PROBING STRAIN FIELDS ABOUT THIN FILM STRUCTURES USING X-RAY MICRODIFFRACTION

2003 ◽  
Vol 795 ◽  
Author(s):  
C. E. Murray ◽  
I. C. Noyan ◽  
P. M. Mooney ◽  
B. Lai ◽  
Z. Cai
Keyword(s):  
Thin Film ◽  
Characteristic Curve ◽  
Decay Rates ◽  
X Rays ◽  
X Ray Diffraction ◽  
Strain Fields ◽  
X Ray ◽  
Interaction Field ◽  
Rate Of Decay ◽  
Interaction Regions

ABSTRACTThe transfer of strain between thin film features and the underlying substrate represents an important factor in the performance and reliability of semiconductor devices, particularly as the distances between these structures decrease. In order to characterize the interaction regions produced in the substrate due to strained thin film structures, we employed synchrotron-based x-ray diffraction techniques to map the enhanced diffracted intensity of the single-crystal Si substrate at sub-micron resolution. The dynamic-to-kinematic transition observed in the scattering of x-rays from deformed crystals makes this technique extremely sensitive to the amount of substrate deformation as a function of position. Measurements were conducted on 1 μm thick Ni dots evaporated onto Si (111) substrates and 0.24 μm thick, heteroepitaxially grown SiGe strips of various widths on Si (001). The interaction field resolved by the enhanced Si diffracted intensity in the substrate extended up to 100 times the thickness of these features. Although the boundary of the interaction field varied as a function of feature width, a characteristic curve was generated to describe the decay rate of enhanced Si diffracted intensity when the distance from the feature edge is normalized by a mean interaction distance (MID). The rate of decay of the strain fields predicted by traditional treatments of the mechanical interaction between the thin film and substrate did not correspond to the measured decay rates.

scholarly journals Strain mapping on gold thin film buckling and silicon blistering

2005 ◽  
Vol 875 ◽  
Author(s):  
P. Goudeau ◽  
N. Tamura ◽  
G. Parry ◽  
J. Colin ◽  
C. Coupeau ◽  
...  
Keyword(s):  
Thin Film ◽  
X Ray Diffraction ◽  
Crystal Surfaces ◽  
Strain Mapping ◽  
Strain Fields ◽  
Single Crystal Surfaces ◽  
X Ray ◽  
Gold Thin Film ◽  
Compressive Stresses ◽  
Strain Stress

AbstractStress/Strain fields associated with thin film buckling induced by compressive stresses or blistering due to the presence of gas bubbles underneath single crystal surfaces are difficult to measure owing to the microscale dimensions of these structures. In this work, we show that micro Scanning X-ray diffraction is a well suited technique for mapping the strain/stress tensor of these damaged structures.

Surface and Interface Strains Studied by X-Ray Diffraction

1997 ◽  
Vol 505 ◽  
Author(s):  
Koichi. Akimoto ◽  
Takashi Emoto ◽  
Ayahiko Ichimiya
Keyword(s):  
Silicon Substrate ◽  
Silicon Oxide ◽  
Incident Angle ◽  
Surface Strain ◽  
Native Oxide ◽  
X Rays ◽  
X Ray Diffraction ◽  
Strain Fields ◽  
X Ray ◽  
Surface And Interface

ABSTRACTWe have developed a technique of X-ray diffraction in order to measure strain fields near semiconductor surface and interface. The diffraction geometry is using the extremely asymmetric Bragg-case bulk reflection of a small incident angle to the surface and a large angle exiting from the surface. The incident angle of the X-rays is set near critical angle of total reflection by tuning X-ray energy of synchrotron radiation at the Photon Factory, Japan. For thermally grown-silicon oxide/Si(100) interface, the X-ray intensity of the silicon substrate 311 reflection has been measured. From comparison of the full width at half maxima (FWHM) of X-ray rocking curves of various thickness of silicon oxides, it has been revealed that silicon substrate lattice is highly strained in the thin ( less than about 5 nm) silicon oxide/silicon system. In order to know the original silicon surface strain, we have also performed the same kind measurements in the ultra-high vacuum chamber. A clean Si(l 11) 7×7 surface gives sharper X-ray diffraction peak than that of the native oxide/Si(l 11) system. From these measurements, it is concluded that the thin silicon oxide film itself gives strong strain fields to the silicon substrates, which may be the reason of the existence of the structural transition layer at the silicon oxide/Si interface.

Surface and Ultra-Thin Film Characterization by Grazing-Incidence Asymmetric Bragg Diffraction

1989 ◽  
Vol 33 ◽  
pp. 91-100 ◽  
Author(s):  
T. C. Huang
Keyword(s):  
Thin Film ◽  
Diffraction Analysis ◽  
Grazing Incidence ◽  
Bragg Diffraction ◽  
Dead Layer ◽  
X Rays ◽  
X Ray Diffraction ◽  
X Ray ◽  
Depth Profiles ◽  
Radiation Sources

AbstractAn effective technique using grazing-incidence X-rays and asymmetric-Bragg diffraction (GIABD) for the characterization of crystalline phases on surfaces and structural depth-profiles in thin films is described. The application of the GIABD using both X-ray and synchrotron radiation sources for the analysis of an iron-oxide magnetic thin film previously reported to have an unexpected magnetically-dead layer is discussed. The X-ray diffraction analysis using the GIABD and the conventional θ-2θ scanning techniques detected an anti-ferromagnetic hexagonal α-Fe2O3 on the surface and a ferromagnetic tetragonal γ-Fe2O3 in the bulk of the film, respectively. The synchrotron diffraction analysis using incident angles below and above the critical angle of total reflection quantitatively determined the structural depth-profiles of α-Fe2O3 and γ-Fe2O3 in the film.

SURFACE AND INTERFACE STRAINS REVEALED BY X-RAY DIFFRACTION

1999 ◽  
Vol 06 (06) ◽  
pp. 963-966 ◽  
Author(s):  
KOICHI AKIMOTO ◽  
TAKASHI EMOTO ◽  
YUYA ISHIKAWA ◽  
AYAHIKO ICHIMIYA
Keyword(s):  
Silicon Substrate ◽  
Strain Field ◽  
Theoretical Calculations ◽  
Incident Angle ◽  
Experimental Results ◽  
Lattice Expansion ◽  
X Rays ◽  
X Ray Diffraction ◽  
Strain Fields ◽  
X Ray

We measured strain fields near semiconductor surface by X-ray diffraction. The diffraction geometry was using the extremely asymmetric Bragg-case bulk reflection of a small incident angle to the surface and a large angle exiting from the surface. The incident angle of the X-rays was set near critical angle of total reflection by tuning X-ray energy of synchrotron radiation. The X-ray intensity of the silicon substrate 311 reflection was measured to study a Si(111) surface in the ultrahigh vacuum chamber. A clean Si (111)-(7 × 7) surface was found to give a sharper X-ray diffraction peak than that of the native oxide/Si(111) system. By comparison of experimental results and theoretical calculations, it was concluded that the thin silicon oxide film itself gives strong strain fields to the silicon substrates of lattice expansion toward the [311] direction. The strain fields at the Al- and Ag- induced [Formula: see text] surface reconstruction on the Si(111) substrate were also measured. By comparison of experimental results and theoretical calculations, Al-induced reconstruction was suggested to give a strain field to the silicon substrate of lattice expansion toward the [311] direction, whereas Ag-induced reconstruction was suggested to give a strain field to the silicon substrate of lattice compression toward the [311] direction.

Examination of CoNiCu thin films by using XRF and XRD

2014 ◽  
Vol 92 (5) ◽  
pp. 435-439 ◽  
Author(s):  
Ö. Söğüt ◽  
Ç. Dönük ◽  
G. Apaydın ◽  
Ö.F. Bakkaloğlu
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
X Rays ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Radioisotope Source ◽  
Surface Morphologies ◽  
Xrf Spectroscopy ◽  
Fcc Structure

A series of thin films of CoNiCu and NiCu produced using the electrodeposition method have been examined using X-ray fluorescence (XRF), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Energy dispersive XRF spectroscopy was used to determine the concentrations of the atomic percentage in these films. CoNiCu and NiCu thin film samples were excited by gamma rays with 59.5 keV energy photons from 100 mCi 241Am radioisotope source. K X-rays emitted by samples were counted by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. Structural analyses of these films have been done using the XRD technique and thin films were found to have a face-centred cubic (fcc) structure. In addition, surface morphologies of the films have been analysed by SEM. If one examines the SEM images of thin film samples, it can be seen that these elements have been homogeneously distributed in the samples of the thin films.

X-ray diffraction properties of curved crystal diffractors

1992 ◽  
Vol 50 (2) ◽  
pp. 1734-1735
Author(s):  
W. Z. Chang ◽  
D. B. Wittry
Keyword(s):  
Diffraction Theory ◽  
X Rays ◽  
Diffraction Image ◽  
X Ray Diffraction ◽  
Rocking Curve ◽  
X Ray ◽  
Bent Crystal ◽  
Diffraction Geometry ◽  
Crystal Parameter ◽  
Quantitative Procedure

Since Du Mond and Kirkpatrick first discussed the principle of a bent crystal spectrograph in 1930, curved single crystals have been widely utilized as spectrometric monochromators as well as diffractors for focusing x rays diverging from a point. Curved crystal diffraction theory predicts that the diffraction parameters - the rocking curve width w, and the peak reflection coefficient r of curved crystals will certainly deviate from those of their flat form. Due to a lack of curved crystal parameter data in current literature and the need for optimizing the choice of diffraction geometry and crystal materials for various applications, we have continued the investigation of our technique presented at the last conference. In the present abstract, we describe a more rigorous and quantitative procedure for measuring the parameters of curved crystals.The diffraction image of a singly bent crystal under study can be obtained by using the Johann geometry with an x-ray point source.

Problems in Thin-Film X-ray Quantification

1990 ◽  
Vol 48 (2) ◽  
pp. 458-459
Author(s):  
J N Chapman ◽  
W A P Nicholson
Keyword(s):  
Thin Film ◽  
Specimen Thickness ◽  
X Rays ◽  
Characteristic Peak ◽  
Local Composition ◽  
X Ray ◽  
Measured Ratio ◽  
Path Lengths ◽  
Composition Changes

Energy dispersive x-ray microanalysis (EDX) is widely used for the quantitative determination of local composition in thin film specimens. Extraction of quantitative data is usually accomplished by relating the ratio of the number of atoms of two species A and B in the volume excited by the electron beam (nA/nB) to the corresponding ratio of detected characteristic photons (NA/NB) through the use of a k-factor. This leads to an expression of the form nA/nB = kAB NA/NB where kAB is a measure of the relative efficiency with which x-rays are generated and detected from the two species.Errors in thin film x-ray quantification can arise from uncertainties in both NA/NB and kAB. In addition to the inevitable statistical errors, particularly severe problems arise in accurately determining the former if (i) mass loss occurs during spectrum acquisition so that the composition changes as irradiation proceeds, (ii) the characteristic peak from one of the minority components of interest is overlapped by the much larger peak from a majority component, (iii) the measured ratio varies significantly with specimen thickness as a result of electron channeling, or (iv) varying absorption corrections are required due to photons generated at different points having to traverse different path lengths through specimens of irregular and unknown topography on their way to the detector.

Palladium Nanowire Thin Films via Template Growth

2003 ◽  
Vol 775 ◽  
Author(s):  
Donghai Wang ◽  
David T. Johnson ◽  
Byron F. McCaughey ◽  
J. Eric Hampsey ◽  
Jibao He ◽  
...  
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Thin Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Conductive Substrate ◽  
Palladium Nanowires ◽  
Efficient Route ◽  
Silica Thin Film

AbstractPalladium nanowires have been electrodeposited into mesoporous silica thin film templates. Palladium continually grows and fills silica mesopores starting from a bottom conductive substrate, providing a ready and efficient route to fabricate a macroscopic palladium nanowire thin films for potentially use in fuel cells, electrodes, sensors, and other applications. X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicate it is possible to create different nanowire morphology such as bundles and swirling mesostructure based on the template pore structure.

scholarly journals Deep learning for visualization and novelty detection in large X-ray diffraction datasets

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Lars Banko ◽  
Phillip M. Maffettone ◽  
Dennis Naujoks ◽  
Daniel Olds ◽  
Alfred Ludwig
Keyword(s):  
Thin Film ◽  
Crystal Structure ◽  
Artificial Intelligence ◽  
Deep Learning ◽  
Novelty Detection ◽  
Structural Similarity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns ◽  
Post Hoc

AbstractWe apply variational autoencoders (VAE) to X-ray diffraction (XRD) data analysis on both simulated and experimental thin-film data. We show that crystal structure representations learned by a VAE reveal latent information, such as the structural similarity of textured diffraction patterns. While other artificial intelligence (AI) agents are effective at classifying XRD data into known phases, a similarly conditioned VAE is uniquely effective at knowing what it doesn’t know: it can rapidly identify data outside the distribution it was trained on, such as novel phases and mixtures. These capabilities demonstrate that a VAE is a valuable AI agent for aiding materials discovery and understanding XRD measurements both ‘on-the-fly’ and during post hoc analysis.

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