Abstract:
Disclosed are capacitive pressure probes or sensors for high temperature applications. The capacitive pressure sensors of the present invention include, inter alia, a sapphire diaphragm which is disposed within an interior sensing chamber of the probe housing and has a first electrode formed on a central portion thereof. The central portion of the diaphragm and the first electrode are adapted and configured to deflect in response to pressure variations encountered within an interior sensing chamber and by the pressure sensor. A sapphire substrate which has a second electrode formed thereon is fused to the sapphire diaphragm about its periphery to form a sapphire stack and to define a reference chamber therebetween. Prior to fusing the sapphire diaphragm to the sapphire substrate, all contact surfaces are chemically treated and prepared using plasma activation, so as to create a bonding layer and to reduce the temperature required for the fusion.
Abstract:
A pendulous capacitive accelerometer including a substrate having a substantially planar upper surface with an electrode section, and a sensing plate having a central anchor portion supported on the upper surface of the substrate to define a hinge axis. The sensing plate includes a solid proof mass on a first side of the central anchor portion and a substantially hollow proof mass on a second side of the central anchor portion, providing for reduced overall chip size and balanced gas damping. The solid proof mass has a first lower surface with a first electrode element thereon, and the substantially hollow proof mass has a second lower surface with a second electrode element thereon. Both the solid proof mass and the hollow proof mass have the same capacitive sensing area. The sensing plate rotates about the hinge axis relative to the upper surface of the substrate in response to an acceleration.
Abstract:
Disclosed is a capacitive pressure probe for high temperature applications, such as for use in a gas turbine engine. The capacitive probe or pressure sensor of the present invention includes, inter alia, a sensor housing that defines an interior sensing chamber having a pressure port and an interior reference chamber positioned adjacent to a sensing electrode. The reference chamber is separated from the sensing chamber by a deflectable diaphragm made from Haynes 230 alloy, wherein the deflection of the diaphragm in response to an applied pressure in the sensing chamber corresponds to a change in capacitance value detected by the sensing electrode.
Abstract:
A pressure sensor including a movable component that is configured to move when the pressure sensor is exposed to differential pressure thereacross, and a pressure sensing component located on the movable component. The pressure sensing component includes an electrically conductive electron gas which changes its electrical resistance thereacross upon movement of the movable component. The pressure sensor is configured such that leads can be coupled to the pressure sensing component and the pressure sensing component can output a signal via the leads, the signal being related to a pressure to which the pressure sensor is exposed.
Abstract:
A micro mirror array including an upper wafer portion having a plurality of movable reflective surfaces located thereon, the upper wafer portion defining a coverage area in top view. The array further includes a lower wafer portion located generally below and coupled to the upper wafer portion. The lower wafer portion includes at least one connection site located thereon, the at least one connection site being electrically or operatively coupled to at least one component which can control the movement of at least one of the reflective surfaces. The at least one connection site is not generally located within the coverage area of the upper wafer portion.
Abstract:
Disclosed is a capacitive pressure probe for high temperature applications, such as for use in a gas turbine engine. The capacitive probe or pressure sensor of the present invention includes, inter alia, a sensor housing that defines an interior sensing chamber having a pressure port and an interior reference chamber positioned adjacent to a sensing electrode. The reference chamber is separated from the sensing chamber by a deflectable diaphragm made from Haynes 230 alloy, wherein the deflection of the diaphragm in response to an applied pressure in the sensing chamber corresponds to a change in capacitance value detected by the sensing electrode.
Abstract:
A harsh environment transducer including a substrate having a first surface and a second surface, wherein the second surface is in communication with the environment. The transducer includes a device layer sensor means located on the substrate for measuring a parameter associated with the environment. The sensor means including a single crystal semiconductor material having a thickness of less than about 0.5 microns. The transducer further includes an output contact located on the substrate and in electrical communication with the sensor means. The transducer includes a package having an internal package space and a port for communication with the environment. The package receives the substrate in the internal package space such that the first surface of the substrate is substantially isolated from the environment and the second surface of the substrate is substantially exposed to the environment through the port. The transducer further includes a connecting component coupled to the package and a wire electrically connecting the connecting component and the output contact such that an output of the sensor means can be communicated. An external surface of the wire is substantially platinum, and an external surface of at least one of the output contact and the connecting component is substantially platinum.
Abstract:
A detector including a base having a recess formed therein and a diaphragm generally extending across the recess. The detector further includes an infrared sensitive component or a piezoelectric or piezoresistive element located on, above or supported by the diaphragm. The diaphragm includes a material which is generally resistant to liquid chemical etchants and which has a thermal conductivity of less than about 0.005 Wcm−1K−1.