Electromagnetic analysis and fabrication of MEMS membrane switches on GaAs substrates for X-band applications

Microelectromechanical (MEMS) switches have demonstrated great potential in microwave and millimeter-wave circuits due to their very low distortion, low power consumption, and low insertion loss characteristics. Most of switches have been fabricated on Si substrates for being familiar with the properties of Si material. In order to integrate with high-frequency GaAs signal processing circuits, it is necessary to research MEMS switches based on GaAs substrates. The MEMS membrane switches based on GaAs substrates will be introduced in this paper. Furthermore, to improve the high-frequency performance of the MEMS switch, we analyzed its electromagnetic characteristics, and developed its on-state impedance matching formula. According to the measuring results of its S-parameters, the insertion loss of the MEMS switch is less than 0.2 dB at 0.5-25.6 GHz, and the isolation can reach -42 dB at its self-resonate frequency.