Abstract: An ultracapacitor comprises two solid, nonporous current collectors, two porous electrodes separating the collectors, a porous separator between the electrodes and an electrolyte occupying the pores in the electrodes and separator. At least one of the current collectors comprises a conductive metal substrate coated with a metal nitride, carbide or boride coating.

Abstract: An ultracapacitor having two solid, nonporous current collectors, two porous electrodes separating the collectors, a porous separator between the electrodes and an electrolyte occupying the pores in the electrodes and separator. At least one of the current collectors comprises a conductive metal substrate coated with a metal nitride, carbide or boride coating.

Abstract: An accelerometer fabricated from silicon which is responsive to the three orthogonal components of an applied force. A method is also disclosed for etching the accelerometer from a single silicon substrate. Three rectangular beams or cantilevers are formed each having vertical sidewalls lying in crystalline planes orthogonal to one another. Each of the beams is directly responsive to one of the three orthogonal force components.

Abstract: An accelerometer fabricated from silicon which is responsive to the three orthogonal components of an applied force. A method is also disclosed for etching the accelerometer from a single silicon substrate. Three rectangular beams or cantilevers are formed each having vertical sidewalls lying in crystalline planes orthogonal to one another. Each of the beams is directly responsive to one of the three orthogonal force components.

Abstract: An electrically controllable valve etched from two silicon substrates includes an inlet orifice communicating with two outlet orifices through a channel etched into the substrates. A mesa, in operative alignment with the inlet orifice, is suspended between the channel and a sealed recess by a diaphragm. The mesa has a permanent magnet attached thereto in operative alignment with a flat helical coil deposited on another substrate which seals the recess. Electronic control circuitry passes current through the coil in an appropriate direction to deflect the mesa in a corresponding direction for either opening or closing the valve. Equalized pressure is maintained on opposing mesa surfaces by a passageway communicating between the sealed recess and an outer surface of the valve thereby minimizing the force required to operate the valve.

Abstract: A method for anisotropically etching an aperture into a monocrystaline substrate such that the angle of the aperture plane with respect to the nominal crystaline planes of the substrate may be preselected. Etchant pits through opposing planar surfaces are offset from one another by a preselected longitudinal offset trigonometrically related to the desired aperture angle. Other selected parameters trigonometrically related to the aperture plane include: the intersecting angle of the intersecting crystaline planes with the nominal crystaline planes; substrate thickness; and depth of each of the etchant pits.

Abstract: A silicon substrate having {100} nominal crystalline planes is anisotropically etched to form a pair of V-shaped grooves along the top planar surface and a first plate between the grooves. The top planar surface is then doped to form a conductor region including the first plate. A substantially uniform layer of a selectively etchable material, such as silicon oxide, is then grown over the grooved top planar surface. A layer of doped silicon is grown over the silicon oxide layer to define a pair of V-shaped members opposite the pair of grooves. The silicon layer is then partially etched to form a second plate connected to the silicon layer through a pair of V-shaped members. Both the second plate and the pair of V-shaped members are then suspended over the first capacitive plate by sacrificially etching a portion of the selectively etchable layer.

Abstract: A method of bonding two silicon wafers each having a capacitive plate. Two highly-doped electrically semiconductive feedthrough paths are formed through one wafer, each path contacting one of the capacitive plates. A glass layer is formed on one of the silicon wafers where bonding is desired between the two wafers. The glass layer is anodically bonded to the other of the silicon layers.

Abstract: A silicon variable capacitance pressure sensor has two silicon wafers. The first wafer has a first capacitor plate contacting a highly doped first semiconductor path through the first wafer. The second wafer has a second capacitor plate contacting a highly doped second semiconductor path through the second wafer. An insulating layer is attached to the first and second wafers for preventing electrically conductive coupling between the first and second wafers, thereby reducing parasitic capacitance between the first and second semiconductor paths.

Abstract: A method of forming a hermetic seal between two silicon wafers includes forming opposing troughs in each of the two wafers. In each trough are formed an isolation layer, a diffusion barrier and a tub of polysilicon. A gold strip is put on one polysilicon tub and the two silicon wafers are brought together and heated in a thermal gradient oven. A silicon gold eutectic is formed which migrates to the diffusion barrier of the silicon wafer.

Abstract: A capacitive pressure sensor uses two silicon wafers hermetically sealed to each other by recrystallized silicon formed by the migration of a ring of silicon-aluminum eutectic material from the wafer interface to the surface of one wafer. Within the ring of the eutectic a cavity with opposing conductive plates forms a capacitor. Another high conductivity path through the wafer can be formed simultaneously with the ring of eutectic material by placing an aluminum dot on the interior side of one silicon wafer. Thus, a high conductivity path is available through a silicon wafer for each of the two capacitor plates.

Abstract: This specification teaches a method of preparing an article which is electronically conductive and resistant to corrosive attack by molten polysulfide salts. The method is carried out by the following steps. A sheet of graphite foil is coated with an amorphous pyrolytic or glassy carbon to fill any openings in and/or through the graphite foil. A thin layer of aluminum metal is coated onto at least one side of the graphite foil. The aluminum metal coated side of the graphite foil is bonded to an aluminum surface of an electronically conductive material. In this manner, an electronically conductive article is formed which is resistant to corrosive attack by molten polysulfide salts.

Abstract: A method of providing a substrate with a layer of a tertiary compound comprising silicon, silicon carbide and a transition series metal. In accordance with the method, a substrate having at least a surface layer thereon of a transition series metal is coated with silicon carbide particles having an average particle diameter in the range of up to about two microns. The coated substrate is then heated in an inert atmosphere to a temperature between 1000.degree. and 1300.degree. C. for sufficient time to allow diffusion to occur between the silicon carbide and the transition series metal layer, thereby forming the tertiary compound. Substrates coated with the tertiary compound are particularly suitable for preparation of alkali metal/polysulfide batteries wherein the substrate may be exposed to corrosive attack by molten polysulfide salts.

Abstract: This disclosure is directed to an improvement in a sodium sulfur battery construction in which a seal between various battery compartments is made by a structure in which a soft metal seal member is held in a sealing position by holding structure. A pressure applying structure is used to apply pressure on the soft metal seal member when it is being held in sealing relationship to a surface of a container member of the sodium sulfur battery by the holding structure. The improvement comprises including a thin, well-adhered, soft metal layer on the surface of the container member of the sodium sulfur battery to which the soft metal seal member is to be bonded.

Abstract: In accordance with the teachings of this specification, a sodium sulfur battery is formed as follows. A plurality of box shaped sulfur electrodes are provided, the outer surfaces of which are defined by an electrolyte material. Each of the electrodes have length and width dimensions substantially greater than the thicknesses thereof as well as upwardly facing surface and a downwardly facing surface. An electrode structure is contained in each of the sulfur electrodes. A holding structure is provided for holding the plurality of sulfur electrodes in a stacked condition with the upwardly facing surface of one sulfur electrode in facing relationship to the downwardly facing surface of another sulfur electrode thereabove. A small thickness dimension separates each of the stacked electrodes thereby defining between each pair of sulfur electrodes a volume which receives the sodium reactant. A reservoir is provided for containing sodium.