RF Bandpass Filters using FBAR with Fractal Electrodes

In this paper, we have proposed the fractal electrodes in Film Bulk Acoustic Resonator (FBAR) and its applications in different filter configurations. The filter performance has been compared with the FBAR filters with simple conventional planar electrodes. To study the effects of fractal geometries on the performance of FBAR filters, the FEM analysis has been carried out using commercially available CoventorWare™ tool. In our analysis, we have observed that the quality factor of FBAR have been significantly enhanced by introducing specific fractal geometries in electrode. And hence, the enhancement of quality factor had led to improvement in the performance of the different filters. The extracted equivalent circuit parameters of FBAR have been used to design and simulate the filters using Agilent ADS commercial software. In this paper, the three types of different filter configurations analyzed and their response were studied.