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We have grown Bi0.9Sr0.1CuSeO epitaxial thin films on MgO and SrTiO3 (STO) single-crystal substrates by pulsed laser deposition (PLD) under various growth conditions, and investigated the crystal orientation, crystallinity, chemical composition, and thermoelectric properties of the films. The optimization of the growth conditions was realized in the film grown on MgO at the temperature T s = 573 K and Ar pressure P Ar = 0.01 Torr in this study, in which there was no misalignment apart from the c-axis and no impurity phase. It was clearly found that the higher crystal orientation of the epitaxial film grown at a higher temperature under a lower Ar pressure mainly enhanced the thermoelectric power factor P (= S 2/ρ), where S is the Seebeck coefficient and ρ is the electrical resistivity. However, the thermoelectric properties of the films were lower than those of polycrystalline bulk because of lattice distortion from lattice mismatch, a low crystallinity caused by a lower T s, and Bi and Cu deficiencies in the films.

Skutterudite compounds, SryCo4Sb12-xGex (y=0.3, x=0–0.3), are synthesized by a melting method. The effect of germanium doping on thermoelectric properties is investigated. Electrical conductivity, Seebeck coefficient, and thermal conductivity are measured from 300 to 850 K. The substitution of germanium is effective in reducing thermal conductivity while keeping excellent electrical transport properties owing to the high filling fraction of Sr and Ge doping as charge compensation. The dimensionless thermoelectric figure of merit ZT is observed to increase from 0.9 at 850 K for Sr0.28Co4Sb12 to 1.05 for Sr0.34Co4Sb11.9Ge0.1 at 850 K. These results suggest that doping with germanium is an attractive avenue to optimization of filled skutterudites.

Langmuir–Blodgett (LB) films of retinoic acid and LB films of retinoic acid mixed with a peptide that contains an alanine–lysine–valine (AKV) amino acid sequence deposited on a hydrogenated amorphous silicon (a-Si:H) film prepared by electron cyclotron resonance (ECR) plasma sputtering were fabricated, and their light absorption spectrums were compared. A specific visible light absorption at approximately 500 nm occurred in a film that had a film thickness of more than 80 nm and a hydrogen concentration of more than 20% in the sputtering process gas. Mixing the AKV sequence peptide with retinoic acid caused a 6 nm blueshift, from 363 to 357 nm, of the absorption maximum of the composite LB film on a SiO2 substrate. Using the same peptide, a large 30 nm blueshift, from 500 to 470 nm, was induced in the composite LB film on the a-Si:H film.

A plasma-enhanced co-polymerization technique was developed for low-k/Cu damascene integration on 300 mm wafers. This technique enables us to control dielectric film properties by introducing organo-siloxane and hydrocarbon into a He-plasma. The growth rate of the low-k film derived from divinyl siloxane–benzocyclobutene (DVS–BCB) as a matrix monomer is increased by adding C2H2 as a deposition acceleration monomer and the Young's modulus was enhanced by adding diisopropenylbenzene (DIPB) or divinylbenzene (DVB) as a reinforcement monomer. Cu damascene interconnects with plasma polymerized low-k films were successfully fabricated on 300 mm wafers.

Ba(Ti0.85Zr0.15)O3 films were prepared at 973 K on (100)Pt/(100)MgO substrates by metalorganic chemical vapor deposition (MOCVD), and their dielectric properties were investigated. The dielectric constant (e') of the film changed depending on the ac electric field (Eac) and frequency at temperatures below 400 K. The e' showed a broad maximum at a specific temperature (TM) that decreased from 370 to 330 K with increasing Eac from 0.15×105 to 15×105 Vm-1. The film exhibited ferroelectric characteristics with remanent polarization (2Pr) of 3×10-2 Cm-2 and coercive field (2EC) of 14×105 Vm-1.

Barium titanate zirconate (Ba(Ti1-xZrx)O3) films in the range of x=0 to 1.0 were prepared on (100)Pt/(100)MgO substrates at 973 K by metalorganic chemical vapor deposition (MOCVD). The effects of zirconium content (x) on the microstructure and dielectric properties of films were investigated. At x≤0.15, the Ba(Ti1-xZrx)O3 films showed highly crystallized and significant (001) orientation. The (001) orientation of the films decreased with increasing x, and the orientation became random at x>0.36. The dielectric constant of Ba(Ti1-xZrx)O3 films changed with x from 35 to 689 and showed a maximum at x=0.15. The remanent polarization (2Pr) and the coercive field (2EC) of Ba(Ti0.85Zr0.15)O3 film were 3 µCcm-2 and 14 kVcm-1, respectively. The onset electric field for nonohmic conduction of Ba(Ti1-xZrx)O3 film increased from 10 k to 1 MVcm-1 with increasing x.

An Ag-alloy (97Ag–1Pd–2Cu in mol%) was proposed as a new top-electrode for Pb(Zr, Ti)O3 (PZT) films. The effect of annealing temperature on the ferroelectric performance of PZT films using the Ag-alloy and Pt top-electrodes was investigated in a H2-containing atmosphere. In the case of the Pt top-electrode, the ferroelectricity of PZT films disappeared after annealing over 300°C. Exfoliations of the Pt bottom-electrode from the substrate were observed after annealing over 300°C. In the case of the Ag-alloy top-electrode, no chemical reaction between the Ag-alloy electrode and PZT film was observed after annealing at 400°C. The ferroelectricity of PZT film was maintained even after annealing at 350°C using the Ag-alloy electrode.

Li y CoO2 has a similar layered structure to Na y CoO2, which is a typical p-type oxide thermoelectric material, and the average Co valence of 3 + y is controlled by the Li content y. We investigated the thermoelectric properties of LiCo1− x M x O2 samples (M = Cu, Mg, Ni, Zn) for the first time at high temperatures, in which Co3+ was substituted by the divalent M2+ ions, and the average Co valence of 3 + x can be controlled similarly to the Li content y in Li y CoO2. The substitution of the M2+ ions for the Co site was found to show thermoelectric properties similar to those of Li y CoO2 with the same average Co valence. The Mg-doped sample showed the highest thermoelectric performance at high temperatures in this study; the thermoelectric power factor P is 2.38 × 10−4 W m−1 K−2 at 1173 K and the dimensionless figure of merit ZT is 0.024 at 876 K. The thermoelectric potential of LiCo1− x M x O2 is discussed and compared with those of Li y CoO2 and Na y CO2 systems.

We have investigated the ball milling effects for thermoelectric Bi1− x Sr x CuSeO materials. The characteristic rotation speed R for the ball milling exists, at which the crystallite size of the starting powder suddenly decreased. The grain size in the bulks sintered using ball-milled powders also decreased and thermoelectric properties were enhanced mainly by the induced carriers, rather than by the reduction in thermal conductivity. The ball milling effects of carrier doping on thermoelectricity are discussed.

Yttria-stabilized zirconia (YSZ) films were prepared by a laser Chemical vapor deposition (CVD) process. A plasma-like strong light emission was observed from a reaction zone around a substrate by laser irradiation. The deposition rates were significantly increased from 1 to 230 µm/h. The charges in the light-emitting zone consisted of mainly positive and negative ions, but electrons scarcely existed. The emitted light had a continuous spectrum similar to the Planck distribution.

A surface structural comparison of composite film of bacteriorhodopsin (BR) and phosphatidylcoline (PC) fabricated on a layered fatty acid film on a substrate of amorphous silicon dioxide (a-SiO2), crystal silicon dioxide (c-SiO2), or hydrogenated amorphous silicon (a-Si:H) was conducted to investigate the effect of substrate structure on the Langmuir–Blodgett (LB) film fabrication of membrane protein by direct force microscopy (DFM) measurement. On the a-SiO2 substrate, a hexagonal crystal structure of BR and PC with a size of 0.5 µm was observed. However, on the c-SiO2 or a-Si:H substrate, the surface structural features of the composite LB films differed from each other on the shape of assemblies in themselves. In spite of the presence of fatty acid layers, the assemby of BR and PC depends on the structure of the bottom substrate.

The electronic structure of Nd3+-substituted Bi4Ti3O12 single crystals was studied by soft-X-ray emission spectroscopy. The valence band is in good accordance with the band calculation. The valence band is mainly composed of the O 2p state hybridized with Ti 3d and Bi 6s states. The hybridization effect between the Ti 3d and O 2p states increases with Nd3+ substitution, indicating a change in Ti–O bond length in the a–b plane. The hybridization effect between the Bi 6s and O 2p states decreases with Nd3+ substitution. The Bi–O hybridization effect is considered to be closely related to the ferroelectric behavior.

Al–O–N films were prepared by electron cyclotron resonance plasma-assisted chemical vapor deposition (ECR PACVD) using an AlBr3–N2O–N2–Ar–H2 gas system. The structure, composition, deposition rate and optical properties were investigated. The compositions were controlled by changing the N2O/(N2O+N2) flow rate ratio (R). The refractive index was varied from 1.60 to 2.10, and the cutoff photon energy at 10% transmittance (E g/10) from 5.1 to 7.0 eV as the R changed from 0 to 1.0. The Al–O–N films were composed mainly of a mixture of Al2O3 and AlN. An aluminum oxynitride phase was also identified at R=0.2 to 0.53. The Al–O–N films contained a (001)-oriented hexagonal AlN phase at R=0.025, and the films were amorphous at R>0.05.

Cone-shaped silicon (Si) field-emitter arrays (FEAs) with 0.1-µ m-diameter gates were fabricated by focused ion beam (FIB) lithography. In the fabrication process, a 200 keV Be2+ FIB with a beam diameter of 0.06 µ m was irradiated to a positive-tone electron-beam resist to form an array of silicon oxide ( SiO x ) disks used as masks for cone-shape etching of a Si substrate. We have succeeded in the operation of the present FEA and obtained the emission current of 1 nA/tip at the gate voltage of 25 V.

Tungsten-bronze-type Ba2NaNb5O15 (BNN) thin films were deposited on fused-quartz and Si substrates. The deposition ratio (Ba:Na:Nb) and rate of the films depend on the sputtering conditions. The dielectric constant and dielectric loss factor are 889 and 0.029, respectively, at room temperature. The leakage current density is about 100 mA/cm2 at 1 MV/cm. The remanent polarization and coercive field are 2.39 µ C/cm2 and 8.33 kV/cm, respectively, and the second-harmonic generation coefficient d is about 2.54×10-13 m/V. Moreover, Raman scattering of the BNN films is discussed.

A film with tungsten-bronze structure was formed on a Pt/Al2O3 substrate by a RF msagnetron sputtering method. The deposition ratio of the films (Ba:Na:Nb) depended on the sputtering gas pressure. When the deposition rates were 10 nm/min at 10-1 Pa and 5 nm/min at 8 Pa, the dielectric constant and the dielectric loss factor were 141 and 0.02 at room temperature, respectively, and the remanent polarization P r and the coercive field E c were 32 µC/cm2 and 576 V/mm, respectively.

Single crystalline silicon was photochemically etched by synchrotron radiation (SR) in the presence of reactive species produced by microwave discharge. The etching gases were a mixture of SF6 and Ar. We attempted to introduce O2 gas in order to increase the area selectivity by protecting the nonirradiated area. It was found that the introduction of O2 molecules was very effective in depressing the etching of a nonirradiated area resulting in high area selectivity. Also an anisotropic feature of c-Si was obtained by addition of O2 molecules and submicron patterning was successfully performed using a stencil mask. The effect of O2 molecules was investigated by the measurement of the spectra of total electron yield and Auger electrons. It seems that the formation of an oxide layer on c-Si surface played an important role in the area-selective etching.

A Bi2O3-TiO2 phase diagram was determined using differential thermal analysis (DTA) apparatus. Bi4Ti3O12 (BIT) micalike single crystals grown by a flux method were clear and slightly grayish in color. Ferroelectric and dielectric properties of BIT crystals were observed from measurements of electric displacement vs electric field hysteresis loops and the dielectric constant. Also, the polarization switching characteristics of BIT crystals were investigated. The switching time and switching current density were read from the transient waveforms.

Polycrystalline and epitaxlal films of a layer-structured ferroelectric Bi4Ti3O12 in perovskite phases have been deposited on sapphire substrates by ECR plasma sputtering using a sintering ceramic target. The substrate temperature higher than 550°C is necessary to grow Bi4Ti3O12 films in the perovskite phase without post-thermal annealing. Bi4Ti3O12 films were epitaxially grown on C, A and R surfaces of a sapphire single crystal. Refractive indices of Bi4Ti3O12 films were determined from measurements of the Brewster angle, and the dielectric constant was measured at 1 kHz using an ADEX-221A LCR meter.

Y-Ba-Cu-O films were prepared on (100)MgO single crystal substrates by ECR plasma sputtering. As-deposited films without substrate heating were amorphous and electrically insulating. The amorphous film was crystallized to YBa2Cu3O7-x by postannealing at 930°C for 1 min in O2 gas, and the T c of the postannealed film was 70.5 K. The film prepared at the substrate temperature of 650°C was crystalline YBa2Cu3O7-x and the T c of the film without any postannealing was 73 K.