Tactile Perceptions, Inc.

Silicon Microstructures, Inc.

Transensory Devices, Inc.

Hybond, Inc.

James W Knutti

Henry V Allen

Kurt Edward Petersen

Carl Raymond Kowalski

Stephen C Terry

Lloyd D Ingle

Methods and apparatus for an absolute or gauge pressure sensor having a backside cavity with a substantially vertical interior sidewall. The backside cavity is formed using a DRIE etch or other MEMS micro-machining technique. One embodiment provides for a diaphragm having a boss manufactured using a two step process that results in a boss thickness that is independent of the thickness of the starting material. Another provides for various shapes to the backside cavity that reduces the likelihood of crystalline fractures while focusing stress on piezoresistive sensing elements. Another provides for a sensitivity adjustment by thinning the insulating and silicon layers that form the sensor diaphragm. A pressure sensor according to the present invention may incorporate one or more of these, or may incorporate other elements discussed herein.

Extremely low cost pressure sensor realized using deep reactive ion etching

A dynamic force measurement system for taking a series of force measurements of a force applied against a sensor device whereby to determine, record, display and store the sequence of force measurements. The sensor device is adapted to respond to said force and provide an electronic force signal which is representative thereof. The dynamic force measurement system includes a central processing unit for operating a computer program, having data and program instruction storage means, graphic display and user interface means. A sensor interface device provides for the connecting of the sensor device to the central processing unit. The sensor interface device includes means for monitoring the force signal generated by the sensor device, converting the signal to a numerical binary format for recording in intermediate storage means within the sensor interface device for ultimate transfer to the central processing unit for display, statistical analysis and storage.

Dynamic force measurement system

A semiconductor transducer (10) including a substrate having a well (18) formed in one surface thereof and a semiconductor layer (14) having a first surface (26) bonded to the substrate about the periphery of the well to form a diaphragm (30) and a second surface (28) which is substantially parallel to the first surface and has a pedestal (16) projecting therefrom which is disposed above the well. The side walls (32) of the pedestal are substantially orthogonal to the second surface of the semiconductor layer and are formed by sawing edge portions of said semiconductor layer. The substrate includes structures (38) which extend upward from the bottom of the well to limit the deflection of the diaphragm.

Method of making a semiconductor transducer

A semiconductor transducer (10) including a substrate having a well (18) formed in one surface thereof and a semiconductor layer (14) having a first surface (26) bonded to the substrate about the periphery of the well to form a diaphragm (30) and a second surface (28) which is substantially coplanar to the first surface and has a pedestal (16) projecting therefrom which is disposed above the well. The side walls (32) of the pedestal are substantially orthogonal to the second surface of the semiconductor layer. Means (34) are provided for sensing the deflection of the diaphragm as a function of force applied to the pedestal. The substrate includes protrusions (38) which extend upward from the bottom of the well to limit the deflection of the diaphragm.

Semiconductor transducer

A microminiature switch for digitizing different-valued external conditions, such as pressure, temperature of acceleration, is disclosed. The switch includes a silicon wafer having a deflectable, reduced-thickness membrane adapted to move from a relaxed position toward increasingly flexed or bulged positions in response to greater-value changes in such external condition. Movement of the membrane from its relaxed position to more strained positions establishes electrical contact between a common terminal and first one and then progressively more switch-state terminals in the switch, wherein the number of switch states which are closed corresponds to the external condition acting on the switch.

Growing community of inventors

Fremont, CA, United States of America

James W Knutti