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The development of ferroelectric memory devices requires an improvement of the fatigue properties of ferroelectric thin films. Pb(Zr,Ti)O3(PZT) thin films obtained by the sol-gel method on Pt/Ti electrodes have reduced residual polarization by continuous polarization reverses about of 108 cycles. The electric characteristics such as fatigue properties have mostly depended on electrode materials. We propose Ir, IrO2, and these layer films as electrode materials and evaluate electric characteristics of PZT thin film capacitors. PZT thin films using Ir/IrO2 and Pt/IrO2 electrodes show no fatigue up to 1012 cycles of ±5 V switching pulses. Moreover, good properties of PZT capacitors, not only on SiO2 but also on polycrystalline silicon, were obtained by using IrO2.

We present a simple dry process to create nanoscale arrangements of metal nanoparticles within block copolymer films. This process involves only one step such that the vapor of palladium(II) acetylacetonato (Pd(acac)2) is exposed to a polymer film in a nitrogen atmosphere at 180 °C for periods up to 2 h. The Pd(acac)2 vapor penetrates into the film and then is decomposed and reduced to a metallic state to form nanoparticles therein. When block copolymer films having nanoscale microdomain structures are used, the metal complex is selectively reduced in one of the phases to give nanoscale arrangements of the metal particles that reflect the microdomain structure of the used block copolymer. In symmetric diblock copolymers of poly(styrene)-block-poly(methyl methacrylate) (PS-b-PMMA), Pd(acac)2 is selectively reduced in the PS lamellae to yield Pd nanoparticles with the average diameter ranging from 3 to 4 nm with a narrow size distribution, depending on the molecular weight. As a result, the Pd nanoparticles are arranged in a periodic lamellar manner within the film. In an asymmetric diblock copolymer having an alcohol group in the side chain of one of the blocks, poly(styrene)-block-poly(hydroxylated polyisoprene) (PS-b-PIOH), where the PIOH block forms spherical domains in the PS matrix, the Pd particles are selectively assembled in the PIOH domains, not in the PS phase. This approach would be of general applicability to any block copolymers, and the particles should be assembled in the phase having relatively stronger reducing power. The vapor of the metal complex can penetrate into the film deeply, and thus the arrangements of the particles are in a three-dimensional array within a film. Co(acac)2 is also evaluated and gives Co nanoparticles within the PIOH domains in the PS-b-PIOH film as does as Pd(acac)2. Electron spectroscopic imaging and electron energy loss spectroscopy on an energy-filtering transmission electron microscope were performed for nanoscale chemical analysis to investigate the reaction products of Co(acac)2 within the polymer films in detail.

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A colloidal rhodium has been prepared by reduction of rhodium(III) chloride with methanol in the presence of polyvinyl alcohol. The particle size distribution of the metallic rhodium is narrow ranging from 30 to 70 Å with a maximum at 35 Å. The colloidal dispersions in methanol-water solutions are effective for the hydrogenation of olefins at 30°C under an atmospheric hydrogen pressure.