UV-light driven piezoelectric thin-film actuators

We fabricated UV-light driven micro-actuators utilizing epitaxial piezoelectric thin films. We prepared Pb(Zr,Ti)O
₃
(PZT) epitaxial thin films on cantilever-shaped Pt/MgO substrates, and observed light-induced deformation. When the UV-LED light was irradiated to the surface of PZT thin film, the cantilever deflected due to the coupling of photovoltaic and piezoelectric properties. The deflection of the cantilever was proportionally increased with the UV-light intensity, while the time constant was less than 2 sec, which was much shorter than that of bulk ceramics. These results indicate that UV-light driven piezoelectric thin-film actuators will open a new avenue for remote controlled micro-actuators.