Abstract: Embodiments of embedded MEMS sensors and related methods are described herein. Other embodiments and related methods are also disclosed herein.

Abstract: A capacitive pressure sensor includes a semiconductor substrate, a first insulating portion configured to define a sensor region, a reference pressure chamber configured to divide a lower portion of the sensor region in a direction, a second insulating portion configured to divide a surface portion of the sensor region above the reference pressure chamber in the direction, and a trench configured to divide the sensor region in the direction. The sensor region is divided into at least three semiconductor parts by the reference pressure chamber, the second insulating portion, and the trench.

Abstract: Disclosed is an integrated circuit (100), comprising a semiconductor substrate (110) carrying a plurality of circuit elements; and a pressure sensor including a cavity (140) on said semiconductor substrate, said cavity comprising a pair of electrodes (120, 122) laterally separated from each other; and a flexible membrane (130) over and spatially separated from said electrodes such that said membrane interferes with a fringe field between said electrodes, said membrane comprising at least one aperture (132). A method of manufacturing such an IC is also disclosed.

Abstract: A capacitance type pressure sensor includes a semiconductor substrate having a reference pressure compartment formed therein, a diaphragm formed of a portion of the semiconductor substrate and formed in a surface layer portion of the semiconductor substrate to define the reference pressure compartment, the diaphragm having a through-hole communicating with the reference pressure compartment, fillers arranged within the through-hole, and an isolation insulating layer surrounding the diaphragm to isolate the diaphragm from the remaining portion of the semiconductor substrate.

Abstract: A condenser microphone having a flexure hinge diaphragm and a method of manufacturing the same are provided. The method includes the steps of: forming a lower silicon layer and a first insulating layer; forming an upper silicon layer on the first insulating layer; forming sound holes by patterning the upper silicon layer; forming a second insulating layer and a conductive layer on the upper silicon layer; forming a passivation layer on the conductive layer; forming a sacrificial layer on the passivation layer; depositing a diaphragm on the sacrificial layer, and forming air holes passing through the diaphragm; forming electrode pads on the passivation layer and a region of the diaphragm; and etching the layers to form an air gap between the diaphragm and the upper silicon layer. Consequently, a manufacturing process may improve the sensitivity and reduce the size of the condenser microphone.

Abstract: A sensor module and semiconductor chip. One embodiment provides a carrier. A semiconductor chip includes a first recess and a second recess and a main surface of the semiconductor chip. The semiconductor chip is mounted to the carrier such that the first recess forms a first cavity with the carrier and the second recess forms a second cavity with the carrier. The first cavity is in fluid connection with the second cavity.

Abstract: The present invention discloses a Micro-Electro-Mechanical System (MEMS) pressure sensor device and a manufacturing method thereof. The MEMS pressure sensor device includes: a substrate having at least one recess formed on an upper surface thereof, the recess defining a boss; a membrane, which is bonded to at least a part of the upper surface and at least a part of the boss, so that the at least one recess forms a cavity; at least one sensing unit, which is coupled to the membrane, for sensing deflection of the membrane; and an opening, which is formed on a lower surface of the substrate, and connects to the cavity.

Abstract: A fabricating method of integrated circuit is provided. During the fabricating process of an interconnecting structure of the integrated circuit, a micro electromechanical system (MENS) diaphragm is formed between two adjacent dielectric layers of the interconnecting structure. The method of forming the MENS diaphragm includes the following steps. Firstly, a plurality of first openings is formed within any dielectric layer to expose corresponding conductive materials of the interconnecting structure. Secondly, a bottom insulating layer is formed on the dielectric layer and filling into the first openings. Third, portions of the bottom insulating layer located in the first openings are removed to form at least a first trench for exposing the corresponding conductive materials. Then, a first electrode layer and a top insulating layer are sequentially formed on the bottom insulating layer, and the first electrode layer filled into the first trench and is electrically connected to the conductive materials.

Abstract: Provided is a method of manufacturing a capacitive electromechanical transducer using fusion bonding, which is capable of reducing fluctuations in initial deformation among diaphragms caused at positions having different boundary conditions such as the bonding area, thereby enhancing the uniformity of the transducer and stabilizing the sensitivity and the like. The method of manufacturing a capacitive electromechanical transducer includes: forming an insulating layer on a first silicon substrate and forming at least one recess; fusion bonding a second silicon substrate onto the insulating layer; and thinning the second silicon substrate and forming a silicon film. The method further includes, before the bonding of the second silicon substrate onto the insulating layer, forming a groove in the insulating layer at the periphery of the at least one recess.

Abstract: An exemplary method for a producing a piezoelectric vibrating piece having at least one mesa step includes forming a metal film on a main surface of a piezoelectric wafer. A through-groove is formed through the thickness of the wafer to form a plan profile of a desired piezoelectric substrate. A film of photoresist is formed on the surface of the metal film. A resist is applied, exposed, and formed into a resist pattern that defines a first mesa step along at least a portion of the plan profile. In regions not protected by the metal film, the piezoelectric substrate is etched to a defined depth to form a mesa step. The denuded edge surface of the metal film is edge-etched. A second mesa step, inboard of the first mesa step, can be formed by repeating the edge-etching and substrate-etching steps using the metal film as an etch protective film.

Abstract: A sensor and method for fabricating a sensor is disclosed that in one embodiment bonds an etched semiconductor substrate wafer to an etched first device wafer comprising a silicon on insulator wafer which is then bonded to a second device wafer comprising a silicon on insulator wafer to create a vented, suspended structure, the flexure of which is sensed by an embedded sensing element to measure differential pressure. In one embodiment, interconnect channels embedded in the sensor facilitate streamlined packaging of the device while accommodating interconnectivity with other devices.

Abstract: A method for fabricating a sensor is disclosed that in one embodiment bonds an etched semiconductor substrate wafer to an etched device wafer comprising a double silicon on insulator wafer to create a suspended structure, the flexure of which is sensed by an embedded piezoresistive sensor element. In one embodiment the sensor measures acceleration. In other embodiments the sensor measures pressure.

Abstract: A device includes a semiconductor substrate, and a capacitive sensor having a back-plate, wherein the back-plate forms a first capacitor plate of the capacitive sensor. The back-plate is a portion of the semiconductor substrate. A conductive membrane is spaced apart from the semiconductor substrate by an air-gap. A capacitance of the capacitive sensor is configured to change in response to a movement of the polysilicon membrane.

Abstract: In various embodiments, a chip may include a substrate; a coating, the coating covering the substrate at least partially and the coating being designed for being stripped at least partially by means of laser ablation; wherein between the substrate and the coating, a laser detector layer is arranged at least partially, the laser detector layer being designed for generating a detector signal for ending the laser ablation.

Abstract: The device layer of a 6-degrees-of-freedom (6-DOF) inertial measurement system can include a single proof-mass 6-axis inertial sensor formed in an x-y plane, the inertial sensor including a main proof-mass section suspended about a single, central anchor, the main proof-mass section including a radial portion extending outward towards the edge of the inertial sensor, a central suspension system configured to suspend the 6-axis inertial sensor from the single, central anchor, and a drive electrode including a moving portion and a stationary portion, the moving portion coupled to the radial portion, wherein the drive electrode and the central suspension system are configured to oscillate the 6-axis inertial sensor about a z-axis normal to the x-y plane.

Abstract: Embodiments of displays with embedded MEMS sensors and related methods are described herein. Other embodiments and related methods are also disclosed herein.

Abstract: A method of forming a surface passivation layer on a surface of a crystalline silicon substrate is disclosed. In one aspect, the method includes depositing an Al2O3 layer on the surface, the Al2O3 layer having a thickness not exceeding about 15 nm; performing an outgassing process at a temperature in the range between about 500° C. and 900° C., after the deposition of the Al2O3 layer on the surface; and after the outgassing process, depositing at least one additional dielectric layer such as a silicon nitride layer and/or a silicon oxide layer on the Al2O3 layer.

Abstract: A micromechanical component having a conductive substrate, a first conductive layer provided above the substrate and that forms, above a cavity provided in the substrate, an elastically deflectable diaphragm region of monocrystalline silicon and an adjacent peripheral region, a circuit trace level provided above the first conductive layer in a manner that is electrically insulated from the first conductive layer, the circuit trace level having above the diaphragm region a first electrode region and having above the peripheral region a first connection region electrically connected to the same, and a second conductive layer that is provided above the circuit trace level, the second conductive layer having above the diaphragm region a second electrode region that is electrically insulated from the first electrode region, and having above the peripheral region a second connection region electrically insulated from the second electrode region and electrically connected to the first connection region.

Abstract: A micromechanical systems (MEMs) pressure sensor includes a semiconductor substrate having a deep well located within a first surface and a cavity located within a second, opposing surface. The semiconductor substrate has a first doping type. The deep well has a second doping type, with a gradient doping profile, thereby forming a PN junction within the substrate. The cavity forms a diaphragm, which is a substrate section that is thinner than the surrounding substrate sections, that comprises the deep well. One or more pizeoresistor elements are located within the deep well. The piezoresistors are sensitive to deformations, such as bending, in the diaphragm caused by changes in the pressure of the cavity.

Abstract: The present disclosure provides a microstructure device with an enhanced anchor and a narrow air gap. One embodiment of a microstructure device provided herein includes a layered wafer. The layered wafer includes a silicon handle layer, a buried oxide layer formed on the handle layer, and a silicon device layer formed on the buried oxide layer. A top oxide layer is formed on the device layer. The top oxide layer, the device layer, and the buried oxide layer are etched, thereby forming trenches to create an anchor and a microstructure device in the device layer. In process of fabricating the device, a thermal oxide layer is formed along sides of the microstructure device to enclose the microstructure device in the buried oxide layer, the top oxide layer and the thermal oxide layer. Then, a poly layer if formed to fill in the trenches and enclose the anchor. After the poly layer fills in the trenches, the oxide layers enclosing the microstructure device are etched away, releasing the microstructure device.

Abstract: A semiconductor pressure sensor includes a cavity disposed in one silicon substrate of a SOI substrate having two silicon substrates bonded to each other with an oxide film therebetween and a diaphragm formed from the other silicon substrate and the oxide film, wherein the oxide film, bordering the cavity, of the diaphragm includes an arc-shaped section at the boundary portion to the one silicon substrate defining the inner wall side surface of the cavity, the arc-shaped section having the same width as the width of the cavity at a desired section in the one silicon substrate and reducing the width of the cavity from the boundary portion toward the diaphragm center.

Abstract: Method is to fabricate a MEMS device with a substrate. The substrate has through holes in the substrate within a diaphragm region and optionally an indent space from the second surface at the diaphragm region. A first dielectric structural layer is then disposed over the substrate from the first surface, wherein the first dielectric structural layer has a plurality of openings corresponding to the through holes, wherein each of the through holes remains exposed by the first dielectric structural layer. A second dielectric structural layer with a chamber is disposed over the first dielectric structural layer, wherein the chamber exposes the openings of the first dielectric structural layer and the through holes of the substrate to connect to the indent space. A MEMS diaphragm is embedded in the second dielectric structural layer above the chamber, wherein an air gap is formed between the substrate and the MEMS diaphragm.

Abstract: A method of etching a sacrificial layer for a micro-machined structure, the sacrificial layer positioned between a layer of a first material and a layer of a second material, the etching being carried out by an etching agent. The method includes: providing at least one species having an affinity for the etching agent greater than that of the layers of first material and second material and less than or equal to that of the sacrificial layer; and then etching the sacrificial layer by the etching agent, the etching being carried out to eliminate at least partially the sacrificial layer and then to eliminate at least partially the species.

Abstract: A high-frequency capacitive micromachined ultrasonic transducer (CMUT) has a silicon membrane and an overlying metal silicide layer that together form a conductive structure which can vibrate over a cavity. The CMUT also has a metal structure that touches a group of conductive structures. The metal structure has an opening that extends completely through the metal structure to expose the conductive structure.

Abstract: A condenser microphone having a flexure hinge diaphragm and a method of manufacturing the same are provided. The method includes the steps of: forming a lower silicon layer and a first insulating layer; forming an upper silicon layer on the first insulating layer; forming sound holes by patterning the upper silicon layer; forming a second insulating layer and a conductive layer on the upper silicon layer; forming a passivation layer on the conductive layer; forming a sacrificial layer on the passivation layer; depositing a diaphragm on the sacrificial layer, and forming air holes passing through the diaphragm; forming electrode pads on the passivation layer and a region of the diaphragm; and etching the layers to form an air gap between the diaphragm and the upper silicon layer. Consequently, a manufacturing process may improve the sensitivity and reduce the size of the condenser microphone.

Abstract: A method for etching a diaphragm pressure sensor based on a hybrid anisotropic etching process. A substrate with an epitaxial etch stop layer can be etched utilizing an etching process in order to form a diaphragm at a selective portion of the substrate. The diaphragm can be oriented at an angle (e.g., 45 degree) with respect to the substrate in order to avoid an uncertain beveled portion in a stress/strain field of the diaphragm. The diaphragm can be further etched utilizing an etch finishing process to create an anisotropic edge portion on the major areas of the diaphragm and optimize the thickness and size of the diaphragm. Such an approach provides an enhanced diaphragm structure with respect to a wide range of pressure sensor applications.

Abstract: System, devices and methods are presented that integrate stretchable or flexible circuitry, including arrays of active devices for enhanced sensing, diagnostic, and therapeutic capabilities. The invention enables conformal sensing contact with tissues of interest, such as the inner wall of a lumen, a the brain, or the surface of the heart. Such direct, conformal contact increases accuracy of measurement and delivery of therapy. Further, the invention enables the incorporation of both sensing and therapeutic devices on the same substrate allowing for faster treatment of diseased tissue and fewer devices to perform the same procedure.

Abstract: A metal mesh lid MEMS package includes a substrate, a MEMS electronic component coupled to the substrate, and a metal mesh lid coupled to the substrate with a lid adhesive. The metal mesh lid includes a polymeric lid body having a top port formed therein and a metal mesh cap coupled to the lid body. The metal mesh cap covers the top port and serves as both a particulate filter and a continuous conductive shield for EMI/RF interferences. Further, the metal mesh cap provides a locking feature for the lid adhesive to maximize the attach strength of the metal mesh lid to the substrate.

Abstract: A method for producing a component having at least one diaphragm formed in the upper surface of the component, which diaphragm spans a cavity, and having at least one access opening to the cavity from the back side of the component, at least one first diaphragm layer and the cavity being produced in a monolithic semiconductor substrate from the upper surface of the component, and the access opening being produced in a temporally limited etching step from the back side of the substrate. The access opening is placed in a region in which the substrate material comes up to the first diaphragm layer.

Abstract: A method of manufacturing a MOSFET includes the steps of preparing a substrate with an epitaxial growth layer made of silicon carbide, performing ion implantation into the substrate with the epitaxial growth layer, forming a protective film made of silicon dioxide on the substrate with the epitaxial growth layer into which the ion implantation was performed, and heating the substrate with the epitaxial growth layer on which the protective film was formed to a temperature range of 1600° C. or more in an atmosphere containing gas including an oxygen atom.

Abstract: A capacitance type micro-silicon microphone includes a base, a backplate and a diaphragm positioned above the backplate in a suspended manner. The base includes a top face, a bottom face and a number of sound bores recessing inwardly from the top face. Bottom sides of the sound bores are in communication with each other so as to form an upper cavity. The base defines at least one lower cavity recessing inwardly from the bottom face. The backplate is positioned above the upper cavity in a suspended manner. The lower cavity is in communication with the upper cavity so as to jointly form a back cavity of the capacitance type micro-silicon microphone. Besides, a method for fabricating the capacitance type micro-silicon microphone is also disclosed.

Abstract: Provided is a method of manufacturing an electromechanical transducer having a reduced variation in a breakdown strength caused by a variation in flatness of an insulating layer. In the method of manufacturing the electromechanical transducer, a first insulating layer is formed on a first substrate, a barrier wall is formed by removing a part of the first insulating layer, and a second insulating layer is formed on a region of the first substrate after the part of the first insulating layer has been removed. Next, a gap is formed by bonding a second substrate on the barrier wall, and a vibration film that is opposed to the second insulating layer via the gap is formed from the second substrate. In the forming of the barrier wall, a height on a gap side in a direction vertical to the first substrate becomes lower than a height of a center portion.

Abstract: In a method of manufacturing a semiconductor pressure sensor, a multilayer structure including a polysilicon diaphragm, a polysilicon gauge resistor formed on a side of a space which is to serve as a vacuum chamber below the polysilicon diaphragm, and a group of insulating films containing the polysilicon diaphragm and the polysilicon gauge resistor and having an etching solution introduction hole in contact with a sacrificial layer is formed on the sacrificial layer. Then, an etching solution is supplied through the etching solution introduction hole and the sacrificial layer is etched with the etching solution, to thereby obtain a diaphragm body formed of the multilayer structure, which functions on the vacuum chamber, and a surface of a silicon substrate below a first opening of a first insulating film is etched to thereby form the space which is to serve as the vacuum chamber and a diaphragm stopper disposed in the space, protruding toward near the center of the diaphragm body.

Abstract: A device for measuring environmental forces, and a method for fabricating the same, is disclosed that comprises a device wafer, the device wafer comprising a first device layer separated from a second device layer by a first insulation layer. The first device wafer is bonded to an etched substrate wafer to create a suspended diaphragm and boss, the flexure of which is determined by an embedded sensing element.

Abstract: The present invention discloses a MEMS (Micro-Electro-Mechanical System) chip and a method for making the MEMS chip. The MEMS chip comprises: a first substrate having a first surface and a second surface opposing each other; a microelectronic device area on the first surface; a first MEMS device area on the second surface; and a conductive interconnection structure electrically connecting the microelectronic device area and the first MEMS device area.

Abstract: In one embodiment, a sensor device includes a bulk silicon layer, a first doped region of the bulk silicon layer of a first dopant type, a second doped region of the bulk silicon layer of a second dopant type, wherein the first dopant type is a type of dopant different from the second dopant type, the second doped region located at an upper surface of the bulk silicon layer and having a first doped portion bounded by the first doped region, a first cavity portion directly above the second doped region, and an upper electrode formed in an epitaxial layer, the upper electrode directly above the first cavity portion.

Abstract: A MEMS device has a first member that is movable relative to a second member. At least one of the first member and the second member has exposed silicon carbide with a water contact angle of greater than about 70 degrees.

Abstract: A MEMS device includes a substrate. The substrate has a plurality of through holes in the substrate within a diaphragm region and optionally an indent space from the second surface at the diaphragm region. A first dielectric structural layer is then disposed over the substrate from the first surface, wherein the first dielectric structural layer has a plurality of openings corresponding to the through holes, wherein each of the through holes remains exposed by the first dielectric structural layer. A second dielectric structural layer with a chamber is disposed over the first dielectric structural layer, wherein the chamber exposes the openings of the first dielectric structural layer and the through holes of the substrate to connect to the indent space. A MEMS diaphragm is embedded in the second dielectric structural layer above the chamber, wherein an air gap is formed between the substrate and the MEMS diaphragm.

Abstract: Semiconductor devices are formed with a nano-electro-mechanical system (NEMS) logic or memory on a bulk substrate. Embodiments include forming source/drain regions directly on a bulk substrate, forming a fin connecting the source/drain regions, forming two gates, one on each side of the fin, the two gates being insulated from the bulk substrate, and forming a substrate gate in the bulk substrate. The fin is separated from each of the two gates and the substrate gate with an air gap.

Abstract: A capacitive pressure sensor includes: a semiconductor substrate having a reference pressure chamber formed therein; a diaphragm which is formed in a front surface of the semiconductor substrate and has a ring-like peripheral through hole penetrating between the front surface of the semiconductor substrate and the reference pressure chamber and defining an upper electrode and a plurality of central through holes; a peripheral insulating layer which fills the peripheral through hole and electrically isolates the upper electrode from other portions of the semiconductor substrate; and a central insulating layer which fills the central through holes.

Abstract: In a method of manufacturing a semiconductor integrated circuit device having an MEMS element over a single semiconductor chip, the movable part of the MEMS element is fixed before the formation of a rewiring. After formation of the rewiring, the wafer is diced. Then, the movable part of the MEMS element is released by etching the wafer.

Abstract: The micro-electromechanical semiconductor component is provided with a first semiconductor substrate, which has an upper face, and a second semiconductor substrate, which has an upper face. Both semiconductor substrates are bonded resting on the upper faces thereof. A cavity is introduced into the upper face of at least one of the two semiconductor substrates. The cavity is defined by lateral walls and opposing top and bottom walls, which are formed by the two semiconductor substrates. The top or the bottom wall acts as a reversibly deformable membrane and an opening extending through the respective semiconductor substrate is arranged in the other of said two walls of the cavity.

Abstract: The present invention provides a MEMS structure comprising confined sacrificial oxide layer and a bonded Si layer. Polysilicon stack is used to fill aligned oxide openings and MEMS vias on the sacrificial layer and the bonded Si layer respectively. To increase the design flexibility, some conductive polysilicon layer can be further deployed underneath the bonded Si layer to form the functional sensing electrodes or wiring interconnects. The MEMS structure can be further bonded to a metallic layer on top of the Si layer and the polysilicon stack.

Abstract: A method of fabricating a micro-electrical-mechanical system (MEMS) apparatus on a substrate (10) comprises the steps of processing the substrate (10) so as to fabricate an electronic circuit (11); depositing a first electrode (15) that is operably coupled with the electronic circuit (11); depositing a membrane (16) so that it is mechanically coupled to the first electrode (15); applying a sacrificial layer (50); depositing a structural layer (18) and a second electrode (17) that is operably coupled with the electronic circuit (11) so that the sacrificial layer (50) is disposed between the membrane (16) and the structural layer (18) so as to form a preliminary structure; singulating the substrate (10); and removing the sacrificial layer (50) so as to form a MEMS structure, in which the step of singulating the substrate (10) is carried out before the step of removing the sacrificial layer (50).

Abstract: A method is described for manufacturing a micromechanical component. The method includes providing a first substrate, forming a first connecting structure on the first substrate, and forming a microstructure on the first substrate after forming the first connecting structure. The microstructure has at least one movable functional element. The method further includes providing a second substrate having a second connecting structure, and joining the first and second substrates by carrying out a bonding process, the first and second connecting structures being joined to form a common connecting structure, and a sealed cavity being formed in the region of the microstructure. The method provides that the first connecting structure takes the form of a buried connecting structure extending up to an upper surface of the first substrate. Also described is a related micromechanical component.

Abstract: The present invention describes a method for producing a micromechanical capacitive pressure transducer and a micromechanical component produced by this method. First, a first electrode is produced in a doped semiconductor substrate. In a further method step, a diaphragm with a second electrode is produced at the surface of the semiconductor substrate. Furthermore, it is provided to apply a first layer, which preferably is made of dielectric material, on the diaphragm and the semiconductor substrate. With the aid of this first layer, the diaphragm and the semiconductor substrate of the finished micromechanical capacitive pressure transducer are mechanically connected to one another directly or indirectly. Furthermore, a buried cavity is produced in the semiconductor substrate between the first and second electrode.

Abstract: The present disclosure provides a method for fabricating a MEMS device including multiple bonding of substrates. In an embodiment, a method includes providing a micro-electro-mechanical systems (MEMS) substrate including a first bonding layer, providing a semiconductor substrate including a second bonding layer, and providing a cap including a third bonding layer. The method further includes bonding the MEMS substrate to the semiconductor substrate at the first and second bonding layers, and bonding the cap to the semiconductor substrate at the second and third bonding layers to hermetically seal the MEMS substrate between the cap and the semiconductor substrate. A MEMS device fabricated by the above method is also provided.

Abstract: A simple and economical method for manufacturing very thin capped MEMS components. In the method, a large number of MEMS units are produced on a component wafer. A capping wafer is then mounted on the component wafer, so that each MEMS unit is provided with a capping structure. Finally, the MEMS units capped in this way are separated to form MEMS components. A diaphragm layer is formed in a surface of the capping wafer by using a surface micromechanical method to produce at least one cavern underneath the diaphragm layer, support points being formed that connect the diaphragm layer to the substrate underneath the cavern. The capping wafer structured in this way is mounted on the component wafer in flip chip technology, so that the MEMS units of the component wafer are capped by the diaphragm layer. The support points are then cut through in order to remove the substrate.

Abstract: A semiconductor device includes a substrate including a cavity and a first material layer over at least a portion of sidewalls of the cavity. The semiconductor device includes an oxide layer over the substrate and at least a portion of the sidewalls of the cavity such that the oxide layer lifts off a top portion of the first material layer toward a center of the cavity.

Abstract: A MEMS differential pressure sensing element is provided by two separate silicon dies attached to opposite sides of a silicon or glass spacer. The spacer is hollow. If the spacer is silicon, the dies are preferably attached to the hollow spacer using silicon-to-silicon bonding provided in part by silicon oxide layers. If the spacer is glass, the dies can be attached to the hollow spacer using anodic bonding. Conductive vias extend through the layers and provide electrical connections between Wheatstone bridge circuits formed from piezoresistors in the silicon dies.