Micromachined members coupled for relative rotation by hinges

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member, at least one of the torsional flexure hinges being formed by a bifilar beam;
• and
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges, the axis being located between the bifilar beam;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• drive means for imparting rotary motion to the dynamic member about the axis established by the pair of torsional flexure hinges;
• and
• at least one appendage having a first end that attaches to one of the torsional flexure hinges at a point along the torsional flexure hinge that is located between the reference member and the dynamic member, the appendage projecting outward from the torsional flexure hinge and being shaped so that upon sufficient rotation of the dynamic member about the axis with respect to the reference member a projecting end of the appendage contacts a stop having a fixed relationship with the reference member thereby stiffening a torsional spring constant of the torsional flexure hinge.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• drive means for imparting rotary motion to the dynamic member about the axis established by the pair of torsional flexure hinges;
• and
• at least one tether that is coupled at a first end to the reference member and at a second end to one of the torsional flexure hinges at a point along the torsional flexure hinge that is located between the reference member and the dynamic member whereby upon sufficient rotation of the dynamic member about the axis with respect to the reference member the tether increases a torsional spring constant of the torsional flexure hinge.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• a rotation sensor that is adapted for producing a signal responsive to angular rotation of the dynamic member about the axis with respect to the reference member;
• at least one electrode disposed adjacent to the dynamic member;
• and
• drive means for applying an electrostatic drive signal between the dynamic member and electrode that imparts rotary motion to the dynamic member about the axis established by the pair of torsional flexure hinges, the drive means receiving a signal from the rotation sensor and altering the drive signal in response thereto to improve electrostatic stability of the micromachined structure.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• the dynamic member including a reinforcing rim having a tip that is sharpened;
• at least one electrode disposed adjacent to the tip of the reinforcing rim;
• and
• drive means for applying an electrostatic drive signal between the dynamic member and electrode that imparts rotary motion to the dynamic member about the axis established by the pair of torsional flexure hinges, an electrostatic field between the reinforcing rim and the electrode produced by the drive signal being enhanced by the sharpening of the reinforcing rim.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the dynamic member including reinforcing rim;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• the reinforcing rim encircling a hollow first cavity formed into the dynamic member and
• a substrate upon which the reference member rests having a hollow second cavity formed therein that opens toward the first cavity formed into the dynamic member and that is disposed adjacent thereto.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• at least one pair of auxiliary driving-plates disposed along opposite sides of one of the pair of torsional flexure hinges between the dynamic member and the reference member, the auxiliary driving-plates being coupled to the torsional flexure hinge adjacent to the dynamic member, the pair of auxiliary driving-plates having a width perpendicular to the axis which is less than a width of the dynamic member perpendicular to the axis, the reference member, the pair of torsional flexure hinges, the dynamic member and the auxiliary driving-plate monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• at least one electrode that is disposed adjacent to one of the auxiliary driving-plates;
• and
• drive means for imparting rotary motion to the dynamic member about the axis established by the pair of torsional flexure hinges electrostatically by applying a drive signal between the auxiliary driving-plate and the electrode.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member which have a width-to-thickness (w:t) ratio that exceeds four-to-one (4:1) whereby the torsional flexure hinges exhibit increase thermal conductivity in comparison with narrower and thinner torsional flexure hinges having an equivalent torsional spring constant;
• and
• a dynamic member coupled by the torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the torsional flexure hinges;
• the reference member, the torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsion bars projecting from the reference member, at least a portion of one of the torsion bars having a width-to-length (w:l ) ratio that exceeds one-to-two (1:2) whereby the torsion bars exhibit a non-linear torsional spring constant;
• and
• a dynamic member coupled by the torsion bars to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the torsion bars and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• and
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using an isotopically pure, stress-free semiconductor layer of a silicon substrate.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• a micromachined member selected from a group consisting of the reference member and the dynamic member having at least one slot formed therein that is disposed alongside one of the torsional flexure hinges;
• and
• damping material disposed across the slot and contacting the adjacent torsional flexure hinge near the reference member.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• and
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• the dynamic member includes a stress relief cut that almost completely encircles a decoupled portion of the dynamic member thereby establishing beams for supporting that decoupled portion from a surrounding portion of the dynamic member whereby stress is decoupled between the decoupled portion and the surrounding portion.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member and at least one of the torsional flexure hinges includes a widened section;
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• and
• a torsion sensor located in the widened section that is adapted for producing a signal responsive to angular rotation of the dynamic member about the axis with respect to the reference member.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• and
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• the reference member and the dynamic member having front and back sides, and both the front and back sides of the dynamic member having a stress balanced reflective mirror coating applied thereto.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• and
• drive means for imparting rotary motion to the dynamic member about the axis established by the pair of torsional flexure hinges, the drive means initially energizing rotation of the dynamic member about the axis electro-magnetically with a current pulse to impulsively start rotation of the dynamic member to a desired orientation, the stopped dynamic member being held in the desired orientation with an electrostatic clamping force.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• and
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• the dynamic member also having a photo-detector formed therein and a wire grid polarizer disposed thereon adjacent to the photo-detector, whereby illumination incident on the photo-detector must traverse the wire grid polarizer before impinging upon the photo-detector.

An integrated, micromachined structure comprising:

• a reference member having a photo-detector formed therein adapted for detecting light scattered from an object being scanned optically;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• and
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate.

An integrated, micromachined structure comprising:

• a reference member;
• a pair of diametrically opposed torsional flexure hinges projecting from the reference member;
• and
• a dynamic member coupled by the pair of torsional flexure hinges to the reference member to be thereby supported from the reference member for rotation about an axis established by the pair of torsional flexure hinges;
• the reference member, the pair of torsional flexure hinges and the dynamic member monolithically fabricated using a stress-free semiconductor layer of a silicon substrate;
• the dynamic member also including a Fresnel lens.