Ferroelectric thin film is the target of the interest in micro electromechanical system, memory etc. Smart MEMS is to be developed with such smart materials thin films. In spite of the success in commercialization of FRAM application, MEMS application is still under R&D state. Despite to their promising properties, there are only few reports on the use of such layers as MEMS devices. Problems for application are mainly caused by the necessary very small dimension of such devices, in contrast to limitations and tolerances of the used micro-technologies. Although deposition of piezoelectric PZTlayer using different thin-film technologies has reached an advanced state, the layers of more than 1 micron thickness needed for MEMS applications is still difficult to deposit. To deal with these problems, the structure or the function of the devices has to be coped with such technologically caused constraints, like thickness deviation and deformation by residual stress, as well as optimization of materials processing parameters. As an application of the thin films, Piezoelectric SFM and scanning mirror device are designed and fabricated as examples of the target MEMS devices with special emphases placed on materials, processing and device structure optimization. Sol gel deposited as well as Pulsed Laser Ablation Deposited PZT layers have been developed and applied for the devices. To compensate the deformation of the devices, bimorph PZT actuator is also presented. A piezoelectric SPM is expected to provide a promising answer to High density data storage devices, as the piezoelectric layer serves as a actuator for the cantilever as well as a force sensor. This paper describes a novel probe arrays integrated with micro-heaters for the AFM thermal mechanical data storage. The probes have cantilevers 3um thick, 100-200um long, and 30-70um wide, and have micro-heater integrated on the triangle end of the cantilever. The cantilever consists of a piezoelectric layer on a silicon base for the heater actuation and force sensing. The Lead-Titanate-Zirconate (PZT) is selected as the piezoelectric material for its high piezoelectric coefficients comparing to crystal materials (for example, ZnO2). We design the heater on the triangle end of the cantilever, and shape the apex part as the narrowest to get the biggest power dissipation. The prototype of the device has been fabricated and characterized.