Delco Electronics Corporation

Delphi Technologies, Inc.

Douglas Ray Sparks

John Carl Christenson

Dan Wesley Chilcott

Mark Billings Kearney

William J Baney

Steven E Staller

Ronald E Brown

Robert Lawrence Healton

James Werstler Siekkinen

Dan W Chilcott

Shing Yeh

Marion Edmond Ellis

Hamid Reza Borzabadi

Lewis Henry Little

Larry Lee Jordan

Tracy Adam Noll

Andres Deogracias Viduya

James M Himelick

George Qin Jiang

Ruth Ellen Beni

Anthony Alan Duffer

A semiconductor device and method by which a device chip with a micromachine is directly surface mounted to a circuit board. A capping chip is bonded to the device chip and encloses the micromachine. The capping chip has a first surface facing the device chip, an oppositely-disposed second surface, and electrical interconnects through the capping chip between the first and second surfaces. The electrical interconnects electrically communicate with runners on the device chip that are electrically connected to the micromachine, thereby providing a signal path from the micromachine to the exterior of the device. The capping chip further includes bond pads for electrical communication with the electrical interconnects. With the bond pads, the capping chip can be surface mounted to a circuit board by reflowing solder bumps formed on the bond pads. Depending on the placement of the bond pads on the capping chip, the semiconductor device can be mounted to the circuit board with the capping chip between the device chip and circuit board, or the semiconductor device can be mounted with one side of the device attached to the circuit board.

Surface mount package for a micromachined device

A multi-sensor module ( ) includes a housing ( ) with a plurality of vehicle operating condition sensors (S -S ) mounted therein and a signal processing circuit ( ) also mounted therein which receives sensor signals provided by the plurality of sensors (S -S ). The signal processing circuit ( ) is operable to produce at an output thereof ( ) a time-division multiplexed signal representative of the various sensor signals according to a vehicle data bus communications protocol. The signal processing circuit output is connected to an electrical connector ( ) adapted for connection to an existing vehicle data bus ( ) which is further connected to a vehicle control computer ( ). The signal processing circuit ( ) is accordingly operable to broadcast on the vehicle data bus ( ) sensor information provided by each of the sensors (S -S ) mounted within the module ( ).

Multi-sensor module for communicating sensor information over a vehicle data bus

A method by which semiconductor wafers (10, 12) can be solder bonded to form a semiconductor device, such as a sensor with a micromachined structure (14). The method entails forming a solderable ring (18) on the mating surface of a device wafer (10), such that the solderable ring (18) circumscribes the micromachine (14) on the wafer (10). A solderable layer (20, 26, 28) is formed on a capping wafer (12), such that at least the mating surface (24) of the capping wafer (12) is entirely covered by the solderable layer (20, 26, 28). The solderable layer (20, 26, 28) can be formed by etching the mating surface (24) of the capping wafer (12) to form a recess (16) circumscribed by the mating surface (24), and then forming the solderable layer (26) to cover the mating surface (24) and the recess (16) of the capping wafer (12). Alternatively, the solderable layer (28) can be formed by depositing a solderable material to cover the entire lower surface of the capping wafer (12), patterning the resulting solderable layer (28) to form an etch mask on the capping wafer (12), and then to form the recess (16), such that the solderable layer (28) covers the mating surface (24) but not the surfaces of the recess (16).

Process for bonding micromachined wafers using solder

A sensor (10) having polysilicon strain-sensing elements (20) on a metal diaphragm (16). A thick-film insulating layer (18) covers the metal diaphragm (16), and thin-film polysilicon resistive elements (20) are formed on the thick-film insulating layer (18). Thick-film conductors (22) are formed on the thick-film insulating layer (18) and contact the thin-film polysilicon resistive elements (20) to form electrical interconnects to the resistive elements (20). The thick-film conductors (22) preferably contain silicon in order to reduce diffusion of silicon from the polysilicon resistive elements (20). The thick-film insulating layer (18) may be made up of a number of individual thick-film layers, the uppermost of which is stable and nonreactive with the thin-film polysilicon resistive elements (20) and the thick-film conductors (22) at temperatures of at least 600.degree. C. A passivation layer (24) overlies the thin-film polysilicon resistive elements (20) and the thick-film conductors (22). The sensor (10) can be made sufficiently rugged to be used as a structural member of a fluid-containing vessel.

Metal diaphragm sensor with polysilicon sensing elements and methods

An all-silicon monolithic capacitive absolute pressure-sensing device and method for making the same. The device employs a single-crystal silicon diaphragm that serves at a flexible capacitor plate of a variable capacitor. The diaphragm is bonded to a single-crystal silicon wafer to overlie a cavity etched into the wafer. A fixed capacitor plate of the variable capacitor is formed by a heavily-doped region at the bottom of the cavity. A thin dielectric layer is grown on the fixed capacitor plate to complete the capacitor. The cavity has a minimal depth such that the fixed capacitor plate provides overpressure protection for the diaphragm. At least a portion of the operating range of the pressure sensor occurs while the diaphragm is contacting the doped region. As a result, the capacitive output signal of the pressure sensor is produced by changes in contact area between the diaphragm and a thin dielectric situated on the doped region in response to pressure applied to the diaphragm.

All-silicon capacitive pressure sensor

A media-compatible sensing structure (210) that employs strain-sensing elements (222) formed in or on a silicon chip (212). The sensor (210) generally includes a metal body (214) having a diaphragm (216) and an edge (226) formed by an abrupt change in the thickness of the metal body (214) in a direction normal to the diaphragm (216). The silicon chip (212) is secured directly to the metal diaphragm (216) and has at least one strain-sensing element (222) aligned with the edge (226) of the body (214) in the direction normal to the diaphragm (216), such that movement of the diaphragm (216) induces strain in the silicon chip (212) that is localized at the strain-sensing element (222). The chip (212) preferably includes a groove (234) in its surface (212) facing the diaphragm (216) and between the strain-sensing element (222) and the metal body (214), such that strain induced in the chip (212) by movement of the diaphragm (216) is further concentrated in the region of the chip (212) containing the strain-sensing element (222). The chip (212) is preferably attached to the metal diaphragm (216) with a bonding material (236). To promote adhesion of the chip (212) to the diaphragm (216), the chip (212) preferably has recesses (240) in its surface facing the diaphragm (216) to create an interlocking effect between the bonding material (236) and the chip (212).

Sensor with silicon strain gage

A silicon sensing cell (12) capable of sensing force and/or displacement, and particular embodiments of the sensing cell (12) for particular force and/or displacement-sensing applications. The sensing cell (12) generally includes a diaphragm (18), a silicon sensing element (28) operatively associated with the diaphragm (18) to sense strain or deflection of the diaphragm (18), a base (14) supporting the diaphragm (18) so that the base (14) and the diaphragm (18) define a recess (22), and a force-distributing member (20) within the recess (22) and contacting the diaphragm (18). The diaphragm (18) is preferably single-crystal silicon, and the sensing element (28) can be a piezoresistive, piezoelectric or capacitive element preferably formed in the diaphragm (18) using semiconductor fabrication processes. With appropriate adaptations, the sensing cell (12) can be made suitable for automotive applications such as seat occupancy sensing, brake-by-wire and acceleration-by-wire pedal systems, and media-compatible high-pressure sensing in brake, oil and transmission fluid applications.

Silicon force and displacement sensor

A method for making and vacuum packaging a silicon micromachined motion sensor, such as a gyroscope, at the chip level. The method involves micromachining a trench-isolated sensing element in a sensing chip, and then attaching a circuit chip to enclose the sensing element. Solder bumps serve to attach the circuit chip to the sensing chip, form a hermetic seal to enable vacuum-packaging of the sensor, and electrically interconnect the sensing chip with the circuit chip. Conductive runners formed on the enclosed surface of the circuit chip serve to electrically interconnect the sensing element with its associated sensing structures.

Silicon micromachined motion sensor and method of making

A method for concurrently forming a micromachine element and an integrated circuit device on the same substrate, such that fabrication of the micromachine element and the circuit device requires a minimal number of processing steps. The method is adapted for forming sensing devices, such as accelerometers and pressure sensors, which utilize a small micromachine element, such as a bridge, cantilevered beam, suspended mass, membrane or capacitive element that is supported over a cavity formed in the silicon substrate. Piezoresistors used to detect the deflection of the micromachine element are formed simultaneously with elements of the integrated circuit devices, such that a minimal number of processing steps are required.

One-chip integrated sensor process

Method for making an all-silicon capacitive pressure sensor

A silicon flow sensor is provided having an uncomplicated design and construction, while also exhibiting a desirable level of sensitivity for use in automotive applications. The primary sensing component is preferably formed by a single silicon chip on which associated signal conditioning and compensating circuitry can be provided. The chip includes a base region from which a vane is cantilevered so as to be adapted to deflect in either of two directions when impinged by fluid flow. A beam region is present intermediate the vane and the base region on which a strain sensing element is present, such that strain occurring in the beam region as a result of vane deflection is sensed to indicate the degree to which the vane is deflected. The construction of the flow sensor is such that its sensitivity can be readily modified during its manufacture in order to optimize the sensor for its intended use.

Silicon flow sensor

A method for forming a motion sensor for sensing motion or acceleration of a body, such as the type used in VCR cameras and onboard automotive and aerospace safety control system or navigational system. The motion sensor includes a sensing structure, such as a resonating metal ring and spring structure, which is supported above a substrate and circumscribed by an electrode pattern. The sensing structure is supported above the substrate by an electrically-conductive post located at the axis of motion. The electrodes serve to drive the ring into resonance, balance the sensing structure by inducing stiffness in the ring and springs, and sense rotary motion of the ring. To electrically interconnect the ring with the electrodes, three non-dielectric layers are formed on the substrate to form a radial conductor pattern, a concentric conductor pattern and a bias plane beneath the sensing structure. In accordance with this invention, one of the non-dielectric layers is a planarized doped polysilicon layer, while the remaining two non-dielectric layers are planarized and passivated metal layers. Additional accessories for enhancing the performance and reliability of the motion sensor include one or more g-stops which prevent excessive deflection, and particle getters.

Method for forming a micromachine motion sensor

A method is disclosed for micromachining the surface of a silicon substrate which encompasses a minimal number of processing steps. The method involves a preferential etching process in which a chlorine plasma etch is capable of laterally etching an N+ buried layer beneath the surface of the bulk substrate. Such a method is particularly suitable for forming sensing devices which include a small micromachined element, such as a bridge, cantilevered beam, membrane, suspended mass or capacitive element, which is supported over a cavity formed in a bulk silicon substrate. The method also permits the formation of such sensing devices on the same substrate as their controlling integrated circuits. This invention also provides novel methods by which such structures can be improved, such as through optimizing the dimensional characteristics of the micromachined element or by encapsulating the micromachined element.

Micromachined integrated pressure sensor with oxide polysilicon cavity

A method for micromachining the surface of a silicon substrate which encompasses a minimal number of processing steps. The method involves a preferential etching process in which a chlorine plasma etch is capable of laterally etching an N+ buried layer beneath the surface of the bulk substrate. Such a method is particularly suitable for forming sensing devices which include a small micromachined element, such as a bridge, cantilevered beam, membrane, suspended mass or capacitive element, which is supported over a cavity formed in a bulk silicon substrate. The method also permits the formation of such sensing devices on the same substrate as their controlling integrated circuits. This invention also provides novel methods by which such structures can be improved, such as through optimizing the dimensional characteristics of the micromachined element or by encapsulating the micromachined element.

Method of micromachining an integrated sensor on the surface of a

A method for dielectrically isolating a semiconductor integrated circuit is provided. Each integrated circuit is substantially surrounded by silicon oxide sidewalls which have been appropriately doped to be of an opposite conductivity type as the surrounding substrate. The doped silicon oxide sidewalls are formed prior to the growth of epitaxial silicon within the sidewalls. Upon deposition of the epitaxial silicon the dopant within the oxide sidewalls diffuses into the adjacent epitaxial silicon, thereby resulting in a heavily doped, low resistivity region of epitaxial silicon adjacent to and along the entire length of the oxide sidewall. This heavily doped region results in the substantial elimination of charge-depleting parasitic currents along the sidewalls during use of the integrated circuit. In addition, the heavily doped, low resistivity epitaxial region provides an electrically conductive contact to a buried layer within an integrated circuit having such a buried layer. Extremely thin and long, contacts can be made to the buried layer using this method, without the traditional need for long diffusion times which result in excessively wide diffusion zones.

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Kokomo, IN, United States of America

Douglas Ray Sparks