Self-separated PZT thick films with bulk-like piezoelectric and electromechanical properties
- PDF / 288,781 Bytes
- 5 Pages / 584.957 x 782.986 pts Page_size
- 66 Downloads / 185 Views
Benpeng Zhu Department of Biomedical Engineering and NIH Transducer Resource Center, University of Southern California, Los Angeles, California 90089-1111
Joon Hwan Lee Materials Science and Engineering Program, Texas A&M University, College Station, Texas 77843-3128
Zhenxing Bi Department of Electrical and Computer Engineering, Texas A&M University, College Station, Texas 77843-3128
Kirk Shung Department of Biomedical Engineering and NIH Transducer Resource Center, University of Southern California, Los Angeles, California 90089-1111
Qifa Zhoua) Department of Biomedical Engineering and NIH Transducer Resource Center, University of Southern California, Los Angeles, California 90089-1111
Shinichi Takeuchi Medical Engineering Course, Graduate School of Engineering, Toin University of Yokohama, Yokohama 225-8501, Japan
Bae Ho Park Division of Quantum Phases & Devices, Department of Physics, Konkuk University, Seoul 143-701, South Korea
Quanxi Jiab) Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545
Haiyan Wangc) Materials Science and Engineering Program and Department of Electrical and Computer Engineering, Texas A&M University, College Station, Texas 77843-3128 (Received 28 July 2010; accepted 1 April 2011)
Self-separated Pb(Zr0.52Ti0.48)O3 (PZT) films were processed by a hydrothermal deposition and a rapid thermal separation method, followed by a sol–gel filling and sintering process. The films possess excellent piezoelectric and electromechanical properties close to those of bulk material. The maximum remnant polarization is over 30 lC/cm2 and the electromechanical coupling factor (kt) reaches as high as 0.52. The unique microstructure characteristics of the PZT films, such as their highly dense structure, columnar grains, well-connected grain boundaries, and well-dispersed nanopores, could all contribute to the enhanced piezoelectric and electromechanical properties.
I. INTRODUCTION
Pb(Zr0.52Ti0.48)O3 (PZT) films, with their perovskite structure,1 have been extensively investigated because of their wide range of applications including microwave devices,2 microcantilever sensors,3 and medical imaging instruments.4 The fact that PZT films have higher piezoelectric activity than other piezoelectric materials such as ZnO, GaN, and AlN,5,6 makes them potential candidates Address all correspondence to these authors. a) e-mail: [email protected] b) e-mail: [email protected] c) e-mail: [email protected] DOI: 10.1557/jmr.2011.115 J. Mater. Res., Vol. 26, No. 11, Jun 14, 2011
for high frequency transducers. The desire to use high frequency transducers that operate in the frequency range of 30–150 MHz originates from the high demand in medical ultrasonic imaging to examine the eye, the skin, and the vascular structures.4 One of the keys to fabricate high frequency transducers is to process crystalline piezoelectric PZT films with a thickness of a few micrometers.7 Compared to other growth techniques such as the sol–gel process,8,9 RFmagnetron sputtering,10 and pulsed laser de
Data Loading...
