• Title/Summary/Keyword: $Bi_{2}O_{2}$

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A Study on the Thermal Properties and Plasma Resistance of Bi2O3-Al2O3-SiO2 Glass (Bi2O3-Al2O3-SiO2 유리의 열물성과 내플라즈마 특성 연구)

  • Young Min Byun;Jae Ho Choi;Won Bin Im;Hyeong Jun Kim
    • Journal of the Semiconductor & Display Technology
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    • v.22 no.1
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    • pp.64-71
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    • 2023
  • In this study, we investigated the effects of BiAlSiO glass composition on its glass forming range, thermal properties, and plasma resistance. The results showed that increasing the Al2O3 content suppressed the tendency for crystallization and hindered glass formation beyond a certain threshold. Bi2O3 was found to increase the content of non-bridging oxygen, resulting in a decrease in glass transition temperature and an increase in thermal expansion coefficient. Furthermore, the etching rate was found to improve with increasing Al2O3 content but decrease with increasing SiO2 content. It was concluded that the boiling point of fluorinated compounds should be considered to 900℃. Therefore, this study is expected to contribute to the understanding of the properties of BiAlSiO glass and its application to low temperature melting PRG compositions.

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Influence of Additives on Densification of Low-Temperature PZT Ceramics (저온소성용 PZT 세라믹스의 치밀화에 미치는 첨가제의 영향)

  • Park, Yong-Kap
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.5
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    • pp.995-999
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    • 2007
  • The lead zirconate titanate (PZT) powders were synthesized to make the piezoelectric ceramics in low temperature as low as $900^{\circ}C$. To investigate the influence of additives on sintering of PZT, two kinds of sintering aids were made as follows; $wB_2O_3-xBi_2O_3-zCuO$and LiBiO2-CuO. The sintering aid, $1{\sim}3$ wt.% $LiBiO_2-CuO$, was added into these PZT powders and the specimens were fired at temperature in the range of $800{\sim}1200^{\circ}C$. The highest density was shown in the specimen with 1 wt.% $LiBiO_2-CuO$ as additive at temperature of $900^{\circ}C$. The sintered specimen were analyzed by X-ray diffraction(XRD) and scanning electron microscopy (SEM) was utilized to observe the microstructure, especially the densified morphology of specimens. In the XRD pattern, the well-crystallized PZT phase could be obtained in consequence of firing at $900^{\circ}C$. The scanning electron microscopy(SEM) was utilized to observe the structure of specimens after firing at $900^{\circ}C$. The densified perovskite structure of $PbZrTiO_3$ could be obtained by sintering at temperature as low as $900^{\circ}C$. The high sinterability of PZT ceramics was attributed to the low formation temperature of the liquid phase of additives.

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Microwave Dielectric Properties of the $BaO-(Nd,Bi)_2 O_3-TiO_2$$_2$ Ceramic for Mobile Communication Component (이동 통신 부품에 이용되는 $BaO-(Nd,Bi)_2 O_3-TiO_2$계 마이크로파 유전체의 유전 특성)

  • 윤중락;이헌용;김경용;이석원
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.11
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    • pp.947-953
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    • 1998
  • The microwave dielectric properties of X BaO-0.15($Nd_{0.87}Bi_{0.13})_2O_3-(0.85-X)TiO_2 (X=0.14~0.17) and 0.16BaO-0.15(Bi_xNd_{1-x})_2O_3-0.69TiO_2$ (X=0.12~0.15) ceramics sintered at 1320~$1380^{\circ}C$ were investigated. The microwave dielectric properties of X BaO-0.15(Nd_{0.87}Bi_{0.13})_2O_3-(0.85-X)TiO_2$ (X=0.14~0.17) can be controlled effectively by adjusting X content : with increasing X from 0.14 to 0.17 both dielectric constant and temperature coefficient of resonant frequency decreased from 94.6 to 86 and from 22 ppm/^${\circ}C to -7 ppm/^{\circ}C$, respectively, while quality factor increased from 1300 to 1920 (at 4GHz). The microwave dielectric properties of 0.16BaO-0.15(Bi_x/Nd_{1-x2}O_3 -0.69TiO_2$ (X=0.12~0.15) can be controlled effectively by adjusting X content : with increasing X from 0.12 to 0.15 both quality factor and temperature coefficient of resonant frequency decreased from 1920 to 1430 and from 9 ppm/^${\circ}C to -10 ppm/^{\circ}C$, respectively, while dielectric constant increased from 87.5 to 92.6.

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Microstructure and Electrical Characteristics of ZnO-Bi2O3 Ceramics (ZnO-Bi2O3계 세라믹스의 미세구조 및 전기적 특성)

  • 이승주;한상목
    • Journal of the Korean Ceramic Society
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    • v.25 no.6
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    • pp.645-654
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    • 1988
  • The microstructure and electrical characteristics of ZnO-Bi2O3 ceramics containing 5mol% Bi2O3 have been studied in relation to sintering temperature and mode. The distribution and thickness of Bi2O3 intergranular layer was varied with sintering temperature and mode. Intergranular layer was more homogeneous with increasing sintering temperature, when sintering by direct heating and rapid cooling mode showed the best distribution of intergranular layer. These microstructural changes affected electrical characteristics directly, at 140$0^{\circ}C$ and C mode obtained high value of electrical resistivity and nonlinear exponent. Varistor voltage decreased with increasing sintering temperature, increased with decreasing holding time at high temperature. Barrier voltage obtained by calculation was about 1.5V.

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Preparation and Characterization of $Bi_{4-x}Sm_xTi_3O_{12}(0<\leqx\geq2)$ Thin Films Using Sol-Gel Processing (졸겔공정을 이용한 $Bi_{4-x}Sm_xTi_3O_{12}(0<\leqx\geq2)$ 박막제조 및 특성평가)

  • 이창민;고태경
    • Journal of the Korean Ceramic Society
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    • v.34 no.8
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    • pp.897-907
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    • 1997
  • Thin films of Bi4-xSmxTi3O12(0$\leq$x$\leq$2) were prepared on Pt/Ti/SiO2/Si(100) at $700^{\circ}C$ using spin-coating with sols derived from Bi-Sm-Ti complex alkoxides. From X-ray diffraction analysis, it was observed that Sm-substituted phases resembled ferroelectric Bi4Ti3O12 in structure. Variations of their lattice parameters depending on the amount of Sm-substitution showed that an anomalous structural distortion might exist at x=1. The grain sizes of the thin films decreased from 0.115 ${\mu}{\textrm}{m}$ to 0.078${\mu}{\textrm}{m}$ with increasing the amount of Sm-substitution. The dielectric constants and the remanent polarizations of the thin films decreased with increasing the amount of the Sm-substitution, which were related to decrease of the stereo-active Bi3+ ion contributing to polarization. However, these values were exceptionally high at x=1, compared to those of the other substituted phases. Such an anomaly suggests that the phase of x=1 has 1:1 chemical ordering between Sm and Bi in structure. The thin films of all compositions except x=2 showed ferroelectricity. The thin film of x=2 was paraelectric, whose grains were too fine to exhibit ferroelectricity.

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Dielectric properties of $BiNbO_4$ dielectric ceramics for multilayer microwave device (적층형 마이크로파 소자용 $BiNbO_4$ 유전체 세라믹스의 유전특성)

  • 박정흠;장낙원;윤광희;최형욱;박창엽
    • Electrical & Electronic Materials
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    • v.9 no.9
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    • pp.900-905
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    • 1996
  • We have investigated dielectric properties of low fired ceramics BiNbO$_{4}$ containing 0.05[wt%] V$_{2}$O$_{5}$ and x[wt%l Cr$_{2}$O$_{3}$ (x=0, 0.2, 0.4, 0.8, 1.2). By substituting Cr for Bi, dielectric constant .epsilon.$_{r}$ and quality factor Q.f increased and temperature coefficient of resonant frecquency .tau.$_{f}$ changed to positive value. In the composition of BiNbO$_{4}$+0.05 [Wt%] V$_{2}$O$_{5}$+0.8[wt%]Cr$_{2}$O$_{3}$ sintered at 960[.deg. C], we could obtain microwave dielectric properties of .epsilon.$_{r}$=49, Q.f.simeq.3000[GHz](at 4.8[GHz]), .tau.$_{f}$.simeq.0[ppm/.deg. C]. As the above ceramics can be sintered near 960[.deg. C], it is applicable to multilayer microwave device with Ag conductor.tor.tor.tor.

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