STRUCTURE AND PROPERTIES OF NONHYDROGEN GexC1−x FILMS PREPARED BY PLD

2018 ◽  
Vol 25 (07) ◽  
pp. 1950018
Author(s):  
YONG CHENG ◽  
GUOJUN HUANG ◽  
YIMIN LU ◽  
YANLONG GUO ◽  
CHAOWEI MI ◽  
...  
Keyword(s):  
Amorphous Structure ◽  
Xps Analysis ◽  
Pulsed Lasers ◽  
Structure And Properties ◽  
Spectral Measurements ◽  
Infrared Transmission ◽  
Infrared Band ◽  
Germanium Content ◽  
Adhesion Properties ◽  
Germanium Carbide

Nonhydrogen germanium carbide (GexC[Formula: see text]) films were prepared by KrF pulsed lasers deposition (PLD), and the effects of different germanium contents on the microstructures, optical properties and adhesion properties of the GexC[Formula: see text] films were studied. XRD measurements showed that the GexC[Formula: see text] films with different germanium contents were of amorphous structure. XPS analysis showed that the C/Ge atomic ratios of GexC[Formula: see text] films were close to those of corresponding targets. The intensity of Ge3[Formula: see text] peak in the GexC[Formula: see text] films increased and the intensity of C1s peak decreased with the increase of the germanium content. The GexC[Formula: see text] films’ [Formula: see text]C bond contents increased from 46.4% to 69.7%. Ellipsometry and infrared transmission spectral measurements showed that the refractive index of GexC[Formula: see text] films increased from 2.5 to 3.5 at the wavelength of 1[Formula: see text][Formula: see text]m with the increase of germanium content. The extinction coefficient of GexC[Formula: see text] film was of the order of 10[Formula: see text] in the infrared band when the germanium content was less than 10[Formula: see text]at.%. The adhesion tests showed that the adhesion performances of GexC[Formula: see text] films were better when the germanium content increased.

Graded X-ray Optics for Synchrotron Radiation Applications

1998 ◽  
Vol 5 (3) ◽  
pp. 239-245 ◽  
Author(s):  
A. Erko ◽  
M. Veldkamp ◽  
W. Gudat ◽  
N. V. Abrosimov ◽  
S. N. Rossolenko ◽  
...  
Keyword(s):  
Synchrotron Radiation ◽  
Magnetron Sputtering ◽  
Single Crystals ◽  
Theoretical Data ◽  
Lattice Parameter ◽  
Structure And Properties ◽  
Czochralski Technique ◽  
Spectral Measurements ◽  
Optical Elements ◽  
X Ray

Using X-ray diffractometry and spectral measurements, the structure and properties of graded X-ray optical elements have been examined. Experimental and theoretical data on X-ray supermirrors, which were prepared by the magnetron sputtering technique using precise thickness control, are reported. Measurements on graded aperiodic Si1−x Ge x single crystals, which were grown by the Czochralski technique, are also presented. The lattice parameter of such a crystal changes almost linearly with increasing Ge concentration. The measurements indicate that Si1−x Ge x crystals with concentrations up to 7 at.% Ge can be grown with a quality comparable to that of pure Si crystals.

Increasing sp3hybridized carbon atoms in germanium carbide films by increasing the argon ion energy and germanium content

2010 ◽  
Vol 43 (13) ◽  
pp. 135103 ◽  
Author(s):  
C Q Hu ◽  
B Zheng ◽  
J Q Zhu ◽  
J C Han ◽  
W T Zheng ◽  
...  
Keyword(s):  
Germanium Content ◽  
Ion Energy ◽  
Germanium Carbide ◽  
Argon Ion

Effect of Glycerol on Structure and Properties of Silk Fibroin/Pearl Powder Blend Films

2013 ◽  
Vol 796 ◽  
pp. 126-131 ◽  
Author(s):  
Rui Juan Xie ◽  
Meng Zhang
Keyword(s):  
Dissolution Rate ◽  
Silk Fibroin ◽  
Testing Machine ◽  
Amorphous Structure ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
Elongation At Break ◽  
Blend Films ◽  
Universal Testing ◽  
Significant Difference

In the present study, glycerol was used as plasticizer to prepare silk fibroin (SF)/pearl powder (PP) blend films. The effects of amount of glycerol on structure and properties of the films were investigated. The surface morphology was observed with scanning electron microscopy. The structure of films was investigated by X-ray diffraction and thermal analysis. The mechanical properties of the films were measured on a universal testing machine, and the dissolution rate of SF was examined by ultraviolet spectroscopy. The results showed that surface of pure SF films was smooth, but the surface of films containingPP was uneven, particles of PP dispersed in the films. The structure of the film without glycerol was mainly amorphous structure. The structure of the SF in the film was mainly silk I and silk II when the proportion of glycerol added was in the range of 10%- 20%, while the main structure of the SF in the films was silk I when the proportion of glycerol was more than 20%. The dissolution rate of SF in films without glycerol is rather great, while the dissolution rate had a significant decrease by adding glycerol. There was no significant difference in dissolution rates of SF which were all below 1.3% when the proportion of glycerol is 10-40%. The films without glycerol had very small elongation at break. The elongation at break of SF films increased with the increased amount of glycerol. Compared to films without glycerol, there was a significant difference when the proportion of glycerol was greater than 10%. The tensile strength of the films dropped significantly with the increase of glycerol, but there was no significant difference when the proportion of glycerol was greater than 30%. Therefore, the advisable addition percentage of glycerol is 20%.

Effects of Annealing Temperature on the Structure and Properties of TiO2 Nanofilm Materials

2012 ◽  
Vol 531 ◽  
pp. 203-206
Author(s):  
Han Shui Wu ◽  
Ying Lian Wang
Keyword(s):  
Grain Size ◽  
Annealing Temperature ◽  
Anatase Phase ◽  
Rutile Phase ◽  
Amorphous Structure ◽  
Annealing Process ◽  
Structure And Properties ◽  
Glass Substrates ◽  
Quantum Size ◽  
Uv Absorption Spectrum

TiO2 thin films with good performance have been prepared by R.F. magnetron sputtering method on glass substrates. Surface morphology and UV absorption spectrum have been studied by XRD, SEM and UV-Vis scanning spectrophotometer. The influence of annealing temperature has also been discussed. The results show that, the films without annealing process present amorphous structure, the defects density of interior fiber is high and the structure is loose. With the rise of annealing temperature, the grain size increases, porosity decreases, and compactness is enhanced, at the same time, the film turns from anatase phase to rutile phase, quantum size effect is significant, surface energy reduces and absorb edge has red shift.

Structure and Properties of Germanium Carbide Films Prepared by RF Reactive Sputtering inAr/CH4

1997 ◽  
Vol 36 (Part 1, No. 6A) ◽  
pp. 3625-3628 ◽  
Author(s):  
Liu Z. T. ◽  
Zhu J. Z. ◽  
Xu N. K. ◽  
Zheng X. L.
Keyword(s):  
Reactive Sputtering ◽  
Structure And Properties ◽  
Germanium Carbide

XPS Research on SrTiO3-Based Voltage-Sensitive Material

2008 ◽  
Vol 368-372 ◽  
pp. 535-537
Author(s):  
Yu Xing Xu ◽  
Zi Long Tang ◽  
Zhong Tai Zhang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Xps Analysis ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
Sensitive Material ◽  
X Ray ◽  
Average Grain Size ◽  
Scanning Electron

SrTiO3-based voltage-sensitive material was prepared successfully. The structure and properties were investigated using scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. It was observed that the average grain size was greater than 3μm and a cubic perovskite structure was obtained. XPS analysis of oxygen indicated that there existed multiform chemical state oxygen at the surface of the grain. Further researches shown that there were a few [AO12] polyhedrons and many cation vacancies in the material discussed, which demonstrated that a lot of oxygen volatilized and a well-known semiconductivity level was achieved.

Frequency Selective Surface for Infrared Transmission Suppression at Atmospheric Window

2018 ◽  
Vol 937 ◽  
pp. 89-95
Author(s):  
Xiao Li Chen ◽  
Chang Hui Tian ◽  
Zhi Xin Che
Keyword(s):  
Electromagnetic Waves ◽  
Far Infrared ◽  
Black Body ◽  
Frequency Selective Surface ◽  
Infrared Transmission ◽  
Infrared Band ◽  
Infrared Transmittance ◽  
Wide Range ◽  
Potential Applications ◽  
Frequency Selective

A double screen infrared frequency selective surface (FSS) with dual transmission stopbands was proposed and numerically investigated. Simulation results show that the infrared transmittance of the structure is lower than 10% in mid-infrared band (3~5 μm) and far-infrared band (8 ~14 μm).This structure is polarization insensitive to the incident electromagnetic waves. For a wide range of incident angles from 0° to 60°, the infrared transmittance of the structure is still lower than 25% in the band of interest. Compared with black body, the radiation ratio of structure is lower in the MWIR and LWIR ranges. The structure provide the potential applications for infrared stealth.

A DFT-Study of Structure and Properties of Amorphous SiCN

2002 ◽  
Vol 731 ◽  
Author(s):  
Peter Kroll
Keyword(s):  
Bulk Modulus ◽  
Density Functional ◽  
Elevated Temperatures ◽  
Amorphous Structure ◽  
Silicon Carbonitride ◽  
Random Networks ◽  
Structure And Properties ◽  
Functional Methods ◽  
Structures And Properties ◽  
Amorphous Si

AbstractStructures and properties of amorphous silicon carbonitride (a-SiCN) materials are studied using density functional methods. Topologicaly different models of a-SiCN with 112-156 atoms each were generated from continuous alternating random networks. The networks have distinct topologies which result in a different chemical bonding in the investigated structural models. A first model consists of Si-N and Si-C bonds only. For such materials with “anionic” carbon we found the highest bulk modulus. However, the network strain is largely due to the high SiC content, resulting in bond ruputre and redistribution in the amorphous structure. A second model consists of Si-N and C-N bonds only. We found that a tetrahedral coordination of “cationic” carbon in such a compound is unstable at elevated temperatures, as indicated by Car-Parrinello molecular dynamic (CPMD) simulations. A third model consists of amorphous Si3N4 as host structure and a segregation of graphitic C inside a pore. Such a model, although low in density, has an enlarged bulk modulus, comparable to the “anionic” model.

Amorphous structure and properties in laser-clad Ni-Cr-Al coating on Al-Si alloy

1999 ◽  
Author(s):  
Gongying Liang ◽  
T. T. Wong ◽  
J. Y. Su ◽  
C. H. Woo
Keyword(s):  
Amorphous Structure ◽  
Structure And Properties ◽  
Al Coating

scholarly journals Ab Initio Study of Electronic Transport in Cubic-HfO2 Grain Boundaries

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Elena Degoli ◽  
Eleonora Luppi ◽  
Nathalie Capron
Keyword(s):  
Grain Boundaries ◽  
Electronic Transport ◽  
First Principles ◽  
Polycrystalline Material ◽  
Physical Stability ◽  
Amorphous Structure ◽  
Polycrystalline Materials ◽  
Structure And Properties ◽  
Defects And Impurities ◽  
The Impact

In polycrystalline materials the grain boundaries (GBs) are particularly important as they can act as a sink for atom defects and impurities, which may drive structural transformation of the materials and consequently modify their properties. Characterising the structure and properties of GBs is critical for understanding and controlling material property. Here, we investigated how GBs can modify the structural, electronic, and transport properties of the polycrystalline material HfO2. In general, grain boundaries are considered to be detrimental to the physical stability and electronic transport in HfO2. Anyway, studying by first principles the two most stable and common types of GBs, the tilt and the twist, we found substantial differences on the impact they have on the material properties. In fact, while tilt defects create channels of different sizes and shapes in hafnia along which the electronic transport is stronger in relation to leakage current through GBs, twist defects create a sort of amorphous structure that tends to resemble the bulk and which is independent of the number of rotated planes/atoms.

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