Inversion Domain Boundary Dislocations in Heteroepitaxial Films

1988 ◽  
Vol 144 ◽  
Author(s):  
T. T. Cheng ◽  
P. Pirouz ◽  
F. Ernst
Keyword(s):  
Electron Microscope ◽  
Domain Boundary ◽  
Relative Displacement ◽  
Boundary Dislocation ◽  
Fringe Contrast ◽  
Burgers Vector ◽  
Inversion Domain ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Inversion Domain Boundaries

ABSTRACTTransmission electron microscope (TEM) images of inversion domain boundaries (IDB) show fringe contrast, thus indicating a relative displacement between the two adjoining domains. When the IDBs are facetted, different facets may have different displacement fault vectors. This implies that when the facetting changes from one plane to another, there should be a dislocation at the intersection of the planes. This is termed an “inversion domain boundary dislocation” and it will have a Burgers vector b=R1–R2 where R1, and R2 are the fault vectors of the two facets. Experimental results for facetted IDBs and IDB dislocations in SiC grown heteroepitaxially on (001) silicon are presented.

Microstructral Investigations on GaN Films Grown by Laser Induced Molecular Beam Epitaxy

1999 ◽  
Vol 595 ◽  
Author(s):  
H. Zhou ◽  
F. Phillipp ◽  
M. Gross ◽  
H. Schröder
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Threading Dislocations ◽  
Planar Defects ◽  
Sapphire Substrates ◽  
Inversion Domain ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Line Defects ◽  
Inversion Domain Boundaries

AbstractMicrostructural investigations on GaN films grown on SiC and sapphire substrates by laser induced molecular beam epitaxy have been performed. Threading dislocations with Burgers vectors of 1/3<1120>, 1/3<1123> and [0001] are typical line defects, predominantly the first type of dislocations. Their densities are typically 1.5×1010 cm−2 and 4×109 cm−2 on SiC and sapphire, respectively. Additionally, planar defects characterized as inversion domain boundaries lying on {1100} planes have been observed in GaN/sapphire samples with an inversion domain density of 4×109 cm−2. The inversion domains are of Ga-polarity with respect to the N-polarity of the adjacent matrix. However, GaN layers grown on SiC show Ga-polarity. Possible reasons for the different morphologies and structures of the films grown on different substrates are discussed. Based on an analysis of displacement fringes of inversion domains, an atomic model of the IDB-II with Ga-N bonds across the boundary was deduced. High resolution transmission electron microscopy (HRTEM) observations and the corresponding simulations confirmed the IDB-II structure determined by the analysis of displacement fringes.

Inversion Domain Boundaries in GaN Grown on Sapphire

1996 ◽  
Vol 449 ◽  
Author(s):  
L. T. Romano ◽  
J.E. Northrup
Keyword(s):  
Dark Field ◽  
Hydride Vapor Phase Epitaxy ◽  
Dark Field Imaging ◽  
Inversion Domain ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Convergent Beam ◽  
Inversion Domain Boundaries ◽  
Field Imaging ◽  
Beam Diffraction

ABSTRACTInversion domain boundaries (IDBs) in GaN grown on sapphire (0001) were studied by a combination of high resolution transmission electron microscopy, multiple dark field imaging, and convergent beam diffraction. Films grown by molecular beam epitaxy (MBE), metalorganic vapor deposition (MOCVD), and hydride vapor phase epitaxy (HVPE) were investigated and all found to contain IDBs. Inversion domains (IDs) that extended from the surface to the interface were found to be columnar with facets on the {10–10} and {11–20} planes. Other domains ended within the film that formed IDBs on the (0001) and {1–102} planes. The domains were found to grow in clusters and connect at points along the boundary.

A Study Of Domain Boundary Structures In Lead Titanate Single Crystals

1991 ◽  
Vol 238 ◽  
Author(s):  
C. C. Chou ◽  
J. Li ◽  
C. M. Wayman
Keyword(s):  
Electron Microscopy ◽  
Single Crystals ◽  
Lead Titanate ◽  
Mixed Type ◽  
Domain Boundary ◽  
Dynamical Theory ◽  
Fringe Contrast ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Contrast Analysis

ABSTRACTDomain boundary structures of flux-grown poly-domain lead titanate single crystals have been studied using transmission electron microscopy. 90° and 180° domain boundaries were seen in the crystals and were systematically analyzed under various diffraction conditions. Although 90° domain boundaries are supposely δ-type boundaries in BaTiO3, our results show that displacement plays an important role at boundaries and the extreme fringe contrast (EFC) behavior of 90° boundaries is of the mixed type. In the present work, an analysis based upon the two beam dynamical theory was conducted and a rule similar to stacking-fault contrast analysis was established to predict the geometric configuration of a 180° domain boundary using EFC behavior. Examples are given and verified by tilting experiments and electron diffraction. The results are consistent and offer a convenient way to distinguish between 90° and 180° boundaries.

Island Coalescence Induced Substructure Within GaP Epitaxial Layers Grown on (001), (111), (110) and (113) Si

2000 ◽  
Vol 618 ◽  
Author(s):  
V. Narayanan ◽  
S. Mahajan ◽  
K. J. Bachmann ◽  
V. Woods ◽  
N. Dietz
Keyword(s):  
Defect Formation ◽  
Chemical Beam Epitaxy ◽  
Inversion Domain ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Lattice Images ◽  
Tilt Boundaries ◽  
Island Coalescence ◽  
Inversion Domain Boundaries ◽  
Multiple Twinning

ABSTRACTGaP islands grown on selected surfaces of Si and their coalescence behavior have been investigated by transmission electron microscopy. These layers were grown by chemical beam epitaxy. A number of significant observations emerge from this study. First, planar defect formation has been shown to be related to stacking errors on the smaller P-terminated {111} facets of GaP islands. Amongst the four orientations, (111) epilayers have a higher density of stacking faults and first order twins because of more P-terminated {111} facets per island. Second, multiple twinning on exposed {111} facets can produce tilt boundaries and irregular growths when islands coalesce. Third, inversion domain boundaries lying on {110} planes have been shown to form during GaP island coalescence across monatomic steps on (001) Si. Image simulations have been performed to show that these boundaries can be seen in high resolution lattice images and the observed contrast is attributed to the presence of wrong Ga-Ga and P-P bonds at the inversion boundary.

Characterization of GaN grown on sapphire by laser-induced molecular beam epitaxy

2001 ◽  
Vol 16 (1) ◽  
pp. 261-267 ◽  
Author(s):  
H. Zhou ◽  
A. Rühm ◽  
N. Y. Jin-Phillipp ◽  
F. Phillipp ◽  
M. Gross ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
X Ray Diffraction ◽  
Fringe Contrast ◽  
Inversion Domain ◽  
Transmission Electron ◽  
Contrast Analysis ◽  
Inversion Domain Boundaries

GaN grown on sapphire (α–Al2O3) was characterized by laser-induced molecular beam epitaxy. Threading dislocations with Burgers vectors of 1/3〈1120〉, 1/3〈1123〉 and [0001] were observed with a predominance of the first type. Additionally, inversion domains with Ga-polarity existed with respect to the adjacent matrix, which was of N-polarity. The dislocation densities and coherence lengths were deduced from x-ray diffraction and found to be in accordance with those measured by transmission electron microscopy. Both displacement fringe contrast analysis and high-resolution transmission electron microscopy results indicated that the inversion domain boundaries had Ga–N bonds between domains and the adjacent matrix.

Enhanced Light Emission at Self-assembled GaN Inversion Domain Boundary

2011 ◽  
Vol 1324 ◽  
Author(s):  
Mei-Chun Liu ◽  
Yuh-Jen Cheng ◽  
Jet-Rung Chang ◽  
Chun-Yen Chang
Keyword(s):  
Molecular Beam ◽  
Light Emission ◽  
Domain Boundary ◽  
Mbe Growth ◽  
Polarity Inversion ◽  
Circular Pattern ◽  
Inversion Domain ◽  
Domain Boundaries ◽  
Self Assembled ◽  
Inversion Domain Boundaries

ABSTRACTWe report the fabrication of GaN lateral polarity inversion heterostructure with self assembled crystalline inversion domain boundaries (IDBs). The sample was fabricated by two step molecular-beam epitaxy (MBE) with microlithography patterning in between to define IDBs. Despite the use of circular pattern, hexagonal crystalline IDBs were self assembled from the circular pattern during the second MBE growth. Both cathodoluminescent (CL) and photoluminescent (PL) measurements show a significant enhanced emission at IDBs and in particular at hexagonal corners. The ability to fabricate self assembled crystalline IDBs and its enhanced emission property can be useful in optoelectronic applications.

Effects of defects on the morphologies of GaN nanorods grown on Si (111) substrates

2009 ◽  
Vol 24 (10) ◽  
pp. 3032-3037 ◽  
Author(s):  
Kyu Hyung Lee ◽  
Jeong Yong Lee ◽  
Y.H. Kwon ◽  
Tae Won Kang ◽  
J.H. You ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Polar Region ◽  
Domain Boundary ◽  
Hydride Vapor Phase Epitaxy ◽  
Slow Growth Rate ◽  
Selected Area Electron Diffraction ◽  
Inversion Domain ◽  
Transmission Electron ◽  
The One ◽  
Inversion Domain Boundaries

Scanning electron microscopy and transmission electron microscopy images and selected area electron diffraction pattern showed that the one-dimensional GaN nanorods with [0001]-oriented single-crystalline wurzite structures were formed on Si (111) substrates by using hydride vapor-phase epitaxy without a catalyst. Although some stacking faults and inversion domain boundaries existed in the GaN nanorods, few other defects such as threading dislocations were observed. The formation of the facet plane in the N-polar region of the GaN nanorod containing an inversion domain boundary originated from the slow growth rate, followed by the lateral adatom diffusion from the Ga-polar region to reduce the length difference.

Planar and Curved Defects in Aluminum Nitride: Their Microstructure and Microchemistry

1989 ◽  
Vol 167 ◽  
Author(s):  
Alistair D. Westwood ◽  
Michael R. Notis
Keyword(s):  
Electron Microscopy ◽  
Aluminum Nitride ◽  
Analytical Electron Microscopy ◽  
Microchemical Analysis ◽  
Inversion Domain ◽  
Transmission Electron ◽  
Proposed Model ◽  
Domain Boundaries ◽  
Convergent Beam ◽  
Inversion Domain Boundaries

AbstractThe microstructure and microchemistry of planar and curved defects in Aluminum Nitride (AIN) has been investigated using Conventional Transmission Electron Microscopy (CTEM), Convergent Beam Electron Diffraction (CBED), and Analytical Electron Microscopy (AEM) techniques. Both defect morphologies were identified as Inversion Domain Boundaries (IDB). Microchemical analysis revealed oxygen segregation to the planar faults; when present on the curved defects, oxygen was at a lower concentration than in the planar defect case. Annealing experiments on defect containing AIN support our microchemical analysis of oxygen segregation. A proposed model for the formation of these two types of boundaries is presented.

Sreels Analysis of Oxygen-Rich Inversion Domain Boundaries in Aluminum Nitride

1994 ◽  
Vol 357 ◽  
Author(s):  
J. Bruley ◽  
A.D. Westwood ◽  
R. A. Youngman ◽  
J.-C. Zhao ◽  
M.R. Notis
Keyword(s):  
Aluminum Nitride ◽  
Structural Model ◽  
Domain Boundary ◽  
Edge Structure ◽  
Spatially Resolved ◽  
Inversion Domain ◽  
Domain Boundaries ◽  
Length Data ◽  
Inversion Domain Boundaries ◽  
Electron Energy Loss

AbstractSpatially resolved electron energy loss spectroscopy analysis has been conducted on planar inversion domain boundaries in aluminum nitride. The defects were found to contain 1.5 monolayers of oxygen, in agreement with the most recent structural model of Westwood. From variations in near-edge structure, the local atomic environments of both oxygen and aluminum are compared with α-A1203, γ-A1203 and γ-AION standards. Based upon this study the stnrcture of the inversion domain boundary is found to resemble that of the cubic γ-AION spinel, and eliminates from consideration those structural models based upon ai-Al203. Furthermore, quantification of the shape resonances provided Al-O bond-length data from the inversion domain boundary interface. These distances closely agree with the Youngman Model that has recently been further refined by Westwood et al.

A TEM Study of Inversion Domain Boundaries Annihilation Mechanism in 3C-SiC during Growth

2009 ◽  
Vol 615-617 ◽  
pp. 331-334 ◽  
Author(s):  
Alkyoni Mantzari ◽  
Christos B. Lioutas ◽  
Efstathios K. Polychroniadis
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Physical Mechanism ◽  
Simulation Analysis ◽  
Inversion Domain ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Crystallographic Planes ◽  
Inversion Domain Boundaries

The aim of the present work is to study the evolution and the annihilation of inversion domain boundaries in 3C-SiC during growth. For this investigation conventional and high resolution transmission electron microscopy were employed. It is shown that the physical mechanism which results in the annihilation of inversion domain boundaries in 3C-SiC starting from the 3C-SiC/Si interface is the change of the crystallographic planes in which inversion domain boundaries propagate into the {111} ones. In all cases modeling and simulation analysis by EMS software [1] are in agreement with the experimental results.

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