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11.
Sul Lee Sunho Jeong Dongjo Kim Bong Kyun Park Jooho Moon 《Superlattices and Microstructures》2007,42(1-6):361
We have fabricated a solution-processed ZnO thin-film transistor without vacuum deposition. ZnO nanoparticles were prepared by the polyol method from zinc acetate, polyvinyl pyrrolidone, and diethyleneglycol. The solution-processable semiconductor ink was prepared by dispersing the synthesized ZnO in a solvent. Inverted stagger type thin-film transistors were fabricated by spin casting the ZnO ink on the heavily doped Si wafer with 200 nm thick SiO2, followed by evaporation of Cr/Au source and drain electrodes. After the drying and heat treatment at 600 C, a relatively dense ZnO film was obtained. The film characteristics were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). In order to obtain the electrical properties of the solution-derived transistor, the on–off ratio, threshold voltage, and mobility were measured. 相似文献
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Jinho Park Beomsu Jang Yu Ji Moon Hakjun Lee 《Molecular Crystals and Liquid Crystals》2020,705(1):120-126
AbstractIn this study, as the ongoing effort to develop efficient blue OLEDs, two deep blue emitters based on indenoquinoline-substituted anthracene derivatives have been synthesized and characterized. Multilayer organic light emitting diodes were fabricated with the following sequence: indium-tin-oxide (ITO)/4,4’,4’’-tris[2-naphthyl(phenyl)amino (2-TNATA)/4,4’-bis(N-(1-naphthyl)-N-phenylamino) biphenyl (NPB)/Blue emitting materials/Bathophenanthroline (Bphen)/lithium quinolate (Liq)/Al. All the devices showed efficient blue emissions. Particularly, a device using ‘2,7,7,13,13-pentamethyl-9-(10-phenylanthracen-9-yl)?7,13-dihydrobenzo[5,6]-s-indaceno[1,2-g] quinoline’ as an emitter showed a maximum external quantum efficiency (EQE) of 4.92% with the Commission Internationale De L’Énclairage (CIE) coordinates of (0.15, 0.10) at 8.0?V. 相似文献
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Gitae Moon Intae Son Chunho Kim Chi Hyeong Cho Eunbi Lee Eun Hyoung Bae 《Molecular Crystals and Liquid Crystals》2019,687(1):60-67
AbstractTo enable recent 3D and moving picture applications, liquid crystal displays (LCD) must exhibit fast response and wide viewing angle characteristics. Pre-tilted vertical alignment layers for high-speed LCD were fabricated using bi-functional photoreactive monomers. The monomers can be confined to the polyimide layer and photo-polymerized by UV exposure under voltage. Response characteristics of photo-controlled alignment films according to the structure were investigated. Vertical alignment properties were evaluated using a polarizing optical microscope, and electro-optical characteristics were compared through the voltage-transmittance curve and response time measurement. Faster response speed could be obtained by using photoreactive monomers having a long alkyl chain. 相似文献
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Park BK Jeong S Kim D Moon J Lim S Kim JS 《Journal of colloid and interface science》2007,311(2):417-424
We describe herein the synthesis of metallic copper nanoparticles in the presence of poly(vinylpyrrolidone), employed as a protecting agent, via a polyol method in ambient atmosphere. The obtained copper particles were confirmed by XRD to be crystalline copper with a face-centered cubic (fcc) structure. We observed monodisperse spherical copper nanoparticles with a diameter range 45+/-8 nm. The particle size and its distribution are controlled by varying the synthesis parameters such as the reducing agent concentration, reaction temperature, and precursor injection rate. The precursor injection rate plays an important role in controlling the size of the copper nanoparticles. On the basis of XPS and HRTEM results, we demonstrate that the surface of the copper is surrounded by amorphous CuO and that poly(vinylpyrrolidone) is chemisorbed on the copper surface. 相似文献
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Al2O3 incorporated HfO2 films grown by atomic layer deposition (ALD) were investigated by high-resolution X-ray photoelectron spectroscopy (HRXPS). The core level energy state of a 15 Å thick film showed a shift to higher binding energy, as the result of a silicate formation and Al2O3 incorporation. The incorporation of Al2O3 into the HfO2 film had no effect on silicate formation at the interface between the film and Si, while the ionic bonding characteristics and hybridization effects were enhanced compared to a pure HfO2 film. The dissociation of the film in an ultrahigh vacuum (UHV) is effectively suppressed compared to a pure HfO2 film, indicating an enhanced thermal stability of Hf-Al-O. Any dissociated Al2O3 on the film surface was completely removed into the vacuum by vacuum annealing treatment over 850 °C, while HfO2 contributed to Hf silicide formation on the film surface. 相似文献
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We propose the parameters of the Stillinger-Weber potential for hexagonal boron nitride (BN) structures. For the reliability of these parameters, the structural property of BN fullerenes is investigated. The stability of BN fullerenes increases with increasing the number of atoms, due to the reduction of the curvature effect of BN fullerenes. The structures of the relative stable fullerenes are B16N16, B18N18, B22N22, B25N25, and B28N28. 相似文献
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Jungwoo Moon 《Applied Surface Science》2007,253(18):7554-7558
The adsorption of metal ions, a type of surface reaction on binary mixed self-assembled monolayers (SAMs) on a gold surface composed of 1,6-hexanedithiol (HDT) with 11-mercaptoundecanoic acid (MUA), was monitored by in situ surface plasmon resonance (SPR) measurements. The differential SPR reflectance (ΔR) enables the kinetics of adsorption of Pt2+ on the mixed SAMs to be investigated. Unlike single HDT SAM, kinetic analyses of the mixed SAMs showed that the rate of adsorption of Pt2+ was enhanced and that it was highly dependent on the fraction of MUA present. These SPR measurements suggest that the adsorption rate of metal ions can be readily manipulated simply by using mixed SAMs. 相似文献