JPH02250232A - Electron multiplying material and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide an electron multiplying material, which is stable in electric properties and easy to fabricate by allowing it to chiefly contain glass and oxide type electroconductive substance, and embodying it in an electroconductive path structure in which particles of the electroconductive substance are continued in meshes. CONSTITUTION:An electron multiplying material concerned contains chiefly glass 1 and an oxide type electroconductive substance 2, being embodies in an electroconductive path structure where particles of the electroconductive substance 2 are continued in meshes. The electroconductive substance 2 consists of RuO2 or pyoclore type Ru compound, or otherwise a mixture thereof. When incident electrons 4 bombard this electron multiplying material 3 with a certain energy, secondary electrons 5 are emitted. At this time, negative electric charges are in shortage on the surface of the electron multiplying material 3, but it is practicable to feed electrons to the surface through RuO2 continued in meshes, which provides a response speed satisfactory for practical service. Thus an electron multiplying material is obtained, which is stable in electric properties and easy to fabricate.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electron multiplier material using glass for a secondary electron multiplier used for doubling and detecting charged particles, and a method for manufacturing the same.

BACKGROUND OF THE INVENTION In recent years, secondary electron multipliers using glass have mainly been microchannel plates (hereinafter referred to as MCP) formed by bundling a large number of thin glass tubes. MCPs are conventionally used as secondary electron multipliers in image tubes, and are also being used as secondary electron multipliers in flat panel image display devices.

A conventional electron multiplier material using glass will be explained below. In order to use glass as an electron multiplier material, it is desirable to use a stable material with a high secondary electron emission ratio and appropriate conductivity. Conventional materials for making glass conductive include: (1) glass containing a large amount of PbO treated with hydrogen reduction to form a conductive layer of Pb on the surface, and (2) metal oxides and intermetallic materials added to ordinary glass. (3) Ordinary glass with conductive layer deposited on it, such as Fe2's, V2O5, W Og
There are also those containing transition metal compounds such as .

Problems to be Solved by the Invention These conventional materials are: (1) Even if a conductive layer is formed by once reducing PbO, the conductivity changes due to subsequent heat treatment, etc., and is unstable. In addition, the reduction process itself to form a stable conductive layer is difficult. (2) Since the glass surface is not flat in most cases, it is difficult to deposit a uniform conductive layer. (3) Fears etc. are applied to the glass. When added, the properties of the material itself, such as the viscosity of the glass, change, making it difficult to obtain a secondary electron multiplier with a desired shape.

It is an object of the present invention to solve the above-mentioned problems of the prior art and to provide an electron multiplier material that has very stable electrical properties such as conductivity and is easy to manufacture and process, and a method for manufacturing the same.

The present invention aims to solve the problems of the prior art.

Means for Solving the Problems The present invention includes (1) glass and an oxide conductor as main raw materials, and has a conductive path structure in which particles of the oxide conductor are connected in a network.

(2) The oxide conductor is RuO2, a pyrochlore type Ru compound, or a mixture of both.

(3) The glass is a low melting point glass containing 50% or more of PbO.

(4) A mixture containing glass particles and oxide conductor particles as main raw materials is fired or sintered at a high temperature of 300° C. or higher.

(5) The mixture is made into a paste, shaped using a printing process, and then sintered.

Effects of the present invention, since the conductor material is connected in a network,
Its electrical properties are very stable. Further, since particles such as RuO2 are mixed with glass and sintered, there is little change in the properties of the glass itself, so an electron multiplier material that is easy to manufacture and process can be obtained.

Examples Examples of the present invention will be described below with reference to the drawings.

FIG. 1(a) shows that RuO* is added to the powder of frit glass 1.
This is an enlarged view of a part of the cross section of the powder obtained by mixing the powders of Frit Glass 1 and Ru 02 in a vehicle, or by drying the powder mixed with some additives.
The powder from No. 2 is mixed as shown in the figure. Since this mixture is in the form of a paste, the desired shape and pattern of the electron multiplier material can be easily created using printing technology.

In addition, by using the printing process, manufacturing costs can be kept low compared to conventional processing and forming methods.

Figure 1(b) shows that the above mixture was heated at 400 °C in an air atmosphere.
It is fired (sintered) at ~500℃ and is an electron multiplier material 3.
The cross-section of the material differs slightly depending on the firing conditions, but it generally looks like the one shown in this figure.

The state of the particles after firing is as shown in FIG. 1(b), in which the particles of the frit glass 1 are surrounded by the particles of Ru (L2), forming a network. This can be achieved extremely easily by using frit glass with a low melting point and firing at a high temperature.Electron multiplier material 3
The electrical properties such as resistance value are determined by the electrical properties of this mesh-like conductive path. Therefore, the resistance value of the electron multiplier material can be controlled by the mixing ratio of the frit glass 1 and RuOa 2, the firing temperature, etc.

Here, the average particle size of the frit glass 1 powder before firing is 0.1 to 10 μm, and the average particle size of the Ru0z2 powder is 0.
．． 01-1 μm. By selecting and using an appropriate inorganic oxide as an additive, it is possible to control the electrical properties such as the resistance value and TCR of the electron multiplier material 3 after firing to a certain extent. It is well known for its research on resistors.

The secondary electron emission ratio δ of the electron multiplier material 3 after firing is often approximately the same as that of glass, and is approximately between 2 and 4. Therefore, as an electron multiplication material using glass,
It is a material with a relatively high secondary electron emission ratio and suitable conductivity.

In FIG. 1(b), when incident electrons 4 collide with electron multiplier material 3 with appropriate energy, secondary electrons 5 are generated. At this time, there is insufficient negative charge on the surface of the electron multiplier material 30, but through the Ru0a2 connected in a network,
It is possible to supply electrons to the surface and has a response speed sufficient for practical use.

As described in detail, the present invention contains glass and an oxide conductor as main raw materials, and has a conductive path structure in which particles of the oxide conductor are connected in a network, so that electrical properties are improved. An electron multiplier material that is extremely stable and easy to manufacture and process can be obtained.

[Brief explanation of drawings]

FIG. 1(a) is an enlarged sectional view of a part of the formation process of the electron multiplier material in one embodiment of the present invention, and FIG. 1(b) is a partial enlarged sectional view of the electron multiplier material in the same embodiment. It is an enlarged sectional view. 1...Frit glass, 2...RuO□, 3...
Electron multiplication material, 4... incident electron, 5... secondary electron.

Claims (5)

[Claims] (1) Contains glass and oxide conductor as main raw materials,
An electron multiplier material characterized in that the particles of the oxide conductor have a conductive path structure in which particles of the oxide conductor are connected in a network. (2) The electron multiplier material according to claim 1, wherein the oxide conductor is RuO_2, a pyrochlore type Ru compound, or a mixture of both. (3) The electron multiplier material according to claim 1 or 2, wherein the glass is a low melting point glass containing 50% or more of PbO. (4) The glass is a low melting point glass containing 50% or more of PbO, and a mixture containing particles of the glass and particles of the oxide conductor as main raw materials is fired at a high temperature of 300°C or more. Alternatively, a method for producing an electron multiplier material characterized by forming it by sintering. (5) A mixture containing glass particles and particles of the oxide conductor as main raw materials is made into a paste, shaped using a printing process, and then sintered. A method for manufacturing the electron multiplier material described above.