Novel Dopant Strategies for the Development of Submicron PZT Ceramics

The fabrication of submicron piezoelectric ceramics (PZT-5) with properties comparable to commercially available coarse grained materials was demonstrated in the Phase I Small Business Technology Transfer (STTR) program. This work was accomplished in collaboration with the Pennsylvania State University, through a fundamental understanding of the domain state in these materials. Specifically, novel doping and compositional strategies were correlated to a specific domain state, i.e., domain size and distribution, number of variants, and transgranular domain switching to allow the previous lower limit in grain size for piezoelectric ceramics can be reduced. These submicron grain size piezoelectric materials have the piezoelectric activity of commercially available materials but will exhibit superior mechanical properties.The Phase II STTR program will extend this work to other piezoelectric materials including PZT-5H and PZT-8. The process will then be scaled to a pilot production level and optimized to maximize yields and minimize costs. Process and quality controls will be implemented to ensure repeatability of the manufacturing process. It will be demonstrated that devices requiring further miniaturization of piezoelectric active regions such as high frequency biomedical transducers (>20mhz) and low voltage (<50 volts) multilayer actuators will greatly benefit from these new materials.