Futaba Denshi Kogyo K.k.

Agency of Industrial Science and Technology

Other

National Institute of Advanced Industrial Science and Technology

Agency of Industrial Science and Technology Ministry of International

Director General Agency of Industrial Science and Technology

Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Kobe Steel, Ltd.

Director-general of Agency of Industrial Science and Technology

Electronical Laboratory, Agency of Industrial Science and Technology

Seigo Kanemaru

Junji Itoh

Shigeo Itoh

Teruo Watanabe

Norio Nishimura

Makoto Yamamoto

Keisuke Koga

Akinori Shiota

Masayoshi Nagao

Hisashi Nakata

Makoto Miyamori

Takayuki Hirano

Takahiro Niiyama

Kazuhiko Tsuburaya

Yoshitaka Kagawa

Masaharu Tomita

Akira Inoue

A stable field-emission electron source that does not suffer from a current drop even after a high-current density operation for a long time is provided. The field-emission electron source includes: a substrate; an insulating layer that is formed on the substrate and that has a plurality of openings; cathodes arranged at the respective openings in order to emit electron beams; a lead electrode formed on the insulating layer in order to control emission of electrons from the respective cathodes; and a surface-modifying layer formed on the surface of each of the cathodes emitting electrons, comprising a chemical bond between a cathode material composing the cathodes and a material different from the cathode material.

Field-emission electron source, method of manufacturing the same, and image display apparatus

A field emission electron source capable of achieving large current density is provided at low cost with good productivity. An insulating layer is formed on a substrate and has one or more openings; and an extraction electrode is formed on the insulating layer. In one or more of the openings, a plurality of emitters, each of which emits an electron by an electric field from the extraction electrode, are formed on the substrate.

Field emission source with plural emitters in an opening

A field emission cathode capable of emitting electrons under a low voltage. Lead-out electrodes are formed on an insulating layer and openings are formed at a lamination between the insulating layer and each of the lead-out electrodes. Emitters each are arranged in each of the openings. The insulating layer is provided on a lower surface thereof with a photoresist layer modified by heating. The modified photoresist layer is electrically connected through a resistive layer to a cathode electrode. The cathode electrode is formed in a pattern on a cathode substrate made of glass or the like. The emitters each are constituted by a distal end of each of projections of the modified photoresist layer exposed from the insulating layer. The photoresist is modified by heating, resulting in being provided with electrical conductivity and exhibiting stable electron emitting characteristics under a low voltage.

Reduced voltage field emission cathode and method for manufacturing same

A field emission cathode that can uniform the number of electrons emitted from each emitter and can prevent a line defect even when a gate electrode is electrically short-circuited with an emitter. The movement of electrons in a channel formed on the channel forming electrode is controlled by applying a positive voltage to the current control electrode, so that the current supplied from the cathode electrode to the emitter can be controlled. If the emitter is short-circuited with the gate electrode, the increased current density destroys the channel, so that the current supply to the emitter can be stopped.

Field emission cathode

A cold electron emission device including an emitter having a protrusion having a sharp tip and disposed at a first end of a semiconductor thin film formed on an insulation substrate; a cathode electrode disposed at a second end of the semiconductor thin film; at least one gate electrode disposed between the emitter and the cathode electrode for controlling a current flowing through the semiconductor thin film; an insulating layer arranged to cover the semiconductor thin film, cathode electrode and gate electrode, except for the emitter; and a lead electrode arranged on the insulating layer such that it surrounds the tip of the emitter, thereby making it possible to achieve a cold electron emission device with reliable current stability.

Cold electron emission device

A field emission device of simple structure enables stabilization and control of field emission current. Emission current is controlled by a plurality of control voltage systems. An emitter having a sharp tip is fabricated by processing a p-type semiconductor substrate, and an n-type source region is provided on the p-type semiconductor substrate surface at a position that is laterally separated from the emitter. An electrode layer having an aperture facing the apex portion of the emitter is provided on an insulating layer, the electrode layer extending to above the n-type source region. Voltage applied to the electrode layer to apply an extractor field to the apex portion of the emitter and to induce inversion layers at the emitter surface and the surface of the p-type semiconductor substrate. The electrode layer is divided into a plurality of electrodes. An extraction voltage is applied to one of these electrodes closest to the emitter, another electrode is connected to an X selection line and another to a Y selection line, thereby controlling emission current.

Field emission device

A field emission element including a gate and an emitter and capable of penting any of the element oxide layer from being formed on a tip of the emitter to prevent a decrease in emission current, unstable operation and an increase in noise. The gate has a surface formed of a material of oxygen bonding strength higher than that of a material for at least a tip surface of the emitter, so that oxygen atoms and molecules containing oxygen entering the gate may be captured by adsorption on the gate to prevent formation of any oxide layer on the emitter. When a portion of the emitter other than the tip surface is formed of a material of oxygen bonding strength higher than that of the material for the tip surface, formation of any oxide layer on the tip surface of the emitter is minimized.

Field emission element

A cold electron emitting device has an emitter base portion, an emitter projection portion and a source region, each of which is an n-type semiconductor, formed on a p-type silicon substrate. A metal film which serves as an extraction electrode and a gate electrode of FET is formed via an insulating layer on the region of the substrate which includes the peripheral regions of the emitter base portion and source region. This cold electron emitting device can be manufactured as follows. First, a conical emitter having an emitter projection portion and emitter base portion and a source region are formed on a p-type semiconductor substrate. Next, an insulating layer and a metal film, which becomes an extraction electrode and a gate electrode of FET, is formed on the substrate which includes peripheral regions of the emitter base portion and source region. Then, an n-type impurity is doped in the emitter and the source region to form an n-type emitter and an n-type source region. In this manner, it is possible to manufacture a cold electron emitting device, which has an excellent work precision for the sharp tip of the emitter projection portion and an excellent uniform structure and can stably emit a current.

Cold electron emitting device and method of manufacturing same

A field emission device of simple structure enables stabilization and control of field emission current. A three-dimensional emitter formed on a base member incorporates therein a source layer on the side in contact with the base member, a drain layer on the side of the distal end including a tip and a channel region layer between the source layer and the drain layer. A gate is formed near the emitter. A strong electric field generated by applying a voltage to the gate causes cold electrons to be emitted from the emitter tip and the voltage applied to the gate also controls the conductivity of the channel region layer, whereby the field emission current emitted from the tip of the emitter is stabilized and controlled.

Field emitter having source, channel, and drain layers

A field emission element features an emitter which has rectangular projections at its distal end capable of readily controlling the interval between electrodes in increments as small as sub-microns, in order to reduce the voltage at which the device starts field emission at the required level and to improve emission uniformity. An emitter (2,20), a collector (3,21) and a gate (5,22) are arranged on a substrate (1), which is formed with a recess (4) in proximity to the electrodes (2,3,20,21) other than the gate (5). The gate (5) is provided in the recess (4).

Field emission element and process for manufacturing same

A field emission cathode capable of reducing an operation voltage and substantially preventing damage of an emitter. An emitter is provided on a substrate. The emitter includes a base and a plurality of rectangular tips projecting from the base. A gate is arranged in a recess formed on the substrate so as to be in proximity to the emitter. A width a of the tips of the emitter and an interval b between the tips are defined to satisfy a relationship of b/a=2. This permits an electric field strength applied to the tips of the emitter to be substantially increased as compared in a conventional field emission cathode of b/a.ltoreq.1, resulting in an operation voltage being reduced and a sufficient amount of emitter current being produced.

A field emission element including a gate and an emitter and capable of preventing any of the element oxide layer from being formed on a tip of the emitter to prevent a decrease in emission current, unstable operation and an increase in noise. The gate has a surface formed of a material of oxygen bonding strength higher than that of a material for at least a tip surface of the emitter, so that oxygen atoms and molecules containing oxygen entering the gate may be captured by adsorption on the gate to prevent formation of any oxide layer on the emitter. When a portion of the emitter other than the tip surface is formed of a material of oxygen bonding strength higher than that of the material for the tip surface, formation of any oxide layer on the tip surface of the emitter is minimized.

A field emission element in which the emitter has rectangular projections at its distal end capable of readily controlling the interval between electrodes in increments as small as sub-microns, in order to reduce the voltage at which the device starts field emission at the required level and to improve emission uniformity. An emitter (2,20), a collector (3,21) and a gate (5,22) are arranged on a substrate (1), which is formed with a recess (4) in proximity to the electrodes (2,3, 20,21) other than the gate (5). The gate (5) is provided in the recess (4).

An image display device capable of minutely setting the interval between an emitter (6) and a gate (5) with high accuracy and of being driven at a significantly reduced drive voltage with good emission uniformity. Each emitter (6) is provided in a recess in a substrate (2), so that the interval between the emitter (6) and a gate (5) is determined depending upon the thickness of the emitter (6). Thus, the interval can be readily controlled by adjusting or varying the period of time during which the film for the emitter (6) is formed, resulting in a micro-interval of the order of sub-microns between the two components being possible with high accuracy.

Growing community of inventors

Tsukuba, Japan

Seigo Kanemaru