• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.11a
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• pp.88-95
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• 2001

Silicon nitride based ceramics reinforced with 3wt% Si$_{3}$N$_{4}$ whisker was prepared by tape casting to investigate the effect of microstructure on erosion behaviors. Hardness and fracture toughness were measured with prepared specimens. A gas blast type erosion tester was used to examine the erosion behavior of the specimens with different impact directions and angles. The erosion rate increases with increasing impact angle. Erosion rate of the silicon nitride ceramics also depends on the grain orientations, The erosion rate was lowered when impaction direction was parallel to the grain orientation This result was explained by the crack deflection and bridging due to the grain orientation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.7
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• pp.583-591
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• 2000

It this paper the multilayer chip band pass filter for next generation mobile communication phone is fabricated and designed. For the design the multilayer chip filter of non-contented equivalent circuit and contented equivalent circuit with attenuation pole is presented. Finally it is fabricated and designed using the multilayer chip filter of contented equivalent circuit with attenuation pole. The size insertion loss center frequency and band width of multilayer chip filter are 4.5$\times$3.2$\times$2.0[mm], 3.0[d.B] and 1945$\pm$25 MHz respectively. The multilayer chip filter was fabricated by screen printing with Ag electrode after tape casting. Simulation results of multilayer chip filter are compared with experimental results and found to be in excellent agreements.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.390-393
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• 2001

This study demonstrated the feasibility of tape casting method to fabricate soda borosilicate glass-coated stainless steel electrostatic chucks(ESC) for low temperature semiconductor processes. The glass coatings on the stainless steel substrates ranged from 100 $\mu\textrm{m}$ to 150 $\mu\textrm{m}$ thick. The adhesion of the glass coatings was found to be excellent such that it was able to withstand moderate impact tests and temperature cycling to over 300$^{\circ}C$ without cracking and delamination. The electrostatic clamping pressure generally followed the theoretical voltage-squared curve except at elevated temperatures and higher applied voltages when deviations were observed to occur. The deviation is due to increased leakage current at higher temperature and applied voltage as the electrical resistivity drops.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.43-43
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• 2007

LTCC는 최근의 이동 통신 환경의 급격한 발전 속에 그 응용 및 특성 요구가 증폭되고 있다. 이러한 LTCC 소재는 주로 테이프 캐스팅에 의한 후막 공정으로 제품이 만들어지게 되는데, 캐스팅을 위해 제조되는 슬러리는 일반적으로 유변학적 의사가소성 거동을 하는 것으로 알려져 있다. 그러나, 슬러리 제조 조건에 따라 유변학적 거동이 다르게 나타나는 것이 관찰되었다. 이에, 슬러리 제조 조건을 다양하게 변화시키며, 유변학적 거동을 살며 보고 이렇게 변화된 유변학적 거동과 캐스팅된 시트 특성과의 관계를 검토해 보려 한다. LTCC 재료의 주 구성 요소인 glass와 세라믹 분말의 초기 조건 및 각각의 rheology 특성과 혼합 슬러리에서의 관계성 등을 고찰하려 한다.

• 한국전기화학회:학술대회논문집
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• 2002.07a
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• pp.281-286
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• 2002

• Proceedings of the Materials Research Society of Korea Conference
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• 2000.11a
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• pp.151-151
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• 2000

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.114.3-114
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• 1998

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.382-385
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• 2001

In the previous study, a new LTCC material in the PbWO$_4$-TiO$_2$-B$_2$O$_3$-CuO system was introduced. The developed material can be sintered at 850$^{\circ}C$ and its dielectric properties are $\varepsilon$$\sub$r/=20-25, Qxf$\sub$o/=30000∼500000Hz, and $\tau$$\sub$f/=0.2∼30ppm/$^{\circ}C$, respectively Therefore this material can be used as a LTCC substrate material for fabrication of multilayered high frequency communication module set. In present study, using this material, tape casting condition was established. With this condition, a multilayered resonator was fabricated and its electrical properties were examined. In present study, an antenna-duplexer module was also fabricated. Frequency characteristics of as-fabricated antenna-duplexer module was compared with simulation results.

• Journal of Powder Materials
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• v.23 no.5
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• pp.379-383
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• 2016

A thick film of $Li_7La_3Zr_2O_{12}$ (LLZO) solid-state electrolyte is fabricated using the tape casting process and is compared to a bulk specimen in terms of the density, microstructure, and ion conductivity. The final thickness of LLZO film after sintering is $240{\mu}m$ which is stacked up with four sheets of LLZO green films including polymeric binders. The relative density of the LLZO film is 83%, which is almost the same as that of the bulk specimen. The ion conductivity of a LLZO thick film is $2.81{\times}10^{-4}S/cm$, which is also similar to that of the bulk specimen, $2.54{\times}10^{-4}S/cm$. However, the microstructure shows a large difference in the grain size between the thick film and the bulk specimen. Although the grain boundary area is different between the thick film and the bulk specimen, the fact that both the ion conductivities are very similar means that no secondary phase exists at the grain boundary, which is thought to originate from nonstoichiometry or contamination.

• Journal of the Korean Ceramic Society
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• v.41 no.4
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• pp.277-283
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• 2004

To fabricate green sheet of transparent dielectric for PDP front panel, dispersion of transparent dielectric slurry, density, and mechanical properties of green sheets have been investigated as a function of amount and composition of organic additives. Measurements of sedimentation and viscosity were employed to determine a proper dispersant and its amount for a well dispersed transparent dielectric powders in non-aqueous system. Green sheets, having various ratios of transparent dielectric powders to transparent dielectric powders＋ binder＋plasticizer and binder to binder＋plasticizer, were fabricated. All the tape casting slurries showed shear thinning effect, that is, the apparent viscosity decreased with the increase of shear rate. It was found that the amount and composition of organic additives were main variables to affect densities and mechanical properties of transparent dielectric green sheets for PDP.