• 한국세라믹학회지
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• 제24권6호
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• pp.537-542
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• 1987

The microstructure and electrical properties of Pb[(Sb1/2 Nb1/2)0.08 Zr0.49 Ti0.48]O3 with MnO2 addition have been investigated in this work. The amount of MnO2 addition was 0, 0.4, 0.8, 1.2, 2.0 wt%, respectively. The soild solution range of MnO2 that assumed in this composition according to thevariations of micro-structure and electrical properties was 0.4-0.8 wt%.

• 한국세라믹학회지
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• 제26권4호
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• pp.568-574
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• 1989

Effect of PbO addition on sintering and piezoelectric properties at 0.45Pb(Ni1/3Nb2/3)O3-0.40PbTiO3-0.15PbZrO3 composition which is tetragonal phase was investigated. In this composition, Porosity and dielectric constant were increased with excess PbO addition, but Kp and d31 was not changed. These variation of physical properties could be interpreted as composition change of solid grains from tetragonal to MPB region due to amount of PbO-rich liquid changing.

• 한국세라믹학회지
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• 제34권3호
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• pp.281-288
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• 1997

유전율이 높고 온도안정성이 우수하다고 알려져 있는 40Pb(Mg1/3Nb2/3)O3-30PbTiO3-30Pb(Mg1/2W1/2)O3계 세라믹스에 소결온도를 낮추기 위하여 저온에서 액상을 형성하는 91PbO-9WO3를 과잉첨가하여 소결성, 미세구조 및 유전성의 변화에 대하여 조사하였다. 91PbO-9WO3의 첨가량이 증가함에 따라 소결온도가 저하하였으며 6 mol%첨가시는 875$^{\circ}C$에서 소결이 가능하였다. 유전율은 기본조성에서 16,400이었고, 첨가제가 1 mol% 과잉첨가된 경우 18,500으로 최대값을 나타냈으며 이후 첨가량이 증가함에 따라 감소하였다. 첨가제의 첨가량이 2~4mol%인 시편의 온도에 따른 유전율 변화곡선에서 double peak maxima가 나타났으나, 첨가량이 5 mol% 이상인 시편에서는 입계에 텅스텐을 많이 포함하고 있는 결정상이 생성되었고 double peak maxima는 나타나지 않았다.

• Transactions on Electrical and Electronic Materials
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• 제8권5호
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• pp.201-205
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• 2007

Low temperature sintering behavior and microwave dielectric properties of the $BiNbO_{4^-}$ and the $ZnNb_2O_{6^-}zinc$ borosilicate glass(ZBS) systems were investigated with a view to applying the composition to LTCC technology. The addition of $10{\sim}30$ wt% ZBS in both systems ensured successful sintering below $900^{\circ}C$. For the $BiNbO_{4^-}ZBS$ system, the sintering was completed when 15 wt% ZBS was added whereas 25 wt% ZBS was necessary for the $ZnNb_2O_{6^-}zinc$ system. Secondary phase was not observed in the $BiNbO_{4^-}ZBS$ system but a small amount of $ZnNb_2O_6$ with the willemite structure as the secondary phase was observed in the $ZnNb_2O_{6^-}ZBS$ system. In terms of dielectric properties, the application of the $BiNbO_{4^-}$ and the $ZnNb_2O_{6^-}ZBS$ systems sintered at $900^{\circ}C$ to LTCC were shown to be appropriate; $BiNbO_{4^-}15$ wt% ZBS($\varepsilon_r=25,\;Q{\times}f\;value=3,700GHz,\;\tau_f=-32ppm/^{\circ}C$) and $ZnNb_2O_{6^-}25$ wt% ZBS($\varepsilon_r=15.8,\;Q{\times}f\;value=5,400GHz,\;\tau_f=-98ppm/^{\circ}C$).

• 한국결정성장학회지
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• 제15권3호
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• pp.120-123
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• 2005

[ $Li_2CO_3-V_2O_5$ ], flux를 사용한 liquid phase epitaxy(LPE) 법을 사용하여 $LiNbO_3$ (001) 기판위에 5 mol% ZnO가 첨가된 $LiNbO_3$, 박막과 2 mol% MgO가 첨가된 $LiNbO_3$, 박막을 성장시켰다. $Zn:LiNbO_3$, 막과 $Mg:LiNbO_3$, 막과의 결정성과 격자 부정합은 x-ray rocking curve(XRC)로 분석되었다. 그리고 다층 박막의 단면에서의 ZnO와 MgO의 분포가 electron probe micro analyzer(EPMA)를 사용하여 관측되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 제5회 학술대회 논문집 일렉트렛트 및 응용기술연구회
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• pp.90-95
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• 2003

The present paper is to investigate the phase stability and soft magnetic properties of amorphous CoNbZr films when Pd is added as a substitution for CoNbZr alloys. The films were prepared by a RF magnetron sputtering method. The CoNbZrPd films deposited on Si wafers exhibited amorphous structures being independent upon the amount of Pd added in the films. On the addition of 4.34% Pd, the excellent soft magnetic characteristics of the films were observed with a coercive force of 0.54 Oe and an anisotropy field of 11 Oe, whereas a coercive force of 1 Oe and an anisotropy field of 3.5 Oe were shown in the film without the addition of Pd. The increased anisotropy field and low coercive force of the films may be attributed to the occupancy of Pd in the preferred sites parallel to the external magnetic field applied on the deposition process. A permeability of about 1100 was kept constant in the operation frequency ranging up to 100 MHz, which can be explained by the Landau-Lifshitz formula.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.188-189
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• 2009

In this study, in order to develop excellent lead-free composition ceramics for piezoelectric transformer, $(K_4CuNb_8O_{23})$ added $(K_{0.5}Na_{0.5})(Nb_{0.96}Sb_{0.04})O_3$ ceramics were fabricated using conventional mixed oxide method and their piezoelectric and dielectric properties were investigated as a function of the amount of KCN addition. With increasing the amount of KCN addition, density and mechanical quality factor(Qm), electromechanical coupling factor (Kp) were increased up to 1.2mol% and then decreased. At the 1.2mol% KCN added specimen, mechanical quality factor (Qm), electromechanical coupling factor (Kp), density and dielectric constant (${\varepsilon}r$) showed the optimal values of 781, 0.445, $4.42g/cm^3$ and 443, respectively, for piezoelectric transformer application.

• 한국전기전자재료학회논문지
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• 제14권7호
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• pp.562-566
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• 2001

The effects of MnO$_2$ addition on the properties in Pb(Mg$_{1}$3/Nb$_{2}$3/)O$_3$ relaxor ferroelectrics were studied in the phase transition temperature range from -4$0^{\circ}C$ to 11$0^{\circ}C$. Specimens were made via solid state processing method. Dielectric properties, piezoelctric properties, electric-field-induced strain were examined to clarify the effect of MnO$_2$ addition in 0.9MN-0.1PT. As the amount of MnO$_2$ increases, the maximum dielectric constant and the dielectric loss decreases. Q$_{m}$ increased by increasing the doping contents of Mn. When 0.5wt% MnO$_2$ was doped, Q$_{m}$ increased from 95 to 480. The electric-filed-induced strain and polarization decreases as the amount of MnO$_2$ increases. From the experimental results, it was suggested that Mn behaves as an ferroelectric domain pinning element.ent.

• 한국전기전자재료학회논문지
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• 제16권8호
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• pp.676-680
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• 2003

In this study, to develop the low temperature sintering ceramics for piezoelectric transformer, PSN-PNN-PZT system ceramics were manufactured as a function of V$_2$O$_{5}$ addition, that is the low melting point oxide. Its dielectric and piezoelectric characteristics were investigated. With increasing the amount of V$_2$O$_{5}$ addition, electromechanical coupling factor(kp) and mechanical quality factor(Qm) were decreased. For piezoelectric transformer application, the 0.1wt% V$_2$O$_{5}$ added specimen sintered at 1,00$0^{\circ}C$ showed the proper value of $\varepsilon$r=1,590, kp=0.51 and Qm=748.m=748.

• 한국전기전자재료학회논문지
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• 제24권4호
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• pp.285-289
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• 2011

In this study, lead-free $(K_{0.5}Na_{0.5+X})(Nb_{0.96}Sb_{0.04})O_3+0.2mol%La_2O_3+1.2mol%$ $K_4CuNb_8O_{23}$ (X= 0~0.025) ceramics were fabricated by normal sintering method at $1060^{\circ}C$ for 5 h. Microstructures, piezoelectric and dielectric properties of specimens were investigated with special emphasis in the influence of Na excess addition. The grain size of specimen was slightly decreased with increasing Na content. In the 2 [mol%] Na excess addition of NKNS ceramics, density, electromechanical coupling factor, piezoelectric constant and electromechancal quality factor of specimen were found to reach the optimum values of 4.25 [$g/cm^3$], 0.4357, 154.43 [pC/N] and 580, respectively.