Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Substrate effects on the structure of epitaxial PbTiO3 thin films prepared on MgO, LaAlO3, and SrTiO3 by metalorganic chemical-vapor deposition (1995)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 78 (1995), S. 2607-2622 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Epitaxial PbTiO3 films were prepared by metalorganic chemical-vapor deposition on MgO(001)-, SrTiO3(001)-, and LaAlO3(001)-oriented substrates. Four-circle x-ray diffraction, transmission electron microscopy, Rutherford backscattering (RBS) channeling, and optical waveguiding were performed to characterize the deposited films. Epitaxial, single-crystal films were obtained on all three substrate materials under the same growth conditions. However, the defect structure of the films, including grain tilting, threading dislocation density, and 90° domain formation, was strongly dependent on the choice of substrate material. Films grown on MgO(001) and LaAlO3(001) (pseudocubic indices) substrates are nominally c-axis oriented; however, the PbTiO3 grains in the film form a fourfold domain structure, with the grains tilted ∼0.6° and ∼0.7°, respectively, toward the [100] directions (cubic or pseudo-cubic) of the substrates. In addition, these films contain a significant volume fraction of 90°-domain (a-axis) structures with a critical thickness hc for domain formation below the detection level of our experiments (hc≥100 A(ring)). Together, these structural defects result in a low RBS channeling yield reduction. In contrast, films grown on SrTiO3(001) substrates showed no tilting of the c-axis grains and a minimum RBS channeling yield of as low as ∼3%. In addition, we observed that below a critical film thickness of hc∼1500 A(ring), 90° domain formation was completely suppressed resulting in a nearly perfect single-crystal structure.The refractive indices and optical birefringence of the films were measured as a function of wavelength using the film-prism coupling method. Both the ordinary and extraordinary refractive indices for films grown on MgO(001) and LaAlO3(001) were higher than that of single-crystal PbTiO3; however, the optical birefringence of films grown on MgO(001) was reduced from that of the bulk. For films grown on SrTiO3(001), the ordinary refractive index was very close to that of single-crystal PbTiO3. We correlate the refractive index values and the reduced birefringence to the degree of residual strain and the volume fraction of 90° domains in the samples, respectively. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.360121
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Sputter-induced grain boundary junctions in YBa2Cu3O7−x thin films on MgO (1995)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 77 (1995), S. 2591-2594 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A low voltage argon ion sputter technique was used to form grain boundary junctions in YBa2Cu3O7−x thin films on MgO. The YBa2Cu3O7−x thin film grown on a pre-sputtered region of MgO was rotated 45° about the [001] axis relative to the YBa2Cu3O7−x thin film grown on an adjacent unsputtered region of the substrate. YBa2Cu3O7−x thin films were grown using pulsed organometallic beam epitaxy (POMBE). The current-voltage and resistance-temperature characteristics of individual grain boundary junctions demonstrated weak-link-type behavior. Sputter-induced 45° grain boundary junctions are advantageous in device applications because they are planar and simple to form in many configurations. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.358721
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Microstructural origin of 1/f noise in high Tc bicrystal SQUID magnetometers (1997)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 71 (1997), S. 3703-3705 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The origin of noise in YBa2Cu3O7−x (YBCO) bicrystal SQUID magnetometers on SrTiO3 substrates is investigated by comparing the microstructure of actual low-noise and high-noise devices. The most obvious difference in the microstructure is the presence of a-axis oriented particles in the high-noise devices, whereas the low-noise devices consist exclusively of c-axis oriented YBCO films. The growth of the a-axis particles in the YBCO films induces many defects, including amorphous regions, distortion in c-axis lattice planes and extra a-c interfaces. The quality of the junction boundary is also degraded by the a-axis particles. The existence of these defects are expected to affect the superconducting current and the motion of the magnetic flux in the films and hence generate extra noise in the devices. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.120487
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Integrated multilayer sputter-induced 45° YBa2Cu3O7−x grain boundary junctions (1995)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 67 (1995), S. 1013-1015 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A versatile multilayer technique has been developed to form 45° YBa2Cu3O7−x [001] tilt grain boundary junctions on LaAlO3 substrates. An epitaxial MgO layer is initially deposited on a (100) LaAlO3substrate using pulsed organometallic beam epitaxy (POMBE). After a pregrowth sputter treatment, an YBa2Cu3O7−x thin film is then grown using POMBE. The resultant film is c-axis oriented with a cube-on-cube orientation over the unsputtered portion of the MgO, and rotated by 45° about the [001] axis on the sputtered region of the substrate. The resulting grain boundary junction shows weak-link behavior. The advantage of this technique is the ability to place the grain boundary anywhere on the substrate in any configuration, and the potential to use any substrate upon which MgO can be epitaxially grown. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.114714
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Effect of annealing on superconductivity of Pb-doped Bi-Sr-Ca-Cu-O single-crystal superconductors (1990)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 57 (1990), S. 1693-1695 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The microstructure of high quality Pb-doped Bi2Sr2CaCu2Ox single crystals grown by the flux technique has been studied by transmission electron microscopy (TEM). The single crystals have a superconducting transition temperature (Tc) of about 90 K as grown; Tc drops to about 83 K after annealing in air at 600 °C. TEM results show that the as-grown crystals exhibit twinning. The twin boundaries were found to be parallel to the (100) and (010) lattice planes. However, upon annealing the twin structure disappeared. This microstructure change is discussed in terms of a possible cause for the Tc decrease in the annealed crystals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.104139
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    In-plane orientation control of (001)YBa2Cu3O7−δ grown on (001)MgO by pulsed organometallic beam epitaxy (1996)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 68 (1996), S. 3037-3039 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Thin films of (001) YBCO are grown on epitaxially polished (001) MgO by pulsed organometallic beam epitaxy. The in-plane orientation of the film is controlled by the thickness of a BaO layer, grown in situ, prior to the YBCO growth. For thin BaO layers (〈≈7×1014 Ba/cm2) the films grown [110]YBCO(parallel)[100]MgO. For thick BaO layers ((approximately-greater-than)≈11×1014 Ba/cm2) the films grow [100]YBCO(parallel)[100]MgO. A mechanism that relates the change in YBCO in-plane orientation to a change in the structure of the initial BaO layers with BaO thickness is described. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.115569
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    The chemical composition of a metal/ceramic interface on an atomic scale: The Cu/MgO {111} interface (1993)
    Springer
    Interface science 1 (1993), S. 61-75 
    Details
    ISSN: 1573-2746
    Keywords: Metal/ceramic interface ; internal oxidation ; Cu/MgO heterophase interface ; high resolution electron microscopy ; atom-probe field-ion microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The chemical composition profile across a Cu/MgO {111}-type heterophase interface, produced by the internal oxidation of a Cu(Mg) single-phase alloy at 1173 K, is measured via atom-probe field-ion microscopy with a spatial resolution of 0.121 nm; this resolution is equal to the interplanar spacing of the {222} MgO planes. In particular, we demonstrate directly that the bonding across a Cu/MgO {111}-type heterophase interface, along a 〈111〉 direction common to both the Cu matrix and an MgO precipitate, has the sequence Cu|O|Mg... and not Cu|Mg|O...; this result is achieved without any deconvolution of the experimental data. Before determining this chemical sequence, it was established, via high-resolution electron microscopy, that the morphology of an MgO precipitate in a Cu matrix is an octahedron faceted on {111} planes with a cube-on-cube relationship between a precipitate and the matrix; that is, {111}Cu//{222}MgO and 〈110〉Cu // 〈110〉MgO.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00203266
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...