• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.5
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• pp.434-439
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• 2008

Silver pastes as the outer electrodes have been prepared using Pb-free glass frits with different content of $Bi_2O_3$ and the effects of glass composition on the degradation behaviors of the Ag electrodes were investigated using the change of adhesion between Ag electrode and alumina substrate with thermal cycle stress. Low adhesion and high surface resistance were observed in Ag electrode using glass frit with a $Bi_2O_3$ content of 60 wt%, owing to the open microstructure formed at the firing temperature of $600^{\circ}C$. When the $Bi_2O_3$ was increased to 80 wt% in the glass frit, the Ag electrodes had a dense microstructure with high adhesion and a low surface resistance. Delamination of the Ag electrodes was a major failure mode under thermal cycle stress and this was attributed to residual stress due to the thermal expansion mismatch between the Ag electrode and the alumina substrate.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.6
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• pp.497-501
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• 2005

Dry film method was applied to fabricate lead-free transparent dielectric fur PDP(Plasma Display Panel). From various slurry compositions, it was able to find out the. best composition for producing high density green sheet. The slurry exhibited shear thinning characteristics which are known to be suitable fur producing a high quality green sheet. The thermal expansion coefficient of the fabricated transparent dielectric was measured to be $97{\times}10^{-7}/^{\circ}C$ which is close to the value of the glass substrate(PD-200). Cross sectional SEM of the transparent dielectric layer on PD-200 showed that the two layers were well attached each other with no observable gaps between them.

• Korean Journal of Materials Research
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• v.19 no.11
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• pp.613-618
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• 2009

We designed new compositions for lead free and low temperature sealing glass frit of $ZnO-V_2O_5-P_2O_5$ system, which can be used for PDP (Plasma Display Panel) or other electronic devices. The $ZnO-V_2O_5-P_2O_5$ system can be used as a sealing material at temperatures even lower than 430$^{\circ}C$. This system, however, showed lower bonding strength with glass substrate compared to commercialized Pb based sealing materials. So, we added $TiO_2$ as a promoter for bonding strength. We examined the effect of $TiO_2$ addition on sealing behaviors of $ZnO-V_2O_5-P_2O_5$ glasses with the data for flow button, wetting angle, temporary & permanent residual stress of glass substrate, EPMA analysis of interface between sealing materials and glass substrate, and bonding strength. As a result, sealing characteristics of $ZnO-V_2O_5-P_2O_5$ system glasses were improved with $TiO_2$ addition, but showed a maximum value at 5 mol% $TiO_2$ addition. The reason for improved bonding characteristics was considered to be the chemical interaction between glass substrate and sealing glass, and structural densification of sealing glass itself.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.935-937
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• 2006

Phosphate glass system is expected to be useful as a lead-free material in many devices in plasma display panels (PDP). The present study is mainly focused on the evaluation of interface reaction between ceramic fillers and phosphate glass matrix for barrier ribs in PDP. The results suggest that properties of barrier rib depend on the crystallization behavior and interface reaction between the fillers and glass matrix.

• Journal of the Korean Ceramic Society
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• v.48 no.1
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• pp.63-68
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• 2011

The investigation is directed to lead free (Pb-free) frits that can be used for organic light emitting diode, plasma display screen devices and other sealing materials. $P_2O_5$-SnO system glasses have been prepared for Pb-free low temperature glass frit. Structure and properties of the glasses with the composition SnO-$xB_2O_3-(60-x)P_2O_5$ (x=0, 5, 10, 15, 20, 25, 30, 35, 40 mol%) were characterized by infrared spectra (IR), X-ray diffraction(XRD), Density, Molar volume, Thermo mechanical analysis(TMA) and weight loss after immersion test. Glass transition temperature($T_g$), dilatometric softening temperature($T_d$) and chemical durability increased, and coefficient of thermal expansion($\alpha$) decrease with the substitution of $B_2O_3$ for $P_2O_5$ in the range of 0~25 mol%.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.335-335
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• 2010

$SiO_2$, $B_2O_3$, $Al_2O_3$, CaO, MgO, $Na_2O$, $ZrO_2$, $Bi_2O_3$를 이용하여 성질이 다른 두 종류의 무연계 프릿트를 제조하여 특성을 표준화 하였고, 이들 무연계 프릿트를 이용하여 Ag계 도체 및 $RuO_2$계 저항페이스트롤 제조하여 특성에 미치는 프릿트 조성의 영향을 연구하였다. $B_2O_3$를 첨가하여 퍼짐특성이 큰 프릿트의 경우 더 우수한 페이스트 특성을 나타내었다.

• Journal of the Korean Ceramic Society
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• v.47 no.5
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• pp.467-473
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• 2010

The objective of this study is to prepare lead-free thick film resistor (TFR) paste compatible with AlN substrate for hybrid microelectronics. For this purpose, CaO-ZnO-$B_2O_3-Al_2O_3-SiO_2$ glass system was chosen as a sintering aid of $RuO_2$. The effects of the weight ratio of CaO to ZnO in glass composition, the glass content and the sintering temperature on the electrical properties of TFR were investigated. $RuO_2$ as a conductive and glass powder were dispersed in an organic binder to obtain printable paste and then thick-film was formed by screen printing, followed by sintering at the range between $750^{\circ}C$ and $900^{\circ}C$ for 10 min with a heating rate of $50^{\circ}C$/min in an ambient atmosphere. The addition of ZnO to glass composition and sintering at higher temperature resulted in increasing sheet resistance and decreasing temperature coefficient of resistance. Using $RuO_2$-based resistor paste containing 40 wt%glass of CaO-20.5%ZnO-25%$B_2O_3$-7%$Al_2O_3$-15%$SiO_2$ composition, it is possible to produce thick film resistor on AlN substrate with sheet resistance of $10.6\Omega/\spuare$ and the temperature coefficient of resistance of 702ppm/$^{\circ}C$ after sintering at $850^{\circ}C$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.31-36
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• 2018

Fuses are used to protect electric circuits or devices from excess current. Glass-tube fuses are typically used, but problems have arisen due to the mandated switch from conventional solder to lead-free solder. This study used CFD to simulate the phenomenon of molten solder being poured out of a fuse during the soldering process for a fuse cap and fuse element. In addition, a method is proposed to prevent solder from overflowing, and its effectiveness was verified based on the analysis results. The results show that a sufficient increase of the temperature inside the glass tube before soldering and gravity can help to prevent the solder from overflowing.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.9
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• pp.646-650
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• 2013

$(Na,K)NbO_3$-based piezoelectric ceramics were synthesized by a liquid phase sintering method with a selected glass frit. The effects of the content of the glass frit and the sintering temperature on the microstructure and the electrical properties of the samples were investigated. With the 0.1 wt% of glass frit content, $(Na_{0.52}K_{0.44}Li_{0.06})(Nb_{0.84}Ta_{0.10}Sb_{0.06})O_3$ (NKL-NTS) ceramics showed the maximum values of the relative density (99.1%) and the electro-mechanical coupling factor ($k_p$: 0.32) at the sintering temperature of $1,050^{\circ}C$. It might mean that a liquid phase sintering with a suitable glass frit having the lower flow temperature could improve the relative density and the piezoelectric properties.

• Journal of the Microelectronics and Packaging Society
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• v.6 no.4
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• pp.55-59
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• 1999

One of lead free glass, Bi based solder glass is investigated for electronic packaging application. The melting temperature of glass about $550^{\circ}C$ at Bi based glass (70wt% $B_2O_3$ + l5wt%$B_2O_3$ + 8wt% $SiO_2$ + 2wt% $P_2O_5$ + 4wt% $A1_2O_3$ +lwt% ZnO) and varied with $P_2O_5$ content in this system. Crystallized glasses were obtainded after 1hr heat teratment at $450^{\circ}C$ with 10wt% of $P_2O_5$ addition. Much higher melting temperature was observed at $B_2O_3$ rich composition area.