Abstract: The present invention provides a proportional microvalve having a first, second and third layer, and having high aspect ratio geometries. The first layer defines a cavity with inlet and outlet ports. The second layer, doped to have a low resistivity and bonded between the first and third layers, defines a cavity having a flow area to permit fluid flow between the inlet and outlet ports. The second layer further defines an actuatable displaceable member, and one or more thermal actuators for actuating the displaceable member to a position between and including an open and a closed position to permit or occlude fluid flow. The third layer provides one wall of the cavity and provides electrical contacts for electrically heating the thermally expandable actuators. The thermal actuators and the displaceable member have high aspect ratios and are formed by deep reactive ion etching such that they are displaceable in the plane of the second layer while being very stiff out of the plane.

Abstract: The present invention provides a proportional microvalve having a first, second and third layer, and having high aspect ratio geometries. The first layer defines a cavity with inlet and outlet ports. The second layer, doped to have a low resistivity and bonded between the first and third layers, defines a cavity having a flow area to permit fluid flow between the inlet and outlet ports. The second layer further defines an actuatable displaceable member, and one or more thermal actuators for actuating the displaceable member to a position between and including an open and a closed position to permit or occlude fluid flow. The third layer provides one wall of the cavity and provides electrical contacts for electrically heating the thermally expandable actuators. The thermal actuators and the displaceable member have high aspect ratios and are formed by deep reactive ion etching such that they are displaceable in the plane of the second layer while being very stiff out of the plane.

Abstract: A variable capacitor. The variable capacitor has a movable capacitor electrode including a major surface and a fixed capacitor electrode including a major surface. The major surface of the fixed capacitor electrode is opposite the major surface of the movable capacitor electrode and is separated therefrom by a gap. The major surface of the movable capacitor electrode includes a rigidity-increasing feature. The rigidity-increasing feature further provides a capacitance-increasing topography and reduces snap-together of the capacitor electrodes.

Abstract: A tunable capacitor. The tunable capacitor has a first fixed capacitor electrode and a second fixed capacitor electrode opposite to one another. The tunable capacitor also has a movable element formed of a conductive material. The movable element is moveable between the first fixed capacitor electrode and the second fixed capacitor electrode to adjust the capacitance between the first fixed capacitor electrode and the second fixed capacitor electrode.

Abstract: A microvalve device for controlling fluid flow in a fluid circuit. The microvalve device comprises a body having a cavity formed therein. The body further has first and second pilot ports placed in fluid communication with the cavity. The body also has first and second primary ports placed in fluid communication with the cavity. Each port is adapted for connection with a designated fluid source. A pilot valve supported by the body is movably disposed in the cavity for opening and closing the first and second pilot ports. An actuator is operably coupled to the pilot valve for moving the pilot valve. A microvalve is positioned by the fluid controlled by the pilot valve. The microvalve is a slider valve having a first end and a second end. The slider valve is movably disposed in the cavity for movement between a first position and a second position. The first end of the slider valve is in fluid communication with the first and second pilot ports when the first and second pilot ports are open.

Abstract: A tunable capacitor. The tunable capacitor has a first fixed capacitor electrode and a second fixed capacitor electrode opposite to one another. The tunable capacitor also has a movable element formed of a conductive material. The movable element is moveable between the first fixed capacitor electrode and the second fixed capacitor electrode to adjust the capacitance between the first fixed capacitor electrode and the second fixed capacitor electrode.

Abstract: A variable capacitor. The variable capacitor has a movable capacitor electrode including a major surface and a fixed capacitor electrode including a major surface. The major surface of the fixed capacitor electrode is opposite the major surface of the movable capacitor electrode and is separated therefrom by a gap. The major surface of the movable capacitor electrode includes a rigidity-increasing feature. The rigidity-increasing feature further provides a capacitance-increasing topography and reduces snap-together of the capacitor electrodes.

Abstract: The present invention provides a proportional microvalve having a first, second and third layer, and having high aspect ratio geometries. The first layer defines a cavity with inlet and outlet ports. The second layer, doped to have a low resistivity and bonded between the first and third layers, defines a cavity having a flow area to permit fluid flow between the inlet and outlet ports. The second layer further defines an actuatable displaceable member, and one or more thermal actuators for actuating the displaceable member to a position between and including an open and a closed position to permit or occlude fluid flow. The third layer provides one wall of the cavity and provides electrical contacts for electrically heating the thermally expandable actuators. The thermal actuators and the displaceable member have high aspect ratios and are formed by deep reactive ion etching such that they are displaceable in the plane of the second layer while being very stiff out of the plane.

Abstract: The present invention provides a proportional microvalve having a first, second and third layer, and having high aspect ratio geometries. The first layer defines a cavity with inlet and outlet ports. The second layer, doped to have a low resistively and bonded between the first and third layers, defines a cavity having a flow area to permit fluid flow between the inlet and outlet ports. The second layer further defines an actuatable displaceable member, and one or more thermal actuators for actuating the displaceable member to a position between and including an open and a closed position to permit or occlude fluid flow. The third layer provides one wall of the cavity and provides electrical contacts for electrically heating the thermally expandable actuators. The thermal actuators and the displaceable member have high aspect ratios and are formed by deep reactive ion etching such that they are displaceable in the plane of the second layer while being very stiff out of the plane.

Abstract: Disclosed is a microvalve suitable for use in high pressure applications such as refriigeration. The microvalve has a displaceable member that slides across an inlet port, thereby creating an orifice. A pressure-equalizing contour is positioned beneath the displaceable member and is in fluid contact with the inlet port. The pressure on the displaceable member from the inlet port is equalized by the pressure from the pressure-equalizing contour. Consequently, the microvalve can be configured with its inlet port and outlet port on opposite sides of the microvalve. Pressures in the x and y direction are also equalized because of recesses that permit fluid from the inlet to contact all faces of the displaceable member.

Abstract: The present invention provides a proportional microvalve having a first, second and third layer, and having high aspect ratio geometries. The first layer defines a cavity with inlet and outlet ports. The second layer, doped to have a low resistivity and bonded between the first and third layers, defines a cavity having a flow area to permit fluid flow between the inlet and outlet ports. The second layer further defines an actuatable displaceable member, and one or more thermal actuators for actuating the displaceable member to a position between and including an open and a closed position to permit or occlude fluid flow. The third layer provides one wall of the cavity and provides electrical contacts for electrically heating the thermally expandable actuators. The thermal actuators and the displaceable member have high aspect ratios and are formed by deep reactive ion etching such that they are displaceable in the plane of the second layer while being very stiff out of the plane.

Abstract: A surface and/or bulk micromachined hermetically sealed cavity containing at least one suspended structure in a low pressure ambient, and the associated fabrication method. The cavity is bounded by a thin-film membrane and a substrate which may have a recess. The method can be used for the production, for example, of thermionic-emission vacuum tubes, gas filled tubes and electromechanical devices. In vacuum tubes the cathode is a suspended refractory filament. Other electrodes may also be suspended. In electromechanical devices the suspended members may be cantilever beams capable of low friction motion.