• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.5
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• pp.440-446
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• 2008

To manufacture the MLCC with X7R for high voltage stability, $BaTiO_3-MgO-MnO_2-Y_2O_3$ with $(Ba_{0.4}Ca_{0.6})SiO_3$ glass frit was formulated. Based on this composition, the addition of $Er_2O_3$ showed that TCC(Temperature Coefficient Capacitance) at $85^{\circ}C$ was improved from 5 % to ${\sim}0\;%$, but the dielectric constant and IR (Insulation Resistance) were decreased. The glass frit improved the dielectric constant and IR, so the appropriate contents of $Er_2O_3$ and glass frit were 0.6 mol% and 1 wt%, respectively. It showed that the dielectric constant and RC constant were 2,550 and 2,000 (${\Omega}F$), respectively in the sintering condition at $1250^{\circ}C$ in PO2 $10^{-7}$ Mpa. The MLCC with $3.2{\times}1.6$ (mm) size and $1\;{\mu}F$ was also suited for X7R with the above composition.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.30 no.3
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• pp.30-38
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• 2016

In this research, a 6W white LED package with a Glass Remote Phosphor was developed to improve the life of an LED package. The Glass Remote Phosphor was fabricated by the Phosphor in Glass (PiG) method, wherein phosphor YAG:Ce was mixed with glass frit and then heat treated. A paste with 75wt.% of a phosphor substance and 25wt.% glass frit was coated on a glass substrate two times using the screen-printing technique and heat-treated at $800^{\circ}C$ ; this structure gave a luminous efficacy of 136.1lm/W, color rendering index of 74Ra, and color temperature of 5,342K, thus satisfying the requirements as a light source for lighting. Moreover, an IES LM-80 accelerated life test was conducted on the same LED package for 6,000h in order to estimate the L70 lifetime based on IES TM-21. The results showed guaranteed lifetimes of 213,000h at $55^{\circ}C$, 245,000h at $85^{\circ}C$, and 209,000h at $95^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.47 no.2
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• pp.146-150
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• 2010

Because the plasma display panel has used red, green and blue(RGB) phosphors, it has suffer from two intrinsic problems; 1) the cell defect due to the lack of binding force between phosphor particles and 2) mis-discharge because of difference of electrical characteristics among RGB phosphors. In order to control the mechanical and electrical properties of RGB phosphors, frit with $ZnOB_2O_3-SiO_2-Al_2O_3$ system was added to RGB phosphor as sintering additive. The mechanical properties were increased by the amount of frit. The amount of frit under 5 wt% rarely affected dielectric constant. However, there was the limit of amount because of decreasing optical properties seriously; over 3 wt% in red, over 10 wt% in green and blue.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.655-657
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• 2002

The carbon nanotube emitters for field emission displays were fabricated by screen printing techniques. The pastes for screen printing are composed of organic binders, carbon nanotubes, and some additive materials. Then the pastes were printed on Cr-coated/Ag-printed soda-lime glass substrates. From the I-V characteristics, the turn-on field of SWNT was lower than that of MWNT. The decrease in the mesh size of screen masks resulted in decreasing the turn-on field and increasing the electron emission current. When the carbon nanotubes were mixed with glass frit, glass frit appeared to contribute to the vertically aligning of carbon nanotubes on glass.

• Journal of Technologic Dentistry
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• v.14 no.1
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• pp.95-118
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• 1992

Glass ceramics for crown were prepared by adding 3$\sim$11 wt% TiO2 to the weight percent composition of 34.7 CaO, 27.8 SiO2, 18.3P2O5, 12.6MgO and 6.6 TiO2. The starting glasses were prepared by melting the powdered batch in alumina crucible at 1350$\sim$1400 for 1 hr and then quenching into a distilled water. The nucleation and crystallization of the crystalline glass ceramics for crown were studied by DTA, SME and X-ray diffraction analysis. Frit containing 9.11 wt% TiO2 had crystallization temperature of 850$\sim$1075 and major crystalline phase was identified by X-ray diffraction as diopside(CaO-MgO-2SiO2). Activation energies for the crystallization processes were obtained from DTA by varing rates for the fits, and were calculated from modified Ozawa and Kissinger equations. Activation energy for the crystallization processes of the S-4 frit was 489.6 KJ/mol.

• Journal of the Korean Ceramic Society
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• v.54 no.5
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• pp.400-405
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• 2017

$P_2O_5-ZnO-SiO_2-R_2O$ glasses were synthesized as a sealing material for large scale dye-sensitized solar cells (DSSC). Compositional effects of $P_2O_5$ and ZnO were examined by varying their contents. Their viscosity and glass stability at sintering temperatures of less than $550^{\circ}C$ were examined by flow button test. Glass transition temperature and structural change upon compositional change were investigated. Chemical stability against electrolyte was also examined by immersing the glasses in the electrolyte for 72 h at $85^{\circ}C$.

• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.18-26
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• 1957

There are two problems to be solved by our efforts in the enamel frit. One is how we can cover the enamel frit thin with complete milk white as possible, and the other is how it can be, made resistant for chemicals than before one. The frit which can solved the two problems just mentioned above is titanium enamel frit. This frit has been developed in America after War Ⅱ, and now the research for concerning antimony frit into titanium frit is under development entirely. In order to develope the enamel industry in Korea, it is urgent problem to convert antimony frit into titanium frit. By the way the titanium frit is emulsified titanium oxide crystal which made through reheating the supersaturated solution of titanium oxide in the basis of glass. Unfortunately, there are many obscure points in active fact or which influence on its composition and characteristics yet. However, this task was tried for the first in Korea. As first step, the test was carried on the reference books, and we can be possible convert antimony frit into titanium frit as a result of this experiment. As a conclusion, for the purpose of developing the enamel industry in Korea, we studied that the research for converting antimony enamel frit which has been used popularly into titanium enamel frit which is more economic and resistant for chemicals. As a result of experiments, the following points concerning with titanium frit have become clearly. 1. It is better when the composition of titanium enamel frit has as following table.Man Duck San Silica 24 An Yang Feldspar 20 Borax 28 Sodium Nitrate 4 Cryolite 7 Calcium Carbonate 3.6∼1 Titanium Oxide 10 Calcium phosphate 0 ∼3.2 Calcium Fluoride 0∼1.8 Antimony Oxide 0∼0.5 2. The amount of $TiO_2$, to be added is $10%\;to\;12{%,\;CaF_2\;is\;under\;1.8%,\;P_2O_5\;is\;under\;1.6%,\;Sb_2O_3\;is\;under\;0.5%$. 3. In the titanium frit, the limit of iron oxide amount to be included is under 0. 5%. 4. Comparing the titanium enamel frit with antimony enamel frit not only the titanium frit can be savely 20.6% in the price of raw materials, but one time of glazing and heating process is omitted in each case, and it is known the titanium frit is more resistant for chemicals than antimony frit.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.8
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• pp.489-493
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• 2016

In this study, the effect of vanadium oxide ($V_2O_5$) content and pre-sintering atmosphere on sealing property of glass frit that consisted of $V_2O_5-BaO-ZnO-P_2O_5-TeO_2-CuO-Fe_2O_3-SeO_2$ was investigated by XPS (X-ray photoelectron spectroscopy). The content of V2O5 was changed to 15, 30, and 45 mol%, and the pre-sintering was carried out in air and $N_2$ condition, respectively. XPS analysis conducted before and after laser irradiation with identical sample. Before laser treatment, glass frits that were pre-sintered at air condition showed both $V^{4+}$ and $V^{5+}$, but the valence state was changed to $V^{5+}$ after laser irradiation when the glass frits contained 30 and 45 mol% $V_2O_5$; this change led to non-adhesive property. On the other hand, glass frits that were pre-sintered at $N_2$ condition exhibited only $V^{4+}$ and it showed fine adhesion irrespective of the $V_2O_5$ content. As a result, the existence of $V^{4+}$ seems to be a major factor for controlling the adhesive property of glass frit for laser sealing.

• Korean Journal of Materials Research
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• v.14 no.10
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• pp.731-736
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• 2004

Herein, we report on the co-firing of a low-K wiring substrate and a middle-K functional substrate in LTCC. Firstly, we researched the sintering behavior and dielectric properties of the low-k wiring substrate comprised by alumina and glass frit with ${\varepsilon}_r$, of $\sim7$ and the middle-k functional substrate comprised by $Ba_{5}Nb_{4}O_{15}$ and glass frit with ${\varepsilon}_r$, of $20\sim30$. The warpage and delamination between the hetero layers of the low-K and the middle-K composition were also studied. In particular, physical matching of the hetero layers could be possible by adjusting of the sintering properties of the composition. We observed that an introduction of the glass frit to the low- and middle-K substrate gives rise to a minimization of an effect given by separation of the hetero layers, and modification of the fraction of the glass frit accompanied by a variation of the composition could control the sintering behavior and its beginning temperature. In the case of co-firing of the L03 as the low-K wiring substrate composition and the M03 as the middle-K functional substrate composition at $875^{\circ}C$, we could fabricate a desirable structure of hetero layers without any kinds of structural defects such as separation, warpage, delamination, pore trap, etc. We suppose that the co-firing techniques described in this study would provide a helpful method to fabricate a LTCC multi-functional for the next generation.

• Journal of the Korean Ceramic Society
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• v.52 no.2
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• pp.114-118
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• 2015

$V_2O_5-P_2O_5-ZnO-Sb_2O_3$ glasses modified with BaO and $Al_2O_3$ are synthesized as a sealing material for large-scale dye-sensitized solar cells (DSSCs). A compositional study is performed in order to determine the glass that can be sintered below $500^{\circ}C$ with a high chemical stability against the electrolyte. The flow size of the glasses after the heat treatment and the glass stability are increased with the addition of $Al_2O_3$ and BaO, while the glass transition temperature is decreased. After the reaction with the electrolyte at $60^{\circ}C$ for 72 h, the addition of 5 mol% of BaO and 2 mol% of $Al_2O_3$ considerably enhances the chemical stability of the glass. X-ray diffraction (XRD) and scanning electron microscope (SEM) are used to examine the reaction between the electrolyte and glasses. The structural contribution of the additives is also investigated and discussed.