MEMS-based piezoelectric micro cantilever using LaNiO3 buffered PZT thin film

Abstract

We have fabricated piezoelectric micro cantilevers using LaNiO3 (LNO) buffered PZT thin film through microelectromechanical systems (MEMS) micro fabrication process. The micro cantilevers have been fabricated from Pt/Ti/LNO/PZT/LNO/Pt/Ti/SiO2 or Pt/Ti/PZT/Pt/Ti/SiO2 multilayers deposited on SOI wafers. The PZT thin films without LNO thin films were degraded through the MEMS micro fabrication process. We have found that the LNO thin films can avoid the degradation. DC actuation of the micro cantilevers using LNO buffered PZT thin films has resulted in symmetric butterfly curve. The transverse piezoelectric constant of LNO buffered PZT thin films (-d31 = 120 pm/V) is higher than that of the PZT thin films without LNO thin films (70 pm/V).