Pzt Thin Films For Fbar Prepared

The PZT thin film with the structure of perovskite has a very great future in the microelectronic and optoelectronic area, because it has a lot of special character. For example, it has excellent piezoelectric character, excellent optoelectronic character, excellent nonlinear optical character, and so on. As a kind of piezoelectric material, PZT material owns high electromechanical coupling coefficient and high piezoelectric strain coefficient, so it has great advantage in improving the bandwidth property of FBAR device, and reducing the volume of it. So, PZT is a great choice, when we make FBAR device with wide bandwidth and low resistance.In this dissertation, we focus on the preparation of the high-quality PZT thin film. The mainly work is described in the following:1. Preparing high quality PZT thin film by RF Magnetic Sputtering Successfully. During the course, we found that atmosphere of the sputtering, status of the underlay and process of heat treatment was very important factor, which decided if we could get high quality PZT thin film or not. According to the results, we find that: Ar atmosphere is better;If we want a good state of crystallization, we should choose low temperature and the right underlay whose lattice constant is similar with the structure of perovskite;Appropriate process of heat treatment is great helpful to get piezoelectric film with the structure of perovskite. At last, our best process condition is shown below: Ar atmosphere at 1.0×10-1 Pa;During the process of the heat treatment, quickly rise and drop the temperature, the peak value of the temperature is 650°C, and preserving the temperature for 1.5 hours.2. Preparing high quality PZT thin film by Sol-Gel Successfully, both on the underlay of Pt/Ti/SiO₂/Si and ITO. Emphatically analyzing the influence of the elements of PZT on the structure and performance of PZT thin film. According to the results, we find that: the lattice constant of PZT thin film becomes bigger, when the percentage of Zr increases;There is a right value of Zr/Zr+Ti (between 45% and 50%), of which the particle size is smallest;The more the element of Zr, the higher the crystallization temperature;When the percentage of Zr below 50%, the crystallization direction is random;Oppositely the crystallization direction is preferred orientation;But when the percentage of Zr up to 65% and higher, the preferred orientation becomes unconspicuous. Innovation Points:1. The PZT piezoelectric film is used for FBAR, there are few reports in this field. The choice of the subject is fresh.;2. Because Preparing PZT thin film on the underlay of ITO is simply, we bring forward the new FBAR structure based on ITO+PZT. We haven't found such structure until now;3. Studying on RF Magnetic Sputtering. We focus on the change of the crystal structure, discussing the influence of 02 on the state of crystallization.