一种新型三谐振点电容式RF MEMS开关

给出了改进的电容式开关等效电路模型以及基于该电路模型的一种新型的多频段工作的电容式RFM EM S开关的设计和制作研究。分析表明,当开关的上电极为多支撑梁结构时,需要对传统的开关等效电路加以改进。利用新型等效电路模型进行模拟发现,通过适当的参数选择,可以获得多谐振点开关,不仅可以在多个频段适用,并且可以适用于较低频段。设计了一种可工作在X波段下的三谐振点电容式RF MEMS开关,并在高阻硅衬底上采用表面微加工工艺制备了开关样品。三谐振点开关的在片测试结果为:驱动电压为7 V,“开”态的插入损耗为0.69 dB@10.4 GHz,“关”态的隔离度为30.8 dB@10.4 GHz,其微波性能在0~13.5 GH z频段下优于类似结构的传统单谐振点开关。

A Novel 3-resonance Capacitive RF MEMS Switch

A modified equivalent circuit for capacitive RF MEMS and a novel switch design based on the modified equivalent circuit are presented. Analysis shows that the traditional RLC series circuit model is incomplete when capacitive switch has multiple support beams. Simulation results show that the multi-resonance switch can work in multiple frequency bands and has very good isolation in low frequency. A 3-resonance switch is designed and fabricated on high-resistivity silicon substrate. The actuation voltage of the fabricated 3-resonance point switch is 7 V, the insertion loss is 0.69 dB@10.4 GHz, and the isolation is 30.8 dB@10.4 GHz. The performance is far better than traditional single-resonance switch at frequency lower than 13.5 GHz.