Growth and Characterization of Ti3PSe4 Single Crystals

1986 ◽  
Vol 90 ◽  
Author(s):  
N. B. Singh ◽  
R. H. Hopkins ◽  
R. Mazelsky ◽  
M. Gottlieb
Keyword(s):  
Single Crystals ◽  
Growth Parameters ◽  
Optical Transmittance ◽  
Etch Pit Density ◽  
Bridgman Technique ◽  
Absorption Bands ◽  
Cross Sectional ◽  
Etch Pit

ABSTRACTGood quality single crystals of Ti3PSe4 were grown from the melt by the Bridgman technique following improvements in the method of purifying the parent components, and optimization of growth parameters. Crack-free crystals 8 cm in length and 17 mm in diameter were produced.The quality of the crystals was evaluated by optical transmittance and metallographic techniques. In the range 0.7 to 14 μm the optical transmittance shows elimination of absorption bands exhibited in crystals grown without special purification steps. Etchpit studies showed that the crystals were free from inclusions and lamellar twins and that they show a uniform cross sectional etch pit density.

Bridgman Growth and Characterization of Bulk Single Crystals of Ga1−xInxSb for Thermophotovoltaic Applications

1997 ◽  
Vol 484 ◽  
Author(s):  
J. R. Boyer ◽  
W. T. Haines
Keyword(s):  
Growth Rate ◽  
Single Crystals ◽  
Lattice Parameter ◽  
Bridgman Technique ◽  
Low Bandgap ◽  
Bulk Single Crystals ◽  
Binary Compounds ◽  
Deposition Techniques

AbstractThermophotovoltaic generation of electricity is attracting renewed attention due to recent advances in low bandgap (0.5–0.7 eV) III-V semiconductors. The use of mixed pseudo-binary compounds allows for the tailoring of the lattice parameter and the bandgap of the material. Conventional deposition techniques (i.e., epitaxy) for producing such ternary or quaternary materials are typically slow and expensive. Production of bulk single crystals of ternary materials, for example Gal-xlnxSb, is expected to dramatically reduce such material costs. Bulk single crystals of Ga1−xInxSb have been prepared using a Bridgman technique in a two-zone furnace. These crystals are 19 mm in diameter by approximately 50 mm long and were produced using seeds of the same diameter. The effects of growth rate and starting materials on the composition and quality of these crystals will be discussed and compared with other attempts to produce single crystals of this material.

Characterization of Natural and Synthesized FeTiO3 Crystals With RBS/PIXE/XRD

1997 ◽  
Vol 07 (03n04) ◽  
pp. 265-275
Author(s):  
R. Q. Zhang ◽  
S. Yamamoto ◽  
Z. N. Dai ◽  
K. Narumi ◽  
A. Miyashita ◽  
...  
Keyword(s):  
Single Crystals ◽  
Ion Beam ◽  
Pressure Control ◽  
Floating Zone ◽  
X Ray Diffraction ◽  
X Ray ◽  
Beam Analysis ◽  
Ppm Level

Natural FeTiO 3 (illuminate) and synthesized FeTiO 3, single crystals were characterized by Rutherford backscattering spectroscopy combined with channeling technique and particle-induced x-ray emission (RBS-C and PIXE). The results obtained by the ion beam analysis were supplemented by the x-ray diffraction analysis to identify the crystallographic phase. Oriented single crystals of synthesized FeTiO 3 were grown under the pressure control of CO 2 and H 2 mixture gas using a single-crystal floating zone technique. The crystal quality of synthesized FeTiO 3 single crystals could be improved by the thermal treatment but the exact pressure control is needed to avoid the precipitation of Fe 2 O 3 even during the annealing procedure. Natural FeTiO 3 contains several kinds of impurities such as Mn , Mg , Na and Si . The synthesized samples contain Al , Si and Na which are around 100 ppm level as impurities. The PBS-C results of the natural sample imply that Mn impurities occupy the Fe sublattice in FeTiO 3 or in mixed phase between ilmenite and hematite.

scholarly journals Growth and Characterization of Epsomite Single Crystals Doped with KCl from low Temperature Aqueous Solutions

1970 ◽  
Vol 33 (1) ◽  
pp. 47-54 ◽  
Author(s):  
S Ferdous ◽  
J Podder
Keyword(s):  
Aqueous Solutions ◽  
Single Crystals ◽  
Optical Quality ◽  
Dielectric Studies ◽  
Slow Cooling ◽  
Large Size ◽  
Isothermal Evaporation ◽  
Academy Of Sciences

Highly transparent and well faceted large size epsomite single crystals have been grown in pure form and doped with KCl from aqueous solutions by slow cooling and isothermal evaporation method. The optical quality of the epsomite improves on doping by KCl. Mass growth rates were found to increase with doping of lower concentrations of KCl and then decreases with the higher concentration of KCl. KCl doped epsomite crystal reveals that structures are slightly distorted due to adsorption of Cl- ion into the crystal lattice. DC conductivity along the growth axis for all of the grown crystals increases with temperature in the range of 25 to 70ºC and also increases with the KCl concentration. Dielectric constant is found to be almost independent of frequency up to range of 106Hz. The dielectric studies show the suitability of these grown crystals for optoelectronic applications. DOI: 10.3329/jbas.v33i1.2949 Journal of Bangladesh Academy of Sciences, Vol. 33, No. 1, 47-54, 2009

Growth and Characterization of Single Crystal Epitaxial CoGa on MBE Grown III-V Semiconductors

1988 ◽  
Vol 144 ◽  
Author(s):  
K. C. Garrison ◽  
C. J. Palmstrøm ◽  
R. A. Bartynski
Keyword(s):  
Substrate Temperature ◽  
Single Crystal ◽  
Single Crystals ◽  
Structural Quality ◽  
High Quality ◽  
Auger Analysis ◽  
Post Deposition

ABSTRACTWe have demonstrated growth of high quality single crystal CoGa films on Ga1−xAlxAs. These films were fabricated in-situ by codeposition of Co and Ga on MBE grown Ga1−xAlxAs(100) surfaces. The elemental composition of the films was determined using Rutherford Backscattering (RBS) and in-situ Auger analysis. The structural quality of the films' surfaces was studied using RHEED (during deposition) and LEED (post deposition). RBS channeling was used to determine the bulk crystalline quality of these films.For ∼500 Å CoGa films grown at ∼450°C substrate temperature, channeling data showed good quality epitaxial single crystals [χmin ∼7%] with minimal dechanneling at the interface.

Reduction of Dislocations in the Bulk Growth of SiC Crystals

2006 ◽  
Vol 527-529 ◽  
pp. 3-8 ◽  
Author(s):  
Daisuke Nakamura
Keyword(s):  
Dislocation Density ◽  
Growth Process ◽  
Large Diameter ◽  
Device Performance ◽  
Etch Pit Density ◽  
Bulk Growth ◽  
Etch Pit ◽  
Low Dislocation Density ◽  
The Impact

Recent reports on the impact of elementary dislocations on device performance and reliability suggest not only micropipe defects but also dislocations should be reduced or eliminated perfectly. This paper presents bulk growth process for reduction of the dislocations, and quality of the crystals grown by the process. Etch pit density of the best crystals grown by the process was lower by three orders of magnitude than that of conventional crystals. Moreover, large diameter crystals (>2”) with low dislocation density were successfully grown by the process.

Effects of the diameter of rutile (TiO2) single crystals grown using tilting-mirror-type infrared heating image furnace on solid–liquid interface and etch pit density

2011 ◽  
Vol 317 (1) ◽  
pp. 135-138 ◽  
Author(s):  
Md. Abdur Razzaque Sarker ◽  
Satoshi Watauchi ◽  
Masanori Nagao ◽  
Takashi Watanabe ◽  
Isamu Shindo ◽  
...  
Keyword(s):  
Single Crystals ◽  
Liquid Interface ◽  
Infrared Heating ◽  
Etch Pit Density ◽  
Rutile Tio2 ◽  
Etch Pit ◽  
Solid Liquid Interface ◽  
Solid Liquid

scholarly journals Caracterización de los pacientes con labio y paladar hendido y de la atención brindada en el hospital infantil universitario de manizales (Colombia), 2010./Study of clinical and epidemiological characteristics of patients with lip and palate treated in th

2012 ◽  
Vol 12 (2) ◽  
pp. 190-198 ◽  
Author(s):  
Ingid Charry ◽  
Mónica lorena Aguirre ◽  
José jaime Castaño castrillón ◽  
Brenda juliana Gómez ◽  
Juliana Higuera ◽  
...  
Keyword(s):  
Cleft Palate ◽  
Cleft Lip ◽  
Cleft Lip And Palate ◽  
Multidisciplinary Treatment ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Calidad De Vida ◽  
Epidemiological Characteristics

Objetivo: El labio y paladar hendido es la malformación más común de cabeza y cuello en el medio colombiano, es una patología multifactorial determinada por alteraciones genéticas y ambientales. Se da en uno de cada 900 nacidos vivos afectando a varones en una mayor proporción. El objetivo del presente estudio es registrar las características sociodemográficas, clínicas y de tratamiento de 118 pacientes con labioy paladar hendido atendidos en el Hospital Infantil Universitario “Rafael Henao Toro” de la ciudad de Manizales (Colombia).Materiales y Métodos: Estudio de corte transversal en pacientes que asistieron a la clínica de labio y paladar en el mencionado hospital.Resultados: Se encontró frecuencia del sexo masculino en un 55,1%, un 51,7% procedente del área urbana y en su mayoría de los estratos III y IV, la frecuencia más alta se presentó para labio y paladar hendido grado III con 36,4%. El esquema de tratamiento más utilizado fue la palatorrafia (63,6%) y la queiloplastia (69,5%).Conclusiones: La caracterización de los pacientes con labio y Paladar Hendido indica predominio por los pacientes con diagnóstico de labio y paladar hendido Grado III, igual distribución entre géneros, procedencia urbana en los cuales el estrato IV cuenta con la mayor frecuencia. Cabe destacar la importancia de un diagnóstico oportuno además un tratamiento multidisciplinario, que cuente con apoyo personal además del quirúrgico que se verá reflejado en una buena evolución y calidad de vida de los pacientes. Background: Cleft lip and cleft palate is the most common malformation of the headand neck of our environment, is a multifactorial disease determined by genetic andenvironmental factors. It occurs in one in every 900 live births, affecting males at agreater rate, today’s advances in terms of proposed treatment from the multidisciplinaryapproach, starting with a strict evaluation by pediatric to ensure that patients are in theright conditions to initiate surgical procedures.Materials and Methods: A cross sectional study. We recorded demographic characteristics,clinical and treatment of 118 patients who attended the lip and palate clinicat Children’s Hospital University of Manizales.Results: We found more frequently in males 55.1%, 51.7% from the urban area andmost of the layers III and IV, the highest incidence is presented for cleft lip and palategrade III in 36.4% The most commonly used treatment regimen was palate surgeryand cheiloplasty.Conclusions: The characterization of patients with cleft lip and cleft palate indicatespredominance for patients with cleft lip and palate grade III, gender equality, urbanhometown strata IV which has the highest frequency. Remarkable the importance ofearly diagnosis also appropriate multidisciplinary treatment, that has support in additionto the surgical staff will be reflected in a good performance and quality of life of patients

scholarly journals Excitons in PL spectra of Cu(In, Ga)Se-=SUB=-2-=/SUB=- single crystal -=SUP=-*-=/SUP=-

2019 ◽  
Vol 61 (5) ◽  
pp. 1002
Author(s):  
E. Skidchenko ◽  
M.V. Yakushev ◽  
L. Spasevski ◽  
P.R. Edwards ◽  
M.A. Sulimov ◽  
...  
Keyword(s):  
Single Crystals ◽  
Free Exciton ◽  
Excitation Intensity ◽  
Structural Quality ◽  
Near Band Edge ◽  
Bridgman Technique ◽  
Pl Spectra ◽  
Vertical Bridgman ◽  
Ga Content

AbstractA photoluminescence (PL) study of Cu(In,Ga)Se_2 (CIGSe) single crystals, (grown by the vertical Bridgman technique) with the [Ga]/[Ga + In] ratio of 7 and 12% and the [Cu]/[In + Ga] ratio greater than unity, as measured by energy dispersive spectroscopy, is presented. Analysis of the excitation intensity and temperature dependence of the PL spectra suggested the excitonic nature of the observed near-band-edge emissions peaks. Free and bound excitons in CIGSe single crystals with both 7 and 12% Ga content are clearly observed, analyzed and identified. An activation energy of 19 meV is determined for the free exciton in the PL spectra of the sample with 12% Ga. The presence of the excitons demonstrated a high structural quality of the material.

Growth of low-etch-pit density InSb single crystals by the Czochralski method

1997 ◽  
Vol 178 (3) ◽  
pp. 422-425 ◽  
Author(s):  
J.A. Godines ◽  
R. Castillo ◽  
J. Martínez ◽  
M.E. Navarro ◽  
F. De Anda ◽  
...  
Keyword(s):  
Single Crystals ◽  
Czochralski Method ◽  
Etch Pit Density ◽  
Etch Pit
Sign in / Sign up

Export Citation Format

Share Document