Abstract:
The present invention provides for a field emission device including an anode assembly and a cathode assembly, wherein the cathode assembly further includes a substrate, a plurality of electrically conducting strips deposited on the substrate, and a continuous layer of diamond material deposited over the plurality of electrically conducting strips and portions of the substrate exposed between the plurality of electrically conducting strips. The field emission device may further include a grid assembly including a perforated silicon substrate, a first dielectric layer deposited on the silicon substrate, and a first conducting layer deposited on the first dielectric layer, wherein the first dielectric layer and the first conducting layer have perforations coinciding with perforations of the silicon substrate. The grid assembly may further include a second dielectric layer deposited on an underside of the silicon substrate, wherein the second dielectric layer has perforations coinciding with perforations of the silicon substrate.
Abstract:
A field emitter including an exposed wide band gap emission area in contact with and protruding from a planar surface of a conductive metal, and a method of making is disclosed. Suitable wide band gap materials (2.5-7.0 electron-volts) include diamond, aluminum-nitride and gallium-nitride; suitable conductive metals include titanium, tungsten, gold and graphite. The method includes disposing the wide band gap material on a substrate, disposing the conductive metal on the wide band gap material, and etching the conductive metal to expose wide band gap emission areas. The emission areas are well suited for large area flat panel displays.
Abstract:
A field-emission structure suitable for large-area flat-panel televisions centers around an insulating porous layer that overlies a lower conductive region situated over insulating material of a supporting substrate. Electron-emissive filaments occupy pores extending through the porous layer. A conductive gate layer through which openings extend at locations centered on the filaments typically overlies the porous layer. Cavities are usually provided in the porous layer along its upper surface at locations likewise centered on the filaments.
Abstract:
Concave portions are formed, in a matrix fashion, in a substrate formed of metal or semiconductor. An electron emission layer made of material having small work function such as a diamond thin film is formed on the bottom portion of the concave portion. A protruding portion of the substrate serves as a beam formation electrode. Divergence of electrons can be suppressed with the beam formation electrode. A gate electrode for drawing out the electrons is formed above the beam formation electrode.
Abstract:
In accordance with the invention, a field emission device is made by disposing emitter material on an insulating substrate, applying masking particles to the emitter material, applying an insulating film and a gate conductor film over the masking particles and emitter material and removing the particles to reveal a random distribution of apertures to the emitter material. The result is a novel and economical field emission device having numerous randomly distributed emission apertures which can be used to make low cost flat panel displays.
Abstract:
A field emission display having a diamond thin film having a low work function due to its affinity for electrons used for forming a micro-tip. Electron emitting micro-tips are manufactured using diamond or diamond-like carbon which have a low work function due to their affinity for electrons, and thereby facilitate electron emission at a very low gate voltage. Manufacturing a flat micro-tip allows uniform tips to be formed so that a large device can be easily fabricated.
Abstract:
Improved field-emission devices are based on composing the back contact to the emitter material such that electron-injection efficiency into the emitter material is enhanced. Alteration of the emitter material structure near the contact or geometric field enhancement due to contact morphology gives rise to the improved injection efficiency. The devices are able to emit electrons at high current density and lower applied potential differences and temperatures than previously achieved. Wide-bandgap emitter materials without shallow donors benefit from this approach. The emission characteristics of diamond substitutionally doped with nitrogen, having a favorable emitter/vacuum band structure but being limited by the efficiency of electron injection into it, show especial improvement in the context of the invention. The injection-enhancing contacts can be created by combining the emitter material with an appropriate metal compound and annealing or by conventional dry anisotropic etching or ion bombardment techniques.
Abstract:
In accordance with the invention, a field emission device is made by disposing emitter material on an insulating substrate, applying a sacrificial film to the emitter material and forming over the sacrificial layer a conductive gate layer having a random distribution of apertures therein. In the preferred process, the gate is formed by applying masking particles to the sacrificial film, applying a conductive film over the masking particles and the sacrificial film and then removing the masking particles to reveal a random distribution of apertures. The sacrificial film is then removed. The apertures then extend to the emitter material. In a preferred embodiment, the sacrificial film contains dielectric spacer particles which remain after the film is removed to separate the emitter from the gate. The result is a novel and economical field emission device having numerous randomly distributed emission apertures which can be used to make low cost flat panel displays.
Abstract:
A matrix addressable flat panel display includes a flat cathode operable for emitting electrons to an anode when an electric field is produced across the surface of the flat cathode by two electrodes placed on each side of the flat cathode. The flat cathode may consist of a cermet or amorphic diamond or some other combination of a conducting material and an insulating material such as a low effective work function material. The electric field produced causes electrons to hop on the surface of the cathode at the conducting-insulating interfaces. An electric field produced between the anode and the cathode causes these electrons to bombard a phosphor layer on the anode.
Abstract:
A field emission cathode for use in flat panel displays is disclosed comprising a layer of conductive material and a layer of amorphic diamond film, functioning as a low effective work-function material, deposited over the conductive material to form emission sites. The emission sites each contain at least two sub-regions having differing electron affinities. Use of the cathode to form a computer screen is also disclosed along with the use of the cathode to form a fluorescent light source.