A micromachined RF microrelay with electrothermal actuation

This paper reports the design and fabrication of a low-voltage lateral-contact microrelay for RF applications. The silicon surface micromachined relay utilizes electrothermal actuators and low-stress silicon nitride as a structural connection as well as electrical and thermal isolation. The sidewall contact is sputtered gold. The driving voltage is measured to be as low as 8 V. RF testing shows that the microrelay has an off-state isolation of −20 dB at 12 GHz. The simplicity of this four-mask fabrication process provides the possibility of integration with other passive RF MEMS components.