Ferroelectric Domain Boundaries Induced by Interface Mismatch Dislocations in BaTiO3/LaAlO3

1996 ◽  
Vol 466 ◽  
Author(s):  
Z. L. Wang ◽  
Z. R. Dai
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Ferroelectric Domain ◽  
Organic Chemical ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Metal Organic ◽  
Organic Chemical Vapor Deposition

ABSTRACTInterface microstractures of BaTiO3/LaAlO3 grown by metal-organic chemical vapor deposition (MOCVD) are studied using high-resolution transmission electron microscopy (HRTEM). Interface dislocations in BaTiO3/LaAlO3 have been shown to be directly linked with the 90° domain boundaries in BaTiO3. This association is a result of strain relief due to a phase transformation on cooling from the growth temperature. The {100} surfaces of BaTiO3 are terminated with the Ba-O layer.

TEM Study of MOCVD Grown InSb/GaAs Heterostructures with and without TMIn Predeposited Layers

1994 ◽  
Vol 340 ◽  
Author(s):  
L. H. Kuo ◽  
Susan Z. Hua ◽  
L. Salamanca-Riba ◽  
D. L. Partin ◽  
L. Green ◽  
...  
Keyword(s):  
Vapor Deposition ◽  
Chemical Vapor ◽  
Organic Chemical ◽  
Threading Dislocations ◽  
High Quality ◽  
Gaas Substrates ◽  
Transmission Electron ◽  
Metal Organic ◽  
Step Growth ◽  
Organic Chemical Vapor Deposition

ABSTRACTHigh quality InSb epilayers were grown on GaAs substrates by metal organic chemical vapor deposition using a two-step growth procedure involving trimethal indium (TMIn) predeposition. From transmission electron microscopy studies, we found that an interdiffusion layer of thickness of 10 Å forms at the interface when the substrate is exposed to TMIn for approximately 6 secs prior to the growth of the InSb filns. Hall mobilities up to σ 52,000 cm2/V-s were obtained at 300 K on a 2.1-μm-thick InSb heteroepitaxial film. In contrast, samples without TMIn predeposition showed polycrystallinity of the InSb films grown on single crystalline GaAs substrates. The effect. of TMNIn predeposition is to minimize the misorientation of the grains, suppress the polycrystallinity, decrease the density of threading dislocations, and increase the electron mobilities in the films. However, we found that too much TMIn predeposition gives rise t.o an intermixing layer at the InSb/GaAs interface which deteriorates the film quality. Details of the effect of the TMIn predeposition on the microstructure of InSb/GaAs with different predeposition times (zero, 6, and 12 secs) are discussed.

Pinning of 90° domain boundaries at interface dislocations in BaTiO3/LaAIO3 {100}

1996 ◽  
Vol 54 ◽  
pp. 124-125
Author(s):  
Z.-R. Dai ◽  
Z.L. Wang ◽  
X.F. Duan ◽  
J. Zhang
Keyword(s):  
Thin Films ◽  
Chemical Vapor ◽  
Organic Chemical ◽  
Epitaxial Thin Films ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Potential Applications ◽  
Metal Organic ◽  
Organic Chemical Vapor Deposition

Epitaxially grown BaTiO3 thin films have potential applications in microelectronics and integrated photonics. The ferroelectric property of this material is largely determined by the domain structure. It is believed that the structure of the substrate would have profound effect on the quality of BaTiO3 epitaxial thin films. This paper reports our studies on the pinning of 90° domain boundaries at interface dislocations.Epitaxial BaTiO3 thin films were deposited on single crystalline LaAIO3 (100) substrates at 800°C by metal-organic chemical vapor deposition (MOCVD). Cross-section specimens of the films were studied at 200 kV using an JEOL 2010 high-resolution transmission electron microscope (HRTEM).

Controlled growth and characterization of monolayer MoS2 by using metal-organic chemical vapor deposition

2021 ◽  
Vol 66 (1) ◽  
pp. 49-56
Author(s):  
Quyen Do Le ◽  
Duc Nguyen Anh
Keyword(s):  
Electron Microscopy ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Transition Metal Dichalcogenides ◽  
Chemical Vapor ◽  
Inorganic Materials ◽  
Organic Chemical ◽  
Sio2 Substrate ◽  
Metal Organic ◽  
Organic Chemical Vapor Deposition

Recently, novel physical properties originating from quantum confinement endow the twodimensional (2D) transition metal dichalcogenides, such as MoS2, or WSe2 to attract a great deal of attention. However, the synthesis of 2D-TMDC has to be still limited, in which the precursors are almost based on high vapor pressure inorganic materials, that produce a smallscale film, and it is mainly performed only on conventional Si\SiO2 substrate. In this work, we successfully synthesize the atomic thickness of 2D-MoS2 films by using metal-organic chemical vapor deposition (MOCVD) on several kinds of substrate, namely silicon (Si), silicon dioxide (SiO2), graphite foil, or fluorine-doped tin oxide (FTO). The morphology of samples is observed by field emission scanning electron microscopy (FE-SEM), and scanning transmission electron microscopy (STEM). The lattice vibrational and optical properties are investigated by Raman and photoluminescence (PL) spectroscopies, respectively. With the same MOCVD growing condition, as-obtained samples exhibit the hexagonal configuration (2H phase), whereas the surface morphology and the thickness show a discrepancy, depending on the substrates.

scholarly journals Phase Change Ge-Rich Ge–Sb–Te/Sb2Te3 Core-Shell Nanowires by Metal Organic Chemical Vapor Deposition

Nanomaterials ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3358
Author(s):  
Arun Kumar ◽  
Raimondo Cecchini ◽  
Claudia Wiemer ◽  
Valentina Mussi ◽  
Sara De Simone ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Organic Chemical ◽  
Core Shell ◽  
The Core ◽  
Metal Organic ◽  
Organic Chemical Vapor Deposition ◽  
Shell Nanowires

Ge-rich Ge–Sb–Te compounds are attractive materials for future phase change memories due to their greater crystallization temperature as it provides a wide range of applications. Herein, we report the self-assembled Ge-rich Ge–Sb–Te/Sb2Te3 core-shell nanowires grown by metal-organic chemical vapor deposition. The core Ge-rich Ge–Sb–Te nanowires were self-assembled through the vapor–liquid–solid mechanism, catalyzed by Au nanoparticles on Si (100) and SiO2/Si substrates; conformal overgrowth of the Sb2Te3 shell was subsequently performed at room temperature to realize the core-shell heterostructures. Both Ge-rich Ge–Sb–Te core and Ge-rich Ge–Sb–Te/Sb2Te3 core-shell nanowires were extensively characterized by means of scanning electron microscopy, high resolution transmission electron microscopy, X-ray diffraction, Raman microspectroscopy, and electron energy loss spectroscopy to analyze the surface morphology, crystalline structure, vibrational properties, and elemental composition.

A Drastic Change in Structure and Property of TiO2 Thin Films Deposited by Metal-Organic Chemical Vapor Deposition With Deposition Temperature

2000 ◽  
Vol 616 ◽  
Author(s):  
Jeong-Hoon Park ◽  
Woon-Jo Cho ◽  
Kug-Sun Hong
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Refractive Index ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Deposition Temperature ◽  
Chemical Vapor ◽  
Organic Chemical ◽  
Metal Organic ◽  
Organic Chemical Vapor Deposition

AbstractTiO2 thin films were deposited by metal-organic chemical vapor deposition (MOCVD) method using titanium tetraisopropoxide(TTIP). A drastic change in structural aspect and its property occurred when the deposition temperature increased above 400°C. Deposition kinetics was proved to transit from reaction controlled regime into diffusion controlled regime above about 400°C in Arrehnius plot. In X-ray diffraction (XRD)and infrared reflectance spectra, it was observed that the crystallinity was decreased significantly around 400°C. The surface microstructure has changed explicitly from dense structure with larger grains to porous one with smaller grains observed by scanning electron microscopy and transmission electron microscopy. Electrical resistance of the films jumped by 2 orders of magnitude, which is measured by the 4-point probe method. The refractive index calculated by Swanepoel's method has decreased from 2.45 to 2.28 at 630nm. The porous microstructure of films deposited at above 400°C was thought to be responsible for the significant decrease in electrical conductivity and refractive index of the films.

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