In-situ superconducting YBa2Cu3O7 thin films grown by ion beam co-deposition

1989 ◽  
Vol 43 (1-4) ◽  
pp. 393-397 ◽  
Author(s):  
J.H. James ◽  
B.J. Kellett ◽  
A. Gauzzi ◽  
B. Dwir ◽  
D. Pavuna
Keyword(s):  
Thin Films ◽  
Ion Beam

Nucleation and Early Growth of Sputtered thin Films

1970 ◽  
Vol 28 ◽  
pp. 516-517
Author(s):  
Dudley M. Sherman ◽  
Thos. E. Hutchinson
Keyword(s):  
Thin Films ◽  
Electron Beam ◽  
Ion Beam ◽  
Ion Source ◽  
Water Cooling ◽  
Stages Of Growth ◽  
Lens Assembly ◽  
Microscope Technique ◽  
Ion Beam Sputter Deposition

The in situ electron microscope technique has been shown to be a powerful method for investigating the nucleation and growth of thin films formed by vacuum vapor deposition. The nucleation and early stages of growth of metal deposits formed by ion beam sputter-deposition are now being studied by the in situ technique.A duoplasmatron ion source and lens assembly has been attached to one side of the universal chamber of an RCA EMU-4 microscope and a sputtering target inserted into the chamber from the opposite side. The material to be deposited, in disc form, is bonded to the end of an electrically isolated copper rod that has provisions for target water cooling. The ion beam is normal to the microscope electron beam and the target is placed adjacent to the electron beam above the specimen hot stage, as shown in Figure 1.

Electron Microscopy of Ion Deposited Thin Films of the Oxides of Titanium

1985 ◽  
Vol 62 ◽  
Author(s):  
A. B. Harker ◽  
D. G. Howitt ◽  
P. J. Hood ◽  
P. Kobrin
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Ion Beam ◽  
Phase 1 ◽  
Equilibrium Phase ◽  
Free Standing ◽  
Fine Mesh ◽  
Voltage Electron ◽  
Post Deposition

ABSTRACTThe reactive ion beam deposition of ceramic films onto unheated substrates can produce amorphous films with essentially molecular mixing. The annealing and hot isotatic pressing (hipping) of these films to produce crystalline phases have reproducable effects which are sensitive to the temperature and the density of the film. Experiments with titanium oxides indicate that it is principally the equilibrium phases that are formed and that hipping can be used to encourage the same transformations at lower temperatures.Thin films of titanium oxide close to the stoichiometry of TiO2 were deposited onto unheated substrates of sodium chloride. Some of the films were removed from the substrate by floating them off in water and the remainder were either annealed or hipped to induce crystallization. The anneals were performed either in air or argon and the hipping was done under an argon pressure of about twenty thousand pounds per square inch. Several of the free standing films were annealed in the same atmospheres on nickel grids. All the specimens were prepared for transmission electron microscopy by the same floating technique and were examined in a Philips 400 T.E.M. at 125 keV. The as deposited films were amorphous and showed no visible texture other than that derived from a small amount of porosity. The films were sufficiently conductive that they could be examined directly in the T.E.M. without carbon coating provided they were supported on a grid of fairly fine mesh. One specimen was also examined in the Kratos 1.5 MeV high voltage electron microscope at the National Center for Electron Microscopy. The specimen was annealed in vacuum using an in-situ hot stage to directly observe the behavior of the film.The post deposition annealing and hipping of these films reproducibly induced the crystallization of anatase below 800°C. This is the equilibrium phase [1] and the extent to which the films transformed and the morphology of the growing crystallites were determined principally by the film thickness. There was little difference between the responses of free standing films and films left on the salt substrate. They tended to transform at about the same temperature, which was reproduced in the in-situ hot stage experiment and the microsructures which formed were very similar. The dependence upon thickness was also reflected in all the microstructures of the different post deposition treatments and it was possible to complete the transformations that were very sluggish in some of the films by hipping them at the same temperatures.

In situ preparation of Y/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7-x/ thin films deposited by ion beam sputtering: preliminary results

1991 ◽  
Vol 27 (2) ◽  
pp. 2522-2524 ◽  
Author(s):  
S. Barbanera ◽  
F. Murtas ◽  
L. Scopa ◽  
V. Boffa ◽  
G. Paterno ◽  
...  
Keyword(s):  
Thin Films ◽  
Ion Beam ◽  
Ion Beam Sputtering ◽  
Preliminary Results ◽  
In Situ Preparation ◽  
Beam Sputtering

USE OF ION BEAM ANALYSIS TO STUDY IN SITU THE OXYGEN DIFFUSION AND INTERFACIAL TRANSFER COEFFICIENTS IN Y1Ba2Cu3O7-x THIN FILMS

2001 ◽  
Vol 15 (28n29) ◽  
pp. 1361-1369 ◽  
Author(s):  
J. GARCÍA LÓPEZ ◽  
J SIEJKA ◽  
Y. LEMAITRE ◽  
J. C. MAGE ◽  
B. MARCILHAC
Keyword(s):  
Thin Films ◽  
Nuclear Reaction ◽  
Oxygen Diffusion ◽  
Diffusion Rate ◽  
Ion Beam ◽  
Experimental Chamber ◽  
Transfer Coefficients ◽  
Oxygen Loss ◽  
Carbon Contamination

An experimental chamber was connected to the 2.5 MV Van de Graaff accelerator allowing in situ sample annealing at T ≤ 700° C and under pO 2 ranging from 10-8 to 1 bar. For the first time to our knowledge the 16 O (3 He ,α)15 O nuclear reaction has been employed to monitor in situ the oxygen loss and uptake in Y 1 Ba 2 Cu 3 O 7-x (YBCO) thin films as a function of oxygen pressure and temperature ( T ≤ 500° C ). The role played by the presence of carbon contamination on YBCO surface was elucidated. Using the 12 C(d,p) 13 C nuclear reaction the carbon loss was observed for T ≥ 250° C and it was associated with the oxygen loss enhancement in YBCO. It is found that in absence of carbon contamination, oxygen in-diffusion rate in YBCO is much faster than the out-diffusion rate, the later being surface reaction limited. The oxygen diffusion coefficients and the surface exchange coefficients of YBCO films have been evaluated. These results will be discussed in relation with the mechanism of high temperature YBCO thin film growth by cathodic sputtering and with the mechanism of the oxygen loss and/or uptake during the sample cooling.

Creation of stable nanoconstrictions in metallic thin films via progressive narrowing by focused-ion-beam technique and in situ control of resistance

2009 ◽  
Vol 86 (4-6) ◽  
pp. 639-641 ◽  
Author(s):  
J. Vincenc Oboňa ◽  
J.M. de Teresa ◽  
R. Córdoba ◽  
A. Fernández-Pacheco ◽  
M.R. Ibarra
Keyword(s):  
Thin Films ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Metallic Thin Films ◽  
In Situ Control ◽  
Beam Technique

Irradiation-Enhanced Second-Phase Precipitation in Zr-Fe Nanocrystalline Thin Films

2005 ◽  
Vol 908 ◽  
Author(s):  
Djamel Kaoumi ◽  
Arthur T. Motta ◽  
Robert C. Birtcher
Keyword(s):  
Thin Films ◽  
Electron Microscope ◽  
Ion Beam ◽  
Intermetallic Phase ◽  
Second Phase ◽  
Phase Precipitation ◽  
Fe Content ◽  
Diffraction Patterns ◽  
Nanocrystalline Thin Films

AbstractIn situ observations in a transmission electron microscope (TEM) were used to study ion-beam enhancement of second-phase precipitation in Zr-Fe nanocrystalline thin films. The free-standing films were prepared by co-sputter deposition with an Fe content of 1.2 at%. TEM diffraction analysis showed that only the hcp Zr crystal structure was present in the as-deposited films. No second phases were detected, although Rutherford Backscattering Spectroscopy (RBS) confirmed a Fe content beyond the solubility limit of Fe in Zr (of the order of ppm). This means the thin films were Zr solid solutions supersaturated with Fe. Heat treatment in the absence of irradiation was observed to cause precipitation of the Zr2Fe intermetallic phase, but only above 673 K. The same second-phase precipitation can occur at lower temperatures in the presence of ion irradiation. Samples were irradiated in-situ at the Intermediate Voltage Electron Microscope (IVEM) at Argonne National Laboratory with Kr ions to fluences in excess of 1016 ion/cm2, at temperatures ranging from 50 to 573 K. Second phase precipitation was detected by electron diffraction patterns and by dark field imaging comparing regions exposed to the beam with regions protected from the beam by the TEM support grid. Precipitation of Zr2Fe intermetallic phase was observed at all irradiating temperatures above room temperature. In the bulk, this phase is thermodynamically metastable in the range of temperatures investigated (relative to the orthorhombic Zr3Fe intermetallic phase). The kinetics of the irradiation-enhanced second-phase precipitation was followed by recording the diffraction patterns at regular intervals. The dose to precipitation was found to decrease with increasing irradiation temperature.

Deposition and characterization of YBa2Cu3O7−δ thin films grown in situ by sequential ion beam sputtering

1992 ◽  
Vol 7 (8) ◽  
pp. 2003-2016 ◽  
Author(s):  
J.A. Kittl ◽  
W.L. Johnson ◽  
C.W. Nieh
Keyword(s):  
Thin Films ◽  
Ion Beam ◽  
Film Surface ◽  
Lattice Expansion ◽  
Ion Beam Sputtering ◽  
Orientation Relations ◽  
Deposition Parameters ◽  
Beam Sputtering ◽  
Lattice Distortions

We investigated the in situ growth of YBa2Cu3O7−δ superconducting thin films by a sequential ion beam sputtering technique, studying the relations among deposition parameters, structural and superconducting properties. The films were deposited following the stacking sequence of YBa2Cu3O7−δ, with individual layer thicknesses nominally equal to one monolayer. O2 was supplied during deposition. Predominantly c-axis oriented films were grown on (100) SrTiO3, (100) MgO, and oxidized Si (SiO2/Si) substrates. The microstructure and film-substrate orientation relations were studied by transmission electron microscopy. X-ray studies showed the presence of homogeneous and inhomogeneous strains along the c-direction that persisted after low temperature oxygen anneals. Resistivity measurements showed correlations between the superconducting transition characteristics and the lattice distortions along the c-direction. The effect of deposition parameters on the lattice distortions was investigated, finding that the c-axis lattice parameter was larger in films grown at lower temperatures. This was interpreted in terms of the thermally activated dissociation of O2 at the film surface during growth. We assumed that the c-axis lattice expansion was due to kinetic limitations to the incorporation of oxygen into the film during growth. This led to a consistent description of the results obtained in this work and the O2 pressure dependence of the c-axis lattice expansion reported for other in situ techniques. Studies were performed on films grown by this technique as well as on films grown in situ by magnetron sputtering in an attempt to elucidate the nature of the defect structure causing the c-axis lattice distortions.

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