<title>Synchrotron white beam x-ray topography characterization of structural defects in microgravity and ground-based CdZnTe crystals</title>

AbstractDefect structures in (111) 3C-SiC single crystals, grown using the Baikov technique, have been studied using Synchrotron White Beam X-ray Topography (SWBXT). The major types of defects include complex growth sector boundary structures, double positioning twins, stacking faults on { 111 } planes, inclusions and dislocations (including growth dislocations and partial dislocations bounding stacking faults). Detailed stacking fault and double positioning twin configurations are determined using a combination of Nomarski interference microscopy, SEM and white beam x-ray topography in both transmission and reflection geometries. Possible defect generation phenomena are discussed.

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Characterization of Defect Structures in SiC Single Crystals Using Synchrotron X-Ray Topography

MRS Proceedings ◽

10.1557/proc-307-249 ◽

1993 ◽

Vol 307 ◽

Cited By ~ 12

Author(s):

S. Wang ◽

M. Dudley ◽

C. Carter ◽

D. Asbury ◽

C. Fazit

Keyword(s):

Detailed Analysis ◽

Single Crystals ◽

Basal Plane ◽

Defect Structures ◽

Dislocation Generation ◽

Screw Dislocations ◽

X Ray ◽

White Beam

ABSTRACTSynchrotron white beam X-ray topography has been used to characterize defect structures in 6H-SiC wafers grown on (0001) seeds. Two major types of defects are observed: super screw dislocations approximately perpendicular to the basal plane and dislocation networks lying in the basal plane. The super screw dislocations, which have open cores, are growth dislocations. These dislocations act as sources and/or sinks for the glide dislocation networks. Detailed analysis and discussion of dislocation generation phenomena and Burgers vectors will be presented.

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Structural Defect Studies of Semiconductor Crystals with Laue Topography

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.178-179.360 ◽

2011 ◽

Vol 178-179 ◽

pp. 360-365 ◽

Cited By ~ 2

Author(s):

Alexander Gröschel ◽

Johannes Will ◽

Christoph Bergmann ◽

Hannes Grillenberger ◽

Stefan Eichler ◽

...

Keyword(s):

High Energy ◽

Structural Defects ◽

Dislocation Network ◽

X Ray ◽

Gaas Wafer ◽

Semiconductor Crystals ◽

White Beam ◽

Oxygen Precipitates ◽

Si Wafer

A defocused Laue diffractometer setup operating with the white beam of a high energy X-ray tube has been used for a topographic visualization of structural defects in semiconductor wafers. The laboratory white beam X-ray topograph of a Czochralski Si wafer with oxygen precipitates grown in an annealing process is compared to a μPCD image. Further, the dislocation network in a VGF GaAs wafer is studied under thermal annealing up to 1140°C and the in-situ capability of the setup is demonstrated.

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Investigation of Semiconductor Heterostructures by White Beam Synchrotron X-Ray Topography in Grazing Bragg-Laue and Conventional Bragg Geometries

Advances in X-ray Analysis ◽

10.1154/s0376030800008892 ◽

1991 ◽

Vol 35 (A) ◽

pp. 247-253

Author(s):

G.-D. Yao ◽

J. Wu ◽

T. Fanning ◽

M. Dudley

Keyword(s):

Penetration Depth ◽

Grazing Incidence ◽

Semiconductor Heterostructures ◽

Misfit Dislocations ◽

Strained Layers ◽

X Ray ◽

Main Reflection ◽

White Beam ◽

Topographic Imaging

AbstractWhite beam synchrotron X-ray topography has been applied both to the characterization of two semiconductor heterostructures, GaAs/Si and InxGa1-xAs/GaAs strained layers, and a substrate to be used for growing semiconductor epilayers, Cd1-xZnxTe. In the case of the heterostructures, misfit dislocations were observed using depth sensitive X-ray topographic imaging in grazing incidence Bragg-Laue geometries. The X-ray penetration depth, which can be varied from several hundreds of angstroms to hundreds of micrometers by rotating about the main reflection vector, which in this specific case was (355), is governed by kinernatical theory. This is justified by comparing dislocation contrast and visibility with the extent of the calculated effective misorientalion field in comparison to the effective X-ray penetration depth. For the case of Cd1-xZnxTe, twin configurations are observed, and their analysis is presented.

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Synchrotron White Beam Topography Studies of Screw Dislocations in 6H-Sic Single Crystals

MRS Proceedings ◽

10.1557/proc-375-281 ◽

1994 ◽

Vol 375 ◽

Cited By ~ 7

Author(s):

S. Wang ◽

M. Dudley ◽

C. H. Carter ◽

V. F. Tsvetkov ◽

C. Fazi

Keyword(s):

Single Crystals ◽

Structural Defects ◽

Device Performance ◽

Topographic Image ◽

X Ray Diffraction ◽

Screw Dislocations ◽

X Ray ◽

White Beam ◽

Line Defects ◽

Kinematical Theory

AbstractSynchrotron white beam X-ray topography, along with optical microscopy and scanning electron microscopy, has been used to characterize structural defects which are potentially detrimental to device performance in PVT 6H-SiC single crystals. Line defects running along the [0001] axis, known as “micropipes”, were studied extensively. Detailed analysis of topographic image contrast associated with “micropipes”, based on the kinematical theory of X-ray diffraction, established that the so-called “micropipes” are screw dislocations with large Burgers vectors.

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Characterization of SiC using Synchrotron White Beam X-ray Topography

Materials Science Forum ◽

10.4028/www.scientific.net/msf.338-342.431 ◽

2000 ◽

Vol 338-342 ◽

pp. 431-436 ◽

Cited By ~ 30

Author(s):

Michael Dudley ◽

X. Huang

Keyword(s):

X Ray ◽

White Beam

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High-Resolution X-Ray Characterization of Amorphous Semiconductor Multilayers

MRS Proceedings ◽

10.1557/proc-149-711 ◽

1989 ◽

Vol 149 ◽

Cited By ~ 5

Author(s):

P. D. Persans ◽

A. F. Ruppert ◽

B. Abeles ◽

G. Hughes ◽

K. S. Liang

Keyword(s):

Surface Roughness ◽

High Resolution ◽

Layer Thickness ◽

Dynamical Theory ◽

Amorphous Semiconductor ◽

Structural Defects ◽

X Ray Diffraction ◽

X Ray

ABSTRACTWe discuss high-resolution x-ray diffraction measurements on a-Si:H/a-Ge:H periodic amorphous multilayers. Analysis of the data using the dynamical theory yields information on layer thicknesses and densities, interface and surface roughness, and structural defects such as layer thickness fluctuations.

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Characterization of Defect Structures in Lely 6H-SiC Single Crystals Using Synchrotron White Beam X-Ray Topography

MRS Proceedings ◽

10.1557/proc-375-313 ◽

1994 ◽

Vol 375 ◽

Cited By ~ 4

Author(s):

W. Huang ◽

S. Wang ◽

M. Dudley ◽

P. Neudeck ◽

J. A. Powell ◽

...

Keyword(s):

Single Crystals ◽

Basal Plane ◽

Stacking Faults ◽

Defect Structures ◽

Dislocation Generation ◽

X Ray ◽

Partial Dislocations ◽

White Beam ◽

Generation Mechanisms

AbstractDefect structures in Lely SiC single crystals have been studied using synchrotron white beam X-ray topography. Basal plane dislocations and stacking faults probably generated during post-growth cooling are clearly revealed. For both perfect dislocations and partial dislocations bounding the stacking faults, Burgers vectors and line directions are determined from contrast extinction analysis as well as projected direction analysis on different topographic images. The fault planes and fault vectors of the stacking faults were determined using contrast extinction analysis. Possible dislocation generation mechanisms are briefly discussed.

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