Abstract:
A high-temperature pressure sensor that includes a dielectric layer. The pressure sensor also includes a substrate capable of withstanding temperatures greater than 450° C. without entering a phase change, at least one semiconducting material deposited on the sapphire substrate, and a silicon dioxide layer deposited over the semiconducting material. One aspect of the pressure sensor includes a second semiconducting material.
Abstract:
A three-dimensional micro-electro-mechanical-systems (MEMS) capacitive bending and axial strain sensor capacitor is described. Two independent comb structures, incorporating suspended polysilicon interdigitated fingers, are fabricated simultaneously on a substrate that can displace independently of each other while attached to a substrate undergoing bending or axial deformation. A change in spacing between the interdigitated fingers will output a change in capacitance of the sensor and is the primary mode of operation of the device. On the bottom and to the end of each comb structure, a glass pad is attached to the comb structure to allow for ample surface area for affixing the sensor to a substrate. During fabrication, tethers are used to connect each comb structure to maintain equal spacing between the fingers before attachment to the substrate. After attachment, the tethers are broken to allow independent movement of each comb structure.
Abstract:
Sensor cells are arranged in an array in an organic semiconductor layer. Row and column select circuitry addresses the cells of the array one cell at a time to determine the presence of an object, such as a fingerprint ridge or valley, contacting or proximate to a sensing surface above each cell. Control circuitry can be provided in a companion silicon chip or in a second layer of organic semiconductor material to communicate with the array and an associated system processor. The array of sensor cells can be fabricated using a flexible polymer substrate that is peeled off and disposed of after contacts have been patterned on the organic semiconductor layer. The organic semiconductor layer can be used with a superimposed reactive interface layer to detect specific chemical substances in a test medium.
Abstract:
A force or pressure transducer is disclosed. In one embodiment, the transducer has a substrate, a dielectric material disposed on the substrate, a spacing member disposed on the dielectric material, and a resilient element disposed on the dielectric material and the spacing member. A portion of the resilient element is separated from the dielectric material, and a portion of the resilient element is in contact with the dielectric material. The contact area between the resilient element and the dielectric material varies in response to movement of the resilient element. Changes in the contact area alter the capacitance of the transducer, which can be measured by circuit means.
Abstract:
A sensor comprises a semiconductor pellet (10) including a working portion (11) adapted to undergo action of a force, a fixed portion (13) fixed on the sensor body, and a flexible portion (13) having flexibility formed therebetween, a working body (20) for transmitting an exterted force to the working portion, and detector means (60-63) for transforming a mechanical deformation produced in the semiconductor pellet to an electric signal to thereby detect a force exerted on the working body as an electric signal. A signal processing circuit is applied to the sensor. This circuit uses analog multipliers (101-109) and analog adders/subtracters (111-113), and has a function to cancel interference produced in different directions. Within the sensor, two portions (E3, E4-E8) located at positions opposite to each other and producing a displacement therebetween by action of a force are determined. By exerting a coulomb force between both the portions, the test of the sensor is carried out. Further, a pedestal (21, 22) is provided around the working body (20). The working body and the pedestal are located with a predetermined gap or spacing therebetween. A displacement of the working body is caused to limitatively fall within a predetermined range Corresponding to the spacing. The working body and the pedestal are provided by cutting a same common substrate (350, 350null).
Abstract:
A force or pressure transducer is disclosed. In one embodiment, the transducer has a substrate, a dielectric material disposed on the substrate, a spacing member disposed on the dielectric material, and a resilient element disposed on the dielectric material and the spacing member. A portion of the resilient element is separated from the dielectric material, and a portion of the resilient element is in contact with the dielectric material. The contact area between the resilient element and the dielectric material varies in response to movement of the resilient element. Changes in the contact area alter the capacitance of the transducer, which can be measured by circuit means.
Abstract:
A capacitive strain sensor comprises a substrate (119) and a pair of interdigital electrode capacitors (209, 209A) formed on the substrate. A dielectric thick film (129) having a uniform thickness and made of a material the dielectric constant of which varies with strain is provided on an elastic body having a flat or curved surface on the substrate (119). A block (318) for preventing strain from being produced is secured to one end of the substrate (119); a weight (329) is secured to the other end. The capacitors (209, 209A) are formed by interdigitally arranging a pair of electrodes being parallel linear electrodes of linear conductors on the substrate.
Abstract:
A process for separating at least two elements of a structure. The two elements are in contact with one another along an interface and are fixed to one another by interatomic bonds at their interface. An ion implantation is performed in order to introduce ions into the structure with an adequate energy for them to reach the interface and with an adequate dose to break the interatomic bonds. This brings about at the interface, the formation of a gaseous phase having an adequate pressure to permit the separation of the two elements.
Abstract:
A semiconductor chip has a membrane mounted on supports that are held in the material of the chip so that the membrane is supported at a space from the chip. The membrane may be a metal layer. The supports are columns or webs that extend into the chip material. Electrical connections to the membrane may be made by conductive supports.
Abstract:
A double pinned micromachined sensor (11) which utilizes a laminated film (27) having overall tensile strength formed on top of a silicon substrate (16). The laminated film (27) comprises a layer of silicon nitride (18) encapsulated by two layers of polysilicon (19, 21), the silicon nitride (18) providing overall tension for the laminated film. The laminated film (27) is supported above the silicon substrate by support posts (17) and is selectively etched to form a sensor (11, 13).