Ic Sensors Inc.

Silicon Microstructures, Inc.

Leland Stanford Junior University

Microsensor Technology

Transensory Device, Inc.

Stephen C Terry

John H Jerman

Henry V Allen

Justin F Gaynor

Holger Doering

Omar Abed

Fernando Alfaro

Diederik W De Bruin

James W Knutti

Pressure sensors and associated structures that may have reduced light sensitivity. An example may provide structures reducing light at a component on a membrane of a pressure sensor.

Light shields for catheter sensors

Pressure sensors and associated structures that may facilitate the use of automated connection processes and tools. An example may provide structures for aligning interconnect wires to pressure sensor bondpads in order to facilitate the use of automated processes and tools.

Manufacturing catheter sensors

Pressure sensors and their methods of manufacturing, where the pressure sensors have a small, thin form factor and may include features designed to improve manufacturability and where the method of manufacturing may improve yield and reduce overall costs.

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

An apparatus and method of operation for a self-testable accelerometer having a housing, a diaphragm for detecting movement in response to an applied force, a mass on the diaphragm, at least one capacitive plate attached to the housing and disposed such that a potential difference between the capacitive plate and the mass causes a movement of the mass, means for producing a potential difference between the mass and the capacitive plate, and at least one piezoresistive element attached to the housing and the diaphragm for sensing movement of the mass. The accelerometer's housing comprises a frame, a base and a cap with air gaps providing squeeze film damping and mechanical stops for inhibiting movements of the mass. The combination of the capability to electrostatically produce a movement of the mass and the piezoresistive sensing of that movement allows testing and calibration of the accelerometer at any stage in its manufacture or deployment without the need for external equipment such as shakers.

Self-testable micro-accelerometer and method

An apparatus and method of operation for a self-testable accelerometer having a housing, a diaphragm for detecting movement in response to an applied force, a mass on the diaphragm, at least one capacitive plate attached to the housing and disposed such that a potential difference between the capacitive plate and the mass causes a movement of the mass, electrodes for applying a potential difference between the mass and the capacitive plate, and at least one piezoresistive element attached to the housing and the diaphragm for sensing movement of the mass. The accelerometer's housing comprises a frame, a base and a cap with air gaps providing squeeze film damping and mechanical stops for inhibiting movements of the mass. The combination of the capability to electrostatically produce a movement of the mass and the piezoresistive sensing of that movement allows testing and calibration of the accelerometer at any stage in its manufacture or deployment without the need for external equipment such as shakers.

Self-testable micro-accelerometer

A transducer having a plurality of sensing elements disposed in a single diaphragm wherein each of the sensing elements is spaced from every other of the sensing elements a predetermined distance so as to control interference among the sensing elements. Each of the sensing elements preferably comprises a plurality of piezoresistors each of which are coupled in a Wheatstone bridge configuration. This transducer achieves sensitive, accurate, high spatial resolution measurements of non-uniform pressures.

Single diaphragm transducer with multiple sensing elements

A trimmable microminiature force-sensitive switching device for detecting the state of external conditions, such as pressure, acceleration and temperature, is disclosed. The device includes a silicon substrate having a reduced-thickness, deflectable member adapted to change its deflection in response to changes in the external condition to be detected. Increasing deflection of the member establishes electrical contact between a common contact and first one, then progressively more, spaced electrical contacts of a plurality of switches. Each of the spaced electrical contacts is connected to a common terminal. Trimming of the switching device is accomplished by application of a preselected external force, such as pressure, that causes the deflection of the deflectable member and the closing of one or more of the switches. Electrical energy is then applied to the external terminal of the common contact and the external terminal of the common terminal of the fusible links, such that current flows through the switches that have closed and through their associated fusible links, causing those fusible links to open circuit, thereby precluding the subsequent detection of external conditions whose level is at or below the preselected level applied during trimming of the device.

Trimmable microminiature force-sensitive switch

A gas chromatography assembly has a substrate wafer with grooves and a valve seat etched therein. A plate cooperates with the wafer and the grooves to define gas channels: a carrier gas channel and a sample gas channel, each passing through the valve seat. A valve actuator is attached to the valve seat for controlling the flow of sample gas from the sample gas channel into the carrier gas channel. A pump is attached to the wafer and is connected to the sample gas channel. The pump cooperates with the valve actuator to inject sample gas from the sample gas channel into the carrier gas channel. A modular capillary tube and a detector are connected to the carrier gas channel to analyze the properties of the sample gas flowing in the carrier gas channel from the sample gas channel.

Miniature gas chromatograph apparatus

There is described a gas chromatographic assembly formed on a semiconductor wafer by etching techniques. There is also described an improved thermal detector for use therewith.

Growing community of inventors

Palo Alto, CA, United States of America

Stephen C Terry