RF MEMS activities at IMETU

The research activities on RF-MEMS devices at IMETU (Institute of Microelectronics of Tsinghua University) are presented. The RFMEMS devices investigated include micro-machined inductors, switches, voltage controlled capacitors. The recent research focus is RF-MEMS switches. Two recently developed DC-contact switches are demonstrated, one is with series configuration and another is shunt. The two types of RF MEMS switch base on the same fabrication process. Borofloat™ glass was used as substrate and a special electroplating process is used to realize the low stress bridge membrane, which assure not only the possible power handling but also a low contact resistance. High performance switches with low insertion loss and high isolation have been obtained with very long life cycle more than 100M times. The S parameters characterization shows the DC-contact series RF MEMS switch is suitable for the application of frequency range from DC to 20 GHz, and the DC-contact shunt RF MEMS switch is suitable for the application of frequency range from DC to 30 GHz..