Integrated electromechanical switch and tunable capacitor and method of making the same

A electromechanical device comprising:

• a semiconductor substrate;
• a moveable beam formed on the substrate by a standard integrated process flow from at least one conductive layer and plurality of dielectric layers;
• the moveable beam being attached to the substrate at one or more points, the semiconductor substrate being selectively etched underneath the moveable beam;
• a fixed beam formed directly above the moveable beam and separated from the movable beam by an air cavity, the fixed beam being formed from at least one conductive layer, plurality of dielectric layers and at least one mechanical support layer;
• and
• an integrated circuit also formed on the substrate, the integrated circuit sensing and controlling the position of the moveable beam by controlling the voltage or current flowing to the movable beam.

A method of forming an electromechanical device comprising the steps of:

• fabricating a first beam and an integrated circuit monolithically on a semiconductor substrate using standard semiconductor process flows;
• patterning an air cavity above the first beam using a sacrificial material;
• fabricating a second beam by performing the steps of:
• depositing a first conductive material on the sacrificial material by means of sputtering or evaporation;
• patterning a sacrificial mold for a second conductive layer;
• electrodepositing a thick second conductive layer over the mold;
• removing the sacrificial mold and an excess amount of the second conductive layer underneath the mold;
• depositing and patterning a mechanical support layer on top of the device;
• patterning and etching the semiconductor substrate from a backside of the substrate;
• and
• releasing the first beam so as to be movable by removing the sacrificial material on top of the first beam.

A method of forming an electromechanical device comprising the steps of:

• fabricating a moveable beam and an integrated circuit on a semiconductor substrate using standard semiconductor process flows;
• patterning an air-gap above the movable beam using a sacrificial material;
• fabricating a fixed beam by:
• depositing a thick conductive film on the sacrificial material by means of sputtering or evaporation;
• patterning the conductive film via standard photolithography;
• and
• etching the conductive film;
• depositing and patterning a mechanical support layer on top of an area covered by the device;
• patterning and etching the semiconductor substrate from a backside of the substrate;
• and
• releasing the moveable beam by removing the sacrificial layer placed on top of the moveable beam.