一种射频体声波滤波器的版图设计与仿真

射频体声波滤波器品质因子高,尺寸小,其性能已超过声表面波滤波器,将其替代传统的射频滤波器极具性能和价格优势。本文建立了适用于体声波滤波器性能分析的巴特沃斯—范戴克（MBVD）模型,采用梯形级联方式设计了一种射频体声波滤波器的版图。在此基础上以中心频率为1.99GHz,带宽56MHz的体声波滤波器为例,对不同连接级数梯形滤波器的插入损耗、阻带抑制进行了仿真与分析讨论,在4阶滤波器中其带外衰减达到了-29.708dB。采用微机电机械系统工艺制备的2阶和3阶滤波器传输特性的测试曲线与仿真结果基本吻合,表明射频体声波滤波器具有广泛的应用前景。该模拟结果可作为射频体声波滤波器设计的一个重要参考。

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

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.