Growth mechanism of YBa2Cu3O7–δthin films and precipitates on planar and vicinal SrTiO3substrates

2000 ◽  
Vol 15 (3) ◽  
pp. 596-613 ◽  
Author(s):  
J. Kim ◽  
D. B. Chrisey ◽  
J. S. Horwitz ◽  
M. M. Miller ◽  
C. M. Gilmore
Keyword(s):  
Critical Temperature ◽  
Electrical Properties ◽  
Film Thickness ◽  
Growth Mechanism ◽  
Growth Temperature ◽  
Flow Mode ◽  
Island Growth ◽  
Step Flow ◽  
Growth Modes ◽  
Initial Nucleation

Effects of the vicinal angle, film thickness, and temperature on the growth modes, microstructures, and electrical properties of YBa2Cu3O7–δon SrTiO3were studied. Island growth transition between the initial nucleation and the later coalescence stages was observed with film thickness on a planar SrTiO3, while no islands were observed at the later stage due to the step-flow mode. As the growth temperature increased,a-axis precipitates were transformed toc-axis precipitates (islands), while no islands formed on vicinal SrTiO3. The supercurrent critical temperature was strongly related to the substrate vicinal angle due to the step-flow mode.

Epitaxial YBa2Cu3O7−x Thin Films: Scanning Tunneling Microscope Study of the Initial Stages of Epitaxial Growth, Growth Mechanism, and Effects of Substrate Temperature

1991 ◽  
Vol 237 ◽  
Author(s):  
Shen Zhu ◽  
Douglas H. Lowndes ◽  
X.-Y. Zheng ◽  
David P. Norton ◽  
R. J. Warmack
Keyword(s):  
Film Thickness ◽  
Growth Mechanism ◽  
Growth Temperature ◽  
Lattice Mismatch ◽  
Unit Cell ◽  
Growth Mode ◽  
Spiral Growth ◽  
Scanning Tunneling ◽  
Growth Stages ◽  
Island Growth

ABSTRACTThe surface microstructure of epitaxial YBa2Cu3O7−x films grown by pulsed laser ablation on (001) MgO and SrTiO3 substrates has been studied at various growth stages, ranging in thickness from eight c-axis perpendicular unit cells to ∼220 nm. On MgO (lattice mismatch ∼9%) even the thinnest films grow unit cell-by-unit cell by an island growth mechanism. However, on SrTi03 (mismatch ∼1%), a transition from a layer-like growth mode to island growth is observed as the film thickness increases. Islands with clear spiral growth structures are observed in even the thinnest films on MgO, but for films grown on SrTiO3 the spiral growth features are found only for film thicknesses slightly greater than the critical thickness for the switch to an island growth mode. The islands consist of stacks of atomically flat terraces whose step heights are multiples of the c-axis lattice parameter. The island density decreases significantly with increasing film thickness, while their diameters range from 50–400 nm, increasing with growth temperature. The terraced island grain morphology causes a surface roughness of from 10 to 30 nm (depending on growth temperature) in films ∼200 nm thick.

AFM Observations on the Growth Mechanisms of Epitaxial Perovskite Oxide SrRuO3 Thin Films

1997 ◽  
Vol 474 ◽  
Author(s):  
R. A. Rao ◽  
Q. Gan ◽  
C. B. Eom
Keyword(s):  
Thin Films ◽  
Growth Mechanism ◽  
Three Dimensional ◽  
Plane Domain ◽  
Perovskite Oxide ◽  
X Ray Diffraction ◽  
Island Growth ◽  
Step Flow ◽  
Atomic Force ◽  
Step Flow Growth

ABSTRACTThe growth mechanism and surface morphology of epitaxial SrRuO3 thin films deposited on exact and vicinal (001) SrTiO3 and exact (001) LaAlO3 substrates has been studied. Vicinal substrates with miscut angle, a, up to 4° toward [010] direction were used. Atomic force microscope images show that the films grown on exact (001) SrTiO3 substrate had a growth mechanism involving two dimensional nucleation. In contrast, characteristic step patterns were observed on the films deposited on vicinal substrates, suggesting that these films had a step flow growth mode. The films deposited on exact (001) LaAlO3 substrates had a three dimensional island growth, due to the incoherence between the film and substrate lattice. These results were found to be consistent with the results of x-ray diffraction analysis of the in-plane domain structure.

Oblique-incidence Reflectivity Difference (OI-RD) and Leed Studies of Adsorption and Growth of Xe on Nb(110)

2003 ◽  
Vol 780 ◽  
Author(s):  
P. Thomas ◽  
E. Nabighian ◽  
M.C. Bartelt ◽  
C.Y. Fong ◽  
X.D. Zhu
Keyword(s):  
Transition Layer ◽  
Layer Growth ◽  
Flow Mode ◽  
Layer By Layer ◽  
Zeroth Order ◽  
Step Flow ◽  
Low Energy Electron Diffraction ◽  
Oriented Film ◽  
Low Energy Electron

AbstractWe studied adsorption, growth and desorption of Xe on Nb(110) using an in-situ obliqueincidence reflectivity difference (OI-RD) technique and low energy electron diffraction (LEED) from 32 K to 100 K. The results show that Xe grows a (111)-oriented film after a transition layer is formed on Nb(110). The transition layer consists of three layers. The first two layers are disordered with Xe-Xe separation significantly larger than the bulk value. The third monolayer forms a close packed (111) structure on top of the tensile-strained double layer and serves as a template for subsequent homoepitaxy. The adsorption of the first and the second layers are zeroth order with sticking coefficient close to one. Growth of the Xe(111) film on the transition layer proceeds in a step flow mode from 54K to 40K. At 40K, an incomplete layer-by-layer growth is observed while below 35K the growth proceeds in a multilayer mode.

Measurements of Film Thickness and Growth Temperature of YBa 2 Cu 3 O 7-δ Films by Pyrometric Absorption Method

1997 ◽  
Vol 14 (5) ◽  
pp. 367-370
Author(s):  
Xiong Xu-ming ◽  
Zhou Yue-liang ◽  
Wang Hui-sheng ◽  
Cui Da-fu ◽  
Lü Hui-bin ◽  
...  
Keyword(s):  
Film Thickness ◽  
Growth Temperature ◽  
Absorption Method

SHAPE EVOLUTION IN ONE-DIMENSIONAL ZnO NANOSTRUCTURES GROWN FROM ZnO NANOPOWDER SOURCE: VAPOR–LIQUID–SOLID VERSUS VAPOR–SOLID GROWTH MECHANISMS

2011 ◽  
Vol 10 (01n02) ◽  
pp. 75-79 ◽  
Author(s):  
SOUMEN DHARA ◽  
P. K. GIRI
Keyword(s):  
Growth Mechanism ◽  
Growth Temperature ◽  
Shape Evolution ◽  
Zno Nanostructures ◽  
Growth Mechanisms ◽  
Vapor Liquid Solid ◽  
One Dimensional ◽  
Zno Nanopowder ◽  
Simultaneous Growth ◽  
Vapor Liquid

Here we report on the growth and evolution of ZnO nanowires grown from ZnO nanopowder as a source material using a horizontal muffle furnace. The shape evolution has been studied with variation in growth temperature and zinc vapor pressure. The structural analysis on these nanostructures shows c-axis oriented aligned growth. Scanning electron microscopy imaging of these nanostructures revealed the shape evolution from nanowires to nanoribbons and then to nanorods as the growth temperature increases from 650°C to 870°C. At 650°C, only vertical nanowires have been observed and with increase in growth temperature nanowires transform to nanoribbons and then to nanorods at 870°C. And we also observed simultaneous growth of nanorods and nanoribbons under a specific growth condition. We believe that these nanowires and nanorods were formed by vapor–liquid–solid growth mechanism (catalyst-mediated growth), whereas nanoribbons were grown by vapor–solid growth mechanism (without the aid of a metal catalyst). We observed simultaneous occurrence of vapor–liquid–solid and vapor–solid growth mechanisms at a particular growth temperature. These ZnO nanowires exhibit bound exciton related UV emission at ~379 nm, and defect-emission band in the visible region. Possible growth mechanism, shape evolution, and simultaneous growth of two types of one-dimensional ZnO nanostructures under the same growth condition are discussed.

Sign in / Sign up

Export Citation Format

Share Document