• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 C
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• pp.1410-1412
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• 2003

PTC 자기발열기판을 사용해서 저전력 방폭형 CO센서를 제작하고 그 특성을 고찰하였다. CO가스센서의 감지특성을 향상시키기 위하여 Pt가 island 형상을 갖는 다층 Pt/$SnO_2$ 박막구조를 도입하였으며, 이와 같은 구조는 Pt/$SnO_2$ 위에 다시 $SnO_2$ 및 Pt cluster 층들을 연속적으로 증착함으로서 제작되었다. 200ppm의 CO가스농도에서 측정된 다층 $Pt/SnO_2$박막 센서의 감도는 1.72($R_{air}/R_{CO}$)로, 단충 Pt/$SnO_2$ 박막 센서의 최대감도(1.23)보다 훨씬 더 높았다 이것은 Pt와 $SnO_2$사이의 계면적 증대에 기인하는 것으로 생각된다. 제작된 Pt/$SnO_2$ 가스센서의 평균 소비전력은 38.5mW이며, 측정농도범위($30{\sim}1,000ppm$)에서 매우 양호한 감지특성을 나타내었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
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• pp.79-81
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• 2004

$TiO_2-SnO_2$ thin films are fabricated using sol-gel method. The thickness of thin films increase about $0.03{\sim}0.04{\mu}m$ every a dipping. The permittivity and dissipation factor of $TiO_2-SnO_2$ thin films decrease with increasing frequency. Thin films show semiconductive characteristics above $400^{\circ}C$.

• 한국재료학회지
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• 제24권3호
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• pp.152-158
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• 2014

We report the effect of the fabric of the surface microstructure on the CO gas sensing properties of $SnO_2$ thin films deposited on self-assembled Au nanodots ($SnO_2$/Au) that were formed on $SiO_2/Si$ substrates. We characterized structural and morphological properties, comparing them to those of $SnO_2$ thin films deposited directly onto $SiO_2/Si$ substrates. We observed a significant enhancement of CO gas sensing properties in the $SnO_2$/Au gas sensors, specifically exhibiting a high maximum response at $200^{\circ}C$ and quite a low detection limit of 1 ppm level in dry air. In particular, the response of the $SnO_2/Au$ gas sensor was found to reach the maximum value of 32.5 at $200^{\circ}C$, which is roughly 27 times higher than the response (~1.2) of the $SnO_2$ gas sensor obtained at the same operating temperature of $200^{\circ}C$. Furthermore, the $SnO_2/Au$ gas sensors displayed very fast response and recovery behaviors. The observed enhancement in the CO gas sensing properties of the $SnO_2/Au$ sensors is mainly ascribed to the formation of a nanostructured morphology in the active $SnO_2$ layer having a high specific surface-reaction area by the insertion of a nanodot form of Au nucleation layer.

• 한국표면공학회지
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• 제23권2호
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• pp.18-23
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• 1990

Thin films of tin oxide were prepared by chemical vapor deposition (C.V>D) using the hydrolysis reaction of SnCl4, Deposition rate increased with the increase of temperature up to $500^{\circ}C$and then decreased at $700^{\circ}C$, Deposition rate with SnCl4 partial pressure showed RidealEley behavir. It was found that SnO2 thin film deposited at the temperature above $400^{\circ}C$ had(110) and (301) plane preferred orientation with crystallinity of rutite structure. Electrical resisvity of SnO2 thin film decreased with increase increase of deposition temperature and showed minimum value of 10-3 ohm at $500^{\circ}C$and than largely increased increased with further increase of deposition temperture.

• 한국진공학회지
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• 제10권3호
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• pp.289-297
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• 2001

가연성 가스의 검지 및 인식을 위하여, SnO$_2$계열의 4가지 종류의 박막을 형성하였다. 감지막 형성을 위하여, Sn, Pt/Sn, Au/Sn 그리고 Pt, Au/Sn 막을 Sn의 열증착과 귀금속의 스퍼터링으로 증착하였다. 증착된 박막들을 $700^{\circ}C$ 정도에서 2 시간 열산화시켜 $SnO_2$계열의 감지막을 형성하였다. 제작된 박막은 tetragonal구조의 $SnO_2$이었고, 가스 흡착을 위한 가스 흡착점과 기공도를 많이 갖고 있었다. 스퍼터로 형성된 박막보다 열산화법으로 형성된 박막이 고감도를 보였다. 제작 박막들은 작업환경기준치정도의 저농도에서 측정 가연성 가스(부탄, 프로판, LPG, 일산화탄소)에 대해 고감도와 재현성을 나타내었다. 특히, 백금(30 $\AA$)을 첨가한 박막이 LPG와 부탄 가스에 대해, 순수 열산화된 $SnO_2$ 박막이 프로판과 일산화탄소에 대하여 가장 고감도를 나타내었다. 이들 센서들의 각 가스별로 차별화된 감도패턴을 이용하여 주성분 분석 기법을 통해 환경기준치(LEL, TLV) 범위에서 부탄, 프로판, LPG, 일산화탄소와 같은 가연성 가스의 종류 인식 및 정량을 인식할 수 있었다.

• 한국세라믹학회지
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• 제23권3호
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• pp.53-61
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• 1986

A gas sensor which has been made by wet process had fabricated by coating each of the mixture on alumina tube and firing at 85$0^{\circ}C$ for 3hrs. A gas concentration such $H_2$, CO, $C_3H_8$, $C_2H_2$ and $CH_4$ vs its detection voltage characteristics has been in-vestigated on $SnO_2-In_2O_3-MgO$ system doped with PdO, $La_2O_3$, $ThO_2$, NiO and $Nb_2O_5$ The optimum sensitivity composition for various gases were 90w/o $SnO_2$-9w/o $In_2O_3$-1w/o MgO for $H_2$, $C_2H_2$ CO and $C_3H_8$ and 95w/o $SnO_2$-4w/o $In_2O_3$-1w/o MgO for $CH_4$. The sample which has been made by wet process than dry process had predominated sensitivity for each gases and particle size of the sample coprecipitated with PH=9 was 0.1${\mu}{\textrm}{m}$ The $SnO_2$-In2_O_3-MgO$ system doped with 2w/o $Nb_2O_5$ and NiO was the most sensitive for $H_2$ and $C_2H_2$ gas. In $SnO_2$-In2_O_3-MgO$ system doped with $ThO_2$ the sensitivity of $H_2$ gas was decreased but CO gas was in-creased when dopant con was increased.

• 한국분말재료학회지
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• 제29권5호
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• pp.357-362
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• 2022

The low-temperature sinterability of TiO₂-CuO systems was investigated using a solid solution of SnO₂. Sample powders were prepared through conventional ball milling of mixed raw powders. With the SnO₂ content, the compositions of the samples were Ti_1-xSn_xO₂-CuO(2 wt.%) in the range of x ≤ 0.08. Compared with the samples without SnO₂ addition, the densification was enhanced when the samples were sintered at 900℃. The dominant mass transport mechanism seemed to be grain-boundary diffusion during heat treatment at 900℃, where active grain-boundary diffusion was responsible for the improved densification. The rapid grain growth featured by activated sintering was also obstructed with the addition of SnO₂. This suggested that both CuO as an activator and SnO₂ dopant synergistically reduced the sintering temperature of TiO₂.

• 한국표면공학회지
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• 제40권6호
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• pp.258-261
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• 2007

Relationships between the electrical resistivity and the growth characteristic of $SnO_2$ thin films were investigated. $SnO_2$ thin films with thickness from 64 nm to 91 nm were made by controlling the RF deposition energy from 80 to 150 W. These $SnO_2$ thin films were annealed at $200^{\circ}C{\sim}700^{\circ}C$ temperature range of $100^{\circ}C$ interval in the $O_2$ gas condition. After annealing treatments, the microstructures of the $SnO_2$ thin films were changed mixed structure(amorphous & crystalline) to lamina columnar crystalline structure. Both the film thickness and the grain size were increased with increasing the local crystallization of $SnO_2$ microstructure of thin films by annealing treatment. Their electrical resistivity increased up to the annealing temperature of $400^{\circ}C$, and then slowly decreased.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 추계총회,초청강연,특별강연,연구발표회
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• pp.155.2-155
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• 2000

• 마이크로전자및패키징학회지
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• 제8권1호
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• pp.27-32
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• 2001

($Zr_{0.8}, Sn_{0.2})TiO_4$의 소결온도를 저하시키고 품질계수 향상의 목적으로 첨가한 $V_2O_5$가 다른 donor형태의 화합물과 달리 품질계수의 저하를 가져오는 원인을 $Ta_2O_5$가 첨가된 ($Zr_{0.8}, Sn_{0.2})TiO_4$와 미세 구조변화, 전기전도도, 산화상태의 관점에서 비교 분석하였다. 일반적으로 donor형태의 화합물의 첨가는 ($Zr_{0.8}, Sn_{0.2})TiO_4$의 산소공공의 농도를 감소시켜 품질계수의 증가를 가져오는 것으로 알려져 있다. $V_2O_5$의 첨가의 경우는 액상소결에 의한 결정입계상 존재, 섬유상 형태의 $V_2O_5-TiO_2$rich 이차상 형성 및 Vanadium 이온의 산화상태 불안정에서 기인된 산소공공의 농도 증가가 복합적으로 ($Zr_{0.8}, Sn_{0.2})TiO_4$의 품질계수 저하 요인으로 작용하였다.