Multi-target sputtering technology of Pb(Zr,Ti)O3 thin films for electron devices

The exploration of lead zirconate titanate (PZT) as ferroelectric ceramic dates back to 1952. It has a number of superior attributes such as high piezoelectric coefficient, low dielectric loss, high resistivity, and high Curie temperature. The possibility to tailor the properties of PZT by varying Zr/Ti ratio makes it very attractive for plethora of electron devices, e. g., sensors, actuators, capacitors, and non-volatile memories. With the miniaturization of devices and the requirement of integration with Si-based CMOS processes, the complexity of fabricating PZT thin film system is continuously increasing. It in turns requires for a precise control of each and every process steps. In this volume of the book series “Dresden Contributions to Sensor Technology”, an industrial scale PZT fabrication technology for various thin film-based electron devices has been investigated. A multi-target reactive sputtering approach has been used to fabricate the functional PZT layer system on large-diameter Si wafers. Since PZT thin film properties strongly depend on the bottom layer, three different PZT systems have been investigated: PZT/ZrO2, PZT/Pt, and PZT/BaPbO3/Pt. The process optimization and the problems encountered during the fabrication of each of the layers in the PZT systems have been investigated in detail. The later is done through evaluation of structural, compositional as well as functional properties.