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Both ferromagnetic (FM) and charge-ordered domain structures of [([La.sub.1-x][Pr.sub.x]).sub.0.67][Ca.sub.0.33]Mn[O.sub.3] thin film were detected by magnetic force microscopy (MFM) and electric force microscopy (EFM) operated at low temperatures near the peak resistance temperature ([T.sub.p]). The in-plane-like FM domains of submicrometer size emerge below [T.sub.p], and their magnetic interaction with an MFM tip becomes stronger as the temperature is reduced. Charge-ordered insulating regions have the strong electrostatic interaction with an EFM tip near [T.sub.p], and the interaction correlates well with the temperature dependence of resistivity of the film. Index Terms--Charge ordering, colossal magnetoresistance, EFM, low temperature, magnetic domain, MFM.

We report on the structural, electrical, and optical properties of 5% niobium doped TiO2 thin films grown on various substrates by pulsed laser deposition. The epitaxial anatase Nb:TiO2 film on LaAlO3 is shown to be an intrinsic transparent metal and its metallic property arises from Nb substitution into Ti site as evidenced by the Rutherford backscattering channeling result. In contrast, the rutile Nb:TiO2 thin films show insulating behaviors with 2–3 orders higher room temperature electrical resistivity and ∼30 times lower mobility. A blueshift in the optical absorption edge is observed in both phases, though of differing magnitude. [ABSTRACT FROM AUTHOR]

We have performed depth profile analyses of the lattice parameters in epitaxial thin films of La0.67Ca0.33MnO3 to understand the evolution of strain relaxation processes in these materials. The analyses were done using grazing incidence x-ray scattering on films of different thicknesses on (100)-oriented LaAlO3 with a lattice mismatch of -2%. We find that such films exhibit two and sometimes up to three in-plane strained lattice constants, corresponding to a slight orthorhombic distortion of the crystal, as well as near-surface lattice relaxation. As a function of film thickness, we find that the strain is in the same order of magnitude up to a thickness of 70–80 nm, after which the strain begins to relax towards the bulk value of the lattice parameters. In addition, we find a depth behavior in the strain which is consistent with the formation of nonuniformly strained islands in the sample. [ABSTRACT FROM AUTHOR]

We have studied the physical properties of epitaxial La[sub 0.67-x]Pr[sub x]Ca[sub 0.33]MnO[sub 3](LPCMO) (x=0.13, 0.20, 0.27) thin films under different type and degree of substrate induced biaxial strain. Films with thickness of 300, 600, and 1000 Å grown on crystalline NdGaO[sub 3] (negligible strain), LaAlO[sub 3] (compressive strain), and SrTiO[sub 3] (tensile strain) by pulsed laser deposition are examined. Our data suggest occurrence of metastable phase mixtures in these films, with the volume fractions controlled by strain. In particular, melting of the charge ordered phase is seen to occur in thin films on SrTiO[sub 3] at fields as low as 1 T, in the low temperature regime. The deviation of ρ(T) from the effective medium theory further indicates that LPCMO thin films cannot be described as simple metal–insulator mixtures. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Thin films of Sr[sub 2]FeMoO[sub 6] have been deposited on single-crystalline and polycrystalline SrTiO[sub 3] substrates by pulsed laser deposition from a stoichiometric target. In order to obtain high-quality films, the deposition parameters were systematically optimized. The films grown under optimized conditions show properties comparable to those of bulk Sr[sub 2]FeMoO[sub 6] single crystals. Surprisingly, polycrystalline films obtained by depositing on polycrystalline SrTiO[sub 3] substrates do not show any significant low-field magnetoresistance (MR), contrary to expectations for a spin-polarized material. However, after controlled annealing-induced alteration of the grain-boundary properties, a development of the low-field MR feature is clearly observed. The occurrence of the low-field MR is accompanied by nonlinearity in the current-voltage characteristics. These results are analyzed in the light of the prevalent understanding of the properties of this double perovskite material. [ABSTRACT FROM AUTHOR]

Discusses the preparation of superconducting thin films of y[sub1]-Ba[sub2]-Cu[sub3]-O[subx] with superconducting temperature and prepared by a laser deposition technique. Method used in film preparation; Effects of thermal stresses in the films; Composition of the film; Result of the x-ray powder diffraction of the films.

Deals with a study which investigated the mechanisms of optical response in superconducting YBaCO thin films and grain-boundary weak links. Experimental methods; Experimental results; Conclusions.

Presents a study that examined the fabrication of high quality epitaxial thin films on various substrates by pulsed-laser deposition using nitrogen oxide reactive gas. Similarities and dissimilarities of the superconducting and structural properties of the neodyminium compound thin films; Categories of substrates.

Presents a study which investigated film-substrate interactions of YBa[sub2]Cu[sub3]O[sub7-x] thin films grown by pulsed laser deposition on alkaline earth fluoride substrates. Experimental details; Results and discussion; Conclusion.

Studies the surface layers on superconducting thin films using an x-ray photoelectron spectroscopy. Importance of x-ray photoelectron spectroscopy; Overview on the experiment; Discussion on the result of the study.

Investigates the optical response of c-axis oriented crystalline yttrium-barium-copper-oxygen thin films on strontium titanate and magnesium oxide substrates. Pulse optical response; Components contributing the pulsed optical response; Thermal modelling for the pulsed optical response.

The Mn K edge X-ray absorption near edge structures (XANES) of Pr0.67Sr0.33MnO3 film (100 nm) on (001) LaAlO3 substrate was measured at different temperatures to probe the MnO6 octahedron distortion and corresponding electronic structure. The absorption of high temperature paramagnetic-insulator phase differed from that of the low temperature ferromagnetic-metal phase. The temperature-dependent absorption intensity of Mn K edge XANES was correlated with the relaxation of distorted MnO6 octahedron, which changed the crystal field acting on the Mn site and the related electronic structure and properties. At low temperature, the splitting of Mn majority eg orbitals decreased and the density of states above the Fermi level increased in the relaxed MnO6 octahedron, as reflected by a wider separation between two sub-peaks in the pre-edge XANES spectra. [ABSTRACT FROM AUTHOR]

Electrical and thermal conductivities of epitaxial, high-quality Ta-doped TiO2 (Ta:TiO2) thin films were experimentally investigated in the temperature range of 35–375 K. Structurally identified as the anatase phase, degenerate Ta doping leads to high electrical conductivity in TiO2, reaching >105 (Ω-m)−1 at 5 at. % of Ta, making it a potential candidate for indium-free transparent conducting oxides. In stark contrast, Ta doping suppresses the thermal conductivity of TiO2 via strong phonon-impurity scattering imposed by the Ta dopant which has a high mass contrast with Ti that it substitutes. For instance, the near-peak value shows a >50% reduction, from 9.0 down to 4.4 W/m-K, at just 2 at. % doping at 100 K. Interestingly, further Ta doping beyond 2 at. % no longer reduces the measured total thermal conductivity, which is attributed to a high electronic contribution to thermal conduction that compensates the alloy-scattering loss, as well as possibly the renormalization of phonon dispersion relation in the heavy doping regime originating from doping-induced lattice stiffening. As a result, at high Ta doping, TiO2 exhibits high electrical conductivity without much degradation of thermal conductivity. For example, near room temperature, 5 at. % Ta doped TiO2 shows over 3 orders of magnitude enhancement in electrical conductivity from undoped TiO2, but with only less than 10% reduction in thermal conductivity. The metallic Ta:TiO2 maintaining reasonable good thermal conductivity might find application in energy devices where good conduction to both charge and heat is needed. [ABSTRACT FROM AUTHOR]

The temperature dependent Schottky diode characteristics of epitaxial junctions between Nb:SrTiO3 (Nb concentrations: 0.5%) and Fe3O4 are studied. Epitaxial thin films of Fe3O4 were grown on Nb:SrTiO3 substrates by pulsed laser deposition technique. The films and heterointerfaces were characterized by x-ray diffraction, Z-contrast transmission electron microscopy, magnetic susceptibility, four-probe in-plane resistivity, and the temperature dependent junction current-voltage (I-V) characteristics. The nonlinear nature of the characteristics is analyzed within the framework of thermionic emission theory. Junction parameters such as the Schottky barrier height ([lowercase_phi_synonym]B) and ideality factor (η) are extracted. The temperature evolution of these parameters shows interesting and systematic trends, with remarkable changes near the Verwey transition (TV=120 K). The magnetic field dependence of I-V characteristic data is also recorded and a spin polarization of ∼80% is estimated for the magnetite electrode. [ABSTRACT FROM AUTHOR]

We report on the synthesis of low doping Zn1-xCoxO (0Al2O3 substrates. The films were prepared in an oxidizing atmosphere, using the pulsed-laser deposition technique starting from Zn and Co metallic targets. We first studied the influence of the strains of ZnO and their structural properties. Second, we investigated the structural and the magnetic properties of the Zn1-xCoxO films. We show that at low doping, the lattice parameters and the magnetization of the Zn1-xCoxO films depend strongly on the Co concentration. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents a study which reported an ex situ fabrication of gold contacts onto patterned YBa[sub2]Cu[sub3]O[sub7-x] films. Factors that complicate the formation of contacts to thin films; Advantages and disadvantages of in situ deposition of the contact metal through a mask; Disadvantages of the blanket coating of the HTSC with the contact metal.

Hafnium oxide (HfO2) thin films were deposited by the pulsed laser deposition (PLD) method on SiC substrates. The bandgap of HfO2 thin films was observed to be 5.8 eV. The chemical nature and stoichiometry of the films were analyzed by x-ray photoelectron spectroscopy (XPS). Metal-insulator-semiconductor (MIS) structures with Ni as a top electrode and TiN as a bottom electrode were fabricated to study the leakage current properties. The devices exhibited leakage current density of 50 nA/cm². The dielectric constant of these films is estimated to be in the range 17-24 from capacitance-voltage (C-V) measurements. The frequency dependence of the interface trapped charges is studied. [ABSTRACT FROM AUTHOR]

The recent discovery of ferromagnetism above room temperature in low-temperature-processed MnO2–ZnO has generated significant interest. Using suitably designed bulk and thin-film studies, we demonstrate that the ferromagnetism in this system originates in a metastable phase rather than by carrier-induced interaction between separated Mn atoms in ZnO. The ferromagnetism persists up to ∼980 K, and further heating transforms the metastable phase and kills the ferromagnetism. By studying the interface diffusion and reaction between thin-film bilayers of Mn and Zn oxides, we show that a uniform solution of Mn in ZnO does not form under low-temperature processing. Instead, a metastable ferromagnetic phase develops by Zn diffusion into the Mn oxide. Direct low-temperature film growth of Zn-incorporated Mn oxide by pulsed laser deposition shows ferromagnetism at low Zn concentration for an optimum oxygen growth pressure. Our results strongly suggest that the observed ferromagnetic phase is oxygen-vacancy-stabilized Mn2−xZnxO3−δ. [ABSTRACT FROM AUTHOR]

We report on the performance of a Ku-band gold/Ba0.5Sr0.5TiO3/LaAlO3 (Au/BSTO/LAO) coupled microstip line phase shifter fabricated with a 370 nm thick BSTO film. Two hundred degrees of contiguous relative insertion phase shift (ΔφS21), with insertion losses of 4.6 dB, were measured at room temperature, 14.3 GHz, and maximum dc voltage of 400 V. These results represent significant progress toward viable compact, low-loss, thin-film ferroelectric-based phase shifters at room temperature. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 20: 53–56, 1999. [ABSTRACT FROM AUTHOR]

Useful electronic, magnetic, and optical properties have been proposed and observed in thin films of Ti1-xMxO2 (M=Ta,Nb,V). In this work, we have studied phase formation for films of Ti1-xTaxO2 prepared by pulsed laser deposition. We show that substitutional Ta in TiO2 results in a different material system in terms of its electronic properties. Moss-Burstein shift is ruled out by comparing the electrical transport data of anatase and rutile TiO2. Vegard's law fit to the blueshift data and the high energy optical reflectivity studies confirm the formation of an alloy with a distinct band structure. [ABSTRACT FROM AUTHOR]

The authors performed a systematic study of the structural and electrical properties of Nb:TiO2 thin films by varying the substrate temperature (TS) and oxygen partial pressure (PO2). Niobium is found to incorporate easily and substitutionally into titanium lattice site as indicated by its low activation energy. By increasing TS, the carrier concentration (n) increases in the same way that niobium substitution fraction (s) increases, and the mobility increases as the structural quality is improved. With increasing PO2, n decreases dramatically though s does not change considerably. This may indicate that a large number of p-type native defects form, which “kill” the electrons produced by the Nb donors. [ABSTRACT FROM AUTHOR]

The authors report the epitaxial growth of cubic TaC thin films on 4H-SiC (0001) substrates by pulsed laser deposition and their recrystallization kinetics. The growth temperature for epitaxy was found to be 1000 °C. The activation energy for the recrystallization was 1.5 eV. High temperature annealing produced changes in the surface morphology which caused grain growth and created pinholes through a recrystallization process in the films deposited at lower temperatures. The films deposited at higher temperatures remained virtually unchanged. Implications of these results are discussed in the context of the development of future high temperature and high-power electronic devices. [ABSTRACT FROM AUTHOR]

Thin films of (0.5%, 1%) Nb:SrTiO3 dilutely doped with (2 at. %) magnetic transition elements (Cr, Co, Fe, Mn) are examined for ferromagnetism. X-ray diffraction, Rutherford backscattering ion channeling, scanning transmission electron microscopy Z-contrast imaging, and electron energy loss spectroscopy techniques establish high crystalline quality of the films with no impurity phase(s) and highly uniform dopant distribution. Although the film conductivity improves dramatically by Nb doping, no ferromagnetism is found in any of our samples over the temperature range of 365 down to 5 K. This is contrasted to the case of ferromagnetism reported in cobalt doped (La,Sr)TiO3. [ABSTRACT FROM AUTHOR]

Thin films of Nb-doped SrTiO3 (NSTO) are grown via pulsed laser deposition (PLD) on LaAlO3 (LAO,001), MgAl2O4 (MAO,001), SrTiO3 (STO,001), and Y-stabilized ZrO2 (YSZ,001) substrates. The effects of the film-substrate lattice mismatch, film thickness, and substrate temperature during growth on the film properties are investigated. The electrical transport in NSTO films is shown to exhibit a strong sensitivity to strain, which is suggested to arise from the dependence of carrier mobility on bond distortions/stretching and related changes in phonon modes. [ABSTRACT FROM AUTHOR]

It is shown that dilute niobium doping has a significant effect on the ferromagnetism and microstructure of dilutely cobalt-doped anatase TiO2 films. Epitaxial films of anatase TiO2 with 3% Co, without and with 1% niobium doping were grown by pulsed-laser deposition at 875°C at different oxygen pressures. For growth at 10-5 Torr niobium doping suppresses the ferromagnetism, while it enhances the same in films grown at 10-4 Torr. High-resolution Z-contrast scanning transmission electron microscopy and electron energy loss spectroscopy show uniform surface segregation of cobalt-rich Ti1-x-yCoxNbyO2-δ phase, but without cobalt metal clusters. [ABSTRACT FROM AUTHOR]

We report on the growth of highly oriented HfO2 thin films of monoclinic phase stabilized by 5% Co doping on (001) yttrium-stabilized zirconia (YSZ) using pulsed-laser deposition at 700 °C at an oxygen partial pressure of 10-4 Torr. On the other hand, pure HfO2 of such quality did not grow on YSZ in wide range of growth parameters. Rutherford backscattering-ion channeling in this film showed a 24% minimum yield (χmin) indicating highly oriented film growth, while hardly any ion channeling was observed in the undoped sample. High-resolution transmission electron microscopy revealed a sharp interface, and no signature of Co clusters. Electron energy loss spectroscopy showed that Co is in the 2+ state. Attempts were also made to grow films on a (001) Si substrate, and the results showed a very low ion channeling yield (∼8%). [ABSTRACT FROM AUTHOR]

Pulsed-laser-deposited polycrystalline/amorphous films of mixed-valent manganites [La0.7Ca0.3MnO3 (LCMO), La0.5Sr0.5MnO3 (LSMO), La0.5Ba0.5MnO3 (LBMO), and (La0.6Pr0.4)0.67Ca0.33MnO3 (LPCMO)] grown at low temperature (450 °C) on single crystal (001) silicon substrate are evaluated for uncooled bolometric applications. It is shown that the temperature coefficient of resistance (TCR) and electrical noise (Sυ) depend on the chemical composition. The optimum performance is found for LCMO with TCR of ∼7% K-1 and spectral noise ∼8.9 × 10-13 V²/Hz. In LBMO and LSMO the noise is much lower, but so is the TCR (1.5%-2% K-1). In LPCMO the TCR is high (∼10% K-1) and the noise is as well. [ABSTRACT FROM AUTHOR]

The effect of 200 MeV Ag ion irradiation on the temperature and field dependence of critical current density (J[sub C]) of high quality MgB[sub 2] thin films is studied. Substantial increase in J[sub C] is observed over a certain field range for the film irradiated at a dose of 10[sup 12] ions/cm[sup 2]. Our analysis suggests that columnar defects are not formed under irradiation conditions used in these studies, which correspond to an electronic energy loss of about 16 keV/nm. Defects clusters are likely to be responsible for the observed improvement in J[sub C].© 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Transparent conducting films of SnO[sub 2] are grown on single-crystal R-Al[sub 2]O[sub 3] substrates by the pulsed electron beam deposition (PED) technique, and their electrical, optical, and microstructural properties are compared with the films grown by pulsed-laser deposition (PLD). In PED, the pulsed electron beam used for ablation is generated by a channel-spark system with discharge voltage of 12 kV, current ∼1 kA, and pulse duration of ∼100 ns. The PED films are highly oriented, show good epitaxy, and are highly transparent with transmittance of ∼80% in the visible and IR range. The measured band gap is close to 3.9 eV. It is shown that the PED film properties compare well with those of PLD films, with the [sup 119]Sn Mossbauer spectroscopy showing comparable local environments in the two. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Thin films of 5% Co doped Cu[SUB2]O were grown on single-crystal (001) MgO substrates by pulsed-laser deposition, without and with 0.5% codoping with Al, V, or Zn. Structural, electrical, and magnetic properties were studied. The films showed phase-pure character under the chosen optimum growth conditions. Spin-glass-like behavior was observed in Co-doped films without codoping. A clear ferromagnetic signal at room temperature was found only in the case of Co:Cu[SUB2]O films codoped with Al. [ABSTRACT FROM AUTHOR]

We report on the realization of wide band gap (5-6 eV), single-phase, metastable, and epitaxial Mg[sub x]Zn[sub l-x]O thin-film alloys grown on sapphire by pulsed laser deposition. We found that the composition, structure, and band gaps of the Mg[sub x]Zn[sub 1-x]O thin-film alloys depend critically on the growth temperature. The structural transition from hexagonal to cubic phase has been observed for (Mg content greater than 50 at. %) (1 ≥x≥0.5) which can be achieved by growing the film alloys in the temperature range of 750 °C to room temperature. Interestingly, the increase of Mg content in the film has been found to be beneficial for the epitaxial growth at relatively low growth temperature in spite of a large lattice mismatch between sapphire and cubic MgZnO alloys. [ABSTRACT FROM AUTHOR]

We report on the fabrication and characterization of visible blind ultraviolet photodetectors based on Mg[sub x]Zn[sub 1-x]O. Using pulsed laser deposition technique, Mg[sub 0.34]Zn[sub 0.66]O thin films with a bandgap of 4.05 eV were epitaxially grown on c-plane sapphire substrates. The structural, electrical, and optical properties of epilayers were characterized using various techniques. Based on the Mg[sub 0.34]Zn[sub 0.66]O films, planar geometry photconductive type metal-semiconductor-metal photodetectors were fabricated. At a 5 V bias, a high responsivity of 1200 A/W was achieved at 308 nm, and the visible rejection (R308 nm/R400 nm) was more than four orders of magnitude. The 10%-90% rise and fall time were 8 ns and 1.4 μs, respectively. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Studies the influence of oxygen pressure on the epitaxy, surface morphology and optoelectronic properties of zinc oxide (ZnO) thin films grown on sapphire by pulsed-laser deposition. Rutherford backscattering and ion channeling in conjuction with atomic force microscopy; Impact of growth and defects on electron mobility, free-electron concentration and luminescence.

Studies the electronic structure and magnetic properties of La[sub 0.7]Sr[sub 0.3]MnO[sub 3] as a function of YBa[sub 2]Cu[sub 3]O[sub 7-delta] cap layer thickness. Use of x-ray absorption spectroscopy and x-ray magnetic circular dichroism techniques in the study.

Studies the effects of annealing and strain on La[sub 1-x]Ca[sub x]MnO[sub 3] thin films. Deposition of the thin films onto (100)-oriented LaAlO[sub 3] substrates using the pulsed laser deposition technique; Physical properties of the as-grown films.

Investigates the structural and physical properties and growth of thin films of neodymium[sub 0.5]strontium[sub .05]manganese oxygen[sub 3]. Film orientation; Dependence of transport properties on film thickness; Resistivities of the films with different thicknesses; Charge ordering transition and distortion of the lattice.

Reports that anomalously high metal-insulator transition temperature T[sub p] and ferromagnetic transition temperature T[sub c] have been observed in thin films of La[sub 0.8]Ca[sub 0.2]MnO[sub 3]. Ferromagnetic resonance signals from microwave studies observed at room temperature.

The microstructure of in situ epitaxially grown Y-Ba-Cu-O thin films on (001) SrTiO3 substrates was studied using cross-sectional transmission electron microscopy. The films, prepared by pulsed laser deposition at substrate holder temperature of 650 °C without post-annealing, exhibit zero resistivity above 90 K and critical currents exceeding 106 A/cm2 at 77 K. The films are of heavily faulted single crystalline structure with the c axis approximately perpendicular to the substrate (001) surface. We suggest that, due to the fast quenching and low substrate temperature, crystalline defects and chemical fluctuations are locked into a faulted structure after each laser pulse. Despite their rather imperfect microstructure, the films are free from macroscopic grain boundaries and secondary phases and possess superb superconducting properties. [ABSTRACT FROM AUTHOR]

We have grown ultrathin films of Y1Ba2Cu3O7-x in situ on (001) SrTiO3 by pulsed laser deposition. The zero resistance transition temperature (Tc0) is >90 K for films >300 Å thick. The critical current density (Jc at 77 K) is 0.8×106 A/cm2 for a 300 Å film and 4–5×106 A/cm2 for a 1000 Å film. The Tc0 and Jc deteriorate rapidly below 300 Å, reaching values of 82 K and 300 A/cm2 at 77 K, respectively, for a 100 Å film. Films only 50 Å thick exhibit metallic behavior and possible evidence of superconductivity without showing zero resistance to 10 K. These results are understood on the basis of the defects formed at the film-substrate interface, the density of which rapidly decreases over a thickness of 100 Å. We have studied these defects by ion channeling measurements and cross-section transmission electron microscopy. Our results suggest that the superconducting transport in these films is likely to be two dimensional in nature, consistent with the short coherence length along the c axis of the crystals. [ABSTRACT FROM AUTHOR]

Measurements of fast nonlinear switching of a high Tc superconducting thin film at 70 K between the dissipative state (induced by an electrical current) and superconducting state are reported. System rise and fall times are measured to be about 1 ns and are limited by the parasitic components of the electrical circuitry. A novel scheme for noise discrimination in digital circuits using this switching has been proposed and experimentally demonstrated for speeds exceeding 200 Mb/s. This method allows significant reduction of amplitude noise and improvement of signal-to-noise ratio in digital circuits. [ABSTRACT FROM AUTHOR]

Magnetotransport measurements on micron-sized wires of the thin-film high Tc superconductor Y1 Ba2 Cu3 O7-x made by pulsed laser deposition reveal an exponential suppression of the critical current with magnetic field, and a power law dependence of the critical current on reduced temperature. We ascribe this behavior to crystallographic defects in the film which behave as superconductor/normal-metal/superconductor weak links in a magnetic field. From the measurements we estimate a critical current density of 106 A cm-2 in a field of 16 T at 4.2 K. [ABSTRACT FROM AUTHOR]

By depositing YBaCuO films at low substrate holder temperatures (600 °C) using a pulsed laser, films with the orthorhombic phase exhibiting superconductivity with high zero resistance temperatures (Tc0) were produced. Tc0 values as high as 50 and 80 K were seen on films deposited directly on Si and on Si with only a 50 nm ZrO2 buffer layer, respectively. The key to the successful film deposition is the low processing temperatures involved, which minimized the interface reactions as observed by Auger electron spectrometry. [ABSTRACT FROM AUTHOR]

We report the first successful preparation of thin films of Y-Ba-Cu-O superconductors using pulsed excimer laser evaporation of a single bulk material target in vacuum. Rutherford backscattering spectrometry showed the composition of these films to be close to that of the bulk material. Growth rates were typically 0.1 nm per laser shot. After an annealing treatment in oxygen the films exhibited superconductivity with an onset at 95 K and zero resistance at 85 and 75 K on SrTiO3 and Al2O3 substrates, respectively. This new deposition method is relatively simple, very versatile, and does not require the use of ultrahigh vacuum techniques. [ABSTRACT FROM AUTHOR]

Focuses on the use of the pulsed laser deposition (PLD) technique in the United States. Industrial applications of PLD; Concept behind thin-film deposition; Benefits of PLD.

Examines the formation of multilayer high T[sub c] superconducting field-effect transistor-like structure from ultrathin YBa[sub 2]Cu[sub 3]O[sub 7-x] films. Modulation of the normal state properties; Resistance modulation of the films; Composition of the superconducting field-effect transistor.

Measures the residual loss in epitaxial YBa[sub 2]Cu[sub 3]O[sub 7] thin films from microwave to submillimeter wave frequencies. Use of weakly coupled superconducting grain model and a homogeneous two-fluid model.