JPH0765699A - Electron emission device, manufacture thereof, and image forming equipment - Google Patents

Abstract

PURPOSE:To decrease dispersion of characteristics independent of environment by covering the surface of a transition element or a transition element compound interposed between a pair of electrodes with a typical element or a typical element compound in the III group of the periodic table. CONSTITUTION:An electron emission device interposes a transition element and/or a transition element compound between a pair of electrodes, and emissions electrons by applying voltage across the electrodes. In the electron emission device, the surfaces/surface of the transition element and/or the transition element compound are/is covered with a typical element or a typical element compound in the III group of the periodic table. The surface is covered with an element, which is chemically stable and capable of covering the surface, of the typical elements or the typical element compounds. The variation of electron emission effect caused by an environmental factor can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron-emitting device using a transition element and / or a compound of a transition element, a method for manufacturing the same, and a display device.

[0002]

2. Description of the Related Art Conventionally, two types of electron-emitting devices are known, a thermoelectron source and a cold cathode electron source. The cold cathode electron source includes a field emission type (FE), a metal / insulating layer / metal type (hereinafter abbreviated as MIM), and a surface conduction electron emitting device (SC).
E) etc.

As an example of the field emission type (FE), W.
P. Dyke & W. W. Dolan, "Field e
"Mission", Advance in Elect
ronPhysics, 8, 89 (1956) and C.I. A. Spindt, "Physical prop
erties of thin film-field
Emission cathodes with mo
lybdenum cones ”, J. Appl. Ph.
ys. , 47, 5248 (1976) and the like are known.

An example of the MIM type is C.I. A. Mea
d, "The tunnel-emission am
plier, J. et al. Appl. Phys. , 32, 6
46 (1961) and the like are known.

As an example of the SCE type, M. I. Elin
son, Radio Eng. Electron P
ys. 10 (1965) and so on.

SCE utilizes a phenomenon in which electron emission occurs when a current is applied to a thin film having a small area formed on a substrate in parallel with the film surface.

As the surface conduction electron-emitting device (SCE), one using the SnO ₂ thin film by the above-mentioned Erinson, one using the Au thin film [G. Dittmer: "T
"Hin Solid Films", 9, 317 (19)
72)], by In ₂ O ₃ / SnO ₂ thin film [M.
Hartwell and C.I. G. Fonstad:
"IEEE Trans.ED Conf.", 519
(1975)], by a carbon thin film [Hiraki Araki
Others: Vacuum, Vol. 26, No. 1, p. 22 (1983)] and the like are reported.

As a typical device configuration of these surface conduction electron-emitting devices, the above-mentioned M. The Hartwell device configuration is shown in FIG. In the figure, 1 is an insulating substrate. The electron emitting portion forming thin film 2 is composed of an H-shaped metal oxide thin film formed by sputtering, and the electron emitting portion 3 is formed by an energization process called forming described later. Four
Is a thin film including an electron emitting portion.

Conventionally, in these surface conduction electron-emitting devices, it has been general that the electron-emitting portion forming thin film 2 is formed with an electron-emitting portion 3 in advance by an energization process called forming before the electron emission. . That is, the forming means that a voltage is applied to both ends of the electron emitting portion forming thin film 2 to locally energize the electron emitting portion forming thin film to locally destroy, deform or alter the electron emitting portion forming thin film to make it into an electrically high resistance state. That is, the emission part 3 is formed. In some cases, the electron emitting portion 3 may have a crack in a part of the electron emitting portion forming thin film 2, and the electron may be emitted from the vicinity of the crack. Hereinafter, the thin film for forming an electron emitting portion including the electron emitting portion generated by forming is referred to as a thin film 4 including an electron emitting portion.

In the surface-conduction type electron-emitting device which has been subjected to the forming process, a voltage is applied to the thin film 4 including the above-mentioned electron-emitting portion and a current is caused to flow on the surface of the device so that the above-mentioned electron-emitting portion 3 emits electrons. It is a thing.

Among these conventional electron-emitting devices, MI
Transition elements are often used in the electron emitting portions such as M and SCE. In order to obtain a large current, it is preferable to use a substance having a large work function, that is, an element having a large atomic number in general. However, the group I and group II of the typical element are easily affected by moisture such as moisture absorption, and the group VII of the typical element is
It is difficult to hold the group or group VIII between the electrodes.
In addition, due to restrictions such as the manufacturing process and availability as raw materials, transition elements were often used as a result.

It has been conventionally known that the surface of the electron emitting material is coated with carbon or fluorine in order to prevent adsorption of water, carbon monoxide, benzene and the like to the electron emitting material. For example, JP-A-1-309242 discloses a carbonaceous coating method, and JP-A-2-247938.
The publication discloses fluorine coating methods, but all of them are simple methods of physically coating the surface of the electron emitting material to prevent adsorption.

[0013]

However, the conventional electron-emitting devices using the above transition elements have a common problem that the electron-emission efficiency varies and fluctuates, and is unstable and poor in reproducibility. was there. Due to such problems, the conventional surface-conduction electron-emitting device has not been positively applied industrially, despite the advantage that the device structure is simple. A device that is not easily influenced by the environment has been desired.

The present invention has been made in order to solve the conventional problems in view of the above points, and in the surface-conduction type electron-emitting device, the surface modification of the electron-emitting portion is performed so that the environment-dependent It is an object of the present invention to provide a stable electron-emitting device which has a long life and a small variation in characteristics.

[0015]

That is, the present invention is an electron-emitting device in which a transition element and / or a transition element compound is sandwiched between a pair of electrodes, and a voltage is applied between the electrodes to emit electrons. 2. An electron-emitting device characterized in that the surface of the transition element and / or the transition element compound is coated with a typical element or a typical element compound belonging to Group III of the periodic table.

Further, the present invention provides an electron-emitting device in which a transition element and / or a transition element compound is sandwiched between a pair of electrodes, and a voltage is applied between the electrodes to emit electrons. And / or a surface of the transition element compound is coated with a typical element or a typical element compound belonging to the fourth, fifth and sixth periods of Group IV of the periodic table.

Furthermore, the present invention provides an electron-emitting device comprising a transition element and / or a transition element compound sandwiched between a pair of electrodes, and applying a voltage between the electrodes to emit electrons. And / or the surface of the transition element compound is coated with a typical element or a typical element compound belonging to Group V fourth, fifth and sixth periods of the periodic table.

Further, the present invention provides an electron-emitting device in which a transition element and / or a transition element compound is sandwiched between a pair of electrodes, and a voltage is applied between the electrodes to emit electrons. And / or a surface of the transition element compound is coated with a typical element or a typical element compound belonging to Group VI fourth, fifth and sixth periods of the periodic table.

Further, the present invention is an image forming apparatus comprising the above-mentioned electron-emitting device and a phosphor.

Further, the present invention is an image forming apparatus comprising a plurality of the above-mentioned electron-emitting devices electrically connected to the wiring electrodes and arranged, and a phosphor.

In the present invention, after the transition element and / or the transition element compound is provided between the pair of electrodes, the transition element and / or the transition element compound is in a gaseous state in the above-mentioned typical element or typical element. A method for producing an electron-emitting device, which comprises causing a compound to act.

The present invention is also a recording method characterized by recording on a recording medium by using emitted electrons from the electron-emitting device or fluorescence or phosphorescence by the emitted electrons.

The electron-emitting device of the present invention has a first ionization potential or work function (eV) or more of the transition element and / or the transition element compound between a pair of electrodes sandwiching the transition element and / or the transition element compound. An element that emits electrons by applying the voltage (V) is preferable.

The present invention will be described in detail below.

The present invention is an electron-emitting device in which a transition element and / or a transition element compound is sandwiched between a pair of electrodes, and a voltage is applied between the electrodes to emit electrons. It is characterized in that the surface of the elemental compound is coated with a typical element or a typical elemental compound which is chemically stable and can be surface-coated.

According to the present invention, it is possible to reduce fluctuations in electron emission efficiency, which are considered to be caused by environmental factors, as compared with the conventional case.

Environmental factors that cause the fluctuation of the electron emission efficiency include the presence of water and carbon monoxide and benzene which are considered to be derived from a vacuum pump. That is, a substance capable of coordinating with a transition element such as H ₂ O (and OH ⁻ which seems to be produced by electrochemical decomposition), CO, or C ₆ H ₆ becomes a ligand, and the degree of vacuum, humidity, It is considered that the complex reaction mainly occurs on the surface of the transition element in an equilibrium state determined by the conditions such as temperature. Alternatively, it is possible that these substances are adsorbed and desorbed on the surface of the transition element.

When the above transition element or transition element compound (including complex or adsorbed state) is viewed as a single atom, when a voltage higher than the ionization potential is applied,
The electrons having the smallest ionization potential among the outer shell electrons are sequentially emitted.

When the above transition element or transition element compound (including complex or adsorbed state) is viewed as a bulk (assembly of molecules), when a voltage higher than the work function is applied, electrons are emitted from the Fermi level. It The difference between the ionization potential and the work function is whether the electrons are seen to be emitted from individual metal atoms or the banded bulk metal. As described in the prior art, electron-emitting devices have various device configurations, and which one is dominant depends on the individual electron-emitting mechanism. For example, in the case of the SCE element using the fine particles exemplified in the prior art, the contribution of electrons emitted from each metal is large.

In the case of complex formation, according to the theory of the ligand field, the splitting of the d orbital due to the static electricity of the ligand occurs,
The electronic state of the transition element changes. As a result, the ionization potential (first, second, ...) Of the d-electrons changes, so that the number of electrons that can be emitted changes if a constant voltage is applied (see FIG. 11).

Even in the case of adsorption, if the adsorbed molecule is a substance that is easily ionized, the transition function interacts with electrons to change the work function. In particular, when a voltage is applied, exchange of electrons between the adsorbed molecule and the transition element is likely to occur, and in some cases, complex formation may occur. Like the adsorption state, the work function also changes in the complex state. If the adsorption to the surface of the transition element is non-uniform in the plane, or if the adsorption is uniform in the plane but varies with time or temperature, the statistical number of electrons that can be emitted changes. .

According to the present invention, the surface of the transition element is coated with a typical element or a compound of the typical element that is more chemically stable than the transition element to prevent water, Even in the presence of substances such as carbon oxide and benzene which are environmental factors, complex formation did not substantially occur, and a stable electron-emitting device was obtained.

Further, by coating with a chemically stable typical element or a typical element compound, electrons on the surface of the transition element are hard to be exposed, and an electron-emitting device in which adsorption is less likely to occur was obtained. In the present invention, the transition element is a transition element when the elements of the chemical element periodic table are classified into a typical element and a transition element. The transition element compound is mainly a hydride, an oxide, a carbide, a nitride, a barogenide, etc. and a salt of a transition element, etc. In the case of an alloy with a typical element metal other than the above compounds, the transition element is used in a molar ratio. It is preferable that the content is 10% or more.

As a special case of the transition element compound, when the surface of the typical element is coated with the transition element or the above-mentioned general transition element compound, it is preferable that it occupies 20% or more of the surface area.

However, the preferable range of the above-mentioned transition element depends on the contribution of the transition element to all the emitted electrons when the electron-emitting device is used, or the contribution of the transition element that varies depending on environmental factors among all the emitted electrons. Therefore, it is not necessarily limited to the above range.

The first feature of the present invention is that when these transition elements or transition element compounds are used as an electron-emitting device, the surface thereof is coated with a typical element or a typical element compound as described later.

In the present invention, the term "coating" means a state of being laminated mainly by electrostatic or physical adsorption, but a state of forming an alloy or compound with a transition element or a transition element compound by a chemical reaction. But it's okay.

Even when electrostatically or physically adsorbed in the initial state, when a voltage is applied to this to emit electrons, the transition element is easily ionized to form an alloy or a compound. In some cases. Regeneration of alloys and compounds depends on whether the typical element is metal or non-metal.

Further, the electron-emitting device of the present invention is obtained by coating the surface of the above-mentioned transition element and / or transition element compound with a chemically stable and surface-coverable element of a typical element or a typical element compound. is there.

Of the typical elements, alkali metals of Group I, I
Group I alkaline earth metals form hydroxides by moisture absorption, have a low ionization potential (work function), are more easily ionized than transition elements, and are more likely to react with halogens, etc., and thus are stable against environmental factors.

On the other hand, the halogen of Group VII is highly reactive and unstable also to environmental factors, and like the inert gas of Group VIII, it is easily gasified, and it is possible to apply a voltage while holding it between the electrodes. Have difficulty.

Further, group IV carbon and silicon are likely to react with oxygen to form an oxide, and to adsorb various impurities.

Nitrogen and oxygen in the second cycle are gases at room temperature and atmospheric pressure, and compounds containing nitrogen and oxygen easily form a complex with a transition element or a transition element compound.

The phosphorus and sulfur in the third period are also likely to form a complex with a transition element or a transition element compound.

In the above definition of the coating of the present invention, what is included in the scope of the compound is a chemically stable one in which a transition element and a typical element are covalently bonded, and a complex in which the typical element is coordinated with the transition element. Is not preferable in the present invention because it may vary depending on environmental factors. Depending on the type of ligand, some of the above-mentioned nitrogen, oxygen, phosphorus, and sulfur may form a coating that is relatively stable against environmental factors, but since they are generally unstable, these elements are not included in the present invention. Absent.

Therefore, as the typical elements used in the present invention, all the groups III and IV of the periodic table, and V
It is an element belonging to the 4th period, the 5th period, and the 6th period of the VI group. Specifically, B, Al, Ga, In, Tl,
Ge, Sn, Pb, As, Sb, Bi, Se, Te, P
and the like.

The typical element compound may be a compound of the above typical elements, for example, B ₂ H ₆ or Al ₂ C
l ₆ , GaF ₃ , InF ₃ , TlCl ₃ , GeS, SnCl
₂ , Pd (NO ₃ ) _{2 and the} like.

Due to their chemical stability, the transition elements or transition element compounds coated with these typical elements or typical element compounds are directly contacted by the environmental elements to react with them or are adsorbed on the surface thereof. However, since it does not form a complex with the emission of electrons, the electron emission efficiency of the electron emission device becomes smaller and more stable than before. The following is a description of the basic configuration, manufacturing method and characteristics of the electron emission device according to the present invention. Outline. FIG. 1 is an explanatory diagram showing the structure of a basic electron-emitting device according to the present invention. In the figure, 1 is an insulating substrate, 5 and 6 are device electrodes, 4 is a thin film including an electron emitting portion, and 3 is an electron emitting portion.

In the thin film 4 including the electron emitting portion in the present invention, the electron emitting portion 3 is composed of a large number of conductive fine particles having a particle diameter of several Å, particularly preferably 5 Å to 500 Å. The thin film 4 including the electron emitting portion is a fine particle film. The fine particle film (thin film 4) is a film in which a plurality of fine particles are aggregated, and its fine structure is not only a state in which the fine particles are individually dispersed and arranged but also a state in which the fine particles are adjacent to each other or overlap each other (island). (Including the shape). The thickness of the thin film 4 is preferably several Å to several thousand Å, particularly preferably 10 Å to 200 Å.

Separately, the thin film 4 including the electron emitting portion may be a carbon thin film in which conductive fine particles are dispersed.

Specific examples of the thin film 4 including an electron emitting portion include Mn, Sc, La, Cr, Co, Fe, Ce and T.
i, Zr, Th, Cu, Ag, Au, Tl, Hg, C
Metals such as d, Hg, Pd, Pt, Ru, In, Zn, Ta, W, oxides such as VO ₂ , VO, MoO, PdO, PbO, HfB ₂ , ZrB ₂ , LaB ₆ , CeB ₆ , YB.
₄ , boride such as GdB ₄ , TiC, ZrC, HfC, T
Carbides such as aC and WC, nitrides such as TiN, ZrN, and HfN, AgMg, NiCu, and the like.

The thin film 4 including the electron emitting portion is formed by a vacuum vapor deposition method, a sputtering method, a chemical vapor deposition method, a dispersion coating method, a dipping method, a spinner method, or the like.

Various methods are conceivable as a method of manufacturing an electron-emitting device having the electron-emitting portion 3, one example of which is shown in FIG. Reference numeral 2 is a thin film for forming an electron emitting portion, and for example, a fine particle film can be mentioned.

The manufacturing method will be described below in order with reference to FIG.

1) After the insulating substrate 1 is thoroughly washed with a detergent, pure water and an organic solvent, the device electrodes 5 and 6 are formed on the surface of the insulating substrate 1 by the vacuum deposition technique and the photolinography technique ( FIG. 2A). Any material may be used as the material of the element electrode as long as it has conductivity. For example, Ni, Cr, Au, Mo, W,
Examples of the metal or alloy include Pt, Ti, Al, Cu, Pd, and the like. The element electrode spacing L1 is several hundred Å to several tens of μm, preferably 1 μm to 10 μm, and the element electrode length W1 is preferably several hundred Å. The film thickness d of the element electrodes 5 and 6 is preferably several hundred m to several thousand m.

2) Between the device electrodes 5 and 6 provided on the insulating substrate 1, an organic metal solution is applied to the insulating substrate on which the device electrodes 5 and 6 are formed and left to stand. , Forming an organometallic thin film. Incidentally, the organic metal solution means the above Mn, Sc, La, Cr, Co, Fe, Ce,
Ti, Zr, Th, Cu, Ag, Au, Tl, Hg, C
It is a solution of an organic compound containing a metal such as d, Hg, Pd, Pt, Ru, In, Zn, Ta and W as a main element. After that, the organic metal thin film is heat-fired and patterned by lift-off, etching, etc. to form the electron-emitting portion forming thin film 2 (FIG. 2B).

3) Subsequently, when an energization process called forming is applied by applying a voltage between the device electrodes 5 and 6 by a power source (not shown), the electron-emitting portion having a changed structure is formed at the site of the electron-emitting portion forming thin film 2. 3 is formed (FIG. 2 (c)). The electron-emitting portion forming thin film 2 is locally destroyed, deformed or altered by this energization process, and a portion whose structure is changed is called an electron-emitting portion 3. As described above, the electron emitting portion 3
The applicants have observed that is formed from a large number of conductive fine particles.

The characteristics of the electron-emitting device according to the present invention produced by the above manufacturing method are shown in FIG.
The measurement and evaluation device is used for measurement.

FIG. 3 is a schematic configuration diagram of a measurement / evaluation apparatus for measuring electron emission characteristics of the device having the configuration shown in FIG. In FIG. 3, 1 is an insulating substrate, 5 and 6 are device electrodes, 4 is a thin film including an electron emitting portion, and 3 is an electron emitting portion. Further, 31 is a power supply for applying a device voltage Vf to the device, 30 is an ammeter for measuring a device current If flowing through the thin film 4 including an electron emitting portion between the device electrodes 5, 6.
34 is an anode electrode for capturing the emission current Ie emitted from the electron emission portion of the device, 33 is the anode electrode 3
A high voltage power source for applying a voltage to 4 and an ammeter 32 for measuring the emission current Ie emitted from the electron emitting portion 3 of the device.

In measuring the above-mentioned device current If and emission current Ie of the electron-emitting device, a current 31 is applied to the device electrodes 5 and 6.
And an ammeter 30 are connected to each other, and an anode electrode 34 to which a current 33 and an ammeter 32 are connected is arranged above the electron-emitting device. Further, the electron-emitting device and the anode electrode 34
Is installed in a vacuum device, and the vacuum device is equipped with equipment necessary for the vacuum device such as an exhaust pump and a vacuum gauge (not shown), and the measurement and evaluation of this element can be performed under a desired vacuum. ing.

The voltage of the anode electrode is 1 kV to 10 kV.
kV, the distance H between the anode electrode and the electron-emitting device is 3 mm
It was measured in the range of ~ 8 mm.

The electron-emitting device of the present invention can be constructed by partially changing the structure and the manufacturing method thereof.

A cross-sectional view of a plane type SCE element as an example of the novel electron-emitting device according to the embodiment of the present invention is shown in FIG. 4, and the features, structure, and manufacturing method of the present invention will be outlined with reference to FIG. .

In the figure, 1 is an insulating substrate, 5 and 6 are device electrodes, 4 is a thin film made of an electron emitting material composed of a transition element, and 3 is an electron emitting portion. Reference numeral 11 is a typical element or a typical element compound. FIG. 4 shows a surface of a transition element coated with a typical element or a typical element compound 11.

As the method of manufacturing the electron-emitting device of FIG. 4, the electron-emitting device is prepared by the above-described method, and immediately after forming the electron-emitting portion 3, the typical element or the typical element compound is heated under reduced pressure to be vaporized. It is preferred to act as steam. The gaseous typical element or typical element compound selectively forms a complex with the transition element of the electron-emitting device. When the typical element or the typical element compound is deposited on the electrodes 5 and 6 and the insulating substrate 1 and adversely affects the electron emission, the typical element or the typical element compound is deposited by heating the entire electron-emitting device. While the complex formation reaction with the transition element is promoted by increasing the temperature.

FIG. 4 shows an initial state in which the transition element is adsorbed on the surface, but when a voltage is applied between the electrodes 5 and 6 to emit electrons, a transition element, a typical element or a typical element compound may be generated. There is also the possibility of changing into complex formation. Complex formation in this case may be a transient phenomenon only during voltage application, and depending on the complex formation stability constant, it may be stable in the complex state and may not return to the adsorption state shown in FIG. 4 even when the voltage application is stopped. There is also.

Although it has been conventionally performed to manufacture an electron-emitting device by using a complex as a coating material, in that case, a typical element or a typical element compound was decomposed by firing to obtain a transition element oxide. . In general, a complex has a low electric resistance and a high voltage of several volts cannot be applied to the complex, so that it is difficult to emit electrons. Therefore, the oxide was made to have high electric resistance by firing.

As another method, as a method of carrying out the reaction with the above-described typical element or typical element compound vapor even inside the thin film, the entire element is heated, or a current is passed between the electrodes to generate Joule heat. It is preferred to promote the complex formation reaction between the transition element and the typical element or the typical element compound by the method. Alternatively, it is also preferable to apply a voltage between the electrodes to electrochemically ionize the transition element so that the transition element easily reacts with the typical element or the typical element compound.

In addition to the thin film shown in FIG.
The present invention is also effective in the case of fine particles. Figure 5
Shown in. In the case of a fine particle shape, a typical element or a typical element compound or a complex reacting with a typical element or a typical element compound is generally formed on the surface of the particle with a substantially uniform thickness as shown in FIG.

However, in the case where the vapor of the typical element or the compound of the typical element is circulated or in the case where there is directionality such as vapor deposition, the vicinity of the portion contacting the insulating substrate 1 as shown in FIG. 5B. Has a thin coating. Even in such a state, it is possible to suppress the complex formation or adsorption of environmental factors on the surface, so that it is possible to reduce the fluctuation of all emitted electrons due to environmental factors.

The present invention may be either substantially uniform as shown in FIG. 5 (a) or nonuniform as shown in FIG. 5 (b).

In the method for manufacturing an electron-emitting device of the present invention, typically, a transition element and / or a transition element compound is provided between a pair of electrodes, and then the transition element and / or the transition element compound is vacuumed. It is carried out by reacting a gaseous typical element or a typical element compound.

More specifically, a movable isolation wall for controlling the isolation and connection of the vacuum chamber and another chamber connected to the vacuum chamber and a means for cooling and / or heating a typical element or a typical element compound provided in the separate chamber are provided. In the electron-emitting device processing apparatus described above, an electron-emitting device is installed in a vacuum chamber to create a vacuum state, and a typical element or a typical element compound is installed in a separate chamber and a cooling means is provided depending on the vapor pressure of the typical element or the typical element compound. While being used together, a vacuum state similar to that of the vacuum chamber is obtained, and after removing the molecules adsorbed on the surface of the electron-emitting device and / or conducting electricity in the vacuum chamber, the movable isolation wall is moved to form the vacuum chamber. Depending on the vapor pressure of a typical element or a typical element compound by connecting separate chambers, heating means may be used together to convert it to a typical element or a typical element. Things were the vapor to process the electron-emitting device by Sarasuru the electron-emitting devices typical element or typical element compound vapors.

The electron-emitting device of the present invention is a display device that displays an image by causing emitted electrons to collide with a phosphor to emit light, and a light-sensitive material using emitted electrons from the electron-emitting device or fluorescence or phosphorescence by the emitted electrons. By recording on a recording medium, it can be used in an image forming apparatus such as a recording apparatus.

[0075]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in more detail with reference to the accompanying drawings.

Example 1 A surface conduction electron-emitting device having a structure as shown in FIG. 1 was prepared as follows. The element shape is W = 10 mm,
L = 2 μm. 6 to 9 are explanatory views showing the manufacturing method.

1) A quartz substrate is used as the insulating substrate 1,
After thoroughly washing this with a detergent, pure water and an organic solvent (FIG. 6A), electrodes 2 and 3 were formed on the surface of the insulating substrate 1 by a vacuum deposition technique and a photolithography technique.

Any material may be used as the material of the electrode as long as it has conductivity, but nickel metal was used in this embodiment. The electrode interval L1 was 2 μm, the electrode length W1 was 300 μm, and the electrode film thickness d was 1000 Å.

(Detailed Preparation Method) Resist Material RD-20
00N spin coater at 2500 rpm for 40 seconds 8
It was prebaked by heating at 0 ° C. for 25 minutes (FIG. 6 (b)).

Contact exposure is performed using an electrode-shaped mask and R
It was developed with a developing solution for D-2000N (FIG. 6 (c)). Then, it was post-baked by heating at 120 ° C. for 20 minutes.

Using a resistance heating vapor deposition machine, nickel was applied at a rate of 3 per second.
It was vapor-deposited with Å until the film thickness became 1000 Å (Fig. 6
(D)).

Lifted off with acetone, washed with acetone, inpropyl alcohol, and then with butyl acetate, and dried (FIG. 6 (e)).

2) Next, as shown in FIG. 7, a tape or a resist film or a chrome layer is provided at a place where it is not desired to disperse the fine particles, and then organic palladium (CCP-4230 manufactured by Okuno Chemical Industries Co., Ltd.) is applied by a spinner method. After coating, a tape or resist film is peeled off to form a fine particle film at a predetermined position and then baked at 300 ° C. for 1 hour to obtain palladium oxide (PdO) fine particles (particle diameter: 10Å to 150Å)
A fine particle film 4 mainly composed of was formed. Then, the fine particle film 4 was heated to about 200 ° C. in a reducing atmosphere (mixed gas of hydrogen gas and nitrogen gas) to form a fine particle film of palladium (Pd) fine particles (particle diameter: 8Å to 120Å, average particle diameter 20Å).

The particle size of the fine particles of palladium and palladium oxide is not limited to this. The width of the fine particle film 4 may be any value, but in this embodiment, it is 1 m.
m. Also, the thickness of the fine particle film 4 is from several tens of Å to 200 Å
Is practical, but not limited to this.

Next, chromium was deposited on the entire surface of the substrate to a thickness of 500 Å (FIG. 7 (f)).

The resist material AZ1370 is set to 2500 rp
m, 30 seconds spinner coating, 90 degreeC, 30 minutes heating and prebaking (FIG.7 (g)).

Exposure is performed using a mask having a pattern for applying an electron source material (FIG. 7 (h)), and a developing solution MIF31 is used.
2 was developed (FIG. 8 (i)). After that, 120 ℃, 30
It was heated for a minute and post-baked.

(NH ₄ ) Ce (NO ₃ ) ₆ / HCIO ₄
/ H ₂ O = 17 g / 5 cc / 100 cc was immersed in a solution for 30 seconds to etch chromium. (Fig. 8
(J)). The resist was peeled off by ultrasonically stirring in acetone for 10 minutes. (FIG. 8 (k)). ccp4230 (Okuno Pharmaceutical Co., Ltd.) was applied at 800 rpm for 30 seconds by a spinner and baked at 300 ° C. for 1 hour to obtain palladium oxide (Pd).
O) A thin film 4 for forming an electron-emitting portion, which is mainly composed of fine particles (particle diameter: 10Å to 150Å), was formed. (FIG. 8 (l)).

Subsequently, chromium was lifted off (see FIG. 9).
(M)).

3) Next, as shown in FIG. 9, when a voltage was applied between the electrodes 2 and 3 of the device to carry out an energization process, the electron-emitting portion 5 was formed at the site of the electron-emitting portion forming thin film 4. Could be formed. A fine particle film (particle size: 8Å to 120Å, average particle size 20Å) of fine particles of palladium (Pd) is formed by the energization treatment, and this is considered to be the electron emitting portion 3 (FIG. 9).
(N)).

Then, gallium chloride was EB vapor-deposited on the same sample in a vacuum. The deposition rate of FEP is about 3.0Å / se
In step c, 150 Å of thickness was mask-deposited near the electron emission portion.

This sample was exposed to the atmosphere of the atmosphere having a temperature of 30 ° C. and a humidity of 70% RH and then evacuated to a vacuum of 1 × 10 ⁻⁶ Torr, and the lead electrode was separated from the device by 5 mm in the vertical direction of the substrate. The emission current was measured at the position set and the applied voltage of 15 V between the electrodes 22 and 23 in FIG.

As a result, stable electron emission with an average emission current of 0.7 μA and emission current stability of ± 9% was obtained. In addition, the uniformity between the devices was good, the characteristic variation was 6 to 15%, and the emission efficiency at the time of electron emission (emission current / inter-electrode current) was as high as 1 × 10 ⁻⁴ . Further, it was possible to operate the electron emission repeating life for 100 hours or more.

It was confirmed by the analysis means such as SIMS, ESCA and EPMA that the surface was covered with the typical element.

Comparative Example 1 A sample was prepared and evaluated in the same manner as in Example 1 except that gallium chloride was not vapor-deposited in Example 1.

As a result, the average emission current was 0.8 μA and the stability of the emission current was ± 34%, and stable electron emission could not be obtained. Moreover, the variation in the characteristics between the elements is 19
The emission efficiency (emission current / inter-electrode current) during electron emission was 2 × 10 ⁻⁶ .
Further, the repeated life of electron emission was 79 hours.

Example 2 In Example 1, germanium hydride was dissolved in toluene / MEK = 1: 1 in place of vapor-depositing gallium chloride, and the solution was applied by spin coating and dried at 70 ° C. for 15 minutes. Was done.

This sample was evaluated in the same manner as in Example 1. As a result, the average emission current was 0.9 μA and the emission current stability was ± 12.
% Stable electron emission was obtained. Further, the uniformity between the devices was good, the variation in the characteristics was 8 to 17%, and the emission efficiency at the time of electron emission (emission current / interelectrode current) was as high as 8 × 10 ⁻⁵ . Furthermore, the repeated life of electron emission is 10
The operation for 0 hours or more was possible.

Example 3 In the structure as shown in FIG. 1, the element shape was W = 5.
A surface conduction electron-emitting device with mm and L = 2 μm was prepared as follows.

A gas deposition method widely known as a method for forming ultrafine particles ("Powder and Industry", Vo 1.19, N
No. 5, 1987), the thin film 4 was formed of silver fine particles having a particle diameter of 0.1 μm or less.

In the gas deposition method, the particle size is 0.1 μm.
It is possible to form a film with the following extremely small particles, and as the material, various metal materials such as gold, copper and nickel can be used in addition to silver. The width of the thin film 4 (in the direction parallel to the gap between the electrodes) was 2 mm.

Next, at a vacuum degree of 1 × 10 ⁻⁶ torr, a voltage is applied to the electrodes 5 and 6 at a voltage boosting rate of 1 V / 100 seconds, and the thin film 4 between the electrodes 5 and 6 is subjected to an electric heating treatment. The electron emitting portion 3 was formed.

Subsequently, indium was deposited on the same sample by sputtering to have a film thickness of 100 Å. The obtained sample was evaluated in the same manner as in Example 1, and as a result, the average emission current was 1.1 μA,
Stable electron emission with emission current stability of ± 14% was obtained. Also, the uniformity between the elements is good, and the variation in characteristics is 8 to 19
%, And the emission efficiency at the time of electron emission (emission current / inter-electrode current) was as high as 9 × 10 ⁻⁵ . Further, it was possible to operate the electron emission repeating life for 100 hours or more.

Example 4 In Example 3, instead of sputtering indium, selenized-p-tolyl was replaced with MEK / cyclohexane.
Dissolve 2: 1 and apply by spin coating,
It was dried at ℃ for 15 minutes.

The koko sample was evaluated in the same manner as in Example 1. As a result, the average emission current was 0.9 μA and the emission current stability was ± 16.
% Stable electron emission was obtained. In addition, the uniformity between the devices was good, the characteristic variation was 5 to 14%, and the emission efficiency at the time of electron emission (emission current / interelectrode current) was as high as 1 × 10 ⁻⁴ . Furthermore, the repeated life of electron emission is 10
Operation for 0 hours or more is possible.

Example 5 A surface conduction electron-emitting device having the structure shown in FIG. 1 was prepared as follows. Element shape is W1 = 200μ
m and L1 = 2 μm.

As the fine particle dispersion liquid, the following material was stirred together with glass beads for 24 hours with a paint shaker.

Fine particles SnO ₂ (particle size 1000 Å or less) 1.0 g Organic dispersion medium Methyl ethyl ketone: cyclohexane = 3: 1 800 cc First, on a white plate glass substrate 1 that has been sufficiently degreased and washed, a nickel film was formed by a vacuum film forming process and a photolithography process. The electrodes 5 and 6 were provided.

Next, the fine particle dispersion liquid was applied onto the substrate 1 by a spin coating method and baked at 250 ° C. for 10 minutes repeatedly to form a thin film 4 containing fine particles and having an electric resistance of 150 Ω or less.

After that, at a vacuum degree of 1 × 10 ^-6 torr, a voltage is applied to the electrodes 5 and 6 at a voltage boosting rate of 1 V / 100 seconds, and the thin film 4 between the electrodes 5 and 6 is subjected to an electric heating treatment to generate electrons. The emission part 3 was formed. Next, bismuth bromide was EB vapor-deposited on the same sample as in Example 1.

This sample was evaluated in the same manner as in Example 1. As a result, the average emission current was 1.3 μA and the emission current stability was ± 15.
% Stable electron emission was obtained. Further, the uniformity between the devices was good, the variation in the characteristics was 4 to 14%, and the emission efficiency at the time of electron emission (emission current / interelectrode current) was as high as 7 × 10 ⁻⁵ . Furthermore, the repeated life of electron emission is 10
The operation for 0 hours or more was possible.

Example 6 (XY Matrix) Next, an XY matrix using the electron-emitting device of the present invention will be described with reference to FIG.

After fixing the substrate 101 on which the electron-emitting device was manufactured as in Example 1 onto the rear plate 102,
The face plate 110 is placed 5 mm above the substrate 101.
(A fluorescent film 108 and a metal back 109 are formed on the inner surface of the glass substrate 107) are arranged via a support frame 103, and the face plate 110, the support frame 103,
Fluorite glass is applied to the joint portion of the rear plate 102, and the temperature is 400 ° C. to 50 ° C. in the air or nitrogen atmosphere.
It was sealed by baking at 0 ° C. for 10 minutes or more (see FIG. 12).

Further, the substrate 101 on the rear plate 102
Was also fixed with frit glass. In FIG.
104 is an electron-emitting device, and 105 and 106 are wiring electrodes in the X and Y directions, respectively. In this embodiment, as described above, the face plate 110, the support frame 103, and the rear plate 102 constitute the envelope 111. However, the rear plate 102 is provided mainly for the purpose of reinforcing the strength of the substrate 101. If it has sufficient strength by itself, the separate rear plate 102 is unnecessary, and the support frame 103 is directly sealed to the substrate 101, and the face plate 110,
The envelope 111 may be configured by the support frame 103 and the substrate 101.

The fluorescent film 108 is composed of only the phosphor in the case of monochrome, but in the case of the color fluorescent film, it is composed of a black conductive material called a black stripe or a black matrix depending on the arrangement of the phosphor and the phosphor. To be done. The purpose of providing the black stripe and the book matrix is to make the color mixture and the like inconspicuous by making the portions of the three primary color phosphors, which are necessary for color display, between the respective phosphors 113 black, and to make the phosphor film 108 inconspicuous. This is to suppress a decrease in contrast due to reflection of external light. In this embodiment, the fluorescent material has a stripe shape, a black stripe is first formed, and the fluorescent material of each color is applied to the gap portion to form the fluorescent film 108. A material containing graphite as a main component, which is often used as a material for black stripes, was used, but the material is not limited to this as long as it is electrically conductive and has little light transmission and reflection.

As a method of applying the phosphor to the glass substrate 107, a precipitation method or a printing method is used in the case of monochrome, but a slurry method is used in the present embodiment of color.
Even in the case of color, the same coating film can be obtained by using the printing method. A metal back 109 is usually provided on the inner surface side of the fluorescent film 108. The purpose of the metal back is to improve the brightness by specularly reflecting the light toward the inner surface side of the light emission of the phosphor to the face plate 110 side, to act as an electrode for applying an electron beam accelerating voltage, and This is to protect the phosphor from damage due to collision of negative ions generated in the enclosure. The metal back was produced by performing a smoothing treatment (usually called filming) on the inner surface of the fluorescent film after producing the fluorescent film, and then vacuum depositing A1.

The face plate 110 may be provided with a transparent electrode (not shown) on the outer surface side of the fluorescent film 108 in order to further enhance the conductivity of the fluorescent film 108. However, in this embodiment, only a metal back is provided. Since sufficient conductivity was obtained with, it was omitted. In the case of the above-mentioned sealing, in the case of a color, since the phosphors of the respective colors and the electron-emitting devices have to correspond to each other, sufficient alignment is performed.

Finally, the envelope thus completed is welded by heating an exhaust pipe (not shown) with a gas burner at a vacuum degree of about 1 × 10 ^-6 Torr to seal the envelope. went. Finally, a getter process was performed in order to maintain the degree of vacuum after sealing. Immediately before or after sealing, a getter arranged at a predetermined position (not shown) in the image display device is heated by a heating method such as resistance heating or high frequency heating to form a vapor deposition film. Processing. The getter usually has Ba or the like as a main component, and maintains the degree of vacuum by the adsorption action of the vapor deposition film.

In the image forming apparatus of the present invention completed as described above, each electron-emitting device is caused to emit electrons by applying a voltage through the terminals Dxl to Dxm and Dyl to Dyn outside the container. , A few k on the metal back 109 or transparent electrode (not shown) through the high voltage terminal Hv.
A high voltage of V or more is applied to accelerate the electron beam, and the fluorescent film 1
The image was displayed by colliding with 08 and exciting and emitting light.

The above-described structure is a schematic structure for manufacturing the image forming apparatus. For example, the detailed parts such as the material of each member are not limited to the contents described above, and further, a plurality of electron-emitting devices. The arrangement form of the substrate 104 on the substrate 101 may be a form in which a plurality of element rows in which a plurality of electron-emitting devices are connected between a pair of wiring electrodes are arranged, and in this case, the element rows are orthogonal to each other. A control electrode (normally referred to as a grid) for selecting an element that causes the phosphor to emit light is arranged in the direction. Thus, the selection is appropriately made to suit the application of the image forming apparatus.

[0121]

As described above, in the electron-emitting device of the present invention, the electron-emitting portion is covered with an element of the typical element or the compound of the typical element, which is chemically stable and can be coated on the surface. It is possible to reduce fluctuations in electron emission efficiency and variations in characteristics, which are considered to be due to the above.

Further, it has become possible to provide a stable electron-emitting device having a long life. Further, as shown in FIG. 11, according to the ligand field, the electron emission efficiency was also improved due to the splitting of the d orbital.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of a basic electron-emitting device according to the present invention.

FIG. 2 is a process drawing showing an example of a method for manufacturing an electron-emitting device.

FIG. 3 is a schematic configuration diagram of a measurement / evaluation apparatus for measuring electron emission characteristics of an element.

FIG. 4 is a schematic diagram showing a configuration of an electron-emitting device of the present invention.

FIG. 5 is a schematic diagram showing a structure of an electron-emitting device of the present invention.

FIG. 6 is a process drawing showing the process of the first part of the method of manufacturing an electron-emitting device.

FIG. 7 is a process drawing showing a process of the second part of the method for manufacturing the electron-emitting device.

FIG. 8 is a process drawing showing the process of the third portion of the method of manufacturing the electron-emitting device.

FIG. 9 is a process drawing that shows the process of the fourth portion of the method of manufacturing the electron-emitting device.

FIG. 10 is a diagram showing a general configuration of an SCE element.

FIG. 11 is a diagram showing energy levels of d orbit.

FIG. 12 is a schematic configuration diagram showing a configuration of a simple matrix display panel.

[Explanation of symbols] 1 insulating substrate 2 thin film for forming electron emitting portion 3 electron emitting portion 4 thin film including electron emitting portion 5,6 element electrode 7,9 matrix electrode 11 typical element or typical element compound 22,23 electrode 24 Cr 25 Resist 30,32 Ammeter 31 Power Supply 33 High Voltage Power Supply 34 Anode Electrode

Claims (9)

[Claims] 1. An electron-emitting device in which a transition element and / or a transition element compound is sandwiched between a pair of electrodes and a voltage is applied between the electrodes to emit electrons, wherein the transition element and / or the transition element are II of the periodic table on the surface of the compound
An electron-emitting device characterized by being coated with a typical element belonging to Group I or a typical element compound. 2. An electron-emitting device in which a transition element and / or a transition element compound is sandwiched between a pair of electrodes and a voltage is applied between the electrodes to emit electrons, wherein the transition element and / or the transition element are IV of the periodic table on the surface of the compound
An electron-emitting device characterized by being coated with a typical element or a typical element compound belonging to the 4th, 5th and 6th periods of the group. 3. An electron-emitting device in which a transition element and / or a transition element compound is sandwiched between a pair of electrodes and a voltage is applied between the electrodes to emit electrons, wherein the transition element and / or the transition element An electron-emitting device characterized in that the surface of the compound is coated with a typical element or a compound of a typical element belonging to Group V fourth, fifth and sixth periods of the periodic table. 4. An electron-emitting device in which a transition element and / or a transition element compound is sandwiched between a pair of electrodes and a voltage is applied between the electrodes to emit electrons, wherein the transition element and / or the transition element are VI of the periodic table on the surface of the compound
An electron-emitting device characterized by being coated with a typical element or a typical element compound belonging to the 4th, 5th and 6th periods of the group. 5. A voltage (V) higher than the first ionization potential or work function (eV) of the transition element and / or the transition element compound is provided between a pair of electrodes sandwiching the transition element and / or the transition element compound. The electron-emitting device according to any one of claims 1 to 4, wherein the electron-emitting device emits electrons when applied. 6. An image forming apparatus comprising the electron-emitting device according to claim 1 and a phosphor. 7. An image forming apparatus comprising a plurality of electron-emitting devices according to any one of claims 1 to 5, which are electrically connected to wiring electrodes and arranged, and a phosphor. 8. A typical element according to claim 1 or 4, wherein a transition element and / or a transition element compound is provided between a pair of electrodes, and the transition element and / or the transition element compound is in a gaseous state in vacuum. A method for manufacturing an electron-emitting device, which comprises reacting a typical element compound. 9. A recording method for recording on a recording medium using emitted electrons from the electron-emitting device according to claim 1 or fluorescence or phosphorescence due to the emitted electrons.