scholarly journals Stress Gradients and Anisotropy in Thin Films

1988 ◽  
Vol 130 ◽  
Author(s):  
Robert M. Fisher ◽  
J. Z. Duan ◽  
Alan G. Fox
Keyword(s):  
Thin Films ◽  
Film Surface ◽  
Diffraction Peak ◽  
X Ray Diffraction ◽  
Thickness Strain ◽  
Strain Gradients ◽  
X Ray ◽  
Stress Gradients ◽  
Diffraction Peaks ◽  
Chromium Films

AbstractIndications that steep through-thickness strain gradients occur in vapour-deposited chromium films stemming from previous observations of film curling during spontaneous delamination from substrates, have been substantiated by analysis and simulation of Bragg X-Ray diffraction peaks. The presence of large through-thickness compressive strains, that increase quadratically with distance from the substrate from about zero at the interface to around 0.8% at the film surface, was deduced by empirical computer matching of diffraction peak shapes.

scholarly journals Strain depth profiles in thin films extracted from in-plane X-ray diffraction

2021 ◽  
Vol 54 (1) ◽  
Author(s):  
Claudia Cancellieri ◽  
Daniel Ariosa ◽  
Aleksandr V. Druzhinin ◽  
Yeliz Unutulmazsoy ◽  
Antonia Neels ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Film Thickness ◽  
Depth Profile ◽  
Film Surface ◽  
Inverse Laplace Transform ◽  
X Ray Diffraction ◽  
X Ray ◽  
Stress Gradients ◽  
Dependent Strain

Thin films generally contain depth-dependent residual stress gradients, which influence their functional properties and stability in harsh environments. An understanding of these stress gradients and their influence is crucial for many applications. Standard methods for thin-film stress determination only provide average strain values, thus disregarding possible variation in strain/stress across the film thickness. This work introduces a new method to derive depth-dependent strain profiles in thin films with thicknesses in the submicrometre range by laboratory-based in-plane grazing X-ray diffraction, as applied to magnetron-sputtering-grown polycrystalline Cu thin films with different thicknesses. By performing in-plane grazing diffraction analysis at different incidence angles, the in-plane lattice constant depth profile of the thin film can be resolved through a dedicated robust data processing procedure. Owing to the underlying intrinsic difficulties related to the inverse Laplace transform of discrete experimental data sets, four complementary procedures are presented to reliably extract the strain depth profile of the films from the diffraction data. Surprisingly, the strain depth profile is not monotonic and possesses a complex shape: highly compressive close to the substrate interface, more tensile within the film and relaxed close to the film surface. The same strain profile is obtained by the four different data evaluation methods, confirming the validity of the derived depth-dependent strain profiles as a function of the film thickness. Comparison of the obtained results with the average in-plane stresses independently derived by the standard stress analysis method in the out-of-plane diffraction geometry validates the solidity of the proposed method.

scholarly journals Annealing-Driven Microstructural Evolution and Its Effects on the Surface and Nanomechanical Properties of Cu-Doped NiO Thin Films

Coatings ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 107 ◽  
Author(s):  
San-Ho Wang ◽  
Sheng-Rui Jian ◽  
Guo-Ju Chen ◽  
Huy-Zu Cheng ◽  
Jenh-Yih Juang
Keyword(s):  
Thin Films ◽  
Photoelectron Spectroscopy ◽  
Annealing Temperature ◽  
Film Surface ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nanomechanical Properties ◽  
Glass Substrates ◽  
Structural Surface ◽  
Diffraction Peaks

The effects of annealing temperature on the structural, surface morphological and nanomechanical properties of Cu-doped (Cu-10 at %) NiO thin films grown on glass substrates by radio-frequency magnetron sputtering are investigated in this study. The X-ray diffraction (XRD) results indicated that the as-deposited Cu-doped NiO (CNO) thin films predominantly consisted of highly defective (200)-oriented grains, as revealed by the broadened diffraction peaks. Progressively increasing the annealing temperature from 300 to 500 °C appeared to drive the films into a more equiaxed polycrystalline structure with enhanced film crystallinity, as manifested by the increased intensities and narrower peak widths of (111), (200) and even (220) diffraction peaks. The changes in the film microstructure appeared to result in significant effects on the surface energy, in particular the wettability of the films as revealed by the X-ray photoelectron spectroscopy and the contact angle of the water droplets on the film surface. The nanoindentation tests further revealed that both the hardness and Young’s modulus of the CNO thin films increased with the annealing temperature, suggesting that the strain state and/or grain boundaries may have played a prominent role in determining the film’s nanomechanical characterizations.

Strain in Epitaxial BaTiO3 Thin Films Prepared by MOCVD

1998 ◽  
Vol 541 ◽  
Author(s):  
S. Chattopadhyay ◽  
A. Teren ◽  
B.W. Wessels
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Full Width Half Maximum ◽  
Diffraction Peak ◽  
Full Width ◽  
Half Maximum ◽  
X Ray Diffraction ◽  
X Ray ◽  
Peak Broadening ◽  
Diffraction Peaks

AbstractThe microstrain in epitaxial BaTiO3 thin films has been investigated using x-ray diffraction. The full width half maximum of the (001) diffraction peaks ranged from 0.12 to 0.49 deg. From the analysis of the angular dependence of the diffraction peak broadening, it is concluded that the broadening is due predominantly to strain. The magnitude of the microstrain decreases sharply with increasing film thickness.

The Microstructure and Electrical Property of Porous Cu Film on Soft PVDF Substrate

2012 ◽  
Vol 472-475 ◽  
pp. 1451-1454
Author(s):  
Xue Hui Wang ◽  
Wu Tang ◽  
Ji Jun Yang
Keyword(s):  
Electrical Properties ◽  
Film Surface ◽  
X Ray Diffraction ◽  
Si Substrate ◽  
X Ray ◽  
Cu Films ◽  
Cu Film ◽  
Diffraction Peaks ◽  
Sputtering Pressure ◽  
Effect Method

The porous Cu film was deposited on soft PVDF substrate by magnetron sputtering at different sputtering pressure. The microstructure and electrical properties of Cu films were investigated as a function of sputtering pressure by X-ray diffraction XRD and Hall effect method. The results show that the surface morphology of Cu film is porous, and the XRD revealed that there are Cu diffraction peaks with highly textured having a Cu-(220) or a mixture of Cu-(111) and Cu-(220) at sputtering pressure 0.5 Pa. The electrical properties are also severely influenced by sputtering pressure, the resistivity of the porous Cu film is much larger than that fabricated on Si substrate. Furthermore, the resistivity increases simultaneously with the increasing of Cu film surface aperture, but the resistivity of Cu film still decreases with the increasing grain size. It can be concluded that the crystal structure is still the most important factor for the porous Cu film resistivity.

Transparent Conductive Cu-In-O Thin Films Deposited by Reactive DC Magnetron Sputtering with Different Targets

2011 ◽  
Vol 239-242 ◽  
pp. 2752-2755
Author(s):  
Fan Ye ◽  
Xing Min Cai ◽  
Fu Ping Dai ◽  
Dong Ping Zhang ◽  
Ping Fan ◽  
...  
Keyword(s):  
Thin Films ◽  
Magnetron Sputtering ◽  
Optical Band Gap ◽  
Diffraction Peak ◽  
X Ray Diffraction ◽  
Dc Magnetron Sputtering ◽  
Flow Rates ◽  
X Ray ◽  
Equal Distance ◽  
Transmittance Curve

Transparent conductive Cu-In-O thin films were deposited by reactive DC magnetron sputtering. Two types of targets were used. The first was In target covered with a fan-shaped Cu plate of the same radius and the second was Cu target on which six In grains of 1.5mm was placed with equal distance between each other. The samples were characterized with scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), UV/VIS spectrophotometer, four-probe measurement etc. SEM shows that the surfaces of all the samples are very smooth. EDX shows that the samples contain Cu, In as well as O, and different targets result in different atomic ratios of Cu to In. A diffraction peak related to rhombohedra-centered In2O3(012) is observed in the XRD spectra of all the samples. For both the two targets, the transmittance decreases with the increase of O2flow rates. The direct optical band gap of all the samples is also estimated according to the transmittance curve. For both the two targets, different O2flow rates result in different sheet resistances and conductivities. The target of Cu on In shows more controllability in the composition and properties of Cu-In-O films.

Effect of Sputtering Pressure on the Formation of Semiconducting Mg2Si Films

2010 ◽  
Vol 663-665 ◽  
pp. 166-169
Author(s):  
Qing Quan Xiao ◽  
Quan Xie ◽  
Ke Jie Zhao ◽  
Zhi Qiang Yu
Keyword(s):  
Film Growth ◽  
Diffraction Peak ◽  
Morphological Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Peak Intensity ◽  
Main Diffraction Peak ◽  
Diffraction Peaks ◽  
Si Films ◽  
Sputtering Pressure

Semiconducting Mg2Si films were fabricated on Si (111) substrates by magnetron sputtering and subsequent annealing, and the effects of sputtering pressure on the Mg2Si film growth were studied. The structural and morphological properties of Mg2Si films were investigated by the means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the Mg2Si (220) main diffraction peak intensity increased and then decreased with the increasing of sputtering pressure. The (220) diffraction peak got its maximum at 3.0 Pa sputtering pressure. The intensity of Mg2Si (200) and (400) diffraction peaks increased rapidly as the sputtering pressure decreased when the pressure was lower than 1.5 Pa. The films prepared at higher sputtering pressure had very irregular microstructures, and the surface of semiconducting Mg2Si films became smoother with the decreasing of the sputtering pressure.

Microbeam X-ray diffraction from twisted lamellar crystals: theory and computer simulation

2009 ◽  
Vol 42 (4) ◽  
pp. 673-680 ◽  
Author(s):  
Valeriy A. Luchnikov ◽  
Dimitri A. Ivanov
Keyword(s):  
Basal Plane ◽  
Peak Position ◽  
Diffraction Peak ◽  
Reciprocal Space ◽  
X Ray Diffraction ◽  
X Ray ◽  
Peak Broadening ◽  
Asymmetric Shape ◽  
Diffraction Peaks ◽  
Lamellar Crystals

The diffraction peak position, width and intensity distribution are calculated for the case of a helicoidally twisted crystalline lamella, both analytically and numerically. It is shown that the diffraction peak broadening depends on the orientation of the corresponding reciprocal-space vector with respect to the helicoid axis and the normal to the lamellar basal plane. The equatorial peaks, which are close to the normal direction to the lamellar basal plane, are characterized by the highest azimuthal width. By contrast, the reflections positioned close to the lamellar surface have the smallest azimuthal width. For non-equatorial peaks in the proximity of the twisting axis the intensity has an unusual asymmetric shape. The shape of the microbeam, as well as its position and direction with respect to the lamella, influences the shape of the diffraction peaks in reciprocal space and their appearance in two-dimensional diffractograms. The proposed approach can be useful, for example, for the interpretation of microbeam diffractograms of banded polymer spherulites.

X-ray Line Broadening Analysis of Tl-Superconducting Films

1989 ◽  
Vol 33 ◽  
pp. 145-151
Author(s):  
M. O. Eatough ◽  
D. S. Ginley ◽  
B. Morosin
Keyword(s):  
Thin Films ◽  
Superconducting Films ◽  
Electron Beam Evaporation ◽  
Superconducting Thin Films ◽  
Line Broadening ◽  
X Ray Diffraction ◽  
X Ray ◽  
Current Densities ◽  
Diffraction Peaks ◽  
Sequential Electron

AbstractSuperconducting thin films (0.3-0.7μm) in the TI-Ca-Ba-Cu-0 system have been prepared on various single crystal substrates by sequential electron beam evaporation followed by appropriate sintering and annealing. Oxygen-annealed films show Tc as high as 110K and critical current densities to 600,000 A/cm2. X-ray diffraction analyses of these films show predominantly the Tl2Ca2Ba2Cu2O10 phase (c-parameter near 36Å), but some also contain up to 50 at% of the Tl2CaBa2Cu2O8 phase (c-parameter near 30Å). The complete absence of hkl reflections other than 00I demonstrates the highly oriented nature of the films as well as the absence of other Tl phases. The diffraction peaks are noticeably broader for the 36Å phase than for the 30Å phase. For a 0.7μm film such broadening is consistent with coherent sizes along the c-axis of 1200 - 1400Å and 500Å, respectively, for the 30Å and 36Å phases, and of strain values near 1.4-1.8 x 10-3 for both phases.

Stress and Texture Analysis in Thin Films and Coatings by X-Ray Diffraction

2006 ◽  
Vol 514-516 ◽  
pp. 1613-1617
Author(s):  
J.C.P. Pina ◽  
Maria José Marques ◽  
J.M.M. dos Santos ◽  
A. Morão Dias
Keyword(s):  
Thin Films ◽  
Crystallographic Texture ◽  
Fiber Texture ◽  
X Ray Diffraction ◽  
X Ray ◽  
Tensile Stresses ◽  
Aluminum Coatings ◽  
Annealing Temperatures ◽  
Diffraction Geometry ◽  
Chromium Films

The thin and textured coatings present a double difficulty for characterization by conventional X-ray diffraction. Their shallow depth reduces the diffracted intensity and allows the interference of the underlying material. Frequently they present a crystallographic texture which limits the number of orientations that provide good intensity and induces anisotropy effects on their mechanical behavior. Reliable results can be determined using diffraction geometry of lowincidence angle. This paper describes the application of the technique to several films, characterized by thicknesses of the order of 1 μm and crystallographic textures. Examples are proposed of chromium films applied by PVD on molybdenum substrates, decorative electroplated coatings, and aluminum coatings used for interconnections in microelectronic circuits. The Cr films are 1.5 μm thick and exhibit a strong <100> fiber texture. The decorative coatings were studied both on the nickel undercoat and in the Cr top layer. Results are presented for chromium where tensile stresses and a <110> fiber texture were observed. The Al films are 1.0 μm thick. Some samples were heattreated at different annealing temperatures. Tensile stresses were always observed, which increase in the annealed samples.

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