Abstract: A micromechanical capacitive accelerometer is provided from a single silicon wafer. The basic structure of the micromechanical accelerometer is etched in the wafer to form a released portion in the substrate, and the released and remaining portions of the substrate are coated with metal under conditions sufficient to form a micromechanical capacitive accelerometer. The substrate is preferably etched using reactive-ion etching for at least the first etch step in the process that forms the basic structure, although in another preferred embodiment, all etching is reactive-ion etching. The accelerometer also may comprise a signal-conditioned accelerometer wherein signal-conditioning circuitry is provided on the same wafer from which the accelerometer is formed, and VLSI electronics may be integrated on the same wafer from which the accelerometer is formed.

Abstract: A micromechanical capacitive accelerometer is provided from a single silicon wafer. The basic structure of the micromechanical accelerometer is etched in the wafer to form a released portion in the substrate, and the released and remaining portions of the substrate are coated with metal under conditions sufficient to form a micromechanical capacitive accelerometer. The substrate is preferably etched using reactive-ion etching for at least the first etch step in the process that forms the basic structure, although in another preferred embodiment, all etching is reactive-ion etching. The accelerometer also may comprise a signal-conditioned accelerometer wherein signal-conditioning circuitry is provided on the same wafer from which the accelerometer is formed, and VLSI electronics may be integrated on the same wafer from which the accelerometer is formed.

Abstract: A single-mask process for fabricating enclosed, micron-scale subsurface cavities in a single crystal silicon substrate includes the steps of patterning the substrate to form vias, etching the cavities through the vias, and sealing the vias. Single cavities of any configuration may be produced, but a preferred embodiment includes closely spaced cavity pairs. The cavities may be separated by a thin membrane, or may be merged to form an enlarged merged cavity having an overhanging bar to which electrical leads may be connected. A three-mask process for fabricating enclosed cavities with electrical contacts and electrical connections is also disclosed.

Abstract: A torsional cantilever is microfabricated for reduced size to increase its resonance frequency, increase its scanning speed, and permit fabrication of large numbers in an array to provide parallel scanning. The cantilever may incorporate a tip for highly sensitive force detection. The device preferably includes a cantilever arm and a counterbalance mounted on opposite sides of a laterally extending torsional beam fixed at its outer ends. Sensors detect rotation of the cantilever arm and may provide control of sensor locator through a feedback loop.

Abstract: A single mask, low temperature reactive ion etching process for fabricating high aspect ratio, released single crystal microelectromechanical structures independently of crystal orientation.

Abstract: A high aspect ratio field emission or tunnelling probe is fabricated utilizing a single crystal reactive etching and metallization process. The resulting field emission probes have self-aligned single crystal silicon sharp tips, high aspect ratio supporting posts for the tips, and integrated, self-aligned gate electrodes surrounding an electrically isolated from the tips. The gate electrodes are spaced from the tips by between 200 and 800 nm and metal silicide or metal can be applied on the tips to achieve emitter turn on at low operational gate voltages. The resulting tips have a high aspect ratio for use in probing various surface phenomena, and for this purpose, the probes can be mounted on or integrated in a three-dimensional translator for mechanical scanning across the surface and for focusing by adjusting the height of the emitter above the surface.

Abstract: A comb-type actuator for movable microelectromechanical structures includes first and second asymmetric sets of interdigitated fingers. Asymmetry is obtained by fabricating on set of fingers to have a greater height than the other set, or by providing electrically insulating segments in one set. Application of a voltage across the sets produces an asymmetric field between them and produces relative motion.

Abstract: 0504221609 Nanometer-scale field emitter tips are fabricated on a single crystal silicon substrate and an optically active semiconductive material is deposited on the tip. A bias voltage is connected between the semiconductor and the substrate to cause the optically active material to emit light.

Abstract: A multistable tunable electromicromechanical resonator structure incorporates electrostatic actuators which permit modification of the resonant frequency of the structure. The actuators consist of sets of opposed electrode fingers, each set having a multiplicity of spaced, parallel fingers. One set is mounted on a movable portion of the resonator structure and one set is mounted on an adjacent fixed base or substrate, with the fingers in opposed relationship and their adjacent ends spaced apart by a gap. An adjustable bias voltage across the sets of electrodes adjusts the resonant frequency of the movable structure and shifts the structure to a bistable state. Application of an alternating drive signal drives the structure to chaotic oscillation.

Abstract: A microelectromechanical micromotion amplifier generates a controlled lateral motion in response to a small deformation in the axial direction of a MEM beam or body. Lateral motion is produced by buckling of one or more long slender beams, the buckling motion being relatively large with respect to the axial motion which causes such lateral motion. The beams may be designed with a slight asymmetry to achieve gradual buckling in a desired direction. The device is capable of amplifying a driving motion in the range of 1-5 micrometers to produce a transverse motion in the range of 50-200 micrometers.

Abstract: An acoustic filter array of microelectromechanical beams each having a characteristic resonance frequency response to mechanical and/or acoustical vibration. The array divides incoming acoustic signals into a plurality of discrete spectral components, each of which may be separately detected and converted into corresponding electrical signals. The acoustic filter may be integrated onto a single crystal silicon substrate with electrical circuity for performing acoustic signal processing functions required for applications such as speech processing and simulating the physiological function of the ear.

Abstract: A single mask, low temperature reactive ion etching process for fabricating high aspect ratio, released single crystal microelectromechanical structures independently of crystal orientation.

Abstract: A single mask, low temperature reactive ion etching process for fabricating high aspect ratio, released single crystal microelectromechanical structures independently of crystal orientation.

Abstract: A high aspect ratio field emission or tunnelling probe is fabricated utilizing a single crystal reactive etching and metallization process. The resulting field emission probes have self-aligned single crystal silicon sharp tips, high aspect ratio supporting posts for the tips, and integrated, self-aligned gate electrodes surrounding an electrically isolated from the tips. The gate electrodes are spaced from the tips by between 200 and 800 nm and metal silicide or metal can be applied on the tips to achieve emitter turn on at low operational gate voltages. The resulting tips have a high aspect ratio for use in probing various surface phenomena, and for this purpose, the probes can be mounted on or integrated in a three-dimensional translator for mechanical scanning across the surface and for focusing by adjusting the height of the emitter above the surface.

Abstract: A novel apparatus and technique or characterizing materials at submicron scale and for characterizing micromechanical devices integrates test specimens with the testing device. The test specimen is a micromechanical structure made of the material to be characterized or may be a device under evaluation. A microloading instrument is a microelectromechanical structure incorporating a stable, planar frame to which is connected a multiplicity of comb-type capacitive actuators. A variable drive voltage applied across the actuator plates selectively moves the frame structure along a longitudinal axis in a controlled fashion. The frame is mounted to a fixed substrate by means of laterally extending spring arms which position the capacitor plates and guide the motion of the frame along the longitudinal axis. The micro loading instrument is calibrated by buckling a long slender beam cofabricated with the instrument.

Abstract: A process is described for manufacturing submicron, ultra-high aspect ratio microstructures using a trench-filling etch masking technique. Deep trenches are etched into a substrate, the trenches are filled with an appropriate trench-filling material, and deep etching into the substrate is carried out with the trench-filling material serving as a mask.

Abstract: A microelectromechanical compound stage microactuator assembly capable of motion along x, y, and z axes for positioning and scanning integrated electromechanical sensors and actuators is fabricated from submicron suspended single crystal silicon beams. The microactuator incorporates an interconnect system for mechanically supporting a central stage and for providing electrical connections to componants of the microactuator and to devices carried thereby. The microactuator is fabricated using a modified single crystal reactive etching and metallization process which incorporates an isolation process utilizing thermal oxidation of selected regions of the device to provide insulating segments which define conductive paths from external circuitry to the actuator components and to microelectronic devices such as gated field emitters carried by the actuator.

Abstract: A single mask, low temperature reactive ion etching process for fabricating high aspect ratio, released single crystal microelectromechanical structures independently of crystal orientation.

Abstract: A tunable electromicromechanical resonator structure incorporates an electrostatic actuator which permits reduction or enhancement of the resonant frequency of the structure. The actuator consists of two sets of opposed electrode fingers, each set having a multiplicity of spaced, parallel fingers. One set is mounted on a movable portion of the resonator structure and one set is mounted on an adjacent fixed base on substrate, with the fingers in opposed relationship and their adjacent ends spaced apart by a gap. An adjustable bias voltage across the sets of electrodes adjusts the resonant frequency of the movable structure.

Abstract: A fabrication process for vacuum microelectronic devices having multiple electrode levels includes production of a first-level electrode mask on a substrate. The mask pattern is transferred to the substrate to produce a trench surrounding an emitter which is formed by thermal oxidation. The trench is filled with tungsten to form a gate electrode surrounding the emitter, and the resulting wafer is planarized. A second-level electrode is formed on the top surface of the wafer, and is planarized. Additional levels are similarly produced, and thereafter the electrodes are released.