Thermal Fields Simulation of the Refining Process for Si Wafer by Continuous-Wave Laser Irradiation

The direct removal of metal impurity from Si wafer by continuous-wave (CW) laser irradiation has been studied. The wafer was irradiated by linear (Nd:YAG) CW laser with a wavelength of 1064nm. The irradiated region of the wafer experienced melting and subsequent recrystallization process during the laser heating and cooling processes. This leads to the redistribution of the metal impurity along the depth direction. The depth profile of metal atoms in Si was measured by secondary ion mass spectrometry (SIMS). The concentration of the metal ions in the CW laser irradiated sample was dramatically decreased at the measurement range of SIMS. Thermal fields of Si wafer irradiated by CW-laser were numerically simulated to explain the SIMS results. A finite element method with a two-dimensional model was selected in the simulation process. The depth of the maximum temperature for the laser irradiated wafer in the irradiation process was related to many parameters, such as, the energy density of the laser and the velocity of the sample moving. The simulation results agree well with our experiment results.

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Laser Timing Probe with Frequency Mapping for Locating Signal Maxima

ISTFA 2009: Conference Proceedings from the 35th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2009p0033 ◽

2009 ◽

Author(s):

L.S. Koh ◽

H. Marks ◽

L.K. Ross ◽

C.M. Chua ◽

J.C.H. Phang

Keyword(s):

Response Time ◽

Continuous Wave ◽

Single Point ◽

Point Measurement ◽

Cw Laser ◽

Measurement Capabilities

Abstract A Laser Timing Probe (LTP) system which uses a noninvasive 1.3 µm continuous wave (CW) laser with frequency mapping and single point measurement capabilities is described. The frequency mapping modes facilitate the localization of signal maxima for subsequent single point measurements. Measurements of waveforms with long delays and 50 ps response time from NMOS and PMOS transistors are also shown.

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Thin-Film Processing of Polypropylene and Polystyrene Sheets by a Continuous Wave CO2 Laser with the Cu Cooling Base

Polymers ◽

10.3390/polym13091448 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1448

Author(s):

Nobukazu Kameyama ◽

Hiroki Yoshida ◽

Hitoshi Fukagawa ◽

Kotaro Yamada ◽

Mitsutaka Fukuda

Keyword(s):

Thin Film ◽

Co2 Laser ◽

Continuous Wave ◽

Cw Laser ◽

Heat Effects ◽

Film Processing ◽

Carbon Dioxide Co2 ◽

A Minor ◽

Residual Heat ◽

Thin Film Processing

Carbon dioxide (CO2) laser is widely used in commercial and industrial fields to process various materials including polymers, most of which have high absorptivity in infrared spectrum. Thin-film processing by the continuous wave (CW) laser is difficult since polymers are deformed and damaged by the residual heat. We developed the new method to make polypropylene (PP) and polystyrene (PS) sheets thin. The sheets are pressed to a Cu base by extracting air between the sheets and the base during laser processing. It realizes to cut the sheets to around 50 µm thick with less heat effects on the backside which are inevitable for thermal processing using the CW laser. It is considered that the boundary between the sheets and the base is in thermal equilibrium and the base prevents the sheets from deforming to support the backside. The method is applicable to practical use since it does not need any complex controls and is easy to install to an existing equipment with a minor change of the stage.

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Optical properties of benzene and derivatives by the single beam thermal lens technique

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s0218863517500254 ◽

2017 ◽

Vol 26 (02) ◽

pp. 1750025 ◽

Cited By ~ 1

Author(s):

M. K. Biswas ◽

P. K. Das ◽

E. Hoque ◽

S. M. Sharafuddin ◽

S. K. Das ◽

...

Keyword(s):

Thermal Lens ◽

Continuous Wave ◽

Refractive Index Change ◽

Optical Nonlinearity ◽

Index Change ◽

Single Beam ◽

Cw Laser ◽

Ion Laser ◽

Benzene Toluene ◽

Long Pulse

The present work studies the optical nonlinearity exhibited by the material (for Continuous Wave (CW) laser or long pulse) due to the change in thermal properties of the material on illumination. Thermal lens (TL) technique has been used to measure the refractive index change due to the formation of TL along with other thermo-optic properties of the material in solution. A CW Ar-ion laser has been used as light source and the laser beam was chopped at 25[Formula: see text]Hz frequency to obtain 12[Formula: see text]ms pulse to observe the formation of the TL within the sample. The [Formula: see text] value have been calculated by the TL technique for Benzene, Toluene and Dimethylaniline (DMA) in toluene and Benzene. The [Formula: see text] value is found to be in the order of 10[Formula: see text] to 10[Formula: see text][Formula: see text]cm2[Formula: see text]W[Formula: see text].

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Mechanism of microlens formation in quantum dot glasses under continuous-wave laser irradiation

Journal of Applied Physics ◽

10.1063/1.1373704 ◽

2001 ◽

Vol 89 (12) ◽

pp. 8273-8278 ◽

Cited By ~ 16

Author(s):

Yuri Kaganovskii ◽

Irena Antonov ◽

Fredrick Bass ◽

Michael Rosenbluh ◽

Audrey Lipovskii

Keyword(s):

Quantum Dot ◽

Laser Irradiation ◽

Continuous Wave ◽

Continuous Wave Laser ◽

Wave Laser

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Design and Fabrication of a Magnetocaloric Microcooler

Microelectromechanical Systems ◽

10.1115/imece2005-82720 ◽

2005 ◽

Cited By ~ 1

Author(s):

Sangchae Kim ◽

Bharath Bethala ◽

Simone Ghirlanda ◽

Senthil N. Sambandam ◽

Shekhar Bhansali

Keyword(s):

Magnetic Field ◽

Ambient Temperature ◽

Temperature Change ◽

Entropy Change ◽

Temperature Sensors ◽

Experimental Results ◽

Maximum Temperature ◽

Alternative Technology ◽

Temperature Conditions ◽

Si Wafer

Magnetocaloric refrigeration is increasingly being explored as an alternative technology for cooling. This paper presents the design and fabrication of a micromachined magnetocaloric cooler. The cooler consists of fluidic microchannels (in a Si wafer), diffused temperature sensors, and a Gd5(Si2Ge2) magnetocaloric refrigeration element. A magnetic field of 1.5 T is applied using an electromagnet to change the entropy of the magnetocaloric element for different ambient temperature conditions ranging from 258 K to 280 K, and the results are discussed. The tests show a maximum temperature change of 7 K on the magnetocaloric element at 258 K. The experimental results co-relate well with the entropy change of the material.

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Enhancement of pulsed laser ablation assisted with continuous wave laser irradiation

Science China Physics Mechanics and Astronomy ◽

10.1007/s11433-018-9288-1 ◽

2018 ◽

Vol 62 (3) ◽

Cited By ~ 5

Author(s):

Ye Ding ◽

LiJun Yang ◽

MingHui Hong

Keyword(s):

Laser Ablation ◽

Laser Irradiation ◽

Continuous Wave ◽

Pulsed Laser ◽

Pulsed Laser Ablation ◽

Continuous Wave Laser ◽

Wave Laser

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Research on influence of parasitic resistance of InGaAs solar cells under continuous wave laser irradiation

Journal of Physics Conference Series ◽

10.1088/1742-6596/844/1/012014 ◽

2017 ◽

Vol 844 ◽

pp. 012014 ◽

Cited By ~ 1

Author(s):

Guangji Li ◽

Hongchao Zhang ◽

Guanglong Zhou ◽

Jian Lu ◽

Dayong Zhou

Keyword(s):

Solar Cells ◽

Laser Irradiation ◽

Continuous Wave ◽

Continuous Wave Laser ◽

Parasitic Resistance ◽

Wave Laser

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Threshold of permanent cornea thermal damage due to incidental continuous wave CO2 laser irradiation

Thermal Science ◽

10.2298/tsci1002459t ◽

2010 ◽

Vol 14 (2) ◽

pp. 459-467 ◽

Cited By ~ 1

Author(s):

Mayada Tahir

Keyword(s):

Laser Irradiation ◽

Co2 Laser ◽

Thermal Damage ◽

Continuous Wave ◽

Anterior Part ◽

Outer Part ◽

Human Cornea ◽

Thermal Dose ◽

Element Analysis ◽

Reflex Blink

Cornea thermal damage due to incidental continuous wave CO2 laser irradiation is studied numerically based on bio-heat equation. The interaction of laser with tissue leads to a rapid temperature increased in target and the nearby tissue. As the temperature of the eye surface reaches 44?C, a sensation of pain will cause aversion response of the reflex blink and/or shifting away from the source of pain. The aim of the work is to predict numerically the threshold limit of incidental laser power that causes damage to the anterior part of the cornea, which can be healed within 2-5 days as long as damage is not exceeding the outer part of the eye (epithelium). A finite element analysis is used to predict temperature distribution through the cornea where the necroses region can be obtained using thermal dose equation. The thermal dose that required for damaging the cornea is predicted from previously published experimental data on rhesus monkeys and used later as a limit for shrinkage to human cornea. The result of this work is compared by international standard of safety and a good nearby result is obtained which verified the result of this work.

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