• Korean Journal of Metals and Materials
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• v.48 no.12
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• pp.1084-1089
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• 2010

This study elucidates the formation mechanism of SnO plate observed during the precipitation reaction of a $SnCl_2$ aqueous solution. $Sn_{21}Cl_{16}(OH)_{14}O_6$ and $Sn_6O_4(OH)_4$ precipitates was formed at pH=3~5 and at pH=11, respectively. When the pH was in the range of 11.5~12.5, the $Sn_6O_4(OH)_4$ precipitates dissolved into $HSnO_2{^-}[Sn_6O_4(OH)_4+4OH^-={6HSnO_2{^-}+2H^+]$ and dissolved $HSnO_2{^-}$ ions reprecipitated to SnO plate $[HSnO_2{^-}+H^+=SnO+H_2O]$. The $Sn_6O_4(OH)_4$ precipitates completely transformed into SnO plate through a repeated process of dissolution-precipitation in the range of pH=11.5~12.5.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.91-91
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• 2008

$SnO_2-B_2O_3-P_2O_5$ system were prepared by melt-quenching technique in the compositional series containing 50, 55 aod 60mol.% of $SnO_2$. A large glass-forming region was found at the phosphate side of the ternary system with homogeneous glasses containing up to 5-25mol.% of $B_2O_3$. For these glasses, thermal expansion coeffient($\alpha$), glass transition temperature(Tg), and glass softening temperature(Ts), were determined. The values a decrease with increasing $B_2O_3$ content, while Tg and Ts increased. The reason for the observed changes is local structure of the glasses. Local structure of the glasses was investigated by Raman and FT-IR measurements, suggesting that the number of bridging oxygens decreased whereas the non-bridging oxygen concentration increased with increasing $SnO_2$ content in the glasses.

• Journal of the Korean Ceramic Society
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• v.45 no.8
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• pp.459-463
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• 2008

$P_2O_5-SnO_2$ system $0.5SnO_2-xP_2O_5-(0.5-x)B_2O_3$(x=0.1, 0.2, 0.3, 0.4, 0.5) glasses have been prepared for Pb-free low temperature glass frit. A investigation about the effect of $B_2O_3$ substitution on properties of $P_2O_5$ glasses, including glass structure properties, thermal properties, and mechanical properties was presented. Substance that is responsible for in moisture absorption existing circumstances supposes by phosphate, and excess moisture tolerance that state funeral's structure is improved breaking does not affect in state funeral bond that only most single bond remains, and can know that does not suffer big impact in boric oxide anomaly present state. This phenomenon estimates that connect with structure change. It is thought according to link this result the phosphoric acid happened structural change. $B_2O_3$ displacement quantity 0.3 mole put out $BO_4$ structures, but above 0.3 mole it changed with the case $BO_3$ structure which it displaces.

• Korean Journal of Materials Research
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• v.4 no.7
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• pp.759-766
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• 1994

Our investigation aimed to reduce the leakage current of $Ta_2O_5$ thin film capacitor by layering SnOz thin film layer under Ta thin film, thereby supplying extra oxygen ions from the $SnO_{2}$ underlayer to enhance the stoichiometry of $Ta_2O_5$ during the oxidation of Ta thin film. Tantalum was evaporated by e-beam or sputtered on p-Si wafers with various deposition temperatures and was oxidized by dry--oxygen at the temperatures between $500^{\circ}C$ and $900^{\circ}C$. Aluminum top and bottom electrodes were formed to make Al/$Ta_2O_5$/p-Si/Al or $Al/Ta_2O_5/SnO_2$p-Si/AI MIS type capacitors. LCR meter and pico-ammeter were used to measure the dielectric constants and leakage currents of the prepared thm film capacitors. XRD, AES and ESCA were employed to confirm the crystallization of the thin f~lm and the compositions of the films. Dielectric constant of $Ta_2O_5$ thin film capacitor with $SnO_{2}$ underlayer was found to be about 200, which is about 10 times higher than that of $Ta_2O_5$ thin film capacitor without $SnO_{2}$ underlayer. In addition, higher oxidation temperatures increased the dielectric constants and reduced the leakage current. Higher deposition temperature generally gave lower leakage current. $Ta_2O_5/SnO_2$ capacitor deposited at $200^{\circ}C$ and oxidized at $800^{\circ}C$ showed significantly lower leakage current, $10^{-7}A/\textrm{cm}^2$ at $4 \times 10^{5}$V/cm, compared to the one without $SnO_{2}$ underlayer. XRD showed that $Ta_2O_5$ thin film was crystallized above $700^{\circ}C$. AES and ESCA showed that initially the $SnO_{2}$, underlayer supplied oxygen ions to oxidize the Ta layer, however, Sn also diffused into the Ta thin film layer to form a new $Ta_xSn_YO_Z$ , ternary oxide layer after all.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.206-207
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• 2005

Display 소재로서 유전체나 격벽재 실링재로 사용되고 있는 frit는 PbO를 주성분으로 갖는 유리가 사용되고 있다. PbO 성분이 함유된(50$\sim$85%) 구성소재는 최근 RoHS 나 WEEE 등의 환경규제 실행에 직면해 있으며, 대체재료의 개발을 위한 많은 연구가 진행되고 있다 PbO 성분을 대체할 성분으로는 $Bi_2O_3$ 계, BaO-ZnO 계, $P_2O_5$ 계 등의 성분이 주요성분으로 이루어져 있으며, PbO 성분을 함유한 유리의 저융점, 저유전율, 고 투과율, 내산성, 내전압, 팽창계수 matching 등의 특성들에 부합되는 재료를 개발하기 위해 많은 노력을 기울이고 있다. 본 연구에서는 SnO-$P_2O_5$ 계 유리 조성을 선택하여 $R_2O_3$의 치환 및 용융분위기의 조절에 따른 저융점 유리로서의 특성과 효과에 대하여 고찰하였다.

• Journal of the Korean Ceramic Society
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• v.48 no.1
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• pp.63-68
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• 2011

The investigation is directed to lead free (Pb-free) frits that can be used for organic light emitting diode, plasma display screen devices and other sealing materials. $P_2O_5$-SnO system glasses have been prepared for Pb-free low temperature glass frit. Structure and properties of the glasses with the composition SnO-$xB_2O_3-(60-x)P_2O_5$ (x=0, 5, 10, 15, 20, 25, 30, 35, 40 mol%) were characterized by infrared spectra (IR), X-ray diffraction(XRD), Density, Molar volume, Thermo mechanical analysis(TMA) and weight loss after immersion test. Glass transition temperature($T_g$), dilatometric softening temperature($T_d$) and chemical durability increased, and coefficient of thermal expansion($\alpha$) decrease with the substitution of $B_2O_3$ for $P_2O_5$ in the range of 0~25 mol%.

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.107.2-107
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• 2002

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.11a
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• pp.162-162
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• 2002

• 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 $350^{\circ}C$.

• Journal of the Korean Institute of Telematics and Electronics
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• v.13 no.2
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• pp.23-27
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• 1976

$Si{\cdot}SnO_{2}$ heterojunction was prepared by oxidzing at oxygen atmosphere $SnO_{2-X}$ Which made by Flith evaporation of $SnO_{2}$ powder on III surface of p and n type Si single crystals. The energy band Profile of $Si{\cdot}SnO_{2}$ heterojunction was depicted from its physical properties. This heterojunction was very good rectifying junction, very sensitive in spectral response of Photovoltage at from 400nm to 1200nm, and -10$^{18}$sec of time contant. From above properties, this heterojunction was found ps good high speed photovoltaic device and solar cell.