Effective Depth of X-Ray Penetration and Its Orientation Dependence

1989 ◽  
pp. 215-221 ◽  
Author(s):  
I. Tomov
Keyword(s):  
Orientation Dependence ◽  
X Ray ◽  
Effective Depth

Voltage and Orientation Dependence of Characteristic X-Ray Production in Thin Crystals

1985 ◽  
Vol 43 ◽  
pp. 414-415
Author(s):  
G. Thomas ◽  
K. M. Krishnan ◽  
Y. Yokota ◽  
H. Hashimoto
Keyword(s):  
Standing Wave ◽  
Incident Beam ◽  
Orientation Dependence ◽  
Incident Plane Wave ◽  
Crystalline Materials ◽  
X Ray ◽  
Incident Plane ◽  
Crystal Unit Cell ◽  
Beam Orientation ◽  
Acceleration Voltage

For crystalline materials, an incident plane wave of electrons under conditions of strong dynamical scattering sets up a standing wave within the crystal. The intensity modulations of this standing wave within the crystal unit cell are a function of the incident beam orientation and the acceleration voltage. As the scattering events (such as inner shell excitations) that lead to characteristic x-ray production are highly localized, the x-ray intensities in turn, are strongly determined by the orientation and the acceleration voltage. For a given acceleration voltage or wavelength of the incident wave, it has been shown that this orientation dependence of the characteristic x-ray emission, termed the “Borrmann effect”, can also be used as a probe for determining specific site occupations of elemental additions in single crystals.

scholarly journals Simulation study towards quantitative X-ray and neutron tensor tomography regarding the validity of linear approximations of dark-field anisotropy

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jonas Graetz
Keyword(s):  
Simulation Study ◽  
Full Range ◽  
Dark Field ◽  
Orientation Dependence ◽  
Field Tensor ◽  
Axis Orientation ◽  
X Ray ◽  
Tensor Tomography ◽  
Order Of Magnitude ◽  
Linear Contrast

AbstractTensor tomography is fundamentally based on the assumption of a both anisotropic and linear contrast mechanism. While the X-ray or neutron dark-field contrast obtained with Talbot(-Lau) interferometers features the required anisotropy, a preceding detailed study of dark-field signal origination however found its specific orientation dependence to be a non-linear function of the underlying anisotropic mass distribution and its orientation, especially challenging the common assumption that dark-field signals are describable by a function over the unit sphere. Here, two approximative linear tensor models with reduced orientation dependence are investigated in a simulation study with regard to their applicability to grating based X-ray or neutron dark-field tensor tomography. By systematically simulating and reconstructing a large sample of isolated volume elements covering the full range of feasible anisotropies and orientations, direct correspondences are drawn between the respective tensors characterizing the physically based dark-field model used for signal synthesization and the mathematically motivated simplified models used for reconstruction. The anisotropy of freely rotating volume elements is thereby confirmed to be, for practical reconstruction purposes, approximable both as a function of the optical axis’ orientation or as a function of the interferometer’s grating orientation. The eigenvalues of the surrogate models’ tensors are found to exhibit fuzzy, yet almost linear relations to those of the synthesization model. Dominant orientations are found to be recoverable with a margin of error on the order of magnitude of 1$$^{\circ }$$ ∘ . Although the input data must adequately address the full orientation dependence of dark-field anisotropy, the present results clearly support the general feasibility of quantitative X-ray dark-field tensor tomography within an inherent yet acceptable statistical margin of uncertainty.

A Study of Recrystallization Texture Formation in Cold Rolled Iron Sheets with X-Ray Diffraction Techniques

1970 ◽  
Vol 14 ◽  
pp. 214-230 ◽  
Author(s):  
M. Matsuo ◽  
S. Hayami ◽  
S. Nagashima
Keyword(s):  
Cold Rolling ◽  
Recrystallization Texture ◽  
High Energy ◽  
Orientation Dependence ◽  
Primary Recrystallization ◽  
Texture Formation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Stable Orientation ◽  
Rotational Orientation

AbstractThe possibility that primary recrystallization textures are influenced by local inhomogeneities of deformation induced in the regions of grain boundaries has been confirmed by comparing the cold rolling and the annealing textures of polycrystalline pure irons which were different in the grain size prior to cold rolling. Analyses were made for the effects of deformation on crystals, namely storage of lattice strain and orientation spread, with application of X-ray diffraction techniques, in order to elucidate the role of in homogeneities of deformation on recrystallization texture formation. Apparent correspondence was found between the orientation dependence of stored strain energy and the textural change on recrystallization. This is a scribed to oriented nucleation in high energy blocks, in the case of originally large-grain material in which the effects of inhomogeneities of deformation are small. But discrepancies arise on this basis in originally small - grain material in which the effects of inhomogeneities of deformation are thought to be considerable. The discrepancy is inferred to arise as an effect of local inhomogeneities of deformation, from the change in the trend of rotational orientation spreads from, a stable orientation and the extent of development of potential nuclei of recrystallization at high energy blocks in the orientation spreads. The change is considered to give rise to the variation in amount of microstrain distribution, which is expressed in recovery characteristics of lattice strains and in the dependence of microstrains on the column length as analyzed by following the procedure of Warren-Averbach.

C49-TiSi2 Epitaxial Orientation Dependence of the C49-to-C54 Phase Transformation Rate

1998 ◽  
Vol 514 ◽  
Author(s):  
T. Nakamura ◽  
K. Ikeda ◽  
H. Tomita ◽  
S. Komiya ◽  
K. Nakajima
Keyword(s):  
Phase Transformation ◽  
Epitaxial Growth ◽  
Grazing Incidence ◽  
Orientation Dependence ◽  
Transformation Rate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Rapid Transformation

ABSTRACTEffects of the C49-TiSi2 epitaxial orientation on the C49-to-C54 phase transformation rate have been studied for samples with different pre-amorphization implantation (PAI) conditions. The C49 epitaxial orientation to the Si(001) substrate is characterized by use of grazing-incidence X-ray diffraction (GIXD) measurements. We found that the PAl treatment suppresses the epitaxial growth of C49-TiSi2 on Si(001) substrates and the poorer orientational alignment of C49-TiSi2 causes a more rapid transformation to C54-TiSi2. We believe this suppression of epitaxial alignment is a possible mechanism to understand the effect of the PAl treatment on the C49-C54 transformation.

Orientation Dependence Of Surface Passivation For Semi-Insulating Gaas

1996 ◽  
Vol 421 ◽  
Author(s):  
I.P. Koutzarov ◽  
C.H. Edirisinghe ◽  
H.E. Ruda ◽  
L.Z. Jedral ◽  
Q. Liu ◽  
...  
Keyword(s):  
Band Gap ◽  
Surface Passivation ◽  
Dielectric Film ◽  
Surface Recombination ◽  
Orientation Dependence ◽  
Film Deposition ◽  
Surface Recombination Velocity ◽  
Strong Increase ◽  
X Ray ◽  
Recombination Velocity

AbstractWe report on the orientation dependence ((100), (110) and (111) ) of photoluminescence (PL), photoreflectance (PR) and Surface Photo-Voltage (SPV) for sulfur passivated bulk semiinsulating (SI) GaAs. Near band gap PL peak intensities (bound-exciton and acceptor-related) were enhanced following (NH4)2S or S2Cl2 treatment of GaAs for all orientations. The reduction of surface recombination velocity (from PL data) was orientation dependent and especially pronounced for the case of (111)A and (111)B orientations. The effect of thin dielectric layers deposited on S-treated surfaces was also investigated, particularly for (100) and (111)A orientations. SPV data shows a strong increase in the above band gap signal after both Streatment and dielectric film deposition, which was higher than that measured for only S-treated surfaces. PR data showed an increase in the interfacial electric field following deposition of dielectric film. The results of absolute S-surface coverage measurements using particle-induced X-ray emission measurements were correlated with the optical characteristics.

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