JPH01112631A - Electron emitting element and its manufacture - Google Patents

Abstract

PURPOSE:To enhance the preciseness of an electron emitting part forming position and secure wide versatility for a surface conductive electron emitting element by performing formation of the electron emitting part and supply of emission current by the sue of each electrode. CONSTITUTION:A film 8 consisting of metal, semiconductor, etc., is formed on a base board 5. A conductive metal is laminated on the two ends of this film 8 so as to form electrodes 1, 2. The central neck of the film 8 is heated by performing current supply between these electrodes 1, 2, which forms an electron emitting part 4, whose position is defined by the use of specified electrodes 1, 2, and there is no risk of formation unnecessarily in other parts. Then electrodes 6, 7 for supply of emission current are formed by lamination of conductive metal on the two sides of the electron emitting part 4. These electrodes 6, 7 cover the other parts of the film deteriorated by current supply to enable driving with a low voltage. This raises the degree of freedom for the shape of film 8 and increases versatility.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to an electron-emitting device and a method for manufacturing the same.

[Prior Art] Conventionally, as an element that can emit electrons with a simple structure, for example, MI Ellingson (M, R.

The cold cathode device announced by E. Elinson and others is known.
tron.

Phys,) Volume 10, pp. 1290-1296, 1
965].

This device utilizes the phenomenon that electrons are emitted by passing a current through a small-area thin film formed on a substrate, and is generally referred to as a surface conduction type emission device. .

This surface conduction type emission device uses 5n02 (Sb) thin 11Q developed by Ellingson T., and A u 1. h by Il'l'
ttmer: ”Th1nSolid Films
”, vol. 9, p. 317, (1972)].

I To 7X, h Ilq by C M Hartwell and C G Fonstad “I
Eee Ee Trance''Ee Day Conf (M,
Hartwell and C, G, Fonsta
d: “IEEE Trans.

ED Conf,” ) p. 519, (1975)]
, and those using carbon thin films [Hisashi Araki et al.: "Vacuum", Vol. 26, No. 1, p. 22, (1983)] have been reported.

Typical device configurations of these surface conduction type emitters are shown in the third section.
As shown in the figure. In the figure, 2 and 2 are electrodes for obtaining electrical connection, 3 is a thin film made of an electron-emitting material, 4 is an electron-emitting portion, and 5 is a substrate.

Conventionally, in these surface conduction type emitters, an electron emitting portion is formed by an electrical heating treatment called preforming before electron emission. That is, a voltage is applied between the electrode 1 and the electrode 2! With one knife, thin film 3
The electron emitting function is obtained by energizing the thin film 3 and locally destroying, deforming or deteriorating the thin film 3 by the Joule heat generated thereby to form an electron emitting portion 4 in an electrically high resistance state.

[Problem that the invention seeks to solve] However,
The above conventional example has the following drawbacks when applied as an electron-emitting device.

(1) Since forming is performed by applying a high voltage, deterioration such as a decrease in electrical conductivity is observed in parts of the thin film that do not have an electron-emitting function.

(2) The position of the electron emitting portion formed by forming tends to vary depending on the device.

(3) The shape of the element is limited by forming conditions and the like.

Due to the above-mentioned problems, surface conduction type emissive Yasuko
Although it has advantages such as a simple device structure and high electron emission efficiency, it has not been actively applied in industry.

SUMMARY OF THE INVENTION An object of the present invention is to solve these conventional drawbacks and provide an electron-emitting device that is easy to use and a method for manufacturing the same.

[Means for Solving the Problems] That is, the present invention provides an electron-emitting device in which a thin film having an electron-emitting region is provided on a substrate. This is an electron-emitting device characterized by having an electrode for supplying an emission current to an electron-emitting device.

Furthermore, the present invention provides a method for manufacturing an electron-emitting device in which a thin film having an electron-emitting region is provided on a substrate, in which an electrode for forming the electron-emitting region is provided after the thin film is formed, and the electron-emitting region is formed by an electrical heating treatment. The method of manufacturing an electron-emitting device is further characterized in that electrodes for supplying an emission current to the electron-emitting region are provided on both sides of the electron-emitting region.

[Example] FIGS. 1(a) and 1(b) are a top view and a sectional view showing an example of an electron-emitting device of the present invention, in which 1.2 is an electrode for forming, and 3 is an electrode for forming. Thin film, 4 is an electron emission part formed by forming, 5 is a substrate, 6.7
is a driving electrode.

An electron emitting region 4 is formed in the thin film 3 by applying a voltage between the electrodes 1.2, and an emission current is then obtained from the electron emitting region 4 by applying a voltage between the deposited electrodes 6.7.

In this example, L1=0.5mm, LH・=30IL
m, l = 0.3 mm.

W = 5 mm, ω = 0.1 mm.

Conventionally, when soda glass is used as a substrate, the position of the electron-emitting portion varies widely depending on the device. Thin It! to eliminate variations! If the 2-bump portion is shortened, the heat required for forming will escape to the forming electrode, which will require a further increase in power and cause cracks in the glass substrate. Therefore, considering yield and reproducibility, 2:0.3 mm and ω=0.1 mm in FIG. 1 seem to be appropriate.

Using Sn02 as the thin film material, the size of the neck part is 0.
．． 3 mm, and ω = 0.1 mm, the resistance value of the thin film neck portion is approximately 300 Ω before forming, but it becomes high temperature due to forming, and after forming, the resistance value increases to approximately 1 Ω or more, excluding the electron emitting portion. The electron emitting portion has a resistance of several tens of Ω. In the conventional example where this element is driven as is, the driving voltage becomes high, but with the present invention,
For example, when the drive electrode is placed 1 in FIG. 1 so that L2=30B, the resistance becomes high among 7' and h Ilq.
Since most of the area other than the vicinity of the electron emitting part can be covered, emitted electrons can be obtained with a low driving voltage.

FIGS. 2(a) to 2(d) are process diagrams showing an example of the method for manufacturing the electron-emitting device of the present invention. First, place the same figure (a) on the board 5.
) A coating 8 made of metal, semiconductor, etc. is formed as shown in FIG. 2(a).

Next, electrodes 1.2 are formed by laminating conductive metal on both ends of the coating 8 (see FIG. 2(b)).

Thereafter, when electricity is applied between the electrodes 1 and 2, the central neck portion of the coating 8 is heated and forming occurs, forming the electron emitting portion 4 (see FIG. 2(c)).

Furthermore, electrodes 6.7 are formed by laminating conductive metal on both sides of the electron emitting part 4, and an electron emitting element is obtained (
(See Figure 2(d)).

In the present invention, the material of the thin film forming the electron-emitting region is not particularly limited, and a wide variety of commonly used materials can be used, such as 5na2. In
Any of metal compounds such as 2O3 and PbO, metals such as Au and Ag, carbon, and various other semiconductors can be used.

The thickness of the thin film may be any thickness used in normal surface conduction type emitters, and specific examples thereof vary depending on the type of material used, but are usually 0. O1-5μl,
Preferably it is 0.01 to 2 hours.

In addition, the electrode members for both forming electrodes and driving electrodes are not particularly limited, and a wide range of commonly used materials can be used, such as Ni, P, etc.
Metals such as T, Af, Cu, and Au and other conductive materials can be used.

Note that by cutting out the vicinity of the electron-emitting portion (as shown in FIG. 1), the electron-emitting device can be miniaturized, making it possible to use multiple devices and widening the range of applications.

Furthermore, by adjusting the position at which the vicinity of the electron-emitting region is cut out, the position of the electron-emitting region, which tends to vary depending on the device, can be unified.

[Effects of the Invention] As explained above, the following effects can be obtained by newly providing an electrode after forming.

(1) Conventionally, the electrode position and the size of the thin film neck part were determined based on the balance between forming and driving, but by providing a new drive electrode, the electrode position for forming, material, and size of the thin film neck part were determined The size can be optimally selected for forming, thereby improving device reproducibility and yield.

(2) By covering the parts of the thin film other than the electron emission lines, which have deteriorated due to forming, such as a decrease in electrical conductivity, with a driving electrode, it is possible to drive the thin film at a lower voltage than in the conventional example.

(3) The degree of freedom in the shape of the electron-emitting device increases.

[Brief explanation of the drawing]

FIGS. 1(a) and (b) are a plan view and a cross-sectional view showing an example of an electron-emitting device of the present invention, and FIGS. 2(a) to (d) are an example of a method for manufacturing an electron-emitting device of the present invention. The process diagram shown in FIG. 3 is a plan view of a conventional electron-emitting device. 1.2... Electrode, 3... Thin film, 4...
Electron emission part, 5... Substrate. 6.7... Electrode, 8... Coating. Agent Yutaka 1) Zen Yu Hayabusa 1 Zuto 2 Zu

Claims (1)

[Scope of Claims] 1) In an electron-emitting device in which a thin film having an electron-emitting region is provided on a substrate, an electrode for forming the electron-emitting region and a method for supplying an emission current to the electron-emitting region by energization heating treatment. An electron-emitting device characterized by having an electrode. 2) In a method for manufacturing an electron-emitting device in which a thin film having an electron-emitting portion is provided on a substrate, an electrode for forming the electron-emitting portion is provided after the thin film is formed, and the electron-emitting portion is formed by heating with electricity, A method for manufacturing an electron-emitting device, further comprising providing electrodes on both sides of the electron-emitting region for supplying an emission current to the electron-emitting region.