• Proceedings of the Materials Research Society of Korea Conference
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• 2005.05a
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• pp.303-303
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• 2005

• Journal of the Microelectronics and Packaging Society
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• v.2 no.1
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• pp.35-48
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• 1995

마이크로회로내에서 티탄산바륨 중 바륨의 일부가 납으로 치환됨에 따른 전기적 특 성의 변화를 확인하기 위하여 MOD(금속유기화합물 분해법)공정에 의 barum 2-ethylhexanoate, barium neodecanoate, lead 2-ethylhexanoate 및 titanium dimethoxy 야 -2-ethylhexanoate 와 같은 MOC(금속 유기화합물) 들을 합성하고 공통 용매에 대한 용해 도를 시험하였다. 그 결과 barium 2-ethylhexanoate 만 p-xylene에 대한 용해도가 낮았으며 그 외의 다른 MOC들은 모두 p-xylene 단일 용매에 매우 잘 용해되었다. 바륨의 일부가 납 으로 치환된 티탄산 납바륨 박막은 MOC 혼합용액을 ITO/glass, Pt/SiO2/Si 및 Pt/Ti/SiO2/Si 웨이퍼 기판 위에 spin coating 하고 소성하여 얻었다. 이와 같이 얻어진 박막 의 전기적 특성을 측정하고 그 결과를 비교 고찰하였다.

• Journal of Industrial Technology
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• v.21 no.B
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• pp.133-139
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• 2001

Generally $PbTiO_3$ is manufactured in a form of thin films which is useful for the application of infrared sensors and non-volatile memory devices. Moreover $PbTiO_3$ has a characteristic of adsorption for organic acid as well as electronic property. Organic acid adsorption properties of $PbTiO_3$ powder prepared by sol-gel method was compared with the powder purchased from Aldrich Co. Crystallization and particle size of $PbTiO_3$ are influenced by process variables, such as dilution of sol solution, catalysis, calcination temperature, calcination time, etc. As the size of $PbTiO_3$ power decreased until several nanometers, adsorption of acetic acid and formic acid was increased 1.5-fold and 1.2-fold respectively.

• Applied Chemistry for Engineering
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• v.5 no.1
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• pp.160-175
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• 1994

Fibrous potassium hexatitanate whisker with the size of $ID=0.5{\sim}1{\mu}m$ and length=$100{\sim}1000{\mu}m$ (aspect ratio=100~1000) was produced through the reaction between titanium dioxide and potassium carbonate using the slow-cooling calcination followed by water leaching treatment. The optimum condition for the production of fibrous potassium titanate was calcination temperature of $1100^{\circ}C$ for 5hrs, $TiO_2$ mole ratlo to $K_2CO_3$ of 4.5 and slow-cooling rate of $0.5^{\circ}C/min$ to $860^{\circ}C$. Fibrous crystal are grown by the association between the solid potassium titanate and liquid phase during the slow-cooling process. The Proper water leaching condition for removing of K component was leaching time of 10hrs in boiling water. Pressurizing of the mixture of $K_2CO_3$ and $TiO_2$ to be calcinated became effective on the growth of fibrous crystal.

• The Journal of Natural Sciences
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• v.1
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• pp.47-59
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• 1987

The thermal decomposition mechanism of BaTiO($$C_2$$O_4$)_2$ $4H_2$O has been investigated employing TG, DTG, and DTA techniques. The intermediate compounds and the gaseous products of decomposition were examined by IR spectrometer and X-ray analyser. The decomposition proceeds through five steps. The first step which is the dehydration of the tetrahydrate is followed by the decomposition of oxalate groups. During the second decomposition, half a mole of carbon monoxide is evolved. The oxalate groups are completely destroyed in the range $260~460^{\circ}C$, resulting in the formation of a carbonate which retains free carbon dioxide in the matrix . the final decomposition of the carbonate takes place between $650~750^{\circ}C$ and yields $BaTiO_3$.

• Journal of the Korean Solar Energy Society
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• v.26 no.4
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• pp.55-61
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• 2006

Titanium oxide ($TiO_2$) films are deposited on the indium tin oxide (ITO) substrate in an $Ar/O_2$ atmosphere by using reactive RF (Radio Frequency) magnetron sputtering technique, and Electrochromic properties and durability of $TiO_2$ films deposited at different preparation conditions are investigated by using UV-VIS spectrophotometer and cyclic voltammetry Li+ interalation/deintercalation in $TiO_2$ films shows that the electrochromic properties and durability of as-deposited films strongly depend on gas pressure $TiO_2$ films formed in our sputtering conditions are found to remain transparent, irrespective of their Li+ ion contents. The optimum sputtering conditions for film as passive counter electrode in electrochromic devices are working pressure of $1.0\;{\times}\;10^{-2}\;torr$ and oxygen flow raes of $10{\sim}15\;sccm$, respectively.

• Journal of the Microelectronics and Packaging Society
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• v.1 no.2
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• pp.113-124
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• 1994

MOD법을 마이크로회로용 티탄산 바륨 콘덴서 박막형성에 적용하였다. Barium decanoate barium 2-ethylhexanoate titanium dimethoxy didecanoate 및 titanium dimethoxy di-2-ethylhexanoate와 같은 여러 가지 금속유기화합물들을 합성하고 동정한 다 음 공통용매에 대한 용해도를 시험하였다. 이금속유기화학물들 가운데 barium 2-ethylhexanoate와 titanium dimethoxy di-2-ethylhexanoate가 xylene-pyridine 혼합용매에 잘녹고 MOD법에 의한 BaTiO3 박막형성에 매우 안정한 조성을 이룸을 확인하였다. 이 조 성을 스핀코팅에 의하여 백금박과 실리콘 웨이퍼상에 금속유기화학물 막을 형성하고 최고 온도와 유지시간에 따라 소성하여 형성된 유전체 박막들의 전기전 특성을 측정하고 고찰하 였다.

• Journal of the Korean Ceramic Society
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• v.46 no.2
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• pp.137-145
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• 2009

A remarkable improvement of the productivity in barium titanate by slurry spray pyrolysis process was realized by supplying solid source slurry into the rector. The produced barium titanate powders showed uniform powder properties, and reproducibility with higher tetragonality in the range of 80$\sim$200 nm, case by case. The secondary calcination experiments of the as-prepared powders by spray pyrolysis revealed that the powders as-prepared over 700$^{\circ}C$ showed perfectly different behavior with the lower temperature's ones and the solid state reaction’s case. The result was discussed in terms of the reaction mechanism based on the activation energy analysis.

• Journal of the Korean Ceramic Society
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• v.36 no.7
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• pp.705-710
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• 1999

Stability and chemical durability for aqueous casting of BaTiO3 slurry with polycarylic acid(PAA) were studied. PAA was well chemisorbed on surface of BaTiO3 powder at neutral pH but did not chemically adsorbed at low pH. The amount of Ba dissolution in aqueous BaTiO3 slurry was abruptly increased at strong acid pH2 and also at high amount of PAA. Protection of Ba dissolution and stability of slurry could be obtained through the optimization of slurry conditions such as pH amount of surfactant and solid content.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.05a
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• pp.159-164
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• 1999

PTC (Positive Temperature Coefficient of Resistivity) 소자는 티탄산 바륨 (barium titanate) 계열의 페로브스카이트 (perovskite) 구조를 가지는 물질을 반도체화시켰을 때 큐리온도 부근에서 저항이 1,000배 이상 증가하는 물질을 가리킨다. 처음에는 BaTiO$_3$를 대상으로 12$0^{\circ}C$ 부근에서 발생하는 PTC 현상을 연구하였으나, BaTiO$_3$에 SrTiO$_3$, PbTiO$_3$를 첨가하면, 큐리온도를 낮출 수도 있고, 높일 수도 있어서 PTC 소자의 사용 영역이 넓어졌다. PTC 소자의 응용분야는 1) 천연색 텔레비젼 수상기와 모니터에 사용하는 degausser와 같은 스위칭 소자, 2) 냉장고용 컴프레서등에 사용되는 모터 기동용 소자, 3) 자동차 연료조기증발용 히타와 같은 세라믹 히타 소자로 크게 구분된다.(중략)