• 한국재료학회:학술대회논문집
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• 한국재료학회 1999년도 춘계학술발표강연 및 눈문개요집
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• pp.22-22
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• 1999

• 한국재료학회:학술대회논문집
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• 한국재료학회 2000년도 추계학술발표강연 및 논문개요집
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• pp.47-47
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• 2000

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.485-486
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• 2008

본 연구에서는 AC-PDP의 MgO박막의 특성을 개선하기 위하여 MgO재료에 $Al_2O_3$, CaO, BaO도핑을 하여 MgO 박막을 증착하였다. $Al_2O_3$, CaO, BaO가 도핑된 MgO 박막의 기초특성을 실험하였고 AC-PDP에서 면방전 구동시 휘도 및 효율의 개선과 대항방전 구동에서의 방전지연을 개선하였다. 특히, $Al_2O_3$ 200ppm, CaO 200ppm 일때 효율의 상승, CaO 200ppm, BaO 100ppm 일 때 방전늦음이 개선되었다. 이는 MgO재료에 $Al_2O_3$, CaO, BaO등 여러가지 재료의 도핑시에는 적정의 도핑함량이 있는 것으로 보여진다.

• 한국세라믹학회지
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• 제31권11호
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• pp.1299-1306
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• 1994

Effect of MgO content on microstructural evolution and microwave dielectric properties of Ba(Mg1/3Ta2/3)O3 system was investigated. MgO content was varied from 10 mol% deficiency to 10 mol% excess of stoichiometric composition, respectively. It was found that MgO-deficient specimen showed faster grain growth rate than stoichometric and MgO excess BMT system. Besides, sandwich type precipitates of Ba5Ta4O15 which was formed within the BMT grain, might lead to the anisotropic grain growth of BMT grain. On the contrary, in MgO excess specimen, BMT grain growth rate was retarded by precipitations of MgO phase in grain boundary. Besides, the Q values of MgO-deficient showed lower than MgO-excess due to precipitations of Ba5Ta4O15 within BMT grain.

• 한국세라믹학회지
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• 제35권12호
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• pp.1274-1279
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• 1998

The glass forming ability of the PbO-B2O3-TiO3-BaO system was investigated in relation to transitieon tem-peratures and the atomic ratio between constituents. Glass forming tendency was improved as the tem-peratures and the atomic ratio between constituents. Glass forming tendency was improved as the tem-perature differences between liquidus temperature and crystallization(or glass transition) temperature de-creased and the temperature difference between crystallization and glass transition temperature increases. The atomic ratio could be used as a criterion to deign glass systems. The interposition of B and Ba atoms between Pb and Ti atoms was one of important factors in glass formation.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2001년도 추계연구발표회 논문개요집
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• pp.48-49
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• 2001

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1997년도 Proceedings of the 13th KACG Technical Meeting `97 Industrial Crystallization Symposium(ICS)-Doosan Resort, Chunchon, October 30-31, 1997
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• pp.87-89
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• 1997

The BaTiO$_3$ fine powder was prepared by hydrthermal method using titanium tetrahydoxide (Ti(OH)$_4$) and barium dihydroxide (Ba(OH)$_2$.8$H_2O$) as raw materials. The fine powder was obtained at temperatures as low as 160 to 185$^{\circ}C$. The properties of the BaTiO$_3$ powder were studied as a function of various parameters (reaction temperature, reaction time, Ba/Ti=ratio, etc). The average particle size of the BaTiO$_3$ increased with increasing reaction temperature. After hydrothermal treatment at 17$0^{\circ}C$ for 8 h, the average particle size of the BaTiO$_3$ powder was about 30 nm and the particle size distribution was narrow.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2001년도 추계 학술발표회 논문집
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• pp.219-224
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• 2001

BaTiO$_3$분말을 barium hydroxide, meta titan acid를 이용하여 광화제 첨가 없이 열수처리에 의한 탈수(dehysration) 및 재경정화(recrystallization)과정으로 수열합성법에 의해 제조하였다. Autoclave 반응기를 이용한 실험의 경우, BaTiO$_3$분말을 생성하기 위한 최적 온도 및 반응시간은 각각 18$0^{\circ}C$, 4시간으로 확인되었으며, 이 때 생성된 BaTiO$_3$분말의 크기는 0.1~0.2$\mu\textrm{m}$로 입도분포가 양호하였다. 그리고, 광하제의 영향을 살펴보면 광화제를 사용하지 않았을 경우가 1.0MK KOH를 첨가하였을 때보다 결정성이 우수하게 나타났다. 이와같은 결과로부터 수열합성조건에서 Ba와 Ti의 출발물질이 [-OH]기를 가지고 있는 경우, 원료의 용해도를 증가시키고 출발물질의 수산기(hydroxide)의 생성이 용이하여 광화제의 첨가 없이도 BaTiO$_3$분말을 합성할 수 있음에 따라 공정단순화를 통해ㅐ 에너지 절감 효과를 가져올 수 있었다.

• 한국세라믹학회지
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• 제25권6호
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• pp.671-676
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• 1988

Preparation of high purity ultrafine Ba2Ti9O20 powder was investigated by coprecipitation method. Formation of Ba2Ti9O20 powder from precipitate of coprecipitation takes place at 120$0^{\circ}C$, which is 20$0^{\circ}C$ lower than that from mechanical mixtures of BaCO3 and TiO2. This is apparently due to the nature of the compounds formed by the reaction of mixtures of aqueous solutions of BaCl2 and TiCl4 with an ammoniacal solution of ammonium carbonate and ammouium hydroxide. In this method, the Ba2Ti9O20 powders show low callcining and sintering temperature and it has good sintering and dielectric constant at room temperature.

• 한국재료학회지
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• 제17권10호
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• pp.548-554
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• 2007

[ $BaTiO_3$ ] thick film by an interfacial polymerization method was prepared at the liquid/liquid interface between benzyl alcohol saturated solution with the basic catalyst [diethyl amine ($NHEt_2$) or triethylamine ($NEt_3$)], and the water dissolved with $TiO_2$ and $Ba(CH_3COO)_2$. The film thickness increased gradually with an increase in diethyl amine($NHEt_2$) or triethylamine($NEt_3$) volume and the reaction time. The homogeneity of $BaTiO_3$ thick film after sintered at $600^{\circ}C$ was confirmed by EPMA analysis, which showed that both of Ba and Ti element were homogeneously distributed on the surface as well as in the perpendicular direction of the film. The thickness of $BaTiO_3$ film obtained by this process was $8.75\;{\mu}m$.