Switching structure and method of fabrication

A bistable switch structure comprising:

• a base surface;
• a first plastic interconnect layer overlying the base surface and having a cavity extending therethrough to the base surface;
• a first patterned SMA layer overlying first plastic interconnect layer and the cavity;
• a first patterned conductive layer overlying at least a portion of the first patterned SMA layer;
• a second plastic interconnect layer overlying the first patterned conductive layer and the first patterned SMA layer;
• a second patterned SMA layer overlying the second plastic interconnect layer;
• a second patterned conductive layer overlying at least a portion of the second SMA layer;
• a fixed contact pad within the cavity and attached to the base surface and a movable contact pad attached to a portion of the first patterned SMA layer within the cavity such that when the first and second patterned SMA layers and the first and second patterned conductive layers move towards the base surface the movable contact pad touches the fixed contact pad, thereby providing an electrical connection between the movable and fixed contact pads.

A microwave switch structure comprising:

• a support layer;
• a first plastic interconnect layer overlying the support layer and having a cavity extending therethrough to the support layer;
• a transmission line on the support layer within the cavity;
• a first patterned SMA layer overlying the first plastic interconnect layer and the cavity;
• a first patterned conductive layer over at least a portion of the first patterned SMA layer;
• a second plastic interconnect layer overlying the first patterned conductive layer and the first patterned SMA layer;
• a second patterned SMA layer overlying the second plastic interconnect layer;
• a second patterned conductive layer overlying the second SMA layer,
• wherein movement of the first patterned SMA layer, the first patterned conductive layer, the second patterned SMA layer and the second conductive layer thereby change the capacitance between the transmission line and the first SMA and patterned conductive layers.