• Journal of the Korean Ceramic Society
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• v.37 no.6
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• pp.530-536
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• 2000

During the grain growth of the PZT thin films by selective nucleation method using PZT seed, it was found that the grain size was saturated with the annealing temperature. The saturation of grain size was analyzed by the interfacial energy which appeared during the crystallization. The factors affecting the saturation of grain size were found to be the interfacial energy between perovskite phase and pyrochlore phase, and PZT thin film and the bottom Pt electrode. When the ion damage was introduced to the grain-size saturated PZT thin films, further lateral growth was observed. Pt bottom electrode thickness was changed to control the interfacial energy between the PZT thin film and the Pt bottom electrode. When Pt thickness was increased, the grain size was also increased, because the lattice parameter of Pt films was increased with the thickness of the Pt films. The incubation time of nucleation was increased with the amount of the ion damage on the Pt films.

• Journal of the Korean Ceramic Society
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• v.32 no.12
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• pp.1408-1416
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• 1995

Microstructure and ferroelectric properties of sol-gel derived PZT(52/48) and PT interlayered PZT(52/48) thin films on Pt/Ti/SiO2/Si substrates were investigated. Films were fabricated using Acetylacetone chelated PT and PZT(52/48) sols. PZT(52/48) thin films annealed at $700^{\circ}C$ for 20 min showed the rosette structure with the size of 1.2~1.6${\mu}{\textrm}{m}$ and the pyrochlore phse was contained. PT interlayered PZT thin films, which is inserted by PbTiO3 thin layer with the thickness of 130 $\AA$ between PZT thin film and electrode, consisted of a single perovskite phase after annealing above 55$0^{\circ}C$. They exhibited the uniform and columnar grains of 0.1~0.16${\mu}{\textrm}{m}$, which are applicable for microelectronic device including non-volatile memory. Typical P-E hysteresis loops could be obtained from PT interlayered PZT thin film at as low as the annealing temperature of 50$0^{\circ}C$. Ferroelectric properties of PT interlayered PZT thin films were improved as increasing annealing temperature up to $700^{\circ}C$, and then deteriorated at 75$0^{\circ}C$. PZT(52/48) and PT interlayered PZT(52/48) thin film annealed at $700^{\circ}C$ for 20 min displayed Ps=38.8$\mu$C/$\textrm{cm}^2$, Pr=10.0$\mu$C/$\textrm{cm}^2$, Ec=65.3 kV/cm and Ps=28.5$\mu$C/$\textrm{cm}^2$, Pr=9.8$\mu$C/$\textrm{cm}^2$, Ec=76.1 kV/cm, respectively.

• 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 Institute of Electrical and Electronic Material Engineers
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• v.14 no.7
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• pp.551-556
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• 2001

In this work, the recovery of etching damage in the etched PZT thin film with $O_2$ annealing has been studied. The PZT thin films were etched as a function of Cl$_2$/Ar and additive CF$_4$ into Cl$_2$(80%) /Ar(20%). the etch rates of PZT thin films were 1600$\AA$/min at Cl$_2$(80%)/Ar(20%) and 1970 $\AA$/min at 30% additive Cf$_4$ into Cl$_2$(80%)/Ar(20%). In order to recover the characteristics of etched PZT thin films, the etched PZT thin films were annealed in $O_2$ atmosphere at various temperatures. From the hysteresis curves, ferroelectrical properties are improved by $O_2$ annealing process. The improvement of ferroelectric behavior is consistent with the increase of the (100) and (200) PZT phase revealed by x-ray diffraction (XRD). From x-ray photoelectron spectroscopy (XPS) analysis, intensities of Pb-O, Zr-O and Ti-O peak increase and the chemical residue peak is reduced by $O_2$ annealing. From the atomic force microscopy (AFM) images. it shows that the surface morphology of re-annealed PZT thin films after etching is improved.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.9
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• pp.947-952
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• 2004

Tb-doped lead zirconate titanate(Pb(Zr$\_$0.6/,Ti$\_$0.4/)O$_3$; PZT) thin films on Pt(111)/Ti/SiO$_2$/Si(100) substrates were fabricated by the sol-gel method. The effect on the structural and electrical properties of films measured according to Tb content. The dielectric and ferroelectric properties of Tb-doped PZT thin films were altered significantly by Tb-doping. The PZT thin film with higher dielectric constant and improved leakage current characteristic was obtained by adding 0.3 mol% Tb. The relative dielectric constant and the dielectric loss of the 0.3 mol% Tb-doped PZT thin film were 1611 and 0.024, respectively. Typical value of the swichable remanent poaraization(2Pr) and the coercive filed of the PZT film capacitor for 0.3 mol% Tb-doped were 61.4 ${\mu}$C/cm$^2$ and 61.9 kV/cm, respectively. Tb-doped PZT thin films showed improved fatigue characteristics comparing to the undoped PZT thin film.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.109-112
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• 1999

The PZT(10/90)/(90/17) heterolayered thin films were fabricated by the spin-coaling on the Pt/Ti/SiO$_2$/Si substrate using the PZT(10/90) and PZT(70/10) metal alkoxide solutions. The effect of heterolayered thin films on the ferroelectrics and electrical properties have been investigated. The lower PZT layers provided the nucleation site for the formation of a perovskite phase of the upper PZT films. Dielectric constant increased with increasing the number of coatings, and it was about 569.9 at PZT-6 heterolayered films.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.591-596
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• 2006

Lead zirconate titanate(PZT) thin films have been attracting worldwide interests in exploring their potential properties [1-3] or the origins [4-6] of their excellent dielectic, ferroelectric and piezoelectric properties near the morphotropic phase boundary (MPB). PZT thin films are expected to apply to the memory devices, micro electro mechanical systems (MEMS), and display because of their superior ferroelectric, pyroelectric, piezoelectric and electron emission properties. In this study, high- performance piezoelectric PZT thin films for actuated mirror array and optical scanner were developed by controlling the several factors, such as molecular-designed precursor, seeding layer and the residual stress in films, by a chemical solution deposition (CSD).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.190-193
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• 2003

Sm-doped lead zirconate titanate($Pb_{1.1}(Zr_{0.6}Ti_{0.4})O_3$; PZT) thin films on the Pt(111)/Ti/$SiO_2$/Si(100) substrates prepared by a sol-gel method. The effect on structural and electrical properties of PZT thin films measured according to the Sm content. Sm-doping altered significantly dielectric and ferroelectric properties. The remanent polarization and the coercive field decreased with the increasing Sm content. The dielectric constant and the dielectric loss of PZT thin films decreased with the increasing Sm content. At 100 kHz, the dielectric constant and the dielectric loss of. the 0.3 mol% of Sm-doped PZT thin film were 1200 and 0.12 respectively. The remanent polarization (2Pr) of the 0.3 mol% of Sm-doped PZT thin film was $52.13{\mu}C/cm^2$ and the coercive field was 94.01 kV/cm. The 0.3 mol% of Sm-doped PZT thin film showed an improved fatigue characteristic comparing to the undoped PZT thin film.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1621-1623
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• 2004

The $Pb(Zr_{0.52}Ti_{0.48})O_3/(Ba_{0.6}Sr_{0.4})TiO_3$ [PZT(52/48)/BST(60/40)] heterolayered thin films were deposited on Pt/Ti/$SiO_2$/Si substrates by using the RF sputtering method with RF powers of 60,70,80,90[W]. All thin films showed the peaks of the tetragonal phase. Increasing the RF power, dielectric constant and loss of the PZT(52/48)/BST(60/40)] heterolayered thin films were decreased. The thickness ratio of PZT and BST thin films was 1/1. The relative dielectric constant and the dielectric loss of the PZT(52/48)/ BST(60/40) heterolayered thin films were 562 and 13%, respectively.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.1
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• pp.24-29
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• 2001

PZT thin films(4000A) have prepared onto 1737 corning glass and ITO coated glass substrates with a RF magnetron sputtering system using Pb_{1.05}(Zr_{0.52},Ti_{0.48})O_3$ceramic target, Electrical properties of PZT thin film deposited after ITO coated glass were P${\gamma}$ was decreased by 25% after 109cycles, respectively. With the RTA treatment duration and temperature increased, the crystallization of PZT thin films were enhanced, however, the leakage current density became higher. The leakage current mechanism was found to be space charge conduction by the defects and oxygen vacancies existing in PZT and PZT/bottom electrode interfaces.