  For the past two decades piezo MEMS technology are emerging for its low power
consumption of ultrasonic sensing and actuation devices for biomedical
applications. Still researchers are facing challenges in miniaturization of
piezo-MEMS devices. But up-to-date there is no reports on achieving better
sensitivity and actuation strength properties in the same piezoelectric
material. As piezoelectric materials are anisotropic in nature, for that it is
essential to grow different textured PZT thin film on a single silicon
substrate. In the present investigation we have demonstrated the simple method
of growing different textured PZT thin film with same process condition without
introducing any buffer layer on a platinised silicon wafer by wet chemical
method. For this two types of modified bottom electrode Ti/Pt stacks have been
proposed i.e., mono- and bilayer Pt on a same silicon substrate using
lithography techniques. The texture of the PZT thin film grown on these Pt
layers shows (111) and (100) preferred orientations. The XPS surface analysis
was carried out on both Pt surfaces to investigate the anomalous behaviour of
different textured PZT on different Pt layers. The measured ferroelectric and
piezoelectric properties has shown low remanent polarization and high
piezocoefficient values for (100) oriented film as reported. The (100) oriented
film shows piezocoefficient (d33,f) value twice than that of (111) oriented PZT
thin films on a single silicon substrate.

Applied Physics;Materials Science