Use of chlorinated carbon and silicon precursors for epitaxial growth of 4H-SiC at very high growth rates

2009 ◽  
Vol 3 (5) ◽  
pp. 157-159 ◽  
Author(s):  
Siva Kotamraju ◽  
Bharat Krishnan ◽  
Yaroslav Koshka
2008 ◽  
Vol 600-603 ◽  
pp. 115-118 ◽  
Author(s):  
Henrik Pedersen ◽  
Stefano Leone ◽  
Anne Henry ◽  
Franziska Christine Beyer ◽  
Vanya Darakchieva ◽  
...  

The chlorinated precursor methyltrichlorosilane (MTS), CH3SiCl3, has been used to grow epitaxial layers of 4H-SiC in a hot wall CVD reactor, with growth rates as high as 170 µm/h at 1600°C. Since MTS contains both silicon and carbon, with the C/Si ratio 1, MTS was used both as single precursor and mixed with silane or ethylene to study the effect of the C/Si and Cl/Si ratios on growth rate and doping of the epitaxial layers. When using only MTS as precursor, the growth rate showed a linear dependence on the MTS molar fraction in the reactor up to about 100 µm/h. The growth rate dropped for C/Si < 1 but was constant for C/Si > 1. Further, the growth rate decreased with lower Cl/Si ratio.


2016 ◽  
Vol 48 (4) ◽  
pp. 305-310 ◽  
Author(s):  
Yngvar GAUSLAA ◽  
Md Azharul ALAM ◽  
Knut Asbjørn SOLHAUG

AbstractIn order to improve growth chamber protocols for lichens, we tested the effect of 1) wet filter paper versus self-drained nets as a substratum for lichens, and 2) gradual versus abrupt transitions between dark and light periods. For Lobaria pulmonaria (L.) Hoffm. cultivated on nets, RGR increased by 60% compared to those on wet papers, whereas abrupt on/off transitions between day/night gave as high growth rates as gradual transitions mimicking sunrise/sunset. Because thalli on nets had less surface water than those on papers, the higher RGR on nets likely resulted from less suprasaturation depression of photosynthesis. By supporting very high growth and eliminating any visible damage, the revised growth chamber protocols facilitate new functional lichen studies.


2007 ◽  
Vol 556-557 ◽  
pp. 157-160 ◽  
Author(s):  
Francesco La Via ◽  
Stefano Leone ◽  
Marco Mauceri ◽  
Giuseppe Pistone ◽  
Giuseppe Condorelli ◽  
...  

The growth rate of 4H-SiC epi layers has been increased by a factor 19 (up to 112 μm/h) with respect to the standard process with the introduction of HCl in the deposition chamber. The epitaxial layers grown with the addition of HCl have been characterized by electrical, optical and structural characterization methods. An optimized process without the addition of HCl is reported for comparison. The Schottky diodes, manufactured on the epitaxial layer grown with the addition of HCl at 1600 °C, have electrical characteristics comparable with the standard epitaxial process with the advantage of an epitaxial growth rate three times higher.


1997 ◽  
Vol 467 ◽  
Author(s):  
M. Heintze

ABSTRACTThe interest in plasma deposition using very high frequency (VHF) excitation arose after the preparation of a-Si:H at high growth rates was demonstrated. Subsequently the improved process flexibility and the control of material properties offered by the variation of the plasma excitation frequency was recognized. The preparation of amorphous and microcrystalline thin films in a VHF-plasma is described. The increased growth rates have been attributed to an enhancement of film precursor formation at VHF, to the decreased sheath thickness as well as to an enhancement of the surface reactivity by positive ions. Plasma diagnostic investigations show that the parameters mainly affected by the excitation frequency are the ion flux to the electrodes as well as the sheaths potentials and widths, rather than the plasma density.


2002 ◽  
Vol 753 ◽  
Author(s):  
H. Bei ◽  
E. P. George ◽  
G. M. Pharr

ABSTRACTDirectional solidification of Cr-Cr3Si eutectic alloys has been carried out using a high temperature optical floating zone furnace. Uniform and well-aligned lamellar structures were obtained over a fairly wide range of intermediate growth rates but not at very low or very high growth rates where degenerate and cellular structures, respectively, were obtained. The lamellar spacing was found to increase with decreasing solidification rate, in agreement with the Jackson-Hunt theory. In addition, for a fixed growth rate, the lamellar spacing was found to increase with increasing rotation rate. Lamellar structures could also be produced at off-eutectic compositions, but only for a limited range of growth conditions. The Cr-rich lamellae are effective in stopping indention cracks nucleated in the brittle Cr3Si phase.


2014 ◽  
Vol 778-780 ◽  
pp. 117-120 ◽  
Author(s):  
Hiroaki Fujibayashi ◽  
Masahiko Ito ◽  
Hideki Ito ◽  
Isaho Kamata ◽  
Masami Naitou ◽  
...  

A single wafer type 150 mm vertical 4H-SiC epitaxial reactor with high-speed wafer rotation was developed. The rotation of the wafer at high speed significantly enhances the growth rate, and high growth rates of 40–50 μm/h are possible on 4°off-cut 4H-SiC substrates. In addition, a low defect density and smooth surface without macro step bunching can be achieved. Excellent uniformity of thickness and doping concentration was obtained for a 150 mm wafer at a high growth rate of 50 μm/h.


2001 ◽  
Vol 89 (4) ◽  
pp. 2404-2413 ◽  
Author(s):  
W. M. M. Kessels ◽  
R. J. Severens ◽  
A. H. M. Smets ◽  
B. A. Korevaar ◽  
G. J. Adriaenssens ◽  
...  

2011 ◽  
Vol 44 (23) ◽  
pp. 232003 ◽  
Author(s):  
R J Mendelsberg ◽  
S H N Lim ◽  
Y K Zhu ◽  
J Wallig ◽  
D J Milliron ◽  
...  

2012 ◽  
Vol 717-720 ◽  
pp. 113-116 ◽  
Author(s):  
Stefano Leone ◽  
Henrik Pedersen ◽  
Franziska Christine Beyer ◽  
Sven Andersson ◽  
Olof Kordina ◽  
...  

A review of recently achieved results with the chloride-based CVD on 8° and 4° off axis and nominally on-axis 4H-SiC wafers is done to clarify the epitaxial growth mechanisms on different off-angle substrates. The process conditions selected for each off-axis angle become even more difficult when running at growth rates of 100 µm/h or more. A fine-tuning of process parameters mainly temperature, C/Si ratio and in situ surface preparation is necessary for each off-angle. Some trends related to the surface properties and the effective C/Si ratio existing on the surface prior to and during the epitaxial growth can be observed.


Author(s):  
Saule Zhangirovna Asylbekova ◽  
Kuanysh Baibulatovich Isbekov ◽  
Vladimir Nickolaevich Krainyuk

Pike-perch is an invader for the water basins of Central Kazakhstan. These species have stable self-reproductive populations in the regional waters. Back calculation method was used to investigate pike-perch growth rates in reservoirs of K. Satpayev’s channel. For comparison, the data from the other water bodies (Vyacheslavsky and Sherubay-Nurinsky water reservoirs) were used, as well as literature data. Pike-perch species from the investigated waters don’t show high growth rates. The populations from the reservoirs of K. Satpayev’s channel have quite similar growth rates with populations from the Amur river, from a number of reservoirs in the Volga river basin and from the reservoir in Spain. Sexual differences in growth have not been observed. Evaluating possible influence of various abiotic and biotic factors on the growth rate of pike-perch in the reservoirs of K. Satpayev’s channel was carried out. It has been stated that the availability of trophic resources cannot play a key role in growth dynamics because of their high abundance. Morphology of water bodies also does not play a role, as well as chromaticity, turbidity and other optical water indicators. It can be supposed that the main factor influencing growth of pike perch is the habitat’s temperature. This factor hardly ever approaches optimal values for the species in reservoirs of K. Satpaev’s channel. The possible influence of fishing selectivity on pike-perch growth rates was also evaluated. Currently, there has been imposed a moratorium on pike-perch catch. However, pike-perch is found in by-catches and in catches of amateur fishermen. It should be said that such seizures have an insignificant role in the dynamics of growth rates.


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