Abstract: A hearing aid includes an implantable microphone, signal-processing amplifier, battery, and microactuator. An electrical signal from the microphone is amplified and processed by the amplifier before being applied to the microactuator. The microactuator is adapted for implantation in a subject at a location from which it may mechanically create vibrations in the perilymph fluid within a subject's inner ear. A transducer of the microactuator is preferably a thin circular disk, 2 to 8 mils thick, of stress-biased PLZT. Disks of this stress-biased PLZT material can be mounted as drumheads in various different ways, preferably in conjunction with a flexible diaphragm, to small threaded metal tubes, e.g. 1.4 mm in diameter and 2.0 mm long. These tubes may be implanted into a fenestration formed through the promontory adjacent to the oval window of a subject's inner ear.

Abstract: An elongated micromachined silicon hinge includes an integral four-terminal piezo voltage torsion sensor. The micromachined hinge is disposed between masses that are located at opposite ends of the hinge, and that are fabricated integrally with the hinge by micromachining. Concurrent application of a torsional force to the hinge, by rotation of the masses about the hinge's longitudinal axis, and an electric current through the hinge's silicon, generates a voltage that appears across a pair of voltage sensing electrodes.

Abstract: A monolithic single crystal Si rate-gyro consisting of in the preferred embodiment, an outer torsional frame, self resonating with a substantial amplitude, as controlled by a four-terminal piezo torsion sensor, connected to an inner frame by torsional hinges. The inner frame itself is connected to a fixed inner post, by a set of torsion hinges, defining an axis of rotation perpendicular to the first axis. Rotation of the axis of oscillation of the outer body causes the moving mass and the inner frame to tilt and oscillate at the outer frequency due to Coriolis forces, thereby periodically deforming the inner hinges in torsion. These inner hinges are likewise equipped with a four-terminal piezo voltage torsion sensor, giving an indication of the rate of rotation of the sensor. The design allows for good sensitivity, due to the substantial swing of the outer oscillator, its high moment of inertia, excellent Si spring characteristics, and excellent sensitivity of the torsional sensors.

Abstract: Forming micro-probe tips for an atomic force microscope, a scanning tunneling microscope, a beam electron emission microscope, or for field emission, by first thinning a tip of a first material, such as silicon. The tips are then reacted with a second material, such as atoms from an organic or ammonia vapor, at a temperature of about 1000.degree. C..+-.200.degree. C. and vacuum conditions for several minutes. Vapors such as methane, propane or acetylene will be converted to SiC or WC while ammonia will be converted to Si.sub.3 N.sub.4. The converted material will have different physical, chemical and electrical properties. For example, a SiC tip will be superhard, approaching diamond in hardness. Electrically conductive tips are suitable for field emission.