• Korean Journal of Materials Research
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• v.18 no.4
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• pp.193-198
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• 2008

$WO_3$-doped $SnO_2$ thin films were prepared in a solution-deposition method and their gas-sensing characteristics were investigated. The doping of $WO_3$ to $SnO_2$ increased the response ($R_a/R_g,\;R_a$: resistance in air, $R_g$: resistance in gas) to $H_2$ substantially. Moreover, the $R_a/R_g$ value of 10 ppm CO increased to 5.65, whereas that of $NO_2$ did not change by a significant amount. The enhanced response to $H_2$ and the selective detection of CO in the presence of $NO_2$ were explained in relation to the change in the surface reaction by the addition of $WO_3$. The $WO_3$-doped $SnO_2$ sensor can be used with the application of a $H_2$ sensor for vehicles that utilize fuel cells and as an air quality sensor to detect CO-containing exhaust gases emitted from gasoline engines.

• Journal of Sensor Science and Technology
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• v.17 no.5
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• pp.361-368
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• 2008

Nanosized $SnO_2$ particles were synthesized by homogeneous precipitation method using tin chloride ($SnCl_4{\cdot}5H_{2}O$) and urea ($CO(NH_2)_2$). The powders were heated at $500^{\circ}C$ and $600^{\circ}C$ for 2h. The crystal structure, microstructure, thermal behavior, specific surface area were analyzed using XRD, FE-SEM, TGA and BET, respectively. The initial resistance and the $H_2$ sensing properties were measured as a function of ${Sb_2}{O_3}$ and Pd doping concentrations. The resistance was decreased with the addition of ${Sb_2}{O_3}$ and the sensitivity for $H_2$ gas was increased with the addition of Pd. Thus, the optimum $H_2$ gas sensing property was obtained in the 0.25.mol% ${Sb_2}{O_3}$ and 1.w% added $SnO_2$ powders.

• Journal of Sensor Science and Technology
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• v.22 no.4
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• pp.302-307
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• 2013

The Sb-doped $SnO_2$ nanowire network sensors were prepared by thermal evaporation of the mixtures between tin and antimony powders. Pure $SnO_2$ nanowire networks showed high sensor resistance in air ($99M{\Omega}$), similar gas responses to 4 diffferent gases (5 ppm $C_2H_5OH$, CO, $H_2$, and trimethylamine), and very sluggish recovery speed (90% recovery time > 800 s). In contrast, 2 wt% Sb-doped $SnO_2$ showed the selective detection toward $C_2H_5OH$ and trimethylamine, relatively low resistance ($176k{\Omega}$) for facile measurement, and ultrafast recovery speed (90% recovery times: 6 - 18 s). The change of gas sensing charactersitics by Sb doping was discussed in relation to gas sensing mechanism.

• Proceedings of the Korea Crystallographic Association Conference
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• 2007.11a
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• pp.29-29
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• 2007

• 한국초전도학회:학술대회논문집
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• v.14
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• pp.38-38
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• 2004

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.551.2-551.2
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• 2006

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2000.05a
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• pp.55-56
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• 2000

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.65-68
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• 2009

본 연구에서는 eagle 2000 glass위에 APCVD(atmospheric CVD)증착법으로 $SnO_2$:F 박막을 제조하였다. 공정 온도, doping 농도, TTC(Tin tetrachloride)와 $H_2O$, $CH_3OH$의 조성비를 공정 변수로 두었으며, 각 변수에 대한 전기적, 광학적 특성 및 결정성을 확인하였다. hall measurement를 이용 제작된 박막의 전기적 특성을 확인 하였고, uv-VIS spectroscopy, hazemeer를 이용 박막의 광학적 특성을 확인 하였다. 또한 XRD, FESEM, AFM을 이용 박막의 결정성 및 표면 특성을 확인 하였다. 박막의 결정성을 결정짓는 증착 온도의 경우 $590^{\circ}C$에서 완벽한 Tetragonal rutile 형태의 결정성을 보였으며 $SnO_2$:F film $1{\mu}m$ thickness에서 $10({\Omega}/{\square})$ 내외의 우수한 면저항값과 $30(cm^2/Vs)$ 이상의 mobility값을 확인 하였으며, 가시광영역대 에서 높은 투과율과 우수한 haze값을 얻었다.

• Journal of Ceramic Processing Research
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• v.19 no.5
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• pp.388-393
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• 2018

Sublimation of $Bi_2O_3$-based materials is an important degradation issue for the long-term applications of many electronic devices. A series of $SnO_2$-doped $Bi_2O_3$ materials (SBO), was synthesized, densified, and then tested in air or strong reducing atmosphere. The $SnO_2$-doping effects and sublimation kinetics of the SBO materials were studied by X-ray diffraction (XRD), scanning electron microscope (SEM) and precise mass loss measurement. The results show that formation of $Bi_2Sn_2O_7$ phase greatly retards the mass loss of SBO. The SBO samples show a surface sublimation in an energy of $52.6kJ{\cdot}mol^{-1}$. However, the sublimation is also controlled by surface microstructure as the amount of vaporizing species (the Bi or gaseous Bi-oxides) is more than 0.1 mass%. The evaporation is retarded on the rough surface and the mechanism of surface evaporation is changed to diffusional control.

• Journal of Magnetics
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• v.13 no.3
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• pp.88-91
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• 2008

This study examined the effect of Sn co-doping on the transport and magnetic properties of Cr-doped $In_2O_3$ thin films grown on (100) silicon substrates by pulsed laser deposition. The experimental results showed that Sn co-doping enhances the magnetization and appearance of the anomalous Hall effect, and increases the carrier (electron) concentration. These results suggest that the conduction carrier plays an important role in enhancing the ferromagnetism of a laser-deposited Cr-doped $In_2O_3$ film, which may have applications in transparent oxide semiconductor spin electronics devices.