diffusion equation solved numerically, gives the temperature field. The oxide film growth is simulated by implementing a dynamic mesh technique. We developed computational procedures UDFs (User Defined Function) running interactively with the Fluent fluid dynamics software [ that implements the finite volume method. These UDFs are developed to insert the oxidation law, the temperature field, the specific boundary conditions and the mesh deformation into the calculation.

scholarly journals Thermal Influence Analysis of Coatings and Contact Resistance in Turning Cutting Tool using Comsol

2021 ◽  
Author(s):  
Carlos Adriano Ribeiro ◽  
João Roberto Ferreira ◽  
Sandro Metrevelle Marcondes Lima e Silva
Keyword(s):  
Contact Resistance ◽  
Cutting Tools ◽  
Heat Diffusion ◽  
The Finite Element Method ◽  
Machining Processes ◽  
Transient Heating ◽  
Heat Diffusion Equation ◽  
Tool Holder ◽  
Thermal Influence ◽  
Cutting Speeds

Abstract In machining processes, cutting tools reach temperatures higher than 900ºC, thus deteriorating their mechanical properties. To reduce this problem, cutting tools are coated with materials possessing thermal insulation characteristics. Such coatings benefit machining, providing faster cutting speeds and tools life. However, the heating of the tools is still present. Therefore, this work simulates the transient heating phenomenon of a tool and its tool holder, considering the presence of the coating. The effects of convection, radiation, and contact resistance between the tool and the tool holder are also considered. The thermophysical properties of the tool elements depend on temperature. Experimental measurements of parameters related to contact resistance were carried out to make the thermal model closer to real situations. The COMSOL program was used to solve the heat diffusion equation using the Finite Element Method. Comparisons of calculated temperatures are presented for the uncoated (substrate only) and coated inserts with aluminum oxide (Al2O3) and titanium nitride (TiN), respectively. Finally, the results and the consequences of the assembly parameters in the fields of temperature and contact resistance are discussed.

First and Second Order Raman Studies of Composition and Structural Ordering in Hg1−xCdxTe

1989 ◽  
Vol 161 ◽  
Author(s):  
A. Compaan ◽  
R. C. Bowman
Keyword(s):  
Laser Annealing ◽  
Cluster Formation ◽  
Pulsed Laser ◽  
Second Order ◽  
Bulk Growth ◽  
Resonance Behavior ◽  
Pulsed Laser Annealing ◽  
Wide Range ◽  
Laser Anneal ◽  
Defect Densities

ABSTRACTThe effects of alloy fluctuations, defect densities, and short-range clustering on the resonance behavior of first and second order LO and TO Raman scattering are studied in Hg1−xCdxTe (MCT). X-values between 0.20 and 0.32 and photon energies from 2.35 to 2.7 eV were used with samples prepared by a wide range of techniques--LPE, MOCVD, MBE, bulk growth, and pulsed laser annealing. We examine the resonance behavior of the HgTe-like TO mode at ∼120 cm−1 and the mode at 133 cm−1, which has been identified as originating from the preferential clustering of 3 Hg and 1 Cd about the Te. We find that the intensity of this peak for various bulk and epitaxially grown samples is unusually large only near the E, resonance. Pulsed laser annealing with a Nd:YAG-pumped dye laser strongly suppresses this mode in all samples suggesting that extremely rapid epitaxial regrowth may inhibit the 3:1 cluster formation. In addition, the resonance-enhanced LO overtones are suppressed by the pulsed laser anneal.

Raman Studies of Carrier Activation in Laser Annealed GaAs Capped with Silicon Nitride

1986 ◽  
Vol 74 ◽  
Author(s):  
A. Compaan ◽  
S. C. Abbi ◽  
H. D. Yao ◽  
A. Bhat ◽  
F. Hashmi
Keyword(s):  
Silicon Nitride ◽  
Laser Pulse ◽  
Raman Scattering ◽  
Excimer Laser ◽  
Laser Annealing ◽  
Pulsed Laser ◽  
Dye Laser ◽  
Pulsed Laser Annealing ◽  
Wide Range ◽  
Xecl Excimer Laser

AbstractCarrier concentrations exceeding 1019/cm3 in GaAs implanted with Si (2 × 1014/cm2 @ 140 keV) have been obtained by pulsed laser annealing with either a dye laser (λ = 728 nm) or a XeCl excimer laser (λ = 308 nm). Carrier concentrations were measured by plasmon Raman scattering over a wide range of anneal energy densities. Compared with capless laser annealing, much higher carrier activations were achieved when the annealing laser pulse was incident through a Si3N4 cap.

scholarly journals Comparative analysis of elementary and edge-preserving spatial filters in noise removal – a comprehensive study

2021 ◽  
Vol 23 (06) ◽  
pp. 1244-1251
Author(s):  
K. Sivakumar ◽  
◽  
Sakthiraam. B ◽  
Santosh Snehal. V ◽  
Yogashivasankarri. S ◽  
...  
Keyword(s):  
Stereo Matching ◽  
Noise Removal ◽  
Heat Diffusion ◽  
Spatial Filters ◽  
Edge Preserving ◽  
Heat Diffusion Equation ◽  
Style Transfer ◽  
Wide Range ◽  
Realistic Representation ◽  
Anisotropic Diffusion Filters

Preserving the edges and information is one of the main purposes of edge-preserving filters. That is, they’re employed to smooth a picture, and minimize halos, phantoms, and edge blur over the edge. They have a nonlinear relationship between one thing and another. Bilateral filters, anisotropic diffusion filters, directed filters, and trilateral filters are all types of example filters. The filter family may be used in a wide range of image processing tasks, such as denoising, video abstraction, demosaicing, optical flow estimation, stereo matching, tone mapping, style transfer, relighting, and others. The paper gives a clear description of edge-preserving filters, from the heat diffusion equation in ancient times to the present, explaining their numerous applications and detailing their numerous uses. Additionally, mathematical analysis is included, as well as efficient and optimized implementations. The focus is on preserving the boundaries, spikes, and canyons, and the information is given clearly and in detail. Finally, it offers a realistic representation of efficient implementation, as well as a comprehensive research scope for future hardware implementation.

PULSED LASER DEPOSITION — ABLATION MECHANISM AND APPLICATIONS

2013 ◽  
Vol 22 ◽  
pp. 355-360 ◽  
Author(s):  
M. C. RAO
Keyword(s):  
High Temperature ◽  
Laser Ablation ◽  
Laser Beam ◽  
Pulsed Laser Deposition ◽  
Continuous Wave ◽  
High Temperature Superconductivity ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Wide Range ◽  
Laser Flux

Laser ablation is the process of removing material from a solid surface by irradiating it with a laser beam. At low laser flux, the material is heated by the absorbed laser energy and evaporates or sublimates. At high laser flux, the material is typically converted to a plasma. Usually, laser ablation refers to removing material with a pulsed laser, but it is possible to ablate material with a continuous wave laser beam if the laser intensity is high enough. In general, the method of pulsed laser deposition (PLD) is simple. Only few parameters need to be controlled during the process. Targets used in PLD are small compared with other targets used in other sputtering techniques. It is quite easy to produce multi-layer film composed of two or more materials. Besides, by controlling the number of pulses, a fine control of film thickness can be achieved. Pulsed-laser deposition has been used to deposit an extraordinarily wide range of materials. Historically, the most significant application of PLD has been in the area of high temperature superconducting thin films. The demonstration that PLD could be used to deposit YBa2Cu3O7-x (YBCO) films with zero resistivity at nearly 85 K sparked a significant amount of high temperature superconductivity research over the past decade and has stimulated research in PLD in general. The most striking limitations of PLD are the generation of particulates during the deposition process and the non uniform coating thickness, when substrates of large area are deposited.

scholarly journals Simulation of the temperature profile of BaCaZrTiO3 thin films during laser annealing

2020 ◽  
Vol 233 ◽  
pp. 05008
Author(s):  
Tiago Rebelo ◽  
João Alves ◽  
Bernardo Almeida
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Room Temperature ◽  
Laser Annealing ◽  
Laser Intensity ◽  
Structural Phase ◽  
Phase Changes ◽  
Heat Diffusion ◽  
Maximum Temperature ◽  
Heat Diffusion Equation

The laser annealing of a Ba0.85Ca0.15Ti0.9Zr0.1O3 (BCZT) thin film on a metglas substrate was simulated in order to understand how the annealing parameters (energy and fluence of the laser, pulse duration, etc) influence the optimization of the crystallinity of the film. Using a 1D heat diffusion equation combined with a finite difference method, the variation of the temperature with the depth relative to the film’s surface and on annealing time was studied. The laser intensity, BCZT’s reflectivity and the temperature dependence of the ther¬mal conductivity and specific heat of the BCZT were considered. No structural phase changes were detected in both the BCZT and the metglas for the values of laser fluence studied, but for 80 mJ/cm2 the maximum temperature approached near the BCZT’s melting temperature. It was observed that since the film’s ther¬mal conductivity decreases with increasing fluence, lower fluences allow for a better distribution of the laser’s energy throughout the crystal lattice, increasing the crystallinity. It was further observed that between consecutive pulses the film’s temperature stabilizes at room temperature.

Pulsed laser annealing of zinc implanted GaAs

1978 ◽  
Vol 14 (4) ◽  
pp. 85 ◽  
Author(s):  
S.S. Kular ◽  
B.J. Sealy ◽  
K.G. Stephens ◽  
D.R. Chick ◽  
Q.V. Davis ◽  
...  
Keyword(s):  
Laser Annealing ◽  
Pulsed Laser ◽  
Pulsed Laser Annealing

scholarly journals The Al Doping Effect on Epitaxial (In,Mn)As Dilute Magnetic Semiconductors Prepared by Ion Implantation and Pulsed Laser Melting

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4138
Author(s):  
Ye Yuan ◽  
Yufang Xie ◽  
Ning Yuan ◽  
Mao Wang ◽  
René Heller ◽  
...  
Keyword(s):  
Curie Temperature ◽  
Ion Implantation ◽  
Diluted Magnetic Semiconductors ◽  
Laser Annealing ◽  
Magnetic Semiconductors ◽  
Dilute Magnetic Semiconductors ◽  
Pulsed Laser ◽  
Laser Melting ◽  
Co Doping ◽  
Diluted Magnetic

One of the most attractive characteristics of diluted ferromagnetic semiconductors is the possibility to modulate their electronic and ferromagnetic properties, coupled by itinerant holes through various means. A prominent example is the modification of Curie temperature and magnetic anisotropy by ion implantation and pulsed laser melting in III–V diluted magnetic semiconductors. In this study, to the best of our knowledge, we performed, for the first time, the co-doping of (In,Mn)As diluted magnetic semiconductors by Al by co-implantation subsequently combined with a pulsed laser annealing technique. Additionally, the structural and magnetic properties were systematically investigated by gradually raising the Al implantation fluence. Unexpectedly, under a well-preserved epitaxial structure, all samples presented weaken Curie temperature, magnetization, as well as uniaxial magnetic anisotropies when more aluminum was involved. Such a phenomenon is probably due to enhanced carrier localization introduced by Al or the suppression of substitutional Mn atoms.

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