• Particle and aerosol research
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• v.4 no.1
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• pp.21-25
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• 2008

$Pb(Zr_{0.53}Ti_{0.47})O_3$ (PZT) was synthesized by a multiple wet dry process. Precipitates prepared from reaction between $ZrOCl_2{\cdot}8H_2O$ and $TiOCl_2$ and $NH_4OH$ in an aqueous solution was dried at $100^{\circ}C$, and calcined at $500^{\circ}C$ and $700^{\circ}C$. The mixture mixed with PbO and as-dried or calcined $Zr_{0.53}Ti_{0.47}O_4$ (ZT) powders was calcined again at 700 and $800^{\circ}C$. Well crystallized ZT and PZT were formed at even $700^{\circ}C$. PZT piezoelectric ceramics of more than 98.5% in a relative density was obtained by sintering at as low as $900^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.39 no.8
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• pp.742-749
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• 2002

The PZT thin films werre deposited on Pt/Ti/$SiO_2$/Si substrate by R. F. magnetron sputtering with $Pb_{1.1}Zr_{0.53}Ti_{0.47}O_3$ target. When interlayers(PbO, $TiO_2$, PbO/$TiO_2$) were inserted between PZT and Pt, the crystallization of the PZT thin films was considerably improved and the processing temperature was lowered. Compared to the pure PZT thin films, dielectric constant, dielectric loss and polarization properties of PZT thin films with interlayers were considerably improved. From XPS depth profile analysis, it was confirmed that PZT thin films and interlayers existed independently. In particular, PZT thin films deposited on interlayer(PbO/$TiO_2$) showed the best dielectric property (${\varepsilon}_r$=414.94, tan${\delta}$=0.0241, Pr=22${\mu}C/cm^2$).

• Journal of the Korean Ceramic Society
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• v.42 no.2 s.273
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• pp.104-109
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• 2005

To study the role of PbO as the buffer layer, Pt/PZT/PbO/Si with the MFIS structure was deposited on the p-type (100) Si substrate by the r.f. magnetron sputtering with $Pb_{1.1}Zr_{0.53}Ti_{0.47}O_3$ and PbO targets. When PbO buffer layer was inserted between the PZT thin film and the Si substrate, the crystallization of the PZT thin films was considerably improved and the processing temperature was lowered. From the result of an X-ray Photoelectron Spectroscopy (XPS) depth profile result, we could confirm that the substrate temperature for the layer of PbO affects the chemical states of the interface between the PbO buffer layer and the Si substrate, which results in the inter-diffusion of Pb. The MFIS with the PbO buffer layer show the improved electric properties including the high memory window and low leakage current density. In particular, the maximum value of the memory window is 2.0V under the applied voltage of 9V for the Pt/PZT(200 nm, $400^{\circ}C)/PbO(80 nm)/Si$ structures with the PbO buffer layer deposited at the substrate temperature of $300^{\circ}C$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1991.10a
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• pp.20-23
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• 1991

In this study, 0.05Pb(Mn$\_$1/3/Nb$\_$2/3/)O$_3$+ 0.95Pb(Zr/Ti)O$_3$+x[wt%]Cr$_2$O$_3$piezoelectric ceramics were fabricated by Hot-press method, and its structural, dielectrical, piezoelectrical properties, temperature stability and aging characteristics were investigated. Among the MPB and tetragonal compositions, the specimens with 0.2, 0.3 and 0.4 [wt%] Cr$_2$O$_3$ additive amount had the poisson ratio more than 1/3. At tetragonal phase, the aging was small, and the temperature stability was improved by Cr addition. The specimen most suitable to the HF device substrate was the one with the composition of 47/53 (Zr/Ti) an 0.4 [wt%] Cr$_2$O$_3$addition.

• Electrical & Electronic Materials
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• v.6 no.5
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• pp.436-445
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• 1993

2단계하소법에 의해 낮은 하소온도에서 미세하고도 균일한 PZT분말을 합성하였다. 우선 Zr $O_{2}$와 Ti $O_{2}$ 혼합분말을 1차하소하여 (Z $r_{0.53}$ $Ti_{0.47}$) $O_{3}$(ZTO) 분말을 합성하고 이 ZTO 고용분말에 PbO와 N $b_{2}$ $O_{5}$을 혼합한 후 650-800.deg.C에서 2시간 하소하여 PZT 분말을 합성하였는데 얻어진 분말은 고상반응법에 비해 미세할 뿐만 아니라 XRD 분석결과 710.deg.C의 낮은 하소온도에서도 PZT 단일상을 나타내었다. 2단계하소법에 의해 하소온도를 낮출 수 있는 주된 이유로는 고상반응법에서는 중간생성물인 PbTi $O_{3}$상의 생성이 수반됨으로 850.deg.C 이상 되어야만 안전한 PZT가 생성될 수 있는 점을 들 수 있다. 또 2단계하소법에 의하면 950.deg.C이하의 낮은 소결온도에서도 치밀화가 미루어지는 소결이 가능함을 알 수 있었는데 이와같이 소결온도를 낮출 수 있는 것은 고상반응법에 비해 미세한 PZT 분말을 사용하였기 때문이라 풀이된다.이된다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.94.2-94.2
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• 2012

에너지 하베스터에 적용 가능한 $0.72Pb(Zr_{0.47}Ti_{0.53})O_3-0.28Pb((Ni_{0.55}Zn_{0.45})_{1/3}Nb_{2/3})O_3$ (PPZNN) 후막세라믹의 구조적 압전 특성을 조사하였다. $850^{\circ}C$에서 하소를 마친 파우더를 72시간 볼 밀링 처리한 후, 테잎 캐스팅 공정을 이용하여 0.3mm의 두께로 PPZNN 압전 세라믹을 제조하였다. $900^{\circ}C$에서 $1200^{\circ}C$까지 다양한 온도에 소결하여 온도가 증가될수록 정방형 구조로 상전이 거동하는 모습을 보였으며, 특히 $1050^{\circ}C$에서 소결된 PPZNN후막 세라믹은 이차상이 없는 고밀도의 미세구조가 관찰되었다. $d_{33}$=440 pC/N 그리고 kp = 0.46의 우수한 압전 특성을 보였으며, 에너지 변환 성능을 나타내는 $d33{\cdot}g33$ 값은 약 $20439{\times}10^{-15}\;m^2/N$ 로 매우 우수하였다. PPZNN후막 세라믹을 유니몰프 켄틸레버 형태로 제작하여 발전 평가하였을 때 저항이 470 $k{\Omega}$에서 969 ${\mu}W$ (4930 ${\mu}W/cm^3$)로 관찰되었다. PPZNN 후막 압전 세라믹은 향후 압전에너지 하베스터 소재로 다양한 응용분야에 사용될 것으로 예상된다.

• Journal of the Korean Ceramic Society
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• v.32 no.6
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• pp.726-734
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• 1995

Pb(Zr0.53Ti0.47)O3 (PZT) ceramics having different microstructures were fabricated at low temperatures using calcined PZT powders with addition of excess PbO powder and/or ball milling. The effects of excess PbO and ball milling time on the microstructure, the sintering characteristic, and the mechanical properties of these ceramics were studied. Fine powders with average particle size of 0.38㎛ could be obtained by ball milling with 2.5 mm Ф zirconia balls for 120 hours. By the addition of 2mol% of excess PbO to these powders, it was possible to obtain well-densitified PZT ceramics at low sintering temperature of 980℃. Densification behavior of PZT was affected by the addition of excess PbO powder, while, grain growth was hardly affected by PbO addition. It was observed that Vicker's hardness decreased and fracture toughness increased with the increasing amount of PbO. At 1mol% excess PbO, it was shown that the minimum values of hardness and maximum fracture toughness were achieved. In addition, with increasing sintering time, the fracture toughness decreased and the hardness increased.

• Journal of the Korean Ceramic Society
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• v.48 no.5
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• pp.467-470
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• 2011

Pb(Zr,Ti)$O_3$ (PZT) based ceramics with superior piezoelectric properties have been extensively used in various domestic and industrial appliances. However, PZT ceramics causing environmental contamination and health problems need to be eventually replaced by any of Pb-free materials. $(Na_{0.53}K_{0.47})(Nb_{1-x}Ta_x)O_3$ (NKNT), one of Pb-free piezoelectric ceramics, has long been known but its properties are not fully understood and developed. In this study, dielectric and piezoelectric properties of Pb-free NKNT ceramics were studied with Ta substitution for B-site at x = 0~0.6. It was found that polymorphic phase transition (PPT) between orthorhombic and tetragonal phases was notably influenced by Ta substitution. The highest piezoelectric coefficient ($d_{33}$) of 284 pC/N was occurred at x = 0.45.

• The Korean Journal of Ceramics
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• v.6 no.1
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• pp.68-73
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• 2000

The effects of oxygen annealing on the carbon content in MgO thin films were investigated, MgO thin films were deposited on Si(100) substrate at different temperatures of 400 to $700^{\circ}C$ and different deposition rates of 3.4 to 11.6$\AA$/min. Using rf magnetron sputtering method. Carbon content change on the surface of MgO thin films with the oxygen annealing at different temperatures was investigated using various method. The carbon content decreased as the annealing temperature increased. $Pb(Zr_{0.53}Ti_{0.47})O_3$(PZT) thin films were deposited on the MgO/Si(100) substrates. The effects of carbon content on the phase formation and the electrical properties of PZT thin films were also investigated.

• Journal of the Korean Ceramic Society
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• v.22 no.1
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• pp.40-46
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• 1985

The effect of calcining temperature ranged from $700^{\circ}C$ to 110$0^{\circ}C$ on sintering characteristics of morphotropic $Pb(Zr_{0.53}Ti_{0.47})O_3 doped with $Nb_2O_5$ has been investigated. The ratio of sintered grain size to calcined grain size decreased as the calcining temperature increased. The hardness as well as the sintered density of the samples reached a maximum at about 90$0^{\circ}C$. The X-ray diffraction pattern of the sintered sample showed both tetragonal and rhombohedral phases. The tetragonal phases intensity increased with the calcining temperature going through a maximum at about 90$0^{\circ}C$ while the rhombohedral phase intensity remained uneffected. The both intensity were about the same at 90$0^{\circ}C$ The dielectric constant of the sintered samples reached a maximum um while the dielectric dissipation factor showed a minimum at the calcining temperature of about 100$0^{\circ}C$.