6GHz高频率FBAR滤波器

6 GHz High Frequency FBAR Filter

随着5G通信的普及和移动通信技术的不断进步,薄膜体声波谐振器(FBAR)也逐渐向高频、大带宽的方向发展。基于6英寸(1英寸=2.54 cm)微电子机械系统(MEMS)工艺平台,设计并实现了一款6 GHz FBAR滤波器。通过有限元仿真与Mason模型仿真,确定了FBAR的各层厚度、谐振腔面积、电路结构等。优化了金属Mo的溅射工艺条件,通过降低靶材施加功率和增加溅射时间的方法解决了薄金属层溅射厚度不稳定、重复性差的问题。最终制备出的FBAR滤波器带内最小插入损耗为-3.4 dB,1 dB带宽可达111 MHz,近端频段带外抑制在32 dB以上,为国内高频FBAR滤波器的研制提供了参考。

With the popularization of 5 G communication and the continuous progress of mobile communication technology,film bulk acoustic resonators(FBARs)are gradually developing towards high frequency and wide bandwidth.Based on the 6 inch(1 inch=2.54 cm)micro-electromechanical system(MEMS)process platform,a 6 GHz FBAR filter was designed and processed.Through finite element simulation and Mason model simulation,the thickness of each layer,the area of the resonant cavity and the circuit structure of FBAR were determined.By reducing the target power and increasing the sputtering time,the metal Mo sputtering process conditions were optimized.The problems of unstable thickness and poor repeatability of thin metal sputtering process are solved.The final fabricated FBAR filter has a minimum in-band insertion loss of-3.4 dB,and the 1 dB bandwidth can reach 111 MHz.And the out-of-band suppression in the near-end frequency band is above 32 dB.The above work provides a reference for the development of high-frequency FBAR filters in China.