Deposition and patterning technique for realization of Pb(Zr_0.52, Ti_0.48)O₃ thick film micro actuator

The deposition technology for thin PZT (Pb(Zr_0.52,Ti_0.48)O₃) layers has reached an advanced state in the application area of memory fabrication. On the other hand, the application of PZT layers for actuation of micro electromechanical system (MEMS) is not well established. A relatively thicker film is necessary for this application. Conventional preparation techniques provide poor deposition rates and the accumulated residual stress during deposition results in the deposited layer peeling off. Another difficulty lies in the low etching rate of the multilayered structure of SiO₂/Ti/Pt/PZT. These are the reasons why we have studied thick PZT film preparation technology and efficient pattering processes. Thick film deposition processes include repeated multilayer coating by the sol-gel method, the excimer laser ablation deposition (ELAD), and the jet molding system (JMS). Pattering processes include RIE, ECR and deposition methods on a non-planar surface. The electrical properties of PZT layers were determined for microfabricated actuators.