• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.73-73
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• 1999

A large area negative metal ion beam source is developed. Kinetic ion beam of the incident metal ions yields a whole nucleation and growth phenomena compared to the conventional thin film deposition processes. At the initial deposition step one can engineer the surface and interface by tuning the energy of the incident metal ion beams. Smoothness and shallow implantation can be tailored according to the desired application process. Surface chemistry and nucleation process is also controlled by the energy of the direct metal ion beams. Each individual metal ion beams with specific energy undergoes super-thermodynamic reactions and nucleation. degree of formation of tetrahedral Sp3 carbon films and beta-carbon nitride directly depends on the energy of the ion beams. Grain size and formation of polycrystalline Si, at temperatures lower than 500deg. C is obtained and controlled by the energy of the incident Si-ion beams. The large area metal ion source combines the advantages of those magnetron sputter and SKIONs prior cesium activated metal ion source. The ion beam source produces uniform amorphous diamond films over 6 diameter. The films are now investigated for applications such as field emission display emitter materials, protective coatings for computer hard disk and head, and other protective optical coatings. The performance of the ion beam source and recent applications will be presented.

• Journal of the Korean Society of Clothing and Textiles
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• v.12 no.2 s.27
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• pp.207-216
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• 1988

This study is to examine the cleaningproof by dry cleaning runs and parts(shoulder, belly, butt) of garment leathers tanned chrome. This study is composed of three methods of test; color difference test, surface view by scanning electron micrographs, mechanical properties measurement by KES-FB system. The results obtained were as follows: 1. In stiffening of parts of sample, the belly is the best degree in smoothness, fullness, softness. But that of the butt have been found to be the worst degree and to be thick. 2. In fading of parts, the shoulder is an extreme case, but the belly is the best among three parts. 3. In dry cleaning runs, the view after 3 runs has been found to be the best result. 4. The stiffening after dry cleaning 1 run have been low grade, for the sample absorb much solvent of dry cleaning. And, the fading and the decoloration are to be worse after 5 runs. Because the leather surface is affected by dry cleaning runs.

• Textile Coloration and Finishing
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• v.6 no.3
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• pp.15-26
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• 1994

Cotton fabrics were treated with the cellulase which is an enzyme to decompose cellulose and its actional mechanism is known. The optimum condition of the cellulase to the cotton fabrics and the weight losses, tensile strengths of the treated cotton fabrics were also obtained. The cellulase performs a specific catalytic action on the ${\beta}-1$, 4-glucosidic bonds of the cellulose molecules and hydrolyzes them. For that reason, the negative surface charges of the cotton fabrics were increased by additional generation. of hyrdoxyl groups. The increased surface charges cause the decrease of dye adsorption by inhibiting the approach of the anions of direct dyes. But, it was overcome by the use of enough amount of salt, it means that sodium ions of the salt neutralize the almost all of negative charges of the cotton fabrics. The improvement of the water absorbency is also due to the increased hydroxyl groups In addition, their handles including the mechanical properties were measured and caculated by KES system which is a measuring apparatus that numerizes and objectificates human's feeling, especially touch. As the results, we knew that KOSH(stiffness) and FUKURAMI(fulness & softness) were decreased and that NUMERI(smoothness) was increased.

• Korean Journal of Materials Research
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• v.32 no.5
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• pp.249-257
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• 2022

Transparent thin films of pure and nickel-doped ZrO₂ are grown successfully by sol-gel dip-coating technique. The structural and optical properties according to the different annealing temperatures (300 ℃, 400 ℃ and 500 ℃) are investigated. Analysis of crystallographic properties through X-ray diffraction pattern reveals an increase in crystallite size due to increase in crystallinity with temperature. All fabricated thin films are highly-oriented along (101) planes, which enhances the increase in nickel doping. Scanning electron microscopy and energy dispersive spectroscopy are employed to confirm the homogeneity in surface morphology as well as the doping configuration of films. The extinction coefficient is found to be on the order of 10^-2, showing the surface smoothness of deposited thin films. UV-visible spectroscopy reveals a decrease in the optical band gap with the increase in annealing temperature due to the increase in crystallite size. The variation in Urbach energy and defect density with doping and the change in annealing temperature are also studied.

• Journal of Chitin and Chitosan
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• v.23 no.4
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• pp.256-261
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• 2018

Recently, the number of cardiovascular disease-related deaths worldwide has increased. Therefore, the importance of percutaneous cardiovascular intervention and drug-eluting stents (DES) has been highlighted. Despite the great clinical success of DES, the re-endothelialization at the site of stent implantation is retarded owing to the anti-proliferative effect from the coated drug, resulting in late thrombosis or very late restenosis. In order to solve this problem, studies have been actively carried out to excavate new drugs that promote rapid re-endothelialization. In this study, we introduced hydrophilic drug, tauroursodeoxycholate (TUDCA), that improves the proliferation of endothelial progenitor cells and promotes apoptosis of vascular smooth muscle cells. In addition, we utilized shellac, which is a natural resin from lac bug to coat TUDCA on the surface of the metal. When using conventional coating method including biodegradable polymers and organic solvents, phase separation between polymer and drug occurred in the coating layer that caused incomplete incorporation of drug into the polymer layer. However, when using shellac as a coating polymer, no phase separation was observed and drug was fully covered with the polymer matrix. In addition, by adjusting the composition of coating solution and modifying the hydrophilicity of the metal surface using oxygen plasma, the surface roughness decreased due to the increased affinity between coating solution and metal surface. This result provides a method of depositing a hydrophilic drug layer on the stent.

• Conservation Science in Museum
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• v.16
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• pp.82-95
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• 2015

Old Monk by Yun Duseo is realized to use silver paper which is made of rarity material. This sudy investigates reason why silver, that is easily discoloration in environmental condition, is susceptible in present. The method was the surface treatment materials and the base fiber through direct observation, optical instruments and XRF analysis. Based on these results, reproducing experiment was conducted to research materials in paper of Old Monk and the surface treatment technique. The results, the paper was treated 'Dochim' with a mineral having polygonal crystals for improving smoothness and density. XRF analysis result showed high calcium content, therefore, the paper was not used silver, it guess pulverized shells of abalone or other types of shellfish. Accordingly, the research was narrowed down to shells with shiny, reflective surfaces which at the same time contain high amounts of calcium. A new experiment was conducted using unprocessed abalone shells. Through the reproducing experiment, shellfish has high possibility as used mineral in paper. Notwithstanding, this experiment was unable to precisely reproduce the smoothness and shine of the original paper. Further research may therefore be needed.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.8
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• pp.8-14
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• 1997

RuO$_{2}$ thin films are prepared by RF magnetron reactive sputtering and their characteristics of crystallization, microstructue, surface roughness and resistivity are studied with various O$_{2}$/(Ar+O$_{2}$) ratios and substrate temperatures. As O$_{2}$/(Ar+O$_{2}$) ratio decreas and substrate temperature increases, the preferred growing plane of RuO$_{2}$ thin films are changed from (110) to (101) plane. With increase of the O$_{2}$/(Ar+O$_{2}$) ratio from 20% to 50%, the surface roughness and the resistivity of RuO$_{2}$ thin films increase form 2.38nm to 7.81 nm, and from 103.6.mu..ohm.-cm to 227.mu..ohm.-cm, resepctively, but the deposition rate decreases from 47 nm/min to 17nm/min. On the other hand, as the substrate temperature increases form room temperature to 500.deg. C, resistivity decreases from 210.5.mu..ohm.-cm to 93.7.mu..ohm.-cm. RuO$_{2}$ thin film deposited at 300.deg. C shows a execellent surface roughness of 2.38nm. As the annealing temperature increases in the range between 400.deg. C and 650.deg. C, the resistivity decreases because of th improvement of crystallinity. We find that RuO$_{2}$ thin film deposited at 20% of O$_{2}$/(Ar+O$_{2}$) ratio and 300.deg. C of substrate temperature shows execellent combination of surface smoothness and low resistrivity so that it is well qualified for bottom electrodes for ferroelectric thin films.

• The Journal of Korean Academy of Prosthodontics
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• v.36 no.3
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• pp.506-513
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• 1998

This study was designed to compare the smoothness by glazing method with that by polishing method after 48 specimens of Ceramco II block, one of porcelain materials used for PFM, were baked according to the manufacturer's directions. The specimens were roughened with new green stone at 15,000rpm for 30 seconds and sandblasted with $25{\mu}$aluminum oxide for 15 seconds. They were divided into 4 groups at random, and 4 groups were prepared as follows : Group I : specimens were autoglazed and overpolished with polishing system. Group II : specimens were polished with only polishing system. Group III : specimens were glazed after adding glazing liquid, vitachrom 'L'-fluid (vita zahnfabrik co. Germany) to the rough surface Group V : specimens were just autoglazed Using the surface roughness tester, Ra, Rmax. and Rz were estimated 5 times per specimen, and recording process of mean value was repeated 3 times. The results were as follows : 1. The Ra of group I and group II was lower than group III and group IV (p<001). 2. There was lower value of Rz in group I and group II than group III and group IV (p<001). 3. The Rmax of group I (overpolished with polishing system after autoglazing) and group II (polished with only polishing system) was lower than group III (glazed after adding glazing liquid) and group IV (autoglazed) (p<001). 4. There was not a statistically significant difference between group I and II and between group III and IV (p>001). 5. The roughness was increase in order of group I, II, III, IV in SEM

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.494-498
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• 2000

RuO$_2$ thin films are prepared by RF magnetron reactive sputtering and their characteristics of crystallization, microstructure, surface roughness and resistivity are studied with various $O_2$/ (Ar+O$_2$) ratios and substrate temperatures. As $O_2$/(Ar+O$_2$) ratio decreases and substrate temperature increases, the preferred growing plane of RuO$_2$ thin films are changed from (110) to (101) plane. With increase of the $O_2$/(Ar+O$_2$) ratio from 20% to 50%, the surface roughness and the resistivity of RuO$_2$ thin films increase from 2.38nm to 7.81 nm, and from 103.6 $\mu$$\Omega$-cm to 227 $\mu$$\Omega$-cm, respectively, but the deposition rate decreases from 47 nm/min to 17 nm/min. On the other hand, as the substrate temperature increases from room temperature to 500 $^{\circ}C$, resistivity decreases from 210.5 $\mu$$\Omega$-cm to 93.7 $\mu$$\Omega$-cm. RuO$_2$ thin film deposited at 300 $^{\circ}C$ shows a excellent surface roughness of 2.38 nm. As the annealing temperature increases in the range between 400 $^{\circ}C$ and 650 $^{\circ}C$, the resistivity decreases because of the improvement of crystallinity. We find that RuO$_2$ thin film deposited at 20% of $O_2$/(Ar+O$_2$) ratio and 300 t of substrate temperature shows excellent combination of surface smoothness and low resistivity so that it is well Qualified for bottom electrodes for ferroelectric thin films.

• Progress in Superconductivity
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• v.6 no.1
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• pp.69-73
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• 2004

Ni alloy tape is electropolished to be used as a metal substrate for fabrication of IBAD (ion-Beam Assisted Deposition)-MgO texture template fur HTS coated conductor. Electropolishing is needed to obtain a very smooth surface of Ni alloy tape because the in-plane texture of templates is sensitive to the roughness of metal substrate. The critical current of YBCO coated conductor depends on the texture of YBCO that depends on the texture of the IBAD MgO layer. And so the smoothness of the metal substrate is directly related to the superconducting properties of the coated conductor. In this study, we have prepared a reel-to-reel electropolishing apparatus to polish the Ni alloy tapes for IBAD. Various electropolishing conditions were investigated to improve the surface roughness. Hastelloy tape is continuously electropolished with high polishing current density (0.5 ∼ 2 A/$\textrm{cm}^2$) and fast processing time (1 ∼ 3 min). Polished hastelloy tapes have surface roughness(RMS) of below 1 nm on a 5 ${\times}$ 5 $\mu\m^2$ from AFM and SEM.