• Korean Journal of Materials Research
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• v.10 no.11
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• pp.778-783
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• 2000

Effects of the $Al_2$O$_3$surface protective layer, deposited on the SnO$_2$sensing layer by aerosol flame deposition (AFD) method, on the sensing properties of SnO$_2$thin film ags sensors were investigated.Effects of Pt doping to the $Al_2$O$_3$surface protective layer on the selectivity of CH$_4$ gas were also investigated. 0.3$\mu\textrm{m}$ thick SnO$_2$thin sensing layers on Pt electrodes were prepared by R.F. magnetron sputtering with R.F. power of 50 W, at working pressure of 4mTorr, and at 20$0^{\circ}C$ for 30 min. $Al_2$O$_3$surface protective layers on SnO$_2$layers were prepared by AFD using a diluted aluminum nitrade (Al(NO$_3$).9$H_2O$) solution. The sensitivity of CO gas in the SnO$_2$gas sensor with an $Al_2$O$_3$surface protective layer was significantly decreased. But that of CH$_4$gas remained almost same with pure SnO$_2$gas sensor. This result shows that the selectivity of CH$_4$gas is increased because of the $Al_2$O$_3$surface protective layer. In the case of SnO$_2$gas sensors with Pt-doped $Al_2$O$_3$surface protective layers, low sensing property to CO gas and high sensing property to CH$_4$were observed. This results in the increasing of selectivity of CH$_4$gas selectivity are discussed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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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 $350^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• v.18 no.12
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• pp.1291-1295
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• 1997

The catalytic dehydrocoupling of di-n-butylstannane n-Bu2SnH2 by the Cp2MCl2/Red-Al (M = Ti, Zr, Hf) and M(CO)6/Red-Al in situ combination catalysts yielded a mixture of two kinds of catenated products: one is a cross-linked insoluble solid, and the other is a non-cross-linked soluble solid (≒Sn5) or viscous oil (≒Sn2). The soluble oligostannanes could be produced by simple dehydrocoupling of n-Bu2SnH2, whereas the insoluble polystannanes could be obtained via disproportionation/dehydrocoupling combination process of n-Bu2SnH2. The disproportionation/dehydrocoupling combination process may initially produce a low-molecular-weight oligostannane with partial backbone Sn-H bonds which could then undergo an extensive cross-linking reaction of backbone Sn-H bonds, resulting in the formation of an insoluble polystannane.

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.94-94
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• 2002

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.78-78
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• 2002

• Proceedings of the Materials Research Society of Korea Conference
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• 2001.05a
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• pp.131-131
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• 2001

• Proceedings of the KWS Conference
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• 1999.05a
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• pp.96-97
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• 1999

• Proceedings of the Materials Research Society of Korea Conference
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• 2001.11a
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• pp.110-110
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• 2001

• Proceedings of the Materials Research Society of Korea Conference
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• 2000.11a
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• pp.70-70
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• 2000

• Proceedings of the Materials Research Society of Korea Conference
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• 1997.05a
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• pp.76-76
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• 1997