• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.323-323
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• 2007

Influence of $La_2O_3$ addition to $CaO-B_2O_3$-based glass on the water leaching resistance of the glass was first investigated. The optimized $La_2O_3-CaO-B_2O_3$(LCB) glass was ball milled for varying time, followed by mixing with $Al_2O_3$ crystalline phase to form $Al_2O_3$-LCB glass composites at $875^{\circ}C$ for 1h. Microwave dielectric properties of the composites were investigated as a function of the ball milling time of the LCB glass. Dielectric constant and quality factor of the composites were 6.31 and 13856 GHz, respectively, when the LCB glass was ball milled for 2h prior to mixing with $Al_2O_3$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.324-324
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• 2007

Influence of $La_2O_3$ addition to $ZnO-B_2O_3$-based glass on the water leaching resistance of the glass was first investigated. The optimized $La_2O_3-ZnO-B_2O_3$ (LZB) glass was ball milled for varying time, followed by mixing with $Al_2O_3$ crystalline phase to form $Al_2O_3$-LZB glass composites at $875^{\circ}C$ for lh. Microwave dielectric properties of the composites were investigated as a function of the ball milling time of the LZB glass. Dielectric constant and quality factor of the composites were 6.01 and 11676 GHz, respectively, when the LZB glass was ball milled for 2h prior to mixing with $Al_2O_3$.

• 대한의용생체공학회:의공학회지
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• 제14권4호
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• pp.333-340
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• 1993

The high biocompatibility of titanium is connected with the high corrosion resistance of the surface oxide, its high dielectric constant, and some other specific biochemical properties of the oxide. The corrosion resistance of titanium can be improved with the formation of passive film by anodic oxidation. In other to characterize the titantium oxlde film formed by anodic oxidation, titanium plates were anodized in 0.5M $H_3SO_4$ electrolyte at voltages between 5V and 100v. The oxide film was examined by an X-Ray Diffractometer(XRD) and a Scanning Electron Microscope(SEM). In addition, the corrosion resistance of oxide film was tested by dipping in physiological NaCl,5% HCI,5% $H_3PO_4$ and its biocompatability was evaluated by the fibroblast-like cell culture. The results obtained are as follows : 1. The thickness of surface oxide and micropore are increased with the increase of electrode potential and formed deeply along the grain boundary. 2. The solubilities of titanium in electrolyte solution shows that the anodized titanium has more corrosion resistance than the untreated pure titanium. 3. The biocomatibility of anodized titanium is superior to untreated pure titanium.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.865-868
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• 2000

It was examined that the relationship between microstructures, electrical properties and crystal structure of (1-x)CaMnO$_3$-xCaTiO$_3$solid solution system which was made by mixing a semiconducting material CaMnO$_3$of low resistance and a dielectric material CaTiO$_3$of high resistance with variable ratios (x=0, 0.1, 0.3, 0.5, 0.7, 0.9, 1.0). As the CaTiO$_3$increased, the resistance, B constant and lattice constant were increased, but the grain size was decreased. On particular, above 50wt% of CaTiO$_3$, the resistance at 2 5$^{\circ}C$ was rapidly increased due to the correlation in connectivity of the lattices between the conductive Mn$^{+4}$ octahedron and the insulative Ti$^{+4}$ octahedron.ron.

• 조명전기설비학회논문지
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• 제24권1호
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• pp.98-104
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• 2010

고주파수성분을 포함하는 뇌격전류나 또는 고장전류에 대한 접지시스템의 성능을 평가하기 위해 접지저항보다는 접지임피던스에 대한 고려가 필요하다. 접지임피던스를 평가하기 위해서는 토양의 저항률과 비유전율의 주파수의존성이 규명되어야 한다. 본 논문은 3가지 다른 토양에 대하여 수분함유량에 따른 저항률과 비유전율의 주파수의존성을 나타낸다. 결론적으로 토양의 저항률은 수분함유량이 증가함에 따라서 작아지게 되고, 1[MHz]보다 낮은 주파수에서 거의 변화하지 않으며 1[MHz]이상의 주파수에서는 감소한다. 반면에 비유전율은 1[MHz]이하의 주파수에서 매우 급격하게 감소하며, 1[MHz]이상의 주파수에서는 거의 변화하지 않는 것으로 나타났다. 본 실험 결과로 부터 낙뢰 또는 개폐서지에 대한 보호를 목적으로하는 접지시스템의 설계시 토양의 저항률과 비유전율을 고려하는 것이 바람직한 것으로 밝혀졌다.

• 한국재료학회지
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• 제3권1호
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• pp.12-18
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• 1993

단결정 실리콘위에 스퍼터법으로 증착된 티타니움막을 급속가열로에서 고상반응에 의해 형성시킨 면저항 1.2 ohm/sq. 내외의 TiS$i_2$ 박막에 있어서 열안정성을 상부절연막의 유무 및 종류에 따라 조사하였다. 상부절연막은 상압 CVD로 증착한 USG(Undoped Silicate Glass, Si$i_2$) 막과 플라즈마 CVD법으로 증착한 PE-SiN(S$i_3$$N_4$)막을 사용했다. 열안정성 평가는 90$0^{\circ}C$에서 시간을 달리하여 TiS$i_2$막, PE-SiN막, USG막의 스트레스는 각각 1.3${\times}{10^{9}}$, 1.25 ${\times}{10^{10}}$, 2.26 ${\times}{10^{10}}$ dyne/c$m^2$의 인장응력을 나타내었다. 응집현상은 TiS$i_2$의 응집현상은 Nabarro-Herring 마이크로 크리프에 의한 원자의 확산관점에서 검토되었다.

• 대한전자공학회논문지
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• 제22권2호
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• pp.90-96
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• 1985

PECVD장비를 사용하여 PSG를 증착하고 막의 유전 및 보호막 특성을 조사하였다. X-선 형광분석으로 PSG내의 인 농도를 분석한 결과 약 8m/o에서 포화되었다. 인 함량에 대한 PSC의 적외선 홉수율, 식각속도 및 시트저항등의 변화도 비교하였다. APCVD와 PECV각에 대한 유전특성, 스텝 커버리지, 크랙저항과 게터링효과를 검토하였다. PECVD산화막은 비중 2.4g/㎤, 굴절율 1.53, 항복전장 11-13MV/cm의 값을 가졌고 크랙저항도 APCVD산화막 보다 우수하였다 2m/o의 인을 포함하는 PECVD PSG의 경우 양호한 스텝 커버리지와 게터링효과를 보였다. 공정변수에 대한 일련의 실험을 통하여 PECVD PSC 공정으로 보다 개선된 특성의 보초막을 얻을 수 있었다.

• 한국초전도ㆍ저온공학회논문지
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• 제7권1호
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• pp.42-46
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• 2005

The resistive type high temperature superconducting fault current limiter (HTSFCL) limits the fault current using the resistance generated by fault current. The generated resistance by fault current makes large pulse power which makes the operation of HTSFCL unstable. So, the cryogenic cooling system of the resistive type HTSFCL must diffuse and eliminate the pulse energy very quickly. Although the best way is to make wide direct contact area between HTS winding and coolant as much as possible, HTS winding also needs the impregnation layer which fixes and protects it from electromagnetic force. This paper deals with the thermal conductivity and dielectric strength of some epoxy compounds for the impregnation of high temperature superconducting (HTS) winding in liquid nitrogen. The measured data can be used in the optimal design of impregnation for HTS winding. Aluminar filling increased the thermal conductivity of epoxy compounds. Hardener also affected the thermal and electric characteristic of epoxy compounds.

• 한국전기전자재료학회논문지
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• 제16권12호
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• pp.1080-1086
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• 2003

Effects of E$_2$O$_3$. HO$_2$O$_3$ and Dy$_2$O$_3$ addition on dielectric properties of non-reducible BaTiO$_3$ based X7R dielectrics with Ni electrode have been studied in a reduced atmosphere. As the content of rare-earth with E$_2$O$_3$. HO$_2$O$_3$, Dy$_2$O$_3$ was less than 3wt%, The TCC(Temperature Capacitance Change) and insulation resistance characteristics were improved by compensate the oxygen vacancies due to occupy either the Ba or Ti site. We developed the composition of X7R (EIA standard) for higher capacitance MLCC which had high reliability electric properties by the addition of Er ion into BaTiO$_3$ + MgO + Y2O$_3$ + MnO + (Ba$\sub$0.4/Ca$\sub$0.6/)SiO$_3$ composition.

• Transactions on Electrical and Electronic Materials
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• 제12권3호
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• pp.110-114
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• 2011

Polymeric films of high chemical stability and mechanical strength covered with a thin metallic film have been extensively used in various fields as electric and electronic materials. In this study, we have chosen polypropylene (PP) as the polymer due to its outstanding chemical resistance and good creep resistance. We coated thin nickel film on PP films by the electroless plating process. The surfaces of PP films were pre-treated and modified to increase the adhesion strength of metal layer on PP films, prior to the plating process, by an environment-friendly process with atmospheric plasma generated using dielectric barrier discharges in air. The surface morphologies of the PP films were observed before and after the surface modification process using a scanning electron microscope (SEM). The static contact angles were measured with deionized water droplets. The cross-sectional images of the PP films coated with thin metal film were taken with SEM to see the combined state between metallic and PP films. The adhesion strength of the metallic thin films on the PP films was confirmed by the thermal shock test and the cross-cutting and peel test. In conclusion, we made a composite material of metallic and polymeric films of high adhesion strength.