• The Korean Journal of Ceramics
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• v.4 no.3
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• pp.231-234
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• 1998

LaNiO3 thin films were fabricated on various substrates by spin-coating technique using metal naphthenates as starting materials. Highly-oriented LaNiO3 films with smooth and crack-free surfaces were grown on SrTiO3 (100) and LaAlO3(100) substrates, while films on MgO(100) and Si(100) substrates showed random orientation. In this study, we concluded that lattice-mismatches between LaNiO3 films and substrates used affect film's properties.

• Journal of the Korean Ceramic Society
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• v.28 no.11
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• pp.859-864
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• 1991

High quality lead titanate thin films were fabricated by spin coating on a silicon substrate. The resulting dried gel layers were uniform in thickness through 2$\times$2 $\textrm{cm}^2$ area, and polycrystalline perovskite structures developed almost crack free with a heat treatment above 50$0^{\circ}C$ in films with thickness above 360 nm. Metastable pyrochlore structures were observed in films with thickness of 160 nm when heat treated at 500 and $600^{\circ}C$, but these structure did not appear in films with thickness of 360 nm. The thickness dependence in crystal structure of films was studied. by varying the substrate condition and analyzing the interface between the film and substrate. In native oxide films on silicon stbstrates, amorphous dried gel layers were heterogeneously nucleated. Metastable cubic pyrochlore structure could be crystallized in amorphous native oxide.

• Progress in Superconductivity
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• v.3 no.2
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• pp.188-192
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• 2002

To introduce flux pinning center in HTS-BSCCO system, nano-size MgO particles were uniformly distributed within the Bi-2223 grain by partial hydration of MgO. The existing method MgO doped Bi-2223 used nato-size MgO powders, which resulted in agglomeration during mixing or grain growth during heat-treatment due to the high surface energy of the fine particles. By hydration of the MgO surface, the agglomeration of the MgO powders was avoided and the size of remaining MgO core was controlled by changing hydration medium and time. The thin film obtained by spin coating of (Bi_$1.8/Pb_{0.4}$)$Sr_2$$_{Ca}$$2.2/Cu_3$ $O_{y}$ nitrate solution mixed with hydrated MgO showed the even distribution of nano-size MgO particles in the Bi-2212 grains.s.s.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.192-195
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• 2000

Antimony doped tin oxyde thin films have been deposited by sol-gel method using non-alkoxide precursor SnCl$_2$$.$2H$_2$O as host and SbC1$_3$ as dopant material. Using spin coating method, thin films of thickness up to 200nm have been uniformly deposited on Corning 1737F non-alkali glass substrates. Effect of Sb doping concentration and heat treatment on electrical and optical properties was investigated. Heat treatment was performed at the temperature from 350$^{\circ}C$ to 650$^{\circ}C$ in flowing O$_2$. The resulting ATO films showed widely changing electrical resistivity and optical transmittance values in the visible spectrum depending on the composition and firing condition.

• Korean Chemical Engineering Research
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• v.55 no.6
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• pp.754-761
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• 2017

UV-curable hydrophilic coating solutions were prepared by mixing colloidal silica dispersed in alcohol with an acrylic monomer, pentaerythritol triacrylate (PETA). Hydrophilic coating films were also prepared by spin coating the hydrophilic coating solutions on PC substrates and UV curing for 10 minutes subsequently. The effect of the amount of colloidal silica in the coating solutions, which was varied from 10 g to 50 g, was investigated on the hydrophilic properties of UV-cured coating films. The results showed that the amount of colloidal silica had a great influence on the hydrophilic properties of UV-cured coating films and the coating film prepared with 30 g of colloidal silica showed a lowest contact angle of $37^{\circ}$ and an excellent pencil hardness of H.

• Journal of the Korean Ceramic Society
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• v.30 no.9
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• pp.695-700
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• 1993

In this study, we prepared Pb-Ti stock solution by sol-gel processing and deposited PbTiO3 thin film on a Pt coated SiO2/Si wafer by spin coating using the stock solution. We used lead acetate trihydrate and titanium isopropoxide. The stock solution was partially hydrolized and finally a 0.25M coating solution was prepared. We achieved spin coating at 4000rpm for 30 seconds and heated the thin film at 375$^{\circ}C$ for 5 minutes and at $600^{\circ}C$ for 5 minutes successively, first and second heating state. And the thin film was finally sintered at 90$0^{\circ}C$ for 1 hour in the air. The upper electrode of the thin film was made by gold sputtering and was cricle shape with radius 0.4mm. Measured dielectric constant, dissipation factor and phase transition temperature(Cuire Temp.) were about 275, 0.02 and 521$^{\circ}C$ respectively. To observe ferroelectric characteristics we calculated Pr(remnant polarization) and Ec(coercive field) byhysteresis curve. Ec was 72kV/cm and Pr was 11.46$\mu$C/$\textrm{cm}^2$.

• Journal of the Korean Ceramic Society
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• v.48 no.6
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• pp.516-519
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• 2011

Indium tin oxide (ITO) coatings were made using an ITO slurry and an ITO sol. This was achieved by dispersing nanosized ITO powder in a mixed solvent without any dispersant and developing an adhesive ITO sol from indium acetate and tin tetrachloride in a mixture of DMF and n-butanol. Coating was carried out in one step by spin coating an ITO slurry, which was then followed by an ITO sol over it. Here, the sol penetrates into the nano ITO particle layers to make them adhere to each other as well as to a glass substrate. This is then followed by sintering at 500$^{\circ}C$ for 1 h to produce a uniform film consisting of ITO particles of about 50 nm and 10 nm. ITO films were obtained with sheet resistances from 450 to 1500 ohm/${\Box}$ by varying spin speed and concentration. Transmittance is higher than 90% at 550 nm.

• Proceedings of the Materials Research Society of Korea Conference
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• 1997.10a
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• pp.89-89
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• 1997

• Journal of the Microelectronics and Packaging Society
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• v.10 no.4
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• pp.35-38
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• 2003

Polymer light emitting diode (PLED) with an ITO/MEH-PPV/Al structure were prepared by spin coating method on the ITO (indium tin oxide)/glass substrates, using poly(2-methoxy-5-(2-ethylhexoxy)-1,4-phenylenevinylene (MEH-PPV) as the light emitting material. The dependence of heat treatment on the electrical and optical properties for the prepared PLED samples were investigated. The luminance decreased greatly from 630 cd/$\m^2$ to 280 cd/$\m^2$ at 10V input voltage as the heating temperature increased from $65^{\circ}C$ to $170^{\circ}C$. In addition, the luminance efficiency was found to be about 2 lm/W for the sample heat treated at $65^{\circ}C$. These results may be related to the interface roughness and/or the formation of an insulation layer, which is caused by the reaction between electrode and MEH-PPV organic luminescent film layer.

• Journal of the Semiconductor & Display Technology
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• v.14 no.1
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• pp.61-65
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• 2015

We have fabricated poly(3,4-ethylenedioxythiophene) : poly(4-styrenesulfonate) (PEDOT : PSS) thin films using a slotdie coater for the applications of OLED lightings. It is demonstrated that the properties of slot-die coated PEDOT : PSS films are comparable with those of spin-coated ones. Namely, the average and peak-to-peak roughness of the slot-die coated 50-nm-thick PEDOT : PSS film are measured to be as low as 0.247 nm and 1.3 nm, respectively. Moreover, we have obtained excellent thickness uniformity (~1.91%). With the slot-die coated PEDOT : PSS films, we have fabricated green phosphorescent OLED devices. For comparison, we have also fabricated OLED devices with spin-coated PEDOT : PSS films. Both show almost no discrepancy in device performance. The power efficiency (25.4 lm/W) and emission uniformity (77%) of OLEDs with slot-die coated PEDOT : PSS films are shown to be slightly lower than those (27.3 lm/W, 80%) of OLEDs with spin-coated PEDOT : PSS films at the luminance of 1,000nit, increasing the feasibility of using a slot-die coating process for the fabrication of large-area OLED lighting sources at a competitive price.