• Journal of Adhesion and Interface
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• v.20 no.4
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• pp.146-154
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• 2019

In this study, alkoxysilane-functionalized amphiphilic polymer (AFAP), which have hydrophilic segment and hydrophobic segment functionalized by alkoxysilane group at the same backbone, was synthesized and used as a dispersant and control agent for reaction rate in the preparation of colloidally stable organic-inorganic (O-I) hybrid sols. After reaction with fluorosilane compounds, fluorinated O-I hybrid sols were prepared and coated onto glass substrate to form hydrophobic O-I hybrid coating films through low-temperature curing process. Surface hardness and hydrophobicity of cured coating films were varied with type of solvent and composition of AFAP and fluorinated alkoxysilane compounds. At appropriate solvent and composition of fluorinated alkoxysilane compounds, O-I hybrid coating film having high transparency and surface hardness could be prepared, which could be applicable to cover window of solar cell and displays.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.5 s.347
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• pp.11-16
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• 2006

This paper reports the correlation between dielectric constant and degree of amorphism of the hybrid type SiOC thin films. SiOC thin films were deposited by high density plasma chemical vapor deposition using bistrimethyl- silylmethane(BTMSM,$H_{9}C_{3}-Si-CH_{2}-Si-C_{3}H_{9}$) and oxygen precursors with various flow rate ratio. As-deposited film and annealed films at $400^{\circ}C$ were analyzed by XRD. The SiOC thin films were amorphous from XRD patterns. For quantitative analysis, the diffraction pattern of the samples was transformed to radial distribution function by Fourier analysis, and then compared with each other. The degree of amorphism of annealed films was higher than that of as-deposited ones. The dielectric constant varied in accordance with flow rate ratio of precursors. The lowest dielectric constant was obtained from the as-deposited film which has the highest degree of amorphism after annealing.

• Polymer(Korea)
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• v.37 no.2
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• pp.127-134
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• 2013

The vascular endothelial cells are the inner layers of blood vessels. It regulates the function of blood vessels and proliferation of vascular smooth muscle cells. Poly(lactide-co-glycolic acid) (PLGA) is a biodegradable synthetic polymer with a well-controlled degradation rate and an acceptable mechanical strength. It can be easily fabricated into many shapes. Silk consists of 18 amino acids. It found important for attaching cells cultured in vitro, and maintaining cell functions. In this study, we fabricated silk/PLGA biomaterial hybrid films of 0, 10, 20, 40 and 80 wt% silk. We performed MTT, SEM, ELISA, and immunocytochemistry analyses. We confirmed the adhesion and the proliferation of HAECs on silk/PLGA according to the content of silk, and 40 wt% silk/PLGA hybrid films have superior adhesion and proliferation properties. These results demonstrate that silk/PLGA hybrid films provide suitable surfaces for HAECs, and there is the effect of silk on cell growth and proliferation.

• Progress in Superconductivity and Cryogenics
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• v.17 no.2
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• pp.1-17
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• 2015

$MgB_2$ thin films with superior superconducting properties are very promising for superconducting magnets, electronic devices and coated conductor electric power applications. A clear understanding of flux pinning mechanism in $MgB_2$ films could be a big aid in improving the performance of $MgB_2$ by the enhancement of $J_c$. The fabrication advancement and the understanding of flux pinning mechanism of $MgB_2$ thin and thick films fabricated by using hybrid physical-chemical vapor deposition (HPCVD) are reviewed. The distinct kind of $MgB_2$ films, such as single-crystal like $MgB_2$ thin films, $MgB_2$ epitaxial columnar thick films, and a-axis-oriented $MgB_2$ films are included for flux pinning mechanism investigation. Various attempts made by researchers to improve further the flux pinning property and $J_c$ performance by means of doping in $MgB_2$ thin films by using HPCVD are also summarized.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.289-289
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• 2011

The conducting polymer thin films were deposited using the gas phase method which known as molecular layer deposition (MLD). Terephthalaldehyde (TPA) and p-phenylenediamine (PD) were used as monomers to deposit conducting polymer. Self-terminating nature of TPA and PD reaction were demonstrated by growth rate saturation versus precursors dosing time. Infrared spectroscopic and X-ray photoelectron spectroscopy were employed to determine the chemical composition and state of conducting polymer thin films. Layer by layer growth and polymerization of thin films can be showed by shifting of absorption edge using UV-VIS spectroscopy. This conducting polymer fabricated by using MLD method gives the opportunity to develop new hybrid materials by combining inorganic materials in nanoscale.

• Macromolecular Research
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• v.17 no.9
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• pp.697-702
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• 2009

Mesoporous ethanesilica thin film was prepared using PEO-PLGA-PEO triblock copolymers as structure-directing agents and (1,2-bis(triethoxysilyl) ethane BTESE; bridged organosilicates) as inorganic precursors via one-step sol-gel condensation of ethanesilica precursors. The mesostructure of ethanesilica films is critically dependent on the processing experimental parameters after the hydrolyzed silica sol mixture was spin-cast. This study examined the effects of the block copolymer template/organosilica precursor ratio in the casting solution and aging period before calcination of the mesostructure. It was further demonstrated that mesoscopic ordering of organosilicate thin films is induced by the rearrangement of block copolymer template/organosilica hybrid during thermal decomposition of the PEO-PLGA-PEO triblock copolymer. The mesoporous structure and morphology were characterized by SAXS, TEM and solid-state NMR measurement.

• Korean Journal of Optics and Photonics
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• v.11 no.4
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• pp.255-260
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• 2000

We report that the crack-free organic-inorganic hybrid silica thin films were fabricated by sol-gel process using organometallic compounds as a precursor and that we have established very reproducible fabrication condition with systematic investigation of thickness and refractive index variations for various control parameters, such as, coating type, coating speed, chemical composition, prebake and postbake temperature. Additionally, we measured and compared the change of optical property with the UV exposure dose for three different kinds of photoinitiators. Furthermore, the fabrication of Ix4 MMI optical power splitter using the sol-gel thin film provides the possibility of various applications to the optical waveguide devices. vices.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.196-196
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• 2010

In this work, we deposited SWNTs/silane hybrid thin films by multiple spray-coating on glass substrate, and examined their electrical response for humidity. Generally silane binders which are often used in CNT solution to adhere CNTs to substrate well can be easily functionalized to each own group on the surface of CNTs after they are hardened by way of the hydrolysis reaction. We investigated how silane binders (TEOS,, MTMS and VTMS) in SWNTs hybrid thin films make effect to their electrical response on humidity. As the result, we observed that the resistance in the sample using TEOS was changed dramatically while it was almost invariant in the samples using MTMS and VTMS for increasing humidity.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1459-1461
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• 2009

In this study, we prepared the multi-refraction film thin by ink-jet technique with sol-gel precursor. The precursors were prepared by using some transition metal alk-oxide and the tetraethylorthosilicate (TEOS) mixed separately with n-Butyl Alcohol and PVB (Poly(vinyl butyral)).The structure and morphology of the resulting films were investigated by atomic force microscope (AFM). It is shown that the shape of the pattern of the films would affect the refraction proportion.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.2
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• pp.62-66
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• 2006

We investigated the characteristics of the hybrid-type superconducting fault current limiter (SFCL) by the number of secondary windings. The SFCL consists of a transformer, which has a primary winding and several secondary windings with serially connected $YB_{a2}Cu_{3}O_{7}$ films. In order to increase the capacity. of the SFCL, the serial connection between each current limiting unit is necessary. Resistive-type SFCL has a difficulty in quenching simultaneously between the units due to slight differences of their critical current densities. The hybrid-type SFCL could achieve the simultaneous quenching through the electrical isolation and the mutual flux linkage among the units. We confirmed that the capacity of the SFCL could be increased effectively through the simultaneous quenching among the units. In addition, the power burden of the system could be reduced by adjusting the number of secondary windings. We will investigate the method to increase the capacity through serial and Parallel connections among current limiting units.