Metal-based piezoelectric MEMS scanner mirrors composed of PZT thin films on titanium substrates

In this study, we have developed Ti-based piezoelectric MEMS scanner mirrors driven by PZT thin films. The 2 μm-thick PZT thin films were directly deposited on 50 μm-thick Ti substrates by rf-magnetron sputtering. The Ti substrates were preliminary microfabricated into the shape of the scanner mirror by wet-etching, therefore we could fabricate piezoelectric micro-actuators without conventional photolithographic process. We fabricated horizontal MEMS scanner mirrors for laser scanner displays and achieved a large mechanical tilt angle of 10.0° at high resonant frequency of 23.7 kHz by low driving voltage of 10 V_pp. The experimental results were consistent with the results of FEM simulation.