• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.693-696
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• 2001

The (Ba$_{0.3}$Bi$_{0.3}$Sr$_{0.4}$)TiO$_3$[BBST] ceramics were prepared by conventional mixed oxide method. The structural properties of the BBST ceramics with sintering temperature were investigated by XRD, SEM, EDS. In the case of BBST ceramics sintered at 1150~135$0^{\circ}C$, the $Ba_{0.5}$Sr$_{0.5}$TiO$_3$and SrBi$_4$Ti$_4$O$_{15}$ phase were coexisted. The 2$\theta$ value of the BST (110) peaks were shifted to the lower degree at the sintering temperature of 130$0^{\circ}C$ and 135$0^{\circ}C$. The grains of the BBST ceramics sintered at 130$0^{\circ}C$ and 135$0^{\circ}C$ were not appeared. Increasing the sintering temperature, the densities of the BBST ceramics were increased. In the BBST ceramics sintered at 130$0^{\circ}C$ and 135$0^{\circ}C$, the mole ratio of Bi was decreased.d.ed.d.d.d.

• 한국세라믹학회지
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• 제22권3호
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• pp.46-52
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• 1985

(Ba0.8. Sr0.2) $TiO_3$ semiconducting ceramic with and without Ti-excess composition were prepared by various sintering temperature. The effects of Ti compositions on the samples were discussed in terms of color micro-structure resistivity at room temperature and the positive temperature coefficient resistivity(PTCR). The 1.02mol Ti-excess composition provides better PTCR properties and has uniform micrositructures with 5-7${\mu}{\textrm}{m}$.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2004년도 춘계총회 및 연구발표회 초록집
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• pp.32.2-32.2
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• 2004

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 춘계총회,특별강연,심포지움,연구발표회
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• pp.29.2-29.2
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• 2000

• 한국재료학회:학술대회논문집
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• 한국재료학회 1997년도 한국재료학회 추계학술발표회
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• pp.130-130
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• 1997

• 한국전기전자재료학회논문지
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• 제15권11호
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• pp.933-938
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• 2002

(Ba,Sr)TiO$_{4}$ (BST) thin films on Pt/Ti/SiO$_{2}$/Si substrates were deposited by a sol-gel method and the etch characteristics of BST thin films have been investigated as a function of gas mixing ratio. The maximum etch rate of the BST films was 440 $AA$/min under such conditions as: CF$_{4}$(CF$_{4}$＋Ar) of 0.2, RF-power of 700 W, DC-bias voltage of -200 V, pressure of 15 mTorr and substrate temperature of 30 $^{circ}C$. The selectivities of BST to Pt, SiO$_{2}$ and PR were 0.38, 0.25 and 0.09, respectively. In the XPS (X-ray photoelectron spectroscopy) analysis, Barium (Ba) and Strontium (Sr) component in BST thin films formed low volatile compounds such as BaFx, SrFx, which are forms by the chemical reaction with F atoms and is removed by Ar ion bombardment. Titanium (Ti) is removed by chemical reaction such as TiF with ease. The result of secondary ion mass spectrometry (SIMS) analysis confirmed the existence of the BaFx, SrFK, TiFx.

• 한국진공학회지
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• 제4권S1호
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• pp.138-144
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• 1995

It is commonly believed that high permittivity materials will be necessary for future high density Gbit DRAMs. In a first part, we explain the choice of SrTiO3 by ECR MOCVD for Gbit-scale DRAMs. In a second part, after describing the ECR MOCVD system and presenting the requirements SrTiO3 thin films should meet for use in Gbit-scale DRAMs, the physical and electrical properties of srTiO3 thi film prepared by ECR MOCVD are then studied. A stacked capacitor technology, suitable for use in 1 Gbit DRAM, and comprising high permittivity SrTiO3 thin films prepared by ECR MOCVD at $450^{\circ}C$ on electron beam and RIE patterned RuO2/TiN storage nodes is finally described.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1992년도 제3회 학술발표회 논문개요집
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• pp.35-35
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• 1992

• 한국세라믹학회지
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• 제22권2호
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• pp.63-67
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• 1985

$BaTiO_3$ and $SrTiO_2$ were mixed with the mole ratio of 36:65:50, 50: 50 and 65:35 and then heated at 110$0^{\circ}C$~130$0^{\circ}C$ for 1~64 hrs. The solid state reactions and dielectric properties were investigated as a function of amount of solid solution. Activation energy of solid solution decreased with increasing amount of $BaTiO_3$ due to fast diffusion of $Ba^{2+}$ ions. Dielectric constants increased with increasing the soaking time at 125$0^{\circ}C$and 130$0^{\circ}C$ and Curie Temperature shifted to higher temperature with increasing the soaking time at 125$0^{\circ}C$ and 130$0^{\circ}C$. It attributes to the am-ount of solid solution and grain growth, Dielectric constants decreased and Curie Temperature shifted to lower temperature due to decreasing polari-zability.

• 한국전기전자재료학회논문지
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• 제11권9호
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• pp.711-717
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• 1998

BST(70/30) and BST(50/50) thin films were prepared by Sol-Gel method and studied about the microstructural and dielectric properties with Pt and ITO bottom electrodes. The stock solution was synthesized and spin coated on the Pt/Ti$SiO_2$/Si and Indium Tin Oxide(ITO)/ glass substrate. the coated films were dries at 350$^{\circ}C$ for 10 minutes and annealed at $750^{\circ}C$ for 1 hour for the crystallization. The thin films coated on ITO substrate were crystallized easily and the packing density and roughness of surface were better that those of films coated on Pt substrates. In the BST(50/50) composition the structural properties were similar to the BST(70/30) composition and grain size were decreased with increasing the contents of Sr. The dielectric constant was higher in the BST(50/50) composition compared with the BST(70/30) composition. Using the ITO substrate, the dielectric constant was higher than the Pt substrate while the dielectric loss was showed a reverse trend. The dielectric constant with and increase of temperature was decreased slowly.