Fabrication of PZT Composite Thick Films for High Frequency Membrane Resonators
- 172 Downloads
High frequency, thickness mode resonators were fabricated using a 7 μm PZT thick film which was produced using a modified composite ceramic sol-gel process. Initial studies dealt with the integration of the PZT thick film onto the substrate. Two different diffusion barrier layers were tested, titanium oxide and zirconium oxide, in conjunction with the use of 2 types of silicon substrate (differing in the etch stop layer employed, either silicon nitride or silicon oxide). Zirconium oxide gave good results in conjunction with silicon oxide. Using these conditions, devices were produced and the acoustic properties measured for different electrode sizes ranging from 45*45 to 250*250 μm2. The best electrode size, which maximised the acoustic response and minimised the insertion loss, was found to have an area of 110*110 μm2. This device showed a resonant frequency of about 200 MHz, an effective electro-mechanical coupling coefficient of 0.29 and a Q factor of 22.
KeywordsPZT thick film resonator
Unable to display preview. Download preview PDF.
- G. Caliano, F. Galanello, A. Caronti, R. Carotenuto, and M. Pappalardo, Ultrasonics Symposium (IEEE, 2000), vol. 1, p. 963.Google Scholar
- E. Cianci, V. Foglietti, G. Caliano, and M. Pappalardo, Microelectronic Engineering, 61/62, 1025 (2002)Google Scholar
- Ferroperm—High Quality Piezoelectric Ceramic components for the electronics industry, http://www.ferroperm-piezo.com/ferroperm_material_data.xls
- P.B. Kirby, Q.X. Su, E. Komuro, Q. Zhang, M. Imura, and R.W. Whatmore, PZT Thin Film Bulk Acoustic Wave Resonator and Filters, 2001 IEEE International Frequency Control Symposium and PDA Exhibition (IEEE, Seattle, WA, USA, 2001), p. 687.Google Scholar
- F.F.C. Duval, R.A. Dorey, R.H. Haigh, and R.W. Whatmore, Stable Ti/O2/Pt Electrode Structure for Lead Containing Ferroelectric Thick Films on Silicon MEMS Structures, Thin Solid Films, 444, 235 (2003).Google Scholar
- R.A. Dorey, F.F.C. Duval, R.D. Haigh, and R.W. Whatmore, Ferroelectrics, 267, 373 (2002).Google Scholar
- N. Zhang, Z. Song, S. Xing, Q. Shen, and C. Lin, Applied Surface Science, 202, 126 (2002).Google Scholar