• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.777-782
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• 2008

Using ultrasonic-induced polymerization of pyrrole, mesoporous $TiO_2$ thin film with polypyrrole nanoparticles was prepared. Polypyrrole nanoparticles were ultrasonically synthesized in the mother solution of mesoporous $TiO_2$ before spin-coating. The polypyrrole particles were well dispersed in the solution. After spin-coating and calcinations process, the nanocomposite films have well-organized pore channels without pore-collapse, and polypyrrole nanoparticles are well dispersed in mesoporous $TiO_2$ matrix. The pore size and light absorbance of the mesoporous nanocomposite thin films were controlled by using different template materials, and by using different amount of pyrrole monomer, respectively.

• Journal of Sensor Science and Technology
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• v.31 no.4
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• pp.249-254
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• 2022

To achieve high-performance colloidal quantum dot light-emitting diodes (QD-LEDs), the use of a densely packed QD film is crucial to prevent the formation of leakage current pathways and increase in interface resistance. Spin coating is the most common method to deposit QDs; however, this method often produces pinholes that can act as short-circuit paths within devices. Since state-of-the-art QD-LEDs typically employ mono- or bi-layer QDs as an emissive layer because of their low conductivities, the use of a densely packed and pinhole-free QD film is essential. Herein, we introduce the Langmuir-Blodgett (LB) technique as a deposition method for the fabricate densely packed QD films in QD-LEDs. The LB technique successfully transfers a highly dense monolayer of QDs onto the substrate, and multilayer deposition is performed by repeating the transfer process. To validate the comparability of the LB technique with the standard QD-LED fabrication process, we fabricate and compare the performance of LB-based QD-LEDs to that of the spin-coating-based device. Owing to the non-destructiveness of the LB technique, the electroluminescence efficiency of the LB-based QD-LEDs is similar to that of the standard spin coating-based device. Thus, the LB technique is promising for use in optoelectronic applications.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.1147-1150
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• 2003

When a braun tube becomes wider, one of the major problems to be experienced is the non-uniform coating along the four diagonal directions on its surface. This non-uniformity in the coating thickness has a deep relation with the fluid flow on the surface of a braun tube. In order to control the fluid flow properly, we install the plate to block fluid flow at the corner of a braun tube. In the present study, we investigate the effects of the geometry of plate to control the fluid flow and coating uniformity and determine the optimal shape of plate to improve the quality of coating uniformity.

• Journal of the Korean Ceramic Society
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• v.29 no.3
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• pp.216-222
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• 1992

PLZT thin films were prepared using sol-gel spin coating. The films mainly consisted of perovskite phase when heat treated at 600$^{\circ}C$ and in O2 or air atmosphere for 2 hours after 7 coating cycles. Cracks were formed when smaller than after 9 coating cycles. When ITO interlayer existed between Corning 7059 glass substrate and the film, cracks were not formed after 9 coating cycles, but cracks were formed after 11 coating cycles because of large volume change of the film contracting on the substrate during the heat treatment. In the observation of microstructure, the thin films have perovskite phase of about 2 $\mu\textrm{m}$ grain size and pyrochlore phase of 100∼200${\AA}$ grain size.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.360-360
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• 2011

We demonstrated the fabrication method of superhydrophobic nanocoating through a facile spin-coating and the chemical modification. The resulting coating showed a tremendous water repellency with a static water contact angle (CA) of 158$^{\circ}$ and a hysteresis of 1$^{\circ}$. The number of ZnO nanoparticle (NP) coating cycles affected on the surface roughness, which is key role for superhydrophobic surface, and thus the CA can be modulated by changing the ZnO NP coating cycles. The CA can be controlled by changing the carbon length of Self-Assembled Monolayers(SAM). This simple ZnO coating is substrate-independent including flexible surfaces, papers and cotton fabrics, which can effectively be used in various potential applications. We also observed the thermal and dynamic stabilities of SAM on ZnO nanoparticles. The superhydrophobicic surface maintained its superhydrophobic properties below 250$^{\circ}C$ and under dynamic conditions.

• Journal of the Korean Graphic Arts Communication Society
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• v.9 no.1
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• pp.27-44
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• 1991

In this research, double-layered photoconductor consist of the carrier generation layer(CGL) of ${\varepsilon}$ type copper phthalocyanine thin film by an aqueous coating method and the carrier transport layer(CGL) of polyvinyl carbazol(PVK) by spin coating. We inverstigated effect of the surfactant solution and cathod electrolysis to the crystal type of ${\varepsilon}$-CuPc in CGL with TEM, SEM and X-ray diffraction spectroscopy and studied the mechanism of an aqueous coating for the preparation of CGL. The effect of the washing of CGL about the electrophotographic characteristics of the ${\varepsilon}$-CUPC/PVK double-layered photoconductors is studied also.

• Applied Chemistry for Engineering
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• v.17 no.6
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• pp.580-585
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• 2006

UV-thermal dually curable coating materials were prepared by the sol-gel method. Nano-sized colloidal boehmite was treated with various organo silane coupling agents. These materials could be well dispersed in various alcohols and relatively polar organic solvents such as tetrahydrofuran and acetonitrile. The coating films were prepared by a spin coating method on various substrates, which were characterized by FT-IR, Si/Al CP MAS NMR spectra, UV-Vis spectrophotometer, FE-SEM, Taber abraser, haze meter, and pencil hardness tester. The effects of molar ratio and types of silane coupling agents, curing method and ion-shower treatment were investigated. Dually curable coating method offered an optimally good quality film in both hardness and transmittance. The transparency and the hardness of the prepared films were increased with amounts of 3-(trimethoxysilyl)propylmethacrylate, and (3-glycidyloxypropyl)trimethoxysilane, respectively. The adhesion between coated layer and substrate could be enhanced by ion-shower treatment.

• New Physics: Sae Mulli
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• v.68 no.11
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• pp.1208-1214
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• 2018

The one-step spin coating method is reported as an excellent thin film process because it can be easily used to fabricate high-quality methyl-ammonium lead tri-iodide ($MAPbI_3$) perovskite layers. One of the important things in the one-step spin coating method towards obtaining high-quality $MAPbI_3$ layers is the anti-solvent (AS) engineering, which consists of an one-step deposition of the $MAPbI_3$ film and dripping of the AS. The properties of the $MAPbI_3$ layer were found to be strongly influenced by the amount, dispensing speed, and spraying time of the AS solution. The $MAPbI_3$ solution was prepared by dissolving lead iodide and methyl-ammonium iodide in N,N-dimethylformamide and adding N,N-dimethyl sulfoxide. Diethyl ether (DE) was used for the AS solution. The results indicate that a $MAPbI_3$ layer appropriately sprayed with DE is beneficial for improving film quality and device efficiency because nucleation of $MAPbI_3$ layer is affected by the characteristics of DE, which affect the film's crystallinity, density, and surface morphology. The $MAPbI_3$ layer, which was optimized by using 0.7 mL of DE, a 3.03 mL/sec dispensing speed, and a 7 second time to spray after spinning showed the best efficiency of 13.74%, which was reproducible.

• Journal of Korean Ophthalmic Optics Society
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• v.4 no.1
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• pp.51-56
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• 1999

$TiO_2$ thin films were spin coated on commercial Nickel-Silver with 2%Ti-naphthanate toluene solution by sol-gel process. The thin films were heat-treated at $500^{\circ}C$ for 2min and then decorative-protective coating was obtained. The conditions for gold colored coating, and the morphology, microstructure and color of the coating surface were have been characterized by Optical microscope, Photospectrometer and XRD. The heating temperature of colored-$TiO_2$ coating was $500^{\circ}C$ and was preferable. The average thickness of 1 time coating was $0.24{\mu}m$ and the total thickness increased linearly as a function of the coating time. The color of amorphous colored-$TiO_2$ coating was changed from gold to dark redish gold with coating time. 'L' as lightness and 'b' were decreased to red, but 'a' was decreased to blue after increase with coating time.

• Journal of the Korean Chemical Society
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• v.50 no.3
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• pp.243-246
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• 2006

The LiCoO2 thin films were prepared on the Pt/Ti/SiO2/Si substrate by spin coating using citrate sol. The citrate sol was spin-coated on substrate and dried at 380oC for 15 min. to evaporate the solvents and remove the organic materials. The as-deposited films were annealed at 750oC for 10 min. in air for crystallization. The X-ray diffraction patterns for the film have been indexed hexagonal system with space group R3m. The active area of LiCoO2 films for electrochemical test was about 11cm2. A Li foil and 1M LiClO4 in propylene carbonate(PC) and ethylene carbonate(EC) (1:1)were used as an anode and an electrolyte, respectively. The galvanostatic charge-discharge test was carried out at constant current density ranging from 5 A/cm2 in the voltage window between 4.2 and 3.0 V. The first discharge capacity of the film is 0.35Ah/cm2-m. The cycling behavior of the LiCoO2 film is also reported.