• 한국세라믹학회지
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• 제39권11호
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• pp.1017-1022
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• 2002

$(Ba_{1-x}Ca_x)(Ti_{1-y}Zr_y)O_3(BCTZ)$ powders for the Ni-electrode Multilayer Ceramic Capacitor(MLCC) were synthesized via hydrothermal treatment using mixed aqueous solutions of $BaCl_2{\cdot}2H_2O,\Ca(NO_3)2{\cdot}4H_2O,\ ZrOCl_2{\cdot}8H_2O$ and $TiCl_4$. Two component and three component systems were also extensively studied for basic data. BT, CT and BZ powders were crystalline but CZ was determined to be amorphous under the same synthetic condition. In BTZ system, Zr and Ti were completely soluble and Ca would be substituted for Ba up to ∼6 mol% in BCT. The submicron-sized $(Ba_{0.95}Ca_{0.05})(Ti_{0.80}Zr_{0.20})O_3$ powder of the target composition was successfully synthesized at $150{\circ}$ for 12h.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 춘계총회,특별강연,심포지움,연구발표회
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• pp.17.2-17.2
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• 2000

• Bulletin of the Korean Chemical Society
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• 제19권8호
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• pp.830-835
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• 1998

The characteristics of the ablation plume generated by 532 nm Nd: YAG laser irradiation of a Pb(Zr0.52Ti0.48)O3 (PZT) target have been investigated using a pulsed-field time-of-flight mass spectrometer (TOFMS). The relative abundance of O+, Ti+, Zr+, Pb+, TiO+, and ZrO+ ions has been measured and discussed. TiO+ and ZrO+ ions were also found to be particularly stable within the laser ablation plasma with respect to PbO+ species. The behavior of the temporal distributions of each ionic species was studied as a function of the delay time between the laser shot and the ion extraction pulse. The most probable velocity of each ablated ion is estimated to be Vmp=1.1-1.6x 105 cm/s at a laser fluence of 1.2 J/cm2, which is typically employed for the thin film deposition of PZT. The TOF distribution of Ti+ and Zr+ ions shows a trimodal distribution with one fast and two slow velocity components. The fast velocity component (6.8x 10' cm/s) appears to consist of directly ablated species via nonthermal process. The second component, originated from the thermal evaporation process, has a characteristic velocity of 1.4-1.6 x 105 cm/s. The slowest component (1.2 x 105 cm/s) is composed of a dissociation product formed from the corresponding oxide ion.

• 한국세라믹학회지
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• 제36권9호
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• pp.915-922
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• 1999

Microwave dielectric properties and far infrared reflectivity spectra of the (Zr0.8Sn0.2)TiO4 ceramics were inves-tigated with the various cooling rate. Dielectric constant was nearly same value while the unloaded Q value was largely affected by cooling rate. The Q.f of 42,140 at 7 GHz was obtained for the specimens with cooling rate of 1$^{\circ}C$/min. The effect of the cooling rate on the change of the ionic the electronic polarization and the intrinsic microwave loss of the specimens were investigated by the infrared reflectivity spectra from 50 to 4000cm-1 which were calculated by Kramers-Kroning analysis and the classical oscillator model. The relative tendency of microwave dielectric properties of the specimens calculated from the relfectivity data were in good agreement with the results by the post resonant method.

• 한국재료학회지
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• 제9권10호
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• pp.1041-1046
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• 1999

(Zr(sub)0.8Sn(sub)0.2)$TiO_4$세라믹스와 소결조제로서 ($B_2$$O_3$.Li$_2$O)의 첨가에 따른 마이크로파 유전특성 및 미세구조에 미치는 영향에 대하여 연구하였다. 1.0 mol.% $Sb_2$O(sub)5를 첨가하고 130$0^{\circ}C$에서 5시간 소결한 (Zr(sub)0.8Sn(sub)0.2)$TiO_4$세라믹스의 경우 ($B_2$$O_3$.Li$_2$O)첨가량 증가에 따라 치밀화 및 결정립 성장에 의해 유전상수와 Q.f값은 증가하여 첨가량이 0.35wt.%에서 최대값인 38과 59,000을 각각 나타내었으며, 0.50wt.% 이상 첨가한 경우에서는 제 2상의 생성으로 인하여 감소하였다. 1.0 mol% Sb$_2$O(sub)5와 0.35wt.% ($B_2$$O_3$.$Li_2$O)를 첨가한 (Zr(sub)0.8Sn(sub)0.2)TiO$_4$세라믹스를 125$0^{\circ}C$와 135$0^{\circ}C$에서 5시간 소결한 경우에는 각각 미반응 TiO$_2$의 존재와 과대입자성장에 의한 결정립내기공의 생성으로 인하여 마이크로파 유전특성은 저하되었다.

• 한국세라믹학회지
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• 제49권1호
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• pp.84-89
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• 2012

Attempts were made to develop a stable gray pigment at reducing atmosphere, substituting Ti in $ZrTiO_4$ with Mn, Fe, Co and Cu The pigment synthesized at $1300~1500^{\circ}C$ by solid state method with the composition of $ZrTi_{1-x-y}A_xB_yO_4$ (x = y = 0.005, 0.015, 0.035, 0.055, 0.075, 0.095, 0.115, 0.135, 0.155, 0.175 and 0.195 mole, A = Mn(III), Fe(III), Co(II, III) and Cu(II) (chromophores), B = Sb (counterion). The pigments were fired at $1400^{\circ}C$ for 3 h with substitute amount changes of Mn, Fe, Co and Cu to $ZrTiO_4$ crystals, and analyzed by Raman spectroscopy to figure out substitute limits. Results indicated 0.035 mole for Mn, 0.115 mole for Fe, 0.015 mole for Co and 0.015 mole for Cu as substitute limits, respectively. Figs. 1, 2, 3, and 4 represent each substitute pigments of Mn, Fe, Co and Cu. Synthesized pigment was applied to a lime and a lime-magnesia glaze at 7 wt% each, and fired at reducing atmosphere of $1240^{\circ}C$, soaking time 1h. Gray color was obtained with CIE-$L^*a^*b^*$ values at 44.55, -0.65, 1.19(Mn), 40.36, -0.90, 0.30(Fe), 42.63, -0.03, -1.49(Cu) and -40.79, -0.28, -0.91(Co), respectively.

• 한국세라믹학회지
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• 제24권5호
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• pp.477-483
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• 1987

Cr2O3 doped Pb(Zr0.525 Ti0.475)O3 piezoelectric ceramics were prepared from reagent grade oxide mixture, PbO, ZrO2, TiO2 and Cr2O3. Piezoelectric and aging properties of specimens were measured for various additions of Cr2O3. Generally, it has been known that aging rate decreased with Cr2O3 addition by stabilizing the domain wall. But hysteresis loops showed that the domain destabilization was occurred at high electric field (larger than 10KV/cm). In smaller additions of Cr2O3 (0-0.2mol%), aging rate increased and microcracks were created with increasing poling filed due to increasing internal stress. In larger additions of Cr2O3(0.4∼0.6mol%), aging rate decreased with increasing poling field.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.228-229
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• 2006

본 연구에서는 초음파 모터 등의 고출력 액츄에이터에 응용 가능한 $04Pb(Ni_{1/3}Nb_{2/3})O_3-6Pb(Zr_xTi_{1-x})O_3$ 조성시스템에 소결온도를 달리하여 압전, 유전특성 및 미세구조에 관해 고찰하였다. 본 조성을 $1200^{\circ}C$ 온도에서 2, 4, 6, 8시간 소결하여 시편을 제조하였으며 이의 결정구조 및 미세조직을 분석하였다. 소결시간 증가에 따라 전기기계결합계수와 기계적품질계수는 증가하였으며, 압전상수는 Zr(Zr+Ti)비 0.390까지 증가하였으나 그 이상 증가함에 따라 감소하였다. 압전특성은 $1200^{\circ}C$에서 4시간 소결한 Zr=0.390인 조성에서 ${\varepsilon}_r$ = 4487, $k_p$ = 0.72. $d_{33}$ = 710, $Q_m$ =109의 우수한 특성을 나타내었다.

• Korean Chemical Engineering Research
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• 제45권4호
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• pp.378-383
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• 2007

Zirconium titanate($Zr_xTi_{1-x}O_2$)와 같은 다성분계 금속산화물의 박막을 형성함에 있어 비교적 저온에서 박막성분 간의 정확한 조성조절이 이루어지며 균일한 박막특성을 같게 하는 새로운 박막제조 공정방법을 제시하였다. 이 공정방법은 우선 다성분계 금속산화박막을 구성하는 단성분계 금속산화막들을 적층식구조로 형성하여 적절한 열처리로 고상확산 반응을 통한 단일상 다성분계 박막을 형성하는 것을 특징으로 한다. 본 연구에서는 단성분계 산화박막층을 형성하는 방법으로 나노두께의 박막을 형성할 수 있는 능력과 두께조절성이 우수한 PRTMOCVD(pulsed rapid thermal metalorganic chemical vapor deposition) 법이 개발 적용하였다. PRTMOCVD 법으로 $ZrO_2$와 $TiO_2$ 단성분 산화막의 두께를 제어하면서 교차로 적층시킨 후 $850^{\circ}C$의 질소분위기에서 30분간 열처리를 통한 박막간의 상호확산을 통해 $Zr_xTi_{1-x}O_2$ 다성분계 산화박막을 형성하였다. 박막내의 Zr과 Ti의 조성은 $ZrO_2$와 $TiO_2$ 단성분 산화막의 두께로 조절하였다. 형성된 $Zr_xTi_{1-x}O_2$ 박막에 대한 상세한 물성을 분석하였다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1999년도 추계학술발표강연 및 논문개요집
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• pp.25-25
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• 1999