scholarly journals Влияние режима получения образцов и термообработки на локальную структуру халькогенидного полупроводника Ge-=SUB=-2-=/SUB=-Sb-=SUB=-2-=/SUB=-Te-=SUB=-5-=/SUB=-

2022 ◽  
Vol 56 (3) ◽  
pp. 291
Author(s):  
С.Н. Гарибова ◽  
А.И. Исаев ◽  
С.И. Мехтиева ◽  
С.У. Атаева ◽  
Р.И. Алекперов
Keyword(s):  
Heat Treatment ◽  
Thermal Processing ◽  
Thermal Evaporation ◽  
Amorphous State ◽  
Hexagonal Structure ◽  
Structural Elements ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Matrix ◽  
Close Range

Specifics of "amorphous state - crystal" phase transitions in dependence on the samples obtaining method and thermal processing, as well as changes in the structure and close range order in the arrangement of the atoms of Ge20Sb20.5Te51 chalcogenide semiconductors have been studied by the x-ray diffraction and Raman spectroscopy. It has been shown that Ge20Sb20.5Te51 films obtained by thermal evaporation on an unheated substrate are amorphous; after heat treatment at 220 and 400 °C, transform into a crystalline phase with a cubic and hexagonal structure. The chemical bonds and the main structural elements that form the matrix of the investigated objects, as well as the changes that occur in them during heat treatment, have been determined.

Detection Confirmation and Determination of Trace Amounts of Selenium by X-Ray Methods

1963 ◽  
Vol 7 ◽  
pp. 542-554
Author(s):  
Frank L. Chan
Keyword(s):  
Matrix Effects ◽  
Hexagonal Structure ◽  
Elemental Selenium ◽  
X Ray Diffraction ◽  
X Ray ◽  
Yellow Color ◽  
The Matrix ◽  
Ray Methods ◽  
Tetravalent State

AbstractRecently, interest in the determination of selenium in trace amounts has been greatly intensified because of the nutritional aspects of this element. It has been reported that selenium in the amount of 13 μg in the form of sodium selenite in 100 g of feed has an effect similar to that of vitamin E. In the field of semiconductors, the detection and determination of trace amounts of selenium in arsenic, antimony, and small single crystals of solid solution of cadmium selenide and sulfide are of considerable importance in semiconductor performance.In the Aerospace Research Laboratories, 4,5 diamino-6-tbiopyi-imidine has been successfully adopted as a reagent for the spectrophotometric determination of selenium. The reaction of 4,5 diamino-6-thiopyrimidine and tetxavalent selenium produces a yellow color with the formation of elemental selenium. It is possible to determine elemental selenium by collecting it in a thin layer. The selenium deposited in this layer may then be determined by an X-ray fluorescence method. A procedure of this nature has the advantage of eliminating the matrix effects commonly encountered in X-ray fluorescence. Furthermore, the slow generation of selenium affords a convenient means of detection and confirmation of this element by the use of X-ray diffraction procedures. By this technique selenium is first converted to its tetravalent state and is then reacted with 4,5 diamino-6-thiopyrimidine. On standing, the selenium is reduced to a red precipitate of elemental selenium which can be dissolved in carbon disulfide. Finally, the selenium can be converted into its hexagonal structure by annealing at 205-207°C.

Effect of Annealing Treatment on Structure and Electrochemical Properties of LaNi4.5Co0.25Al0.25 Alloy with Low Co Content

2013 ◽  
Vol 788 ◽  
pp. 141-146
Author(s):  
Feng Wang ◽  
Huai Ying Zhou ◽  
Jiang Wang ◽  
Zhong Min Wang ◽  
Huai Gang Zhang ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Electrochemical Properties ◽  
Discharge Capacity ◽  
Annealing Treatment ◽  
Electrochemical Measurement ◽  
X Ray Diffraction ◽  
Capacity Retention ◽  
X Ray ◽  
The Matrix ◽  
Suitable Treatment

The effect of annealing treatment on the structure and electrochemical properties of LaNi4.5Co0.25Al0.25 alloy was studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical measurement. XRD results show that the matrix phases are still LaNi5 (hexagonal CaCu5 type structure) but the intensity peaks become sharper after heat treatment. Electrochemical experiments at 301 K indicate that annealing treatment can significantly improve the discharge capacity and cyclic stability of LaNi4.5Co0.25Al0.25 alloy at suitable treatment condition. The alloy has the best discharge capacity (324.4 mAg-1) due to its composition homogenization after heat treatment at 1373 K/8 h, while the best capacity retention is about 80.12 % because of lower expansion rate and better anti-pulverization ability after heat treatment at 1273 K/8 h.

scholarly journals Effect of Ag in CdSe thin films prepared using thermal evaporation

2017 ◽  
Vol 51 (12) ◽  
pp. 1656
Author(s):  
T.C.M. Santhosh ◽  
Kasturi V. Bangera ◽  
G.K. Shivakumar
Keyword(s):  
Thin Films ◽  
Band Gap ◽  
Thermal Evaporation ◽  
Hexagonal Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Glass Substrates ◽  
Potential Applications ◽  
Evaporation Technique ◽  
Transmission Measurements

It has been a general practice to dope thin films with suitable dopants to modify the properties of the films to make them more suitable for potential applications. When the dopant concentrations are low, they do not normally affect the structure and morphology of the films. However, it may lead to drastic changes in electronic properties of the films. This might result from the dopant getting incorporated into the lattice of the material of the films. Cadmium selenide is an important compound semiconductor material with an attractive energy band gap. The present work relates to an attempt made to dope CdSe thin films with silver. CdSe : Ag (1 to 5%) thin films were deposited on glass substrates at an optimized substrate temperature of 453 K using thermal evaporation technique. The grown films were analyzed using X-ray diffraction, scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDX) techniques. It is observed that undoped CdSe thin films and CdSe : Ag films have hexagonal structure. The grain size was found to increase marginally with an increase in the Ag concentration. The optical band gap of the films determined by optical transmission measurements agree with that of CdSe. Electrical conductivity is observed to increase from 10-4 to 3.66 (Omega ·cm)-1 on addition of silver. The variation of resistance with temperature indicates that the prepared films consist of CdSe and Ag existing as two separate phases coexisting and contributing individually to the resistivity of the films. DOI: 10.21883/FTP.2017.12.45181.8430

Effects of Heat Treatment on Microstructure of Sputter Deposited TiNiPd Film on Si Wafer

2005 ◽  
Vol 475-479 ◽  
pp. 3819-3822 ◽  
Author(s):  
Shi Qiang Qian ◽  
Jian Sheng Wu
Keyword(s):  
Thin Film ◽  
Heat Treatment ◽  
Amorphous State ◽  
Diffraction Experiment ◽  
X Ray Diffraction ◽  
Free Standing ◽  
X Ray ◽  
Amorphous Thin Films ◽  
Sputter Deposited ◽  
Si Wafer

Amorphous thin Films of Ti51.78 Ni22.24Pd25.98 alloys were deposited onto 2 inch diameter n-type (100)Si wafer by r.f. magnetron sputtering. The crystallization temperature from an amorphous state to crystallization of free-standing thin film was found to be 553.1oC, but that of non-free-standing thin film on Si wafer was found to be higher from X-ray diffraction experiment. The film heated 1 h at 550 oC was partly crystallized but at 650 oC was almost whole crystallized. The film heated 1 h at 750 oC quite crystallized and some precipitation appear. Heated 50 h at 450 oC before crystallization the films would be accelerate B19' but restrain B19 formation in succeeding heat-treatment.

Effect of Ultrasonication on Synthesis of Forsterite Ceramics

2012 ◽  
Vol 576 ◽  
pp. 252-255 ◽  
Author(s):  
K.Y. Sara Lee ◽  
K.M. Christopher Chin ◽  
Ramesh Singh ◽  
C.Y. Tan ◽  
M.A. Hassan ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Crystallite Size ◽  
Ball Milling ◽  
Magnesium Oxide ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
The Matrix ◽  
Processing Steps

The current study is to examine the effect of ultrasonication on the synthesis of forsterite (Mg2SiO4) powder. Ultrasonication and ball milling were performed using talc and magnesium oxide as starting precursors, followed by heat treatment to obtain forsterite. The X-ray diffraction results of the powders heat treated at 1200°C showed that the 2 hours ultrasonication followed by 3 hours ball milling was beneficial in retaining the forsterite phase in the matrix. The results were similar to ball milling for 10 hours prior to heat treatment. The derived powders also exhibited very fine crystallite size in the range of 28 to 35 nm thus indicating the viability of using ultrasonication as part of the processing steps in the synthesizing of forsterite ceramics.

Effect of Heat Treatment on Hardness Behavior of AZ91 and AZ91 Reinforced Carbon Nanotube

2015 ◽  
Vol 815 ◽  
pp. 79-83
Author(s):  
Nur Hidayah Ahmad Zaidi ◽  
Shamsul Baharin Jamaludin ◽  
Khairel Rafezi Ahmad ◽  
Norzilah Abdul Halif ◽  
Sinar Arzuria Adnan
Keyword(s):  
Heat Treatment ◽  
Carbon Nanotube ◽  
Mechanical Alloying ◽  
Diffraction Pattern ◽  
Rockwell Hardness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hardness Tester ◽  
Β Phase ◽  
The Matrix

In the present work the effect of heat treatment on the hardness behavior of AZ91 and AZ91 reinforced carbon nanotube were investigated under FESEM, Xrd and Rockwell hardness tester. Cnt was embedded homogenously into the matrix due to successfully mechanical alloying using planetary milling. Kinetic precipitation of β-phase (Mg17Al12) also reveal in the X-ray diffraction pattern. Meanwhile, the artificial aged nanocomposite found decreased in hardness, compare to monolithic has higher value form early aged until 36 hours aging.

New Structure of CTAB Templated Silica Films as revealed by GISAXS coupled to HRTEM

2000 ◽  
Vol 628 ◽  
Author(s):  
Sophie Besson ◽  
Catherine Jacquiod ◽  
Thierry Gacoin ◽  
André Naudon ◽  
Christian Ricolleau ◽  
...  
Keyword(s):  
Cetyltrimethylammonium Bromide ◽  
Grazing Incidence ◽  
Hexagonal Structure ◽  
X Ray Diffraction ◽  
Electronic Microscopy ◽  
Silica Films ◽  
X Ray ◽  
X Ray Scattering ◽  
Hexagonal Arrangement ◽  
Spherical Micelles

ABSTRACTA microstructural study on surfactant templated silica films is performed by coupling traditional X-Ray Diffraction (XRD) and Transmission Electronic Microscopy (TEM) to Grazing Incidence Small Angle X-Ray Scattering (GISAXS). By this method it is shown that spin-coating of silicate solutions with cationic surfactant cetyltrimethylammonium bromide (CTAB) as a templating agent provides 3D hexagonal structure (space group P63/mmc) that is no longer compatible with the often described hexagonal arrangement of tubular micelles but rather with an hexagonal arrangement of spherical micelles. The extent of the hexagonal ordering and the texture can be optimized in films by varying the composition of the solution.

Structural and optical properties of Tin Oxide and Indium doped SnO2 thin films deposited by thermal evaporation technique

2016 ◽  
Vol 12 (3) ◽  
pp. 4394-4399
Author(s):  
Sura Ali Noaman ◽  
Rashid Owaid Kadhim ◽  
Saleem Azara Hussain
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Tin Oxide ◽  
Thermal Evaporation ◽  
Pure Sno2 ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
X Ray ◽  
Evaporation Technique ◽  
Sno2 Thin Films

Tin Oxide and Indium doped Tin Oxide (SnO2:In) thin films were deposited on glass and Silicon  substrates  by  thermal evaporation technique.  X-ray diffraction pattern of  pure SnO2 and SnO2:In thin films annealed at 650oC and the results showed  that the structure have tetragonal phase with preferred orientation in (110) plane. AFM studies showed an inhibition of grain growth with increase in indium concentration. SEM studies of pure  SnO2 and  Indium doped tin oxide (SnO2:In) ) thin films showed that the films with regular distribution of particles and they have spherical shape.  Optical properties such as  Transmission , optical band-gap have been measured and calculated.

X- ray diffraction and dielectric properties of PbSe thin films

2019 ◽  
Vol 15 (34) ◽  
pp. 1-14
Author(s):  
Bushra A. Hasan
Keyword(s):  
Thin Films ◽  
Thermal Activation ◽  
Thermal Evaporation ◽  
Thermal Activation Energy ◽  
Dielectric Constants ◽  
Conductivity Measurements ◽  
X Ray Diffraction ◽  
Thermal Evaporation Method ◽  
X Ray ◽  
Glass Substrates

Lead selenide PbSe thin films of different thicknesses (300, 500, and 700 nm) were deposited under vacuum using thermal evaporation method on glass substrates. X-ray diffraction measurements showed that increasing of thickness lead to well crystallize the prepared samples, such that the crystallite size increases while the dislocation density decreases with thickness increasing. A.C conductivity, dielectric constants, and loss tangent are studied as function to thickness, frequency (10kHz-10MHz) and temperatures (293K-493K). The conductivity measurements confirm confirmed that hopping is the mechanism responsible for the conduction process. Increasing of thickness decreases the thermal activation energy estimated from Arhinus equation is found to decrease with thickness increasing. The increase of thickness lead to reduce the polarizability α while the increasing of temperature lead to increase α.

scholarly journals X-ray Determination of Compressive Residual Stresses in Spring Steel Generated by High-Speed Water Quenching

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1154
Author(s):  
Diego E. Lozano ◽  
George E. Totten ◽  
Yaneth Bedolla-Gil ◽  
Martha Guerrero-Mata ◽  
Marcel Carpio ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Residual Stresses ◽  
High Speed ◽  
Spring Steel ◽  
X Ray Diffraction ◽  
Laboratory Equipment ◽  
X Ray ◽  
Water Chamber ◽  
Hardened Case ◽  
Compressive Residual Stresses

Automotive components manufacturers use the 5160 steel in leaf and coil springs. The industrial heat treatment process consists in austenitizing followed by the oil quenching and tempering process. Typically, compressive residual stresses are induced by shot peening on the surface of automotive springs to bestow compressive residual stresses that improve the fatigue resistance and increase the service life of the parts after heat treatment. In this work, a high-speed quenching was used to achieve compressive residual stresses on the surface of AISI/SAE 5160 steel samples by producing high thermal gradients and interrupting the cooling in order to generate a case-core microstructure. A special laboratory equipment was designed and built, which uses water as the quenching media in a high-speed water chamber. The severity of the cooling was characterized with embedded thermocouples to obtain the cooling curves at different depths from the surface. Samples were cooled for various times to produce different hardened case depths. The microstructure of specimens was observed with a scanning electron microscope (SEM). X-ray diffraction (XRD) was used to estimate the magnitude of residual stresses on the surface of the specimens. Compressive residual stresses at the surface and sub-surface of about −700 MPa were obtained.

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