Epitaxial Growth on 4H-SiC on-Axis, 0.5°, 1.25°, 2°, 4°, 8° Off-Axis Substrates – Defects Analysis and Reduction

A good selection of growth parameters (in-situ etching, C/Si ratio, growth rate) enables obtaining of ~1nm high steps of epitaxial layers, which are comparable to the size of an elementary cell (8°off-axis) and achieve the density of BPD=8•103/cm2. Due to crystallization on substrates with low misorientation (<2°off-axis) it is possible to obtain epitaxial layers substantially lacking in BPD dislocations. However, a slightly more developed surface with Ra=1-2.5nm (1.25°, 2°off-axis) characterizes these layers. By lowering the C/Si ratio, morphology of layers crystallized on substrates with low misorientation was improved. Extending growth rate improved both the crystallographic quality of the grown layers and their polytype stability. Nevertheless, growth without BPDs, also referred to as the homogeneous (4H) polytypic growth on 4H-SiC on-axis substrates, is the most efficient way of defect elimination.

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THE EFFECTS OF SEX AND AGE OF MALE AT CASTRATION ON GROWTH AND CARCASS QUALITY OF YORKSHIRE SWINE

Canadian Journal of Animal Science ◽

10.4141/cjas61-005 ◽

1961 ◽

Vol 41 (1) ◽

pp. 30-39 ◽

Cited By ~ 27

Author(s):

L. A. Charette

Keyword(s):

Growth Rate ◽

Iodine Number ◽

Feed Efficiency ◽

Carcass Characteristics ◽

Live Weight ◽

Carcass Quality ◽

Selection Of ◽

Effect On Growth

The effects of sex and age of castration of males on growth rate, feed efficiency and carcass characteristics in bacon type swine were measured using 16 pigs each as gilts, entire boars, and boars castrated at birth, 6, 12, 16, and 20 weeks of age. Castration at 20 weeks was too late since some pigs reached 200 pounds live weight before that age. Boars consumed less feed daily than barrows and gilts, were thinner in loin fat, and yielded a higher percentage of shoulder than gilts. The carcasses of boars and gilts were longer, had less fat covering over the shoulder and back, a larger area of loin, and a higher iodine number than those castrated late. Acceptability tests showed that sex or age of castration did not affect the flavour, odour, or tenderness of the meat.Purebred breeders can delay castration for better selection of boars without any serious effect on growth, physical carcass characteristics, and feed requirements. Although the market discriminates against boars, it appears questionable whether castration is necessary when boars are slaughtered at 200 pounds before they reach the age of 150 days.

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The effect of a milk diet uponPlasmodium berghei, Nuttallia (=Babesia) rodhainiandTrypanosoma bruceiinfections in mice

Parasitology ◽

10.1017/s0031182000041275 ◽

1970 ◽

Vol 61 (3) ◽

pp. 425-433 ◽

Cited By ~ 10

Author(s):

Frank Nowell

Keyword(s):

Growth Rate ◽

Normal Diet ◽

Normal Strain ◽

Fatality Rate ◽

Milk Diet ◽

Infection Pattern ◽

Selection Of

Suppression ofP. bergheiinfections but not those ofN. rodhainiorT. bruceiin mice on milk diet were noted. The suppression ofP. bergheiwas variable. This was not due to differences of the quality of the milk or to the mice eating faeces, sawdust, etc. which may be rich in PABA. The variability was at least partially due to selection of a strain of parasite probably requiring a lower level of PABA than normal. One such strain was isolated and its pattern of infection compared with the normal strain. The ‘milk diet’ strain caused a higher fatality rate in mice on milk diet but always showed a lower parasitaemia growth rate in mice on normal diet. When repassaged through mice on normal diet, the ‘milk diet’ strain did not revert immediately to the infection pattern of the normal strain.

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GaAs epitaxial layers obtained by close-spaced vapor transport in H2 + H2O and H2 + CO2 ambients: Fine control of the growth rate and its effect on the electrical properties of the layers

Canadian Journal of Physics ◽

10.1139/p94-008 ◽

1994 ◽

Vol 72 (1-2) ◽

pp. 44-50

Author(s):

D. Cossement ◽

Z. Huang ◽

G. Perron ◽

B. Jean ◽

J. P. Dodelet

Keyword(s):

Growth Rate ◽

Water Vapor ◽

Vapor Pressure ◽

Water Vapor Pressure ◽

Vapor Transport ◽

Epitaxial Layers ◽

Fine Control ◽

Experimental Values ◽

P Type

In view of developing the close-spaced vapor transport technique (CSVT) to obtain III/V homojunction solar cells, it is necessary to finely control the growth rate of GaAs epitaxial layers. This has been performed either by controlling the water vapor pressure, [Formula: see text] injected in the reactor along with H2, in H2 + H2O ambient, or by controlling the water vapor pressure generated in situ by the reaction of H2 + CO2 in the reactor. For H2 + CO2 ambient, [Formula: see text], controls [Formula: see text] according to the following reaction: [Formula: see text]. The growth rates calculated with a diffusion controlled model are in agreement with the experimental values for both ambients, including the observation of a maximum in the evolution of the growth rate with [Formula: see text], Controlling the growth rate of GaAs by changing [Formula: see text] affects the carrier density (NA–ND) of p-type layers grown from Zn-doped GaAs sources. In both ambients (NA–ND) is a function of [Formula: see text]. Such a behavior is also obtained for the calculated carrier densities. It is the result of the transport of Zn as ZnO in CSVT. In H2 + CO2 ambient, where H2O and C are generated in situ, carbon is not incorporated as a major p-type doping impurity, contrarily to expectations, n-type GaAs layers were also obtained from Te-doped GaAs sources. In that case, the measured NA–ND values are not affected by changes in [Formula: see text] because water is not involved in the transport of Te in CSVT.

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PEMILIHAN STARTER CAIR UNGGUL UNTUK FERMENTASI BIJI KAKAO

Jurnal Penelitian Pascapanen Pertanian ◽

10.21082/jpasca.v16n1.2019.19-27 ◽

2020 ◽

Vol 16 (1) ◽

pp. 19

Author(s):

NFN Misgiyarta ◽

Anas Miftah Fauzi ◽

Khaswar Syamsu ◽

S Joni Munarso

Keyword(s):

Growth Rate ◽

Reducing Sugars ◽

Cocoa Bean ◽

Microbial Count ◽

Cocoa Beans ◽

Total Acid ◽

Fermentation Temperature ◽

C 30 ◽

Selection Of

Kualitas biji kakao fermentasi rendah karena kualitas starter mikroba untuk fermentasi biji kakao rendah. Seleksi starter mikroba diperlukan untuk mendapatkan starter yang unggul. Ada dua jenis starter, yaitu starter cair dan starter kering. Starter cair banyak digunakan untuk fermentasi biji kakao. Starter yang diuji adalah starter cair, yaitu starter Inoka, starter cair BB-Pasca, dan starter yoghurt. Seleksi starter mikroba dilakukan dengan memfermentasi pulp biji kakao selama 24 jam pada berbagai suhu fermentasi (20oC, 30oC, dan 40oC). Parameter yang diamati adalah jumlah total mikroba, laju pertumbuhan mikroba starter, tingkat konsumsi gula pereduksi oleh mikroba starter, total asam yang diproduksi, tingkat penurunan pH, dan peningkatan suhu fermentasi serta korelasi antara parameter pengamatan penelitian. Starter cair unggul yang terpilih adalah starter cair Inoka. Karakteristik starter Inoka adalah memiliki tingkat laju pertumbuhan μ = 0.470, konsumsi gula pereduksi oleh mikroba starter 12%, peningkatan asam total 7%, penurunan pH 5,2, dan peningkatan suhu fermentasi 1,56oC serta korelasi antara parameter penelitian di atas 0,61. Selection of Superior Liquid Starters for Cocoa Beans FermentationThe quality of fermented cocoa beans varies because the microbial starter for fermented cocoa beans varies. The selection of starter is needed to get a superior starter. The starter tested is a liquid starter, that is the Inoka starter, the BB-Pasca liquid starter, the yoghurt. The selection of starter is done by fermenting cocoa bean pulp for 24 hours at various fermentation temperatures (20oC, 30oC and 40oC). The parameters observed were total microbial count, microbial growth rate of starter, consumption of reducing sugars by starter microbes, total acid produced, decrease of pH, and increase of fermentation temperature and the correlation between the parameters of the study. The selected superior liquid starter is the Inoka liquid starter. The characteristics of Inoka starter are to have a growth rate of μ = 0.470, consumption of reducing sugars by starter microbes 12%, total acid increase of 7%, decrease in pH 5.2, and increase in fermentation temperature of 1.56oC and correlation between research parameters above 0.61.

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Investigation of MOCVD growth parameters on the quality of GaN epitaxial layers

Journal of Crystal Growth ◽

10.1016/j.jcrysgro.2010.10.047 ◽

2011 ◽

Vol 318 (1) ◽

pp. 436-440 ◽

Cited By ~ 4

Author(s):

X.G. Zhang ◽

B. Soderman ◽

E. Armour ◽

A. Paranjpe

Keyword(s):

Growth Parameters ◽

Epitaxial Layers ◽

Mocvd Growth

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Reduction of the Surface Density of Single Shockley Faults by TCS Growth Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.679-680.67 ◽

2011 ◽

Vol 679-680 ◽

pp. 67-70 ◽

Cited By ~ 9

Author(s):

Andrea Canino ◽

Massimo Camarda ◽

Francesco La Via

Keyword(s):

Growth Rate ◽

Vapor Deposition ◽

Surface Density ◽

Growth Process ◽

Chemical Vapor ◽

Deposition Process ◽

Epitaxial Layers ◽

Spatially Resolved ◽

Basal Plane Dislocation

Spatially resolved micro-photoluminescence has been used to study the Single Shockley faults surface density and properties on 4H-SiC epitaxial layers. The improvement of quality of epitaxial layers due to the chemical vapor deposition process has been studied by measuring the reduction of mean density of Single Shockley faults. The change of faults density has been correlated to the different precursor gas used for the growth. In fact trichlorosilane has been used instead of silane. The change of precursor led to two different advantages: the reduction of basal plane dislocation surface density and the capability to increase the growth rate of the process. Both these features allow reducing the density of Single Shockley faults.

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Growth Conditions of Erbium-Oxygen-Doped Silicon Grown by MBE

MRS Proceedings ◽

10.1557/proc-422-15 ◽

1996 ◽

Vol 422 ◽

Cited By ~ 6

Author(s):

J. Stimmer ◽

A. Reittinger ◽

G. Abstreiter ◽

H. Holzbrecher ◽

Ch. Buchal

Keyword(s):

Molecular Beam Epitaxy ◽

Systematic Study ◽

Molecular Beam ◽

Growth Parameters ◽

Light Emitting Diode ◽

Growth Conditions ◽

Light Emitting ◽

Doped Silicon

AbstractWe report on a systematic study of the growth parameters of erbium-oxygen-doped silicon grown by molecular beam epitaxy. The surface quality of the grown layers was measured in situ by RHEED. The samples were characterized by photoluminescence measurements and SIMS. An Er-O-doped Si light emitting diode grown with the optimized parameters is presented.

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Selective Area Heteroepitaxy of Nano-AlGaN UV Excitation Sources for Biofluorescence Application

MRS Proceedings ◽

10.1557/proc-0916-dd05-03 ◽

2006 ◽

Vol 916 ◽

Cited By ~ 3

Author(s):

Vibhu Jindal ◽

James Grandusky ◽

Fatemeh Shahedipour-Sandvik ◽

Steven LeBoeuf ◽

Joleyn Balch ◽

...

Keyword(s):

Growth Rate ◽

Growth Parameters ◽

Growth Conditions ◽

X Ray Diffraction ◽

High Quality ◽

X Ray ◽

Selective Area ◽

Mask Material ◽

Uv Excitation ◽

Selection Of

AbstractWe report on the selective area heteroepitaxy and facet evolution of AlGaN nanostructures on GaN/sapphire substrate using various mask materials. We also report on the challenges associated with selection of an appropriate mask material for selective area heteroepitaxy of AlGaN with varying Al composition. The shape and the growth rate of the nanostructures are observed to be greatly affected by the mask material. The evolution of the AlGaN nanostructures and Al incorporation were studied exhaustively as a function of growth parameters; including temperature, pressure, NH3 flow, total alkyl flow and TMAl/(TMAl+TMGa) ratio. The growth rate of nanostructures was reduced drastically when higher Al percentage AlGaN nanostructures were grown. The growth rates were increased for higher Al percentage AlGaN using a surfactant which resulted in a high quality pyramidal structure. As indicated by high resolution x-ray diffraction (XRD) and cathodoluminescence (CL) spectroscopy, composition of Al in the AlGaN nanostructure is significantly different from that of a thin film grown under the same growth conditions.

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Selective area heteroepitaxy of nano-AlGaN ultraviolet excitation sources for biofluorescence application

Journal of Materials Research ◽

10.1557/jmr.2007.0141 ◽

2007 ◽

Vol 22 (4) ◽

pp. 838-844 ◽

Cited By ~ 4

Author(s):

Vibhu Jindal ◽

James R. Grandusky ◽

Neeraj Tripathi ◽

Fatemeh Shahedipour-Sandvik ◽

Steven LeBoeuf ◽

...

Keyword(s):

Growth Rate ◽

Growth Parameters ◽

Growth Conditions ◽

X Ray Diffraction ◽

X Ray ◽

Ultraviolet Excitation ◽

Selective Area ◽

Cathodoluminescence Spectroscopy ◽

Mask Material ◽

Selection Of

We report on the selective area heteroepitaxy and facet evolution of AlGaN nanostructures on GaN/sapphire substrate using various mask materials. We also report on the challenges associated with selection of an appropriate mask material for selective area heteroepitaxy of AlGaN with varying Al composition. The shape and the growth rate of the nanostructures are observed to be greatly affected by the mask material. The evolution of the AlGaN nanostructures and Al incorporation were studied exhaustively as a function of growth parameters including temperature, pressure, NH3 flow, total alkyl flow, and TMAl/(TMAl+TMGa) ratio. The growth rate of nanostructures was reduced drastically when higher Al percentage AlGaN nanostructures were grown. The growth rates were increased for higher Al percentage AlGaN using a surfactant, which resulted in a high-quality pyramidal structure. As indicated by high-resolution x-ray diffraction and cathodoluminescence spectroscopy, the composition of Al in the AlGaN nanostructure is significantly different from that of a thin film grown under the same growth conditions.

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In-Situ Spectroscopic Ellipsometry for the Control of Si based Thin Multi-Layers Grown by UHV-CVD

MRS Proceedings ◽

10.1557/proc-342-69 ◽

1994 ◽

Vol 342 ◽

Cited By ~ 1

Author(s):

F. Glowacki ◽

A. Larre ◽

F. Ferrieu ◽

Y. Campidelli ◽

D. Bensahel

Keyword(s):

Growth Rate ◽

Quantum Well ◽

Spectroscopic Ellipsometry ◽

Growth Parameters ◽

Optical Data ◽

Surface Control ◽

Different Temperatures ◽

Multi Quantum Well

ABSTRACTIn-situ Spectroscopic Ellipsometry as a function of time is used to follow the growth of Si/SiGe Multi Quantum Well (MQW) structures. It provides both the starting surface control and the growth parameters understanding (thickness, growth rate, Ge content). Si and SiGe optical data were recorded at different temperatures on individual Si and SiGe layers. Using the measured indices and the known thicknesses of the layers, the experimental MQW data are fitted without adjustable parameters.

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