Abstract: A cathode for electron emission, comprising a heating device (1, 2) for generating temperatures above 300° C., an electrically conductive cathode support (3) which is connected to the heating device (1, 2), and a cathode coating which is applied to the cathode support (3) and consists of an electron-emitting material (4) comprising at least one alkali metal selected from the group consisting of sodium, potassium, rubidium and cesium, with an emission current density >10 A/m2 at an operating temperature between 300° C. and 600° C.

Abstract: The present invention relates to a LED comprising a substrate, a first electrode layer and a thin colloidal layer located between the substrate and the first electrode layer, whereby the LED furthermore comprises a smoothening means located within or on the colloidal layer so that the roughness of the outer surface of the colloidal layer which is facing towards the first electrode layer is Ra?30 nm and Ra?1 nm.

Abstract: A gas discharge lamp, in particular a low-pressure gas discharge lamp, comprising an electrode including a carrier of an electrode metal and a first electrode coating of an electron-emitting material, which material comprises a metal powder preparation of a powder of a reducing metal selected from the group formed by aluminum, silicon, titanium, zirconium, hafnium, tantalum, molybdenum, tungsten and the alloys thereof, which metal powder preparation is provided with a powder coating containing a noble metal selected from the group formed by rhenium, cobalt, nickel, ruthenium, palladium, rhodium, iridium and platinum, and the alloys thereof, and said material comprising at least one alkaline earth metal oxide selected from the group formed by calcium oxide, strontium oxide and barium oxide, is characterized by a uniform emission current and a long service life.

Abstract: An electric discharge tube or discharge lamp comprising a scandate dispenser cathode which is composed of a cathode body and a coating having an emissive surface, said cathode body including a matrix of at least one refractory metal and/or a refractory alloy and a barium compound which is in contact with the matrix material to supply barium to the emissive surface by means of a chemical reaction with said matrix material, and the coating containing one or more multilayers which may include a bottom layer of tungsten and/or a tungsten alloy, an intermediate layer of rhenium and/or a rhenium alloy and a top layer of scandium oxide, a mixture of scandium oxide and rare-earth metal oxides, a scandate and/or a scandium alloy, is characterized by a long service life and a high emission-current density.

Abstract: A cathode having a matrix body (1) impregnated with an alkaline earth compound, whose surface is provided with a top coat (2, 3, 4) comprising a high melting point metal, such as particularly tungsten, and scandium. A high emission at a low operating temperature and simultaneously a rapid recuperation after ion bombardment as well as a long lifetime are achieved in that the top coat comprises at least two layers of different composition, with a purely metallic layer (5, 6, 7) being provided on the impregnated matrix body (1), which layer comprises scandium and a high melting point metal such as particularly tungsten and/or rhenium, and in that a metallic layer of a high melting point metal such as particularly tungsten is provided as a sealing layer.

Abstract: An electric discharge tube or discharge lamp, in particular a flat-panel display screen, includes one or more low-temperature cathodes having a holder, which, optionally, is provided with a heating or cooling element, a conductive bottom layer which is applied to the holder, optionally a substrate with dispenser material, and a top coating of ultrafine particles having a nanostructure. The top coating has a surface layer consisting of an emitter complex formed from an emission material comprising several components. The cathodes have a high reliability and a long service life under a normal working load. The emission is stable, which contributes to a constant picture quality throughout the life of the discharge lamp or discharge tube. The discharge tubes or discharge lamps in accordance with the invention have short switching times and the advantage that their construction has been simplified and that their energy consumption is low.

Abstract: The invention relates to a controllable thermionic electron emitter for vacuum tubes, which comprises an emitter layer (3, 27) and a control layer (5) which is separated from the emitter layer by an insulating layer (4), with the insulating layer and the control layer being manufactured by a deposition process. Also when its dimensions are small, such an electron emitter can be dimensionally accurately manufactured. All functional elements of the controllable thermionic electron emitter, more particularly control layer(s) (5, 7, 22, 24), emitter layer (3, 27) and separating insulating layers (2, 4, 6, 21, 23, 25) are successively deposited on a substrate (1, 20) in the direction of growth, in such a manner that the layers adhere to each other via solid boundary layers. In operation and, in particular, when the temperature varies, the dimensional accuracy of the electron emitter is preserved within narrow limits, and said electron emitter has a long service life.

Abstract: Uniform electrically conducting multicomponent material is deposited on an electrically conducting substrate by means of a PCVD method. A plasm, for example a glow discharge plasm, a high frequency plasm or a microwave plasm is generated in a reaction space. The plasma is periodically reciprocated. Starting materials for the single components of the multicomponent material are added to a flowing gas phase. To obtain multicomponent material of the desired composition, the flowing gas phase is split into at least two flowing gas phases each comprising only starting materials for a single component of the multicomponent material. The separate gas phases are time sequentially applied to the plasma. The deposited multicomponent material my be subjected to a thermal treatment.

Abstract: Cathode including a solid body (4) which comprises metallic constituents (particularly W, Ni, Mg, Re, Mo, Pt) and oxidic constituents (such as particularly BaO, CaO, Al.sub.2 O.sub.3, Sc.sub.2 O.sub.3, SrO, ThO.sub.2, La.sub.2 O.sub.3).Also at low operating temperatures, high emission current densities and a long lifetime are achieved in that the structure of the constituents and the volume ratio v.sub.m of the metallic constituents relative to the overall volume of the solid body are chosen to be such that the resistivity .rho. has a value in the range of .rho..sub.0 .multidot.10.sup.-4 >.rho.>.rho..sub.m .multidot.10.sup.2, in which .rho..sub.0 and .rho..sub.m are the resistivities, defined at 20.degree. C., of the pure oxidic constituents and the pure metallic constituents, respectively.

Abstract: Uniform electrically conducting multicomponent material is deposited on an electrically conducting substrate by means of a PCVD method. A plasma, for example a glow discharge plasma, a high frequency plasma or a microwave plasma is generated in a reaction space. The plasma is periodically reciprocated. Starting materials for the single components of the multicomponent material are added to a flowing gas phase. To obtain multicomponent material of the desired composition, the flowing gas phase is split into at least two flowing gas phases each comprising only starting materials for a single component of the multicomponent material. The separate gas phases are time sequentially applied to the plasma. The deposited multicomponent material may be subjected to a thermal treatment.

Abstract: A method of manufacturing a hot-cathode element which consists of a rare-earth-oxide-doped refractory metal, notably thoriated tungsten, and which also contains carbon components, first a plurality of layers of the hot-cathode element being successively deposited on a substrate member (2) by means of a CVD process, after which notably the hot-cathode element is separated from the substrate member (2). The strength required for further working of the hot-cathode element is improved in that in the course of the CVD process decarburizing intermediate treatments are performed, the hot-cathode element being carburized during an aftertreatment.

Abstract: Ultrafine particles (9) are produced from a target 30) by laser beam evaporation. The laser beam (1) is directed to the target in such a manner that the removal of the target material takes place in the direction of movement of the laser beam. The ultrafine particles thus manufactured are preferably used for the manufacture of single or multi-component materials or moulded bodies from such materials; by coating substrates (15) with said ultrafine particles.

Abstract: The microwave transmission between wave guide regions (a, b) having different internal gas pressures and/or different fill-gas compositions, that is to say, the coupling or outcoupling of microwaves of such a wave guide region into another region is improved in that between the wave guide regions at least a single pumping stage (6, 7, 8, 9) is inserted. The wave guide (1) is connected to the pumping stages preferably via the slots (2, 3, 4, 5) which do not virtually outcouple the microwave power.

Abstract: An arrangement for producing a gas flow which is enriched with the vapor of a low-volatile material. The arrangement comprises a vessel (1) having an interior space (12) for holding a powder bed (13), which consists of a low-volatile material and an additional solid inert component. The vessel is arranged in a thermostatically controlled bath (2). A gas flow (4, 16) consisting of an inert gas flows through the arrangement, preferably in the direction of the gravitational force. The gas flow passes, in this sequence, through a thick gas inlet plate (10), the powder bed (13) and a thin gas outlet plate (14). By proper dimensioning the component parts of the arrangement and providing a low pressure in the arrangement a high mass flow of the low-volatile material with a flow constant of a long duration is achieved. The enriched gas flow is conducted, for example, to a low-pressure CVD reactor.

Abstract: The cathode (4) the material of which is substantially high-melting metal such as W, Mo, Ta, Nb, Re and/or C, consists of a very fine-grained mechanically stable support layer (5), a series of layers (6) considerably enriched with emissive material, in general from the scandium group especially from the group of rare earth metals, preferably with Th or compounds thereof and a thermally stable preferentially oriented coating layer (7). All the layers are provided via the gaseous phase, for example, CVD methods, on a substrate (1) formed according to the desired cathode geometry. The substrate (1) is removed after termination of the deposition. FIG. 2.

Abstract: A borided dispenser cathode of the type including a metallic base material is made by cleaning the cathode by annealing it in a hydrogen-containing atmosphere, depositing boron on the cathode by heating the cathode in an atmosphere containing a gaseous boron compound, and forming a boride of the metallic base material by heating the cathode to its operating temperature in a non-reactive atmosphere and maintaining the temperature for a time period sufficient to enable deposited boron to combine with the metallic base material.

Abstract: A cathode having a layer structure in which alternate layers consisting essentially of emitter material (2) and base material (1) are provided at an oblique angle to the cathodes's macroscopic emitting surface. In a preferred embodiment the surface has a microscopically stepped structure formed by ends of the base material layers and portions of the emitter material layers coating the ends. In an alternative embodiment the surface is not stepped but is formed by a polycrystalline or a preferentially oriented polycrystalline coating layer which is provided on the succession of beveled layers. The succession of layers is manufactured by alternating depositions from the gaseous phase and by subsequent bevel grinding of the layers. The polycrystalline coating layer is provided by deposition from the gaseous phase. The stepped surface is formed, for example, by selective structure etching after the bevel grind.