Abstract:
An optoelectronic modulator is based on the concentration of an electron beam from an electron gun by a tapered cavity, which sides are photosensitive and change the electrical conductivity under the illumination of light (electromagnetic radiation). The light modulation causes the corresponding changes in the current transported across the walls of the cavity. The remaining part of the electron current exits the cavity aperture and forms an amplitude-modulated divergent electron beam.
Abstract:
A cold cathode is formed of n-type boron nitride. The cathode may include a layer of diamond underlying the boron nitride. The cathodes are made by laser ablation or by sputtering. Electronic devices utilizing the boron nitride cathodes are also described.
Abstract:
A lateral-emitter field emission device has a thin-film emitter cathode 50 which has thickness of not more than several hundred angstroms and has an edge or tip 110 having a small radius of curvature. To form a novel display cell structure, a cathodoluminescent phosphor anode 60 is positioned below the plane of the thin-film lateral-emitter cathode 50, allowing a large portion of the phosphor anode's top surface to emit light in the desired direction. An anode contact layer contacts the phosphor anode 60 from below to form a buried anode contact 90 which does not interfere with light emission. The anode phosphor is precisely spaced apart from the cathode edge or tip and receives electrons emitted by field emission from the edge or tip of the lateral-emitter cathode, when a small bias voltage is applied. The device may be configured as a diode, triode, or tetrode, etc. having one or more control electrodes 140 and/or 170 positioned to allow control of current from the emitter to the phosphor anode by an electrical signal applied to the control electrode. In a particularly simple embodiment, a single control electrode 140 is positioned in a plane below the emitter edge or tip 110 and automatically aligned to that edge. The display cell structure may be repeated many times in an array, and the display cell structure of the invention lends itself to novel array structures which are also disclosed. A fabrication process is disclosed using subprocess steps S1-S19 similar to those of semiconductor integrated circuit fabrication to produce the novel display cell structures and their arrays. Various embodiments of the fabrication process allow the use of conductive or insulating substrates 20 and allow fabrication of devices having various functions and complexity.
Abstract:
A vacuum integrated electronic device has an anode region of conductive material; an insulating region on top of the anode region; a cavity extending through the insulating region and having a sidewall; and a cathode region. The cathode region has a tip portion extending peripherally within the cavity, adjacent to the sidewall of the cavity. The cathode region is formed by tilted deposition, carried out at an angle of 30-60° with respect to a perpendicular to the surface of device.
Abstract:
The present disclosure includes field emission device embodiments. The present disclosure also includes method embodiments for forming field emitting devices. One device embodiment includes a housing defining an interior space including a lower portion and an upper portion, a cathode positioned in the lower portion of the housing, a elongate nanostructure coupled to the cathode, an anode positioned in the upper portion of the housing, and a control grid positioned between the elongate nanostructure and the anode to control electron flow between the anode and the elongate nanostructure.
Abstract:
New, hybrid vacuum electron devices are proposed, in which the electrons are extracted from the nanotube into vacuum. Each nanotube is either placed on the cathode electrode individually or grown normally to the cathode plane. Arrays of the nanotubes are also considered to multiply the output current. Two- and three-terminal device configurations are discussed. In all the cases considered, the device designs are such that both input and output capacitances are extremely low, while the efficiency of the electron extraction into vacuum is very high, so that the estimated operational frequencies are expected to be in a tera-hertz range. New vacuum triode structure with ballistic electron propagation along the nanotube is also considered.
Abstract:
Methods for making low work function electrodes either made from or coated with an electride material in which the electride material has lattice defect sites are described. Lattice defect sites are regions of the crystal structure where irregularities and deformations occur. Also provided are methods for making electrodes which consist of a substrate coated with a layer of a compound comprised of a cation complexed by an electride former, in which said complex has lattice defect sites. In addition, methods for making electrodes which consist of a bulk metal coated with a layer of an electride former having lattice defect sites are described. The electride former stabilizes the loss of electrons by surface sites on the metal, lowering the work-function of the coated surface.
Abstract:
A lateral-emitter field emission device has a thin-film emitter cathode 50 which has thickness of not more than several hundred angstroms and has an edge or tip 110 having a small radius of curvature. To form a novel display cell structure, a cathodoluminescent phosphor anode 60 is positioned below the plane of the thin-film lateral-emitter cathode 50, allowing a large portion of the phosphor anode's top surface to emit light in the desired direction. An anode contact layer contacts the phosphor anode 60 from below to form a buried anode contact 90 which does not interfere with light emission. The anode phosphor is precisely spaced apart from the cathode edge or tip and receives electrons emitted by field emission from the edge or tip of the lateral-emitter cathode, when a small bias voltage is applied. The device may be configured as a diode, triode, or tetrode, etc. having one or more control electrodes 140 and/or 170 positioned to allow control of current from the emitter to the phosphor anode by an electrical signal applied to the control electrode. In a particularly simple embodiment, a single control electrode 140 is positioned in a plane below the emitter edge or tip 110 and automatically aligned to that edge. The display cell structure may be repeated many times in an array, and the display cell structure of the invention lends itself to novel array structures which are also disclosed. A fabrication process is disclosed using subprocess steps S1-S19 similar to those of semiconductor integrated circuit fabrication to produce the novel display cell structures and their arrays. Various embodiments of the fabrication process allow the use of conductive or insulating substrates 20 and allow fabrication of devices having various functions and complexity.
Abstract:
A novel use of doped carbonaceous material is disclosed, integral to the operation of Vacuum Diode Heat Pumps and Vacuum Diode Thermionic Generators. In the preferred embodiment, the use of nitrogen-doped diamond enhances the operation of Vacuum Diode Heat Pumps and Vacuum Diode Thermionic Generators.
Abstract:
Electronic device comprising an evacuated envelope containing a main thermionic cathode heated solely by energetic electrons emitted from an unheated auxiliary field-emission cathode.