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Lead Zirconate Titanate (PZT) for M/NEMS

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Book cover Piezoelectric MEMS Resonators

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Abstract

This section concentrates on the leading ferroelectric material used in thin-film piezoelectric MEMS: lead zirconate titanate (PbZr x Ti1−x O3) or PZT. PZT-based MEMS technology has been explored extensively for a variety of actuator applications [1] but has received less attention for RF MEMS resonator and filter applications. Despite the long and successful history of bulk PZT resonators [2], the process complexity/compatibility issues and high mechanical losses have discouraged the exploitation of this strong piezoelectric for these applications. However, for select MEMS resonator and filter applications, thin-film PZT offers many unique advantages due to the high electromechanical coupling factors, permittivity, piezoelectric stress constants, and the DC-bias electric field dependence of these properties. Significant progress has also been made in developing materials deposition and processing technologies that address the fabrication challenges with PZT thin films. The goals of this section include an analysis of the deposition of these materials, patterning techniques, identification of device design and processing concerns, and finally a detailed subsection covering examples of how PZT thin films have been incorporated into resonant-based devices.

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Acknowledgment

The authors would like to thank Dr. Brett Piekarski and Dr. Paul Amirtharaj of the US Army Research Laboratory for their support and encouragement in writing this chapter. The authors also acknowledge the effort of their colleagues Dr. Sarah Bedair, Dr. Madan Dubey, Dr. Ryan Rudy, Dr. Daniel Potrepka, Dr. Luz Sanchez, Joel Martin, and Brian Power of the US Army Research Laboratory, Steven Isaacson of General Technical Services, and Dr. Glen Fox of Glen Fox Consulting in assisting with this chapter.

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Polcawich, R.G., Pulskamp, J.S. (2017). Lead Zirconate Titanate (PZT) for M/NEMS. In: Bhugra, H., Piazza, G. (eds) Piezoelectric MEMS Resonators. Microsystems and Nanosystems. Springer, Cham. https://doi.org/10.1007/978-3-319-28688-4_2

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