Relation of Heat Transfer with the Growth Rate of InSb based Bulk Crystals Grown by VDS and its Effect on the Crystal Quality

2020 ◽  
Vol 12 (2) ◽  
pp. 02012-1-02012-5
Author(s):  
Dilip Maske ◽  
◽  
Manisha Deshpande ◽  
Dattatray Gadkari ◽  
◽  
...  
Keyword(s):  
Heat Transfer ◽  
Growth Rate ◽  
Crystal Quality ◽  
Bulk Crystals

Bulk Growth Of Silicon Carbide Crystals: Analysis Of Growth Rate And Crystal Quality

1997 ◽  
Vol 483 ◽  
Author(s):  
D. Hofmann ◽  
R. Eckstein ◽  
L. Kadinski ◽  
M. Kölbl ◽  
M. Müller ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Growth Rate ◽  
Defect Formation ◽  
Growth Parameters ◽  
Crystallization Rate ◽  
Crystal Quality ◽  
Process Time ◽  
Process Conditions ◽  
Diffusion And Kinetics ◽  
Axial Heat

AbstractThe process conditions during SiC bulk crystal growth by physical vapor transport (PVT) are studied both theoretically and experimentally focussing on the magnitude of achievable growth rates V and possible correlations with defect formation. An increase of micropipe density with crystallization rate is observed. Growth parameters determining V are identified allowing a general non-dimensional representation of the dependencies of growth rate from kinetics, mass transport and heat transfer. It can be shown that at conventional process conditions of SiC growth by sublimation in graphite environment (5 mbar ≤p≤ 100 mbar, 2400K ≤T≤ 2600K) growth is limited by diffusion and kinetics for very short crystal lengths L and by heat transfer for geometries L> 1 mm. Including possible destabilizing effects due to constitutional supercooling an augmentation of V without deteriorating crystal quality should be conducted by stochiometry control for supression of graphitization and control of the thermal field tailoring the axial heat transfer with process time. Finally SiC growth from the liquid phase is introduced to promise a growth technique for specific SiC material as, in contrast to PVT growth, the closing of micropipes is demonstrated to be feasible.

scholarly journals MOCVD Equipment for Recent Developments towards the Blue and Green Solid State Laser

1996 ◽  
Vol 1 ◽  
Author(s):  
H. Jürgensen ◽  
D. Schmitz ◽  
G. Strauch ◽  
E. Woelk ◽  
M. Dauelsberg ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Growth Rate ◽  
Mass Transport ◽  
Stokes Equations ◽  
Chemical Species ◽  
Heterogeneous Reactions ◽  
Radiative Properties ◽  
Coupled Flow ◽  
Device Structure ◽  
Group Iii

For the growth of an electrically pumped lasing nitride emitter, the development of the MOCVD equipment and the process are mutually dependent. Most important is the implementation of the rapid temperature changes that are required between the growth of the different layers of a device structure. Equally important is to provide a reaction chamber that develops a stable gas phase at all growth temperatures used in the process. In this paper we will give insight in the technology and the relationship between processes and equipment. The development of the reation chamber was supported by mathematical modeling that formed the basis for the selection of appropriate process parameters for growth of group-III nitrides. The modeling consists of the numerical solution of the Navier-Stokes equations coupled with heat transfer and mass transport of the chemical species. The modeling of radiative heat transfer takes into account the effect of changing surface radiative properties. These changes result from the coating of the reactor inner surfaces during the growth run. Coupled flow dynamics and chemistry including homogeneous and heterogeneous reactions play an important role for predicting growth rate distributions on the susceptor area. At the practically used high temperatures, group-III metalorganics turn out to be almost entirely decomposed and it is the mass transport of these decomposition products to the growing layer that is assumed to control the growth rate in accordance with experimental observations.AIXTRON GmbH

Wool growth regulation by local skin cooling

1967 ◽  
Vol 9 (3) ◽  
pp. 393-397 ◽  
Author(s):  
J. M. Doney ◽  
J. G. Griffiths
Keyword(s):  
Heat Transfer ◽  
Growth Rate ◽  
Blood Flow ◽  
Growth Regulation ◽  
Fibre Diameter ◽  
Systemic Response ◽  
Local Cooling ◽  
Local Skin ◽  
Wool Growth ◽  
Skin Cooling

Local cooling of the skin, produced by exposure to wind was shown to depress the rate of length growth of wool. The depression was associated with reductions in skin temperature and blood flow and with increases in heat transfer in the exposed regions. Fibre diameter did not appear to be affected and there were no indications of a systemic response of wool growth rate to exposure.

Bulk Growth of InGaSb Alloy Semiconductor under Terrestrial Conditions: A Preliminary Study for Microgravity Experiments at ISS

2012 ◽  
Vol 323-325 ◽  
pp. 539-544 ◽  
Author(s):  
M. Arivanandhan ◽  
G. Rajesh ◽  
A. Tanaka ◽  
T. Ozawa ◽  
Yasunori Okano ◽  
...  
Keyword(s):  
Growth Rate ◽  
Grown Crystal ◽  
Space Station ◽  
Growth Direction ◽  
Heating Furnace ◽  
Bulk Crystals ◽  
Bulk Growth ◽  
Microgravity Experiments ◽  
Terrestrial Condition ◽  
Preliminary Study

As a preliminary experiment for the growth of InGaSb alloy crystals under microgravity at International Space Station (ISS), bulk crystal was grown under terrestrial condition using the same gradient heating furnace (GHF). Czochralski grown GaSb <111>B single crystal was used as a seed and feed crystals for the growth of InGaSb bulk crystals. During the growth, heat pulses were intentionally introduced periodically to create the growth striations. From the striations, the growth rate of the grown crystal was estimated. The results show that the growth rate was gradually increased from the beginning of the growth and became stable. On the other hand the In composition of the grown crystal decreased along the growth direction. From the In composition, the temperature gradient in the solution was estimated and it was almost the same of that fixed during the growth.

A numerical study on heat transfer and film growth rate of InP and GaAs MOCVD process

2005 ◽  
Vol 276 (3-4) ◽  
pp. 431-438 ◽  
Author(s):  
Ik-Tae Im ◽  
Masakazu Sugiyama ◽  
Yukihiro Shimogaki ◽  
Yoshiyaki Nakano
Keyword(s):  
Heat Transfer ◽  
Growth Rate ◽  
Film Growth ◽  
Numerical Study ◽  
Film Growth Rate

scholarly journals Experiments on ice spikes and a simple growth model

2004 ◽  
Vol 50 (170) ◽  
pp. 375-381 ◽  
Author(s):  
Lesley Hill ◽  
Edward Lozowski ◽  
Russell D. Sampson
Keyword(s):  
Heat Transfer ◽  
Growth Rate ◽  
Heat Transfer Coefficient ◽  
Tap Water ◽  
Mass Conservation ◽  
Time Lapse ◽  
Freezing Process ◽  
Distilled Water ◽  
Scientific Communities ◽  
Simple Growth

AbstractIce-spike observations in nature have sparked much interest in the scientific and non-scientific communities alike, yet most research performed thus far has been largely qualitative. We have conducted a quantitative, systematic laboratory investigation in order to assess theories explaining ice-spike growth and to determine the conditions conducive to it. We observed ice-spike growth using time-lapse digital photography, using two water types in two different containers. We observed that ice spikes occurred much more frequently in distilled water than in tap water. Digital images were analyzed to determine the growth rate of the ice spikes. Water temperature was recorded throughout the freezing process, and the cooling rate was used to estimate a bulk heat transfer coefficient. Finally, a simple model, based on mass conservation, was derived and was found to give useful predictions of ice-spike growth rate.

A New Method for Estimating Bubble Diameter At Different Gravity Levels for Nucleate Pool Boiling

2021 ◽  
Author(s):  
Sandipan Banerjee ◽  
Yongsheng Lian ◽  
Yang Liu ◽  
Mark Sussman
Keyword(s):  
Heat Transfer ◽  
Growth Rate ◽  
Vapor Bubble ◽  
Bubble Growth ◽  
Bubble Diameter ◽  
Nucleate Boiling ◽  
New Method ◽  
Space Applications ◽  
Earth Gravity ◽  
Micro Gravity

Abstract Nucleate boiling has significant applications in earth gravity( in industrial cooling applications) and micro-gravity conditions (in space exploration, specifically in making space applications more compact). However, the effect of gravity on the growth rate and bubble size is not yet well understood. We perform numerical simulations of nucleate boiling using an adaptive Moment-of-Fluid (MoF) method for a single vapor bubble (water or Perfluoro-n-hexane) in saturated liquid for different gravity levels. Results concerning the growth rate of the bubble, specifically the departure diameter and departure time have been provided. The MoF method has been first validated by comparing results with a theoretical solution of vapor bubble growth in super-heated liquid without any heat-transfer from the wall. Next, bubble growth rate, bubble shape and heat transfer results under earth gravity, reduced gravity and micro-gravity conditions are reported and they are in good agreement with experiments. Finally, a new method is proposed for estimating the bubble diameter at different gravity levels. This method is based on an analysis of empirical data at different gravity values and using power-series curve fitting to obtain a generalized bubble growth curve irrespective of the gravity value. This method is shown to provide a good estimate of the bubble diameter for a specific gravity value and time.

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