Using Ferroelectric Thin Film as the Dielectric for Electrowetting-on-Dielectric

Abstract

In this paper, the dielectric and electrowetting properties of Pb (Zr0.4Ti0.6)O3 (PZT) ferroelectric thin film are studied as the dielectric layer in electrowetting-on-dielectric (EWOD) device. The PZT thin film is formed by spin-coating, pyrolysis and annealing. The characterization results show that PZT thin film can serve as the dielectric of EWOD with a high dielectric constant and a great electrowetting performance when used in silicon oil bath environment. To test the electrowetting effect, a EWOD device with 200nm thick PZT ferroelectric thin film dielectric layer is fabricated. The variation of contact angle between droplet and device surface achieved with DC voltage, AC voltage and AC frequency change of electrowetting on PZT are fully experimented. The EWOD device with PZT dielectric layer can manipulate water droplet at low driving voltages. This study shows the potential of using ferroelectric ceramic material as the dielectric layer in high-performance EWOD devices.