Fabrication Processes and Characteristics of Microelectromechanical System Using PZT Films

Abstract

AbstractThis paper gives a brief overview of fabrication problems and solutions for microelectromechnical system (MEMS) using PZT films based on surface micromachining techniques. In addition we report characteristics of PZT films on diagnostic test structures designed to test the new bottom electrode for MEMS. PZT(53/47) films were deposited by metalorganic decomposition on a 3″ silicon wafer with Pt/Ti/TiO2/Poly-Si/Si3N4 structure in order to fabricate piezoelectric cantilever beam microaccelerometers and uncooled infrared (IR) detectors. In order to investigate the feasibility of RuO2/Ru and Pt/RuO2 conducting layers as a new bottom electrode for piezoelectric MEMS, the piezoelectric constant (d33) of the PZT films on each bottom electrode was measured. Furthermore, we show the fraction of working top electrodes among 20 total electrodes according to electrode size to investigate the stability of PZT with different bottom electrodes. These results suggest that RuO2/Ru and Pt/RuO2 are possible for bottom electrodes of MEMS.