• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1110_1111
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• 2009

최근 광 캐패시터 전극 분야는 고효율과 넓은 응용분야로 인해 주목 받고 있다. 본 연구에서는 carbon, 활성 carbon을 사용하여 캐패시터샘플을 제작 하였고 간단한 샌드위치 구조에 각각의 캐패시터 전극은 $20{\times}15nm$의 셀을 사용하였다. 각 셀들은 제작방법에는 졸겔법이 사용되었다. 각 셀들의 수분 및 기타물질의 제거를 위해 $120^{\circ}C$에서 1시간동안 건조시켰고 $500^{\circ}C$에서 2시간동안 소결처리 하였다. 소결처리로 인한 carbon의 특성변화를 알아보기 위해 XRD분석을 실시하였다. 본 연구에서는 캐패시터의 특성을 파악하기 위해 임피던스 특성을 분석하였고 그에 따른 부수적인 결과들을 기술하였다. active carbon을 사용한 캐패시터의 충방전 특성을 측정하였고 최종적으로 평균 두께 $32{\mu}m$, 입자사이즈 $1\sim4.5{\mu}m$의 캐패시터전극용 샘플($20{\times}15nm$)을 제작하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.377-380
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• 2001

The BST thin films to composite (Ba$\sub$x/Sr$\sub$l-x/)TiO$_3$ using sol-gel method were fabricated on Pt/Ti/SiO$_2$/Si substrate. The thin film capacitor to be ferroelectric materials was investigated by structural and electrical properties. BST solution was composited by moi ratio, and then spin-coated (from 3 times to 5 times coating on Pt/SiO$_2$/Si substrate. Thickness of BST ceramics thin films are about 2600∼2800[${\AA}$] in 3 times deposition. The property of leakage current was stable when the applied voltage was 3[V]. Leakage current of 3 times coated BST thin film was 10$\^$-9/∼10$\^$-11/[A] at 0∼3[V].

• 한국세라믹학회지
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• 제28권7호
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• pp.503-508
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• 1991

High pure and fine mullite powders were synthesized from Al-secbutoxide[Al(OC4H9)3] and TEOS[Si(OC2H5)4] (SiO2/Al2O3=2/3 mole). Sol-Gel process by partial hydrolysis technique, as it were, first, TEOS was partially hydrolysized and then mixed with Al-secbutoxide for complete hydrolysis was used. The mullite precursor was synthesized within 30 hrs, which was reduced about a half of synthetic time in comparison with the other's study. Al-Si spinel was formed at 980℃ and mullite crystal was formed at 1200℃. Mullite powders synthesized in this study was spherical type like those of the other studies and particle sizes were very fine. Also mullite powders calcined at 1,600℃ had a stoichiometric composition (3Al2O3·2SiO2) and lattice constants were coincided with known theoretical values.

• 한국세라믹학회지
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• 제28권9호
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• pp.705-711
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• 1991

Alumina precursor sol was obtained by the reaction of Al(OC4H9)3 and acetylacetone in the solvent followed by the partial hydrolysis. This sol was measured by viscosity and the effect of pH. The powders obtained from this sol were calcined at the various temperatures. The transition of crystals and crystal state were investigated at the various temperatures. The powders dried at 90$^{\circ}C$ showed amorphous and ${\gamma}$-Al2O3 at 900$^{\circ}C$, ${\alpha}$-Al2O3 mono-phase at 1050$^{\circ}C$ respectively. As a result of Al27-MASNMR analysis, amorphous and ${\alpha}$-Al2O3 powders showed 6-coordinated Al, ${\gamma}$-Al2O3 4-coordinated Al respectively.

• 한국세라믹학회지
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• 제29권1호
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• pp.48-52
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• 1992

Indium tin oxide (ITO) layers are of considerable interest on account of the combination of properties they provide high electrical conductivity, high infrared reflection with high solar energy transmission, high transmission in the visible range. We are concerned about the variation of the spectral transmittances and sheet resistances as the thickness of SiO2-ZrO2 barrier layer and ITO layers and heat treating conditions are changed. Transmittances and reflectivities were studied by measuring UV-VIS-NIR-, FT-IR spectroscopy. ITO films are crack free, homogeneous and of polycrystalline cubic structure. The microstructure of good ITO films shows a narrow grain size distribution and mean value of 100 nm. The selectivity of absorbing properties is improved by increasing the thickness of ITO films. The increase of sheet resistance of ITO films are due to the increase in the reaction between films and glass substrate.

• 한국세라믹학회지
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• 제32권1호
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• pp.17-24
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• 1995

The TEA complex polymeric sol was prepared by the alkoxide sol-gel method. The purpsoe of this experiment was to vefity the particle shape in the sol from the investigation of the rheological properties. TEA retarded hydrolysis rate by the reaction with alkoxide enough to make a stable transparent sol in the wide range of composition. From the results of the viscosity change with time, the optimum mole ratio for spinning was selected as 0.5 mole of TEA, 3 mole of H2O and the optimum viscosity was 104 cPs. The rheological behavior of the sol showed that the particle shape in the sol was linear, which was adequate for fiber drawing.

• 대한전자공학회논문지
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• 제27권10호
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• pp.101-105
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• 1990

약 $900^{\circ}C$에서 합성된 코디에라이트의 합성 방법인 졸겔방법은 구리와 세라믹간의 상호 열처리를 가능하게 해준다. 구리와 코디에라이트 기판과의 강한 결합은 eutectic bonding 기술로 얻어질 수 있다. 구리와 코디에라이트의 접촉면에서 미시적 특성을 STEM을 이용하여 연구하였는데 구리의 확산은 강한 화학적, 구조적 변화와 함께 접촉면 영역에서 이루어지고 있다. 비록 이들 접촉면이 강한 접촉력을 가지고 있지만 접촉면에서 구리화합물의 형성에 대한 명백한 입증을 얻어내지는 못하였다.

• 한국세라믹학회지
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• 제34권1호
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• pp.37-44
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• 1997

졸겔법중 딥코팅법을 이용하여 조성비 2Fe/Ba=5.25 졸로부터 바륨페라이트 박막을 제조하였다. 졸의 겔화과정은 4단계로 구분할 수 있으며, 8$0^{\circ}C$에서 90분간 반응시켜 제조한 졸이 코팅용 졸로서 가장 적합한 특성을 나타내었다. 박막층에 형성된 침상 형태의 입자들은 기판에 수평 하게 위치하고 있었으며, 박막 두께가 증가함에 따라 그 경향은 증가하였다. 침상형 입자의 자화용이축 방향은 장축 방향이었다.

• 한국세라믹학회지
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• 제28권11호
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• pp.859-864
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• 1991

High quality lead titanate thin films were fabricated by spin coating on a silicon substrate. The resulting dried gel layers were uniform in thickness through 2$\times$2 $\textrm{cm}^2$ area, and polycrystalline perovskite structures developed almost crack free with a heat treatment above 50$0^{\circ}C$ in films with thickness above 360 nm. Metastable pyrochlore structures were observed in films with thickness of 160 nm when heat treated at 500 and $600^{\circ}C$, but these structure did not appear in films with thickness of 360 nm. The thickness dependence in crystal structure of films was studied. by varying the substrate condition and analyzing the interface between the film and substrate. In native oxide films on silicon stbstrates, amorphous dried gel layers were heterogeneously nucleated. Metastable cubic pyrochlore structure could be crystallized in amorphous native oxide.

• 대한기계학회논문집A
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• 제33권3호
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• pp.237-242
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• 2009

MEMS catalytic combustors were fabricated to use in micro-power sources as a heat source. The combustor was fabricated by photolithography and anisotropic wet etching of photosensitive glass wafers. Two different catalyst loading methods were used to complete the fabrication of the combustors. For thin film type, the $Al_2O_3$ was washcoated on the surface of the combustion chamber as a catalyst support, and for packed-bed type, ceramic foam was inserted after Pt was coated. The volume of the combustors was 1.8 $cm^3$ and 16W of heat was generated using the fabricated combustors with hydrogen. The energy density of combustor was about 8.9 W/$cm^3$.