JP2003086084A - Method of manufacturing electron emission element, image forming device, apparatus of manufacturing image forming device, and method of manufacturing image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method or an electron emission element with less uneven brightness, an image forming device and its manufacturing device and its manufacturing method. SOLUTION: The manufacturing method of the electron emission element with less uneven brightness comprises the steps of forming a cathode electrode 20 on the surface of a substrate 12; forming a fibrous carbon 22 emitting electrons on the surface of the cathode electrode by applying a voltage across the cathode electrode and an anode electrode 15 in image forming operation; and producing discharge so that energy produced in the fibrous carbon 22 and consumed by one discharge is less than the maximum value of static energy stored between the cathode electrode 22 and the anode electrode 15 in the image forming operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an electron-emitting device, an image forming apparatus used in a television broadcast, a television conference system, a computer, etc., which uses the electron-emitting device manufactured by the manufacturing method. The present invention relates to a manufacturing apparatus and a manufacturing method for the image forming apparatus.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for a thin flat panel display device as a display device, and a display device using liquid crystal is a conventional CRT.
Is replacing and becoming popular. However, since liquid crystal does not emit light by itself and requires a backlight or the like, realization of a self-luminous display device has been desired.

An element that applies a strong electric field of 10 ⁶ V / cm or more to a metal to emit electrons from the metal surface is called a field emission type (FE type) electron emitting element. The FE-type cold electron source is particularly attracting attention because it can constitute the above-described thin and self-luminous image display device if it is put into practical use, and it can be expected to reduce power consumption and weight.

As an example of a vertical FE type electron-emitting device, a cathode electrode 33a has a conical shape in a substantially vertical direction from a substrate 30 as shown in a horizontal cross section of FIG. Spindt, "Physical Properties of t
hin-film field emission cathodes with molybdenum c
Ones ", J. Appl. Phys., 47, 5248 (1976) and the like (hereinafter, Spindt type) are known.

An insulating layer 31 and a gate electrode 32a are formed on a substrate 30, and a conical cathode electrode 33a made of Mo or the like is formed inside a hole obtained by fine processing. Further, the anode electrode and the phosphor 35 are formed on the surface of the face plate 34 which is arranged so as to face the gate electrode 32a.

When a voltage is applied to the minute gap between the cathode electrode 33a and the gate electrode 32a, electrons are field-emitted from the vicinity of the tip of the cone where the electric field is concentrated. A high voltage is applied between the anode electrode 35 and the cathode electrode 33a, and the electrons extracted from the cathode electrode 33a are accelerated and then collide with the anode electrode and the phosphor 35 to generate fluorescence.

Further, as an example of a laterally configured element,
As shown in the cross section of FIG. 6B, a cathode electrode 33b having a sharpened tip and a gate electrode 32b for drawing electrons from the cathode electrode tip are formed in parallel with the substrate 30,
It is known that the anode electrode 35 is formed in a direction perpendicular to the direction in which the gate electrode 32b and the cathode electrode 33b face each other, for example, those disclosed in USP 4728851 and USP 4904895.

An insulating layer 31, a gate electrode 32b and a cathode electrode 33b are formed on the substrate 30 as shown. Here, the tip of the cathode electrode 33b is sharply processed into a needle shape or a comb shape by fine processing. The anode electrode and the fluorescent substance 35 are formed on the surface of the face plate 34 arranged to face the gate electrode 32b, as in the Spindt type.

When a voltage is applied between the cathode electrode 33b and the gate electrode 32b, electrons are field-emitted from the vicinity of the emitter tip where the electric field is concentrated. A high voltage is applied between the anode electrode 35 and the cathode electrode 33b, and the electrons extracted from the cathode electrode 33b are accelerated upward and then collide with the anode electrode and the phosphor 35 to generate fluorescence. In addition, some of the extracted electrons are scattered on the surface of the gate electrode and are then drawn upward, which contributes to light emission.

The device described above utilizes electron field emission from the tip of the sharpened metal electrode. However, it is difficult to obtain a large number of elements per pixel of an image display device with an element formed by microfabrication, and the strength of the electric field required for field emission is also large. Therefore, the use of carbon nanotubes as an emitter material, which has a high density of electron emission points and is capable of emitting electrons with a low electric field intensity, has been studied.

That is, attempts have been made to construct an emitter with a known carbon nanotube (hereinafter referred to as CNT) or to coat the surface of a cathode electrode (structure) with a thin film of carbon nanotube. These carbon nanotubes are extremely thin with a diameter of several to several tens nm, and thus have a high aspect ratio. It is thought that the tip of the carbon nanotube is the electron emission point, but the number is much larger than that of the Spindt-type emitter.

As an example of an electron-emitting device using carbon nanotubes, there is disclosed a structure in which an organic compound gas is used for thermal decomposition on a fine catalytic metal to deposit carbon nanotubes. In addition, there is a method of growing in a plasma atmosphere, or a method of forming carbon nanotubes previously produced and purified by another device into a paste using a solvent and applying the same to the electrode surface by printing or the like, followed by baking. Are known.

FIG. 7 (a) is an enlarged cross-sectional view of the emitter portion produced by the above method. Carbon nanotubes
It is known to take various shapes depending on the metal (alloy) used as a catalyst, the material gas, the growth method and the conditions. A cathode electrode 20 as a base and a catalytic metal layer 21 are sequentially formed on a substrate 12, and carbon nanotubes 36a are grown on the catalytic metal layer. Horizontal FE
FIG. 8 shows an example of the display panel portion of the image forming apparatus configured by using the electron-emitting device. 41 is a substrate on which a plurality of electron-emitting devices 44 are arranged, 51 is a rear plate to which the substrate 41 is fixed, 56 is a face plate in which a phosphor film 54 and a metal back 55 are formed on the inner surface of a glass substrate 53, 5
2 is a support frame.

The display panel 40 is constructed by sealing the rear plate 51, the support frame 52 and the face plate 56 with frit glass or the like. Display panel 4
The inside of 0 is vacuumed at the time of sealing or after sealing, and the degree of vacuum is maintained by a getter (not shown) during operation.

42 and 43 are electron-emitting devices 4 respectively.
4 are the X-direction and Y-direction wirings connected to the cathode electrode or the gate electrode of FIG.
oxm, Dyo1 to Dyon are provided outside the support frame 52. By applying a voltage between the X-direction wiring 42 and the Y-direction wiring 43, electrons are emitted from the corresponding electron-emitting devices 44.

A high voltage electrode 58 is connected to the metal back 55 on the inner surface of the phosphor film 54, and acts as an electrode for accelerating the electrons emitted from the device by applying a high voltage between the metal back 55 and the cathode electrode. To do.

[0017]

When carbon nanotubes are formed on the cathode electrode on the substrate, the surface thereof is not always uniform, and the tips of the carbon nanotubes are projected in places. In addition, the degree and frequency of protrusion also differ in each cathode electrode in many cases. This is because it is technically difficult to make the various conditions during formation uniform over the entire surface of the substrate as the surface of the thin film of extremely fine carbon nanotubes is made flat.

Electrons are more likely to be emitted from the protruding tip of the carbon nanotube as compared with other portions due to the effect of electric field concentration. The nonuniformity of the degree and frequency of protrusion leads to nonuniformity of the electron emission characteristics of the device, which is a major cause of uneven brightness when the image forming apparatus is constructed.

Further, discharge is likely to occur from the above-mentioned protruding portion, which may damage the element and thus the image forming apparatus. The situation is shown in FIG. Carbon nanotubes 22 are formed on the cathode electrode 20 and the catalytic metal layer 21 on the substrate 12. Further, the anode electrode 3 is provided at a position facing the substrate 12 and separated by a distance D _0.
5 and the face plate 34 are arranged. A voltage for accelerating electrons is applied between the anode electrode 35 and the cathode electrode 20.

Electrons e ⁻ are easily emitted from the protruding portions 22a of the carbon nanotubes where the electric field is concentrated. These electrons are accelerated and collide with gas (molecules) in the atmosphere,
The electron e ⁻ is knocked out by a so-called ionization action and a new ion M ⁺ is generated. After being accelerated, it may collide with the anode electrode and knock out another electron (secondary electron) or adsorbed molecule.

Further, the ions M ⁺ in the atmosphere are attracted to and collide with the vicinity of the projection 22a where the electric field is concentrated while being accelerated, and knock out electrons and adsorbed gas molecules from the cathode electrode. If the applied voltage is sufficient, the avalanche phenomenon that follows these phenomena causes a spark 23 between itself and the anode electrode, resulting in discharge. Although the anode electrode has been described here as an example, discharge may occur between the anode electrode and the gate electrode to which the extraction voltage is similarly applied.

At the time of discharging, the electric charge Q ₀ accumulated between the electrodes facing each other instantaneously moves through the spark 23, so that a large current flows through the protrusion 22a. Further, the ions M + in the accelerated atmosphere are attracted to and collide with the vicinity of the protrusion 22a where the electric field is concentrated. As a result, as shown in FIG. 9, the element is damaged such that the carbon nanotubes in the vicinity of the protruding portion are scraped (22c) or the underlying electrodes are destroyed (22d).

The former lowers the electron emission efficiency, and the latter causes malfunction of not only the element but also the entire scanning line to which the element belongs. That is, when the element 44 in FIG. 8 is damaged, the Doy (n-
1) It is possible that all the elements connected to the line will not emit light. Although not shown in the figure, the anode or the gate electrode side is also similarly damaged by the current flowing instantaneously and the colliding electron e-.

Therefore, in order to make the electron emission characteristics of each element uniform, a method of cutting off the protruding portion with a laser beam or a heated blade-shaped object (Japanese Patent Laid-Open No. 2000-22300).
5) is proposed. If the surface of the carbon nanotube film is made physically flat, the breakdown due to discharge is reduced, and the electron emission characteristics can be expected to be uniform. On the other hand, in these methods, positioning is difficult and shavings that affect the electron emission characteristics may occur.

Further, the electron emission characteristics of individual carbon nanotubes depend on the crystallinity and orientation, the density of carbon nanotubes, the average height of the surface, and the like. Non-uniformity remains in the emission characteristics. For this reason, there is still room for further improvement in terms of easiness of implementation and the principle.

The present invention has been made in order to solve the above-mentioned problems of the prior art, and an object thereof is to use an electron-emitting device in which individual characteristics are made uniform by using fibrous carbon such as carbon nanotubes, and An object of the present invention is to provide an image forming apparatus using the electron-emitting device without uneven brightness, and to provide a simple manufacturing apparatus and manufacturing method for preventing performance deterioration of the image forming apparatus.

[0027]

In order to achieve the above object, in the method of manufacturing an electron-emitting device of the present invention, a step of forming a cathode electrode on the surface of a substrate and a step of forming the cathode electrode on the surface of the cathode electrode are performed. A step of forming fibrous carbon that emits electrons by a voltage applied between the cathode and an anode electrode or a gate electrode provided opposite to the cathode electrode during driving; Causing discharge so that the energy consumed by the discharge becomes less than the maximum value of electrostatic energy accumulated between the cathode electrode and the anode electrode during driving. .

The fibrous carbon is preferably composed of carbon nanotubes, graphite nanofibers, amorphous carbon or a mixture thereof.

Further, in the image forming apparatus of the present invention,
A first substrate having at least one row in which a plurality of electron-emitting devices manufactured by the manufacturing method are arranged in parallel and connected to each other, and the first substrate is opposed to the first substrate at a predetermined distance. And a second substrate having an anode electrode formed on a surface facing the first substrate.

Further, in the method for manufacturing an image forming apparatus of the present invention, a chamber in which the first substrate of the image forming apparatus can be put in and taken out, and the outer periphery of the first substrate is enclosed inside the chamber. An envelope provided with wiring for electrically connecting to the wiring of the first substrate, and an electrode arranged on the surface facing the surface of the first substrate and facing the surface of the first substrate. An electric field applying mechanism having, and applying a voltage between the wiring provided in the envelope and the electrode having the electric field applying mechanism, the fibrous carbon and the electrode having the electric field applying mechanism. It is characterized in that a discharge is generated between them.

When a voltage is applied between the wiring of the envelope and the electrode of the electric field applying mechanism, the first
It is preferable that the distance between the substrate surface and the electrode of the electric field applying mechanism is set to be narrower than the distance between the cathode electrode and the anode electrode in the image forming apparatus.

It is preferable that the electric field applying mechanism has, as an electrode, a planar conductor arranged in parallel with the surface of the first substrate.

The planar conductor is substantially rectangular, and its longitudinal direction may be different from the longitudinal direction of the wiring to which the cathode electrode of the electron-emitting device formed on the opposing first substrate is connected. It is suitable.

It is preferable that the electric field applying mechanism has a conductor wire arranged in parallel with the surface of the first substrate as an electrode.

It is preferable that the electric field applying mechanism has, as an electrode, a thin plate having a linear tip and having the linear tip arranged on a plane parallel to the surface of the first substrate.

It is preferable that the electric field applying mechanism is capable of moving the electrode of the electrolysis applying mechanism in parallel with the surface of the first substrate while keeping a constant gap.

Further, in the method of manufacturing the image forming apparatus of the present invention, a part of the electron emitting portion of the fibrous carbon formed on the surface of the cathode electrode disappears using the manufacturing apparatus of the image forming apparatus. And a step of exposing a new electron emission portion.

The step of eliminating a part of the electron emitting portion of the fibrous carbon formed on the surface of the cathode electrode and exposing a new electron emitting portion is performed by the wiring provided in the envelope and the electric field application. A voltage is applied between the mechanism and the electrode, and the electron emission current from the electron emission element is detected.
It is preferable to terminate the process when the electron emission current reaches a predetermined value.

The voltage applied between the wiring provided in the envelope and the electrode of the electric field applying mechanism is preferably applied in a pulsed manner.

[0040]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be illustratively described in detail below with reference to the drawings. However, the dimensions of the components described in this embodiment,
Unless otherwise specified, the material, the shape, the relative arrangement, and the like are not intended to limit the scope of the present invention thereto. Further, the materials, shapes, and the like of the members once described in the following description are the same as those in the first description unless otherwise specified.

FIG. 1 is a side sectional view of an image forming apparatus manufacturing apparatus according to this embodiment. Reference numeral 10 is a chamber, 11 is a substrate support, and 12 is a substrate, on the surface of which wiring (not shown) is provided and electron-emitting devices are formed. Reference numeral 13 denotes an envelope, which is tightly fixed around the substrate 12. The envelope 13 is provided with an electrode in a contact portion with the substrate 12, and is electrically connected to the wiring of the substrate 12.

Reference numeral 17 denotes an electric field applying mechanism, which is a support member 16,
It is composed of a conductor portion 15 and a spacer 14. The conductor portion 15 is arranged so as to face the substrate 12, and the distance D is defined by the spacer 14 slightly protruding from the surface of the conductor portion 15. 18 is an exhaust pipe, 19
Is an introduction pipe through which the chamber 10 can be exhausted and the atmosphere can be opened.

In the present embodiment, fibrous carbon is treated in the following procedure to achieve uniform emission characteristics among devices and prevention of discharge.

First, the substrate 12 on the surface of which electron-emitting devices are formed and wiring is completed is carried into the chamber 10 and placed on the substrate support 11. Then, the envelope 13 is closely arranged around the substrate 12 and electrically connected to the electrodes on the substrate. The electric field applying mechanism 17 is brought close to the substrate 12 from above, and the spacer 14 is abutted against the envelope 13 so that the conductor portion 15 and the substrate 12
Interval D is determined. Further, the inside of the chamber is evacuated to a desired pressure.

FIG. 2 is a cross-sectional view of an essential part showing a state of discharge processing of the electron-emitting device according to this embodiment. In the above state, a voltage is applied between the cathode electrode 20 and the conductor portion 15 to cause a discharge between the conductor portion 15 and the fibrous carbon formed on the cathode electrode of the electron-emitting device. Figure 2
FIG. 2A is a cross-sectional view of the main part, showing the state during discharge and FIG. 2B showing the state after the discharge treatment. A cathode electrode 20, a catalytic metal layer 21, and a fibrous carbon 22 are sequentially formed on the surface of the substrate 12, and a conductor portion 15a is formed on the support 16 of an electric field applying mechanism (not shown).

The fibrous carbon in the present invention means "fibrous carbon" or "columnar material containing carbon as a main component".
Alternatively, it can be referred to as "a linear substance containing carbon as a main component". The "fibrous carbon" can also be referred to as "fiber containing carbon as a main component". and again,
The "fibrous carbon" in the present invention is more specifically,
Carbon nanotube, graphite nanofiber,
Includes amorphous carbon fiber. Of these, graphite nanofibers are the most preferable.

The "graphite nanofiber" is composed of a laminated body of graphene. More specifically, graphite nanofiber refers to a fibrous substance in which graphene is laminated in the longitudinal direction (axial direction of the fiber). In other words, graphene is a fibrous material arranged non-parallel to the fiber axis.

Further, the carbon nanotube is a fibrous substance in which graphene is arranged so as to surround the longitudinal direction (axial direction of the fiber) (cylindrical shape). In other words, graphene is a fibrous material arranged substantially parallel to the fiber axis.

Alternatively, the carbon nanotube refers to one in which graphene has a cylindrical shape (a cylinder having a multiple structure is called a multi-wall nanotube). In particular, the carbon nanotube has the lowest electron emission threshold when the tube tip is open.

One surface of graphite is called "graphene" or "graphene sheet". More specifically, graphite is made by stacking carbon planes arranged so as to spread regular hexagons formed by covalent bonds by sp ² hybridization with a distance of 3.354Å. . This carbon plane is "graphene"
Alternatively, it is called a “graphene sheet”.

Both fibrous carbons have an electron emission threshold value of about 1 V to 10 V / μm, and are preferable as the fibrous carbon of the present invention.

Further, FIG. 7B shows a schematic view when the graphite nanofibers 36b are arranged on the structure in which the cathode electrode 20 and the catalyst layer 21 arranged on the substrate 12 are laminated.

The spark 23 due to the discharge is composed of the conductor portion 15a and the fibrous carbon protrusion 22a, more precisely, the portion where the electric field is most concentrated and the electrons are emitted in the plane of the fibrous carbon on the cathode electrode. The protrusions are generated by the Joule heat or the ion bombardment and are selectively scraped off. By applying a predetermined voltage for an appropriate time, the protruding portions of the fibrous carbon 22 are sequentially scraped off, and finally, as shown in FIG.
More precisely, a fibrous carbon surface having uniform electron emission characteristics can be obtained.

Here, the conductor portion 15a is accumulated when a voltage is applied, as compared with the anode electrode of the image forming apparatus (that is, the metal back formed on the entire back surface of the face plate via the phosphor film). Formed so that the amount of electrostatic energy generated is small.

At the time of discharge, the electric charge Q stored between the electrodes becomes a current and concentrates on the projecting portion all at once to generate Joule heat, and also damage due to ion bombardment occurs. If the amount of stored electrostatic energy is large, not only the protruding portion but also the cathode electrode may be destroyed.

The distance D between the substrate 12 and the conductor portion 15a may be set shorter than the distance D ₀ (shown in FIG. 9) between the cathode electrode and the anode electrode when the image forming apparatus is actually constructed. It is desirable to reduce the damage during discharge. The electrostatic energy concentrated on the protrusions during discharge is C when the capacitance between the electrodes is C and the applied voltage is V.
And V ² are proportional to the product C · V ² .

Here, the standard of the applied voltage V, that is, the discharge start voltage is given by the product E · D of the electric field strength E at which the fibrous carbon begins to emit electrons and the interval D. While the capacitance C is inversely proportional to the distance D, the applied voltage V is proportional to the distance D. Therefore, it is effective to reduce the distance D to reduce the electrostatic energy stored.

By such discharge processing, the electron emission characteristics from the fibrous carbon in the elements are made uniform, and the electron emission characteristics of the elements are made uniform, so that an image forming apparatus with less uneven brightness can be constructed. Becomes Further, in the process of homogenization, the protrusions of fibrous carbon, which are more likely to emit electrons than the surroundings, are removed, so that it is possible to prevent discharge and subsequent destruction of the element when configured as an image forming apparatus. it can.

[0059]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

(Embodiment 1) FIG. 3 is a perspective view of a main part of a manufacturing apparatus in this embodiment. Reference numeral 12 is a substrate on the surface of which electron-emitting devices are arranged, 13 is an envelope, 42 is wiring in the X direction of the substrate 12, and 43 is wiring in the Y direction. The X-direction wiring 42 is connected to the cathode electrode of each element, and the Y-direction wiring is connected to the gate electrode. Reference numeral 17 denotes an electric field applying mechanism, and a conductor portion 15b is provided in a portion of the support 16 facing the substrate 12 so as to be parallel to the substrate 12. Conductor part 1
5b is subdivided and connected to the wiring 62.

The cross section taken along the line AA 'of FIG. 3 corresponds to the above-mentioned FIG. 1, but the substrate 12 and the electric field applying mechanism 17 are shown separated from each other in the vertical direction for easy understanding.

In the present embodiment, the conductor portion 15b is formed as an electrode on the surface (substrate side) of the flat plate. The plane plate is arranged parallel to the substrate 12 so as to face each other, and the distance D
Is accurately defined by a spacer (not shown). In addition, for example, each region of the conductor portion 15b subdivided into a plurality of striped or rectangular shapes is connected to one of the wirings 62 in a one-to-one correspondence.

Although the wiring 62 is arranged in the periphery in FIG. 3, a so-called via hole may be formed on the back surface (the side opposite to the substrate) of the conductor portion 15b to take out the wiring 62 from the back surface of the plane plate. .

When the desired element is subjected to the electric discharge treatment, it is placed between the X-direction wiring 42 connected to the cathode electrode of the element and the wiring 62 connected to the conductor portion 15b facing the element. Apply high voltage. For example, a negative voltage is applied to the X-direction wiring 42 connected to the cathode electrode of the desired element, and a positive voltage is applied to the wiring 62 of the conductor portion facing the desired element. Other X-direction wiring and Y-direction wiring,
The wiring 62 of the conductor portion is preferably grounded.

In order to reduce the electrostatic energy accumulated before the discharge, the total amount of charges accumulated between the electrodes may be reduced. For that purpose, it is effective to reduce the area of each conductor portion, that is, the area of the portion facing the cathode electrode when a voltage is applied. If the conductor portion is formed in a striped shape elongated in the Y direction and a voltage is applied between the conductor portion and the X-direction wiring 42 connected to the cathode electrode, not only the amount of electrostatic energy accumulated is reduced, but also It is possible to selectively perform the discharge process on the element or the element group at the intersection of the two wirings. After the processing is performed for a predetermined time, the wiring to which the voltage is applied is sequentially switched to perform the processing on all the elements.

Further, a configuration is possible in which a large number of elements are simultaneously processed, such as grounding all conductors and applying a negative voltage to the X-direction wiring 42 to which the cathode electrodes of the elements are connected. Although the overall configuration time can be shortened with an easy configuration, the amount of electrostatic energy accumulated before discharge increases, so the number of elements to be processed at a time and the applied voltage do not cause excessive damage to the elements due to discharge processing. You need to set it so that it does not exist.

As described above, the electron emission characteristics of the device can be made uniform over the entire surface of the substrate with a simple structure in which a voltage is applied between the device on the substrate and the electrodes formed on the parallel plate. Is.

(Embodiment 2) FIG. 4 shows a perspective view of a main part of a manufacturing apparatus in this embodiment. Reference numeral 12 is a substrate having an electron-emitting device arranged on its surface, 13 is an envelope, 42 is an X-direction wiring of the substrate 12, 43 is a Y-direction wiring, which are connected to the cathode electrode and the gate electrode of the electron-emitting device, respectively. . A conductor portion 15c is provided on a portion of the support 16a facing the substrate 12.
Are provided parallel to the substrate 12, that is, at equal intervals with the substrate. The support 16a is incorporated in an electric field applying mechanism (not shown), and moves in a plane 24 parallel to the substrate 12 while applying a voltage between the conductor portion 15c and an element on the substrate 12.

The conductor portion 15c is, for example, the Y-direction wiring 43.
It is a flat conductor in the shape of a striped strip along the line, and is arranged in parallel with the substrate 12 at a distance D, and a positive voltage is applied. By applying a negative voltage to the X-direction wiring 42,
A discharge process is performed between the conductor portion 15c on the substrate and the electron-emitting device formed in a portion facing the conductor portion 15c. After the processing is performed for a predetermined time, the X-direction wiring to which the negative voltage is applied is sequentially changed. After the processing of the elements facing the conductor portion 15c is completed, the conductor portion 15c is moved in parallel with respect to the substrate 12 and the same processing is sequentially performed, so that all the elements are processed.

As the conductor portion 15c, not only a flat electrode but also various ones can be used. FIG. 5 shows an enlarged view of one element in the BB ′ cross section of FIG. These are the cathode electrodes 20 of the device formed on the substrate 12.
The fibrous carbon 21 is subjected to electric discharge treatment by using the conductor portions 15 having various shapes.

In FIG. 5 (a), a metal wire is used as the conductor portion 15d, and as the conductor portion 15e in FIG. 5 (b), an elongated blade-shaped conductor whose one side is sharpened, such as a razor blade, is used. is doing. When a voltage is applied between the conductor portions 15d and 15e and the fibrous carbon 21, the electric field is concentrated on the fibrous carbon protrusions 22a, and sparks 23 are generated by the discharge to scrape off the protrusions.

By making the metal wire of FIG. 5 (a) and the blade of FIG. 5 (b) sufficiently thin or sharp,
An effect of reducing the total amount Q of electric charges accumulated by the discharge, and hence the amount of electrostatic energy, can be expected. This makes it possible to reduce the area of the portion facing the cathode electrode as compared with the case of a flat surface, and since the electric field concentrates on the portion having a large curvature such as the tip of the blade, electrons are emitted from the protrusion 22a at a lower applied voltage. Because it begins to be released.

Although only one set of the support 16a and the conductor portion 15c is shown in FIG. 4, a plurality of sets are prepared and the discharge treatment is performed while simultaneously moving in the plane 24 parallel to the substrate 12. May be. In the case of only one set, it is necessary to move the conductor part over the entire panel surface, but if a plurality of sets are prepared, the moving distance per one conductor part can be shortened, so that the time taken for the discharge treatment can be shortened. It is possible.

(Embodiment 3) In the present embodiment, the voltage applied to the element or the conductor portion during the discharge treatment is applied in a pulse form. Normally, when a voltage is applied to fibrous carbon, electron emission starts only when a certain threshold voltage is exceeded,
Furthermore, discharge occurs. Depending on the fibrous carbon, once a voltage is applied to start discharge, subsequent discharge may occur at short time intervals one after another. Then, the fibrous carbon is severely scraped, and it is difficult to make the electron emission characteristics of each device uniform by a method of continuously applying a constant voltage.

Therefore, one or both of the voltages applied to the element or the conductor portion are changed in a pulse shape. By properly selecting the time intervals at the high and low voltage levels, their ratio (duty ratio), and the waveform,
It becomes possible to appropriately control the speed at which the fibrous carbon is scraped.

Since it is generally relatively difficult to generate a pulse having a large voltage amplitude, a voltage that does not cause discharge to the device, for example, a voltage below the threshold voltage at which fibrous carbon emits electrons is usually used. Voltage is applied to the cathode,
When actually performing the discharge treatment, only the difference voltage may be applied to the anode.

(Embodiment 4) In this embodiment, the electron emission current from the cathode when a voltage is applied is used as a standard for ending the above-mentioned discharge treatment. Depending on the substrate, the fibrous carbon formed on the cathode electrode of the device has different shapes and densities at the positions, for example, the central part and the peripheral part, and also has different electron emission characteristics. Therefore, the electron emission characteristics may not be uniform even if the discharge treatment is performed for the same time.

Therefore, the electron emission current from the cathode is monitored when performing the discharge process, and the process is terminated when a predetermined current value is obtained. The current to be detected is suitable because it is easy to detect the anode current between the cathode and the anode (that is, the conductor portion of the electric field applying mechanism), but the gate current between the cathode and the gate may be detected. However, in the latter case, it is necessary to apply a voltage between the cathode and the gate at the time of detection to extract electrons. Further, the detection need not always be performed, and the discharge mode may be switched to the detection mode after the discharge processing is performed for a predetermined time or a predetermined number of times in the case of a pulse, and the electron emission current may be measured.

According to the present embodiment, even if the shape and characteristics of the fibrous carbon have some place dependence, the electron emission characteristics can be made uniform, and the uneven brightness in the image forming apparatus can be further reduced. It will be possible.

[0080]

As described above, according to the present invention, it is possible to obtain an electron-emitting device capable of obtaining stable electron emission and an image forming apparatus using the same, which has less unevenness in brightness and is less likely to be destroyed by discharge. .

Further, it is possible to obtain a manufacturing apparatus capable of easily producing the above-mentioned image forming apparatus and a manufacturing method using the manufacturing apparatus.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a manufacturing apparatus of an image forming apparatus according to this embodiment.

FIG. 2 is a main-portion cross-sectional view showing a state of discharge processing of the electron-emitting device according to the present embodiment.

FIG. 3 is a perspective view of a main part of the manufacturing apparatus according to the first embodiment.

FIG. 4 is a perspective view of a main part showing a manufacturing apparatus according to a second embodiment.

FIG. 5 is a sectional view of a manufacturing apparatus according to a second embodiment.

FIG. 6 is a cross-sectional view for explaining a conventional electron-emitting device.

FIG. 7 is a sectional view for explaining fibrous carbon formed on an electrode by a conventional method.

FIG. 8 is a perspective view of a main part for explaining a conventional image forming apparatus.

FIG. 9 is a diagram for explaining the influence of discharge on an electron-emitting device in a conventional image forming apparatus.

[Explanation of symbols]

10 chambers 11 Substrate support 12, 30, 41 substrate 13 envelope 14 Spacer 15 Conductor part 16 Support 17 Electric field application mechanism 18 Exhaust pipe 19 Introductory pipe 20, 33 cathode electrode 21, 36 catalytic metal layer 22 Fibrous carbon 23 sparks 24 Plane parallel to substrate 31 insulating layer 32 gate electrode 34, 56 Face plate 35 Anode electrode 42 X-direction wiring 43 Y direction wiring 44 electron-emitting device 51 rear plate 52 Support frame 53 glass substrate 54 Phosphor film 55 Metal back 58 High voltage electrode 62 wiring

Claims (13)

[Claims] 1. A step of forming a cathode electrode on a surface of a substrate, and applying on the surface of the cathode electrode between the cathode electrode and an anode electrode or a gate electrode provided to face the cathode electrode during driving. The energy consumed by one discharge generated in the fibrous carbon and the step of forming fibrous carbon that emits electrons by the applied voltage is accumulated between the cathode electrode and the anode electrode during driving. And a step of causing an electric discharge so that the electrostatic energy is less than the maximum value, the method of manufacturing an electron-emitting device. 2. The method of manufacturing an electron-emitting device according to claim 1, wherein the fibrous carbon is made of carbon nanotube, graphite nanofiber, amorphous carbon or a mixture thereof. 3. A first substrate having at least one or more device rows formed by arranging and connecting a plurality of electron-emitting devices manufactured by the manufacturing method according to claim 1 or 2,
An image forming apparatus, comprising: a second substrate that is arranged to face the first substrate at a predetermined distance, and has an anode electrode formed on a surface facing the first substrate. 4. An apparatus for manufacturing the image forming apparatus according to claim 3, wherein a chamber into which the first substrate of the image forming apparatus can be loaded and unloaded, and a first substrate inside the chamber. An envelope which is provided so as to surround the outer periphery and includes wiring for electrically connecting to the wiring of the first substrate; and a surface of the first substrate which is arranged to face the surface of the first substrate. An electric field applying mechanism having electrodes on opposite surfaces, a voltage is applied between the wiring of the envelope and the electrode of the electric field applying mechanism, and the fibrous carbon and the electric field applying mechanism are provided. An apparatus for manufacturing an image forming apparatus, characterized in that an electric discharge is generated between the electrode and an electrode of the image forming apparatus. 5. When a voltage is applied between the wiring of the envelope and the electrode of the electric field applying mechanism, the distance between the surface of the first substrate and the electrode of the electric field applying mechanism is The apparatus for manufacturing an image forming apparatus according to claim 4, wherein the distance is set to be narrower than the distance between the cathode electrode and the anode electrode in the image forming apparatus. 6. The apparatus for manufacturing an image forming apparatus according to claim 4, wherein the electric field applying mechanism has planar conductors arranged in parallel with the surface of the first substrate as electrodes. 7. The planar conductor has a substantially rectangular shape, and the longitudinal direction thereof is different from the longitudinal direction of the wiring to which the cathode electrode of the electron-emitting device which is formed on the opposing first substrate is connected. The apparatus for manufacturing an image forming apparatus according to claim 6, wherein 8. The apparatus for manufacturing an image forming apparatus according to claim 4, wherein the electric field applying mechanism has a conductor wire arranged in parallel with the surface of the first substrate as an electrode. 9. The electric field applying mechanism comprises a thin plate having a linear tip and having the linear tip arranged on a plane parallel to the surface of the first substrate as an electrode. Or the manufacturing apparatus of the image forming apparatus described in 5. 10. The electric field applying mechanism is capable of moving an electrode of the electrolysis applying mechanism in parallel with the surface of the first substrate while keeping a constant distance therebetween. 2. An image forming apparatus manufacturing apparatus according to item 1. 11. An apparatus for manufacturing an image forming apparatus according to claim 4, wherein a part of an electron emitting portion of the fibrous carbon formed on a surface of the cathode electrode is eliminated. A method of manufacturing an image forming apparatus, comprising the step of causing a new electron emission portion to appear. 12. The step of causing a part of the electron emitting portion of the fibrous carbon formed on the surface of the cathode electrode to disappear and exposing a new electron emitting portion, the wiring provided in the envelope and the 12. A voltage is applied between the electrode of the electric field applying mechanism and an electron emission current from the electron emission device, and the process is terminated when the electron emission current reaches a predetermined value. A method for manufacturing an image forming apparatus according to item 1. 13. The image forming apparatus according to claim 11, wherein the voltage applied between the wiring provided in the envelope and the electrode of the electric field applying mechanism is applied in a pulsed manner. Manufacturing method.