US Patent 7978045 Multi-actuation MEMS switch

A multi-actuation MEMS switch for high frequency signals includes a substrate, a heater disposed on the substrate, a co-planar waveguide disposed on a lowest metal layer, and a movable membrane including at least two metal layers, and an dielectric layer disposed between the co-planar waveguide and the movable membrane. The movable membrane is a fixed-fixed beam structure with a center indentation. When heat is generated and conducted to the movable membrane or electrostatic force is generated between the movable membrane and the co-planar waveguide or both forces are generated, the movable membrane will bend toward the co-planar waveguide. The position of the movable membrane change capacitance on signal line for switching the RF signal.