166 results about "Thermionic emission" patented technology

Impact on parametric performance of physical design choices for transistors is scored for on-current and off-current of the transistors. The impact of the design parameters are incorporated into parameters that measure predicted shift in mean on-current and mean off-current and parameters that measure predicted increase in deviations in the distribution of on-current and the off-current. Statistics may be taken at a cell level, a block level, or a chip level to optimize a chip design in a design phase, or to predict changes in parametric yield during manufacturing or after a depressed parametric yield is observed. Further, parametric yield and current level may be predicted region by region and compared with observed thermal emission to pinpoint any anomaly region in a chip to facilitate detection and correction in any mistakes in chip design.

A thermionic emission device includes an insulating substrate, and one or more grids located thereon. Each grid includes a first, second, third and fourth electrode down-leads located on the periphery thereof, and a thermionic electron emission unit therein. The first and second electrode down-leads are parallel to each other. The third and fourth electrode down-leads are parallel to each other. The first and second electrode down-leads are insulated from the third and fourth electrode down-leads. The thermionic electron emission unit includes a first electrode, a second electrode, and a thermionic electron emitter. The first electrode and the second electrode are separately located and electrically connected to the first electrode down-lead and the third electrode down-lead respectively. The insulating substrate comprises one or more recesses that further insulate the thermionic electron emitters from the substrate.

A novel x-ray treatment system utilizes one or more large area flat panel sources of x-ray radiation directed into a target zone. A target substance within the target zone is irradiated with x-ray radiation from the one or more flat panel sources, reducing the biological effects of a contaminant presence therein. The flat panel source comprises an electron source, an electron accelerator, and an electron target medium. The electron source may emit electrons either via field emission or thermionic emission. The x-ray source may operate in transmissive, reflective, or combined transmissive/reflective mode. The use of large area flat panel x-ray sources in the inventive systems allows for decreased installation and operational costs as well as increased efficiency.

A fast and rigorous multivariate curve resolution (MCR) algorithm is applied to remotely sensed spectral data. The algorithm is applicable in the solar-reflective spectral region, comprising the visible to the shortwave infrared (ranging from approximately 0.4 to 2.5 μm), midwave infrared, and thermal emission spectral region, comprising the thermal infrared (ranging from approximately 8 to 15 μm). For example, employing minimal a priori knowledge, notably non-negativity constraints on the extracted endmember profiles and a constant abundance constraint for the atmospheric upwelling component, MCR can be used to successfully compensate thermal infrared hyperspectral images for atmospheric upwelling and, thereby, transmittance effects. Further, MCR can accurately estimate the relative spectral absorption coefficients and thermal contrast distribution of a gas plume component near the minimum detectable quantity.

An optical device for generating narrow-band circularly and elliptically polarized radiation, either by conversion from externally incident light or through thermal emission of heated objects. The optical device includes a metasurface comprised of unit cells, where each unit cell contains structural elements or features that break two mirror inversion symmetries of the unit cell and couple bright and dark resonances. In this manner, the optical device emits circularly polarized radiation that does not exhibit a preference for right-hand circularly polarized light or left-hand circularly polarized light incident upon it. As a result, multiple of such optical devices with different unit cell sizes, geometries and dimensions of the intra-cell elements may be implemented as a tag that thermally emits different states of circularly polarized radiation confined to multiple spectrally-narrow bands. Since the optical device can be fabricated in CMOS, the tag can be used for preventing/identifying tampering with genuine electronic components.

The present invention relates to a device for improving plasma activity in a magnetron sputtering reactor containing substrates to be coated where a primary plasma is created by a DC or AC voltage applied between the substrates and an additional electrode. Increased plasma activity is obtained by thermionic emission of electrons from a hot filament heated by either DC or AC current or combinations thereof. The device is particularly useful for increasing the adhesion of layers deposited by magnetron sputtering on cutting tool inserts made of cemented carbide, high speed steels, cermets, ceramics or cubic boron nitride.

Band-edge aligned carrier blocking layers are introduced into wurtzite or zinc blende Gallium Nitride based diode laser and LEDs in order to prevent thermionic emission and the overflow of carriers at elevated operating temperatures. These blocking layers are located in the direct vicinity of the active zone of the light emitter, and are designed with material composition such that one of the band-edges of the layers is, either partially or fully, aligned with that of adjacent barrier or waveguide layer. This invention proposes GaN based QW structure with a AlGaN(AsPSb) electron-blocking layer on the p-side of quantum well and (InGa)AlN as hole-blocking layer.

The present disclosure relates to a patterned surface composite structure. The structure includes a first material having a specific coefficient-of-thermal-expansion and a second material having a different coefficient-of-thermal-expansion. The first material can be patterned with specific features and the second material may be located between those features, thereby forming areas having a coefficient-of-thermal-expansion between that of the first and second materials. A thermally emissive device, such as a laser diode, may be attached to a surface of the patterned composite structure.

An electron beam system wherein a shot noise of an electron beam can be reduced and a beam current can be made higher, and further a shaped beam is formed by a two-stage lenses so as to allow for an operation with high stability. In this electron beam system, an electron beam emitted from an electron gun is irradiated onto a sample and secondary electrons emanated from the sample are detected. The electron gun is a thermionic emission type and designed to operate in a space charge limited condition. A shaping aperture and a NA aperture are arranged in front locations of the electron gun. An image of the shaping aperture formed by an electron beam emitted from the thermionic emission electron gun is focused onto a surface of the sample through the two-stage lenses.

A vapor deposition coating system including a metal vapor source, a power supply coupled to the metal vapor source, at least one thermionic ionizing grid including one or more thermionic filaments, wherein the ionizing grid is at least partially located within a region having a metal atom flow density in the range of 1E14m⁻³ to 1E24m³ when the power supply coupled to the metal vapor source is energized; and a heating power supply coupled to the thermionic ionizing grid, wherein the heating power supply is configured to heat the filaments to the thermionic emission temperature of the filaments. The thermionic discharge is energized between the thermionic ionizing grid connected to the negative pole of power supply as a cathode and the anode connected to the positive pole of the power supply.

An optical scanning apparatus including a laser diode light source fittingly inserted into a holding member. The holding member is formed of a resin material having a thermal conductivity of 0.7 w/m°K or more and filled with either glass fiber or metal oxide or both, or aluminum. A heat radiating fin projecting radially is formed on an outer circumferential portion of the cylindrical body of the holding member. With this structure, temperature rise due to heat emission from the laser diode can be suppressed and deterioration of the laser diode can be prevented. This structure simply and inexpensively provides stable optical properties to optical scanning and image forming devices.

The invention discloses a selective-radiation infrared stealth structure, and relates to the technical field of infrared stealth. The infrared stealth structure comprises a plurality of infrared selective heat emission units which are arranged and distributed in the form of a matrix according to a period p; each infrared selective heat emission unit comprises a substrate layer, a metal backboard, a dielectric layer and a metal sheet layer which are sequentially arranged from bottom to top; each metal sheet layer comprises a first metal sheet, a second metal sheet, a third metal sheet and a fourth metal sheet; and the first metal sheets, the second metal sheets, the third metal sheets and the fourth metal sheets are arranged on the dielectric layers by spacing by 90 degrees around the centers of the infrared selective heat emission units. The selective-radiation infrared stealth structure disclosed by the invention realizes selective thermal radiation through electromagnetic resonance characteristics of an infrared metamaterial, and realizes an infrared stealth technology through the transmitted spectrum design.

A device or class of devices that provides a mechanism for controlling charge current flow in transistors that employs collective magnetic effects to overcome voltage limitations associated with single-particle thermionic emission as in conventional MOSFETs. Such a device may include two or more magnetic stacks with an easy-in-plane ferromagnetic film sandwiched between oppositely magnetically oriented perpendicular magnetization anisotropy (PMA) ferromagnets. Each stack includes two non-magnetic layers separating the easy-plane ferromagnetic film from the PMA layers. Charge current flow through one of these stacks controls the current-voltage negative differential resistance characteristics of the second stack through collective magnetic interactions. This can be exploited in a variety of digital logic gates consuming less energy than conventional CMOS integrated circuits. Furthermore, the easy-in-plane magnetic films may be subdivided into regions coupled through exchange interactions and the in-plane fixed magnetic layers in the input magnetic stacks can be used in non-volatile logic and memory.

The electron emission portion of a cathode for an electron gun has layers of substrate material formed from a ceramic powder such as Aluminum nitride. The substrate layers have conductive traces formed on them, the conductive traces made from sintered tungsten or alternatively a refractory foil. When current is passed through the conductive traces, heat is coupled to a cathode which is thermally coupled to the heater assembly. In another embodiment of the invention, one of the layers of the heater includes a thermionic emission material and optionally a work function lowering material such as BaO, which allows the outer layer of the multi-layer heater to directly emit electrons. In another embodiment of the invention, a control grid is formed on a layer above the thermionic cathode layer, which provides for a complete electron gun assembly having a heater, cathode with a reduced work function material, and control grid to be fabricated as a single unit at the same time.

A miniaturized, optically driven therapeutic radiation source (100) includes a laser-heated thermionic cathode (122). A fiber optic cable (113) directs a light beam from an optical source (104) to impinge upon a surface of the thermionic cathode (122), heating the surface to a temperature sufficient to cause thermionic emission of electrons. The target element (128) emits therapeutic radiation, such as x-rays, in response to incident accelerated electrons from the electron beam. In one embodiment, the electron source (122) and the target element (128) are disposed within a capsule (130) which defines a substantially evacuated region. The inner surface of the capsule is coated with a semiconductor coating, so that a uniform voltage gradient is maintained within the evacuated capsule. In another embodiment, the thermionic cathode (300) is formed of a spiral-shaped conductive element (310) having a plurality of spaced-apart turns. Interstitial spacing between adjacent turns essentially eliminates heat transfer across the spacin.

A solar generator can include a photon-enhanced thermionic emission generator with a cathode to receive solar radiation. The photon-enhanced thermionic emission generator can include an anode that in conjunction with the cathode generates a first current and waste heat from the solar radiation. A thermoelectric generator can be thermally coupled to the anode and can convert the waste heat from the anode into a second current. A circuit can connect to the photon-enhanced thermionic emission generator and to the thermoelectric generator and can combine the first and the second currents into an output current.

A quantum dot (QD) laser having greatly reduced temperature sensitivity employs resonant tunnel-injection of carriers into the QDs from a pair of quantum wells (QWs). The carriers are injected through barrier layers. Because the tunnel-injection process is essentially temperature-independent, and because the tunnel-injection of carriers is the dominant source of current through the device, temperature-dependent currents are virtually eliminated, resulting in a device having a temperature-independent threshold current. In an additional device, carriers are injected into QDs from a pair of optical confinement layers (OCLs), either by tunnelling or thermionic emission. Each barrier layer is designed to have a low barrier height for carriers entering the QDs, and a high barrier height for carriers exiting the QDs. As a result, parasitic current from carriers leaving the QDs is greatly reduced, which enables the device to have low temperature sensitivity even without using resonant tunnel-injection and/or QWs.

A thermionic emission device includes an insulating substrate, and one or more grids located thereon. Each grid includes a first, second, third and fourth electrode down-leads located on the periphery thereof, and a thermionic electron emission unit therein. The first and second electrode down-leads are parallel to each other. The third and fourth electrode down-leads are parallel to each other. The first and second electrode down-leads are insulated from the third and fourth electrode down-leads. The thermionic electron emission unit includes a first electrode, a second electrode, and a thermionic electron emitter. The first electrode and the second electrode are separately located and electrically connected to the first electrode down-lead and the third electrode down-lead respectively. The thermionic electron emitter includes at least one carbon nanotube wire.