• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.4
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• pp.367-373
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• 2007

[ $In_2O_3-ZnO(IZO)$ ] and $In_2O_3-ZnO-SnO_2(IZTO)$ thin films were prepared on EAGLE 2000 glass webs in a Ar gas by RF-Magnetron sputtering. Electrical resistivity and optical transmittance of the films were investigated. IZO, IZTO film showed excellent optical transmittance of 85 % at the visible $400{\sim}$780 nm wavelength. Electrical properties of IZO film have $6.50{\times}10^{-4}{\Omega}cm$ (95 $In_2O_3$ : 5 ZnO wt.%) and $5.20{\times}10^{-4}{\Omega}cm$ (90 : 10 wt.%), IZTO film have $8.00{\times}10^{-4}{\Omega}cm$ (90 $In_2O_3$ : 3 ZnO : 7 $SnO_2$ wt.%) and $6.50{\times}10^{-4}{\Omega}cm$ (90 : 7 : 3 wt.%). Substitution of SnO to ZnO in ITO films showed slightly lower electrical conductivity than ITO film but showed similar optical transmittance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.12
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• pp.797-802
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• 2014

In this study, in order to develop the capacitor composition ceramics with the good dielectric properties, $(Ba_{1-x}Ca_x)(Ti_{0.85}Zr_{0.12}Sn_{0.03})O_3$ (abbreviated as BCTZ) ceramics were prepared by the conventional solid-state reaction method. The effects of Ca substitution on the microstructure and dielectric properties was investigated. The X-ray diffraction patterns demonstrated that all the specimens showed perovskite phase, and secondary phases are indicated in the measurement range of X-ray diffraction. Also, all the specimens indicated an rhombohedron phase structure. It was identified from the X-ray diffraction patterns that the secondary phase formed in grain boundaries and then decreased the dielectric properties. For all the specimens, observed one peak was tetragonal cubic phase transition temperature($T_c$), which is located in the vicinity of room temperature.

• Nuclear Engineering and Technology
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• v.5 no.1
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• pp.26-29
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• 1973

Halongen exchange reactions of phenylethyl bromides have been studied in acetone at 25$^{\circ}$and 35$^{\circ}C$. Results show that the reaction proceeds by a typical S$_{N}$2 path, and steric crowding effect in 1-phenylethyl bromide gives large variation in the activation parameters for chloride exchange.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2005.09a
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• pp.63-67
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• 2005

Pentacene channel OTFT(organic thin film transistor)을 SiOC 절연박막 위에서 film by thermal evaporation 방법을 이용하여 성장시켰다. CVD 방법으로 증착시킨 SiOC 절연막은 조성비에 따라 특성이 달라지므로 절연막 위에서의 펜타센의 화학적 반응을 조사하기 위해서 inorganic-type인 $O_2/(BTMSM\;+\;O_2)$ = 0.5의 비율을 갖는 SiOC 박막을 사용하였다. 팬타센 분자의 말단에서 SiOC 표면에서 Diels-Alder 반응에 의한 이중결합이 깨어지면서 안정된 성장을 하지만 온도가 높아감에 따라 표면에서의 $SN_2$(bimolecular nucleophilic substitution) 반응과 연쇄적인 화학반응에 의해 팬타센의 성장을 방해하는 것으로 나타났다.

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.127.1-127.1
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• 2008

• 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%.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.3
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• pp.127-133
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• 2012

To achieve low-cost and high-efficiency of thin-film solar cells applications, the sol-gel method that can be coated on a large area substrate, obtain homogeneous thin films of high purity was used. We studied structural and optical characteristics versus annealing temperature of $Cu_2ZnSnS_4$ which has kesterite structure by substitution low-cost sulfur (S) instead of high-cost selenium (Se). By analyzing XRD patterns, main peak was observed at $2{\theta}=28.5^{\circ}$ when Zn/Sn ratio is 0.8/1.2. And when we observed kesterite structure which has orientation of (112) direction, the more annealing temperature increase the bigger strength of (112) direction is. $Cu_2ZnSnS_4$ thin film showed characteristics of kesterite structure at $550^{\circ}C$. And when we calculated lattice constant, a = 5.5047 and $c=11.014{\AA}$ as same JCPDS (Joint Committee on Powder Standards) data measured. We measured optical transmittance to analyze optical characteristics. Optical transmittance was lower than 65 % at visible ray (${\lambda}=380{\sim}770nm$).

• Journal of the Korean Ceramic Society
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• v.28 no.11
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• pp.897-907
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• 1991

This study was conducted to research the formation and the color development of CoO-ZnO-Fe2O3-TiO2-SnO2 system for the purpose of synthesizing the spinel pigments which are stable at high temperature. After preparing CoO-ZnO-Fe2O3, in which CoO causes the color, as a basic composition, $\chi$CoO.(1-$\chi$)ZnO.Fe2O3 system, $\chi$CoO.(1-$\chi$)ZnO.TiO2 system and $\chi$CoO.(1-$\chi$)ZnO.SnO2 system were prepared with $\chi$=0, 0.2, 0.5, 0.7, 1.0 mole ratio respectively. The manufacturing was carried out at 128$0^{\circ}C$ for 90 minutes. These specimens were analyzed by the reflectance measurement and the X-ray diffraction analysis and the results were summarized as follows: 1. All of the specimens formed the spinel structure and were colored with stable yellow or blue. 2. As the content of CoO and Fe2O3 in the specimens being increased, the reflectance of each specimen was measured becoming lower and the colors were changed from yellow to greyish blue and from blue to dark blue. 3. As the substituting amount of Co2+ ion for Zn2+ ion in $\chi$CoO-ZnO-TiO2-SnO2 system being increased, the colors were changed from blue to greyish blue. The colors were changed from yellow to grayish green owing to the tetrahedral Co2+ ions being increased, the octahedral Co2+ ions being decreased with increasing the amount of Sn4+ ions. 4. CoO-ZnO-Fe2O3-TiO2-SnO2 system, in which Zn2+ was substituted with Co2+ and Fe3+ was substituted with Ti4+ and Sn4+, easily formed the spinel structure without regard to the amount of substitution or the ion owing to the selectivity of the coordination number: 4 of Zn2+, 4 of Co2+, 6 of Fe3+ or 6 of Ti4+ and Sn4+.

• Electrical & Electronic Materials
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• v.11 no.11
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• pp.9-17
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• 1998

The dependence of the ionic conductivity on the B-site ion substitution in (Li0.5La0.5)Ti1-xMxO3 (M=Sn, Zr, Mn, Ge) system has been studied. Same valence state and various electronic configuration and ionic radius of Sn4+, Zr4+, Mn4+ and Ge4+(4d10(0.69$\AA$), 4p6(0.72$\AA$), 3d10(0.54$\AA$) and 3d3(0.54$\AA$), respectively) induced the various crystallographic variaton with substitutions. So it was possibleto investigate the crystallographic factor which influence the ionic conduction by observing the dependence of the conductivity on the crystallographic factor which influence the ionic conduction by observing the dependence of the conductivity on the crystallographic variations. We found that the conductivity increased with decreasing the radii of B-site ions or vice versa and octahedron distortion disturb the ion conduction. The reason for this reciprocal proportion of conductivity on the radius of B-site ions has been examined on the base of the interatomic bond strength change due to the cation substitutions. The results were good in agreement with the experimental results. Therefore it could be concluded that the interatomic bond strength change due to the cation substitutions may be the one of major factors influencing the lithium ion conductivity in perovskite(Li0.5La0.5) TiO3system.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.4
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• pp.169-175
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• 2014

Digital ink-jet printing system has many advantages such as fast and fine printing of various images, high efficiency and low cost process. Generally digital ink-jet printing requires ceramic pigments of cyan, magenta, yellow and black with thermal and glaze stability above $1000^{\circ}C$ for the application of porcelain product design. In this study, pink-red colored $CaO-SnO_2-Cr_2O_3-SiO_2$ pigment was synthesized using solid state reaction. The synthesis conditions of $Ca(Cr,Sn)SiO_5$ pigment such as annealing temperature, amount of mineralizer and non-stoichiometric composition were optimized. Crystal structure and morphology of the obtained $Ca(Cr,Sn)SiO_5$ pigment were analyzed using XRD, SEM, PSA, FT-IR and effect of Cr substitution on the pigment color was analyzed using Uv-vis. spectrophotometer and CIE $L^*a^*b^*$ measurement.