• 제어로봇시스템학회논문지
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• 제13권7호
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• pp.616-623
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• 2007

A dual micro gas sensor array was fabricated using nano sized $SnO_2$ thin films which had good sensitivities to CO and combustible gases, or $H_2S$ gas for air quality sensors in automobile. The already existed air quality sensor detects oxidizing gases and reducing gases, the air quality sensor(AQS), located near the fresh air inlet detected the harmful gases, the fresh air inlet door/ventilation flap was closed to reduce the amount of pollution entering the vehicle cabin through HVAC(heating, ventilating, and air conditioning) system. In this study, to make $SnO_2$ thin film AQS sensor, thin tin metal layer between 1000 and $2000{\AA}$ thick was oxidized between 600 and $800^{\circ}C$ by thermal oxidation. The gas sensing layers such as $SnO_2$, $SnO_2$(pt) and $SnO_2$(+CuO) were patterned by metal shadow mask for simple fabrication process on the silicon substrate. The micro gas sensors with $SnO_2$(+Pt) and $SnO_2$(CuO) showed good selectivity to CO gas among reducing gases and good sensitivity to $H_2S$ that is main component of bad odor, separately.

• 한국정보통신학회논문지
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• 제10권9호
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• pp.1641-1647
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• 2006

나노입자 크기를 가진 얇은 $SnO_2$ 박막을 이용하여 CO 및 $H_2S$에 대한 우수한 감도를 가지는 복합 마이크로 가스센서 어레이를 제작하였다. 나노입자의 박막을 만들기 위해서 약 $2500{\AA}$ 두께의 $SnO_2,\;SnO_2(+Pt),\;SnO_2(+CuO)$ 막을 셰도우마스크를 사용하여 형성 한 후, 이를 $600{\sim}800^{\circ}C$의 온도에서 산화하므로서 나노입자의 $SnO_2$ 모물질의 가스감지 박막을 형성하였다. 실리콘 기판의 마이크로센서의 형태로 제작된 $SnO_2(Pt)$ 및 $SnO_2(+CuO)$ 가스센서는 각각 CO 및 $H_2S$ 가스에 대한 매우 우수한 감도를 나타내는 것을 확인하였다.

• The Korean Journal of Ceramics
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• 제6권3호
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• pp.304-308
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• 2000

WO$_3$/SnO$_2$ceramics has been suggested as an effective sensing material for monitoring offensive odor or pollutant gases. This work was focussed on improving long-term stability, which has been a principal problem generally taking place in SnO$_2$semiconductor gas sensor. Miniaturized thick film gas sensors were fabricated by screen printing technique. Two types of sensor materials, W doped SnO$_2$and WO$_3$mixed SnO$_2$, were comparatively investigated on those long-term stability and sensitivites to several gases. Small amount of W doping(0.1 mol%) into SnO$_2$largely improved the long-term stability. The W(0.1 mol%) doped SnO$_2$gas sensor had higher sensitivities to both acetone and alcohol compared with WO$_3$(5 wt%) mixed SnO$_2$gas sensor. On the contrary, WO$_3$(5 wt%) mixed SnO$_2$gas sensor showed more superior sensitivity to cigarette smoke due to larger W content.

• 한국세라믹학회지
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• 제27권5호
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• pp.638-644
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• 1990

The C3H8 gas sensitivities of SnO2, Pd-SnO2, Pt-SnO2 gas sensor are looked over with the impregnation method of PdCl2, H2PtCl6 solution on SnO2. The Cl- ion due to incomplete decomposition of PdCl2 at 80$0^{\circ}C$ for 30 min decrease the C3H8 gas sensitivity of SnO2, and the sensitivity is increased by the impreganation of H2PtCl6 solution on SnO2 because of its lower decomposition temperature compared with PdCl2. The C3H8 gas sensitivities of Pd-SnO2, Pt-SnO2 impregnated slightly after 1st sintering are larger than that of pure SnO2 sensor because very small amount of Cl- ion exist in sample due to smaller amount of impregnaiton.

• 센서학회지
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• 제31권5호
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• pp.348-352
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• 2022

Hydrogen gas (H₂) which is odorless, colorless is attracting attention as a renewable energy source in varions applications but its leakage can lead to disastrous disasters, such as inflammable, explosive, and narcotic disasters at high concentrations. Therefore, it is necessary to develop H₂ gas sensor with high performance. In this paper, we confirmed that H₂ gas detection ability of SnO₂ based H₂ gas sensor along with thermal treatment effect of SnO₂. Proposed SnO₂ based H₂ gas sensor is fabricated by MEMS technologies such as photolithgraphy, sputtering and lift-off process, etc. Deposited SnO₂ thin films are thermally treated in various thermal treatement temperature in range of 500-900 ℃ and their H₂ gas detection ability is estimatied by measuring output current of H₂ gas sensor. Based on experimental results, fabricated H₂ gas sensor with SnO₂ thin film which is thermally treated at 700 ℃ has a superior H₂ gas detection ability, and it can be expected to utilize at the practical applications.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.865-868
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• 2002

$SnO_2$ powders were prepare by precipitating $Sn(OH)_4$ from an aqueous solution of $SnCl_4{\cdot}5H_2O$, pH 9.5. The effects of stability and sensitivity of $SnO_2$ thick film sensors added with various amounts, $SiO_2$, $Al_2O_3$, $ZrO_2$, $TiO_2$ have been investigated. It is shown that the 3wt% $Al_2O_3$ or $SiO_2$ can improve the stability of $SnO_2$ gas sensor at an operating temperature of $350^{\circ}C$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.209-212
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• 1991

Recently, oxide semiconductor gas sensors consisted of n-type semiconductor materials such as $SnO_2$, ZnO and $Fe_2O_3$ have been widely used to detect reducing gases. The advantage of thick-film technology include the possibility of mass-production and automation, that of integrating the sensing element in a hybrid circuit and that of fuctional trimming of the sensor and/or the circuit. which would enable really interchangeable transducers to be prepared. In this paper, we made ZnO and $SnO_2$ gas sensors and investigated the sensitivity to CO gas. Therefore, we compared a ZnO gas sensor with a $SnO_2$ gas sensor.

• 센서학회지
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• 제17권3호
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• pp.178-182
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• 2008

Planar type micro catalytic combustible gas sensor was developed by using nano crystalline $SnO_2$ Pt thin film as micro heater was deposited by thermal evaporation method on the alumina substrate. The thickness of the Pt heater was around 160 nm. The sensor showed high reliability with prominent selectivity against various gases(Co, $C_3H_8,\;CH_4$) at low operating temperature($156^{\circ}C$). The sensor with nano crystalline $SnO_2$ showed higher sensitivity than that without nano crystalline $SnO_2$. This can be explained by more active adsorption and oxidation of hydrogen by nano crystalline $SnO_2$ particles. The present planar-type catalytic combustible hydrogen sensor with nano crystalline $SnO_2$ is a good candidate for detection of hydrogen leaks.

• 한국가스학회지
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• 제13권2호
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• pp.23-29
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• 2009

Pt, Pd, In 등의 촉매금속을 사용하여 아세토나이트릴 유독가스에 대한 감도를 향상시키는 SnO2 가스센스에 대하여 연구하였다. Metal-SnO2 후막은 백금전극이 내장된 알루미나 지지체의 스크린법으로 제작되었다. 본 센서의 특성은 검출가스의 농도의 함수로 반응기내 각센서의 전기적 저항을 측정하여 조사하였으며, 10-50ppm 범위의 유독가스 농도에 대하여 검지 측정하였다. 그 결과 촉매금속의 종류에 따라 센서에서 반응하는 감도가 각각 다르게 선택성을 갖고 있는 것으로 나타났다.

• The Korean Journal of Ceramics
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• 제2권2호
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• pp.83-88
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• 1996

Long term stability, sensitization in air, and gas sensing behaviors of tin oxide films were investigated with doping of antimony and palladium. The tin oxide films were prepared on a Corning glass by reactive rf sputtering method and tested for detection of hydrogen gas. Sb-doping improved a long-term stability in the base resistance of $SnO_2$ film sensor. A small amount of Pd doping caused the optimum sensor operating temperature to reduce and also enhanced the gas sensitivity, compared with the undoped $SnO_2$ film. Gas sensitivity depended largely on the film thickness. The important sensitization reactions for sensor operating were $(O_{2ads})+e^-\;{\rightarrow}\;2(O_{ads})^-$ on the surface of $SnO_2$ film at elevated temperature in air and a followed reaction of hydrogen atoms with $(O_{ads})^-$ ions.