Large bias-induced piezoelectric response in the ferroelectric polymer P(VDF-TrFE) for MEMS resonators

Impact statement The non-linear nature of the strong electrostrictive effect observed in ferroelectric polymers was used to enhance and control its piezoelectric activity by an electric field. A large and tunable piezoelectric response was verified in polymer-based MEMS resonators, proving the ability to tailor their actuating and sensing properties. Piezoelectricity in ferroelectrics arises from electrostriction biased by their spontaneous polarisation, which can be enhanced through a bias-induced polarisation. Doing so, the piezoelectric response can be tuned and significantly enhanced. In this study, the ferroelectric polymer P(VDF-TrFE) was used to electro-mechanically excite a silicon microcantilever. Using this device, we demonstrate that a bias-induced polarisation improves the piezoelectric response of P(VDF-TrFE). To distinguish between the linear piezoelectric and quadratic electrostrictive effect, lock-in measurements were performed in order to separate the characteristic frequency response of both electro-mechanical phenomena. This work shows the potential for MEMS devices having controllable actuating and sensing properties.

Automated summary

This study successfully enhanced and controlled the piezoelectric activity of polymer-based MEMS resonators by utilizing the non-linear electrostrictive effect in ferroelectric polymers. The results demonstrate the potential for tuning and improving the piezoelectric response through bias-induced polarization, showcasing the ability to tailor actuating and sensing properties in MEMS devices.