高抑制或低插损型卫星导航FBAR芯片设计

Designs of FBAR Chips for Satellite Navigation with High Rejection or Low Insertion Loss

基于6英寸(1英寸≈2.54 cm)硅基微电子机械系统(MEMS)加工工艺,采用薄膜体声波谐振器(FBAR)的结构,设计并加工了中心频率为1268.52 MHz的两款FBAR滤波器芯片,用于满足北斗卫星导航系统中不同位置的信号处理需求。通过改变电路结构和腔体面积比的方法,两款芯片分别实现了高带外抑制和低插入损耗的功能。其中高带外抑制型滤波器在近端频段可以达到50 dBc以上的带外抑制;低插入损耗型滤波器的最小插损为0.51 dB,1 dB带宽可达37 MHz以上。这两款FBAR芯片指标优异,性能稳定且一致性好,可大规模量产,较好地满足了卫星导航系统对微型滤波器的需求。

Based on the 6 inch(1 inch≈2.54 cm)silicon-based micro-electromechanical system(MEMS)processing technology and the film bulk acoustic resonator(FBAR)structure,two FBAR filter chips with a center frequency of 1268.52 MHz were designed and fabricated to meet the signal processing requirements of different positions in the Beidou satellite navigation system.By changing the circuit structure and the cavity area ratio,the two chips achieve high out-of-band rejection and low insertion loss respectively.Over 50 dBc out-of-band rejection in the near-end frequency band can be achieved by using the high out-of-band rejection filter.The minimum insertion loss of the low insertion loss filter is 0.51 dB,and the 1 dB bandwidth can achieve more than 37 MHz.These two FBAR chips have excellent indicators,stable performances and good consistency to realize large-scale mass production,which can meet the needs of micro filters for satellite navigation systems.