Phase-selective Route to V-O Film Formation: A Systematic MOCVD Study Into the Effects of Deposition Temperature on Structure and Morphology

2015 ◽  
Vol 21 (10-11-12) ◽  
pp. 319-326 ◽  
Author(s):  
Simon F. Spanò ◽  
Roberta G. Toro ◽  
Guglielmo G. Condorelli ◽  
Grazia M. L. Messina ◽  
Giovanni Marletta ◽  
...  
Keyword(s):  
Deposition Temperature ◽  
Film Formation ◽  
Structure And Morphology

Surface Structure and Morphology of SrBi2Ta2O9 (SBT) Thin Films

1996 ◽  
Vol 440 ◽  
Author(s):  
Tingkai Li ◽  
Pete Zawadzki ◽  
Richard A. Stall ◽  
Chien-Hsiung Peng ◽  
Yongfei Zhu ◽  
...  
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Surface Structure ◽  
Grain Growth ◽  
Phase Formation ◽  
Deposition Temperature ◽  
Electric Properties ◽  
Step Process ◽  
Structure And Morphology ◽  
Structure Morphology

AbstractSrBi2Ta2O9 (SBT) films have been prepared by MOCVD processes. The phase formation, surface structure, morphology and surface roughness of SBT films on Pt/Ti/SiO2/Si wafers were measured by XRD, SEM, AFM and ellipsometry. It was found that amorphous SBT formed below 500°C, amorphous and polycrystalline growth occurred successively between 500°C and 650°C. The surface roughness of the SBT thin films also increased with increasing deposition temperature. The AFM results showed the nucleation of SBT started by island formation, then continued across the surface of substrates at lower deposition temperatures. When the SBT film was deposited at higher temperatures, the nucleation and grain growth occurred at the same time, resulting in an inhomogencous structure and much higher surface roughness. Therefore, a two step process is used to improve surface roughness and interface mismatch between film and substrate. In addition, the relationships between surface structure, morphology and the electric properties of SBT thin films were also investigated.

scholarly journals Influence of Temperature Reaction for the CdSe–TiO2 Nanotube Thin Film Formation via Chemical Bath Deposition in Improving the Photoelectrochemical Activity

Materials ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2533
Author(s):  
Chin Wei Lai ◽  
Nurul Asma Samsudin ◽  
Foo Wah Low ◽  
Nur Azimah Abd Samad ◽  
Kung Shiuh Lau ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Chemical Bath Deposition ◽  
Deposition Temperature ◽  
Film Formation ◽  
Photocurrent Density ◽  
Tio2 Nanotube ◽  
Cubic Phase ◽  
Photoelectrochemical Performance ◽  
Photoelectrochemical Activity

In this present work, we report the deposition of cadmium selenide (CdSe) particles on titanium dioxide (TiO2) nanotube thin films, using the chemical bath deposition (CBD) method at low deposition temperatures ranging from 20 to 60 °C. The deposition temperature had an influence on the overall CdSe–TiO2 nanotube thin film morphologies, chemical composition, phase transition, and optical properties, which, in turn, influenced the photoelectrochemical performance of the samples that were investigated. All samples showed the presence of CdSe particles in the TiO2 nanotube thin film lattice structures with the cubic phase CdSe compound. The amount of CdSe loading on the TiO2 nanotube thin films were increased and tended to form agglomerates as a function of deposition temperature. Interestingly, a significant enhancement in photocurrent density was observed for the CdSe–TiO2 nanotube thin films deposited at 20 °C with a photocurrent density of 1.70 mA cm−2, which was 17% higher than the bare TiO2 nanotube thin films. This sample showed a clear surface morphology without any clogged nanotubes, leading to better ion diffusion, and, thus, an enhanced photocurrent density. Despite having the least CdSe loading on the TiO2 nanotube thin films, the CdSe–TiO2 nanotube thin films deposited at 20 °C showed the highest photocurrent density, which confirmed that a small amount of CdSe is enough to enhance the photoelectrochemical performance of the sample.

scholarly journals Film formation of non-planar phthalocyanines on copper(i) iodide

RSC Advances ◽  
2016 ◽  
Vol 6 (97) ◽  
pp. 95227-95231 ◽  
Author(s):  
A. J. Ramadan ◽  
S. Fearn ◽  
T. S. Jones ◽  
S. Heutz ◽  
L. A. Rochford
Keyword(s):  
Film Formation ◽  
High Substrate Temperature ◽  
Ion Scattering ◽  
X Ray Diffraction ◽  
Temperature Growth ◽  
X Ray ◽  
Force Microscopy ◽  
Structure And Morphology ◽  
Atomic Force ◽  
Low Energy Ion Scattering

Structural templating and high substrate temperature growth are combined to study the differences in structure and morphology of two non-planar phthalocyanines using X-ray diffraction, atomic force microscopy and low energy ion scattering.

Structures and crystallization of vacuum-deposited amorphous Se and Sb films

1990 ◽  
Vol 48 (4) ◽  
pp. 140-141
Author(s):  
Makoto Shiojiri ◽  
Toshiyuki Isshiki ◽  
Tetsuya Fudaba ◽  
Yoshihiro Hirota
Keyword(s):  
Monte Carlo ◽  
Electron Microscope ◽  
Monte Carlo Method ◽  
Computer Program ◽  
Radial Distribution ◽  
Film Formation ◽  
Amorphous State ◽  
Two Dimensional ◽  
Amorphous Films ◽  
Binding Condition

In hexagonal Se crystal each atom is covalently bound to two others to form an endless spiral chain, and in Sb crystal each atom to three others to form an extended puckered sheet. Such chains and sheets may be regarded as one- and two- dimensional molecules, respectively. In this paper we investigate the structures in amorphous state of these elements and the crystallization.HRTEM and ED images of vacuum-deposited amorphous Se and Sb films were taken with a JEM-200CX electron microscope (Cs=1.2 mm). The structure models of amorphous films were constructed on a computer by Monte Carlo method. Generated atoms were subsequently deposited on a space of 2 nm×2 nm as they fulfiled the binding condition, to form a film 5 nm thick (Fig. 1a-1c). An improvement on a previous computer program has been made as to realize the actual film formation. Radial distribution fuction (RDF) curves, ED intensities and HRTEM images for the constructed structure models were calculated, and compared with the observed ones.

Lipid Polymorphism and Virus-Membrane Fusion as Observed in Vitrified Thin Films by Cryo-Electron Microscopy

1990 ◽  
Vol 48 (1) ◽  
pp. 492-493
Author(s):  
P.M. Frederik ◽  
K.N.J. Burger ◽  
M.C.A. Stuart ◽  
A.J. Verkleij
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Membrane Fusion ◽  
Film Formation ◽  
Molar Ratio ◽  
Influenza B ◽  
Complex Structures ◽  
Type Ii ◽  
Suspended Material ◽  
Cryo Electron Microscopy

Cellular membranes are often composed of phospholipid mixtures in which one or more components have a tendency to adopt a type II non-bilayer lipid structure such as the inverted hexagonal (H||) phase. The formation of a type II non-bilayer intermediate, the inverted lipid micel is proposed as the initial step in membrane fusion (Verkleij 1984, Siegel, 1986). In the various forms of cellular transport mediated by carrier vesicles (e.g. exocytosis, endocytosis) the regulation of membrane fusion, and hence of inverted lipid micel formation, is of vital importance.We studied the phase behaviour of simple and complex lipid mixtures by cryo-electron microscopy to gain more insight in the ultrastructure of different lipid phases (e.g. Pβ’, Lα, H||) and in the complex membrane structures arising after Lα < - > H|| phase changes (e.g. isotropic, cubic). To prepare hydrated thin films a 700 mesh hexagonal grid (without supporting film) was dipped into and withdrawn from a liposome suspension. The excess fluid was blotted against filter paper and the thin films that form between the bars of the specimen grid were immediately (within 1 second) vitrified by plunging of the carrier grids into ethane cooled to its melting point by liquid nitrogen (Dubochet et al., 1982). Surface active molecules such as phospholipids play an important role in the formation and thinning of these aqueous thin films (Frederik et al., 1989). The formation of two interfacial layers at the air-water interfaces requires transport of surface molecules from the suspension as well as the orientation of these molecules at the interfaces. During the spontaneous thinning of the film the interfaces approach each other, initially driven by capillary forces later by Van der Waals attraction. The process of thinning results in the sorting by size of the suspended material and is also accompanied by a loss of water from the thinner parts of the film. This loss of water may result in the concentration and eventually in partial dehydration of suspended material even if thin films are vitrified within 1 sec after their formation. Film formation and vitrification were initiated at temperatures between 20-60°C by placing die equipment in an incubator provided widi port holes for the necessary manipulations. Unilamellar vesicles were made from dipalmitoyl phosphatidyl choline (DPPC) by an extrusion method and showed a smooth (Lα) or a rippled (PB’.) structure depending on the temperature of the suspensions and the temperature of film formation (50°C resp. 39°C) prior to vitrification. The thermotropic phases of hydrated phospholipids are thus faithfully preserved in vitrified thin films (fig. a,b). Complex structures arose when mixtures of dioleoylphosphatidylethanol-amine (DOPE), dioleoylphosphatidylcholine (DOPC) and cholesterol (molar ratio 3/1/2) are heated and used for thin film formation. The tendency of DOPE to adopt the H|| phase is responsible for the formation of complex structures in this lipid mixture. Isotropic and cubic areas (fig. c,d) having a bilayer structure are found in coexistence with H|| cylinders (fig. e). The formation of interlamellar attachments (ILA’s) as observed in isotropic and cubic structures is also thought to be of importance in biological fusion events. Therefore the study of the fusion activity of influenza B virus with liposomes (DOPE/DOPC/cholesterol/ganglioside in a molar ratio 1/1/2/0.2) was initiated. At neutral pH only adsorption of virus to liposomes was observed whereas 2 minutes after a drop in pH (7.4 - > 5.4) fusion between virus and liposome membranes was demonstrated (fig. f). The micrographs illustrate the exciting potential of cryo-electron microscopy to study lipid-lipid and lipid-protein interactions in hydrated specimens.

EFFECT OF DEPOSITION TEMPERATURE ON PLASMA GROWN ALUMINUM OXIDE FILMS

1988 ◽  
Vol 49 (C4) ◽  
pp. C4-409-C4-412 ◽  
Author(s):  
C. BOURREAU ◽  
Y. CATHERINE
Keyword(s):  
Aluminum Oxide ◽  
Deposition Temperature ◽  
Oxide Films
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