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Article
TEM Study of High Quality GaN Grown by OMVPE Using an Intermediate Layer
We report on high quality GaN layers grown with the use of one intermediate layer. The defect analysis shows that the density of dislocation is only 8×107/cm2 in these layers, compared to over 1010/cm2 for layers...
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Article
Atomic Structure of the Interfaces Between Silicon Directly Bonded Wafers
The so-called Direct Wafer Bonding (DWB) technique opens new possibilities for the electronic industry but still suffers from the poor knowledge we have of the microstructure of these interfaces and hence of t...
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Article
Direct Wafer Bonding of Preamorphized Silicon Wafers.
This paper presents the comparison of the structural and electrical characteristics of Si/Si bonded interfaces depending on whether the surface layers were rendered amorphous by high dose ion implantation prio...
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Article
Polarity of GaN
Convergent beam electron diffraction (CBED) was applied to study polarity of GaN heterolayers grown by MOCVD on sapphire and SiC substrates and also mechano-chemically polished bulk GaN platelet crystals grown...
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Article
TEM Study of Defects in Laterally Overgrown GaN Layers
Transmission electron microscopy was applied to study defects in laterally overgrown GaN layers, with initial growth on Al2O3 substrates followed by further growth over SiO2 masks. Dislocations found in the overg...
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Article
The Role of the Multi Buffer Layer Technique on the Structural Quality of GaN
Successive growth of thick GaN layers separated by either LT-GaN or LT-AlN interlayers have been investigated by transmission electron microscopy techniques. One of the objectives of this growth method was to ...
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Article
Mg Segregation, Difficulties of P-Do** in GaN
Transmission electron microscopy has been used to study defects formed in Mg-doped GaN crystals. Three types of crystals have been studied: bulk crystals grown by a high pressure and high temperature process w...
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Article
Effect of the Do** and the Al Content on the Microstructure and Morphology of Thin AlxGa1−xN Layers Grown by MOCVD
AlxGa1−xN {x=30% (doped and undoped), 45% (doped)} thin films were grown by MOCVD on ∼2 μm thick GaN layer using Al2O3 substrate. These films were designed to be the active parts of HFETs with nsμ product of abou...
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Article
Relaxation of InGaN thin layers observed by X-ray and transmission electron microscopy studies
Double-crystal and triple-axis x-ray diffractometry and transmission electron microscopy are used to characterize the microstructure, strain, and composition of InGaN layers grown on GaN by metalorganic chemic...
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Article
Mechanisms of dislocation reduction in GaN using an intermediate temperature interlayer
A dramatic reduction of the dislocation density in GaN was obtained by insertion of a single thin interlayer grown at an intermediate temperature (IT-IL) after the initial growth at high temperature. A descrip...
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Article
Atomic Scale Analysis of InGaN Multi-Quantum Wells
InGaN multiquantum wells grown by MOCVD on GaN have been investigated by transmission electron microscopy techniques and numerical analysis of high resolution (HREM) images. One objective of this research was ...
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Article
TEM Study of Mg-Doped Bulk GaN Crystals
Transmission electron microscopy was applied to cross-sectioned samples to study surface morphology, sample polarity and defect distribution in bulk GaN samples doped with Mg. These crystals were grown from a ...
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Article
Tem Study of Defects in Laterally Overgrown GaN Layers
Transmission electron microscopy was applied to study defects in laterally overgrown GaN layers, with initial growth on A12O3 substrates followed by further growth over SiO2 masks. Dislocations found in the overg...
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Article
The Role of the Multi Buffer Layer Technique on the Structural Quality of GaN
Successive growth of thick GaN layers separated by either LT-GaN or LT-AlN interlayers have been investigated by transmission electron microscopy techniques. One of the objectives of this growth method was to ...
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Article
Mg Segregation, Difficulties of P-Do** in GaN
Transmission electron microscopy has been used to study defects formed in Mg-doped GaN crystals. Three types of crystals have been studied: bulk crystals grown by a high pressure and high temperature process w...
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Article
Effect of the Do** and the Al Content on the Microstructure and Morphology of Thin AlxGa1t-xN Layers Grown by MOCVD
AlxGa1−xN {x=30% (doped and undoped), 45% (doped)} thin films were grown by MOCVD on ∼2 µm thick GaN layer using Al2O3 substrate. These films were designed to be the active parts of HFETs with nsí product of abou...
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Article
Structural and Magnetic Properties of Well-Ordered Inverted Core-Shell α-Cr2O3/ α-MxCr2-xO3 (M=Co, Ni, Mn, Fe) Nanoparticles
Magnetic core shell nanoparticles (NPs) have potential for applications in magnetic random access memory, spintronic devices, and drug delivery systems. Our investigations are focused on the synthesis of inver...
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Article
Formaldehyde sensing characteristics of calcium-doped zinc oxide nanoparticles-based gas sensor
Ca-doped ZnO (CZO) nanopowders were synthesized via a simple sol–gel method. The effects of calcium on the structural, morphological, and optical properties of the resultant powders were investigated. The XRD ...
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Article
High response to sub-ppm level of NO2 with 50%RH of ZnO sensor obtained by an auto-combustion method
Pure zinc oxide was prepared by a simple auto-combustion method. The microstructure and morphological proprieties, of the prepared sample, were investigated by XRD, XPS, and SEM characterizations which indicat...
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Article
Study of ZnO room temperature NO2 sensor under illumination prepared by auto-combustion
ZnO nanoparticles have been prepared by auto-combustion method. Morphological and structural properties of the prepared samples were investigated by SEM, XRD, Raman and XPS characterizations. The XRD diffracto...
