Compact electrostatic comb actuator

An electrostatic comb actuator formed on a semiconductor substrate, comprising:

• (a) a plurality of pairs of electrostatic combs in a spaced arrangement, each electrostatic comb further comprising a plurality of spaced fingers formed in a at least one layer of polysilicon and attached at one end thereof to a cross-beam formed in the at least one layer of polysilicon, with one comb of the pair being stationary, and with the other comb of the pair being moveable in response to an applied voltage to further engage the fingers of the moveable comb with the fingers of the stationary comb;
• (b) at least one restoring spring superposed with the electrostatic combs, each restoring spring being connected at one end thereof to the moveable combs to restore the moveable combs to a rest position in the absence of the applied voltage;
• and
• (c) a truss comprising a plurality of longitudinal beams oriented substantially parallel to the fingers of the electrostatic combs and attached to each moveable electrostatic comb.

An electrostatic comb actuator formed on a substrate and comprising:

• (a) a plurality of pairs of electrostatic combs formed on the substrate and having interdigitated fingers, with one electrostatic comb of each pair being stationary, and with the other electrostatic comb of each pair being moveable in response to an applied voltage to further engage the interdigitated fingers;
• (b) a truss comprising a plurality of spaced, substantially parallel beams aligned along a direction of movement of the moveable electrostatic combs to rigidly support the plurality of moveable electrostatic combs at each end thereof;
• and
• (c) a bridge attached to one end of each of the substantially parallel beams to concentrate an electrostatic force generated by the actuator.

An electrostatic comb actuator formed on a substrate and comprising:

• (a) a plurality of pairs of electrostatic combs formed on the substrate from a plurality of stacked and interconnected polycrystalline silicon layers, with the electrostatic combs having interdigitated fingers, and with one electrostatic comb of each pair of electrostatic combs being stationary and the other electrostatic comb of each pair being moveable in response to an applied voltage to further engage the interdigitated fingers;
• (b) a truss comprising a plurality of spaced, substantially parallel beams aligned along a direction of movement of the moveable electrostatic combs to support the plurality of moveable electrostatic combs at each end thereof;
• (c) a bridge attached to one end of each of the substantially parallel beams to concentrate an electrostatic force generated by the actuator;
• (d) at least one restoring spring formed from the plurality of layers of polysilicon, with the restoring spring being connected to the moveable electrostatic combs to restore the moveable electrostatic combs to a rest position in the absence of the applied voltage;
• and (e) at least one electrostatic shield located proximate to each stationary electrostatic comb.

An electrostatic comb actuator, comprising:

• (a) a substrate;
• (b) a stationary comb formed on the substrate and having a first plurality of spaced fingers extending outward from a first cross-beam;
• (c) a moveable comb formed suspended above the substrate and having a second plurality of spaced fingers extending outward from a second cross-beam and, at a rest position, partially meshing with the first plurality of spaced fingers;
• and
• (d) at least one restoring spring underlying or overlying the moveable comb, with each restoring spring being connected between the moveable comb and the substrate to return the moveable comb to the rest position upon removal of a voltage applied to the actuator to urge the moveable comb away from the rest position.

An electrostatic comb actuator formed on a substrate, comprising:

• (a) a plurality of pairs of electrostatic combs formed on the substrate from at least one layer of polycrystalline silicon, the electrostatic combs having a plurality of interdigitated fingers, with one electrostatic comb of each pair being stationary, and with the other electrostatic comb of each pair being moveable upon actuation;
• (b) a truss comprising a plurality of spaced, substantially parallel beams for rigidly supporting each moveable electrostatic comb at the ends thereof;
• and
• (c) a bridge connecting one end of each of the beams of the truss together.

An electrostatic comb actuator formed on a substrate, comprising:

• (a) a plurality of pairs of electrostatic combs formed on the substrate from at least one layer of polycrystalline silicon, the electrostatic combs having a plurality of interdigitated fingers, with one electrostatic comb of each pair being stationary, and with the other electrostatic comb of each pair being moveable upon actuation;
• (b) a truss comprising a plurality of spaced, substantially parallel beams for supporting each moveable electrostatic comb at the ends thereof;
• (c) a bridge connecting one end of each of the beams of the truss together;
• and
• (d) at least one restoring spring connected between the moveable electrostatic combs and the substrate to restore the moveable electrostatic combs to a rest position after actuation thereof, with each restoring spring underlying or overlying the moveable electrostatic combs.

An electrostatic comb actuator formed on a substrate, comprising:

• (a) a plurality of pairs of electrostatic combs formed on the substrate from at least one layer of polycrystalline silicon, the electrostatic combs having a plurality of interdigitated fingers, with one electrostatic comb of each pair being stationary, and with the other electrostatic comb of each pair being moveable upon actuation;
• (b) a truss comprising a plurality of spaced, substantially parallel beams for supporting each moveable electrostatic comb at the ends thereof;
• (c) a bridge connecting one end of each of the beams of the truss together;
• (d) at least one restoring spring connected between the moveable electrostatic combs and the substrate to restore the moveable electrostatic combs to a rest position after actuation thereof;
• and
• (e) an electrostatic shield located between each restoring spring and one of the stationary electrostatic combs for reducing an electrostatic force of attraction therebetween.

An electrostatic comb actuator formed on a substrate, comprising:

• (a) a plurality of pairs of electrostatic combs formed on the substrate from at least one layer of polycrystalline silicon, the electrostatic combs having a plurality of interdigitated fingers, with one electrostatic comb of each pair being stationary, and with the other electrostatic comb of each pair being moveable upon actuation;
• (b) a truss comprising a plurality of spaced, substantially parallel beams for supporting each moveable electrostatic comb at the ends thereof;
• (c) a bridge connecting one end of each of the beams of the truss together;
• and
• (d) an electrostatic shield located proximate to each stationary electrostatic comb.