Abstract: An analysis threshold determination device includes a threshold determination unit for determining a pair of or plural pairs of thresholds used for analysis in accordance with a pair of thresholds generated by a calculation unit and a count value output from a pulse count unit. The calculation unit repeatedly generates a new pair of thresholds in which at least one of the pair of thresholds is changed every time the pulse count unit counts the pulse until reaching a predetermined value. The threshold determination unit chooses a class of a measure of central tendency according to a frequency distribution defining each pair of thresholds generated as a class and the count value output from the pulse count unit as a frequency. The threshold determination unit determines a pair of or plural pairs of thresholds corresponding to a class of a predetermined range from the class of measure of central tendency.

Abstract: An impregnated cathode comprising a cathode obtained by impregnating pore portions of a refractory porous substrate with an electron emissive material containing Ba and formed thereon a plurality of thin films made of a high melting metal and Sc, or a high melting metal and a Sc oxide, or a high melting metal, Sc and a Sc oxide, or a high melting metal and a compound of Sc, W and O, said thin films having the same composition but different densities can maintain good emission characteristics even after the sealing off step of tube production because the thin films formed on the cathode surface are oxidation-resistant.

Abstract: An impregnated cathode comprising a refractory porous body whose pore parts are impregnated with an electron emissive material including barium and a thin film layer comprising tungsten, scandium and/or an oxide of scandium, deposited on the surface of the refractory porous body, characterized in that the thin film layer contains an oxide of tungsten, and/or an oxide of tungsten and scandium, has a distinguished electron emission property and a long life.

Abstract: The present invention relates to an impregnated cathode produced by attaching at least two layered thin films, the thin films comprising an under layer consisting of a high melting point metal thin film composed of, for example, Os, Ru, Rh, Pd, Ir, Pt, Re, Mo, W, Ta, etc., and an over layer consisting of a high melting point metal layer which contains Sc.sub.2 O.sub.3 and which is placed over the layer, on the surface of the impregnated cathode pellet generated by impregnating a refractory porous base body with electron emissive materials. The invention relates also to an electron tube having this cathode. This cathode maintains a low work functional mono-layer stably for a long period of time on its surface.

Abstract: The surface of a specimen such as a semiconductor wafer is processed and analyzed by the irradiator of the surface with an ion beam. The zone of the specimen to be processed and analyzed is kept by heating at a temperature higher than the melting point of an element or compound forming the ion species used for the irradiation. The means used for this heating may be an electron beam source, a light source, a resistance heating source, or a high-frequency heating source.

Abstract: A thin film formation technique and apparatus therefor which comprises converting a molecular beam effusing from a molecular beam source equipment to a pulsed molecular beam; introducing the pulsed molecular beam into an ionization chamber in such a fashion that the most of the pulsed molecular beam is caused to be incident to a substrate while a part is ionized by the ionization chamber; amplifying the ion or the electron converted from the ion and converting it to an electrical signal; calculating the flux and speed of the molecular beam; controlling the molecular beam effusing from the molecular beam source equipment on the basis of the calculation information; and forming the thin film on the substrate.

Abstract: An impregnated cathode comprising a refractory porous body impregnated with an electron emissive material and having an electron emissive surface, and a thin film disposed on the electron emissive surface and composed of a refractory metal and one of Sc, scandium oxide and a mixture thereof. The thin film containing Sc or scandium oxide is generated on the body in subsequent to impregnation of the electron emissive material into the refractory porous body with the result that a mono-atomic layer composed of Ba, Sc and O is maintained on the electron emissive surface over a long period of use.

Abstract: An impregnated cathode comprises a porous refractory substrate of refractory material such as tungsten containing at least one of scandium oxide particles and oxide particles containing scandium such as (Al, Sc).sub.2 O.sub.3, and an electron emissive material impregnated into pores of the substrate, and has an operating temperature lower by about 300.degree. C. than that of the conventional impregnated cathode containing no scandium oxide particles, or scandium.

Abstract: A field emission cathode of the present invention is characterized by the possession of a special layer which is adsorbed onto the surfaces of a tip that is joined to the top of a hairpin-shaped filament.This layer is formed by adsorbing a selected metal via oxygen to a thickness which does not exceed the thickness of the monolayer of atoms.The metal will be selected from chromium, aluminum, cerium, magnesium, titanium, silicon, zirconium or hafnium.The field emission cathode features that the electrons are emitted in a concentrated manner from a particular crystal plane among the crystal planes of the tip.Therefore, it is possible to obtain a field emission cathode having very small emission angle of electrons.

Abstract: A directly heated cathode for an electron tube comprising a base plate made of an alloy containing 20 to 30% by weight of W, 0.12 to 0.28% by weight of Zr and the remainder being Ni and an electron emissive oxide layer disposed directly on the base plate shows good and stable electron emission properties and when it is installed in a television picture tube, the picture tube shows excellent initial properties.

Abstract: An electron tube cathode has a composite suppression layer structure interposed between the base metal and the electron-emitting material to suppress an interface layer formed through the reaction of the base metal with the electron emissive material. The composite layer structure includes a thin layer of Pt or Re and a layer of oxide of Zr and/or Hf. As a result, the formation of the interface layer is prevented so that the useful life of the electron tube cathode is prolonged.

Abstract: An electron tube cathode in such a structure comprising a Ni-W-Zr alloy (W content: 20-28 wt. %) having a grain size of 4-10 .mu.m as a base metal, a 1,000-2,000 A-thick Pt film provided on the surface of the base metal, and an electron emitting material layer consisting of alkaline earth metal oxide provided on the Pt film has less emission lowering and less peeling of the electron emitting material layer, even if placed in a long time service. The electron tube cathode can be produced according to a method comprising (i) a step of annealing a base metal of Ni-W-Zr alloy (W content: 20-28 wt. %) at 1,000.degree.-1,200.degree. C., (ii) a step of providing a 1,000-2,000 A thick Pt film on the surface of the base metal, and (iii) a step of providing an electron emitting material layer consisting of alkaline earth metal oxide on the Pt film.

Abstract: A cathode for an electron source according to this invention comprises an emitter tip made of an electron emissive material, a filament for holding the emitter tip, and a binder for binding the emitter tip and the filament, the filament and the binder being made of glassy carbon. The binder can have a carbide or boride powder incorporated therein. The cathode according to this invention can be produced by using a thermosetting resin of predetermined shape as the starting material of the filament, fixing the emitter tip to a predetermined position of the thermosetting resin with the adhesive agent made of the raw thermosetting resin, and heating the resultant assembly in a non-oxidizing atmosphere to carbonize the resinous portions. This cathode is structurally very simple. Moreover, the adhesion between the filament and the emitter tip is excellent, and the emitter tip can be heated to high temperatures above 2,000.degree. C. by causing current to flow through the cathode.

Abstract: A stabilizing method is provided wherein a field emission cathode is subject to heat treatment of 2,000.degree.C. to 3,000.degree.C. in a hydrogen gas atmosphere of 1 .times. 10.sup..sup.-9 Torr to 5 .times. 10.sup..sup.-7 Torr and hereinafter an electric field in excess of 10.sup.7 volt/cm is applied to the cathode, whereby the emitted electron beam current from the cathode can be maintained constant for a long time.

Abstract: An electron emissive material of the formula (Y.sub.1.sub.-x EU.sub.x)B.sub.6 having the calcium hexaboride type crystal structure can easily produce hexaborides of the single phase. These borides have a number of merits such as small work function, high mechanical properties and low vapor pressure, and they are far more excellent than prior-art materials when used in a thermionic emission cathode and a field emission type cold cathode.