• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.8
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• pp.626-631
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• 2012

$SnO_2$ nanoparticles were synthesized by flame spray pyrolysis, which were directly deposited on Pt interdigitated substrates. Gas sensing performance was evaluated for various gases such as $H_2$, CO, $H_2S$, and $NH_3$, and it was compared with that of commercial $SnO_2$ nanopowder. The synthesis of $SnO_2$ nanoparticles was also conducted in various solvents. As a result, the primary particle size was changed with the solvent of precursor solution, and their $H_2$ sensing properties were significantly affected.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.847-849
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• 1992

Fluorine-doped ($SnO_2$:F) thin films obtained by pyrosol deposition method have been exposed to R.F. excited pure hydrogen plasma under the following conditions; substrate temperature of 200$^{\circ}C$, $H_2$ pressure of 1 Torr, R.F. input power of 50 mW/$\textrm{cm}^{2}$, $H_2$ flow rate of 30cc/min and exposure time of 15-600 seconds. It is found that the sheet resistance of the films remains unchanged or rather slightly reduces for initial exposure time of 30-60 seconds, but increases sharply with further increasing the exposure time. The optical transmittance of $SnO_2$:F films slows a rapid fall with increasing exposure time except for a film obtained with a solution having $CH_3OH/H_2O$ mol ratio of 2.65, its degradations at the exposure time of 30-60 seconds are about 7-15%. In addition, the exposure of the films to hydrogen plasma atmosphere leads to remarkable changes in the microstructure and chemical composition, which should be attributed to the reduction of $SnO_2$ to SnO and to elemental Sn.

• Journal of the Korean Society for Heat Treatment
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• v.30 no.2
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• pp.61-66
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• 2017

$SnO_2$ was electrodeposited on nodule-type Cu foil at varing current density and electrodeposition time. Unlike the previous research results, when the anodic current is applied, the $SnO_2$ layer was not electrodeposited and the substrate is corroded. When the cathodic current was applied, the $SnO_2$ layer could be successfully deposited. At this time, the surface microstructure of the powdery type was observed, which showed similar crystallinity to amorphous and had a very large surface area. Crystallinity increased after low-temperature heat treatment at $250^{\circ}C$ or lower. As a result of evaluating the charge/discharge performances as an anode material for lithium ion battery, it was confirmed that the capacity of the heat treated $SnO_2$ was increased more than 2 times, but it still showed a limit point showing initial low coulombic efficiency and low cyclability. However, it was confirmed that the battery performances may be enhanced through optimizing the electrodeposition process and introducing post heat treatment.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.233-233
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• 2014

InGaZnO 박막트랜지스터(TFT)는 기존의 널리 사용되던 비정질 실리콘보다 높은 전하이동도와 Ion/off, 우수한 균일성과 신뢰성의 장점으로 최근 AMOLED양산에 적용되기 시작 하였다. 그러나 60인치 이상의 대면적 디스플레이와 초고해상도의 성능을 동시에 만족하기 위해 10 cm2/Vs정도의 전하이동도를 가지는 InGaZnO로는 한계가 있어 30 cm2/Vs 이상의 전하이동도를 가지는 물질의 연구가 필요하다. 연구에서는 높은 전하이동도를 만족하기 위해 InO2를, 우수한 신뢰성을 가지는 SnO2를 포함하는 InZnSnO로 실험을 진행하였다. 스퍼터링 시스템에서 ITO 타겟과 ZTO 타겟을 사용하여 동시증착법으로 채널을 증착하였고, 산소 분압 변화시에 IZTO TFT 소자 특성의 의존성을 평가하였다. Ar : O2=10 : 0 일 때와 Ar : O2=7 : 3 일 때의 이동도가 각각 12.6cm2/Vs, 19.7cm2/Vs로 산소 비율이 증가함에 따라 전하이동도가 증가하였다. 기존 IGZO 산화물 반도체에서는 산소 비율이 증가하면 산소공공(VO) 농도감소로 인해 전하이동도가 감소한다. 이는 전하농도가 증가하면 전하이동도가 증가하는 percolation 전도기구로 이해할 수 있다. 그러나 본 IZTO 물질에서는 산소비율 증가에 따라 오히려 전하이동도가 증가하였는데, 이는 IZTO 반도체에 함유된 Sn 이온의 가전자상태가 +2/+4가의 상대적 비율이 산소농도에 따라 의존하기 때문인 것으로 분석되었다.

• Journal of the Korean Ceramic Society
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• v.36 no.12
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• pp.1322-1326
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• 1999

In2O3 thick film gas sensor for detecting NOx gas of high concentration was fabricated by a screen printing technique. This work focussed on investigation of the change of sensitivity to NOx gas with firing temperatures of sensing layer and on improvement of the sensitivity by adding catalysts such as Al,. Ru, and SnO2 The cross sensitivites of sensor to CO, H2, CH4 and i-C4H10 gases were also examined under NO2 gas concentration of 200ppm Pure In2O3 gas sensor prepared at a firing temperature of 50$0^{\circ}C$ showed a maximum sensitivity to NOx gas at the operating temperature of 40$0^{\circ}C$ Al(0.004 wt%)-In2O3 sensor largely improved the sensitivities to both NO2 and NO gas and showed a superior selectivity compared with other gas sensors.

• Journal of the Korean Society for Heat Treatment
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• v.34 no.6
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• pp.265-271
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• 2021

In this study, anti-tarnishing and corrosion characteristics of a single 𝛽1' and Bangjja Yugi alloy in the Cl^- ion environment before and after potentiostatic electrolysis treatment were compared. Stable and uniform SnO₂ oxide film with several nanometer thickness is formed after potentiostatic electrolysis treatment. In the case of Bangjja Yugi prior to potentiostatic electrolysis (PE) treatment for exposure in Cl^- environment, tarnishing occurs rapidly within 0.5hr, whereas PE treated Bangjja Yugi indicates stable surface without tarnishing up to 3hr. Especially, it is noticeable that anti-tarnishing and corrosion characteristic of PE treated single 𝛽1', which were significantly improved by 3 times and 15 times, respectively, compared to conventional Bangja Yugi.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.4
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• pp.935-938
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• 2010

Indium-tin-oxide (ITO) films show a low electrical resistance and high transmittance in the visible range of an optical spectrum. The transparent electrodes have to get resistivity and sheet resistance less than $1{\times}10^{-3}{\Omega}/cm$ and $10^3{\Omega}/sq$ respectively and transmittance over 80% at wavelength of 380nm~780nm. This study establishes DC magnetron sputtering process condition on ITO thin film by measuring electrical and optical properties of the thin film. As results, we obtained $300\;{\mu}{\Omega}cm$ resistivity of ITO films with good transmittance (above 90 %) under 90:10 wt% composition rate of $In_2O_3:SnO_2$. Also, we understood that the ITO thin film by DC magnetron sputtering depends on the deposition condition, especially substrate temperature, and the composition rate of $In_2O_3:SnO_2$ that is one of the most critical parameters was successfully optimized for high qualified transparent electrodes.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1555-1557
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• 2004

The Pt-doped $SnO_2$ thin film for CO sensor applications obtained by RF sputtering from a target of the same compound in an Ar-$O_2$ atmosphere. Pt-SnO2-SiC Schottky diode detection of CO gas Cause the remarkable change in electrical resistivity of the semiconductor. the good gas sensitivity is shown when annealing condition is 600$^{\circ}C$, 1hr in RTP and detected temperature is 350$^{\circ}C$.

• Korean Journal of Materials Research
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• v.17 no.7
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• pp.376-381
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• 2007

Fluorine-doped tin oxide (FTO) thin film was coated on aluminosilicate glass at $450^{\circ}C$ by spray pyrolysis method. In the range of 0-2.7 molar ratio of F/Sn, the variations of electrical conductivity and visible light transmission were investigated. At the F/Sn ratio of 1.765, the film showed the lowest electrical resistivity value of $3.0{\times}10^{-4}{\Omega}\;cm$, the highest carrier concentration of $2.404{\times}10^{21}/cm^3$, and about $8\;cm^2/V{\cdot}sec$ of electronic mobility. The FTO film showed a preferred orientation of (200) plane parallel to the substrate. X-ray photoelectron spectroscopy analysis results indicated that the contents of $Sn^{4+}-O$ bonding are the highest at 1.765 of F/Sn molar ratio.

• Journal of the Korean Society for Heat Treatment
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• v.25 no.5
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• pp.239-243
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• 2012

$SnO_2$ thin films were prepared on the Si substrate by radio frequency (RF) magnetron sputtering and then post deposition vacuum annealed to investigate the effect of annealing temperature on the structural properties and hydrogen gas sensitivity of the films. The films that annealed at $300^{\circ}C$ show the higher sensitivity than the other films annealed at $150^{\circ}C$. From atomic force microscope observation, it is supposed that post deposition annealing promotes the rough surface and also, increase gas sensitivity of $SnO_2$ films for hydrogen gas. These results suggest that the vacuum annealed $SnO_2$ thin films at optimized temperatures are promising for practical high-performance hydrogen gas sensors.