Influence of Surface Relaxation on X-Ray Topographic Imaging of Interfacial Dislocations in Heterosystems.

1990 ◽  
Vol 209 ◽  
Author(s):  
Gong-Da Yao ◽  
Jun Wu ◽  
Michael Dudley ◽  
Vijay Shastry ◽  
Peter Anderson
Keyword(s):  
Surface Relaxation ◽  
X Ray ◽  
Relaxation Effects ◽  
Single Crystal Films ◽  
Crystal Films ◽  
Interfacial Dislocations ◽  
Depth Sensitivity ◽  
Edge Dislocations ◽  
Topographic Imaging ◽  
Laue Geometry

ABSTRACTThe influence of surface relaxation on the imaging of dislocations in thin single crystal films, using white beam synchrotron radiation topography in grazing Bragg-Laue geometry, has been assessed. The predicted visibility of dislocation images on grazing Bragg- Laue topographs, for the particular case of interfacial edge dislocations in a GaAs/Si heterostructure, is shown to be strongly influenced. Agreement between predicted and observed visibility could only be obtained by incorporating the surface relaxation effects, which thus strongly influence the depth sensitivity of the technique, i.e. the ability to pinpoint the depth of a dislocation. Dislocation image widths are also influenced by these effects.

Influence of surface relaxation on the contrast of threading edge dislocations in synchrotron X-ray topographs under the condition of g · b = 0 and g · b × l = 0

2021 ◽  
Vol 54 (2) ◽  
Author(s):  
Hongyu Peng ◽  
Tuerxun Ailihumaer ◽  
Fumihiro Fujie ◽  
Zeyu Chen ◽  
Balaji Raghothamachar ◽  
...  
Keyword(s):  
Ray Tracing ◽  
Depth Profiling ◽  
Simulation Method ◽  
Surface Relaxation ◽  
X Ray ◽  
Relaxation Effects ◽  
Orientation Contrast ◽  
Relaxation Depth ◽  
Edge Dislocations ◽  
Ray Tracing Simulation

Residual contrast of threading edge dislocations is observed in synchrotron back-reflection X-ray topographs of 4H-SiC epitaxial wafers recorded using basal plane reflections where both g · b = 0 and g · b × l = 0. The ray-tracing simulation method based on the orientation contrast formation mechanism is applied to simulate images of such dislocations by applying surface relaxation effects. The simulated contrast features match the observed features on X-ray topographs, clearly demonstrating that the contrast is dominated by surface relaxation. Depth profiling indicates that the surface relaxation primarily takes place within a depth of 5 µm below the surface.

Influence of Surface Relaxation and Multi-Dislocation Strain Field Interactions on X-ray Topographic Images of Dislocations in Semiconductor Materials

1992 ◽  
Vol 262 ◽  
Author(s):  
Jun Wu ◽  
Thomas Fannin ◽  
Michael Dudley ◽  
Vijay Shastry ◽  
Peter Anderson
Keyword(s):  
Local Stress ◽  
Surface Relaxation ◽  
Contour Analysis ◽  
Displacement Fields ◽  
X Ray ◽  
Relaxation Effects ◽  
Slip Bands ◽  
Sensitive Function ◽  
Local Slip ◽  
Surface Intersections

ABSTRACTAnalysis of the white beam synchrotron x-ray topographic contrast behavior of screw dislocations comprising slip bands in silicon, observed under low absorption conditions, is presented. For both individual and groups of dislocations, observed “Direct Image” contrast at the surface intersections of dislocation lines, on reflections for which g·b=0, could be accounted for using equi-misorientation contour analysis using displacement fields which take surface relaxation effects into account. This contrast is shown to be a sensitive function of the local stress environment. In addition, diffuse area contrast observed within and in the vicinity of slip bands on such reflections is also observed to be very sensitive to long range strain fields associated with adjacent slip bands and other defects in the local slip band environment.

Determination of Strain Distributions in Aluminum Thin Films as a Function of Temperature by the use of Synchrotron Grazing Incidence X-Ray Scattering

1991 ◽  
Vol 239 ◽  
Author(s):  
Ramnath Venkatraman ◽  
Paul R. Besser ◽  
Sean Brennan ◽  
John C. Bravman
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Grazing Incidence ◽  
Surface Relaxation ◽  
Line Broadening ◽  
X Ray ◽  
Relaxation Effects ◽  
X Ray Scattering ◽  
Ray Scattering

ABSTRACTWe have measured elastic strain distributions with depth as a function of temperature in Al thin films of various thicknesses on oxidized silicon using synchrotron grazing incidence X-ray scattering (GIXS). Disregarding minor surface relaxation effects that depend on the film thickness, it is shown that there are no gross strain gradients in these films in the range of temperatures (between room temperature and 400°C) considered. We also observe X-ray line broadening effects, suggesting an accumulation of dislocations on cooling the films, and their annealing out as the films are reheated.

X-Ray studies on single crystal films of BaTiO3

1992 ◽  
Vol 137 (1) ◽  
pp. 33-38 ◽  
Author(s):  
H. Terauchi ◽  
Y. Watanabe ◽  
H. Kasatani ◽  
K. Kamigaki ◽  
T. Terashima ◽  
...  
Keyword(s):  
Single Crystal ◽  
X Ray ◽  
Single Crystal Films ◽  
Crystal Films

Crystal Structures of Epitaxially Grown Fe16N2 Single Crystal Films with Giant Magnetic Moments

1992 ◽  
Vol 263 ◽  
Author(s):  
Matahiro Komuro ◽  
Hiroyuki Hoshiya ◽  
Hiroaki Takahashi ◽  
Katsuya Mitsuoka ◽  
Yutaka Sugita
Keyword(s):  
Crystal Orientation ◽  
Magnetic Moments ◽  
Diffraction Method ◽  
Lattice Parameters ◽  
X Ray Diffraction ◽  
X Ray ◽  
Single Crystal Films ◽  
Crystal Films ◽  
Diffraction Peaks ◽  
Good Agreement

ABSTRACTLattice parameters and crystal orientation for Fe1 6.N2 were determined by an X-ray diffraction method using a three axes goniometer. The lattice parameters of the a-axis and c-axis(a0, c0.) are 5.71 !A and 6.33 !A, respectively. The co corresponds to that of In0, 2,Gao.,s As substrates. Crystal orientation between Fe1 5.N2. films and Ino.,2Gao.,8 As is Fe1 0N2(001)//In0 2.Ga0.2 As(1001) and Fe1 0.N2.(100)//In02Ga0.6As(100). Intensity ratios for these diffraction peaks are in good agreement with calculated values proposed by Jack.

Molecular orientation in single crystal thin films of N-(4-nitrophenyl)-(L)-prolinol

1998 ◽  
Vol 13 (1) ◽  
pp. 131-134 ◽  
Author(s):  
Ligui Zhou ◽  
M. Thakur
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Single Crystal ◽  
Molecular Orientation ◽  
Second Harmonic ◽  
Substrate Surface ◽  
X Ray Diffraction ◽  
X Ray ◽  
Single Crystal Films ◽  
Crystal Films

Thin single crystal films of N-(4-nitrophenyl)-(L)-prolinol (NPP) were prepared using the modified shear method. The surface orientation of the single crystal films was determined by x-ray diffraction and was found to be [101]. Polarized microscopy showed uniform birefringence and complete extinction when the thin film was rotated under crossed polarization, implying single crystal thin films with uniform surface were obtained. The molecular orientation in the NPP thin film was studied by polarized UV-visible and polarized micro-FTIR spectroscopy along with x-ray diffraction. The orientation of the NPP molecules was found to be almost parallel to the plane of the film. This parallel orientation is because of the polar (hydrogen bonding) interaction of the −(OH) and the N=O groups of the NPP molecule with the hydrophilic substrate surface. The results of the second harmonic generation (SHG) measurements are consistent with such a molecular orientation. These results show that the final molecular and crystallographic orientation in the film is determined by its initial molecule-substrate interaction.

X-ray interference effects in thin equiatomic Co-Pt single crystal films

2004 ◽  
Vol 30 (1) ◽  
pp. 42-44
Author(s):  
P. D. Kim ◽  
S. V. Stolyar ◽  
R. S. Iskhakov ◽  
I. A. Turpanov ◽  
V. I. Yushkov ◽  
...  
Keyword(s):  
Single Crystal ◽  
Interference Effects ◽  
X Ray ◽  
Single Crystal Films ◽  
Crystal Films
Sign in / Sign up

Export Citation Format

Share Document