Abstract:
The present invention pertains to the use of quasione-dimensional transition metal ternary compounds MXHyHaZ (where M is a transition metal Mo, W, Ta, Nb; H is sulfur (S), selenium (Se), tellurium (Te); Ha is iodine (I)) and of doped quasi-one-dimensional transition metal ternary compounds MXHyHaZ, (where M=Ta, Ti, Nb; H is sulfur (S), selenium (Se), tellurium (Te); Ha is iodine (I)) with elements of group lb (silver (Ag), gold (Au), or copper (Cu)) as electron emitters under the influence of an external electric field. The percentage of quasi-onedimensional transition metal ternary compounds and/or doped quasi-one-dimensional transition metal ternary compounds doped with elements of group lb in the active material ranges from 0.01 to 99.9 the rest consisting of additives in the form of conducting, non-conducting or semi-conducting compounds or composites. Electron emission takes place at a pressure below 1 mbar.
Abstract:
Annealed carbon soot is useful as an electron field emitter. Field emitting cathodes made up of annealed carbon soot attached to the surface of a substrate are also provided. The field emitters and field emitter cathodes are useful in vacuum electronic devices, flat panel computer and television displays, emission gate amplifiers, klystrons and lighting devices.
Abstract:
A method for preparing single-crystalline, rare-earth metal hexaboride nanowires by a chemical vapor deposition process is described. Also described are the nanowires themselves, the electron emitting properties of the nanowires, and the use of the nanowires in electron emitting devices, particularly as point electron sources.
Abstract:
There is disclosed an improved field emission device (30) which finds use in display devices, such as a flat panel displays. Known devices and displays suffer from problems such as complexity of fabrication and limited colour gamut. The device (30) therefore provides a field emission backplate (38) which is made from a substantially semiconductor based material and comprises a plurality of grown tips (32), the device (30) further comprising at least one electro-luminescent and/or photo-luminescent material (34) having a fluorescent material chemically attached thereto, i.e. a fluorescent dye doped material.
Abstract:
A field emission cold cathode (11) for use in vacuum tubes. A carbon velvet material (25) is comprised of high aspect ratio carbon fibers embedded perpendicular to a base material. The tips and/or the shafts of the carbon velvet material (25) are coated with a low work function cesiated salt. The base material of the carbon velvet material (25) is bonded to a cathode surface (27). The cold cathode (11) emits electrons when an electric field is applied, even at operating temperatures less than 900°C.
Abstract:
There is disclosed an improved field emission device (30) which finds use in display devices, such as a flat panel displays. Known devices and displays suffer from problems such as complexity of fabrication and limited colour gamut. The device (30) therefore provides a field emission backplate (38) which is made from a substantially semiconductor based material and comprises a plurality of grown tips (32), the device (30) further comprising at least one electro-luminescent and/or photo-luminescent material (34) having a fluorescent material chemically attached thereto, i.e. a fluorescent dye doped material.
Abstract:
An electron field emission device is provided by placing a substrate in a reactor, heating the substrate and supplying a mixture of hydrogen and a carbon-containing gas at a concentration of about 8 to 13 per cent to the reactor while supplying energy to the mixture of gases near the substrate for a time to grow a first layer of carbon-based material to a thickness greater than about 0.5 micrometers, subsequently reducing the concentration of the carbon-containing gas and continuing to grow a second layer of carbon-based material, the second layer being much thicker than the first layer. The substrate is subsequently removed from the first layer and an electrode is applied to the second layer. The device is free-standing and can be used as a cold cathode in a variety of electronic devices such as cathode ray tubes, amplifiers and traveling wave tubes. The surface of the substrate may be patterned before growth of the first layer to produce a patterned surface on the field emission device.