Growth rate of liquid drops on a flat surface during dropwise condensation of vapor from a vapor-gas mixture

The effect of argon content upon the growth rate and the properties of diamond thin films grown with different grains sizes are explored. An argon-free and argon-rich gas mixture of methane and hydrogen is used in a hot filament chemical vapor deposition reactor. Characterization of the films is accomplished by scanning electron microscopy, Raman spectroscopy and high-resolution x-ray diffraction. An extensive comparison of the growth rate values and films morphologies obtained in this study with those found in the literature suggests that there are distinct common trends for microcrystalline and nanocrystalline diamond growth, despite a large variation in the gas mixture composition. Included is a discussion of the possible reasons for these observations.

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Coalescence Characteristics of Liquid Drops with Application to Dropwise Condensation

Energy, Environment, and Sustainability - Applications Paradigms of Droplet and Spray Transport: Paradigms and Applications ◽

10.1007/978-981-10-7233-8_7 ◽

2017 ◽

pp. 165-200

Author(s):

Praveen M. Somwanshi ◽

K. Muralidhar ◽

Sameer Khandekar

Keyword(s):

Dropwise Condensation ◽

Liquid Drops

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Growth and Evaluation of [AFeOx/REFeO3] (A=Ca, Sr, RE=La, Bi) Superlattices by Pulsed Laser Deposition Method Using High Density Targets Prepared by Pechini Method

MRS Proceedings ◽

10.1557/opl.2012.1235 ◽

2012 ◽

Vol 1454 ◽

pp. 161-166 ◽

Cited By ~ 1

Author(s):

Nobuyuki Iwata ◽

Yuta Watabe ◽

Yoshito Tsuchiya ◽

Kento. Norota ◽

Takuya Hashimoto ◽

...

Keyword(s):

Growth Rate ◽

Flat Surface ◽

Pechini Method ◽

Laser Deposition ◽

Growth Constant ◽

Constant Growth Rate ◽

X Ray ◽

Flat Interface ◽

Reference Layer ◽

Constant Growth

ABSTRACTThe LaFeO3 and CaFeOX layers are grown using highly dense target prepared by Pechini method, with which accurate growth rate is achieved. Since the LaFeO3demonstrates the obvious RHEED oscillation until the end of growth, constant growth rate, and the step-terraces structure, the LFO is employed as a buffer and/or reference layer to determine the required pulses to deposit the thickness we desire in the superlattice. Superlattices show the clear satellite peaks and Laue oscillation in the XRD spectra as well as the oscillations caused by the film thickness with a flat surface and superstructure with a flat interface in the x-ray reflection spectrum. The streaky RHEED patterns and step-terraces surface are consistent with the results of spectra using x-ray.

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Effect of liquid drops on the thermal explosion of a gas mixture

Symposium (International) on Combustion ◽

10.1016/s0082-0784(96)80378-x ◽

1996 ◽

Vol 26 (1) ◽

pp. 1557-1563 ◽

Cited By ~ 6

Author(s):

Vladimir Goldshtein ◽

Igor Goldfarb ◽

Ann inoviev ◽

Isaac Shreiber

Keyword(s):

Thermal Explosion ◽

Gas Mixture ◽

Liquid Drops

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The Effect of Carrier Gas and Reactor Pressure on Gallium Nitride Growth in MOCVD Manufacturing Process

Journal of Heat Transfer ◽

10.1115/1.4043895 ◽

2019 ◽

Vol 141 (8) ◽

Cited By ~ 1

Author(s):

Omar Jumaah ◽

Yogesh Jaluria

Keyword(s):

Thin Films ◽

Growth Rate ◽

Gallium Nitride ◽

Chemical Vapor ◽

Wide Band ◽

Rotating Disk ◽

Organic Chemical ◽

Gas Mixture ◽

Carrier Gas ◽

Reactor Pressure

Gallium nitride (GaN) is an attractive material for manufacturing light emitting diodes and other electronic devices due to its wide band-gap and superb optoelectronic performance. The quality of GaN thin film determines the reliability and durability of these devices. Metal-organic chemical vapor deposition (MOCVD) is a common technique used to fabricate high-quality GaN thin films. In this paper, GaN growth rate and uniformity in a vertical rotating disk MOCVD reactor are investigated on the basis of a three-dimensional computational fluid dynamics (CFD) model. GaN growth rate is investigated under the influence of reactor pressure, precursor concentration ratio, and composition of the carrier gas mixture. The numerical simulation shows that the carrier gas mixture and the reactor pressure have significant effects on growth rate and uniformity of GaN thin films. It is also found that an appropriate mixture of N2 and H2 may be employed as the carrier gas to improve the flow field characteristic in the reactor. This results in an improved crystal growth of GaN thin films.

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Microstructures of Chemical-Vapour-Deposited Tin Films

MRS Proceedings ◽

10.1557/proc-343-741 ◽

1994 ◽

Vol 343 ◽

Author(s):

Noboru Yoshikawa ◽

Atsushi Kikuchi

Keyword(s):

Growth Rate ◽

High Temperature ◽

Film Growth ◽

Chemical Vapour ◽

Axial Direction ◽

Steel Tube ◽

Gas Mixture ◽

Tin Films ◽

Local Deposition ◽

Deposition Conditions

ABSTRACTA gas mixture consisting of TiCl4, H2 and N2 was fed into an externally-heated steel tube, and TiN was deposited on the inner wall by CVD. Microstuctures of the films were observed and their relationships with the preferred crystal orientations were studied. Distributions of the film growth rate and gas concentrations along the axial direction were calculated.By comparing the film microstructures with the calculated local deposition conditions, it is shown that formation of the films with (110) preferred orientation correlated with the conditions at high temperature and low partial pressure of TiCl4 on the substrate.

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Plasma-Enhanced Atomic Layer Deposition of GaN Thin Film at Low Temperature

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.727.907 ◽

2017 ◽

Vol 727 ◽

pp. 907-914

Author(s):

Wen Hui Tang ◽

Yi Jia ◽

Bo Cheng Zhang ◽

Chang Wei Yang ◽

You Zhi Qu ◽

...

Keyword(s):

Thin Films ◽

Growth Rate ◽

Low Temperature ◽

Atomic Layer Deposition ◽

Flow Rate ◽

Nitrogen Sources ◽

Atomic Layer ◽

Gas Mixture ◽

X Ray ◽

Layer Deposition

Polycrystalline GaN thin films were successfully grown at low temperature (250 °C) by plasma-enhanced atomic layer deposition with NH3, N2, N2/H2 gas mixture and trimethylgallium (TMG) as precusor. The growth rate, crystal structure, surface composition and the valence state of the corresponding element of the GaN thin films using different nitrogen sources were characterized and examined systematically via the spectroscopic ellipsometry, the x-ray diffractometer, the x-ray photoel-ectron spectrometer. It is showed that all the GaN thin films using different nitrogen sources were polycrystalline structure and the preffered orientation were mainly (100). The films using N2 and N2/H2 gas mixture had a higher crystal quality than films using NH3. The GPC (growth rate per cycle) would increase with the increase of the N2 flow rate. The films using a suitable ratio of N2/H2 flow rate had not only a high GPC but a good crystal quality. The ratios of Ga/N element of the films using N2/H2 gas mixture were approximated to 1:1, it would increase with the ratio of the N2/H2 flow rate in the gas mixture, which is showing much effect of the ratios of N2/H2 flow rate on the nitrogen content of the thin films.

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Water-air ejector with conical-cylindrical mixing chamber

Acta Polytechnica ◽

10.14311/ap.2021.61.0768 ◽

2021 ◽

Vol 61 (6) ◽

pp. 768-776

Author(s):

Andrii Sliusenko ◽

Vitalii Ponomarenko ◽

Inna Forostiuk

Keyword(s):

Vertical Position ◽

Gas Mixture ◽

Maximum Volume ◽

Entrainment Ratio ◽

Mixture Flow ◽

Liquid Drops ◽

Passive Flow ◽

Mixing Chamber ◽

Air Ejector ◽

The Comparative Study

In the paper, the hydrodynamics of the liquid-gas mixture in the mixing chamber of the ejectors at different spatial positions was analyzed and the comparative study of such ejectors was carried out. It was found that a more ordered mode of movement of the mixture in the mixing chamber is created as a result of the coincidence of the velocity vector of liquid drops and the direction of gravity in the vertical position of the ejectors. This leads to increasing the volume entrainment ratio almost twice. The analysis of the liquid-gas mixture flow in the mixing chamber, evaluation calculations and research allowed to develop and to patent a jet apparatus with a conical-cylindrical (combined) mixing chamber. It was also found that for such ejectors, the volume entrainment ratio is 15–55% higher than for a jet apparatus with a cylindrical mixing chamber due to the reduction of the resistance of the passive flow into the mixing chamber and prevention of the formation of reverse-circulating flows. A study has been conducted on liquid-gas ejectors in the range of the main geometric parameter m (ratio of the mixing chamber area to the nozzle area) 9.4–126.5, which allowed to establish its rational values at which the maximum volume entrainment ratio is achieved (m = 25–40).

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An Analysis of Tungsten FIB-Fabricated Via Resistance

ISTFA 2008: Conference Proceedings from the 34th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2008p0133 ◽

2008 ◽

Author(s):

David W. Niles ◽

Jay Meyer ◽

Ronald W. Kee ◽

Michael DiBattista

Keyword(s):

Growth Rate ◽

Aspect Ratio ◽

Focused Ion Beam ◽

Flat Surface ◽

Ion Beam ◽

Effective Area ◽

Flat Surfaces ◽

Least Squares Fit ◽

Resistance Model ◽

Resistance Data

Abstract We present an analysis of tungsten vias fabricated by a focused ion beam with regard to the understanding of circuit editing strategies. The growth rate of W is ~10 times faster in high aspect ratio vias than on flat surfaces, and W in vias has 4 at. % more C but only one-tenth the Ga of surface-deposited W. We propose that vias act like small Faraday cups, trapping the energy of the Ga+ ions and the reaction byproducts to enhance the growth rate of W and to increase the C to W ratio in vias compared to flat surfaces. The resistivity of W in the vias determined by a least squares fit to resistance data is 250μΩ-cm, unchanged from the resistivity of W deposited on a flat surface. The resistances of the vias fabricated in a SiO2 layer to contact an underlying Al sheet layer fit well to either of two models: 1) an effective area model that invokes resistive via sidewalls that do not participate in conduction, and 2) an contact resistance model that invokes tapered vias with a constricted W/Al contact area.

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Solution Growth of p-Type 4H-SiC Bulk Crystals with Low Resistivity

Materials Science Forum ◽

10.4028/www.scientific.net/msf.778-780.75 ◽

2014 ◽

Vol 778-780 ◽

pp. 75-78 ◽

Cited By ~ 9

Author(s):

Takayuki Shirai ◽

Katsunori Danno ◽

Akinori Seki ◽

Hidemitsu Sakamoto ◽

Takeshi Bessho

Keyword(s):

Growth Rate ◽

Flat Surface ◽

Low Cost ◽

High Growth ◽

High Growth Rate ◽

Solution Growth ◽

Bulk Crystals ◽

Low Resistivity ◽

Al Content ◽

P Type

P-type 4H-SiC bulk crystals have been grown at a high growth rate of 1.0 mm/h by solution growth using Si-Cr-Al based melt. The crystals grown from solution with an Al content of 10at% show low resistivity of 35 mcm, which is two orders of magnitude lower than commercialwafers (Resistivity: 2500 mcm). The low-resistivity crystals have flat surface and few solvent inclusions. These results indicate that solution growth is a suitable method for fabricating low-resistivity p-type substrates with low cost.

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