A High Power Stress-Gradient Resilient RF MEMS Capacitive Switch

A high power-handling radio frequency (RF) microelectromechanical systems capacitive switch with low sensitivity to both in-plane stress and stress gradients is presented. The novel switch consists of four cantilever beams, which are tied together using an optimized center joint to minimize the effects of biaxial stress and stress gradients. Dimples with a thickness of 0.3 μm are used to result in an air dielectric in the down-state position, which greatly improves the reliability, while still maintaining a measured capacitance ratio of 5. The switch is capable of handling an RF power >12 W under hot switching conditions, as well as having low sensitivity to temperature variations (~20 mV/°C for V_p). Application areas are in high power reconfigurable filters, matching networks, and tunable antennas for modern communication systems.