[en] Solid solutions were prepared encompassing the entire composition range between LaTiO³ and GdTiO³. An anomaly in the magnetization-temperature data associated with magnetic ordering within the Ti₃⁺ sublattice was observed for the phases La_0.5Gd_0.5TiO³-LaTiO³ . La_0.3Gd_0.7TiO³-GdTiO³ appear to be two sublattice ferrimagnets. Anomalies in the magnetization-temperature curves observed for the compositions La_0.6Gd_0.4TiO³-La_0.8Gd_0.2TiO³ are consistent with spin glass behavior. The saturation magnetization of GdTiO³ at 4.2K was measured to be 5.8 +/- 0.2 μ_Bformula unit. Susceptibility data analyzed using the mean field model show a dramatic decrease in the strength of the ferromagnetic Ti₃⁺-Ti₃⁺ exchange on the dilution of the Gd₃⁺ sublattice by event 5% La₃⁺

[en] Transmission electron microscopy (TEM) and transmission electron diffraction (TED) studies have shown the presence of long range CuPt-type cationic ordering in GaInP grown by MOCVD on (001) GaAs. Domains regions (on order of 10⁴nm²) exhibit a double periodicity along the [111] and [111] directions

[en] The microstructure of polycrystalline thin films CuInSe₂ is investigated by spectrophotometry, x- ray diffraction, and transmission electron diffraction as a function of composition and relevant processing parameters. The inter- and intra-granular microstructure is defined as a compositionally and temperature dependent polycrystalline aggregate mixture of CuInSe₂ and Cu_xSe/In_ySe minor phases at intra-granular and grain boundary positions. The core crystallite exhibits order-disorder and a CuInSe₂-CuIn₂Se_3.5 phase separation and/or solid solution. The implications on the device performance are dependent on the extent of band-bending and interface states at phase boundaries, and on the filling extent of minor phase precipitates. The Cu-poor CuIn₂Se_3.5 phase may be suitable for device application

[en] This paper reports epitaxial InAs layers were grown by molecular beam epitaxy (MBE) on GaAs substrates. The initial stages of nucleation have been studied by in situ reflection high energy electron diffraction (RHEED). Cross-sectional TEM examination was used to investigate the morphology of the growing layer, while plan-view examination revealed the generation of misfit dislocations. The growth mode was found to depend mainly on the conditions used to nucleate the epitaxial layer. In most cases, Stranski-Krastanov type of growth was observed

[en] Epitaxial InAs:Sn is grown on semi-insulating GaAs substrates by molecular-beam epitaxy. The large lattice mismatch between these materials (/similar to/7.1%) generates a high density of threading dislocations which propagate into the epitaxial film. Both plan-view and cross-sectional transmission electron microscopy techniques are used to investigate the generation and propagation of these dislocations. For films that exceed the critical thickness, the threading dislocation density is inversely proportional to the epilayer thickness. Epitaxial layers incorporating growth interrupts have lower overall defect densities, yet maintain defect reduction profiles similar to those observed in layers grown without the growth interrupt. Room-temperature mobilities for InAs:Sn epitaxial layers varied from 11 200 to 22 100 cm²/V s for epilayer thicknesses of 0.4 to 4.4 μm, respectively. The thickness dependence on the mobility is attributed to a multiplicity of factors including surface scattering, interfacial strain, surface accumulation, and the high interfacial dislocation density

[en] Single-target RF magnetron sputtering was used to deposit superconducting thin films of Bi-Sr-Ca-Cu-O with a T/sub c/₀ above 80 K. Varying P/sub =/ modified the concentrations of Bi, Cu, and O in the films by 10%--20%. Higher annealing temperatures, especially with brief melting, favored the formation of the higher T/sub c/ phases. Tetragonal phases (6- and 75-K T/sub c/ ), with a = 3.8097 A, c = 24.607 A, and Bi₂ Sr₂ CuO₆ composition, and a = 3.812 A, c = 30.66 A, and Bi₂ Sr/sub 2-//sub x/ Ca/sub 1+//sub x/ Cu₂ O₈ composition, were identified. 70--84 K films contained large proportions of a new tetragonal phase, with a = 3.81 A and c = 55.23 A

[en] This paper reports on the feroelectric domain structure in sputtered lead zirconate titanate (PZT) thin films investigated using transmission electron microscopy (TEM) and transmission electron diffraction (TED). The individual ferroelectric domains occur as (110)-type microtwins as is observed in the bulk ceramic. The arrangement and size of the ferroelectric domains is strongly dependent on the microstructure of the sputtered film

[en] We have grown crystalline thin films of LaAlO₃ using off-axis rf sputtering from a single stoichiometric target. The films grow epitaxially on SrTiO₃ and LaAlO₃ (100) substrates as well as on YBa₂Cu₃O₇ thin films. We report on the growth conditions used to make these films, the properties of the films, and the properties of bilayer and trilayer structures containing both LaAlO₃ and YBa₂Cu₃O₇ films. Transmission electron microscopy cross-sectional and x-ray diffraction analyses indicate that all the constituent films in the multilayers grow epitaxially and that the interfaces between the films are sharply defined. Preliminary transport measurements on these multilayers show that LaAlO₃ can be used for dielectric layers in a variety of high-temperature superconductor electronic circuits