A method of manufacturing an overheat or fire alarm detection system, comprises the steps of micromachining a pressure sensor and securing a sensor tube in fluid communication with the pressure sensor. The sensor tube may comprise a hollow tube containing a material that evolves gas upon heating. The micromachining step may comprise doping at least a portion of a first layer, forming a cavity at least partially within the doped portion and forming a deformable diaphragm over the cavity.

According to some aspects of the subject technology, an apparatus includes a first electrode, a second electrode and a dielectric membrane disposed between the first electrode and the second electrode. The first electrode and the second electrode include a number of pores within a region of an input port of the apparatus. The first electrode, the second electrode and the dielectric membrane form a capacitor that is configured to enable detection of occlusion of the input port by water.

An electromechanical device includes a stack formed of an insulating layer interposed between two solid layers, and a micromechanical structure of predetermined thickness suspended above a recess of predetermined depth, the recess and the micromechanical structure forming one of the two solid layers of the stack, and the insulating layer forming the bottom of the recess.

A manufacturing method of a semiconductor device, in which a vacuum-pressure airtight chamber is defined by a space between a first substrate and a recessed portion of a second substrate, includes preparing the first substrate and the second substrate both of which contain silicon, joining the two substrates together, performing a heat treatment to emit hydrogen gas from the airtight chamber, and generating OH groups on the substrates before the joining. In the joining of the substrates together, the OH groups are bonded together to generate covalent bonds, and in the heat treatment, a part on which the OH groups are generated is heated at a temperature rise rate of 1° C./sec or smaller until a temperature of the substrate increases to 700° C. or higher, and a heating temperature and heating time are adjusted to emit hydrogen gas from the airtight chamber.

A differential pressure sensor may include a body with a first end, second end and wall wherein the first and second ends comprise isolator diaphragms connected to first and second process fluid inlets. A MEMS pressure sensor including a pressure sensing diaphragm with first and second sides may be mounted on a hollow pedestal adhesively attached to an annular bottom of a cylindrical cavity wherein the first side of the sensor is coupled to the first isolator diaphragm by a first fill fluid and the second side of the sensor is coupled to the second isolator diaphragm through the interior of the hollow pedestal by a second fill fluid volume wherein the first and second fill fluid volumes are separated by an adhesive seal between the bottom of the cylindrical cavity and the bottom of the hollow pedestal wherein the cylindrical cavity comprises a first cylindrical wall with a first diameter in contact with the annular bottom, a frustroconical portion in contact with the first cylindrical wall and in contact with a second cylindrical wall with a second diameter larger than the first diameter such that the increased distance between the pedestal and the cylindrical wall prevents adhesive moving up the space between the pedestal and cavity wall from the bottom of the cavity when the pressure sensor and hollow pedestal are mounted in the cavity. The sensor further includes sensor elements on the MEMS diaphragm that provide an indication of pressure differences between the first and second process fluids.

A semiconductor structure is provided. The semiconductor structure includes a substrate, a plurality of vias, a signal transmitting portion, a heater and a sensing material. The plurality of vias penetrates the substrate, wherein each of the plurality of vias includes a conductive or semiconductive portion surrounded by an oxide layer. The signal transmitting portion is disposed in the substrate, wherein adjacent vias of the plurality of vias surrounds the signal transmitting portion. The heater is electrically connected to the signal transmitting portion, and the sensing material is disposed over the heater and electrically connected to the substrate. A method of manufacturing a semiconductor structure is also provided.

This invention describes the structure and function of an integrated multi-sensing system. Integrated systems described herein may be configured to form a microphone, pressure sensor, gas sensor, multi-axis gyroscope or accelerometer. The sensor uses a variety of different Field Effect Transistor technologies (horizontal, vertical, Si nanowire, CNT, SiC and III-V semiconductors) in conjunction with MEMS based structures such as cantilevers, membranes and proof masses integrated into silicon substrates. It also describes a configurable method for tuning the integrated system to specific resonance frequency using electronic design.

According to one embodiment, a strain and pressure sensing device includes a semiconductor circuit unit and a sensing unit. The semiconductor circuit unit includes a semiconductor substrate and a transistor. The transistor is provided on a semiconductor substrate. The sensing unit is provided on the semiconductor circuit unit, and has space and non-space portions. The non-space portion is juxtaposed with the space portion. The sensing unit further includes a movable beam, a strain sensing element unit, and first and second buried interconnects. The movable beam has fixed and movable portions, and includes first and second interconnect layers. The fixed portion is fixed to the non-space portion. The movable portion is separated from the transistor and extends from the fixed portion into the space portion. The strain sensing element unit is fixed to the movable portion. The first and second buried interconnects are provided in the non-space portion.

A device comprises a silicon-on-insulator (SOI) substrate having first and second silicon layers with an insulator layer interposed between them. A structural layer, having a first conductivity type, is formed on the first silicon layer. A well region, having a second conductivity type opposite from the first conductivity type, is formed in the structural layer, and resistors are diffused in the well region. A metallization structure is formed over the well region and the resistors. A first cavity extends through the metallization structure overlying the well region and a second cavity extends through the second silicon layer, with the second cavity stopping at one of the first silicon layer and the insulator layer. The well region interposed between the first and second cavities defines a diaphragm of a pressure sensor. An integrated circuit and the pressure sensor can be fabricated concurrently on the SOI substrate using a CMOS fabrication process.

Pressure sensors having ring-tensioned membranes are disclosed. A tensioning ring is bonded to a membrane in a manner that results in the tensioning ring applying a tensile force to the membrane, flattening the membrane and reducing or eliminating defects that may have occurred during production. The membrane is bonded to the sensor housing at a point outside the tensioning ring, preventing the process of bonding the membrane to the housing from introducing defects into the tensioned portion of the membrane. A dielectric may be introduced into the gap between the membrane and the counter electrode in a capacitive pressure sensor, resulting in an improved dynamic range.