Comparative measurements of piezoelectric coefficient of PZT films by berlincourt, interferometer, and vibrometer methods

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 53; no. 12; pp. 2287 - 2293
• Main Authors: Zhaorong Huang, Qi Zhang, Corkovic, S., Dorey, R., Whatmore, R.W.
• Format: Journal Article
• Language: English
• Published: United States IEEE 01-12-2006; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Ceramics; Chemicals; Electric Impedance; Electrochemistry - methods; Electromagnetic Fields; Fabrication; Interferometers; Interferometry - methods; Lasers; Lead zirconate titanates; Materials Testing - methods; Mathematical models; Membranes, Artificial; Methods; Microelectromechanical systems; Nanostructures - chemistry; Nanostructures - radiation effects; Nanostructures - ultrastructure; Optical materials; Particle Size; Piezoelectric films; Reproducibility of Results; Sensitivity and Specificity; Sol gel process; Sputtering; Stress, Mechanical; Thick films; Titanium; Titanium compounds; Vibration; Vibration meters; Vibrometers; Zirconium
• ISSN: 0885-3010; 1525-8955
• DOI: 10.1109/TUFFC.2006.175

Chemical solution deposition (CSD) techniques were used to prepare lead zirconate (Zr) titanate (Ti) (PZT) thin films with Zr/Ti ratios of 30/70 and 52/48. Usually CSD processing is restricted to making crack-free, single-layer films of 70-nm thick, but modifications to the sol-gel process have permitted the fabrication of dense, crack-free, single layers up to 200 to 300 nm thick, which can be built-up into layers up to 3-mum thick. Thicker PZT films (>2-mum single layer) can be produced by using a composite sol-gel/ceramic process. Knowledge of the electroactive properties of these materials is essential for modeling and design of novel micro-electromechanical systems (MEMS) devices, but accurate measurement of these properties is by no means straightforward. A novel, double-beam, common-path laser interferometer has been developed to measure the longitudinal (d 33 ) piezoelectric coefficient in films; the results were compared with the values obtained by Berlincourt and laser scanning vibrometer methods. It was found that, for thin-film samples, the d 33,f values obtained from the Berlincourt method are usually larger than those obtained from the interferometer and the vibrometer methods; the reasons for this are discussed