Piezoelectric thin-film characterization for MEMS

Principles of electrical and mechanical characterization of piezoelectric thin films are discussed. Both large- and small-signal measurements are presented for AlN (aluminum nitride) and PZT (lead zirconate titanate) films. Additionally, precision aspects and tolerances are addressed for typical measurement set-ups such as in Double-Beam Laser Interferometry and four-point bending test methods. To conclude, the authors discuss possibilities of wafer level vs. single test structure characterization.