Improvement of Crystallization Rate in Post-Annealed Ge2Sb2Te5 Films

2010 ◽  
Vol 459 ◽  
pp. 23-26
Author(s):  
Kenta Kawarai ◽  
Tamihiro Gotoh
Keyword(s):  
Structural Change ◽  
Thermal Annealing ◽  
Crystallization Temperature ◽  
Crystallization Rate ◽  
Optical Transmittance ◽  
X Ray Diffraction ◽  
X Ray ◽  
Crystallization Behaviors ◽  
Diffraction Patterns ◽  
Crystalline Peak

Crystallization behaviors of dc sputtered Ge2Sb2Te5 films were studied by X-ray diffraction and transient optical transmittance. Crystalline peak at 29.0° in diffraction patterns appeared after thermal annealing at 180 and 210 °C. Crystallization rate increased after thermal annealing below crystallization temperature. These observations indicate that heat-induced structural change enhances crystallization rate of Ge2Sb2Te5films.

scholarly journals Structural transitions in Pb(In1∕2Nb1∕2)O3 under pressure

2015 ◽  
Vol 05 (04) ◽  
pp. 1550033 ◽  
Author(s):  
Muhtar Ahart ◽  
Maddury Somayazulu ◽  
Seiji Kojima ◽  
Naohiko Yasuda ◽  
Sergey Prosandeev ◽  
...  
Keyword(s):  
Structural Change ◽  
Ground State ◽  
First Principles ◽  
Room Temperature ◽  
First Principles Calculations ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns ◽  
Pressure Evolution ◽  
Linear Compressibility

Room-temperature Raman scattering and x-ray diffraction measurements together with first-principles calculations were employed to investigate the behavior of disordered Pb(In[Formula: see text]Nb[Formula: see text]O3 (PIN) under pressure up to 50[Formula: see text]GPa. Raman spectra show broad bands but a peak near the 380[Formula: see text]cm[Formula: see text] increases its intensity with pressure. The linewidth of the band at 550[Formula: see text]cm[Formula: see text] also increases with pressure, while two of the Raman peaks merge above 6[Formula: see text]GPa. Above 16[Formula: see text]GPa, we observe additional splitting of the band at 50[Formula: see text]cm[Formula: see text]. The pressure evolution of the diffraction patterns for PIN shows obvious Bragg peaks splitting above 16[Formula: see text]GPa; consistent with a symmetry lowering transition. The transition at 0.5[Formula: see text]GPa is identified as a pseudo-cubic to orthorhombic (Pbam) structural change whereas the transition at 16[Formula: see text]GPa is isostructure and associated with changes in linear compressibility and octahedral titling, and the transition at 30[Formula: see text]GPa is associated to an orthorhombic to monoclinic change. First-principles calculations indicate that the Pbam structure is ground state with antiferrodisdortion consistent with experiment.

Effect of thermal annealing in a-InxGa1–xN films prepared by reactive RF-sputtering

2014 ◽  
Vol 92 (7/8) ◽  
pp. 943-946 ◽  
Author(s):  
Toshimasa Suzuki ◽  
Ruichi Katayama ◽  
Shun Hibino ◽  
Yoshinori Kato ◽  
Fumitaka Ohashi ◽  
...  
Keyword(s):  
Thermal Annealing ◽  
Room Temperature ◽  
Rf Sputtering ◽  
Large Change ◽  
Dark Conductivity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Radio Frequency Sputtering ◽  
Diffraction Patterns ◽  
Composition Ratios

We deposited amorphous indium gallium nitride (a-InxGa1–xN) films at room temperature by reactive radio frequency sputtering with GaN and InN targets and investigated the change of their properties from thermal annealing at annealing temperatures, Ta, below 200 °C. A large change in the indium and nitrogen composition ratios was not observed by thermal annealing at a Ta below 200 °C. In the X-ray diffraction patterns of the films annealed at a Ta below 200 °C, no perceivable peaks assigned to crystalline InxGa1–xN were found. The photoconductivty, σp, increased with an increase in Ta. On the other hand, the increase of the dark conductivity, σd, was very small with an increase in Ta below 200 °C. As a result, the photosensitivity, σp/σd, increased from 252 to 2500 by thermal annealing at a Ta of 200 °C.

The Fabrication of Fe-Doped TiCoSb Thin Films by Magnetron Sputtering and Rapid Thermal Annealing

2013 ◽  
Vol 341-342 ◽  
pp. 129-133
Author(s):  
Juan Qin ◽  
Niu Yi Sun ◽  
Guo Hua Wang ◽  
Min Zhang ◽  
Wei Min Shi ◽  
...  
Keyword(s):  
Thin Films ◽  
Magnetron Sputtering ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Seebeck Coefficient ◽  
Diffraction Patterns ◽  
P Type ◽  
Narrow Band Gap Semiconductors

TiCoSb-based half-Heusler compounds, which are narrow band gap semiconductors with a high Seebeck coefficient, have been intensively studied in bulk form but rarely in thin films. In this article TiFexCo1-xSb (x=0, 0.17) thin films were synthesized on n-type single crystal Si (100) and MgO (100) substrates by DC magnetron sputtering followed by rapid thermal annealing. The X-ray diffraction patterns show that Fe doping does not affect the crystallization temperature of TiCoSb phase, but seem to induce the formation of binary phases like TiSb. Hall measurements reveal that the undoped TiCoSb thin films are n-type semiconducting, while TiFe0.2Co0.8Sb turns to p-type with half-order higher carrier concentration of 1.5×1021cm-3. The vibrating sample magnetometer spectrum indicate that the TiCoSb thin film is non-magnetic and TiFexCo1-xSb (x=0.17) is weak magnetic.

Untersuchungen zum Kristallisationsprozeß in Selenpreßkörpern

1972 ◽  
Vol 27 (7) ◽  
pp. 1124-1126
Author(s):  
J Kispéter ◽  
L Gombay ◽  
J Lang
Keyword(s):  
Particle Size ◽  
Spectral Dependence ◽  
Crystallization Rate ◽  
Trap Depth ◽  
X Ray Diffraction ◽  
Thermally Stimulated Current ◽  
X Ray ◽  
Diffraction Patterns

Abstract The crystallization of compressed selenium was investigated by measurements of the spectral dependence of the photocurrent and of the thermally stimulated current (TSC). A comparison of these results with X-ray diffraction patterns indicates that the maxima of the photocurrent and trap depth calculated from TSC measurements depend on changes in crystallization rate and in-crease in particle size

scholarly journals The Effect of Annealing Ambience on the Material and Photodetector Characteristics of Sputtered ZnGa2O4 Films

Nanomaterials ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2316
Author(s):  
Anoop Kumar Singh ◽  
Shiau-Yuan Huang ◽  
Po-Wei Chen ◽  
Jung-Lung Chiang ◽  
Dong-Sing Wuu
Keyword(s):  
Thermal Annealing ◽  
Crystalline Structure ◽  
Visible Region ◽  
X Ray Diffraction ◽  
Substantial Impact ◽  
Single Crystalline ◽  
X Ray ◽  
Transmission Electron ◽  
Diffraction Patterns ◽  
Crystallographic Planes

Spinel ZnGa2O4 films were grown on c-plane sapphire substrates at the substrate temperature of 400 °C by radio-frequency magnetron sputtering. Post thermal annealing was employed at the annealing temperature of 700 °C in order to enhance their crystal quality. The effect of thermal annealing on the microstructural and optoelectronic properties of ZnGa2O4 films was systematically investigated in various ambiences, such as air, nitrogen, and oxygen. The X-ray diffraction patterns of annealed ZnGa2O4 films showed the crystalline structure to have (111) crystallographic planes. Transmission electron micrographs verified that ZnGa2O4 film annealed under air ambience possesses a quasi-single-crystalline structure. This ZnGa2O4 film annealed under air ambience exhibited a smooth surface, an excellent average transmittance above 82% in the visible region, and a wide bandgap of 5.05 eV. The oxygen vacancies under different annealing ambiences were revealed a substantial impact on the material and photodetector characteristics by X-ray photoelectron spectrum investigations. ZnGa2O4 film exhibits optimal performance as a metal-semiconductor-metal photodetector when annealed under air ambience. Under these conditions, ZnGa2O4 film exhibits a higher photo/dark current ratio of ~104 order, as well as a high responsivity of 2.53 A/W at the bias of 5 V under an incident optical light of 240 nm. These results demonstrate that quasi-single-crystalline ZnGa2O4 films have significant potential in deep-ultraviolet applications.

Trace element immobilization by uranyl minerals in granite-hosted uranium ores: Evidences from the Xiazhuang ore field of Guangdong province, China

2007 ◽  
Vol 95 (1) ◽  
Author(s):  
Long Lu ◽  
Fanrong Chen ◽  
Rodney C. Ewing ◽  
Rucheng Wang
Keyword(s):  
Trace Elements ◽  
Structural Change ◽  
Guangdong Province ◽  
Compositional Variation ◽  
X Ray Diffraction ◽  
Ore Deposit ◽  
Geochemical Behavior ◽  
X Ray ◽  
Significant Structural Change ◽  
Diffraction Patterns

The oxidative alteration of uraninite and the fate of trace elements (Y, LREE, Zr, and Th) in a granite-hosted uranium ore deposit in north Guangdong province, China, were investigated to understand the geochemical behavior of spent UOCompositionally, the cation atomic ratios in uranyl phases often deviate considerably from their respective stoichiometric values as indicated by the nominal formulae, but the compositional variation does not result in significant structural change as indicated by X-ray diffraction patterns. This observation indicates that the structure of U

In Situ Analysis of the Formation of thin TISI2, (>50 nm) Contacts in Submicron Cmos Structures during Rapid Thermal Annealing

1995 ◽  
Vol 402 ◽  
Author(s):  
L. A. Clevenger ◽  
C. Cabral ◽  
R. A. Roy ◽  
C. Lavoie ◽  
R. Viswanathan ◽  
...  
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
High Speed ◽  
Formation Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Patterned Structures ◽  
Millisecond Time Scale ◽  
Diffraction Patterns

AbstractA detailed in situ study of silicide reactions during rapid thermal annealing of patterned structures was performed to determine the effects of linewidth (0.2 to 1.1 μm), dopants (arsenic, boron or phosphorus) and silicon substrate type (poly-Si or <100>-Si) on the C49 to C54-TiSi2 transformation. A synchrotron x-ray source and a high speed position sensitive detector were used to collect x-ray diffraction patterns of the reacting phases on a millisecond time scale, in situ, during annealing. We demonstrate that most patterned C49-TiSi2 structures (0.2 to 1.1 μm in width, 2 to 4 μm2 in area) will incompletely transform into C54-TiSi2 during rapid thermal annealing. The C49 to C54 transformation ends at about 900°C and further annealing to higher temperatures does not force the remaining C49 to transform into C54. We also observed that the C54 formation temperature increases as the linewidth of the silicide structure decreases. These results are explained by a low density of C54 nuclei in C49 which leads to a one-dimensional growth of C54 grains along the length of the patterned lines. Finally the incorporation of a Mo implant into either poly-Si or <100>-Si before the deposition of titanium is shown to increase the percentage of C49 that transforms into C54 and also to lower the C54 formation temperature.

Electron Microscopy of Shock Loaded Polycrystalline Beryllium

1974 ◽  
Vol 32 ◽  
pp. 506-507 ◽  
Author(s):  
J. M. Galbraith ◽  
L. E. Murr ◽  
A. L. Stevens
Keyword(s):  
Electron Microscopy ◽  
Wave Propagation ◽  
Structural Change ◽  
Single Crystal ◽  
Diffraction Pattern ◽  
Shock Loading ◽  
Slip Systems ◽  
Compression Tests ◽  
X Ray Diffraction ◽  
X Ray

Uniaxial compression tests and hydrostatic tests at pressures up to 27 kbars have been performed to determine operating slip systems in single crystal and polycrystal1ine beryllium. A recent study has been made of wave propagation in single crystal beryllium by shock loading to selectively activate various slip systems, and this has been followed by a study of wave propagation and spallation in textured, polycrystal1ine beryllium. An alteration in the X-ray diffraction pattern has been noted after shock loading, but this alteration has not yet been correlated with any structural change occurring during shock loading of polycrystal1ine beryllium.This study is being conducted in an effort to characterize the effects of shock loading on textured, polycrystal1ine beryllium. Samples were fabricated from a billet of Kawecki-Berylco hot pressed HP-10 beryllium.

Evaluation of Freezing Methods by Low Temperature X-Ray Diffraction

1977 ◽  
Vol 35 ◽  
pp. 330-333
Author(s):  
T. Gulik-Krzywicki ◽  
M.J. Costello
Keyword(s):  
Biological Materials ◽  
Molecular Organization ◽  
X Ray Diffraction ◽  
Glass Capillary ◽  
X Ray ◽  
Rate Dependent ◽  
Before And After ◽  
Freeze Etching ◽  
Diffraction Patterns ◽  
Set Up

Freeze-etching electron microscopy is currently one of the best methods for studying molecular organization of biological materials. Its application, however, is still limited by our imprecise knowledge about the perturbations of the original organization which may occur during quenching and fracturing of the samples and during the replication of fractured surfaces. Although it is well known that the preservation of the molecular organization of biological materials is critically dependent on the rate of freezing of the samples, little information is presently available concerning the nature and the extent of freezing-rate dependent perturbations of the original organizations. In order to obtain this information, we have developed a method based on the comparison of x-ray diffraction patterns of samples before and after freezing, prior to fracturing and replication.Our experimental set-up is shown in Fig. 1. The sample to be quenched is placed on its holder which is then mounted on a small metal holder (O) fixed on a glass capillary (p), whose position is controlled by a micromanipulator.

Examination of Rabbit Fc Crystals

1968 ◽  
Vol 26 ◽  
pp. 140-141
Author(s):  
J. P. Robinson ◽  
P. G. Lenhert
Keyword(s):  
Molecular Weight ◽  
Flat Plate ◽  
Phosphate Buffer ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Neutral Ph ◽  
Small Crystals ◽  
Carbon Coated ◽  
Diffraction Patterns

Crystallographic studies of rabbit Fc using X-ray diffraction patterns were recently reported. The unit cell constants were reported to be a = 69. 2 A°, b = 73. 1 A°, c = 60. 6 A°, B = 104° 30', space group P21, monoclinic, volume of asymmetric unit V = 148, 000 A°3. The molecular weight of the fragment was determined to be 55, 000 ± 2000 which is in agreement with earlier determinations by other methods.Fc crystals were formed in water or dilute phosphate buffer at neutral pH. The resulting crystal was a flat plate as previously described. Preparations of small crystals were negatively stained by mixing the suspension with equal volumes of 2% silicotungstate at neutral pH. A drop of the mixture was placed on a carbon coated grid and allowed to stand for a few minutes. The excess liquid was removed and the grid was immediately put in the microscope.

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