Abstract:
Die Erfindung betrifft eine Vorrichtung zur Erzeugung von Röntgenstrahlung in einem äußeren Magnetfeld (50), das durch eine Magnetfeldeinrichtung erzeugbar ist. Die Vorrichtung (1) umfasst eine Kathode (10) zur Erzeugung eines Elektronen- strahls (30) sowie eine Anode (20) zum Abbremsen der Elektronen des Elektronenstrahls (30) und zum Erzeugen eines Röntgenstrahls (50). Ferner umfasst die Vorrichtung (1) eine Einrichtung zum Erzeugen eines von der Anode (20) in Richtung der Kathode (10) gerichteten und zu dem äußeren Magnetfeld (50) im Wesentlichen kollinearen elektrischen Felds, wobei die Kathode (10) als Elektronenemitter (12) eine Kaltkathode umfasst, welche passiv mittels Feldemission freie Elektronen bereitstellt.
Abstract:
A vacuum encapsulated, hermetically sealed cathode capsule for generating an electron beam of secondary electrons, which generally includes a cathode element having a primary emission surface adapted to emit primary electrons, an annular insulating spacer, a diamond window element comprising a diamond material and having a secondary emission surface adapted to emit secondary electrons in response to primary electrons impinging on the diamond window element, a first cold- weld ring disposed between the cathode element and the annular insulating spacer and a second cold- weld ring disposed between the annular insulating spacer and the diamond window element. The cathode capsule is formed by a vacuum cold- weld process such that the first cold-weld ring forms a hermetical seal between the cathode element and the annular insulating spacer and the second cold- weld ring forms a hermetical seal between the annular spacer and the diamond window element whereby a vacuum encapsulated chamber is formed within the capsule.
Abstract:
Vacuum microelectronic devices with carbon nanotube films, layers, ribbons and fabrics are provided. The present invention discloses microelectronic vacuum devices including triode structures that include three-terminals (an emitter, a grid and an anode), and also higher-order devices such as tetrodes and pentodes, all of which use carbon nanotubes to form various components of the devices. In certain embodiments, patterned portions of nanotube fabric may be used as grid/gate components, conductive traces, etc. Nanotube fabrics may be suspended or conformally disposed. In certain embodiments, methods for stiffening a nanotube fabric layer are used. Various methods for applying, selectively removing (e.g. etching), suspending, and stiffening vertically- and horizontally- disposed nanotube fabrics are disclosed, as are CMOS -compatible fabrication methods. In certain embodiments, nanotube fabric triodes provide high-speed, small-scale, low -power devices that can be employed in radiation-intensive applications.