• Title/Summary/Keyword: Alkaline-earth glass

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Corrosion of Refractory in Glass Melts for Plasma Display Panel Substrate (Plasma Display Panel용 기판 유리용융체의 내화물 침식)

  • Kim, Ki-Dong;Jung, Hyun-Su;Kim, Hyo-Kwang
    • Journal of the Korean Ceramic Society
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    • v.44 no.1 s.296
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    • pp.65-69
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    • 2007
  • For self-developed alkali-alkaline earth-silicate and commercial glass melts for plasma display panel substrate, the corrosion behavior of fused casting refractory consisting of $Al_2O_3-ZrO_2-SiO_2$ was examined at the temperature corresponding to $10^2\;dPa{\cdot}s$ of melt viscosity by static finger methode. The corroded refractory specimens showed a typical concave shape due to interfacial convection of melts at their flux line. However, the corrosion thickness by commercial glass melts was $6\sim10$ times comparing to that by the self?developed melts. From the view point of the glass composition and the role of alkaline earth in glass network, it was discussed the effect of alkali/alkaline earth diffusion and temperature on the refractory corrosion.

Redox Behavior of Sn and S in Alkaline Earth Borosilicate Glass Melts with 1 mol% Na2O

  • Kim, Ki-Dong;Kim, Hyo-Kwang
    • Journal of the Korean Ceramic Society
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    • v.46 no.3
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    • pp.271-274
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    • 2009
  • Redox investigation of Sn and S ion was attempted in alkaline earth borosilicate glass melts with only 1 mol% $Na_2O$ by means of Square Wave Voltammetry (SWV). According to voltammograms, there was only one peak due to $Sn^{4+}/Sn^{2+}$ in melt doped with $SnO_2$. The calculated standard enthalpy and entropy of the reduction of $Sn^{4+}$ to $Sn^{2+}$ were 116kJ/mole and 62 J/mol K, respectively. The determined redox ratio, [$Sn^{2+}$] / [$Sn^{4+}$] in the temperature range of $1300{\sim}1600^{\circ}C$ was in $0.4{\sim}2.1$. On the contrary, in the voltammogram of melt doped with $BaSO_4$ there was no peak due to $S^{4+}/S^o$ but shoulder that might be attributed to the adsorption of sulfur at the electrode. The absence of the peak related with $S^{4+}/S^o$ was discussed from the view-point of the thermal decomposition behavior of $BaSO_4$ in the glass batch.

Effect of Alkaline Earth Metal Oxides addition on the Low-voltage Characteristics of MgO Films as a Protective layer for AC PDPs (PDP 보호막용 MgO 박막의 저전압 특성에 미치는 알카리토금속산화물 첨가 효과)

  • Jo, Jin-Hui;Kim, Rak-Hwan;Kim, Jeong-Yeol;Lee, Yu-Gi;Kim, Hui-Jae;Park, Jong-Wan
    • Korean Journal of Materials Research
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    • v.9 no.5
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    • pp.441-445
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    • 1999
  • Alkaline earth metal oxides were added to the conventional MgO films as a protective layer for dielectric materials to have lower firing voltage(Vf) of the plasma display panel(PDP). Panels with various protective layers of MgO-alkaline earth metal oxides were prepared on glass by using e-beam evaporation and its effect on firing voltage characteristics were investigated. (Ba-Mg)O films had poor voltage characteristics because of higher activation energy of BaO. But, (Sr-Mg)O, (Ca-Mg)O and (Ca-Sr-Mg) O had better voltage characteristics than the conventional MgO. A mixture film of (Mg-Ca-Sr)O show the lowest firing voltage which is less than that of MgO by 20V. The chemical composition to have lowest firing voltage is MgO:SrO:CaO ratio of 6:2:2. The mixture of MgO-Alkaline earth metal oxides films showed good transmittance properties within the visual range.

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Study on Filler Effects of High Temperature Glass Sealant (고온용 유리 봉합재의 filler 첨가효과)

  • 손용배;김상우;김민호
    • Journal of the Microelectronics and Packaging Society
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    • v.6 no.1
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    • pp.51-58
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    • 1999
  • The effects of glass composition on the wettability and reactivity with $ZrO_2$substrate was evaluated and fabrication variables and glass compositions was investigated. Various glass compositions was investigated. Alkaline earth silicate glass show good wettability and lower viscosity and crystallization of glass could be prevented by $B_2O_3$.The sealant glass begin to wet on $ZrO_2$substrate below $900^{\circ}C$ and porosity occurred in various glass compositions, the crystallization and porosity in the glass could be prevented by the addition of flux into glass composition. But flowability and reactivity of glass with $ZrO_2$substrate was enhanced. Processing variables should be optimized to reduce the porosity by enhancing the sintering of glass powder. Many silicate glasses were investigated for the applications of high temperature sealants. Wetting and bonding of glass was good enough to seal together between $ZrO_2$and other ceramic components of SOFC. But porosity and reaction layer were occurred in the sealant glass. It will be possible to produce glass sealant without porosity and reaction layer at the interface by optimization of processing variable and modify the glass compositions. In present study, wettability of glass-filler composite was investigated. The porosity, shape of filler and interfacial reactions of sealant glass with fillers were examined.

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Effects of Fluorine Addition on Thermal Properties and Plasma Resistance of MgO-Al2O3-SiO2 Glass (MgO-Al2O3-SiO2계 유리 열물성 및 내플라즈마 특성에 대한 Fluorine 첨가의 영향)

  • Yoon, Ji Sob;Choi, Jae Ho;Jung, YoonSung;Min, Kyung Won;Kim, Hyeong-Jun
    • Journal of the Semiconductor & Display Technology
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    • v.21 no.1
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    • pp.119-126
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    • 2022
  • MAS-based glass, which has been studied to replace the ceramic material used in the plasma etching chamber, has problems such as forming and processing due to its high melting temperature. To solve this problem, in this study, fluoride was added to the existing MAS-based glass to increase the workability in the glass manufacturing and to improve the chemical resistance to CF4/Ar/O2 plasma gas. Through RAMAN analysis, the structural change of the glass according to the addition of fluoride was observed. In addition, it was confirmed that high-temperature viscosity and thermal properties decreased as the fluoride content increased and plasma resistance was maintained, it showed an excellent etching rate of up to 11 times compared to quartz glass.

Melt Properties of Plasma Display Panel Substrate Glasses Based on Float Process (Float 공법을 고려한 Plasma Display Panel용 기판유리 용융체의 특성)

  • Kim, Ki-Dong;Jung, Woo-Man;Jung, Hyun-Su;Kwon, Sung-Ku;Choi, Se-Young
    • Journal of the Korean Ceramic Society
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    • v.43 no.7 s.290
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    • pp.433-438
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    • 2006
  • In order to examine the working condition of melts in tin bath of float process it was investigated Sn diffusion behavior and solidification rate of melts for alkali-alkaline earth-silica PDP substrate glasses such as commercial CaO rich CS-77 glass, commercial $Al_2O_3$ rich PD-200 glass and self developed $SiO_2$ rich T-series (T-2, T-4, T-6) glasses. In the case of Sn depth and concentration created in glass surface by ion exchange between Sn and alkali, T-series showed lower value than CS-77, especially T-2 is more excellent than PD-200. The solidification rate of melts expressed by cooling time between $log{\eta}=4\;and\;7.6dPa{\cdot}s$ was low for T-series comparing with CS-77 and PD-200. Therefore, it was concluded that T-series is desirable considering forming condition in the tin bath of the float process.

Electrochemical Approach in Plasma Display Panel Glass Melts doped with Sulfate and Sulfide II. Square Wave Voltammetry

  • Kim, Ki-Dong
    • Journal of the Korean Ceramic Society
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    • v.45 no.7
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    • pp.375-379
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    • 2008
  • Redox behavior was observed in alkali alkaline earth silicate PDP (Plasma Display Panel) glass melts doped with sulfate and sulfide by square wave voltammetry (SWV). According to voltammograms produced at a temperature range of 1100 to $1400^{\circ}C$ and frequency range of 5 to 1000 Hz, both melts showed the same behavior in which there is one reduction peak at low frequency but another peak at an increase of frequency. Based on the frequency dependence of the peak current, self diffusivity of $S^{4+}$ was determined. Based on the temperature dependence of the peak potential, standard enthalpy (${\Delta}H^0$) and standard entropy (${\Delta}S^0$) for the reduction of $S^{4+}$ to $S^0$ were calculated.

Glass Inclusions in Quartz Phenocrysts of Tuff from Sunshin Au Mining Area, Haenam, Jeonnam. (전남 해남의 순신 금광산 지역에 산출하는 응회질암에 포획된 유리포유물)

  • Lee, Seung-Yeol;Yang, Kyoung-Hee;Jeon, Byung-Geun;Bak, Gil;Koh, Sang-Mo;Seo, Jeong-Ryul
    • The Journal of the Petrological Society of Korea
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    • v.18 no.4
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    • pp.337-348
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    • 2009
  • Clear and homogeneous glass inclusions are well preserved at the rim of the quartz phenocrysts of tuff from Sunshin epithermal Au deposit, Haenam, although the host rocks experienced extensive silicification and argillic alteration. Glass inclusion vary in size from $5\;{\mu}m$ to larger than $200\;{\mu}m$ consisting of glass(60~80 vol%) + vapor bubble(15~30 vol%) $\pm$ daughter crystals(<10 vol%). Most of glass inclusions are cubic to rectangular in shape, indicating that the host quartz grew in the stability field of $\beta$-quartz. All the glass inclusions appear to be primary. Glass inclusions are composed of highly evolved high-K calc-alkaline rhyolites, which can represent the final liquidus phase of the magma system. The $Au_2O_3$ concentration (<0.30 wt%) is trivial in the glass, indicating there was no enrichment in the final residual melt. Textural characteristics suggest that magma was water-saturated shortly before or during the eruption. $H_2O$ content of the glass (ca. 2-4 wt%) suggests a water saturation pressure($P_{H2O}$) of about 300-900 bars. This pressure implies a minimum depth of 0.8-2.5 km for the magma chamber.

Study on Thermal Properties and Plasma Resistance of MgO-Al2O3-SiO2 Glass (MgO-Al2O3-SiO2계 유리의 열물성과 내플라즈마성 연구)

  • Yoon, Ji Sob;Choi, Jae Ho;Jung, YoonSung;Min, Kyung Won;Im, Won Bin;Kim, Hyeong-Jun
    • Journal of the Semiconductor & Display Technology
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    • v.20 no.2
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    • pp.61-66
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    • 2021
  • In this study, we studied the alternative of plasma resistant ceramic parts that constitute plasma chambers in the semiconductor dry etching process. MgO-Al2O3-SiO2(MAS) glass was made of 13 types of glass using the Design Of Experiments(DOE) and the effect on thermal properties such as glass transition temperature and crystallization temperature depending on the content of each composition and etching resistance to CF4/O2/Ar plasma gas. MAS glass showed excellent plasma resistance and surface roughness up to 20 times higher than quartz glass. As the content of Al2O3 and MgO increases, the plasma resistance is improved, and it has been confirmed that it has an inverse relationship with SiO2.