Multilayered Structures of SrNb0.1Ti0.9O3/La0.8Sr0.2MnO3/SrTiO3 Prepared by Laser Molecular Beam Epitaxy

2002 ◽  
Vol 17 (3) ◽  
pp. 600-608
Author(s):  
X. L. Ma ◽  
H. B. Lu ◽  
F. Chen ◽  
Z. H. Chen ◽  
G. Z. Yang
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Theoretical Calculations ◽  
Geometrical Model ◽  
Charge Ordering ◽  
Multilayered Structures ◽  
Laser Molecular Beam Epitaxy ◽  
Transmission Electron ◽  
Orthorhombic Cell ◽  
Resolution Imaging

Multilayer oxides of SrNb0.1Ti0.9O3/La0.8Sr0.2MnO3/SrTiO3 have been grown by computer-controlled laser molecular beam epitaxy and characterized by transmission electron microscopy. Electron microdiffractions and high-resolution imaging reveal that the as-prepared thin film of La0.8Sr0.2MnO3 with thickness of 200 nm is epitaxially grown on the SrTiO3(001) substrate and the SrNb0.1Ti0.9O3 with thickness of 250 nm epitaxially on the as-received La0.8Sr0.2MnO3 film. The microstructures in the La0.8Sr0.2MnO3 film are clarified in terms of the oriented microdomains. In contrast, microstructures in SNTO are featured by the formation of superstructures due to charge ordering. Crystallographic relationships of these domains are discussed on the basis of an orthorhombic cell and rationalized by theoretical calculations based on a geometrical model.

Study on Barium Strontium Titanate Thin Films Integrated on Si Substrates by Laser Molecular Beam Epitaxy

2009 ◽  
Vol 79-82 ◽  
pp. 823-826
Author(s):  
X.Y. Zhou ◽  
Yun Zhou ◽  
G.Y. Wang ◽  
Y. Wang ◽  
Helen Lai Wah Chan ◽  
...  
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Lattice Structure ◽  
Bias Field ◽  
Sio2 Layer ◽  
X Ray Diffraction ◽  
Cross Sectional ◽  
Laser Molecular Beam Epitaxy ◽  
Si Substrates ◽  
Transmission Electron

(Ba,Sr)TiO3 thin film has been deposited on Si (001) wafer with the SiO2 layer as the block layer through laser molecular-beam epitaxy using an ultra thin Sr layer as template. X-ray diffraction measurements and the cross-sectional observations under transmission electron microscope indicated that BST was well crystallized. This deposition of Sr layer is considered to remove the thin SiO2 layer to produce a layer, which is crystallized and has a lattice structure matching with that of perovskite BST. The maximum in-plane dielectric tunability is calculated to be 50% at 1 GHz under a moderate DC bias field of 13.3 V/µm. This BST/Si structure is believed to be a promising candidate in the development of ferroelectric BST-based microwave devices.

High-Resolution Imaging of Coga/GaAs and Eras/GaAs Interfaces

1989 ◽  
Vol 159 ◽  
Author(s):  
Jane G. Zhu ◽  
Stuart McKeman ◽  
Chris J. Palmstrøm ◽  
C. Barry Carter
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Atomic Scale ◽  
High Resolution Imaging ◽  
Transmission Electron ◽  
Resolution Imaging ◽  
Interface Structures

ABSTRACTCoGa/GaAs and ErAs/GaAs grown by molecular-beam epitaxy have been studied using high-resolution transmission electron microscopy (HRTEM). The epitactic interfaces have been shown to be abrupt on the atomic scale. Computer simulations of the HRTEM images have been obtained for different interface structures under various specimen and image conditions. Practical problems in the comparison between the simulated and experimental images are discussed.

Interface Characterization of AlN/TiN/MgO(001) Prepared by Molecular Beam Epitaxy

1999 ◽  
Vol 14 (4) ◽  
pp. 1597-1603 ◽  
Author(s):  
X. L. Ma ◽  
N. Shibata ◽  
Y. Ikuhara
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Theoretical Calculations ◽  
Substrate Surface ◽  
High Resolution Electron Microscopy ◽  
Structure Type ◽  
Geometrical Model ◽  
Cross Sectional ◽  
Resolution Electron ◽  
Relationship Of

The AlN/TiN/MgO(001) interfaces, prepared by molecular beam epitaxy, have been characterized by cross-sectional high-resolution electron microscopy (HREM). The thin TiN buffer layer, with the thickness of 40 nm, is epitaxially grown on the MgO(001) substrate. Owing to the same structure-type as well as the small mismatch of their lattice parameters, the growth is governed by the parallel orientation relationship of (001)TiN||(001)MgO, (010)TiN||(010)MgO, and (111)TiN||(111)MgO. Two kinds of processes of the hexagonal AlN epitaxial growth on the as-received TiN(001), differed by the (0001)AlN plane parallel to, and the (1012) plane approximately parallel to the MgO substrate surface, respectively, are identified, and within them, several cases are classified which are based on the consideration of crystallographic symmetry. Theoretical calculations based on the geometrical model that was recently proposed and applied to a number of epitaxial systems have been carried out to rationalize these observations.

Structural and Optical Properties of InAsSbBi Grown by Molecular Beam Epitaxy on Offcut GaSb Substrates

Photonics ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 215
Author(s):  
Rajeev R. Kosireddy ◽  
Stephen T. Schaefer ◽  
Marko S. Milosavljevic ◽  
Shane R. Johnson
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Optical Quality ◽  
X Ray Diffraction ◽  
Interface Quality ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Lateral Variations

Three InAsSbBi samples are grown by molecular beam epitaxy at 400 °C on GaSb substrates with three different offcuts: (100) on-axis, (100) offcut 1° toward [011], and (100) offcut 4° toward [011]. The samples are investigated using X-ray diffraction, Nomarski optical microscopy, atomic force microscopy, transmission electron microscopy, and photoluminescence spectroscopy. The InAsSbBi layers are 210 nm thick, coherently strained, and show no observable defects. The substrate offcut is not observed to influence the structural and interface quality of the samples. Each sample exhibits small lateral variations in the Bi mole fraction, with the largest variation observed in the on-axis growth. Bismuth rich surface droplet features are observed on all samples. The surface droplets are isotropic on the on-axis sample and elongated along the [011¯] step edges on the 1° and 4° offcut samples. No significant change in optical quality with offcut angle is observed.

Vertical self-organization of Ge1−xMnx nanocolumn multilayers grown on Ge(001) substrates

2016 ◽  
Vol 30 (20) ◽  
pp. 1650269 ◽  
Author(s):  
Thi Giang Le ◽  
Minh Tuan Dau
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Molecular Beam Epitaxy ◽  
Elastic Constant ◽  
Structural Properties ◽  
Molecular Beam ◽  
Self Organization ◽  
Transmission Electron ◽  
2D Model

High-resolution transmission electron microscopy (HR-TEM) has been used to investigate the structural properties of GeMn/Ge nanocolumns multilayer samples grown on Ge(001) substrates by means of molecular beam epitaxy (MBE) system. Four bilayers with the spacer thickness in the range between 6 nm and 15 nm and 10 periods of bilayers of Ge[Formula: see text]Mn[Formula: see text]/Ge nanocolumn are presented. A simplified 2D model based on the theory of elastic constant interactions has been used to provide reasonable explanations to the vertical self-organization of GeMn nanocolumns in multilayers.

Asymmetric Cracking in Znse/ZnSxSel−x Superlattices Grown by Molecular Bean Epitaxy

1987 ◽  
Vol 102 ◽  
Author(s):  
Richard J. Dalby ◽  
John Petruzzello
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Thermal Expansion ◽  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Lattice Mismatch ◽  
Sulfur Concentration ◽  
Transmission Electron ◽  
Theoretical Predictions ◽  
Superlattice Layer

ABSTRACTOptical and transmission electron microscopy have been used to study cracks appearing in ZnSe/ZnSxSe1−x (x ∼ 0.38) superlattices grown by Molecular Beam Epitaxy. It Is shown that when a fracture occurs it is confined, in most cases, to the superlattice and propagates along <011> cleavage directions in these <001> oriented epilayers. Cracks were not observed in all superlattices and their onset is discussed in relation to sulfur concentration, overall superlattice height, individual superlattice layer thicknesses, and stress, tensile or compressive, due to lattice mismatch and thermal expansion differences between buffer layer and superlattice. It was found that by adjusting the controllable parameters, cracks in the superlattices could be eliminated. Orientation and density of these features have been related to asynnmetric cracking associated with the zincblende structure of these II-VI materials. Experimental results are shown to be in agreement with theoretical predictions of critical heights for the onset of cracking.

Sign in / Sign up

Export Citation Format

Share Document