Ferroelectric properties of PZT films on LaNiO3 bottom electrode deposited under different oxygen partial pressure

2005 ◽  
Vol 25 (12) ◽  
pp. 2253-2256 ◽  
Author(s):  
H. Kim ◽  
J.-H. Kim ◽  
W.K. Choo
Keyword(s):  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Bottom Electrode ◽  
Ferroelectric Properties ◽  
Pzt Films

Role of Oxygen Vacancies on the Ferroelectric Properties of Pzt Thin Films

1991 ◽  
Vol 243 ◽  
Author(s):  
Chi Kong Kwok ◽  
Seshu B. Desu
Keyword(s):  
Thin Films ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Vacancy Concentration ◽  
Ferroelectric Properties ◽  
Sol Gel ◽  
Low Oxygen ◽  
Partial Pressures ◽  
Pzt Films

AbstractThe properties of ferroelectric thin films can be significantly influenced by the presence of point defects. The concentration of vacancies presented in these thin films is known to be one of the key parameters causing the degradation of these films when these films are subjected to polarization reversals.To study the effects of the vacancy concentration on the ferroelectric properties, sol gel PZT films and powders were annealed in different oxygen partial pressures. For the PZT films, the reduction of oxides to pure metals was not observed even with films annealed at 2×10−5 atmosphere of oxygen partial pressure. Samples annealed at low oxygen partial pressure (for instance, 10−3 and 2×10−5 atmosphere), which has more Pb and O2 depletions and consequently has more Pb and O2 vacancies, cannot be switched easily. The ratios of coercive field after and before fatigue increase as the defect concentrations of the annealed samples increase.

The effect of oxygen partial pressure during cooling on lead zirconate titanate thin film growth by using rf magnetron sputtering method

1998 ◽  
Vol 13 (12) ◽  
pp. 3442-3448 ◽  
Author(s):  
Dong Joo Kim ◽  
Tae Song Kim ◽  
Jeon Kook Lee ◽  
Hyung Jin Jung
Keyword(s):  
Thin Film ◽  
Magnetron Sputtering ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Lead Zirconate Titanate ◽  
Rf Magnetron Sputtering ◽  
Lead Zirconate ◽  
Zirconate Titanate ◽  
Pzt Films ◽  
Grain Distribution

The lead zirconate titanate (PZT) thin film was deposited on platinized silicon wafer substrate by the rf magnetron sputtering method. In order to investigate the effect of cooling ambient, oxygen partial pressure was controlled during cooling PZT films. The PZT films cooled at lower oxygen partial pressure had perovskite phase and pyrochlore phase in both as-grown and postannealed films, but in the PZT films cooled at higher oxygen partial pressure, pyrochlore phases were not detected by XRD. As the oxygen partial pressure became lower during cooling, the capacitors had low values of remanent polarization and coercive field for as-grown films. The PZT capacitor with such a low value was recovered by postannealing in air, but its electrical properties had the same tendency before and after annealing. Microstructure was also affected by cooling ambient. Higher oxygen partial pressure on cooling reduced the number of very fine grains, and enhanced uniform grain distribution. Fatigue characteristics were also enhanced by cooling at higher oxygen partial pressure. However, the imprint was negligible irrespective of oxygen partial pressure upon cooling. The cooling procedure at higher oxygen ambients is believed to reduce the amounts of nonferroelectric second phases and oxygen vacancies. We find that oxygen partial pressure during cooling is a considerable process parameter. Therefore, care should be taken in treating the parameter after depositing films.

Ferroelectric Properties of Pb(Zr,Ti)O3 Thin Film Capacitors Made by RF Magnetron Sputtering and Heat-Treated by the Bottom Electrode Crystallization Method

2006 ◽  
Vol 514-516 ◽  
pp. 1348-1352
Author(s):  
Andréi I. Mardare ◽  
Cezarina C. Mardare ◽  
Raluca Savu
Keyword(s):  
Thin Film ◽  
Magnetron Sputtering ◽  
Bottom Electrode ◽  
Ferroelectric Properties ◽  
Electrical Contact ◽  
Rf Magnetron Sputtering ◽  
Electrical Contacts ◽  
Sem Images ◽  
Heat Treated ◽  
Pzt Films

The bottom electrode crystallization (BEC) method was applied to the crystallization of Pb(Zr,Ti)O3 (PZT) thin films deposited by RF magnetron sputtering on Pt/Ti/SiO2/Si substrates. Using a proportional-integral-differential controller, the current flowing in the Pt/Ti films provided accurately controlled Joule heating for the crystallization of the PZT films. The temperature uniformity of the heat treatments was investigated by measuring the ferroelectric properties of PZT. Platinum and tungsten wires were alternatively used as electrical contacts. Scanning electron microscopy (SEM) images were used to inspect the electrical contact regions between the platinum films and different contact wires. The PZT films showed higher remanent polarizations and lower leakage currents near the electrical contacts when Pt wires were used; the ferroelectric properties were more uniform on the PZT films heat-treated with W contact wires. The BEC method can successfully replace the more conventional means for thin film crystallization, having the advantage of being a very precise, low cost and low power consumption technique.

Effect of Bottom Electrode System on Ferroelectric Properties of Sputter Deposited PZT Capacitors

1998 ◽  
Vol 541 ◽  
Author(s):  
Kwon Hong ◽  
Yong Sik Yu ◽  
Shang Kyoo Lee
Keyword(s):  
Bottom Electrode ◽  
Perovskite Phase ◽  
Ferroelectric Properties ◽  
Electrode System ◽  
Fatigue Properties ◽  
Si Substrates ◽  
Pzt Films ◽  
Current Characteristics ◽  
Sputter Deposited ◽  
Electrode Systems

AbstractRF magnetron sputter deposited PZT films were prepared on various bottom electrode systems such as Pt/Ti/SiO2/Si, IrO2/SiO2/Si, Pt/IrO2/SiO2/Si and Ir/IrO2/SiO2/Si substrates using the ceramic PZT target with Pb1.1(Zr0.52Ti0.48)O3 composition. In order to obtain single perovskite phase, PZT films were sputter-deposited at room temperature under Ar only plasma condition followed by high temperature annealing under oxygen ambient. Regardless of the bottom electrode system, reasonable ferroelectric properties such as 2Pp, Vc could be obtained by 650°C post annealing. Their values were over 20μ C/cm2 and below ± 1.OV when drive voltage was ± 3V, respectively. Hybrid electrode system, namely, thick Pt or Ir and thin IrO2 shows good leakage current characteristics, of ∼ 10−8A/cm2. Fatigue properties of PZT capacitor depend on the test condition. However, retention after 3×104sec showed a degradation of 15% when writing voltage was −5V irrespective of bottom electrode system. Imprint characteristics also showed good results within ± 1 as a figure of merit (FOM).

Ferroelectric properties of BiFeO3 ceramics sintered under low oxygen partial pressure

2012 ◽  
Vol 60 (1) ◽  
pp. 83-87 ◽  
Author(s):  
A. Young Kim ◽  
Ye Ji Lee ◽  
Jeong Seog Kim ◽  
Seung Ho Han ◽  
Hyung-Won Kang ◽  
...  
Keyword(s):  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Ferroelectric Properties ◽  
Low Oxygen

Growth and Characterization of PbTiO3 and Pb(Zr,Ti)O3 Thin Films by MOCVD

1994 ◽  
Vol 361 ◽  
Author(s):  
Y. Gao ◽  
W. Dong ◽  
B.A. Turtle
Keyword(s):  
Thin Films ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Depth Profiling ◽  
X Ray Diffraction ◽  
X Ray ◽  
Si Substrates ◽  
Pzt Films ◽  
Uniform Composition

ABSTRACTFerroelectric PbTiO3 and Pb(Zr,Ti)O3 thin films with a perovskite structure were grown on MgO and Pt/Ti/SiO2/Si by MOCV.D. The microstructure and composition of the films were characterized by x-ray diffraction, SEM, and AES. Preferred orientation of either (111) or (100)/(001) was obtained on the Pt/Ti/SiO2/Si substrates at temperatures from 600 °C to 650 °C The preferred (111) orientation was attributed to the formation of the Pt3Ti phase in the Pt layer of the substrates, whereas the (100)/(001) orientations were inferred as the growth rate effect. AES depth profiling indicated a uniform composition through the thickness of the PZT films. However, SEM showed different topography and microstructure of the PZT films deposited in different oxygen partial pressure. Electrical properties of the PZT films appear varied as a function of the oxygen partial pressure in the reactor.

Structural and Ferroelectric Properties of Large c/a Phase Bismuth Ferrite Thin Films Prepared by Ion Beam Sputtering

2011 ◽  
Vol 1292 ◽  
Author(s):  
Seiji Nakashima ◽  
Yosuke Tsujita ◽  
Hironori Fujisawa ◽  
Jung Min Park ◽  
Takeshi Kanashima ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Domain Switching ◽  
Ion Beam ◽  
Ferroelectric Properties ◽  
Mixed Phase ◽  
Ion Beam Sputtering ◽  
Beam Sputtering

ABSTRACTBiFeO3 (BFO) thin films have been deposited on SrRuO3/SrTiO3 (001) substrate by using ion beam sputtering process. At low oxygen partial pressure of 11 m Pa, rhombohedral and large c/a mixed phase thin film have been obtained in spite of rhombohedral BFO single phase formation at high oxygen partial pressure of 73 mPa. From wide area 2θ-Ψ mappings, diffraction peaks from large c/a phase BFO thin film were obtained with the same extinction rule as those of rhombohedral BFO. Reciprocal space mappings around BFO (003) and BFO (103) spots indicate that lattice parameters of large c/a phase BFO were a = 0.381 nm and c = 0.461 nm (c/a =1.22), respectively. Moreover ferroelectric domain switching could be observed in both of rhombohedral BFO and mixed phase BFO thin films.

Effects of oxygen partial pressure on the ferroelectric properties of pulsed laser deposited Ba0.8Sr0.2TiO3 thin films

2013 ◽  
Vol 113 (3) ◽  
pp. 817-824 ◽  
Author(s):  
J. P. B. Silva ◽  
K. C. Sekhar ◽  
A. Almeida ◽  
J. Agostinho Moreira ◽  
M. Pereira ◽  
...  
Keyword(s):  
Thin Films ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Ferroelectric Properties ◽  
Pulsed Laser

Ferroelectric Properties of 15–20nm-Thick PZT Ultrathin Films Prepared by MOCVD

2002 ◽  
Vol 748 ◽  
Author(s):  
H. Nonomura ◽  
H. Fujisawa ◽  
M. Shimizu ◽  
H. Niu ◽  
K. Honda
Keyword(s):  
Electric Fields ◽  
Vapor Deposition ◽  
Ultrathin Films ◽  
Metalorganic Chemical Vapor Deposition ◽  
Bottom Electrode ◽  
Ferroelectric Properties ◽  
Hysteresis Loops ◽  
Chemical Vapor ◽  
Pzt Films ◽  
Large Leakage Current

ABSTRACTWe investigated ferroelectric properties of 20nm-thick epitaxial Pb(Zr,Ti)O3 (PZT) ultrathin films prepared on SrRuO3 (SRO)/SrTiO3 (STO) by metalorganic chemical vapor deposition (MOCVD). When SRO with terrace ledges was used as a bottom electrode, 20nm-thick PZT ultrathin films with ferroelectricity were successfully obtained. These PZT films exhibited saturated hysteresis loops with remanent polarizations (Pr) of 29–33 μC/cm2 and coercive electric fields (Ec) of 340–370 kV/cm. On the other hand, when PZT films were grown on SRO without terrace ledges, PZT films showed no saturated hysteresis loops because of large leakage current. The 15nm-thick PZT ultrathin film exhibiting unsaturated hysteresis loop was also obtained.

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