Abstract:
A cold cathode field emission device is described. A key feature of its design is that groups of microtips share a single conductive disk with a reliable ballast resistor being interposed between each of these conductive disks and the cathode conductor. Additionally, a resistor, rather than a conductor, is used to connect the gate conductive disk to the gate electrode. The latter is arranged so as not to overlap with the cathode electrode. The cathode and gate conductive disks ensure that the ballast resistance asociated with each microtip is essentially the same.
Abstract:
A field emission device has a basic substrate whose surface is coated with a conductive layer that forms an electrode. A field emission emitter which is formed as a micro-tip, is electrically connected to the electrode. Between the micro-tip and the electrode, a current limiting resistive silicon film is arranged and the resistivity of the silicon film is adjusted to be in a value ranging from about 10.sup.2 to about 10.sup.5 .OMEGA.cm by an n- or p-dopant. The silicon film contains an alloying element which would be able to form a silicon ceramic if used in a stoichiometric amount but would not be able to dope the silicon.
Abstract:
The invention generally relates to the technical field of devices using the effect to emit electrons out of a solid into vacuum due to high electric field strength. Such devices are usually called field emission devices. The invention relates more specifically to the structure of a field emission device, to the method of fabricating a field emission device, and to the use of a multitude of field emission devices in the technical field of flat panel displays. The inventive structure of a field emission device (15) comprises an individual series resistor for each electron emitting tip (1), wherein the series resistor is formed by the tip (1) itself. The tip (1) comprises a body (9) of a first material with high resistivity and an at least partial coating (7) of a second material with low work function, wherein the body (9) of the first material forms the series resistor and the coating (7) of the second material provides for electron emission. The method for fabricating a field emission device (15) uses depositing and sacrificial layer etch back techniques to provide easy and precise control of tip height and shape and also easy and precise control of the tip-to-gate distance and geometry.
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:
In a field emission cold cathode composed of a plurality of micro cold cathodes, the diameter of a plurality of openings formed in a gate electrode is large at a central region of an electron emission zone but small at a peripheral region of the electron emission zone, or the thickness of the gate electrode is small at the central region of the electron emission zone but large at the peripheral region of the electron emission zone. Alternatively, the thickness of an insulator layer is small at the central region of the electron emission zone but large at the peripheral region of the electron emission zone. Or, a resistance layer is provided between a substrate and a plurality of electron emission electrodes, and resistivity of the resistance layer is small at the central region of the electron emission zone but large at the peripheral region of the electron emission zone.
Abstract:
The present invention provides an emitter structure of a field emission electron gun. The emitter structure comprises an emitter being electrically conductive and being pointed at the top, wherein the top of the emitter has the highest resistance of every other part, so that the top of the emitter has the highest heat energy of every other part when the emitter emits electrons.
Abstract:
A field emitter structure, comprising: a base substrate; a field emitter element on the base substrate; a multilayer differentially etched dielectric stack circumscribingly surrounding the field emitter element on the base substrate; and a gate electrode overlying the multilayer differentially etched dielectric stack, and in circumscribing spaced relationship to the field emitter element. Also disclosed are electron source devices, comprising an electron emitter element including a material selected from the group consisting of leaky dielectric materials, and leaky insulator materials, as well as electron source devices, comprising an electron emitter element including an insulator material doped with a tunneling electron emission enhancingly effective amount of a dopant species, and thin film triode devices.
Abstract:
This disclosure is directed toward field emission surfaces, and is more particularly directed toward improvements in cold, low field, high current, low noise field emission devices and surfaces. Such devices are used in field emission display devices such as video displays and information displays. The device utilizes a cermet with graded concentration of insulative and conductive particles deposited on the truncated point of a conical emitter. The emission surface of the cermet is insensitive to gases that oxidize or poison the emission surface. Such gases and other contaminants emanate from a phosphor when the emission device is used in phosphor display devices. The field emission device is operated at lower potentials thereby reducing power requirements and minimizing heat dissipation requirements. Further, the field emission device which operates at lower field in order to reduce mechanically and temporally unstable emission sites which result in current bursts and current deficits at these sites. Still further, the field emission device incorporates internal resistors which provide series resistance to limit noise at affected emission areas thereby eliminating the need to limit noise by incorporating high-valued resistors, typically in series with the cathode terminal of the emission device, which reduce the potential to the entire emission surface and increasing potentials required to produce current sufficient to excite display phosphor.
Abstract:
A display is arranged in rows and columns with a current source for each column instead of a current source in each display cell. By omitting the current source from the cell, smaller display cell geometries are achieved. In a display where one row is selected at a time, the display of the present invention with smaller circuitry achieves performance identical to the prior art. Application is made to flat panel displays generally including field emission displays, liquid crystal displays, and integrated light emitting diode array displays.
Abstract:
An electron emitter plate (110) for an FED image display has an extraction (gate) electrode (122) spaced by an insulating layer (25) from a cathode electrode including a conductive mesh (118). Circular arrays (112) of microtips (14) are located concentrically within circular mesh spacings (116) on a resistive layer (15), within apertures (26) formed in extraction electrode (122). Microtips (14) are laterally spaced from mesh structure (118) by substantially identical paths of a ballast-providing resistive layer (15), placing all microtips (14) at generally the same potential.