对适用于DC~30GHz频率的并联接触式RFMEMS开关的设计与制造进行了研究。利用低应力电镀Au桥膜作为上电极,实现了接触电极之间的Au—Au接触。使用Borofloat^TM玻璃作为衬底,并用隔离电阻对内置射频信号与驱动电极旁路进行隔离;通过对上电极桥膜与CPW间距的优化设计,使升关具有较低的插入损耗。所设计制造的并联接触式RFMEMS开关的下拉电压为60V,上下电极的接触电阻为0.1n。插入损耗为0.03dB@1GH,-0.13dB@10GHz和-0.19dB@20GHz,在Dc~30GHz的插入损耗都〈0.5dB;隔离度为-47dB@1GHz,-30dB@10GHz和25dB@20GHz,在DC30GHz的隔高度都〉~23dB。测试结果表明,所设计的并联接触式RFMEMS开关适用频率为Dc~30GHz,是一种应用频率范围较宽的RFMEMS开关。
The design and fabrication processes of a DC-contact shunt RF MEMS switch were studied to improve its performance. A low stress electroplated Au membrane was taken as an upper electrode to implement the Au Au direct contact. BorofloatTM glass was used as a substrate and a inside resistance was used to isolate the crosstalk between radio-frequency signal and bias voltage. Then,the distance between Au membrane and Coplanar Waveguide(CPW) was optimized to lower the insertion losses of the switch. Experimental results show that the contact resistance is 0.1 fl under the pull-down voltage of 60 V. The insertion losses are --0.03 dB@IGH, --0. 13 dB@10 GHz, --0. 19 dB@20 GHz in the frequency ranges from DC to 30 GHz, which is less than -- 0. 5 dB; the isolations are --47dB@l GHz, --30 dB@10 GHz and --25 dB@20 GHz in the same frequency ranges, which is all better than --23 dB. The measurement results show that the fabricated RF MEMS switch is suitable for the applications of frequency ranges from DC to 30 GHz.