scholarly journals Synchrotron X-ray Microdiffraction Images of Polarization Switching in Epitaxial PZT Capacitors with Pt and SrRuO3 Top Electrodes

2003 ◽  
Vol 784 ◽  
Author(s):  
Dal-Hyun Do ◽  
Dong Min Kim ◽  
Chang-Beom Eom ◽  
Eric M. Dufresne ◽  
Eric D. Isaacs ◽  
...  
Keyword(s):  
Thin Film ◽  
Bottom Electrode ◽  
Sputter Deposition ◽  
Ferroelectric Polarization ◽  
X Rays ◽  
X Ray ◽  
Pzt Film ◽  
Thin Film Capacitors ◽  
Pzt Thin Film ◽  
Switchable Polarization

ABSTRACTThe evolution of stored ferroelectric polarization in PZT thin film capacitors was imaged using synchrotron x-ray microdiffraction with a submicron-diameter focused incident x-ray beam. To form the capacitors, an epitaxial Pb(Zr,Ti)O3 (PZT) thin film was deposited on an epitaxially-grown conductive SrRuO3 (SRO) bottom electrode on a SrTiO3 (STO) (001) substrate. Polycrystalline SRO or Pt top electrodes were prepared by sputter deposition through a shadow mask and subsequent annealing. The intensity of x-ray reflections from the PZT film depended on the local ferroelectric polarization. With 10 keV x-rays, regions of opposite polarization differed in intensity by 26% in our PZT capacitor with an SRO top electrode. Devices with SRO electrodes showed just a 25% decrease in the remnant polarization after 107 switching cycles. In devices with Pt top electrodes, however, the switchable polarization decreased a by 70% after only 5×104 cycles.

PZT Thin Films Deposited by RF Magnetron Sputtering

2013 ◽  
Vol 302 ◽  
pp. 8-13
Author(s):  
Shun Fa Hwang ◽  
Wen Bin Li
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Annealing Temperature ◽  
Bottom Electrode ◽  
Rf Sputtering ◽  
Rf Magnetron Sputtering ◽  
Pzt Thin Films ◽  
Pzt Film ◽  
Pzt Thin Film

PZT thin film was fabricated by using RF-sputtering process, and platinum was used as bottom electrodes. The sputtering gases were Ar：O2＝25：0 sccm, Ar：O2＝20：5 sccm, or Ar：O2＝15：10 sccm. After sputtering, the PZT film was annealed for 5 minutes under O2 gas environment and at the temperature of 600 0C, 650 0C, 700 0C or 750 0C. To judge the quality of the deposited PZT film, its physical properties and electric properties were evaluated. The results indicate that the best crystallization temperature of PZT thin film is about 700 0C. Also, the roughness of the PZT thin film becomes larger with the increasing of annealing temperature. By adding more oxygen in the sputtering gas, one could have better crystallization of the PZT film. As for the electrical properties, the leakage current of PZT thin film increases with the increasing of annealing temperature. Furthermore, the ferroelectric property is affected by the crystallization amount of perovskite, the thickness of PZT thin film, and the diffusion situation between the bottom electrode and the PZT film.

Contribution of electrodes and microstructures to the electrical properties of Pb(Zr0.53Ti0.47)O3 thin film capacitors

1994 ◽  
Vol 9 (11) ◽  
pp. 2968-2975 ◽  
Author(s):  
H.N. Al-Shareef ◽  
A.I. Kingon ◽  
X. Chen ◽  
K.R. Bellur ◽  
O. Auciello
Keyword(s):  
Thin Film ◽  
Electrode Material ◽  
Bottom Electrode ◽  
Low Voltage ◽  
Order Effect ◽  
Major Effect ◽  
Leakage Currents ◽  
Ohmic Behavior ◽  
Thin Film Capacitors ◽  
Pzt Thin Film

Pb(Zr0.53Ti0.47)O3 (PZT) thin film capacitors have been fabricated with four electrode combinations: Pt/PZT/Pt/SiO2Si, RuO2/PZT/Pt/SiO2/Si, RuO2/PZT/RuO2/SiO2/Si, and Pt/PZT/RuO2/SiO2/Si. It is shown that polarization fatigue is determined largely by the electrode type (Pt vs RuO2), and microstructure has only a second-order effect on fatigue. If either the top or bottom electrode is platinum, significant polarization fatigue occurs. Fatigue-free capacitors are obtained only when both electrodes are RuO2. In contrast, the bottom electrode is found to have a major effect on the leakage characteristics of the PZT capacitors, presumably via microstructural modifications. Capacitors with bottom RuO2 electrodes show high leakage currents (J = 10−3-10−5 A/cm2 at 1 V) irrespective of the top electrode material. Capacitors with Pt bottom electrodes have much lower leakage currents (J = 10−8 A/cm2 at 1 V) irrespective of the top electrode material. At low voltage, the I-V curves show ohmic behavior and negligible polarity dependence for all capacitor types. At higher voltages, the leakage current is probably Schottky emission controlled for the capacitors with Pt bottom electrodes.

Problems in Thin-Film X-ray Quantification

1990 ◽  
Vol 48 (2) ◽  
pp. 458-459
Author(s):  
J N Chapman ◽  
W A P Nicholson
Keyword(s):  
Thin Film ◽  
Specimen Thickness ◽  
X Rays ◽  
Characteristic Peak ◽  
Local Composition ◽  
X Ray ◽  
Measured Ratio ◽  
Path Lengths ◽  
Composition Changes

Energy dispersive x-ray microanalysis (EDX) is widely used for the quantitative determination of local composition in thin film specimens. Extraction of quantitative data is usually accomplished by relating the ratio of the number of atoms of two species A and B in the volume excited by the electron beam (nA/nB) to the corresponding ratio of detected characteristic photons (NA/NB) through the use of a k-factor. This leads to an expression of the form nA/nB = kAB NA/NB where kAB is a measure of the relative efficiency with which x-rays are generated and detected from the two species.Errors in thin film x-ray quantification can arise from uncertainties in both NA/NB and kAB. In addition to the inevitable statistical errors, particularly severe problems arise in accurately determining the former if (i) mass loss occurs during spectrum acquisition so that the composition changes as irradiation proceeds, (ii) the characteristic peak from one of the minority components of interest is overlapped by the much larger peak from a majority component, (iii) the measured ratio varies significantly with specimen thickness as a result of electron channeling, or (iv) varying absorption corrections are required due to photons generated at different points having to traverse different path lengths through specimens of irregular and unknown topography on their way to the detector.

Measurement of d15 Shear-Mode Piezoelectric Response in PZT Thin Film

2009 ◽  
Vol 421-422 ◽  
pp. 95-98
Author(s):  
Tsuyoshi Aoki ◽  
Shigeyoshi Umemiya ◽  
Masaharu Hida ◽  
Kazuaki Kurihara
Keyword(s):  
Thin Film ◽  
Fem Analysis ◽  
Active Part ◽  
Piezoelectric Response ◽  
Small Displacement ◽  
Shear Mode ◽  
Mems Devices ◽  
Pzt Film ◽  
Pzt Thin Film ◽  
Piezoelectric Constants

Piezoelectric films using d15 shear-mode can be applied to many useful MEMS devices. The small displacement derived from the d15 shear-mode was directly observed by a SPM measurement. An isolated PZT(52/48) active part having a pair of driving Cu electrodes was processed in a 5 m-thick sputtering film. The displacement measurement of the active part and its FEM analysis suggested that the estimated d15 piezoelectric constant of the film was 590 pm/V. And, the d31 value of the film was -120 pm/V measured by a conventional cantilever method. The obtained piezoelectric constants of the PZT film are near those of bulk.

Correlations Among Degradations in Lead Zirconate Titanate thin Film Capacitors

1993 ◽  
Vol 310 ◽  
Author(s):  
In K. Yoo ◽  
Seshu B. Desu ◽  
Jimmy Xing
Keyword(s):  
Thin Film ◽  
Leakage Current ◽  
Lead Zirconate Titanate ◽  
Oxygen Vacancies ◽  
Lead Zirconate ◽  
Electrical Degradation ◽  
Zirconate Titanate ◽  
Thin Film Capacitors ◽  
Pzt Thin Film ◽  
Degradation Properties

AbstractMany attempts have been made to reduce degradation properties of Lead Zirconate Titanate (PZT) thin film capacitors. Although each degradation property has been studied extensively for the sake of material improvement, it is desired that they be understood in a unified manner in order to reduce degradation properties simultaneously. This can be achieved if a common source(s) of degradations is identified and controlled. In the past it was noticed that oxygen vacancies play a key role in fatigue, leakage current, and electrical degradation/breakdown of PZT films. It is now known that space charges (oxygen vacancies, mainly) affect ageing, too. Therefore, a quantitative ageing mechanism is proposed based on oxygen vacancy migration under internal field generated by either remanent polarization or spontaneous polarization. Fatigue, leakage current, electrical degradation, and polarization reversal mechanisms are correlated with the ageing mechanism in order to establish guidelines for simultaneous degradation control of PZT thin film capacitors. In addition, the current pitfalls in the ferroelectric test circuit is discussed, which may cause false retention, imprint, and ageing.

Characterisation of the fatigued state of ferroelectric PZT thin-film capacitors

1995 ◽  
Vol 29 (1-4) ◽  
pp. 145-148 ◽  
Author(s):  
E.L. Colla ◽  
A.L. Kholkin ◽  
D. Taylor ◽  
A.K. Tagantsev ◽  
K.G. Brooks ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Film Capacitors ◽  
Pzt Thin Film

Breakdown mechanisms in PZT thin film capacitors

1995 ◽  
Vol 11 (1-4) ◽  
pp. 269-275 ◽  
Author(s):  
In Kyeong Yoo ◽  
Chang Jung Kim ◽  
Seshu B. Desu
Keyword(s):  
Thin Film ◽  
Thin Film Capacitors ◽  
Pzt Thin Film

The Use of BaF2 Buffer Layers for the Sputter-Deposition of Ticabacuo Thin-Film Superconductors

1989 ◽  
Vol 169 ◽  
Author(s):  
K.M. Hubbard ◽  
P.N. Arendt ◽  
D.R. Brown ◽  
D.W. Cooke ◽  
N.E. Elliott ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Sputter Deposition ◽  
Buffer Layers ◽  
X Ray Diffraction ◽  
Dc Magnetron Sputtering ◽  
X Ray ◽  
Film Substrate ◽  
Ion Backscattering ◽  
Scanning Electron

AbstractThin films of the Tl‐based superconductors often have relatively poor properties because of film/substrate interdiffusion which occurs during the anneal. We have therefore investigated the use of BaF2 as a diffusion barrier. TICaBaCuO thin films were deposited by dc magnetron sputtering onto MgO <100> substrates, both with and without an evaporation‐deposited BaF2 buffer layer, and post‐annealed in a Tl over‐pressure. Electrical properties of the films were determined by four‐point probe analysis, and compositions were measured by ion‐backscattering spectroscopy. Structural analysis was performed by X‐ray diffraction and scanning electron microscopy. The BaF2 buffer layers were found to significantly improve the properties of the TICaBaCuO thin films.

Energy distribution of μd1s muonic atom and its spin states effecting on muonic X-Ray transfer yield in solid thin film method

2014 ◽  
Vol 23 (02) ◽  
pp. 1450006 ◽  
Author(s):  
R. Gheisari ◽  
M. Afshari ◽  
K. Khorshidian
Keyword(s):  
Thin Film ◽  
Energy Distribution ◽  
Muonic Atom ◽  
Rate Equations ◽  
Spin States ◽  
X Rays ◽  
X Ray ◽  
Solid Deuterium ◽  
Molecular Formation ◽  
Film Method

We have investigated the energy distribution of [Formula: see text] and its spin states (F) effecting on muonic X-ray transfer yield in the solid thin film method. Argon ( Ar ) ion has been considered as the implanted ion in solid deuterium (s D 2) layer at a temperature of T = 3 K. A kinetics model has been used, the corresponding rate equations have been constructed and our results of X-ray yield have been compared with recent measured data. The μd1s muonic atoms, which can take part in resonant molecular formation, have been separated from atoms participating in nonresonant reactions. On this basis, the integrated number of X-rays has been calculated. The results show that the effect of μd1s energy distribution on the number of X-photons is not serious, while its spin states strongly affect the muonic X-ray yield.

Sign in / Sign up

Export Citation Format

Share Document