Fabrication of thick Pb(Zr,Ti)O3 (PZT) films by modified sol–gel methods for application in MEMS

Lead zirconium titanate films (Pb (Zr,Ti) O3 or PZT) are being considered for potential application as dielectric films in memory technology due to their high dielectric constants. PZT is a ferroelectric material which shows spontaneous polarizability, reversible under applied electric fields. We report herein some results of TEM studies on thin film capacitor structures containing PZT films with platinum-titanium electrodes.The wafers had a stacked structure consisting of PZT/Pt/Ti/SiO2/Si substrate as shown in Figure 1. Platinum acts as electrode material and titanium is used to overcome the problem of platinum adhesion to the oxide layer. The PZT (0/20/80) films were deposited using a sol-gel method and the structure was annealed at 650°C and 800°C for 30 min in an oxygen ambient. XTEM imaging was done at 200KV with the electron beam parallel to <110> zone axis of silicon.Figure 2 shows the PZT and Pt layers only, since the structure had a tendency to peel off at the Ti-Pt interface during TEM sample preparation.

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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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A New Design of a Piezoelectric Triaxial Micro-Accelerometer

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.645-646.841 ◽

2015 ◽

Vol 645-646 ◽

pp. 841-846 ◽

Cited By ~ 1

Author(s):

Jian Yan Wang ◽

Ting Ting Wang ◽

Hang Guo

Keyword(s):

Simulation Analysis ◽

Structural Parameters ◽

Sol Gel ◽

Triaxial Accelerometer ◽

Response Frequency ◽

Pzt Films ◽

New Type ◽

The Cross ◽

Cross Axis ◽

Micro Accelerometer

Accelerometer in MEMS always is made by capacitive or piezoresistive, whose dynamic response is not good, the operating frequency is narrow, and the cross-axis sensitivity is low. A new type of piezoelectric micro-accelerometer is designed, and its structure is “x” type. The sensing unit is piezoelectric PZT films, which is achieved by sol-gel method. The accelerometer is a triaxial accelerometer. The theoretical and simulation analysis is used to achieve the charge sensitivity and response frequency, and also get the optimal structural parameters. A new circuit connection is proposed to improve the sensitivity and avoid the cross-axis sensitivity. The design achieves the z-axis sensitivity with more than 40 pC/g, x, y-axis sensitivity with more than 8pC/g, and the response frequency is about 3000Hz.

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Intermetallic Formation in PZT for MEMS Structures

MRS Proceedings ◽

10.1557/opl.2012.1404 ◽

2012 ◽

Vol 1427 ◽

Author(s):

Kanu priya Sharma ◽

Thomas Oseroff ◽

Leda Lunardi

Keyword(s):

Electron Microscopy ◽

Lead Zirconate Titanate ◽

Surface Film ◽

Sol Gel ◽

Lead Zirconate ◽

Mems Devices ◽

Aging Effects ◽

Force Microscopy ◽

Transmission Electron ◽

Pzt Films

ABSTRACTCrack free lead zirconate titanate (PZT) films for piezoelectric based MEMS devices have been prepared by a multiple coating sol gel process on platinized silicon (100) substrates. Rapid thermal annealing and Conventional furnace annealing were used for densification and crystallization of the amorphous PZT films. Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and Atomic force microscopy (AFM) were used to observe surface film morphology and grain growth. The phase content of the films was analyzed using X-ray diffraction. The role of intermetallics formed during the heat treatment in the growth of different orientations has also been observed. Film aging critical for device performance has been observed and methods to revert aging effects have been examined and discussed.

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Fabrication of Thick, Sol Gel Pzt Films: Applications to Macroscopic Piezoelectric Devices

MRS Proceedings ◽

10.1557/proc-360-103 ◽

1994 ◽

Vol 360 ◽

Cited By ~ 3

Author(s):

D.A. Barrow ◽

T.E. Petroff ◽

M. Sayer

Keyword(s):

Lead Zirconate Titanate ◽

Sol Gel ◽

Low Frequency ◽

Lead Zirconate ◽

Resonant Vibrations ◽

Pzt Film ◽

Sol Gel Process ◽

Pzt Films ◽

High Frequency Resonance ◽

Piezoelectric Devices

AbstractLead zirconate titanate (PZT) films of up to 60 μm in thickness have been fabricated on a wide variety of substrates using a new sol gel process. The dielectric properties (∈ = 900), ferroelectric (Ec = 16 kV/cm and Pr = 35 μC/cm 2) and piezoelectric properties are comparable to bulk values. The characteristic Curie point of these films is at 420 °C. Piezoelectric actuators have been developed by depositing thick PZT films on both planar and coaxial substrates. Stainless steel cantilevers and optical fibres coated with a PZT film exhibit flexure mode resonant vibrations observable with the naked eye. A low frequency in-line fibre optic modulator has been developed using a PZT coated optical fibre. The high frequency resonance of a 60 μm film on a aluminum substrate has been observed.

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Electrical and Optical Properties of Sol-Gel Processed Pb(Zr,Ti)o3 Films

MRS Proceedings ◽

10.1557/proc-271-351 ◽

1992 ◽

Vol 271 ◽

Cited By ~ 2

Author(s):

S. D. Ramamurthi ◽

S. L. Swartz ◽

K. R. Marken ◽

J. R. Busch ◽

V. E. Wood Battelle

Keyword(s):

Lead Zirconate Titanate ◽

Sol Gel ◽

Optical Characterization ◽

Solvent System ◽

Processing Parameters ◽

Lead Zirconate ◽

Electrical And Optical Properties ◽

Annealing Conditions ◽

Electro Optic ◽

Pzt Films

ABSTRACTLead-zirconate-titanate, Pb(Zr0.53Ti0.47)O3, films were produced by the sol-gel method from alkoxide and acetate precursors in a 2-methoxyethanol solvent system. The PZT films were deposited on platinized silicon and single-crystal SrTiO3 substrates for electrical and optical characterization, respectively. The processing parameters, especially excess PbO content and annealing conditions, were shown to have a significant effects on the properties of PZT films. Epitaxial PZT films deposited on SrTiO3 waveguided over 10 mm distances with propagation losses as low as 5.9 dB/cm at 783 nm and a linear electro-optic effect was also demonstrated.

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Correlation of materials and ferroelectric properties of sputtered and sol-gel PZT films

10.1109/isaf.2009.5307581 ◽

2009 ◽

Cited By ~ 1

Author(s):

R.X. Fu ◽

R. Mamazza ◽

T. S. Zheleva ◽

K.W. Kirchner ◽

B. H. Piekarski

Keyword(s):

Ferroelectric Properties ◽

Sol Gel ◽

Pzt Films

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Electrooptic Properties of Pzt thin Films for Image Storage Applications

MRS Proceedings ◽

10.1557/proc-243-73 ◽

1991 ◽

Vol 243 ◽

Cited By ~ 9

Author(s):

D. Dimos ◽

R.W. Schwartz

Keyword(s):

Thin Films ◽

Sol Gel ◽

Ferroelectric Films ◽

Image Storage ◽

Pzt Thin Films ◽

Hysteresis Behavior ◽

Pzt Films ◽

Induced Changes

AbstractThe photocurrent responses, photo-induced changes in hysteresis behavior, and electrooptic (birefringence) effects of sol-gel derived PZT films have been characterized as part of an effort to evaluate ferroelectric films for image storage and processing applications.

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