Preparation of Functionally Combined Wafers of PZT-Si for Microdevices

Abstract

The combination of PZT ceramics with excellent ferroelectric, piezoelectric, and pyroelectric properties with Si micromachining techniques promises the creation of various microdevices including sensors and actuators. The most important technique is the preparation of functionally combined wafers of PZT ceramics and Si single crystals. Three useful techniques that are the fabrication of PZT thin films on Si, the fabrication of PZT thick films on Si and the wafer bonding of PZT and Si are discussed from the point of view of the properties and micromachining of PZT. Thin PZT films on Si are most suitable for microdevices because of their micromachining capability. Thick PZT films on Si are useful for microactuators which create a large force. The wafer bonding of PZT and Si has an advantage in that it delivers the excellent functionalities of PZT ceramics, though its micromachining is difficult.