Futaba Denshi Kogyo K.k.

Agency of Industrial Science and Technology

Other

Fuji Electric Co., Ltd.

Agency of Industrial Science and Technology Ministry of International

Director General Agency of Industrial Science and Technology

Director-general, Jiro Hiraishi, Agency of Industrial Science and

Kobe Steel, Ltd.

Director-general of Agency of Industrial Science and Technology

Electronical Laboratory, Agency of Industrial Science and Technology

Junji Itoh

Seigo Kanemaru

Shigeo Itoh

Teruo Watanabe

Norio Nishimura

Hisashi Nakata

Kazuo Matsuzaki

Masato Nishizawa

Yoichi Ryokai

Takahiko Uematsu

Makoto Miyamori

Takayuki Hirano

Takahiro Niiyama

Toshihiko Kanayama

Kazuhiko Tsuburaya

Masaharu Tomita

Yoshitaka Kagawa

Akira Inoue

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

In a comb-like or wedge-like electron emitting device, an emitter or both an emitter and an anode electrode are processed from a single-crystal silicon thin film of an SOI wafer. The single-crystal silicon thin film in portions other than the processed portion is removed so that the silicon oxide layer is dug down further slightly. A gate electrode for applying an electric field in order to draw electrons out of the emitter is provided in the dug-down portion. When the end and side faces of the emitter are formed as (111) faces by anisotropic etching in the condition that the single-crystal silicon thin film is oriented to a (100) face, the emitter has a sharp edge at about 55.degree. with respect to the substrate. In a conical electron emitting device, the gate electrode is constituted by a single-crystal silicon thin film of an SOI wafer so that a pyramid surrounded by the (111) faces is formed on the single-crystal silicon substrate.

Field emission type electron emitting device and method of producing the

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

Field emission type electron emitting device with convex insulating

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.

Image display device

A relative displacement among a plurality of objects is measured with a high degree of accuracy by utilizing diffraction and interference phenomena of waves through diffraction gratings formed on the objects. Forming diffraction gratings on a plurality of objects, aligned or registered with each other, a wave is made incident to the diffraction gratings, thereby diffracted waves are obtained. A phase difference of the diffracted waves is measured. As a result, relative-displacements among the plurality of objects are obtained with a high degree of accuracy.

Growing community of inventors

Tsukuba, Japan

Junji Itoh