High Speed Piezoelectric Microscanners with Large Deflection using Mechanical Leverage Amplification

In this paper design and fabrication of high speed piezoelectric microscanners are presented. These single axis microscanners with 1 mm2 mirror area feature thin-film PZT (lead-zirconate-titanate) actuators with high piezoelectric coefficients [1] and mechanical leverage amplification to achieve large deflections. A parametric study by means of analytical modeling and FEM simulations has been performed. A SOI wafer consisting of 80 μm polysilicon and 1 μm SiO2 on 725 μm silicon wafer is used as the substrate, whereon a 2 μm thick PZT layer is deposited by magnetron sputtering applied for the piezoelectric drives. Various micromirrors with resonant frequencies up to 56 kHz and extrapolated θopt·D products up to 60 deg·mm have been designed. Prototypes with these designs have been successfully fabricated in a bulk micromachining process.