Structure and Optical Properties of CdTe and CdS Thin Films after Hard Ultraviolet Irradiation

The influence of hard ultraviolet radiation on the crystalline structure, surface morphology and optical characteristics of CdS and CdTe semiconductor layers obtained by direct current magnetron sputtering are investigated. It was established that the optical characteristics of the studied films CdS and CdTe are insensitive to hard ultraviolet irradiation. The crystalline structure of the CdS and CdTe layers is changed after irradiation. The period of the lattice for cadmium sulfide films increases from c = 6.77(01) Å to c = 6.78(88) Å, which may be due to the formation of point defects and defective complexes. Decrease the integral FWHM of the peaks on the X-ray diffraction patterns of the layers of CdS and CdTe was observed, due to the increase of the coherent scattering regions as a result in the process of near-surface layers partial recrystallization of the investigated films.

Download Full-text

2D X-ray diffraction and molecular modelling of the crystalline structure of polyesters under uniaxial stress

Polymers and Polymer Composites ◽

10.1177/0967391121998225 ◽

2021 ◽

pp. 096739112199822

Author(s):

Ahmed I Abou-Kandil ◽

Gerhard Goldbeck

Keyword(s):

Crystalline Structure ◽

Molecular Modelling ◽

Three Dimensional ◽

Uniaxial Stress ◽

X Ray Diffraction ◽

X Ray ◽

Wide Range ◽

Modelling Techniques ◽

Diffraction Patterns

Studying the crystalline structure of uniaxially and biaxially drawn polyesters is of great importance due to their wide range of applications. In this study, we shed some light on the behaviour of PET and PEN under uniaxial stress using experimental and molecular modelling techniques. Comparing experiment with modelling provides insights into polymer crystallisation with extended chains. Experimental x-ray diffraction patterns are reproduced by means of models of chains sliding along the c-axis leading to some loss of three-dimensional order, i.e. moving away from the condition of perfect register of the fully extended chains in triclinic crystals of both PET and PEN. This will help us understand the mechanism of polymer crystallisation under uniaxial stress and the appearance of mesophases in some cases as discussed herein.

Download Full-text

The Measurement of Surface-Layer Stresses in a Polycrystalline Glass by Means of X-Ray Diffraction

Advances in X-ray Analysis ◽

10.1154/s0376030800011149 ◽

1971 ◽

Vol 15 ◽

pp. 483-488

Author(s):

E.W. Karamer ◽

C.L. Void

Keyword(s):

Production Quality ◽

Glass Product ◽

Powdered Sample ◽

X Ray Diffraction ◽

Surface Layers ◽

Near Surface ◽

X Ray ◽

Stress Effects ◽

Stress Measuring ◽

Glass Compositions

Many glass materials can be made more resistant to failure if the surface layers are in a state of permanent compressive stress. For purposes of monitoring production quality at the factory, as well as to verify compliance with specifications before incorporation into special devices, it is desirable to measure nondestructively this stress magnitude. For those glass compositions in which the stress generating process creates a residual, finely divided, and uniformly dispersed crystalline phase (e.g. “Pyroceram“), a stress measuring technique based upon X-ray diffraction has been adapted and successfully used. Lattice spacings for near-surface crystallites are determined under the stressed conditions present in the final glass product. These lattice spacings are compared with values obtained from a powdered sample of the identical glass composition. In the powdered state the induced stress effects are minimal. Hence, the shift in lattice spacings is a measure of the compressive surface stress level attained in the manufacturing process.

Download Full-text

Texture Inheritance in a Zn Protective Layer

Materials Science Forum ◽

10.4028/www.scientific.net/msf.443-444.189 ◽

2004 ◽

Vol 443-444 ◽

pp. 189-192 ◽

Cited By ~ 1

Author(s):

Jan T. Bonarski

Keyword(s):

Protective Layer ◽

Incident Beam ◽

Layered Structures ◽

Point Of View ◽

X Ray Diffraction ◽

Surface Layers ◽

Near Surface ◽

X Ray ◽

Diffraction Geometry ◽

Information Depth

Crystallographic texture is one of frequently investigated properties of near-surface regions. From the application point of view, the inheritance effect of the crystallographic orientation of a substrate is important for layered structures. The investigation of the texture of layered structures or gradient materials by means of X-ray diffraction back-reflection pole figure measurements requires a control of the information depth. Such measurements at a controlled information depth can be achieved by means of non-symmetrical diffraction geometry, employing a constant value of falling angle of the incident beam. Thus, the texture of near-surface layers with a defined thickness can be examined, as in tomographic techniques. In this work, the method of texture analysis based on a controlled information depth was applied to the investigation of the texture inheritance of a Zn protective layer on deep drawing steel. Moreover, the crystallographic relations between the texture of substrate and deposited layer, termed as texture inheritance, were considered.

Download Full-text

Aging Processes in Implanted Fluorine Ions and Laser Irradiated Films of LaGa:YIG

Фізика і хімія твердого тіла ◽

10.15330/pcss.20.2.202-207 ◽

2019 ◽

Vol 20 (2) ◽

pp. 202-207

Author(s):

B.K. Ostafiychuk ◽

I.P. Yaremiy ◽

S.I. Yaremiy ◽

M.M. Povkh ◽

L.S. Yablon ◽

...

Keyword(s):

Ion Implantation ◽

Laser Irradiation ◽

Crystalline Structure ◽

Laser Annealing ◽

Natural Aging ◽

Surface Layers ◽

Near Surface ◽

Maximum Deformation ◽

Garnet Films ◽

Fluorine Ions

Based on the results of X-ray structural analysis, changes in the crystalline structure during natural aging and laser annealing, which occurred in near-surface layers of epitaxial films of LaGa-substituted Iron-Yttrium Garnet, implanted by F+ ions, were studied. The processes that occur during the ion implantation by F+ in ferrite-garnet films, and the processes that accompany the low-temperature aging of ion-implanted films are considered. From the experimental rocking curves, obtained immediately after ion implantation, after the laser irradiation and after several years, strain profiles were determined. Two stages in the changes of the crystalline structure of the nearsurface disturbed layer over time are revealed. During the first of them, the maximum deformation in the ionimplanted layer increased slightly, and on the second it decreased. It was established that the results of laser annealing and natural aging of near-surface layers implanted by F+ ions and laser irradiated LaGa:YIG films depend on the direction from which laser irradiation occurred. However, the result of their total exposure does not depend on the side of laser irradiation.

Download Full-text

New approach to stress analysis based on grazing-incidence X-ray diffraction

Journal of Applied Crystallography ◽

10.1107/s0021889801005404 ◽

2001 ◽

Vol 34 (4) ◽

pp. 427-435 ◽

Cited By ~ 62

Author(s):

S. J. Skrzypek ◽

A. Baczmański ◽

W. Ratuszek ◽

E. Kusior

Keyword(s):

Residual Stresses ◽

Grazing Incidence ◽

Sample Surface ◽

X Ray Diffraction ◽

Surface Layers ◽

Near Surface ◽

X Ray ◽

Tin Coatings ◽

Diffraction Geometry ◽

Destructive Measurement

A new development in the determination of residual stresses in thin surface layers and coatings is presented. The procedure, based on the grazing-incidence X-ray diffraction geometry (referred to here as the `g-sin2 ψ' geometry), enables non-destructive measurement at a chosen depth below the sample surface. The penetration depth of the X-ray radiation is well defined and does not change during the experiment. The method is particularly useful for the analysis of non-uniform stresses in near-surface layers. The g-sin2 ψ geometry was applied for measurements of the residual stresses in TiN coatings. Anisotropic diffraction elastic constants of textured material were used to determine the stress value from the measured lattice strains. A new method of data treatment enables reference-free measurements of residual stresses.

Download Full-text

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

Nanomaterials ◽

10.3390/nano11092316 ◽

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.

Download Full-text

Investigation of the near-surface matter density radial distribution in the skin explosion of cylindrical conductors

Journal of Physics Conference Series ◽

10.1088/1742-6596/2064/1/012011 ◽

2021 ◽

Vol 2064 (1) ◽

pp. 012011

Author(s):

I M Datsko ◽

N A Labetskaya ◽

V A Vankevich

Keyword(s):

Radial Distribution ◽

Visible Range ◽

Initial Radius ◽

Surface Plasma ◽

X Ray Diffraction ◽

Near Surface ◽

X Ray ◽

Conductor Surface ◽

Diffraction Patterns ◽

Cylindrical Conductors

Abstract Investigations of the near-surface plasma formation process during skin explosion of cylindrical duralumin and copper conductors in rapidly increasing magnetic fields with their induction up to 500 T were carried out. The formation of plasma on the conductor surface was recorded by its glow in the visible range using a four-frame optical camera with an exposure time of each frame of 3 ns. The internal structure of the surface plasma, the assessment of the density of matter in it and its radial distribution were investigated using radiography pictures obtained by X-ray transmission with hv > 0.8 keV, which is formed at the “hot point” of the X-pinch. The dependences of the load substance density on its radius were determined and constructed from the obtained X-ray diffraction patterns at different points in time from the beginning of the current. So at 216 ns at a radius of 1.8 mm of a duralumin conductor with an initial radius of 1.485 mm, the density of the substance is estimated to be 0.0068 g/cm3.

Download Full-text

Effect of Colloidal Silica Addition and Pre-Coating on the Microstructure Change of Cathode Copper Electrodeposited Film

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.3931 ◽

2005 ◽

Vol 475-479 ◽

pp. 3931-3934

Author(s):

Sang Baek Lee ◽

Yung Keun Kim ◽

Byung Il Kim

Keyword(s):

Colloidal Silica ◽

Pure Copper ◽

Copper Deposit ◽

Preferred Orientation ◽

X Ray Diffraction ◽

Sulfate Bath ◽

Structure Surface ◽

Cathode Substrate ◽

Diffraction Patterns ◽

Deposit Film

The crystal structure, surface morphology and preferred orientation of copper electro-deposit were investigated by using sulfate bath with SiO2 suspension and the cathode substrate Au-sputtered. By addition of colloidal silica in copper electrolytic bath and Au pre-coating on substrate, the grains of deposits became fined and uniform and the number of grains were increased. Hardness of copper electrodeposits with colloidal silica increased about 15% in comparison with that of pure copper deposit film. The (111), (200) and (311) planes in the X-ray diffraction patterns were almost swept away, so preferred orientation of copper deposits change from (111) to (110) plane by co-deposit SiO2 and pre-coating the substrate.

Download Full-text