Layout design and simulation of a radio frequency bulk acoustic wave filter

Abstract:

Bulk acoustic wave filter fabricated by Complementary Metal Oxide Semiconductor(CMOS) is of high-quality factor and small size，which is better than Surface Acoustic Wave(SAW) Bulk acoustic wave filters. It has been used to take the place of conventional Radio Frequency(RF) filters for its outstanding performance and price advantage. The Modified Butterworth-Van Dyke(MBVD) model was built to analyze the frequency response of bulk acoustic wave filters. A kind of ladder RF bulk acoustic wave filter layout was designed. Based on the layout of the filter，the frequency characteristics of the varied ladder filters centering on 1.99 GHz with bandwidth 56 MHz were simulated by MBVD model and the out band attention of 4-order filter was about -29.708 dB. The tested transmission characteristics of 2-order and 3-order ladder filters fabricated by Micro Electro Mechanical Systems(MEMS) agreed well to the simulation results which indicated the broad application. The simulation results can provide a reference for designing the bulk acoustic wave filter.