• 한국진공학회:학술대회논문집
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• 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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• pp.210-210
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• 2000

Vertically well aligned multi-wall carbon nanotubes (CNT) were grown on nickel coated glass substrates by plasma enhanced hot filament chemical vapor deposition at low temperatures below 600$^{\circ}C$. Acetylene and ammonia gas were used as the carbon source and a catalyst. Effects of growth parameters such as pre-treatment of substrate, plasma intensity, filament current, imput gas flow rate, gas composition, substrate temperature and different substrates on the growth characteristics of CNT were systematically investigated. Figure 1 shows SEM image of CNT grown on Ni coated glass substrate. Diameter of nanotube was 30 to 100nm depending on the growth condition. The diameter of CNT decreased and density of CNT increased as NH3 etching time etching time increased. Plasma intensity was found to be the most critical parameter to determine the growth of CNT. CNT was not grown at the plasma intensity lower than 500V. Growth of CNT without filament current was observed. Raman spectroscopy showed the C-C tangential stretching mode at 1592 cm1 as well as D line at 1366 cm-1. From the microanalysis using HRTEM, nickel cap was observed on the top of the grown CNT and very thin carbon amorphous layer of 5nm was found on the nickel cap. Current-voltage characteristics using STM showed about 34nA of current at the applied voltage of 1 volt. Electron emission from the vertically well aligned CNT was obtained using phosphor anode with onset electric field of 1.5C/um.

• Current Photovoltaic Research
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• 제5권1호
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• pp.1-8
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• 2017

Two different fluorine-doped tin oxide (FTO)-coated glass substrates were investigated to find better suitability for CdTe solar cells. Substrate A consisted of FTO (300 nm)/$SiO_2$ (24 nm)/intrinsic $SnO_2$ (30 nm)/borosilicate glass (2.2 mm), and substrate B consisted of FTO (700 nm)/intrinsic $SnO_2$ (30nm)/borosilicate glass (1.8 mm). The overall thickness of the FTO/glass substrates was about 2.5 mm. The total light transmittance of substrate B was much higher than that of substrate A throughout the whole spectral region, even though the thickness of the FTO in substrate B was twice larger than that of the FTO in the substrate A. The short-circuit current greatly increased in substrate B and the external quantum efficiency (EQE) increased over the whole wavelength range. This study shows that the diffuse optical transmittance played a key role in the large EQE value in the blue wavelength region, and the direct transmittance played a key role in the large EQE value in the red wavelength region. The higher transmittance is due to the rough surface generated by the thicker FTO on glass. The conversion efficiency of the CdTe solar cell increased from 12.4 to 15.1% in combination of rough FTO substrate and Cu solution back contact.

• E2M - 전기 전자와 첨단 소재
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• 제8권1호
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• pp.6-12
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• 1995

High Tc superconducting YBa$_{2}$Cu$_{3}$$O_{7-x}$ thin films were prepared on various substrates by off-axis rf magnetron sputtering method to examine the substrate effects on the film structure and its R-T characteristics. The SEM analysis showed that the surface morphology of the grown YBa$_{2}$Cu$_{3}$O.sub 7-x/, film has different characteristic structure with different substrate used. The film on (100) SrTiO$_{3}$ substrate has critical current density of 3*10$^{5}$ A/cm$^{2}$ at 77K under zero magnetic field. The X-ray diffraction measurements revealed that the films on (100) SrTiO$_{3}$ substrate have mixed a-axis and c-axis normal to the substrate surface and the films on (100) MgO and ZrO$_{2}$/sapphire substrates have c-axis normal orientation to the substrate surface. However, YBa$_{2}$Cu$_{3}$$O_{7-x}$ films on (100) sapphire substrates showed no preferential orientation.ion.

• 한국물환경학회지
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• 제34권1호
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• pp.10-25
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• 2018

This study was conducted to estimate the habitat suitability of 17 benthic macroinvertebrate taxa in the Hwayang stream. Habitat Suitability Index (HSI) of benthic macroinvertebrates from the Hwayang stream was developed based on three physical habitat factors which include current velocity, water depth, and the substrate. The Weibull model was used as a probability density function to analyze the distribution of individual abundance by physical factors. The number of species and the total individual abundance increased along with the increase in current velocity. By means of Canonical Correspondence Analysis (CCA), the relative importance of each factor was determined in the following order: current velocity, water depth, and the mean diameter. The results depicted that, the most influential factor in the growth of benthic macroinvertebrates in the Hwavang system was current velocity. After comparing the analyzed results from the Hwayang stream with the resukts from the Gapyeong stream, the integrated HSI was drawn. The results indicated that current velocity and substrate had similar distributions of HSI in the two streams. This was due to the addition of unmeasured data from previous surveys, or the fact that benthic macroinvertebrates adapted to deeper waters in the Hwayang Stream. Most taxa showed a clear preference for a fast current velocity, deep water depth and coarse substrate except Baetiella, Epeorus, (mayflies), and Hydropsyche (caddisfly).

• Restorative Dentistry and Endodontics
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• 제46권4호
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• pp.55.1-55.9
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• 2021

Objectives: The purpose of this systematic review was to collect and discuss the technique of adhesive systems application on dentin substrate under electric current. Materials and Methods: The first search strategy was based on data available at PubMed, LILACS, Scielo, Scopus, and Cochrane Library, using a combination of descriptors such as "dentin bond agents OR adhesive system AND electric current OR electrobond" or "dentin bonding agents OR dentin bonding agent application OR adhesive system AND electric current OR electrobond", with no limit regarding the publication year. The second search strategy was based on the articles' references found previously. An additional search strategy was applied that concerned the proposed theme in the SBU-UNICAMP (Unicamp's Library System Institutional Repository). Results: Twelve studies published between 2006 and 2020 were found. The analyses of the selected studies showed that the use of electric current during adhesive systems application on dentin, whether conventional or self-conditioning, increases resinous monomer infiltration in the dentin substrate, which improves the hybridization processes and the bond strength of the restorative material to dentin. Conclusions: Despite the favorable results related to the use of this technique, there is still no specific protocol for the application of adhesive systems under electric current.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.87-90
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• 1999

We have studied the annealing effects of 570 (SrTiO$_3$) single crystal substrate and the I-V properties of step-edge junctions after Ar ion milling. YBa$_2Cu_3O_7$ (YBCO) thin films are fabricated on the substrates by using pulsed laser deposition (PLD) and photolithography. The surface of Ar ion milled substrate was characterized with atomic force microscope (AFM) and scanning electron microscope (SEM) images. After the substrate was damaged by milling, the critical current density of YBCO thin films deposited on the substrate was lowered. The annealing of the damaged substrate at about 1000 $^{\circ}C$ recovered the critical current density to that before the milling. Futhermore the annealing helped junction formation due to high quality film and increased the yield rate for the fabrication of high quality step-edge junction.

• 대한전자공학회논문지SD
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• 제40권7호
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• pp.481-485
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• 2003

25㎛ 두께의 폴리이미드 박핀 기판을 glass 기판에 부착하여 최대 온도 150℃에서 비정질 실리콘 TFT를 제작하였다. 본 논문은 plastic 기판 위에 TFT가 제작되는 공정 절차를 요약하고 glass 위에 제작된 TFT와 ON/OFF 전달특성과 전계효과 이동도를 서로 비교해 보았다. a-SiN:H 코팅층은 plastic 기판의 표면 거칠기를 감소시키는 중요한 역할을 하여 TFT의 누설전류를 감소시키고 전계효과 이동도를 증가시켰다. 따라서 a-SiN:H 코팅층을 이용하여 plastic 기판에 양철의 TFT를 제작하였다.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.83-86
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• 1999

We have fabricated $_2Cu_3O_7$ step-edge junctions with different step orientations and studied their transition properties. Steps with different orientations were prepared on the substrate. Josephson junctions were made on a single substrate with step orientations ranging from 0$^{\circ}$ to 165$^{\circ}$ at 15$^{\circ}$ interval. We measured current-voltage characteristics, the critical current, and the superconducting transition temperature as a function of the angle. The critical current showed a modulation that has a maximum near 0$^{\circ}$ or 90$^{\circ}$ and a minimum near 45$^{\circ}$ and 135$^{\circ}$. We believe that the critical current modulation with the step orientation could be associated with the symmetry of high T$_c$ superconductor.

• 마이크로전자및패키징학회지
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• 제7권3호
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• pp.27-29
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• 2000

Lift-off를 이용한 DLC-coated Si-tip FEA 제조에 있어서 gate 절연막의 측면에 DLC가 coating되는 것을 방지하기 위해 기판 상에 Al 희생층을 경사-회전 증착한 뒤 DLC를 coating하고, 다음으로 희생층을 식각하여 tip 이외의 DLC를 제거하는 방법을 제안하였다. 이러한 Al희생층을 이용한 lift-off공정에 의해 제조된 DLC-coated Si-tip FEA의 전류전압 특성과 전류 표동 특성을 조사하였으며, gate 누설 전류의 감소와 방출 전류의 안정성을 확인하였다.

• 한국세라믹학회지
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• 제32권4호
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• pp.441-447
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• 1995

Ba0.65Sr0.35TiO3 (BST) thin films were deposited on Pt/SiO2/Si(100) substrate by rf magnetron sputtering. The substrate temperature changed from 35$0^{\circ}C$ to 55$0^{\circ}C$ and crystalline BST thin films were deposited above 45$0^{\circ}C$. Most of the films had (111) preferred orientation regardless of deposition temperature, but the films changed to (100) preferred orientation as gas pressure increased. The dielectric constant increased with increasing substrate temperature and film thickness, and ranged from 100 to 600 at room temperature. The leakage current increased as substrate temperature increased or as film thickness decreased.