Abstract: A process transmitter for measuring a process pressure includes a pressure sensor in a sensor housing. An isolation diaphragm which isolates fill fluid from process fluid is spaced apart from a process fluid seal. The spacing reduces deformation of the isolation diaphragm due to a mounting force.

Abstract: A leadless sensor of the type employing a p+ rim which surrounds contact areas, each contact area defined by a metallized portion surrounded by a p+ semiconductor material, which p+ semiconductor materials or fingers are coupled to an active sensor array. The leadless sensor is bonded to a first glass cover member having two slotted apertures which communicate with the active regions of the sensor area on the underside and a top glass contact member which has two slotted regions which communicate with the piezoresistive sensors on the top side of the semiconductor wafer. The glass contact member has a series of corner through holes which are congruent with the contact terminals associated with the semiconductor sensor and which through holes are filled with a glass metal frit to enable contact to be made to the contact terminals of the semiconductor sensor.

Abstract: An oil filled pressure transducer of the type employing a metal diaphragm has a diaphragm of a greater thickness than a conventional diaphragm. The thick diaphragm exhibits and accommodates extremely large pressures and deflects to cause a lower pressure to be transmitted to the oil. Because of the large thickness of the metal diaphragm, the diaphragm dissipates a predetermined percentage of the applied pressure, whereas a corresponding fraction of the applied pressure is transmitted to the oil and hence to the silicon sensors. In this manner the diaphragm acts as a step-down transformer where a portion of the force or pressure applied to the diaphragm is transmitted to the pressure sensor. The pressure sensor receives a pressure which is a fraction of the applied pressure and the sensor is compensated to produce an output proportional to the actual pressure as applied to the thick diaphragm.

Abstract: A transducer packaging assembly for use in a sensing unit subjected to high forces of acceleration includes a base having a cavity. A pressure sensitive semiconductor die is bonded to a large backplate having a shape so that it nestles into the cavity but is spaced from a surface of the cavity. A planar cover secured to the base has a hole larger than the die but smaller than the backplate, and thin wires extend from the die to electrical connections on the assembly. A viscous fluid fills a space between the backplate and the cavity, and a space between the backplate and the cover, and transmits a pressure to be measured to the pressure sensitive die. The viscous fluid has a sufficiently high viscosity to oppose movement of the backplate relative to the cavity while cushioning the pressure sensitive die and the backplate from forces of acceleration.

Abstract: Resistors for use in electrical circuits are formed of an alloy comprising from about 50 to about 95 mol percent aluminum, from about 5 to about 50 mol percent titanium and up to about 15 mol percent of at least one additional metal or a combination of two or more additional metals.

Abstract: An oil filled pressure transducer of the type employing a metal diaphragm has a diaphragm of a greater thickness than a conventional diaphragm. The thick diaphragm exhibits and accommodates extremely large pressures and deflects to cause a lower pressure to be transmitted to the oil. Because of the large thickness of the metal diaphragm, the diaphragm dissipates a predetermined percentage of the applied pressure, whereas a corresponding fraction of the applied pressure is transmitted to the oil and hence to the silicon sensors. In this manner the diaphragm acts as a step-down transformer where a portion of the force or pressure applied to the diaphragm is transmitted to the pressure sensor. The pressure sensor receives a pressure which is a fraction of the applied pressure and the sensor is compensated to produce an output proportional to the actual pressure as applied to the thick diaphragm.

Abstract: A semiconductor component is fashioned of a chip carrier comprising an approximately planar chip carrier surface on which chip carrier surface a semiconductor chip with a pressure sensor is secured, and composed of electrode terminals penetrating the chip carrier and electrically connected to the semiconductor chip, with a surface-mounted arrangement. The chip overlapping the chip carrier.

Abstract: A protective construction for a piezo-resistive silicon pressure transducer intended for connection to a pressure source that exhibits pressure transients. The construction includes the transducer, a conduit for providing pressure communication between the pressure source and the transducer and a flow restrictive device positioned within the conduit.

Abstract: The invention relates to a method of producing a pressure sensor component with a chip carrier which has a substantially planar chip carrier surface and a semiconductor chip with an integrated pressure sensor on the chip carrier surface.

Abstract: A method for sealing a transducer of a type having a diaphragm with an active region and an inactive region, a stress sensing network associated with the active region of the diaphragm, contacts associated with the inactive region of the diaphragm, and lead-outs for coupling the stress sensing network to the contacts. The method comprises oxidizing the transducer to provide a first oxide layer which covers the diaphragm, the stress sensing network, the lead-outs and the contacts. Next, a layer of semiconductive material is deposited over the first oxide layer and is then planarized to provide a planar surface having a substantially flat and bondable surface. Finally, a cover member is bonded to the planar surface of the layer which covers the inactive region of the diaphragm to hermetically seal the stress sensing network and thereby provide a sealed transducer.

Abstract: A sensor device (20) comprises a sensor package (22) having a cavity (24) formed therein, a sensor die (26) mounted on a bottom surface (28) of the cavity (24) and a protective coating (30) formed over the sensor die in the cavity. The protective coating (30) is formed from a material, preferably a polymer material, which is arranged to have a graduated cross-linking density such that the material at the top of the cavity (24) has a high density of cross-linking and the material at the bottom of the cavity (24), which material is in contact with the sensor die, has a low density of cross-linking.

Abstract: A semiconductor composite sensor using a plurality of semiconductor piezoresistive gauge elements connected in series. The piezoresistive elements are separated so that a high potential terminal of one of the resistive elements having the same resistance values and the substrate of the other of the resistive elements will be connected with equal potential values. Potential difference values between semiconductor regions serving as respective resistive elements and the substrates are made equal.

Abstract: The pressure sensor component has a chip carrier with an approximately planar chip carrier surface. A semiconductor chip with an integrated pressure sensor is placed on the chip carrier surface. A pressure-detecting surface area of the pressure sensor is exposed to a pressure to be measured. The component is encapsulated with electrically insulating material that encloses the semiconductor chip and/or the chip carrier at least in regions. A chimney-shaped connection piece that projects up relative to the pressure-detecting area of the pressure sensor penetrates through the encapsulation and is connected to the pressure sensor. The connection piece, which is a separate structural element is incorporated in the component encapsulation and it encloses at least the pressure-detecting surface area in a pressure-tight manner with its end bearing on the semiconductor chip. The connection piece is open toward the outside at its opposite end so as to expose the pressure sensor to the pressure to be measured.

Abstract: A circuit arrangement implemented as an integrated semiconductor component has a measured value acquisition circuit that can be connected to an analysis circuit, in particular a piezoresistive measuring bridge containing piezoresistive measuring shunts diffused on a semiconductor substrate. The piezoresistive measuring shunts are connected to metallic terminal contacts by diffused terminal resistors having a negligible piezoresistive resistance. To avoid terminal-related offset errors on the measuring shunts in particular, the terminal resistors are designed as identical, elongated, generally curved area structures that taper toward the front end and are connected to a measuring shunt on the front end and to a metallic terminal contact on the opposite end.

Abstract: The object of the present invention is to obtain high-precision semiconductor pressure detecting devices without unevenness in gauge resistance values. When a recrystal silicone film 23 is formed by use of laser, a crystal subgrain boundary 27 generates, and crystal fault is included in (100) direction. A metallic wiring 51 of aluminum or gold is arranged on said crystal subgrain boundary 27 crossing a gauge resistance 3A. The current running through a gauge resistance formed by said recrystal silicone film 23 runs into said metallic wiring 51 at the portion of said crystal subgrain boundary 27. Therefore, the current running through said gauge resistance is unlikely to be affected by crystal fault. High-precision and high-sensitivity semiconductor pressure detecting devices are realized with reduced affection by crystal fault.

Abstract: A semiconductor component (31) and a method for coupling a semiconductor device (36) to a substrate (81). The semiconductor component (31) includes a saddle (34) and the semiconductor device (36). The saddle (34) has a plurality of sides (51, 52, 53, 54, 55) that form a semiconductor device receiving area (58). The semiconductor device (36) is inserted into the semiconductor device receiving area (58) and secured in the semiconductor device receiving area (58) using tabs (66, 67). The saddle (34) is coupled to the substrate (81) by fasteners (82,83).

Abstract: A piezoresistive pressure sensor (30) has four resistive diffused regions (32) coupled into a bridge configuration (33) with four junctions (36) and four inside corners (40). Each of the diffused regions has a first end connected to one of the four junctions and a second end connected to a different one of the four junctions. There are four contact diffusion terminals (34) disposed in contact with the bridge configuration, and each of the diffusion terminals is disposed at one of the four junctions such that the diffused regions are electrically connected essentially only by the contact diffusion terminals and an overlap (44, 46) is provided between each of the diffusion terminals and the inside corners to accommodate mask misalignment during manufacture. Thus, no tap is required to electrically connect the contact diffusion terminals to the resistive diffused regions of the bridge, which results in increased sensor sensitivity.

Abstract: An electronic component includes a substrate (201) with a surface (202), a resistor structure (210) supported by the substrate, and a passivation layer (300, 805) over the resistor and the surface of the substrate where the passivation layer has a hole (311, 312, 611, 612, 613, 614, 711, 811), where the surface of the substrate has a compressive portion and a tensile portion, and where the resistor is located between the compressive and tensile portions of the surface.

Abstract: The invention relates to an electronic component manufactured in thick film technology, thin film technology or silicon technology and then provided with an electrically insulating layer which is covered by an amorphous metal layer. The amorphous metal layer protects the component, even with the smallest of layer thicknesses, from external influences and directly transmits heating and force effects.

Abstract: A pressure transducer that includes at least two sensors having substantially similar or substantially identical error characteristics, wherein each sensor is arranged to be subjected to an applied pressure and the outputs of the sensors are electrically coupled so that errors associated with one sensor are compensated by errors associated with the other sensor. The sensors may be substantially identical silicon sensors formed in close proximity on the same wafer.

Abstract: A motion transducer having a user moveable plunger which compresses a spring for generating a force proportional to plunger displacement and applying the generated force to an actuator telescoped onto the plunger. The actuator has an elastomeric pad on the surface which contacts and reacts the generated force onto a force/pressure sensitive resistive strip which varies its resistance with the changing force applied by the elastomeric pad. The changes in resistance may be electrically detected to give an indication of plunger travel.

Abstract: The present invention is a semiconductor pressure sensor. In one embodiment, the semiconductor pressure sensor includes a diaphragm having a first thickness and at least cone raised boss that is coupled to a first side of the diaphragm. The at least one raised boss increases the diaphragm thickness in the region occupied by the at least one raised boss to a second thickness. A plurality of piezoresistors are disposed on a second side of the diaphragm in regions of the first thickness. In another embodiment, a semiconductor pressure sensor diaphragm includes at least one raised boss disposed along a central axis on a first side of the diaphragm. At least two raised bridge regions are disposed along the central axis, interconnecting the at least one raised boss and a diaphragm edge. Each raised bridge region is narrower than the raised boss. A plurality of piezoresistors are disposed on the raised bridge regions of the diaphragm along the central axis.

Abstract: A pressure transducer employing a metal isolation diaphragm. A volume of oil is located between the metal diaphragm and a silicon sensor received in a base member. In order to reduce errors at very low pressure caused by the oil exerting a tension on the deflecting portion of said silicon sensor, the metal diaphragm has an extending dome or dimple above the location of the silicon sensor. The silicon sensor is also recessed below the supporting base plate so that the separation between the silicon sensor and the metal diaphragm increases. The base plate also contains a series of shallow, narrow concentric grooves which further reduces surface tension between the metal diaphragm and the base plate.

Abstract: A semiconductor sensor device including a semiconductor diaphragm member having a top surface coated with an oxide layer; P+ sensor elements fusion bonded to the oxide layer at a relatively central area of the diaphragm; P+ finger elements fusion bonded to the oxide layer extending from the sensors to an outer contact location of the diaphragm for each finger; and an external rim of P+ material fusion bonded to the oxide layer and surrounding the sensors and fingers. A first glass wafer member is electrostatically bonded at a bottom surface to the fingers and rim to hermetically seal the sensors and fingers of the diaphragm member. The first glass wafer includes a depression above the sensors and has a plurality of apertures, where each aperture is associated with a separate finger at the contact location and each aperture being smaller than the associated finger lining up with the contact location wherein each contact location can be accessed via the associated aperture in the first glass wafer member.

Abstract: A single-sided differential pressure sensing chip having a cavity formed in the top surface of a substrate, a deformable diaphragm spanning the cavity, and a pressure passage connecting the top surface of the substrate with the cavity, and a method of making the same are described. A first fluid pressure applied to the top surface of the substrate in the vicinity of the diaphragm exerts a force on the top surface of the diaphragm, and a second fluid pressure applied to the top surface of the substrate near the pressure passage exerts a force on the bottom surface of the diaphragm. The diaphragm deflects in response to the forces exerted upon it, and a sensing element detects the flexing of the diaphragm. The pressure sensing chip can be contained within a housing structure formed of a carrier and a cap.

Abstract: A thick-film strain-sensing structure for a media-compatible, high-pressure sensor. The strain-sensing structure generally includes a metal diaphragm, at least one electrical-insulating layer on the diaphragm, an interface layer on the electrical-insulating layer, and at least one thick-film piezoresistor on the interface layer for sensing deflection of the diaphragm. The interface layer and the electrical-insulating layers are preferably formed by thick-film processing, as done for the piezoresistors. For compatibility with the metal diaphragm, the electrical-insulating layer has a CTE near that of the diaphragm. The interface layer is formulated to inhibit and control diffusion of the electrical-insulating layers into the piezoresistors. For this purpose, the interface layer is formed from a composition that contains, in addition to a suitable organic media, alumina, zinc oxide, and at least one glass frit mixture comprising lead oxide, a source of boron oxide such as boric acid, silica and alumina.

Abstract: A reduced size, hermetically sealed semiconductor transducer and methods for fabricating the same. In a preferred embodiment, the transducer comprises a transducer wafer including a diaphragm which deflects upon the application of a force thereto. At least one semiconductor transducer element and one electrical contact are disposed on a top surface of the transducer wafer, with the electrical contact coupled to the semiconductor element and extending to a peripheral portion of the wafer. A cover member is provided that is dimensioned to surround the semiconductor element. A peripheral glass frit bond is formed between the cover member and the transducer wafer, and between the cover member and at least a portion of the electrical contact. An aperture is formed in a top portion of the cover member, positioned above a region bounded by the peripheral glass bond. This aperture functions to prevent air gap formation in the peripheral glass frit bond.

Abstract: A method of compensating for differences of temperature, in a pressure sensor of the kind wherein a pressure is sensed by use of a diaphragm connected in a Wheatstone bridge circuit. First measurement points of offset output signals emanating from the bridge in the pressure sensor at a number of temperature levels are plotted in a first graph indicating the voltage as a function of the resulting resistance of the bridge, whereupon adjacent measurement points are interconnected by straight lines and calculation is effected through interpolation between the measurement points. The sensitivity of the pressure sensor such as voltage/pressure unit, is determined in a corresponding manner at different temperature levels by plotting second measurement points in a second graph indicating the sensitivity as a function of the resulting resistance in a similar way the last mentioned measurement points are interconnected by straight lines, and calculation is effected through interpolation between the measurement points.

Abstract: A combustion pressure sensor suitable for a highly precise combustion control system of an automobile engine and a sensing system using the sensor. The combustion pressure sensor includes a SOI substrate having a three-layered structure of a first silicon plate, a thermal oxide film, and a second silicon plate, wherein a combustion pressure is sensed on the basis of a pressure or a force applied to the first silicon plate.

Abstract: A media-compatible, high-pressure transducer cell (12), a rugged sensor assembly (10) incorporating the cell (12), and a method for its production. The pressure cell (12) generally includes a metal body having a diaphragm (26), at least one dielectric layer (28, 38) on the diaphragm (26), and at least one thick-film piezoresistive element (34) on the dielectric layer (28, 38) for sensing deflection of the diaphragm (26). For purposes of compatibility with a wide variety of media, the metal body is preferably formed of steel, most preferably a stainless steel alloy such as an AISI Type 300 or 400 Series. The diaphragm (26) can be formed by etching or machining the metal body. The dielectric layers (28, 38) are preferably formed by thick-film processing as done for the piezoresistive element (34), employing materials that will adhere to the metal diaphragm (26), withstand the strains induced as the diaphragm (26) deflects, and faithfully transmit such strains to the thick-film piezoresistor (34).

Abstract: The semiconductor pressure sensor has a pressure sensor unit with a pressure sensor chip for detecting pressure, peripheral circuitry for converting the pressure detected by the pressure sensor unit to an electrical signal and processing the electrical signal, a lead frame for fastening and electrically connecting peripheral circuitry, a package in which the peripheral circuitry and lead frame are integrated in a resin molding including a cavity in which the pressure sensor unit is housed, a cover for closing the opening of the cavity in which the pressure sensor unit is housed, and a pressure opening for conveying a pressure-conveying medium to the pressure sensor chip. The pressure sensor unit is fastened to the inside bottom of the cavity and is electrically connected to a particular part of the lead frame exposed inside the cavity.

Abstract: An improved resistor and connection region structure in which the geometries of the connection regions for a pair of radial resistors correspond to the connection region geometries for a pair of tangential resistors, thus inherently eliminating the need for varying connection regions to compensate for offset. In particular, the radial resistors are formed by placing two legs in parallel with each other and connecting those legs in series on opposite sides of the membrane, with the connection region on the interior of the membrane. The tangential resistors, on the other hand, are formed on the opposite sides by placing two legs in series with each other and connecting those legs in series, with an interior connection region connecting them.

Abstract: A pressure sensor is provided with a compressible insert that is disposed within an internal opening of a potentially frangible component, such as a tubular glass member. If a condensate forms within the internal opening of the tubular glass member, freezing of the condensate can cause it to expand and damage the glass member. The compressible insert absorbs the expansion of the liquid condensate by compressing and prevents the expanding condensate from cracking the tubular glass member. The compressible insert, in a particularly preferred embodiment of this invention, has an opening extending therethrough to facilitate the transmission of pressure throughout the aligned openings of the pressure sensor. In one particular embodiment, a silicone die is etched to provide a cavity and corresponding diaphragm portion on which piezoresistive elements are disposed.

Abstract: Disclosed is the method of producing a piezo-device utilizing an ultra-thin Mo-C film as a piezoresistive material for a general class of improved piezo-device with the high sensitivity and the weak temperature dependence.

Abstract: A pressure sensor comprising a hollow main body (1) defining a bore (3) extending therethrough. A pressure sensing assembly (12) is disposed within the bore (3) to divide it into a detection cavity (3a) for transmitting therethrough the pressure to be detected at a pressure receiving end (3c) thereof and an output cavity (3b) through which an output signal from the pressure sensing assembly (12) is to be supplied. A flexible metal diaphragm (40) is attached to the main body (1) at the pressure receiving end (3c) to seal the detection cavity (3a) in which a pressure transmitting medium (11) is filled. The flexible metal diaphragm ( 40) has a resonance frequency above an oscillation frequency range of the pressure to be detected. Preferably, the effective diameter of the diaphragm (40) may be from 7.5 mm to 8.5 mm and the thickness dimension thereof may be from 35 .mu.m to 45 .mu.m.

Abstract: A form pressure sensor diaphragm and method of making that allows for formation of long rectangular plate structures in semiconducting materials, especially silicon. A plurality or multiplicity of sensors may be constructed on a single chip, thus providing for absolute and relative sensing of pressure on a single device.

Abstract: A polycrystalline pressure sensor is formed by depositing polycrystalline silicon piezoresistors on a polycrystalline sensing diaphragm. The piezoresistors are arranged in a wheatstone bridge configuration. During operation, an alternating differential signal is applied across the input of the wheatstone bridge. A measured voltage difference between the output terminals of the wheatstone bridge is used to detect imbalance in the electrical piezoresistors that corresponds to pressure applied to the sensor. Pressure is thereby measured.

Abstract: A pressure sensor die is provided with a flexible membrane and a plunger which combine to amplify a low pressure signal while also providing media isolation between a fluid being measured and the internal components of a pressure sensor. One embodiment of the pressure sensor disposes an end of the plunger in direct contact with a pressure sensor die while another embodiment disposes an elastomeric diaphragm between the plunger and the pressure sensor die. This second embodiment creates a chamber between the plunger and the pressure sensor die in which a fluid is captured by movement of the plunger. The captured fluid is decreased in volume by movement of the plunger and the resulting increase in pressure in transmitted to a pressure sensitive portion of a pressure sensor die. The device is particularly useful in conjunction with applications where media isolation is required between the fluid being measured and the components of the pressure sensor, such as kidney dialysis machines.

Abstract: The micromachine includes a movable portion, an unmovable portion surrounding the movable portion, a connecting portion for connecting the movable portion with the unmovable portion in a cantilever fashion, and a support member for connecting the movable portion with the unmovable portion at a location other than a location at which the movable portion is connected with the unmovable portion through the connecting portion. The support member is formed of weaker material than material of which all of the portions are formed, with respect to any one of properties which all of the portions have. Thus, only the support member can be cut off by applying energy effective to the one of properties thereto after the micromachine has been packaged.

Abstract: A method of fabricating a high pressure piezoresistive pressure transducer having a substantially linear pressure versus stress output over its full range of operation. The method involves bonding a carrier wafer having a dielectric isolating layer on one surface and a supporting member on the opposite surface, to a pattern wafer containing at least two single crystalline longitudinal piezoresistive sensing elements of a second conductivity. Both the pattern wafer and sections of the carrier wafer are etched leaving the piezoresistive sensing elements bonded directly to the dielectric isolating layer, and a diaphragm member having a deflecting portion and a non-deflecting portion. The diaphragm member is constructed to have an aspect ratio which is of the order of magnitude of one.

Abstract: A semiconductor pressure sensor utilizes single-crystal silicon piezoresistive gage elements dielectrically isolated by silicon oxide from other such elements, and utilizes an etched silicon substrate. P-type implants form p-type piezoresistive gage elements and form p+ interconnections to connect the sensor to external electrical devices. The diaphragm is made from polysilicon and is deposited on top of the gage elements.

Abstract: A pressure sensor comprises a pressure-sensitive coupler body 2 having one end provided with a diaphragm 8 and strain gage 9 stacked together, an intermediate body 3 containing a printed board 21 and encircling the strain gate 9, and a signal-detective coupler body 4 opposed to the pressure-sensitive coupler body 2 via the intermediate body 3 to define a closed chamber in the intermediate body 3. The printed board 21 and the strain gage 9 are electrically connected by terminal elements 13 extended from the strain gage 9 into slidable contact with conductive elements 25 attached to an edge of the printed board 21. Vibrations or impulses produced in the diaphragm 8 are therefore absorbed by a relative displacement between the terminal elements 13 and the conductive elements 25 to protect the printed board 21 against such vibrations or impulses.

Abstract: A high pressure sensor structure (11, 111, 211) includes a housing (12, 112, 212) having an upper cavity portion (13, 113, 213) and a lower cavity portion (16, 116, 216). A diaphragm (18, 118, 218) separates the upper cavity portion (13, 113, 213) from the lower cavity portion (16, 116, 216). A semiconductor chip (26, 126, 226) is attached to the upper surface of the diaphragm (18, 118, 218) within the upper cavity portion (13, 113, 213). The diaphragm (18, 118, 218) has a thickness (21, 121, 221) and an exposed width (23, 123, 223) such that the semiconductor chip (26, 126, 226) generates a measurable output signal when the lower surface of the diaphragm (18, 118, 218) is exposed to a high pressure environment.

Abstract: A sensor for detecting physical amount in which a gauge resistance value is made not to change even when a wiring material presents a yield phenomenon by wiring a wiring material Such as aluminum presenting a yield phenomenon by thermal stress in a stress insensitive direction of a piezogauge.

Abstract: A differential pressure transmitter having a differential pressure sensor, a temperature sensor and a static pressure sensor all provided on the semiconductor substrate of a single semiconductor chip. A reference resistor is provided in a part of the chip. Resistances of the differential pressure sensor and the reference resistor are compared periodically in order to determine the condition including service life of the differential pressure sensor.

Abstract: A pressure-adjusting device for adjusting an output of an integrated pressure sensor in which a silicon wafer is joined onto a seat that has pressure-adjusting passages formed therein, and which has formed in the silicon wafer a signal processing circuit with an adjusting resistor for each chip, a thin diaphragm for each chip and a piezo-resistance layer for each chip. The pressure-adjusting device includes a pressure-setting stage on which the seat is placed, the pressure setting stage having pressure-adjusting passages formed therein to adjust a pressure exerted on the respective thin diaphragm via the pressure-adjusting passages formed in the seat. A holding member is arranged on the pressure-setting stage as to surround at least an outer periphery of the seat. A first elastic air-tight member is arranged on the pressure-setting stage as to surround the outer periphery of the seat and be held compressed by the pressure-setting stage and by the holding member.

Abstract: A form of pressure sensor diaphragm and method of making that allows for the formation of long rectangular plate structures in semiconducting material, especially Silicon. A plurality or multiplicity of sensors may be constructed on a single chip, thus providing for absolute and relative sensing of pressure on a single device.

Abstract: A semiconductor strain sensor includes a silicon substrate, a strain resistive element and electrodes. The silicon substrate has a deformable portion which is deformed when stress is applied to it. The strain resistive element is formed on the deformable portion and has an at least a first layer and a second layer which form a heterojunction between them. The first layer is doped with impurities so that a two-dimensional carrier gas layer is formed in the second layer near the heterojunction. The two-dimensional carrier gas layer has carriers originating from the impurities. The electrodes electrically contact the two dimensional carrier gas layer. Change of resistance of the strain resistive element in accordance with the stress is detected through the electrodes.

Abstract: A resistive strain gauge sensor of the type including a circuit board carrying circuitry, a diaphragm bonded to the circuit board, and strain gauge circuitry on the diaphragm. The strain gauge circuitry includes a plurality of leads defining free ends and the circuitry on the circuit board defines a plurality of leads defining free ends. The diaphragm is bonded to the circuit board by a frit layer and the frit layer includes voids which are in respective alignment with the free ends of the strain gauge leads and the free ends of the circuit board leads. A conductive epoxy is positioned in the voids in the frit layer to establish electrical communication between the strain gauge circuitry leads and the circuit board leads without the use of solder joints.

Abstract: A pressure-measuring head for measuring the pressure of a fluid consists of a membrane-like diaphragm (6), which separates a pressure chamber (4) from a reference chamber (7), to which the pressure-sensitive elements, e.g., thick-film resistors or strain gauges, are applied. Under the effect of the pressure in the pressure chamber, these pressure-sensitive elements perform a deflection which is proportional to the pressure occurring in the pressure chamber. An electric contact is switched during simultaneous displacement of the membrane (6) arranged in a sensor housing by a predeterminable distance (19) after a defined pressure value has been reached in the pressure chamber. A measuring head of such a design is also able to assume a swithing function without additional auxiliary energy, besides sending an electrically processable pressure signal.