Investigation of ultra-thin films of YBa2Cu3O7−δ grown on MgO

1990 ◽  
Vol 48 (4) ◽  
pp. 6-7
Author(s):  
S.K. Streiffer ◽  
C.B. Eom ◽  
J.C. Bravman ◽  
T.H. Geballet
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Deposition Process ◽  
Nucleation And Growth ◽  
Multilayer Structures ◽  
Rf Power ◽  
Oxygen Loss ◽  
Transmission Electron ◽  
Single Target ◽  
Mtorr Argon

The study of very thin (<15 nm) YBa2Cu3O7−δ (YBCO) films is necessary both for investigating the nucleation and growth of films of this material and for achieving a better understanding of multilayer structures incorporating such thin YBCO regions. We have used transmission electron microscopy to examine ultra-thin films grown on MgO substrates by single-target, off-axis magnetron sputtering; details of the deposition process have been reported elsewhere. Briefly, polished MgO substrates were attached to a block placed at 90° to the sputtering target and heated to 650 °C. The sputtering was performed in 10 mtorr oxygen and 40 mtorr argon with an rf power of 125 watts. After deposition, the chamber was vented to 500 torr oxygen and allowed to cool to room temperature. Because of YBCO’s susceptibility to environmental degradation and oxygen loss, the technique of Xi, et al. was followed and a protective overlayer of amorphous YBCO was deposited on the just-grown films.

Dark-field imaging of ultrathin films of YBa2Cu3O7-δ grown on MgO

1991 ◽  
Vol 49 ◽  
pp. 1070-1071
Author(s):  
S.K. Streiffer
Keyword(s):  
Ultrathin Films ◽  
Deposition Process ◽  
Dark Field ◽  
Rf Power ◽  
Dark Field Imaging ◽  
Transmission Electron ◽  
Nominal Thickness ◽  
Single Target ◽  
Field Imaging ◽  
Oriented Single Crystal

The study of very thin (<15 nm) YBa2Cu3O7-δ (YBCO) films is necessary both for investigating the nucleation and growth of this material and for achieving a better understanding of multilayer structures incorporating such thin YBCO regions. We have used dark-field transmission electron microscopy to examine the structure of ultrathin films grown on MgO substrates by single-target, off-axis magnetron sputtering; details of the deposition process have been reported elsewhere, Briefly, polished, [001]-oriented, single crystal MgO substrates were attached to a block placed at 90° to the sputtering target and heated to 670 °C. The sputtering was performed in 40 mtorr oxygen and 170 mtorr argon with an rf power of 125 watts. Films were grown to a nominal thickness of one unit cell, or 1.2 nm. After deposition, the chamber was vented to 500 torr oxygen and allowed to cool to room temperature.

Interface motion during recrystallization of amorphous NiSi2

1990 ◽  
Vol 48 (4) ◽  
pp. 524-525
Author(s):  
J. L. Batstone ◽  
D.A. Smith
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Amorphous Film ◽  
Nucleation And Growth ◽  
Recrystallization Process ◽  
Amorphous Films ◽  
Interface Motion ◽  
Si Substrates ◽  
Spherical Caps ◽  
Crystal Interfaces

Recrystallization of amorphous NiSi2 involves nucleation and growth processes which can be studied dynamically in the electron microscope. Previous studies have shown thatCoSi2 recrystallises by nucleating spherical caps which then grow with a constant radial velocity. Coalescence results in the formation of hyperbolic grain boundaries. Nucleation of the isostructural NiSi2 results in small, approximately round grains with very rough amorphous/crystal interfaces. In this paper we show that the morphology of the rccrystallizcd film is dramatically affected by variations in the stoichiometry of the amorphous film.Thin films of NiSi2 were prepared by c-bcam deposition of Ni and Si onto Si3N4, windows supported by Si substrates at room temperature. The base pressure prior to deposition was 6 × 107 torr. In order to investigate the effect of stoichiomctry on the recrystallization process, the Ni/Si ratio was varied in the range NiSi1.8-2.4. The composition of the amorphous films was determined by Rutherford Backscattering.

Device quality InOx:Sn and InOx thin films deposited at room temperature with different rf-power densities

2012 ◽  
Vol 526 ◽  
pp. 221-224 ◽  
Author(s):  
A. Amaral ◽  
P. Brogueira ◽  
O. Conde ◽  
G. Lavareda ◽  
C. Nunes de Carvalho
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Rf Power ◽  
Power Densities

Local Structure and Er3+ Emission from Pseudo-Amorphous GaN:Er Thin Films

1998 ◽  
Vol 536 ◽  
Author(s):  
S. B. Aldabergenova ◽  
M. Albrecht ◽  
A. A. Andreev ◽  
C. Inglefield ◽  
J. Viner ◽  
...  
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Amorphous Matrix ◽  
Broad Band ◽  
Resonant Absorption ◽  
Absorption Bands ◽  
Host Matrix ◽  
Transmission Electron ◽  
Infra Red ◽  
Band Edge Luminescence

AbstractWe report on strong Er3+ luminescence in the visible and infra-red regions at room temperature in amorphous GaN:Er thin films prepared by DC magnetron co-sputtering. The intensity of the Er3+ luminescence at 1.535 μm corresponding to 4I13/2 → 4I15/2 transitions is greatly enhanced after annealing at 750°C. In this material GaN crystallites have formed and embedded in the continuous amorphous matrix. The crystallites are 4 to 7 nm in diameter as analyzed by high resolution transmission electron microscopy. The absorption edge, extending three orders of magnitude in absorption coefficient in the spectral range from 0.5 to 3.5 eV, is superimposed on resonant absorption bands of Er3+ ions.The total photoluminescence spectrum consists of welldefined Er3+ luminescence peaks imposed on a broad band edge luminescence from the amorphous GaN host matrix.

Multi-Component ZnO-In2O3-SnO2Thin Films Deposited by RF Magnetron Co-Sputtering

2007 ◽  
Vol 124-126 ◽  
pp. 119-122 ◽  
Author(s):  
Chang Sik Son ◽  
Jae Sung Hur ◽  
Byoung Hoon Lee ◽  
Sang Yul Back ◽  
Jeong Seop Lee ◽  
...  
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Visible Range ◽  
Rf Power ◽  
Working Pressure ◽  
Average Transmittance ◽  
Sno2 Thin Films ◽  
Ar Gas ◽  
Sputtering System ◽  
High Chemical Stability

Multi-component ZnO-In2O3-SnO2 thin films have been prepared by RF magnetron co-sputtering using targets composed of In4Sn3O12(99.99%) [1] and ZnO(99.99%) at room temperature. In4Sn3O12 contains less In than commercial ITO, so that it lowers cost. Working pressure was held at 3 mtorr flowing Ar gas 20 sccm and sputtering time was 30 min. RF power ratio [RF1 / ( RF1 + RF2 )] of two guns in sputtering system was varied from 0 to 1. Each RF power was varied 0~100W respectively. The thicknesses of the films were 350~650nm. The composition concentrations of the each film were measured with EPMA and AES. The low resistivity of 1-2 × 10-3 and an average transmittance above 80% in the visible range were attained for the films over a range of δ (0.3 ≤ δ ≤ 0.5). The films also showed a high chemical stability with time and a good uniformity.

Structural Evolution Upon Annealing of Multi-Layer Si/Fe Thin Films Prepared by Magnetron Sputtering

2007 ◽  
Vol 561-565 ◽  
pp. 1161-1164
Author(s):  
Xiao Na Li ◽  
Bing Hu ◽  
Chuang Dong ◽  
Xin Jiang
Keyword(s):  
Thin Films ◽  
Magnetron Sputtering ◽  
Room Temperature ◽  
Structural Evolution ◽  
Radio Frequency Magnetron Sputtering ◽  
Transmission Electron ◽  
Direct Band ◽  
The Stability ◽  
Sputtering System

Fe/Si multi-layer films were fabricated on Si (100) substrates utilizing radio frequency magnetron sputtering system. Si/β-FeSi2 structure was found in the films after the deposition. Structural characterization of Fe-silicide sample was performed by transmission electron microscopy, to explore the dependence of the microstructure of β-FeSi2 film on the preparation parameters. It was found that β-FeSi2 particles were formed after the deposition without annealing, whose size is less than 20nm ,with a direct band-gap of 0.94eV in room temperature. After annealing at 850°C, particles grow lager, however the stability of thin films was still good.

Effects of Dopants on the Nucleation and Growth of NiSi2 on Silicon

1987 ◽  
Vol 94 ◽  
Author(s):  
S. W. Lu ◽  
C. W. Nieh ◽  
J. J. Chu ◽  
L. J. Chen
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Low Temperatures ◽  
Nucleation And Growth ◽  
The Other ◽  
Size Factor ◽  
Atomic Size ◽  
Nickel Thin Films ◽  
Transmission Electron

ABSTRACTThe influences of implantation impurities, including BF2, B, F, As and P on the formation of epitaxial NiSi2 in nickel thin films on ion-implanted silicon have been investigated by transmission electron microscopy.The presence of BF2, B, and F atoms was observed to promote the epitaxial growth of NiSi2 at low temperatures. Little or no effect on the formation of NiSi2 was found in samples implanted with As or P ions.The results indicated that the influences of the implantation impurities are not likely to be electronic in origin. Good correlation, on the other hand, was found between the atomic size factor and resulting stress and NiSi2 epitaxy at low temperatures.

Nucleation, growth, and structure of Al–Mn quasicrystalline thin films prepared by high-temperature vapor deposition

1992 ◽  
Vol 7 (5) ◽  
pp. 1115-1125 ◽  
Author(s):  
P.B. Barna ◽  
A. Csanády ◽  
U. Timmer ◽  
K. Urban
Keyword(s):  
Thin Films ◽  
Vapor Deposition ◽  
Growth Process ◽  
Depth Profiling ◽  
Nucleation And Growth ◽  
Quasicrystalline Phase ◽  
X Ray ◽  
Transmission Electron ◽  
Mn Diffusion ◽  
High Temperature Vapor

The nucleation and growth of quasicrystalline thin films during sequential vapor deposition of aluminum and manganese on various substrates have been studied at temperatures between 530 and 650 K. The films were analyzed by transmission electron microscopy, electron diffraction, energy dispersive x-ray analysis, replica techniques, and Auger depth profiling. The quasicrystalline phase is identified as icosahedral. It nucleates on the surfaces of the Al films. There is no indication of substantial bulk Mn diffusion. The growth process is governed by diffusion of Al to the quasicrystal surface where it reacts with the incident Mn.

(111)p microtwinning in SrRuO3 thin films on (001)p LaAlO3

2009 ◽  
Vol 65 (6) ◽  
pp. 694-698 ◽  
Author(s):  
Y. Han ◽  
I. M. Reaney ◽  
D. S. Tinberg ◽  
S. Trolier-McKinstry
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Orientation Relationship ◽  
Room Temperature ◽  
Pulsed Laser ◽  
Zone Axis ◽  
Laser Deposition ◽  
Transmission Electron ◽  
Diffraction Patterns

SrRuO3 (SRO) thin films grown on (001)p (p = pseudocubic) oriented LaAlO3 (LAO) by pulsed laser deposition have been characterized using transmission electron microscopy. Observations along the 〈100〉p directions suggests that although the SRO layer maintains a pseudocube-to-pseudocube orientation relationship with the underlying LAO substrate, it has a ferroelastic domain structure associated with a transformation on cooling to room temperature to an orthorhombic Pbnm phase (a − a − c + Glazer tilt system). In addition, extra diffraction spots located at ±1/6(ooo)p and ±1/3(ooo)p (where `o' indicates an index with an odd number) positions were obtained in 〈110〉p zone-axis diffraction patterns. These were attributed to the existence of high-density twins on {111}p pseudocubic planes within the SrRuO3 films rather than to more conventional mechanisms for the generation of superstructure reflections.

Reactive Sputtering Growth and Characterizations of InN Thin Films on Si Substrates

2012 ◽  
Vol 545 ◽  
pp. 290-293
Author(s):  
Maryam Amirhoseiny ◽  
Hassan Zainuriah ◽  
Ng Shashiong ◽  
Mohd Anas Ahmad
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Rf Magnetron Sputtering ◽  
Rf Power ◽  
X Ray Diffraction ◽  
Nitrogen Gas ◽  
X Ray ◽  
Force Microscopy ◽  
Si Substrates ◽  
Atomic Force

We have studied the effects of deposition conditions on the crystal structure of InN films deposited on Si substrate. InN thin films have been deposited on Si(100) substrates by reactive radio frequency (RF) magnetron sputtering method with pure In target at room temperature. The nitrogen gas pressure, applied RF power and the distance between target and substrate were 2×10-2 Torr, 60 W and 8 cm, respectively. The effects of the Ar–N2 sputtering gas mixture on the structural properties of the films were investigated by using scanning electron microscope, energy-dispersive X-ray spectroscopy, atomic force microscopy and X-ray diffraction techniques.

Sign in / Sign up

Export Citation Format

Share Document