| Lead Zirconate Titanate (PZT) is a kind of piezoelectric smart material, with excellent piezoelectric, ferroelectric, pyroelectric properties and so on. PZT can not only exist in the form of solid, fiber and membrane, but also be made as piezoelectric composites together with other materials. It can be widely used in frequency devices, ultrasonic devices, generator components and over the control of vibration damping and noise reduction. As a kind of new material to manufacture sensors and actuators, it gets more and more attention. In this paper, the PZT thin film with optimal performance will be made as stain gauge by metal-film-metal (MFM) capacitance structure, and connected to designed circuit to get micro sensor. The new micro sensor could give characterization on the control of vibration damping and noise reduction. The conclusions of this work might provide a correlative theoretical basis for the study and application of smart micro sensor.Firstly, the precursor solution of PZT was prepared by Sol-Gel method, whose concentration was 0.3mol/L. Then, a study on the thermal evolution of the precursor solution showed the thermal annealing regulation of the PZT thin films, through thermal analysis and XRD analysis. On that basis, the process flows of conventional thermal annealing (CTA) and rapid thermal annealing (RTA) were established. Pb(Zro.53Tio.47)03 thin films were fabricated on the Pt/Ti/SiO2/Si(100) substrates by spin coating method.A series of tools, including XRD, SEM, ferroelectric analyzer, were used to characterize the crystal structure, morphology and ferroelectricity of the PZT thin films. At the same time, the influences of annealing process and thickness on the structure and performance of the films were studied. The results indicated that the PZT films prepared by CTA method showed (111) peak preferred orientation and good ferroelectricity, whose surface grain size being 40-50nm and single layer thickness within 60-70nm. By comparison, the films prepared by RTA method had orientation of (100) direction. Their surface grain sizes were 360-450nm, and their average single layer thickness became thinner and thinner. The remnant polarization Pr and coercive electric field Ec of the RTA-12 film were respectively 38μC·cm-2 and 72 kV·cm-1, which was the best one in all of the films. In addition, the increase of the thickness was beneficial to the growth of the PZT grains and enhance of the films when the annealing process have been set.According to the principle of sensor, film RTA-12 was made as strain gauge by MFM capacitance structure to connect with designed cantilever beam and A/D converter, and then a new PZT thin film micro sensor was successfully prepared. When an additional excitation was added to the cantilever beam, the sensor would transmit out the vibration decays curve of the beam through computer. Compare the curve with that simulated by computer, we can get a conclusion that the sensor we prepared was workable, and it can be used to transmit complete vibration signals.
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