Flexible Thin-Film PZT Ultrasonic Transducers on Polyimide Substrates

We report flexible thin-film lead zirconate titanate (PZT)-based ultrasonic transducers on polyimide substrates. The transducers are bar resonators designed to operate in the width extension mode. The active elements are 1 µm thick PZT films that were crystallized on Si substrates at 700 °C and transferred to 5 µm thick solution-cast polyimide via dissolution of an underlying release layer. Underwater pitch–catch testing between two neighboring 100 µm × 1000 µm elements showed a 0.2 mV signal at a 1.5 cm distance for a driving voltage of 5 V peak at 9.5 MHz. With the same excitation, a 33 kPa sound pressure output at a 6 mm distance and a 32% bandwidth at −6 dB were measured by hydrophone.

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Micromachined ultrasonic transducers based on lead zirconate titanate (PZT) films

Microsystem Technologies ◽

10.1007/s00542-012-1719-2 ◽

2012 ◽

Vol 19 (2) ◽

pp. 211-218 ◽

Cited By ~ 7

Author(s):

Junhong Li ◽

Chenghao Wang ◽

Jun Ma ◽

Mengwei Liu

Keyword(s):

Lead Zirconate Titanate ◽

Lead Zirconate ◽

Ultrasonic Transducers ◽

Zirconate Titanate ◽

Pzt Films

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

Journal of Materials Research ◽

10.1557/jmr.1998.0468 ◽

1998 ◽

Vol 13 (12) ◽

pp. 3442-3448 ◽

Cited By ~ 3

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.

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Effect of La Dopant on Electrical Properties of Pb(Zr,Ti)O3 Thin Film Capacitors

MRS Proceedings ◽

10.1557/proc-596-211 ◽

1999 ◽

Vol 596 ◽

Cited By ~ 1

Author(s):

Chang Jung Kim ◽

Ilsub Chung

Keyword(s):

Thin Film ◽

Thin Films ◽

Electrical Properties ◽

Lead Zirconate Titanate ◽

Random Access ◽

Lead Zirconate ◽

Second Phase ◽

Pzt Thin Films ◽

Si Substrates ◽

Thin Film Capacitors

AbstractLanthanum doped lead zirconate titanate (PZT) thin films have been prepared on Pt/IrO2/Ir/SiO2/Si substrates to improve the ferroelectric and retention properties. The microstructure and electrical properties of the PZT capacitors were evaluated as a function of La content. The crystalline orientation was appreciably influenced by the addition of La in PZT thin films. The microstructures of films containing 0 and 0.5 mol% La were single phase perovskite, but for La = 1 mol%, a second phase was detected by SEM observation. The 0.5 mol% La doped PZT thin film capacitor showed the best ferroelectric and retention properties for ferroelectric random access memory compared to non-doped PZT.

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(001)-Oriented LaNiO3 Bottom Electrodes and (001)-Textured Ferroelectric Thin Films on LaNiO3

MRS Proceedings ◽

10.1557/proc-596-73 ◽

1999 ◽

Vol 596 ◽

Cited By ~ 4

Author(s):

Zhenshan Zhang ◽

Jeong Hwan Park ◽

Susan Trolier-McKinstry

Keyword(s):

Thin Films ◽

Lead Zirconate Titanate ◽

Sol Gel ◽

Lead Zirconate ◽

Metallic Oxide ◽

Working Pressure ◽

Si Substrates ◽

Oxide Electrodes ◽

Pzt Films ◽

Deposited Films

AbstractIn this work, highly (001)pc-oriented thin films of LaNiO3 (LNO) were deposited by DC magnetron sputtering onto Si substrates (pc = pseudocubic indices). The target powder was prepared using a molten salt technique with Na2CO3 as a flux. The final target density was greater than 85% of theoretical density. The best results were obtained when sputtering was carried out at a power of 186 W and a working pressure of 45 mtorr with a gas composition of 50% O2 + 50% Ar. The thickness of the deposited films was proportional to the sputtering time, and the growth rate was 300Å/hour. Highly (001)-oriented thin films of lead zirconate titanate Pb(Zr0.52Ti0.48)O3 (PZT) and Pb[(Mg1/3Nb2/3)0.7Ti0.3]O3 (PMN-PT) were fabricated by a sol-gel method on (001)-textured LNO metallic oxide electrodes. A remanent polarization of 12 μC/cm2 and d31 of -125 pC/N (assuming a Young's modulus of 35 GPa) were measured on the PMN-PT thin films with a thickness of 0.9 μm. This piezoelectric coefficient considerably exceeds that available from PZT films, and depends critically on the film orientation. Changes in the hysteresis loop due to externally applied stress will also be described.

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Low-Temperature Synthesis and Dielectric Properties of Single-Phase Lead Zirconate Titanate Thin Film with a Nano Particle Seeding Technique

MRS Proceedings ◽

10.1557/proc-784-c3.32 ◽

2003 ◽

Vol 784 ◽

Cited By ~ 1

Author(s):

Tomokazu Tanase ◽

Yoshio Kobayashi ◽

Takao Miwa ◽

Mikio Konno

Keyword(s):

Dielectric Properties ◽

Low Temperature ◽

Lead Zirconate Titanate ◽

Single Phase ◽

Dissipation Factor ◽

Lead Zirconate ◽

Solution Deposition ◽

Si Substrates ◽

Zirconate Titanate ◽

Pzt Films

ABSTRACTThe low temperature synthetic method, which combines chemical solution deposition and nm-seeding technique, was applied to the fabrication of lead zirconate titanate (PZT) thin films. Nano-crystallines of barium strontium titanate (BST) particles were prepared by the hydrolysis reaction of the complex alkoxides. PZT precursor solutions containing the BST particles were spin-coated on Pt/Ti/SiO2/Si substrates to film thickness of 500 − 800 nm at particle concentrations of 0–25.1 mol%, and annealed at various temperatures. Seeding of BST particles prevented the formation of pyrochlore phases, which appeared at temperatures above 400 °C in unseeded PZT films, and crystallized PZT into perovskite structures at 420 °C, which was more than 100 °C below the crystallization temperature of the unseeded PZT films. Measurement of dielectric properties at 1 kHz showed that the 25.1 mol% BST-seeded PZT films annealed at 450 °C had a dielectric constant as high as 300 with a dissipation factor of 0.05. Leakage current density of the film was less than 1×10-6 A/cm2 at applied electric field from 0 to 64 kV/cm.

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Orientation control of sol-gel-derived lead zirconate titanate film by addition of polyvinylpyrrolidone

Journal of Materials Research ◽

10.1557/jmr.2005.0109 ◽

2005 ◽

Vol 20 (4) ◽

pp. 882-888 ◽

Cited By ~ 14

Author(s):

Gun-Tae Park ◽

Chee-Sung Park ◽

Jong-Jin Choi ◽

Hyoun-Ee Kim

Keyword(s):

Lead Zirconate Titanate ◽

Sol Gel ◽

Lead Zirconate ◽

Organic Residues ◽

Si Substrates ◽

Pzt Film ◽

Oriented Film ◽

Zirconate Titanate ◽

Nucleation Sites ◽

Pzt Films

Highly (100)- and (111)-oriented lead zirconate titanate (PZT) films with a thickness of 350 nm were deposited on platinized Si substrates through a single spinning of a PZT sol containing polyvinylpyrrolidone (PVP) as an additive. The crystallographic orientation of the film was strongly influenced by pyrolysis conditions after spin coating. When the spin-coated sol was pyrolyzed at temperatures above 320 °C for relatively long periods of time (>5 min), (111)-oriented film was formed after annealing at 700 °C for 10 min. On the other hand, when the same sol was pyrolyzed at 320 °C for short periods of time (<5 min), the film was strongly oriented to the (100) direction after annealing. Organic residues derived from PVP decomposition acted as nucleation sites for the (100) oriented grains during annealing after the pyrolysis. The effective d33 of the (100)-oriented PZT film (100 pC/N) was much higher than that of the (111)-oriented film (62 pC/N) with the same thickness.

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Effect of Diameter on Longitudinal Displacement in Disk Shape 10-μm-thick Lead Zirconate Titanate Films

MRS Proceedings ◽

10.1557/proc-0902-t03-09 ◽

2005 ◽

Vol 902 ◽

Cited By ~ 2

Author(s):

Takashi Iijima ◽

Satoko Osone ◽

Yoshiro Shimojo ◽

Hirotake Okino ◽

Takashi Yamamoto

Keyword(s):

Lead Zirconate Titanate ◽

Lead Zirconate ◽

Longitudinal Displacement ◽

Disk Diameter ◽

Poling Process ◽

Si Substrates ◽

Zirconate Titanate ◽

Pzt Films ◽

Before And After ◽

Thick Lead

AbstractMicro-machined piezoelectric film devices are usually fabricated onto substrates, so that the displacement response of the film is clamped with the substrate. To investigate the longitudinal displacement behavior of 10-μm-thick lead zirconate titanate (PZT) films deposited onto Si substrates, disk shape structures with diameters of 20 to 80-μm were fabricated by an reactive ion etching (RIE) process. The polarization-field (P-E) hysteresis curves did not show a remarkable difference with decreasing the PZT disk diameter. On the other hand, unipolar driven longitudinal displacement increased, and the amount of the displacement was saturated at a diameter of 30 and 20 μm. The AFM measured longitudinal piezoelectric constants, AFM d33, were estimated in the case of before poling and after poling at 100V for 10 min. The AFM d33 for the before and after poling process were 65 and 94 pm/V for 80-μm-diameter film disk, and 153 and 315 pm/V for 20-μm-diameter film disk, respectively. The value of poled AFM d33 for 20-μm-diameter film disk was comparable to bulk PZT ceramics. These results suggest that the decrease of the disk diameter reduces the Si substrate bending related with the clamping effect between the film and substrate, and facilitates domain reorientation in the poling process. It seems that the actual piezoelectric constant of films can be estimated from the longitudinal displacement when the ratio of the PZT disk diameter, d, to the PZT film thickness, t, shows d/t < 3 for 10-μm-thick PZT films.

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Ion Beam Sputter Deposition Of Ferroelectric Oxide Thin Films

MRS Proceedings ◽

10.1557/proc-223-273 ◽

1991 ◽

Vol 223 ◽

Cited By ~ 1

Author(s):

Thomas M. Graettinger ◽

O. Auciello ◽

M. S. Ameen ◽

H. N. Al-Shareef ◽

K. Gifford ◽

...

Keyword(s):

Thin Films ◽

Lead Zirconate Titanate ◽

Growth Parameters ◽

Ion Beam ◽

Lead Zirconate ◽

Electro Optic ◽

Integrated Optical ◽

Pzt Films ◽

Ion Beam Sputter Deposition ◽

Ferroelectric Oxide

ABSTRACTFerroelectric oxide films have been studied for their potential application as integrated optical materials and nonvolatile memories. Electro-optic properties of potassium niobate (KNbO3) thin films have been measured and the results correlated to the microstructures observed. The growth parameters necessary to obtain single phase perovskite lead zirconate titanate (PZT) thin films are discussed. Hysteresis and fatigue measurements of the PZT films were performed to determine their characteristics for potential memory devices.

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Sol-Gel Derived PZT Thick Films with Nano-Sized Microstructure

MRS Proceedings ◽

10.1557/proc-748-u14.9 ◽

2002 ◽

Vol 748 ◽

Cited By ~ 1

Author(s):

C. L. Zhao ◽

Z. H. Wang ◽

W. Zhu ◽

O. K. Tan ◽

H. H. Hng

Keyword(s):

Lead Zirconate Titanate ◽

Electromechanical Coupling ◽

Thick Films ◽

Sol Gel ◽

Essential Element ◽

Processing Parameters ◽

Lead Zirconate ◽

Piezoelectric Response ◽

Coupling Coefficients ◽

Pzt Films

ABSTRACTLead zirconate titanate (PZT) films are promising for acoustic micro-devices applications because of their extremely high electromechanical coupling coefficients and excellent piezoelectric response. Thicker PZT films are crucial for these acoustic applications. A hybrid sol-gel technology has been developed as a new approach to realize simple and cost-effective fabrication of high quality PZT thick films. In this paper, PZT53/47 thick films with a thickness of 5–50 μm are successfully deposited on Pt-coated silicon wafer by using the hybrid sol-gel technology. The obtained PZT thick films are dense, crack-free, and have a nano-sized microstructure. The processing parameters of this technology have been evaluated. The microstructure of the film has been observed using field-emission scanning electron microscopy and the crystallization process has been monitored by the X-ray diffraction. The thick films thus made are good candidates for fabrication of piezoelectric diaphragm which will be an essential element of microspeaker and microphone arrays.

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PIEZOELECTRIC PROPERTIES OF PZT FILMS PREPARED BY HYDROTHERMAL METHOD

International Journal of Modern Physics B ◽

10.1142/s0217979206040404 ◽

2006 ◽

Vol 20 (25n27) ◽

pp. 3805-3810 ◽

Cited By ~ 5

Author(s):

NOBUYOSHI FUJIWARA ◽

KAZUHIRO KUSUKAWA ◽

KHAIRUNISAK ABDUL RAZAK ◽

WEI GAO

Keyword(s):

Hydrothermal Method ◽

Lead Zirconate Titanate ◽

Piezoelectric Properties ◽

Compressive Loading ◽

Pure Titanium ◽

Lead Zirconate ◽

Loading Frequency ◽

X Ray Diffraction ◽

Pzt Films ◽

Transverse Effect

Lead zirconate titanate (PZT) thin films of 5 μm thick were produced by a hydrothermal method on pure titanium substrates. ZrOCl 2-8 H 2 O , Pb ( NO 3)2 and TiO 2 were used as precursors and KOH as a promoter. The hydrothermal synthesis of PZT includes nucleation and crystal growth processes at 120°C or 140°C. The crystallization states were investigated by using scanning electron microscopy and X-Ray diffraction. Piezoelectric properties were evaluated from unimorph cantilever type actuators made of the films. The relationships between the deflection of the actuator due to piezoelectric transverse effect and applied electric field in the direction of thickness of the films showed good linearity. The output voltage from the films under cyclic compressive loading increased with increasing loading frequency, and is saturated at 10 Hz. The PZT films produced by the present methods are satisfactory as a smart material, and are better than the films produced using TiCl 4 as Ti precursor.

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