Towards low-temperature deposition of piezoelectric Pb(Zr,Ti)O₃ : Influence of pressure and temperature on the properties of pulsed laser deposited Pb(Zr,Ti)O₃

Control of the structural and electrical properties of piezoelectric lead zirconate titanate (Pb(Zrx,Ti1−x)O3 -PZT) thin films is a prerequisite for successful implementation of PZT in sensor and actuator devices in microelectro-mechanical systems (MEMS). In this work, 900 nm thick PZT thin films are grown on platinized silicon wafers by pulsed laser deposition. The influence of deposition pressure and temperature on structural properties as well as on dielectric and piezoelectric properties is investigated. It is observed that PZT
thin films which possess a columnar microstructure with smooth grain boundaries, e.g. deposited at low temperature and low pressure or at high temperature and high pressure, also have high lead content. These PZT thin films exhibit higher dielectric permittivity 4r and transverse piezoelectric coefficient e31,f than films with coarse grain boundaries. We show that an e31,f of (−12.5±0.7) C/m2 can be obtained for PZT Deposition temperatures as low as 445 ◦C which can be sufficient for deposition of PZT thin films on complementary
metal-oxide-semiconductor (CMOS) wafers for MEMS actuator applications. These results provide a better understanding of the growth of PZT via pulsed laser deposition and a route to low temperature, i.e. ... mehrpost-CMOS, deposition of piezoelectric PZT thin films.