Laser-Plasma Deposition of Silicon Carbonitride Films by the HMDS Vapor Gas Flow Activation after a Laser Beam Focus

Atmospheric pressure plasma (APP) deposition techniques are useful today because of their simplicity and their time and cost savings, particularly for growth of oxide films. Among the oxide materials, titanium dioxide (TiO2) has a wide range of applications in electronics, solar cells, and photocatalysis, which has made it an extremely popular research topic for decades. Here, we provide an overview of non-thermal APP deposition techniques for TiO2 thin film, some historical background, and some very recent findings and developments. First, we define non-thermal plasma, and then we describe the advantages of APP deposition. In addition, we explain the importance of TiO2 and then describe briefly the three deposition techniques used to date. We also compare the structural, electronic, and optical properties of TiO2 films deposited by different APP methods. Lastly, we examine the status of current research related to the effects of such deposition parameters as plasma power, feed gas, bias voltage, gas flow rate, and substrate temperature on the deposition rate, crystal phase, and other film properties. The examples given cover the most common APP deposition techniques for TiO2 growth to understand their advantages for specific applications. In addition, we discuss the important challenges that APP deposition is facing in this rapidly growing field.

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Ultrafast carbothermal reduction of silica to silicon using a CO2 laser beam

Scientific Reports ◽

10.1038/s41598-020-78562-1 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Seok-Ho Maeng ◽

Hakju Lee ◽

Min Soo Park ◽

Suhyun Park ◽

Jaeki Jeong ◽

...

Keyword(s):

Carbon Black ◽

Laser Beam ◽

Carbothermal Reduction ◽

Gas Flow ◽

Crystalline Silicon ◽

Reduction Process ◽

Reaction Chamber ◽

Raman Shift ◽

Influence Of Process Parameters ◽

Laser Beam Intensity

AbstractWe report the extraction of silicon via a carbothermal reduction process using a CO2 laser beam as a heat source. The surface of a mixture of silica and carbon black powder became brown after laser beam irradiation for a few tens of seconds, and clear peaks of crystalline silicon were observed by Raman shift measurements, confirming the successful carbothermal reduction of silica. The influence of process parameters, including the laser beam intensity, radiation time, nitrogen gas flow in a reaction chamber, and the molar ratios of silica/carbon black of the mixture, on the carbothermal reduction process is explained in detail.

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A Model for Silicon Dendrite Growth During Laser/Plasma Deposition from a Silane Discharge

MRS Proceedings ◽

10.1557/proc-75-755 ◽

1986 ◽

Vol 75 ◽

Author(s):

Harold M. Anderson ◽

Philip J. Hargis

Keyword(s):

Laser Plasma ◽

Plasma Deposition ◽

Dendritic Structure ◽

Negative Temperature ◽

Supercooled Liquid ◽

Interface Temperature ◽

Laser Fluences ◽

Krf Laser ◽

Si Films ◽

Tip Radius

AbstractA model for dendrite growths in polycrystalline Si films formed during laser/plasma deposition with a silane discharge and a pulsed KrF laser has been developed. The model assumes a thin (less than 10 nm) amorphous silicon (a-Si) film is deposited on a substrate prior to phase transformation due to laser heating. The observed dendritic structure of the overall polycrystalline Si films is attributed to Si crystals shooting from an excessively supercooled Si liquid bath. Supercooled liquid forms since the melting point for a-Si can be reached at relatively low KrF laser fluences. Latent heat evolved at the solid-liquid interface induces an interface temperature higher than that of the melt and the requisite negative temperature gradient for absolute bath supercooling. Since the formation of an undercooled liquid by fast melting a-Si is also an important first step in explosive crystal regrowth studies, these results may have important implications for crystal growth and transient annealing. A conical approximation model is used in this study to characterize the stability of the dendrite tip in terms of local temperature gradients, i.e., the degree of undercooling at the tip of the parabolic dendrite. The degree of undercooling and hence the tip radius appears to be significantly affected by small changes in the laser fluence. Stability criteria lead to a relationship between regrowth velocity, V, and the tip radius, R, of the form VR2= constant. The size and stability of the dendrite tip is determined from a balance between the destabilizing force due to thermal diffusion and the stabilizing capillary force. Based on the observed tip radii formed at laser fluences from 0.13 to 0.25 J/cm2, the model predicts regrowth velocities in a range between 2.0 and 20 m/s – values consistent with transient annealing studies of a-Si

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Growth Mechanism and Film Properties in Pulsed Laser-Plasma Deposition

MRS Proceedings ◽

10.1557/proc-236-417 ◽

1991 ◽

Vol 236 ◽

Author(s):

S. Metev ◽

K. Meteva

Keyword(s):

Laser Plasma ◽

Growth Process ◽

Plasma Deposition ◽

Pulsed Laser ◽

Deposition Process ◽

Experimental Investigations ◽

Direct Relation ◽

Film Properties ◽

Experimental Conditions ◽

Laser Flux

AbstractIn the paper the results of a theoretical investigation of the growth process of laser-plasma deposited thin films are discussed. A kinetic approach has been used to establish direct relation between experimental conditions (laser flux density, substrate temperature) and film properties (thickness, structure). The results of some experimental investigations of the deposition process are presented confirming the general conclusions of the developed theoretical model.

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Experimental study of laser beam transmission and power accounting in a large scale length laser plasma

Physics of Plasmas ◽

10.1063/1.874218 ◽

2000 ◽

Vol 7 (8) ◽

pp. 3388-3398 ◽

Cited By ~ 8

Author(s):

J. D. Moody ◽

B. J. MacGowan ◽

R. L. Berger ◽

K. G. Estabrook ◽

S. H. Glenzer ◽

...

Keyword(s):

Experimental Study ◽

Laser Beam ◽

Laser Plasma ◽

Large Scale ◽

Beam Transmission ◽

Scale Length

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Visualization of Shielding Gas Flow and Laser Beam Refraction Zone during CO2 Laser Welding.

The Review of Laser Engineering ◽

10.2184/lsj.27.845 ◽

1999 ◽

Vol 27 (12) ◽

pp. 845-849

Author(s):

Kunimitsu TAKAHASHI ◽

Shunichi SATO

Keyword(s):

Laser Beam ◽

Laser Welding ◽

Co2 Laser ◽

Gas Flow ◽

Shielding Gas

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TERESA Target Area at ELI Beamlines

Quantum Beam Science ◽

10.3390/qubs4040037 ◽

2020 ◽

Vol 4 (4) ◽

pp. 37

Author(s):

Maksym Tryus ◽

Filip Grepl ◽

Timofej Chagovets ◽

Andriy Velyhan ◽

Lorenzo Giuffrida ◽

...

Keyword(s):

Laser Beam ◽

Control Systems ◽

Laser Plasma ◽

Plasma Diagnostics ◽

High Repetition Rate ◽

Target Area ◽

Beam Transport ◽

High Repetition ◽

And Control ◽

Accelerated Particles

The TERESA (TEstbed for high REpetition-rate Sources of Accelerated particles) target area, recently commissioned with the L3-HAPLS laser at Extreme Light Infrastructure (ELI)-Beamlines, is presented. Its key technological sections (vacuum and control systems, laser parameters and laser beam transport up to the target) are described, along with an overview of the available plasma diagnostics and targetry, tested at relativistic laser intensities. Perspectives of the TERESA laser–plasma experimental area at ELI-Beamlines are briefly discussed.

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