Abstract:
An electron emitting device is provided with a p-semiconductor layer formed on a semiconductor substrate. The p-semiconductor layer is composed of a diamond layer.
Abstract:
A planar doped barrier region of semiconductor material is coupled to a vacuum or gaseous region to provide electron emission from the planar doped barrier region into the vacuum or gaseous region. When a voltage is applied across the planar doped barrier region electrons flow from one end of the region to another. This flow results in the emission of electrons if the work function of the emission surface is less than the bandgap of the semiconductor material. The device of the present invention can be used as a vacuum microelectronic emitter, a vacuum microelectronic transistor, light source, klystron, or travelling wave tube.
Abstract:
An electron beam apparatus comprising a semiconductor electron emitter whose emissive surface dimensions are determined by dimensions of a p-n junction provided in the semiconductor element. By optimizing the dimensions of the emissive surface in relation to the electron-optical properties of the apparatus, an emitter is realized which combines optimum beam formation or imaging with a sufficiently large beam current and a high beam current density as required by the apparatus.
Abstract:
An electron-emitting surface is provided with a material reducing the electron work function, which is obtained from a suitable reaction. The reaction mixture or the product to be decomposed, for example CsN.sub.3, is present in a surface depression of a semiconductor body, while one or more pn junctions act as a heating diode. Upon heating, cesium is released and deposited on the electron-emitting surface.
Abstract:
A Field Emitter Array comprising a semiconductor substrate with an emitterurface formed thereon. A plurality of emitter pyramids is disposed on the emitter surface for emitting an electron current. The magnitude of the electron current emitted by each emitter pyramid I.sub.max, is controlled by a reverse-biased p-n junction associated with each emitter pyramid where I.sub.max =j.sub.sat X A.sub.p-n, j.sub.sat being the saturation current density and A.sub.p-n being the area of the reverse-biased p-n junction associated with each emitter pyramid. A grid, positively biased relative to the emitter surface and the emitter pyramids, is disposed above the emitter surface for creating an electric field that induces the emission of the electron current from the emitter tips.
Abstract:
An electron source having good electron emission efficiency comprises a silicon or other semiconductor body (10) having an n-type first region (3) which is separated from an n-type or p-type second region (2) by a barrier. The barrier may be a p-n junction between p-type region (2) and the n-type region (3), or it may be a p-type region (1) forming p-n junctions with the n-type regions (2 and 3). By means of electrode connections (13 and 12) to the first and second regions (3 and 2) a potential difference (V) is applied across the barrier so as to bias the first region (3) positive with respect to the second region (2) and thereby to establish a supply of hot electrons (24) injected from the second region (2) across the barrier into the first region (3). These hot electrons (24) are emitted into free space (20) from a surface area (4) of the body (10) which may have a caesium coating (14) to reduce the electron work function. A surface region (5) which may be depleted even at zero bias adjoins the surface area (4) and comprises a p-type doping concentration which serves to form in the body (10) a potential peak which is spaced from the surface area (4) from which the hot electrons (24) are emitted to provide an adjacent drift field (15) which accelerates electrons (24) towards this surface area (4) so assisting the electron emission. The electron sources may be used in cathode-ray tubes, display devices and even electron lithography equipment.
Abstract:
The invention relates to a semiconductor cathode and a camera tube and a display tube, respectively, having such a cathode, based on avalanche breakdown in a p-n junction extending parallel to the surface of the semiconductor body. The released electrons obtain extra energy by means of an accelerating electrode provided on the device. The resulting efficiency increase makes the manufacture of such cathodes in planar silicon technology practical. Since the depletion zone of the p-n junction upon avalanche breakdown does not extend to the surface, the released electrons show a sharp, narrow energy distribution. This makes such cathodes particularly suitable for camera tubes. In addition they find application, for example, in display tubes and flat displays.
Abstract:
An electron emitter comprising a body of a semiconductor material which is adapted to generate light therein when properly biased but which is a poor absorber of the generated light. On a surface of the body is a thin region of a semiconductor material which is a good absorber of the generated light and which has an index of refraction which substantially matches the index of refraction of the material of the body. The thin semiconductor material region is adapted to absorb the light from the body and convert the light into free electrons. On the surface of the semiconductor material layer is a thin film of an electropositive work function reducing material which is adapted to emit the electrons formed in the semiconductor material layer.