• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.278-281
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• 1999

PLZT thin films on Pt/Ti/SiO$_2$/Si substrate were fabricated with different Thickness by pulsed laser deposition. 14/50/50 PLZT thin film showed a maximum dielectric constant value of $\varepsilon$$_{t}$=985 at 5000$\AA$, and $\varepsilon$$_{t}$=668 at 2000A. P-EI hysteresis loop of 14/50/50 PLZT thin film was slim ferroelectric. Leakage current density of 14/50/70 PLZT thin film was 10$^{-8}$ A/$\textrm{cm}^2$ at 2000$\AA$.EX>.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.118-121
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• 1999

PLZT thin films were fabricated with different energy density by pulsed laser deposition. PLZT films deposited on Pt/Ti/SiO$_2$/Sr substrate. This PLZT thin films of 5000$\AA$ thickness were crystallized at $600^{\circ}C$, 200mTorr $O_2$ pressure for 2 J/$\textrm{cm}^2$ laser energy density. 14/50/50 PLZT thin film showed a maximum dielectric constant value of $\varepsilon$$_{r}$=1289.9 P-E hysteresis loop of 14/ 50/50 PLZT thin film was slim ferroelectric. Leakage current density of 14/50/50 PLZT thin film was 10/ sup -7/=A/$\textrm{cm}^2$.>.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.10
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• pp.866-870
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• 1998

PLZT thin films were fabricated with different Zr/Ti ratios by pulsed laser deposition. PLZT films deposited on Pt/Ti/SiO$_2$/Si substrate. This PLZT thin films of 5000$\AA$ thickness were crystallized at $600^{\circ}C$, $O_2$ pressure 200m Torr. 2/55/45 PLZT thin film showed a maximum dielectric constant value of $\varepsilon$\ulcorner=1550 and dielectric loss was 0.03 at 10kHz. At 2/70/30 PLZT thin film, coercive field and remnant polarization was respectively 19[kV/cm], 8[$\mu$C/$\textrm{cm}^2$]. Raman spectroscopy results showed that the bands of spectra became broader as the amount of Zr mol% increased and two crystal phase coexisted at 2/55/45 PLZT film. Raman spectroscopy was useful for crystal structure analysis of PLZT thin films.

• Electrical & Electronic Materials
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• v.9 no.7
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• pp.668-673
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• 1996

In this paper, (P $b_{1-x}$ L $a_{x}$)(Z $r_{0.52}$ $Ti_{0.48}$) $O_{3}$ (X=0-13[at%]) thin film were prepared by the Sol-Gel method, Multiple PLZT thin films were spin-coated on the Pt/Ti/ $SiO_{2}$Si substrate. The electrical properties of the films were investigated for varying the annealing temperature. In the PLZT(11/52/48) specimens, the dielectric ocnstant of 1236 and the polarization reversal time of 460[nm] were obtained and the breakdown of the film did not occur up to 1*10$^{10}$ cycles at the voltage of 7[V] by the bipolar acceleration. The remanent polarization and coercive field decreased with increasing the content of La in the range of 0-13[at%] and thin film of the PLZT(11/52/48) showed the value of 2.56[.mu.C/c $m^{2}$] and 21.1[kV/cm], respectively.ly.y.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.5
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• pp.313-322
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• 2001

The effects of Zr/Ti concentration ratio in PLZT (10/y/z) thin films prepared by sol-gel method are investigated for the NVFRAM application. Rosette and pyrochlore phase are observed in PLZT (10/40/60) thin film and the (100) orientation, the grain size, and the surface roughness of PLZT thin films increase due to the increase of Ti amount in Zr/Ti concentration ratio. As Ti amount of Zr/Ti concentration ratio increases, the dielectric constants at 10KHz decrease from 600 to 400, while the loss tangents increase from 0.028 to 0.053 and the leakage current densities at 170 kY/cm decrease from 1.64$\times$10$^{-6}$ to 1.26$\times$10$^{-7}$ A/$\textrm{cm}^2$. In the results of hysteresis loops measured at $\pm$ 170 ㎸/cm, the remanent polarization and the coercive field increase from 6.62 to 12.86 $\mu$C/$\textrm{cm}^2$ and from 32.15 to 56.45 ㎸/cm, respectively, according to the change from 40/60 to 0/100 in Zr/Ti concentration ratio. Fatigue and retention properties also improve much as the Zr/Ti concentration ratio change from 40/60 to 0/100. After applying 10$^{9}$ square pulses with $\pm$5V, the remanent polarization of the PLZT (10/40/60) thin film decreases 50％ from the initial state while that of the PLZT (10/0/100) thin film decreases 30％. In the results of retention measurements of 10$^{5}$ s, the remanent polarization of the PLZT (10/0/100) thin film decreases only 11％ from the initial state, while that of the PLZT (10/40/60) thin film decreases 40%.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.1
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• pp.60-65
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• 2000

The structural and electrical characteristics of PLZT thin films fabricated onto Pt/Ti/SiO\ulcorner/Si substrates by a pulsed laser deposition were investigated to develop the high dielectric thin films were fabricated with different energy density by pulsed laser deposition. This PLZT thin films of 5000 thickness were crystallized at 600 $^{\circ}C$, 200 mTorr O\ulcorner pressure for 2 J/$\textrm{cm}^2$ laser energy density, the arain structure was transformed from planar to columnar grain. It was clearly noted from the SEM observations that oxygen pressured laser powers affect microstructures of the PLZT thin films. 14/50/50 PLZT this film showed a maximum dielectric constant value of $\varepsilon$\ulcorner=1289.9. P-E hysteresis loop of 14/50/50 PLZT thin film was flim ferro-electric. Leakage current density of 14/50/50 PLZT thin film was 10\ulcorner A/$\textrm{cm}^2$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.7
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• pp.535-540
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• 1998

Thin films of PLZT were prepared on indium tin oxide(ITO) coated glass substrates by sol-gel process and annealed by rapid thermal annealing(RTA) at $750^{\circ}C$ for 5 minutes. The crystal structure of PLZT thin films were investigated for a different Zr mol% content. XRD results showed that the crystallographic structure was transitted from tetragonal to rhombohedral structure as Zr mol% increased. Raman spectroscopy results showed that the bands of spectra became broader as the amount of Zr mol% increased and two crystal phase coexisted at 2/55/45 PLZT film. Raman spectroscopy was useful for crystal structure analysis of PLZT thin films.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.139-142
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• 1998

PLZT thin films were fabricated with different Zr/Ti ratios by pulsed laser deposition. PLZT films deposited on Pt/Ti/SiO$_2$/Si substrate. This PLZT thin films of 5000${\AA}$. thickness were crystallized at 600$^{\circ}C$, 200 mTorr O$_2$ press. 2/55/45 PLZT thin film showed a maximum dielectric constant value of $\varepsilon$$\_$r/=1500, and dielectric loss was 0.O$_3$. At 2/70/30 PLZT thin film, Coercive field and remnant polarization was respectively 19[kV/cm], 8[${\mu}$C/$\textrm{cm}^2$].

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.3
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• pp.609-615
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• 2005

The effects of Zr/Ti concentration ratio in PLZT (10/y/z) thin films prepared by sol-gel method are investigated for the NVFRAM application. As Ti amount of Zr/Ti concentration ratio increases, the dielectric constants at 10 kHz decrease from 550 to 400, while the loss tangents increase from 0.028 to 0.053 and the leakage current densities at 170 kV/cm decrease from $1.64\times10^{-6}$ to $1.26\times10^{-7}\;A/cm^2$. In the results of hysteresis loops measured at $\pm170kV/cm$, the remanent polarization and the coercive field increase from 6.62 to $12.86{\mu}C/cm^2$ and from 32.15 to 56.45 kV/cm, respectively, according to the change from 40/60 to 0/100 in Zr/Ti concentration ratio. Fatigue and retention properties also improve much as the Zr/Ti concentration ratio change from 40/60 to 0/100. After applying $10^9$ square pulses with $\pm5V$, the remanent polarization of the PLZT (10/40/60) thin film decreases $50\%$ from the initial state while that of the PLZT (10/0/100) thin film decreases $28\%$. In the results of retention measurements of 10s s, the remanent polarization of the PLZT (10/0/100) thin film dec.eases only $10\%$ from the initial state, while that of the PLZT (10/40/60) thin film decreases $40\%$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.4
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• pp.184-189
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• 2002

The electrical and optical properties of $(Pb_{0.91}La_{0.09})(Zr_{0.65}Ti_{0.35})O_3$(PLZT) thin films by MOCVD using ultrasonic spraying were investigated. To compensate the Pb loss by evaporation, 5 and 10 wt% of excess Pb was added to 0.2 M precursor. After deposition of films on ITO-coated glasses in oxygen atmosphere for 30 min, films were heated by in-situ RTA (rapid thermal annealing) method. When the films were heat treated at $600^{\circ}C$, perovskite single phase was obtained. The optical property of the film with 10 wt% excess Pb was excellent showing about 84 % of transmittance near 520 nm. The dielectric constant of the film was about 308 and the leakage current of the film was lower than the Pb excess 0, 5 wt% PLZT thin films.