• Bulletin of the Korean Chemical Society
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• 제10권4호
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• pp.343-346
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• 1989

Dicyclohexyltin(IV) complexes $Cy_2SnX (X = O,\;S,\;(Me_2NCS_2)_2)$ have been prepared and characterized by means of elemental analysis, cryoscopic data, and IR spectroscopy. X-ray structure determination for $Cy_2Sn(S_2CNMe_2)_2$ (monoclinic; P2/c;a = 8.992(1), b = 6.688(1), c = 19.453(2) ${\AA},\;{\beta}$ = 96.556(7) ; R = 0.041) has shown that the molecule is $C_2$-symmetric with both dithiocarbamate ligands bonding in anisobidentate mode and the local geometry around the hexacoordinate Sn(IV) atom is a distorted octahedral arrangement with the two cyclohexyl groups in trans position. The physical and chemical properties measured suggest polymeric and trimeric structures for $Cy_2SnO\;and\;Cy_2SnS$, respectively.

• 한국표면공학회지
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• 제39권6호
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• pp.276-281
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• 2006

In order to improve the performance of PPFs (Pre-Plated Frames), a PPF that employed a Cu-Sn alloy instead of conventionally used Ni was developed and then its properties were investigated. It was found that the electoplated Cu-Sn alloy layer was a mixture of uniformly distributed fine crystallites, resulting In better wettability and crack resistance than those of Ni PPF. Moreover, as in Cu/Ni/Pd/Au PPF, migration of copper atoms from the base metal to the top of the Cu/Cu-Sn/Pd/Au PPF surface was not found although the Cu-Sn layer itself contained considerable amount of copper. It was expected that, by using the newly developed Cu-Sn PPF, any possible heat generation and signal interrupt caused by an external electro-magnetic field could be reduced because the Cu-Sn layer was paramagnetic, i.e., nonmagnetic.

• 센서학회지
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• 제33권2호
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• pp.105-111
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• 2024

In this study, the H₂S gas sensing characteristics were evaluated using surface-modified SnO₂ microparticles by tip sonication. The surface-modified SnO₂ microparticles were synthesized using the following sequential process. First, bare SnO₂ microparticles were synthesized via a hydrothermal method. Then, the surfaces of bare SnO₂ microparticles were modified with Ti nanoparticles during tip sonication. The sensing characteristics of SnO₂ microparticles modified with Ti were systematically investigated in the range of 100-300℃, compared with the bare SnO₂ microparticles. In this study, we discuss in detail the improved H₂S sensing characteristics of SnO₂ microparticles via Ti nanoparticle modification.

• Nano
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• 제13권11호
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• pp.1850130.1-1850130.12
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• 2018

A novel strontium titanate/binary metal sulfide ($SrTiO_3/SnCoS_4$) heterostructure was synthesized by a simple two-step hydrothermal method. The visible-light-driven photocatalytic performance of $SrTiO_3/SnCoS_4$ composites was evaluated in the degradation of methyl orange (MO) under visible light irradiation. The photocatalytic performance of $SrTiO_3/SnCoS_4-5%$ is much higher than that of pure $SrTiO_3$, $SnCoS_4$, $SrTiO_3/SnS_2$ and $SrTiO_3/CoS_2$. The $SrTiO_3/SnCoS_4$ composite material with 5 wt.% of $SnCoS_4$ showed the highest photocatalytic efficiency for MO degradation, and the degradation rate could reach 95% after 140 min irradiation time. The enhanced photocatalytic activity was ascribed to not only the improvement of visible light absorption efficiency, but also the construction of a heterostructure which make it possible to effectively separate photoexcited electrons and holes in the two-phase interface.

• 센서학회지
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• 제15권5호
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• pp.309-316
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• 2006

The $SnO_{2}$ thin film sensors were fabricated by a thermal oxidation method. $SnO_{2}$ thin film sensors were treated in $N_{2}$ atmosphere. The sensors with $O_{2}$ treatment after $N_{2}$ treatment showed 70 % sensitivity for 1 ppm $H_{2}S$ gas, which is higher than the sensors with only $O_{2}$ treatment. The Ni metal was evaporated on Sn thin film on the $Al_{2}O_{3}$ substrate. And the sensor was heated to grow the Sn nanowire in the tube furnace with $N_{2}$ atmosphere. Sn nanowire was thermally oxidized in $O_{2}$ environments. The sensitivity of $SnO_{2}$ nanowire sensor was measured at 500 ppb $H_{2}S$ gas. The selectivity of $SnO_{2}$ nanowire sensor compared with thin film and thick film $SnO_{2}$ was measured for $H_{2}S$, CO, and $NH_{3}$ in this study.

• Journal of Welding and Joining
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• 제20권2호
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• pp.77-81
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• 2002

Many kinds of Pb-free solder have been investigated because of the environmental concerns. Sn-Ag-Cu system is well blown as most competitive Pb-free solder. However, since Sn-Ag-Cu system has relatively high melting point compared to Sn-Pb eutectic, it may a limitation, the some application. In this study, Bi and In contained solder of $Sn_3Ag_8Bi_5In$ which has relatively lower melting point, $188~204^{\circ}C$, was investigated. $Sn_3Ag_8Bi_5In$ solder ball of $500\mu\textrm{m}$ diameter was set on the Ni/Cu/Cr-UBM and reflow soldered in the range of $220~240^{\circ}C$ for 5~15s. The maximum shear strength of the solder ball was around 170mN by reflowing at $240^{\circ}C$ for 10s. Intermetallic compound formed on the UBM of Si-wafer was analysed by SEM(scanning electron microscope) and XRD(X-ray diffractometer).

• 한국자기학회지
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• 제25권5호
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• pp.156-161
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• 2015

이 연구에서는 X-선 광전자분광법(X-ray photoemission spectroscopy: XPS)을 이용하여 염료감응 태양전지의 전극용 후보 물질에 속하는 $ZnSnO_3$와 $Zn_2SnO_4$의 전자 구조를 연구하였다. 제조된 시료들에 대한 X-선 회절 측정에 의하면 $ZnSnO_3$와 $Zn_2SnO_4$ 시료는 각각 단일상의 ilmenite(IL) 구조와 역스피넬(inverse spinel) 구조를 가지고 있음을 알 수 있었다. Zn 2p와 Sn 3d 내각준위 XPS 측정으로부터 $ZnSnO_3$와 $Zn_2SnO_4$ 두 시료 모두에서 Zn 이온은 2가 (Zn 2+) 상태이며, Sn 이온은 4가 (Sn 4+) 상태임을 알 수 있었다. 한편 얕은 내각준위 XPS 스펙트럼의 측정에서는 $ZnSnO_3$의 Sn 4d와 Zn 3d 내각 준위들의 결합에너지가 $Zn_2SnO_4$에서 보다 다소 작게 관찰되었다. 이 연구로부터 $ZnSnO_3$와 $Zn_2SnO_4$에서의 각 이온의 원자가 상태와 화학적 결합 상태에 대한 정보를 얻을 수 있었다.

• Journal of Electrochemical Science and Technology
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• 제8권3호
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• pp.206-214
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• 2017

SnS films have been prepared by electrodeposition technique onto Cu and ITO substrates using acidic solutions containing tin chloride and sodium thiosulfate with sodium citrate as an additive. The effects of sodium citrate on the electrochemical behavior of electrolyte bath containing tin chloride and sodium thiosulfate were investigated by cyclic voltammetry and chronoamperometry techniques. Deposited films were characterized by XRD, FTIR, SEM, optical, photoelectrochemical, and electrical measurements. XRD data showed that deposited SnS with sodium citrate on both substrates were polycrystalline with orthorhombic structures and preferential orientations along (111) directions. However, SnS films with sodium citrate on Cu substrate exhibited a good crystalline structure if compared with that deposited on ITO substrates. FTIR results confirmed the presence of SnS films at peaks 1384 and $560cm^{-1}$. SEM images revealed that SnS with sodium citrate on Cu substrate are well covered with a smooth and uniform surface morphology than deposited on ITO substrate. The direct band gap of the films is about 1.3 eV. p-type semiconductor conduction of SnS was confirmed by photoelectrochemical and Hall Effect measurements. Electrical properties of SnS films showed a low electrical resistivity of $30{\Omega}cm$, carrier concentration of $2.6{\times}10^{15}cm^{-3}$ and mobility of $80cm^2V^{-1}s^{-1}$.

• 한국전기전자재료학회논문지
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• 제29권7호
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• pp.445-448
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• 2016

Transparent UV photodetector was achieved by using wide bandgap metal oxide materials. In order to realize transparent heterojunction UV photodetector, n-type ZnO and p-type NiO metal oxide materials were employed. High light-absorbing SnS layer was inserted into the n-ZnO and p-NiO layers. High-performing UV photodetector was realized by ZnO/SnS/NiO/ITO structures to provide extremely fast response times (Fall time: $7{\mu}s$ and rise time: $13{\mu}s$) and high rectifying ratio. The use of functional SnS-embedded photodetector would provide a route for high functional photoelectric devices.

• 한국전기전자재료학회논문지
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• 제24권7호
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• pp.589-593
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• 2011

[ $SnO_2$ ]nano powders were prepared by solution reduction method using tin chloride($SnCl_2{\cdot}2H_2O$), hydrazine($N_2H_4$) and NaOH. The $SnO_2$ thick films for gas sensors were fabricated by screen printing method on alumina substrates and annealed at $300^{\circ}C$ in air, respectively. XRD patterns of the $SnO_2$ nano powders showed the tetragonal structure with (110) dominant orientation. The particle size of $SnO_2$ nano powders at the ratio of $SnCl_2:N_2H_4$+NaOH= 1:6 was about 60 nm. The sensing characteristics were investigated by measuring the electrical resistance of each sensor in a test box. Sensitivity of $SnO_2$ gas sensor to 5 ppm $CH_4$gas and 5 ppm $CH_3CH_2CH_3$ gas was investigated for various $SnCl_2:N_2H_4$+NaOH proportion. The highest sensitivity to $CH_4$ gas and $CH_3CH_2CH_3$ gas of $SnO_2$ sensors was observed at the $SnCl_2:N_2H_4$+NaOH= 1:8 and $SnCl_2:N_2H_4$+NaOH= 1:6, respectively. Response and recovery times of $SnO_2$ gas sensors prepared by $SnCl_2:N_2H_4$+NaOH= 1:6 was about 40 s and 30 s, respectively.