In this study, PZT thin films with different compositions were deposited by a chemical solution deposition on Si wafer with or without Electric-Field-Assisted Annealing (EFA-A) for the easy control of domain switching by Atomic Force Microscope (AFM) to develop the advanced memory. As a result, it was demonstrated that the EFA-A was very effective to enhance the electrical properties of the PZT thin films and the coercive field of the resulting PZT thin films increased with increasing amount of Ti concentration. Therefore, we tried to switch the domain structure of the PZT thin films with a Zr/Ti ratio of 30/70 annealed with EFA-A by AFM to exhibit the possibility of the direct domain writing in the CSD-derived PZT thin film for the advanced AFM memory.

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Concerning the ferroelectric films produced by AD method, the effects by adding auxiliary agents to injection powder and the effects by grain size were investigated for the purpose of realizing higher ferroelectric property. Ferroelectricity of AD film was found to be improved by adding low melting point auxiliary agents and using calcined powder, and was also found to depend on the grain size of injection powder, and to be improved by increasing the size to an appropriate value. By optimizing the conditions, good ferroelectricity was realized; such as Pr = 25.4 micro C/cm2 in the heat treatment at 600°C (63% of sintered film, calcined powder added with low melting point glass) and Pr = 38.0 micro C/cm2 in the heat treatment at 700°C (95% of sintered film, calcined powder added with Bi2O3-ZnO).

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Aerosol deposition, based on room temperature impact consolidation (RTIC), can form aluminum oxide films on some of the plastics. However the characteristics of these films are not yet known much. One of the important characteristics of ceramic films on plastics is to block liquid to protect the plastic substrates. This may also give information on the structures of aerosol deposited films on plastics. So blocking characteristic of aerosol deposited aluminum oxide films on polycarbonate plates was evaluated with liquid acetone. Polycarbonate becomes clouded when liquid acetone is poured on. Therefore the state of substrate polycarbonate can show whether the aluminum oxide films effectively blocked the liquid by pouring acetone on the films. The aerosol deposited thin aluminum oxide films could not block acetone, and the whole area covered by acetone becomes clouded. In thicker films the residual stress in the films cause many cracks initiated from attacked points by acetone and frequently aluminum oxide films were peeled off from polycarbonate substrates. When the thickness is over lO~m, the films could block acetone. This suggests the existence of minute pores in the aerosol deposited films on plastic substrates.

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In this study, nano-porous mullite nano-powders were prepared to deposit the low-K thin films on the LTCC by the direct material writing. For the first step, prepared nano-porous mullite nano-powders were spin-coated on a Si wafer with Pt electrode to investigate the electrical properties of the resulting nano-porous low K thin films. As a result, nano-porous thin films of mullite with enough high registivity were successfully deposited by the spin-coating using the highly nano-porous mullite nano-powder. The electrical properties of the resulting nano-porous thin films depended on the hybrid structure of the films, showing the possibility for the material direct writing by using the nano-porous mullite nano-powders for the low K thin films on a LTCC.

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The synthesis of novel aromatic diamine compounds containing phosphorylcholine (PC) group was carried out, which gave the high molecular weight polyamides with PC group by polycondensation. The obtained polymers exhibited the excellent biocompatibility, which would be due to the surface structure derived from PC side chain. In addition, the obtained polymers showed the high thermal stability up to 250°C, at which the thermal degradation of PC moiety occurred. Therefore, these polymers are expected as tough biocompatible materials for the use of biomedical devices.

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The syntheses of siloxane-grafted polyamides were carried out by a macromonomer method, in order to develop a highly permeable and durable membrane material for pervaporation. A novel compounds, 3,5-bis(4-aminophenoxy)benzyloxypropyl-terminated polydimethylsiloxane (BAPB-PDMS), and 3,5-bis(4-amino-3-methylphenoxy)benzyloxypropyl-terminated polydimethylsiloxane (BAMPB-PDMS), were synthesized as macromonomers, which consisted of different PDMS segment lengths. The polycondensation of BAPB-PDMSs or BAMPB-PDMSs with terephthaloyl chloride yielded the desired siloxane-grafted polyamide copolymers, PA-g-PDMS and MPA-g-PDMS, respectively. The copolymer membranes were prepared by solvent casting method, and the gas permeability and pervaporation property of these membranes were evaluated. PA-g-PDMS was insoluble in any solvents after the copolymer was dried in vacuo, however, MPA-g-PDMS was soluble in solvents, such as tetrahydrofuran, chloroform and dichloromethane. Therefore, MPA-g-PDMS exhibited the higher processability than PA-g-PDMS. The gas permeability coefficients of these copolymer membranes were increased as increase of PDMS segment length, and these values of MPA-g-PDMS were slightly higher than those of PA-g-PDMS containing the same PDMS segment length. From the results of pervaporations of the dilute aqueous solutions of organic solvents, it was found that both of PA-g-PDMS and MPA-g-PDMS exhibited the excellent permselectivity toward several organic solvents, such as alcohols, acetone, tetrahydrofuran, chloroform, dichloromethane and benzene with a high and stable permeation.

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The preparation of novel poly[2]catenanes by direct bonding of [2]catenanes was investigated. The monomeric catenanes were prepared by cycloamidation of 5-substituted N,N'-bis[(4-aminophenyl)methyl]isophthalamides (2) and sebacoyl chloride in highly dilute solutions. Polycondensation of dihydroxy[2]catenane (3b) and dicarboxy[2]catenane (3d) resulted in a product with a low degree of polymerization, and a considerable amount of cyclic dimer (7) was formed. The desired novel poly[2]catenane 8 was obtained by azide-alkyne 1,3-dipolar cycloaddition of diazido[2]catenane (3e) and diethynyl[2]catenane (3f). The number-average molecular weight of the poly[2]catenane was between 3 x 104 and 5 x 104.

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MgO-ZnO solid solutions with different chemical compositions were prepared by heating at 1200oC for 5h in air. By XRD, a single phase of MgO was observed above the molar ratio (MgO/ZnO) of 1.86, of which the lattice constant increased linearly. Diffraction peaks corresponding to ZnO when the ratio was 1.22 were detected in addition to diffraction peaks of MgO. No change in lattice constant of MgO was recognized at the ratio of 1.22. Antibacterial characteristics towards Staphylococcus aureus and Esherichia coli were examined in four solid solutions by colony count method. In the results, antibacterial activity of MgO-ZnO solid solution was found to enhance with decreasing the molar ratio in the range from 9.00 to 1.86. At the ratio of 1.22, however, the antibacterial activity reduced. That is, antibacterial activity of the MgO-ZnO solid solution was found to be dependent on the chemical composition.

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A novel method to synthesize a GaN crystal was studied by the reaction of Ga2O3 with Li3N in liquid Ga. We have already reported that the synthesis of GaN particles by a reaction of Ga2O3 with Li3N. However its particle sizes were limited to be smaller than several micrometer due to the solid-phase reaction. In order to grow bulk GaN single crystals, liquid Ga was used as a Ga source and a reaction bath. We have found that the GaN crystals with about 200 micro m size were synthesized under mild condition at the temperature ranging from 650°C to 800°C under N2 atmosphere.

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Formation of polystyrene layer on Si (111) surface from hydrogen-tenninated Si (111) was reported. Styrene was polymerized from RAFT (reversible addition-fi·agmentation chain transfer) agent immobilized Si (111) with AIBN and cumyl dithiobenzoate. The Si (111) chips obtained were estimated by water droplet contact angle, and XGT microscope. The contact angle was increased up to 101° by the change to hydrophobicity. Polystyrene layer was detached from Si (Ill) with hydrolysis and the polymer obtained was analyzed by GPC.

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Nickel(II) dithiocarbamates from glycine(1), beta-alanine(2), 4-aminobutyric acid(3) and 5-aminovaleric acid( 4) were synthesized successfully from their triethylammonium dithiocarabamate salts. Among them, complex 1 formed a linear polymer through a cumulative face-to-face hydrogen bonding between terminal carboxylic moieties. Complexes 2-4 showed similar broad absorption bands to 1 assignable to carboxylic moiety with hydrogen bonding. These broad absorption bands suggested the formation of linear polymers connected with such hydrogen bondings.

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A novel disilanol monomer, i.e. 1,6-bis(dimethylhydroxysilyl)pyrene (M1), was synthesized and underwent polycondensation to afford the corresponding poly(tetramethyl-1,6silpyrenylenesiloxane). The soluble parts in common organic solvents obtained by the polycondensation of Ml were expected to be the cyclic oligomers as deduced from the measurements of gel permeation chromatography as well as the NMR and IR spectroscopy. The insoluble parts in common organic solvents were expected to be the linear polymer with high molecular weight. Thus, the copolymer (CPl) was synthesized by the copolymerization of Ml and 1,4-bis(dimethylhydroxysilyl)benzene was carried out to afford the corresponding copolymer (CPl), which was soluble in common organic solvents, such as tetrahydrofuran, dichloromethane, chloroform, toluene, and so on. The results of the differential scanning calorimetry (DSC) and thermogravimetry (TG) indicated that CPl exhibited the crystallinity with relatively high thermal stability.

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To use as a soluble scavenger resin, polystyrene having triethylene glycol mmetles was prepared from copolymerization of 2-{2-[2-(4-vinylphenoxy)ethoxy]ethoxy}ethanol (2) with styrene (St). The terminal hydroxyl group of the obtained copolymer (3) was reacted with 4-hydroxybenzaldehyde to obtain the polystyrene ( 4) having formyl group. To functionalize 3 further, the terminal hydroxyl group was reacted with diketene to obtain the polystyrene (6) having beta-ketoester. Reactions of 4 and 6 with benzylamine were investigated to confirm their abilities for scavenger resin. The performances of those soluble polymers for scavengers were thoroughly investigated.

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Gamma'-Fe4N is the ferromagnetic material with high Curie temperature and relatively high electrical conductivity. First principle calculation showed that the ganma'-Fe4N was a half-metal by 100% spin polarized conduction electrons with minority spins. So we expected large tunneling magneto-resistance effect in the Fe4N/MgO/Fe4N junctions. Gamma'-Fe4N was prepared by sintering Fe3O4 nanoparticles in the atmosphere of NH3/H2 gas mixture at 673 K. Then MgO was added to the gamma'-Fe4N powder and sintered at about 473 K in pure Ar gas. Magneto-resistance was measured by 4-terminals method for x=0-0.8 samples of (MgO)x(Fe4N)1-x, and magneto-resistance ratios of -1.2~-1 % were observed for x=0.3~0.6 samples at 300K. It is the first observation oftunneling magneto-resistance effect for gamma'-Fe4N granular system.

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Electrochemical deposition method has some advantages over the conventional methods such as large area deposition at low temperature. ZnO thin films were prepared by this method with various electrolytic current in a range of 4.5 - 122 micro A/cm2 to evaluate the relation of growth rate to the surface morphology. All samples showed 0002 preferred orientation tendencies. Furthermore, it was confirmed that the shape and size of grains depends heavily on the electrolytic current. The ZnO films deposited with electrolytic current of 22 - 71 micro m/cm2 had especially large hexagonal grains with sharp liner edges and flat planes.

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In this study, the growth of magnetite (Fe3O4) thin films on GaAs(100) substrates by gas flow sputtering is investigated. The condition of substrate preheating before the growth of Fe3O4 affects the epitaxy of the Fe3O4 film to a great extent: an epitaxial film is obtained by substrate preheating in air, while polycrystalline films are obtained without substrate preheating and by substrate preheating in vacuo and in Ar. The formation of arsenic oxides may play a key role in the epitaxial growth. Reflection high-energy electron diffraction suggests that the epitaxial relationship is Fe3O4(100)//GaAs(100) and Fe3O4[001]//GaAs[011], and scanning electron microscopy shows that the film has a mosaic-like texture.

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SrS:Cu films were prepared by an electron beam deposition method to improve the emission properties of blue EL elements. SrS:Cu pellets were used as an evaporant of SrS:Cu films. The correlation between pellet-sintering condition and crystallinity of SrS:Cu films was investigated. As a result, it was found that the 2-hour pellet-sintering under 600°C was best to prepare superior SrS:Cu films. It was also found that the crystallinity of SrS:Cu films were greatly improved after 2-min rapid thermal annealing (RTA) process under 450°C.

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SrS:Cu films were prepared by an electron beam deposition method to improve the emission properties of blue EL elements. SrS:Cu pellets were used as an evaporant of SrS:Cu films. The correlation between sintering condition and PL properties of SrS:Cu films was investigated. As a result, it was found that an 1-hour sintering under 600oC was best to prepare superior SrS:Cu films, and the correlation between sintering condition and PL properties of SrS:Cu films was confirmed.

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Hyperbranched aromatic polyamides with carboxyl groups at the chain ends were synthesized by polycondensation of a few ABx (AB2, AB4, AB8) type monomers based on 5-(4-aminophenoxy)isophthalic acid, which consisted of different degree of branch (DB). Then, a fluoroalkyl group was introduced into the branch ends by a polymer reaction of the hyperbranched polyamide with 2-perfluorobutylethanol. In addition, the surface properties of the polymer films were investigated by XPS analysis and measurements of contact angle of water and diiodomethane. It was found that the surface properties were affected by the degree of branch, where the hyperbranched polymer having DB=0.72 containing fluoroalkyl group exhibited the very low surface free energy.

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Ba2Ti9O20 crystal lattice has a Hollandite-like structure, and this compound possesses high ionic conductivity because the Ti06 octahedra form tunnel-like arrangement around Ba ions. It is used as an electronic material in high frequency devices due to its ferroelectricity and small temperature coefficient. The synthesis of pure material is very difficult because even small deviations from the required stoichiometry result in the formation of impurity phases with close to Ba2Ti9O20 chemical composition. Typical synthesis method of Ba2Ti9O20 needs annealing at higher than 1523 K temperature to complete solid-state reaction and to produce this peculiar material with the uniform overall chemical composition. In this study we prepared the precursor for Ba2Ti9O20 by complex gellation method in which citratoperoxititanic acid tetranuclear complex [Ti4(C6H4O7)4(O2)4]8- was used as a Ti source. The homogeneous precursor was obtained by mixing the Ti complex, Ba(CH3COO)2, and H3BO3 (as a flux) in an aqueous solution. The precursor was heat-treated at 1273 K, which is 230 K lower than the temperature of conventional solid-state reaction method, and single phase Ba2Ti9O20 was obtained. Crystallite size of the prepared particles was less than 100 nm that is desirable for ferroelectric materials.

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Cathodic electrodepositon of CuSCN thin films on F-doped SnO2 (FTO) substrates has been investigated in aqueous mixed solution of copper perchlorate and lithium thiocyanate. Cathodic current arose around +0.5 V vs. Ag/ AgCl and reached a plateau below ca. +0.3 V in the mixed solution. Levich analysis of the plateau current confirmed limitation of CuSCN deposition by mass transport. The current was proportional almost symmetrically to the concentrations of Cu2+ and SCN-, suggesting that transport of their complex was responsible. Absorption spectrum of the mixed solutions indeed revealed an appearance of a new peak only when both Cu2+ and SCN- were present. Job plot for this peak elucidated formation of 1 to l complex. As the concentration of this active species could be determined from the absorption spectra, Levich analyses at different temperatures made it possible to determine the frequency factor (Do) of and the activation energy (Ea) for the diffusion of (Cu2+)(SCN-) complex as 3.24 x 10-2 cm2 s-1 and 20.1 kJ mol-1 , respectively.

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Copolymerization of N-isopropylacrylamide (NIPAM) with styrene (2 mol% in feed) was performed using AIBN as an initiator to give a linear copolymer (la) of low-molecular-weight (Mn = 9.0 x 103, Mw/Mn = 1.49). The content of styrene in la was estimated as 1.8 mol% from 1H NMR spectra. Cross-linked poly(N-isopropylacrylamide) (2) was prepared using divinylbenzene (DVB, 2 mol% in feed) as a cross-linker (Mn = 8.6 x 103, Mw/Mn = 1.74). Lower critical solution temperature (LCST) of la and 2 determined from the transmittance of their 0.35% aqueous solution were 28.9 and 27.0 °C, respectively. When 1.0% aqueous solution of la was heated over LCST, the solution turned cloudy without agglomeration. In contrast, 2 gave agglomerates with heating over LCST. The effect of hydrophobic interaction, cross-linking agent, and cross-linking degree on the agglomeration tendency of 2 was discussed.

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Herein, we report on fabrication of nickel nanocomposite on polyimide resin via a direct metallization process using nickel complexes as the nickel precursor. The process relies on synthesis of poly(amic acid) solutions containing nickel complex formed from 4,4'-biphthalic anhydride (BPDA)/2,2'-Bis[4-(4-aminophenoxy)phenyl]propane (BAPP) and formation of poly(amic acid) films containing nickel complex followed by chemical reduction. Nickel nanoparticles could be seen to form on the surface and into the precursor polyimide film. The thin nickel nanocomposite films could be used as precursors for copper clad on polyimide films; the copper clad on polyimide films were obtained by electroless nickel deposition and copper electrodeposition. The metal films were highly adhesive; the films readily pass the Scotch-tape test. These results suggest that the nanocomposite layer at the interfacial region acts as a glue between the deposited metal and polymer via a nanoscale interlocking effect.

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Manganese oxides have been studied as a cathode material in the Li secondary batteries. Preparation of LiMn2O4 thin films were tried with a sputtering method. This material is superior to other materials in the cost performance as well as non-toxicity. The crystal properties were improved after an annealing process. The preparation procedure is introduced through this study.

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This paper describes the effects of particle size and its distribution on size measurements by means of interactive force apparatus. The apparatus was proposed for particle size measurement in our research group. The advantage of this apparatus is that size measurement using the apparatus is a direct measurement, not depending on the concentration and optical transparency of the solution. Moreover, the measurement can be conducted in both the aqueous solution and organic solvent. Other common apparatuses for size measurements using laser source (i.e., the dynamic light scattering and laser diffraction) are difficult to measure the size of particles in the solution of high particle concentration and/or low transparency accurately, due to multi-scattering of light in the sample solution or solvent. However, the appropriate experimental conditions for particle size measurement using the interactive force apparatus have not been fully determined. In the present study, (a) appropriate particle size range and (b) particle size distribution were determined by calculating (a) the forces acting on fine particles and (b) the potential energies of a cluster under the electric field.

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The hydrogen adsorption properties and uptake capacities of three-dimensional (3-D) microporous materials of lantern-type dinuclear M(BDC)(DABCO)1/2 (M = Co(II), Cu(II), Zn(II), BDC 1,4-benzenedicarboxylate, DABCO 1,4-diazabicyclo[2.2.2]octane, Co(BDC)(DABCO)1/2 1, Cu(BDC)(DABCO)1/2 2, Zn(BDC)(DABCO)1/2 3) were investigated at different temperatures of 77 K and 87 K and pressures up to 0.1 MPa. The results from hydrogen adsorption experiments conducted at 77 K and 87 K show that all complexes have a relatively high hydrogen uptake. The isosteric heats of hydrogen adsorption data calculated based on the Clausius-Clapeyron equation are consistent with these observations, indicating strong adsorbent-adsorbate interactions. The results indicated that the hydrogen heats of adsorption were 5.9-6.5 kJ/mol, 6.3-7.9 kJ/mol, and 5.6-6.0 kJ/mol for 1, 2, and 3, respectively.

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The following three dinuclear rhodium(II) monocarboxylates were synthesized and their structures determined by single-crystal X-ray diffraction: Rh2(o-CH3C6H5CO)4 (complex 1), Rh2(m-CH3C6H5COO)4 (complex 2), Rh2(p-CH3C6H5COO)4 (complex 3). All complexes formed lantern-like structures. It was revealed that complex 1 does not consist of pi-pi stackings, but both complex 2 and complex 3 do consist of pi-pi stackings and are constructed from one-dimensional micropores when viewed from the direction of the b axis and c axis, respectively. In addition, two methanol molecules that are used as their solvents are linked to the axial sites of these complexes. The Rh-Rh distance in complex 1 was 0.2390 nm, that in complex 2 was 0.2379 nm, and that in complex 3 was 0.2388 nm.

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Indium-tin-oxide (tin-doped In2O3) thin films are indispensable for flat panel displays and solar cells. The ITO coated glass windows absorb near-infrared radiation from the Sun in summer and reflect far-infrared radiation from the interior in winter to reduce the energy consumption for cooling and heating, respectively. The ITO films are usually deposited by sputtering process which requires expensive vacuum system and ceramic targets whose sintering needs heating at high temperature. The authors reported elsewhere the inexpensive spray CVD (chemical vapor deposition) using ethanol solution of indium chloride and tin chloride. The solvent is replaced in the present study by water as a more environmentally-benign one for easier recycling of uncoated raw materials and the by-product of hydrogen chloride. The lowest resistivity was 9.7x10-5 ohm cm after the post-deposition annealing at 600°C in N2-0.1%H2 flow. This value was compatible with our previous report using ethanol solvent and the one deposited by sputtering process. An ITO film deposited with a less green solvent, 2-propanol at approximately is briefly demonstrated.

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Thin films of indium oxide (In2O3) doped with tin (indium-tin-oxide; ITO) are widely used as transparent conducting films for flat panel displays and solar cells etc. Only a few papers reported the sintered bodies and doping with other tetravalent ions. The relation between the colors and the resistivities were not examined systematically although the engineers have understood that dark blue sputtering targets were empirically preferable to light green ones. A color meter was used in the present study to examine quantitatively the correlation with the resistivity of the In20 3 sintering bodies doped with Ti4+, Sn4+, Hf'+ and Zr4+ whose resistivites (2.9x10-4, 8.5x10-4, 5.7x10-3, 4.3x10-3 and 3.0x10-2 ohm cm, respectively) were lower than that of pure indium oxide (4.8x10-2 ohm cm). The resistivites were approximately correlated with the color of the sintered bodies expressed by the coordinates in the chromaticity diagram.

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Indium-tin-oxide (tin-doped In2O3) thin films are widely used for flat panel displays and solar cells etc. The authors reported elsewhere low resistivity ITO films deposited by spray chemical vapor deposition using ethanol solution of indium chloride and tin (II) chloride. Indium is a rear element whose price is increasing as the results of mass production of flat panel displays. Recently the powders of indium oxide including ITO damage the human lungs. As an approach to fabricate environmentally-benign alternative transparent conducting materials, undoped tin oxide (SnO2) was deposited by the same process using ethanol solution of tin (II) chloride although the resistivity is much higher since doping with antimony or fluorine was avoided. The lowest resistivity of the as-deposited films was 6.2 x 10-3 ohm cm for the 138 nm-thick film deposited at 255°C. The resistivity increased at the higher temperature. Excellent step coverage was observed when deposited on silicon substrates with stripes (depth, 1 micron).

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In order to make clear the photodegradation mechanisms of the cyclic olefin polymers, hydrogenated poly (cyclohexadiene-ran-butadiene) (H-CHB) and hydrogenated polystyrene (H-PS), photo-irradiation experiment and analysis of the photodegradation products have been taken place. Under our experimental conditions, we concluded that the polymer degradation occurs similar to the degradation of general polyolefin. Photo-irradiation generates ester bonds, ether bonds, ketones, alcohols and end groups such as carbon-carbon double bonds, aldehydes and chain-end methyl. The photo-irradiation on these cyclic olefin polymers forms the gel mainly.

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Polyethylene oxide (PEO) has high hydrophilicity and high-crystallinity. Moreover, the crystallinity affect on the hydrophilicity of the PEO. In this study, PEO-H2O systems, which were given cyclic temperature change between 30 °C and 60 °C, were measured by high frequency spectroscopic method, which can detect the change of the solution structure and/or the boundary state of molecules sensitively. From the results, the temperature dependence of the resonance frequency showed deference with the water content and the molecular weight of the PEO. Water rich mixture, which was containing water with the ratio of EO : H2O= 1: 10, showed similar temperature dependency with water. On the other hand, low water content sample with the ratio of EO : H2O =1 : 1 showed a characteristic behavior suggesting the bound state change of water molecules caused by PEO melting. Same results were obtained from lower molecular weight PEO samples by perform the measurements at lower temperature range (15 °C~40 °C). These results suggest that bound state of water deeply relate on the crystallinity of PEO, and high frequency spectroscopy can detect these changes as resonance frequency shifts in the spectra.

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