JP3302293B2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention uses an antistatic film
More particularly, the present invention relates to an image forming apparatus having a spacer provided with an antistatic film.

[0002]

2. Description of the Related Art Conventionally, two types of electron emitting devices, a hot cathode device and a cold cathode device, are known. Among these, among the cold cathode devices, for example, a surface conduction type emission device, a field emission type device (hereinafter referred to as FE type), a metal / insulating layer / metal type emission device (hereinafter referred to as MIM type), and the like are known. I have.

[0003] As a surface conduction type emission element, for example,
M. I. Elinson, Radio Eng. Ele
ctron Phys. , 10, 1290, (196
5) and other examples described later are known.

The surface conduction electron-emitting device utilizes a phenomenon in which an electron is emitted when a current flows in a small-area thin film formed on a substrate in parallel with the film surface. As this surface conduction type emission element, Sn described by Elinson et al.
In addition to those using the O ₂ thin film, those using the Au thin film [G. Dittmer: “Thin Solid Fi
lms ", 9,317 (1972)] and In ₂ O ₃ /
According to SnO ₂ thin film [M. Hartwell an
d C.I. G. FIG. Fonstad: "IEEE Tran
s. ED Conf. “, 519 (1975)] and those using carbon thin films [Hisashi Araki et al .: Vacuum, Vol. 26,
No. 1, 22 (1983)].

[0005] As a typical example of the element structure of these surface conduction electron-emitting devices, FIG. Hartwel
1 shows a plan view of an element according to the present invention. In FIG.
Reference numeral 1 denotes a substrate, and reference numeral 3004 denotes a conductive thin film made of a metal oxide formed by sputtering. The conductive thin film 3004 is formed in an H-shaped planar shape as shown. An electron emission portion 3005 is formed by performing an energization process called energization forming described later on the conductive thin film 3004. The interval L in the figure is 0.5 to 1 [mm], and W is
It is set at 0.1 [mm]. In addition, for convenience of illustration, the electron emitting portion 3005 is shown in a rectangular shape at the center of the conductive thin film 3004, but this is a schematic one, and the position and shape of the actual electron emitting portion are faithfully represented. Not necessarily.

[0006] M. In the above-described surface conduction electron-emitting device including the device by Hartwell et al., The electron-emitting portion 3005 is formed by subjecting the conductive thin film 3004 to an energization process called energization forming before electron emission.
It was common to form That is, the energization forming means energizing by applying a constant DC voltage to both ends of the conductive thin film 3004, or a DC voltage which is boosted at a very slow rate of, for example, about 1 V / min.
The electron emitting portion 30 in a state where the conductive thin film 3004 is locally destroyed, deformed or deteriorated, and is in an electrically high resistance state.
05 is formed. Note that a part of the conductive thin film 3004 that has been locally broken, deformed, or altered includes
Cracks occur. When an appropriate voltage is applied to the conductive thin film 3004 after the energization forming, electron emission is performed in the vicinity of the crack.

[0007] Examples of the FE type are described in, for example, W.S. P.
Dyke & W. W. Dolan, "Field emi
session ", Advance in Electro
nPhysics, 8, 89 (1956) or C.I. A. Spindt, "Physical pr
operations of thin-film figure
-Ld emission cathodes wit
h molybdenium cones ", J. Ap
pl. Phys. , 47, 5248 (1976).

As a typical example of the FE type device configuration, FIG. A. 1 shows a cross-sectional view of a device by Spindt et al. In the figure, reference numeral 3010 denotes a substrate;
Is an emitter wiring made of a conductive material, 3012 is an emitter cone, 3013 is an insulating layer, and 3014 is a gate electrode. This device comprises an emitter cone 3012 and a gate electrode 3
By applying an appropriate voltage during 014, field emission is caused from the tip of the emitter cone 3012.

As another element configuration of the FE type, FIG.
There is also an example in which the emitter and the gate electrode are arranged on the substrate almost in parallel with the substrate plane, instead of the laminated structure as shown in FIG.

As an example of the MIM type, for example,
C. A. Mead, “Operation of tu
nnel-emission Devices, J. et al. A
ppl. Phys. , 32, 646 (1961). FIG. 2 shows a typical example of an MIM type device configuration.
0 is shown. This figure is a cross-sectional view.
Is a substrate, 3021 is a lower electrode made of metal, 3022 is a thin insulating layer having a thickness of about 100 Å, 302
Reference numeral 3 denotes an upper electrode made of a metal having a thickness of about 80 to 300 angstroms. In the MIM type, the upper electrode 302
By applying an appropriate voltage between the third electrode 301 and the lower electrode 3021, electrons are emitted from the surface of the upper electrode 3023.

The above-mentioned cold cathode device can obtain electrons at a lower temperature than the hot cathode device, and therefore does not require a heater for heating. Therefore, the structure is simpler than that of the hot cathode element, and a fine element can be produced. Also,
Even if a large number of elements are arranged on a substrate at a high density, problems such as thermal melting of the substrate hardly occur. In addition, unlike the hot cathode device, which operates by heating the heater, the response speed is slow, and the cold cathode device also has the advantage that the response speed is fast.

For this reason, research for applying the cold cathode device has been actively conducted.

For example, the surface conduction electron-emitting device has the advantage of being able to form a large number of devices over a large area because it has a particularly simple structure and is easy to manufacture among the cold cathode devices. Therefore, for example, Japanese Patent Application Laid-Open No.
As disclosed in JP-A-332-332, a method for arranging and driving a large number of elements has been studied. Also,
As for the application of the surface conduction electron-emitting device, for example, an image forming apparatus such as an image display device and an image recording device, and a charged beam source have been studied.

Particularly, as an application to an image display device, for example, as disclosed in US Pat. No. 5,066,883, JP-A-2-257551 and JP-A-4-28137 by the present applicant, An image display device using a combination of a conduction emission device and a phosphor that emits light when irradiated with an electron beam has been studied. An image display device using a combination of a surface conduction electron-emitting device and a phosphor is expected to have better characteristics than other conventional image display devices. For example, it can be said that it is superior in that it does not require a backlight because it is a self-luminous type and that it has a wide viewing angle, as compared with a liquid crystal display device that has become popular recently.

A method of driving a large number of FE types is disclosed in US Pat. No. 4,904,895 according to the present application.
Is disclosed. Further, as an example in which the FE type is applied to an image display device, for example, R.F. The flat panel display reported by Meyer et al. Is known. [R. Meye
r: “Recent Development onM
micro-tips Display at LET
I ", Tech. Digest of 4th In
t. Vacuum Microele-ctronic
s Conf. , Nagahama, pp .; 6-9 (1
991)] An example in which a number of MIM types are arranged and applied to an image display device is disclosed in, for example, Japanese Patent Application Laid-Open No.
No. 5738.

Among the image forming apparatuses using the above-described electron-emitting devices, a flat display device having a small depth has been attracting attention as a replacement for a cathode-ray tube display device because of its space saving and light weight. .

FIG. 21 is a perspective view showing an example of a display panel portion forming a flat type image display device, and a part of the panel is cut away to show the internal structure.

In the figure, reference numeral 3115 denotes a rear plate, 3116
Denotes a side wall, 3117 denotes a face plate, and a rear plate 3115, a side wall 3116, and a face plate 3
117 forms an envelope (airtight container) for maintaining the inside of the display panel in a vacuum.

A substrate 3111 is fixed to the rear plate 3115. On this substrate 3111, N × M cold cathode elements 3112 are formed (N and M are positive integers of 2 or more. It is set appropriately according to the target number of display pixels.) Further, the N × M cold cathode elements 31
Reference numeral 12 denotes M row-direction wirings 311 as shown in FIG.
Three and N column-directional wirings 3114 are provided.
The part constituted by the substrate 3111, the cold cathode element 3112, the row direction wiring 3113 and the column direction wiring 3114 is called a multi electron beam source. In addition, the row direction wiring 3
An insulating layer (not shown) is formed at least at a portion where the column 113 and the column direction wiring 3114 intersect with each other.
Electrical insulation is maintained.

A phosphor film 3118 made of a phosphor is formed on the lower surface of the face plate 3117, and phosphors of three primary colors of red (R), green (G), and blue (B) (not shown) are applied. Divided. A black body (not shown) is provided between the phosphors of the respective colors constituting the fluorescent film 3118, and a metal back 3119 made of Al or the like is formed on the surface of the fluorescent film 3118 on the rear plate 3115 side. ing.

Dx1 to Dxm and Dy1 to Dyn and Hv are electric connection terminals of an airtight structure provided for electrically connecting the display panel to an electric circuit (not shown). Dx1 to Dxm are electrically connected to the row direction wiring 3113 of the multi-electron beam source, Dy1 to Dyn are electrically connected to the column direction wiring 3114 of the multi-electron beam source, and Hv is electrically connected to the metal back 3119.

The inside of the airtight container is 10 ^-6 Torr.
r, and as the display area of the image display device increases, means for preventing deformation or destruction of the rear plate 3115 and the face plate 3117 due to a pressure difference between the inside and the outside of the airtight container is required. . Rear plate 3115 and face plate 31
The method of increasing the thickness of 16 increases not only the weight of the image display device but also distortion and parallax of the image when viewed from an oblique direction. On the other hand, in FIG. 21, a structural support (called a spacer or a rib) 312 made of a relatively thin glass plate and supporting the atmospheric pressure is used.
0 is provided. In this way, the distance between the substrate 3111 on which the multi-beam electron source is formed and the face plate 3116 on which the fluorescent film 3118 is formed is usually kept at a sub-millimeter to several millimeters, and the inside of the airtight container is kept at a high vacuum as described above. ing.

In the image display apparatus using the above-described display panel, when a voltage is applied to each cold cathode element 3112 through the external terminals Dx1 to Dxm and Dy1 to Dyn, electrons are emitted from each cold cathode element 3112. At the same time, a high voltage of several hundred [V] to several [kV] is applied to the metal back 3119 through the external terminal Hv to accelerate the emitted electrons and collide with the inner surface of the face plate 3117. As a result, the phosphors of each color forming the fluorescent film 3118 are excited and emit light, and an image is displayed.

[0024]

The display panel of the image display device described above has the following problems.

First, spacer charging may be caused by a part of electrons emitted from an electron source near the spacer 3120 hitting the spacer 3120 or by ionization of ions by the action of the emitted electrons to adhere to the spacer. There is. The electrons emitted from the cold cathode element 3112 due to the charging of the spacer are bent in their trajectories, reach a position different from the normal position on the phosphor, and the image near the spacer is distorted and displayed.

Second, in order to accelerate the electrons emitted from the cold cathode device 3112, a high voltage of several hundred V or more (ie, 1 k) is applied between the multi-beam electron source and the face plate 3117.
V / mm or more), the spacer 3
There is a concern about creeping discharge on the surface of the H.120. In particular, when the spacer is charged as described above, discharge may be induced.

In order to solve this problem, it has been proposed to remove a charge by making a minute current flow through the spacer. There, a high-resistance thin film is formed on the surface of an insulating spacer so that a minute current flows on the surface of the spacer. The antistatic film used here is tin oxide or a mixed crystal thin film of tin oxide and indium oxide or a metal film. The semiconductor type thin film such as tin oxide used in the above proposal has a high oxygen content such as being applied to a gas sensor. Since it is sensitive to gas, its resistance value easily changes in an atmosphere. In addition, since these materials or metal films have low specific resistance, it is necessary to form them in an island shape or to make them extremely thin in order to increase the resistance. In other words, conventional high resistance films have difficulty in reproducibility of film formation,
There is a drawback that the resistance value is apt to change in a heating process such as frit sealing or baking in a display manufacturing process.

The object of the present invention is to overcome the above-mentioned drawbacks of the conventional spacer, and to provide an electron beam generator having an electrode and an electron source using an electron-emitting device. It is an object of the present invention to propose an electron beam generator in which the trajectory of emitted electrons does not change even if a spacer is arranged in the electron beam.

Another object of the present invention is to provide an image forming apparatus in which, for example, a surface conduction electron-emitting device is used as an electron-emitting device and an image is formed by electrons emitted from the electron source, there is no displacement of a light-emitting position and the like. It is an object of the present invention to provide a new image forming apparatus having a long life and high reliability.

[0030]

The present invention has the following means to solve the above-mentioned problems. (1) An image is formed by an electron source and electrons generated from the electron source.
An image forming apparatus having an image forming member for forming an image.
And a support member for supporting an image forming space inside the apparatus.
A high-resistance thin film is formed on the surface, and an island is formed on the high-resistance thin film.
Antistatic film having conductive fine particles
An image forming apparatus comprising:

(2) An image forming apparatus comprising the island-like conductive particles in and on the high-resistance thin film.

(3) The image forming apparatus as described above, wherein the conductive particles are the thin films formed in an island shape.

(4) The high-resistance thin film is 0.1 to 10
Image type characterized by having a specific resistance of ⁸ [Ωcm]
Equipment .

(5) The high-resistance thin film is made of Cr, Ni,
An image forming apparatus comprising any one of oxides of Cu and a nitride of an alloy of a transition metal and Al.

(6) The conductive particles formed in an island shape are made of Be, Mg, Al, Ti, Ni, Cs, Ba, P
t, Au, Ag, Rh, Ir, Sb, Sn, Pb, G
a, Zn, In, Cd, Cu, Co, Rh, Fe, M
Metals of n, Cr, V, Zr, Nb, Mo, W and alloys composed of a plurality of the above metals, SnO ₂ oxide, MoS ₂ , W
An image form characterized by being one of the sulfides of S ₂
Equipment .

(7) The support member is a spacer.
An image forming apparatus comprising:

(8) The support member is provided with the image forming space.
An image forming apparatus, characterized in that it is a side wall between them .

(9) The electron source is a surface conduction type electron emission device.
An image forming apparatus comprising an output element .

[0039]

[0040]

[Operation] According to the present invention, a high-resistance film is formed on the surface of the insulating member.
Further, by dispersing the conductive fine particles discretely in an island shape, a sufficient antistatic effect can be obtained, and an image forming apparatus having an antistatic film with high stability can be obtained.

Further, by applying this antistatic film to the surface of the spacer which supports the internal space of the image display device, the disturbance of the beam near the spacer is suppressed, and the position where the beam collides with the phosphor and the original light emission is performed. It is possible to prevent the occurrence of a positional shift from the fluorescent material to be prevented, prevent loss of luminance, and manufacture a display device capable of displaying a clear image.

That is, the image forming apparatus of the present invention forms
The antistatic film has a small change in resistance even after heat treatment, so the environment in which it is used is a vacuum like an electron beam display,
This is particularly effective for applications that include high-temperature heat treatment and vacuum heat treatment in the manufacturing process.

The antistatic film formed on the image forming apparatus of the present invention is effective for preventing the spacers of the image display device from being charged. However, the present invention is not limited to this. It can also be used as a membrane.

Also, the present invention provides an electron source having a plurality of cold cathode devices, an electrode for controlling electrons emitted from the electron source, a target for irradiating the electrons emitted from the electron source, In an electron beam apparatus having a spacer disposed between a source and the electrode, the spacer has a high-resistance film on a surface, and has a conductive film on a contact surface between the electron source and the electrode. The high-resistance film is electrically connected to the electron source and the electrode via the conductive film, and conductive particles are discretely formed in islands on the surface of the high-resistance film. An electron beam generator characterized in that the electron beam generator is applied to an electron beam.

The electron beam apparatus of the present invention may have the following form.

The electron beam device is an accelerating electrode in which the electrode accelerates electrons emitted from the electron source. The electron beam device irradiates the target with electrons emitted from the cold cathode device in accordance with an input signal, thereby forming an image. Forming an image forming apparatus. In particular, an image display device in which the target is a phosphor is provided.

The cold cathode device is a cold cathode device having a conductive film including an electron emitting portion between a pair of electrodes, and is particularly preferably a surface conduction type emission device.

The electron source is an electron source having a simple matrix arrangement having a plurality of cold cathode elements arranged in a matrix with a plurality of row-direction wirings and a plurality of column-direction wirings.

In the electron source, a plurality of rows of cold cathode devices each having a plurality of cold cathode devices arranged in parallel and connected at both ends are arranged (referred to as a row direction), and a direction perpendicular to the wiring (column direction). A control electrode (also referred to as a grid) disposed above the cold cathode device along with the cold cathode device forms a ladder-shaped electron source for controlling electrons from the cold cathode device.

According to the concept of the present invention, the present invention is not limited to an image forming apparatus suitable for display, but may be used as an alternative light source such as a light emitting diode of an optical printer including a photosensitive drum and a light emitting diode. Alternatively, the above-described image forming apparatus can be used. In this case, by appropriately selecting the above-mentioned m row-directional wirings and n column-directional wirings, the present invention can be applied not only to a linear light emitting source but also to a two-dimensional light emitting source. In this case, the image forming member is not limited to a substance that emits light directly, such as a phosphor used in the following embodiments, and a member that forms a latent image by electron charging can also be used.

Further, according to the concept of the present invention, the present invention is applicable to a case where a member to be irradiated with electrons emitted from an electron source is other than an image forming member such as a phosphor as in an electron microscope. Is applicable. Therefore, the present invention can also take a form as a general electron beam apparatus that does not specify a member to be irradiated.

[0053]

BEST MODE FOR CARRYING OUT THE INVENTION

(1) Characteristic part of the invention The spacer that supports the space in which the electron source and the image forming member are stored has an insulating property enough to withstand the high voltage applied between the electron source and the metal back, and the surface is charged. It is necessary to have surface conductivity enough to prevent it.

FIG. 1 is a schematic cross-sectional view of an antistatic film according to the present invention. Reference numeral 1 denotes an insulating member to be subjected to antistatic, and reference numeral 2 denotes an antistatic film formed on the surface of the insulating member 1. The antistatic film 2 is composed of a high resistance thin film 3 and discrete island-shaped particles 4 formed on the surface thereof.

FIG. 2 shows another structure of the antistatic film of the present invention. The antistatic film 2 is composed of a high-resistance thin film 3 and discretely formed particles 4 in FIG. However, the particles 4 are embedded in the high-resistance thin film 3 and partially exposed on the surface.

Hereinafter, the antistatic film of the present invention will be described in detail.

[Material of Spacer] Examples of the insulating substrate of the spacer include quartz glass, glass having a reduced impurity content such as Na, soda lime glass, and ceramic members such as alumina. Preferably, the insulating substrate has a coefficient of thermal expansion close to those of the envelope and the member forming the insulating substrate of the electron source.

[Resistance Value of Spacer] The resistance value Rs of the spacer of the present invention is set in a desirable range from the viewpoint of antistatic and power consumption. Sheet resistance Rs from the viewpoint of antistatic
Is preferably 10 ¹² Ω or less. In order to obtain a sufficient antistatic effect, the resistance is more preferably 10 ¹¹ Ω or less. Although the lower limit of the sheet resistance depends on the spacer shape and the voltage applied between the spacers, it is usually preferably 10 ⁵ Ω or more.

[Thickness of Antistatic Film] The thickness t of the antistatic film formed on the insulating material is preferably in the range of 10 nm to 1 μm. Although it depends on the surface energy of the material, the adhesion to the substrate, and the substrate temperature, a thin film of 10 nm or less is generally formed in the shape of an island, and has an unstable resistance and poor reproducibility. On the other hand, when the film thickness is 1 μm or more, the film stress increases, the risk of film peeling increases, and the film formation time increases, resulting in poor productivity. Therefore, the film thickness is desirably 50 to 500 nm.

[Specific Resistance of Antistatic Film] The sheet resistance Rs is ρ / t, and from the preferable range of Rs and t described above, the specific resistance ρ of the antistatic film is 0.1 to 10 ⁸ Ωcm. There is a need. Further, in order to realize a more preferable range of the sheet resistance and the film thickness, the thickness is preferably set to 10 ² to 10 ⁶ Ωcm.

[Temperature coefficient of resistance of antistatic film] As described above, the temperature of the spacer rises when a current flows through the antistatic film formed thereon or when the entire display generates heat during operation. If the temperature coefficient of resistance of the antistatic film is a large negative value, the resistance value decreases when the temperature increases, the current flowing through the spacer increases, and the temperature further increases. And the current continues to increase until the power supply limit is exceeded. The value of the temperature coefficient of resistance at which such a runaway of current occurs is empirically a negative value of 1% or more. That is, the resistance temperature coefficient of the antistatic film is desirably less than -1%.

[Material of High Resistance Thin Film] Examples of the high resistance antistatic film satisfying the above conditions include oxide thin films such as chromium, nickel and copper, and transition metal and aluminum alloy nitrogen compound thin films. .

[Material of island-shaped conductive particles] The particles formed into discrete islands on the surface of the antistatic film have high conductivity in each particle and secondary electron emission efficiency more than the antistatic film. It is desirable to use a substance having a small value. These are because it is difficult to charge even when the electrons emitted from the electron-emitting device hit the spacer. Such substances include Be, M
g, Al, Ti, Ni, Cs, Ba, Pt, Au, A
g, Rh, Ir, Sb, Sn, Pb, Ga, Zn, I
n, Cd, Cu, Co, Rh, Fe, Mn, Cr, V,
Examples include metals such as Zr, Nb, Mo, and W and alloys composed of a plurality of metals, oxides such as SnO _2, and sulfides such as MoS ₂ and WS ₂ .

[Method of Forming Insulated Conductive Particles] Particles applied and formed discretely on the surface of the high resistance antistatic film and the surface of the high resistance antistatic film are formed by sputtering, reactive sputtering, electron beam It can be formed on an insulating member by thin film forming means such as vapor deposition, ion plating, ion assist vapor deposition, and CDV.

(2) Outline of Image Display Device Next, the configuration and manufacturing method of a display panel of an image display device to which the present invention is applied will be described with reference to specific examples.

FIG. 3 is a perspective view of a display panel used in the embodiment, in which a part of the panel is cut away to show the internal structure.

In the figure, 1015 is a rear plate, 1016
Is a side wall, 1017 is a face plate, and 1015
An airtight container for maintaining the inside of the display panel at a vacuum is formed by 1017 to 1017. When assembling an airtight container, it is necessary to seal the joints of each member to maintain sufficient strength and airtightness.For example, apply frit glass to the joints, and in air or nitrogen atmosphere, Sealing was achieved by baking at 400 to 500 degrees for 10 minutes or more. A method of evacuating the inside of the airtight container to a vacuum will be described later. The inside of the airtight container is 1
Since a vacuum of about 0 ^-6 [Torr] is maintained, a spacer 1020 is provided as an anti-atmospheric structure for the purpose of preventing the hermetic container from being destroyed by atmospheric pressure or unexpected impact.

The rear plate 1015 has a substrate 1011
Is fixed, but the cold cathode element 1012 is provided on the substrate.
Are formed N × M. (N and M are positive integers of 2 or more and are appropriately set according to the target number of display pixels. For example, in a display device for displaying high-definition television, N = 3000 and M It is desirable to set the number to be equal to or greater than 1000.) The N × M cold cathode elements are arranged in a simple matrix by M row-directional wirings 1013 and N column-directional wirings 1014. The portion constituted by the components 1011 to 1014 is called a multi-electron beam source.

The material, shape, and manufacturing method of the cold cathode device are not limited as long as the multi-electron beam source used in the image display device of the present invention is an electron source in which cold cathode devices are arranged in a simple matrix. Therefore, for example, a cold cathode device such as a surface conduction type emission device, an FE type, or an MIM type can be used.

Next, the structure of a multi-electron beam source in which a surface conduction electron-emitting device (described later) as a cold cathode device is arranged on a substrate and wired in a simple matrix will be described.

FIG. 4 is a plan view of the multi-electron beam source used for the display panel of FIG. Surface conduction type emission devices similar to those shown in FIG. 9 described later are arranged on the substrate 1011, and these devices are wired in a simple matrix by row-direction wirings 1013 and column-direction wirings 1014. An insulating layer (not shown) is formed between the electrodes at the intersections of the row direction wirings 1013 and the column direction wirings 1014 to maintain electrical insulation.

FIG. 5 shows a cross section along the line BB 'in FIG.

Incidentally, the multi-electron source having such a structure is as follows.
Row direction wiring 1013, column direction wiring 1
014, an inter-electrode insulating layer (not shown), a device electrode of a surface conduction electron-emitting device, and a conductive thin film are formed, and then power is supplied to each device via a row wiring 1013 and a column wiring 1014 to form an energization. (Described later) and an activation process (described later).

In the present embodiment, the substrate 1011 of the multi-electron beam source is fixed to the rear plate 1015 of the airtight container.
When the substrate 1 has a sufficient strength, the substrate 101 of the multi-electron beam source is used as a rear plate of the hermetic container.
1 itself may be used.

On the lower surface of the face plate 1017, a fluorescent film 1018 is formed. Since the present embodiment is a color display device, a CR film
Phosphors of three primary colors of red, green and blue used in the field of T are separately applied. The phosphors of each color are separately applied in stripes as shown in FIG. 6A, for example, and black conductors 1010 are provided between the stripes of the phosphors. The purpose of providing the black conductor 1010 is to prevent the display color from shifting even if the electron beam irradiation position is slightly shifted, and to prevent the reflection of external light to prevent the display contrast from lowering. And preventing charge-up of the fluorescent film by the electron beam. Black conductor 1
For 010, graphite was used as a main component, but other materials may be used as long as they are suitable for the above purpose.

The method of applying the phosphors of the three primary colors is not limited to the stripe arrangement shown in FIG. 6A, but may be, for example, a delta arrangement as shown in FIG. Other arrangements may be used.

When a monochrome display panel is manufactured, the phosphor film 1018 may be formed of a single-color phosphor material, and the black conductive material may not necessarily be used.

Further, a metal back 1019 known in the field of CRT is provided on the surface of the fluorescent film 1018 on the rear plate side.
Is provided. The purpose of providing the metal back 1019 is
A part of the light emitted from the fluorescent film 1018 is specularly reflected to improve the light utilization rate, and the fluorescent film 101
8 to protect it, to act as an electrode for applying an electron beam acceleration voltage, and to act as a conductive path for excited electrons of the fluorescent film 1018. The metal back 1019 was formed by forming the fluorescent film 1018 on the face plate substrate 1017, smoothing the surface of the fluorescent film, and vacuum-depositing Al thereon.
Note that when a fluorescent material for low voltage is used for the fluorescent film 1018, the metal back 1019 is not used.

Although not used in the present embodiment, for the purpose of applying an acceleration voltage and improving the conductivity of the fluorescent film, a gap between the face plate substrate 1017 and the fluorescent film 1018 is formed.
For example, a transparent electrode made of ITO may be provided.

FIG. 7 is a schematic sectional view taken along the line AA 'of FIG. 3, and the numbers of the respective parts correspond to those of FIG. Spacer 102
Numeral 0 indicates that a high-resistance film 1020b is formed on the surface of the insulating member 1020a for the purpose of preventing electrification, and the inside of the face plate 1017 (eg, the metal back 1019) and the substrate 1
011 (row direction wiring 1013 or column direction wiring 1
014) on the contact surface of the spacer facing the low resistance film 1020
It is made of a member on which a film c is formed, and is arranged by a necessary number and at a necessary interval to achieve the above-mentioned object, and is fixed to the inside of the face plate and the surface of the substrate 1011 by the bonding material 1041. Also, the high resistance film 1020
b is formed on at least the surface of the insulating member 1020a that is exposed to the vacuum in the hermetic container, and the face plate is formed via the low-resistance film 1020c on the spacer 1020 and the bonding material 1041. It is electrically connected to the inside of 1017 (metal back 1019 etc.) and the surface of substrate 1011 (row direction wiring 1013 or column direction wiring 1014). In the embodiment described here,
The shape of the spacer 1020 is a thin plate.
13 and is electrically connected to the row wiring 1013.

As the spacer 1020, the substrate 1011
Has insulating properties enough to withstand high voltage applied between the upper row direction wiring 1013 and column direction wiring 1014 and the metal back 1019 on the inner surface of the face plate 1017;
In addition, it is necessary to have conductivity enough to prevent the surface of the spacer 1020 from being charged. This is as described above.

The insulating member 1020a of the spacer 1020
Examples thereof include quartz glass, glass with a reduced impurity content such as Na, soda lime glass, and ceramic members such as alumina. The insulating member 10
Preferably, 20a has a coefficient of thermal expansion close to that of the member forming the airtight container and the substrate 1011.

As described above, the high resistance film 1020b has a surface resistance of 10 ⁵ [Ω] in consideration of maintaining the antistatic effect and suppressing power consumption due to leakage current.
/ □] to 10 ¹² [Ω / □], and the above-mentioned various materials are used as the material.

Further, the low resistance film 1020c is the same as the high resistance film 1
It suffices to select a resistance value sufficiently lower than that of 020b.
i, Cr, Au, Mo, W, Pt, Ti, Al, Cu,
Pd and other metals or alloys, and Pd, Ag, Au,
A printed conductor composed of a metal such as RuO ₂ or Pd-Ag or a metal oxide and glass, or In ₂ O ₃ —SnO
It is appropriately selected from transparent conductors such as ₂ and semiconductor materials such as polysilicon.

The bonding material 1041 needs to have conductivity so that the spacer 1020 is electrically connected to the row wiring 1013 and the metal back 1019. That is, frit glass to which a conductive adhesive, metal particles, or a conductive filler is added is preferable.

Dx1 to Dxm and Dy1 to Dy
n and Hv are air-tightly structured electrical connection terminals provided for electrically connecting the display panel to an electric circuit (not shown). Dx1 to Dxm are electrically connected to the row wiring 1013 of the multi-electron beam source, Dy1 to Dyn are electrically connected to the column wiring 1014 of the multi-electron beam source, and Hv is electrically connected to the metal back 1019 of the face plate.

In order to evacuate the inside of the airtight container, after assembling the airtight container, an exhaust pipe (not shown) and a vacuum pump are connected, and the inside of the airtight container is evacuated to a degree of vacuum of about 10 ^-7 [Torr]. Exhaust until After that, the exhaust pipe is sealed,
In order to maintain the degree of vacuum in the airtight container, a getter film (not shown) is formed at a predetermined position in the airtight container immediately before or after sealing. The getter film is, for example, a film formed by heating and depositing a getter material containing Ba as a main component by a heater or high-frequency heating, and the inside of the hermetic container is 1 × 10 ⁻⁵ or 1 × by the adsorption action of the getter film.
The degree of vacuum is maintained at 10 ^-7 [Torr].

In the image display apparatus using the display panel described above, when a voltage is applied to each of the cold cathode devices 1012 through the external terminals Dx1 to Dxm and Dy1 to Dyn, electrons are emitted from each of the cold cathode devices 1012. At the same time, a high voltage of several hundred [V] to several [kV] is applied to the metal back 1019 through the external terminal Hv to accelerate the emitted electrons and collide with the inner surface of the face plate 1017. As a result, the phosphor of each color forming the fluorescent film 1018 is excited and emits light, and an image is displayed.

Normally, the voltage applied to 1012 to the surface conduction electron-emitting device of the present invention, which is a cold cathode device, is 12 to 16
[V], metal back 1019 and cold cathode element 101
The distance d between the metal back 1019 and the cold cathode element 1012 is about 0.1 [mm] to 8 [mm].
It is about 1 [kV] to about 10 [kV].

The basic configuration and manufacturing method of the display panel according to the embodiment of the present invention, and the outline of the image display device have been described above.

(3) Method of Manufacturing Multi-Electron Beam Source Next, a method of manufacturing the multi-electron beam source used in the display panel of the above embodiment will be described. The material, shape, and manufacturing method of the cold cathode device are not limited as long as the multi-electron beam source used for the image display device of the present invention is an electron source in which cold cathode devices are arranged in a simple matrix. Therefore, for example, a cold cathode device such as a surface conduction type emission device, an FE type, or an MIM type can be used.

However, under the circumstances where a display device having a large surface screen and an inexpensive display device is required, among these cold cathode devices, a surface conduction type emission device is particularly preferable. That is, in the FE type, since the relative position and shape of the emitter cone and the gate electrode greatly affect the electron emission characteristics, extremely high-precision manufacturing technology is required, but this achieves a large area and a reduction in manufacturing cost. Is a disadvantageous factor. In the case of the MIM type, it is necessary to make the thicknesses of the insulating layer and the upper electrode thin and uniform, which is also a disadvantageous factor in achieving a large area and a reduction in manufacturing cost. On the other hand, since the surface conduction electron-emitting device has a relatively simple manufacturing method, it is easy to increase the area and reduce the manufacturing cost. In addition, the inventors have found that among the surface conduction electron-emitting devices, those in which the electron-emitting portion or its peripheral portion is formed of a fine particle film have particularly excellent electron-emitting characteristics and can be easily manufactured. Therefore, it can be said that it is most suitable for use in a multi-electron beam source of a high-luminance, large-screen image display device. Therefore, in the display panel of the above embodiment, a surface conduction electron-emitting device having the electron-emitting portion or its peripheral portion formed of a fine particle film was used. Therefore, the basic structure, manufacturing method and characteristics of a suitable surface conduction electron-emitting device will be described first, and then the structure of a multi-electron beam source in which a large number of devices are arranged in a simple matrix will be described.

(Suitable Device Configuration and Manufacturing Method of Surface Conduction Emission Device) A typical configuration of a surface conduction electron-emitting device in which an electron-emitting portion or its peripheral portion is formed from a fine particle film is a flat type or a vertical type. Kinds are given.

(Planar surface conduction electron-emitting device) First, the structure and manufacturing method of a plane surface conduction electron-emitting device will be described. FIG. 9 shows a plan view (a) and a cross-sectional view (b) for explaining the configuration of a planar surface conduction electron-emitting device. In the figure, 1101 is a substrate, 1102 and 1
103, a device electrode; 1104, a conductive thin film; 1105, an electron-emitting portion formed by an energization forming process;
Reference numeral 13 denotes a thin film formed by the activation process.

As the substrate 1101, for example, various glass substrates such as quartz glass and blue plate glass, various ceramics substrates such as alumina, or an insulating layer made of, for example, SiO ₂ is formed on the various substrates described above. A stacked substrate or the like can be used.

The element electrodes 1102 and 1103 provided on the substrate 1101 in parallel with the substrate surface are formed of a conductive material. For example, N
i, Cr, Au, Mo, W, Pt, Ti, Cu, Pd,
Materials may be appropriately selected from metals such as Ag, alloys of these metals, metal oxides such as In ₂ O ₃ —SnO ₂ , and semiconductors such as polysilicon. To form an electrode, for example, a film forming technique such as vacuum evaporation and photolithography,
Although it can be easily formed by using a combination of patterning techniques such as etching, it may be formed by other methods (for example, printing technique).

The shapes of the device electrodes 1102 and 1103 are appropriately designed according to the application purpose of the electron-emitting device.
Generally, the electrode spacing L is usually designed by selecting an appropriate value from the range of several hundreds of angstroms to several hundreds of micrometers. It is in the range of ten micrometers. Further, regarding the thickness d of the device electrode,
Usually, an appropriate numerical value is selected from the range of several hundred angstroms to several micrometers.

A fine particle film is used for the conductive thin film 1104. The fine particle film mentioned here is a film containing many fine particles as a constituent element (including an island-shaped aggregate).
I mean If you examine the microparticle film microscopically, usually
A structure in which the individual fine particles are spaced apart, a structure in which the fine particles are adjacent to each other, or a structure in which the fine particles overlap each other is observed.

The particle size of the fine particles used in the fine particle film is in the range of several Angstroms to several thousand Angstroms, but preferably in the range of 10 Angstroms to 200 Angstroms. Further, the thickness of the fine particle film is appropriately set in consideration of various conditions described below. That is, the device electrode 11
02, or 1103, conditions necessary for satisfactorily performing energization forming described later, conditions necessary for setting the electric resistance of the fine particle film itself to an appropriate value described later. And so on. Specifically, it is set in the range of several Angstroms to several thousand Angstroms, but the range is preferably between 10 Angstroms and 500 Angstroms.

Materials that can be used to form the fine particle film include, for example, Pd, Pt, Ru, Ag,
Au, Ti, In, Cu, Cr, Fe, Zn, Sn, T
a, W, Pb and other metals, PdO, Sn
Oxides such as O ₂ , In ₂ O ₃ , PbO, Sb ₂ O ₃ , HfB ₂ , ZrB ₂ , LaB ₆ , CeB
Boride such as ₆ , YB ₄ , GdB ₄ ,
carbides such as iC, ZrC, HfC, TaC, SiC, WC, etc., nitrides such as TiN, ZrH, HfN, etc., semiconductors such as Si, Ge, carbon, etc. It is appropriately selected from these.

As described above, the conductive thin film 1104 is formed of a fine particle film.
It was set to be included from 10 ³ to a range of 10 ⁷ [Ω / □].

The conductive thin film 1104 and the device electrode 11
Since it is desirable that the wires 02 and 1103 be electrically connected well, they have a structure in which a part of each overlaps with the other. In the example of FIG. 9, the overlapping manner is such that the substrate, the device electrode, and the conductive thin film are stacked in this order from the bottom, but in some cases, the substrate, the conductive thin film, and the device electrode are stacked in this order from the bottom. I can't tell.

The electron emitting portion 1105 is a crack-like portion formed in a part of the conductive thin film 1104, and has an electrically higher resistance than the surrounding conductive thin film. The crack is formed by performing a later-described energization forming process on the conductive thin film 1104. Fine particles having a particle size of several Angstroms to several hundred Angstroms may be arranged in the crack. Since it is difficult to accurately and accurately show the actual position and shape of the electron-emitting portion, they are schematically shown in FIG.

The thin film 1113 is a thin film made of carbon or a carbon compound, and covers the electron emitting portion 1105 and its vicinity. The thin film 1113 is formed by performing an energization activation process described later after the energization forming process.

The thin film 1113 is made of any one of single crystal graphite, polycrystal graphite, and amorphous carbon, or a mixture thereof, and has a thickness of 500 Å or less, but preferably 300 Å or less. More preferred. Since it is difficult to accurately show the actual position and shape of the thin film 1113, it is schematically shown in FIG. In addition, in the plan view (a), an element in which a part of the thin film 1113 is removed is illustrated.

The basic structure of the preferred elements has been described above. In the examples, the following elements were used.

That is, blue glass was used for the substrate 1101, and Ni thin films were used for the device electrodes 1102 and 1103. The thickness d of the device electrode was 1000 [angstrom], and the electrode interval L was 2 [micrometer].

As a main material of the fine particle film, Pd or P
Using dO, the thickness of the fine particle film was about 100 [angstrom], and the width W was 100 [micrometer].

Next, a description will be given of a method of manufacturing a preferred flat surface conduction electron-emitting device.

FIGS. 10A to 10D are cross-sectional views for explaining the manufacturing process of the surface conduction electron-emitting device. The notation of each member is the same as in FIG.

1) First, as shown in FIG. 10A, device electrodes 1102 and 1103 are formed on a substrate 1101.

When forming, the substrate 1
After sufficiently washing 101 with a detergent, pure water and an organic solvent,
The material for the device electrode is deposited (as a deposition method,
For example, a vacuum film forming technique such as an evaporation method or a sputtering method may be used. ). Thereafter, the deposited electrode material is patterned by using a photolithography / etching technique, and a pair of device electrodes (1102 and 1102) shown in FIG.
Form 3).

2) Next, a conductive thin film 1104 is formed as shown in FIG.

In the formation, first, an organic metal solution is applied to the substrate (a), dried, heated and baked to form a fine particle film, and then patterned into a predetermined shape by photolithography and etching. . here,
The organic metal solution is a solution of an organic metal compound whose main element is a material of fine particles used for the conductive thin film (specifically, Pd was used as a main element in this example.
In the embodiment, the dipping method is used as the coating method, but other methods such as a spinner method and a spray method may be used. ).

As a method for forming a conductive thin film made of a fine particle film, a method other than the method of applying an organic metal container used in this embodiment, for example, a vacuum evaporation method, a sputtering method,
Alternatively, a chemical vapor deposition method or the like may be used.

3) Next, as shown in FIG. 11C, a forming power supply 1110 supplies the device electrodes 1102 and 1102 with each other.
3, an appropriate voltage is applied, and an energization forming process is performed to form the electron-emitting portion 1105.

[0117] The energization forming treatment is to energize the conductive thin film 1104 made of a fine particle film, to appropriately break, deform, or alter a part of the conductive thin film 1104 to change the structure to a structure suitable for emitting electrons. This is the process that causes A portion of the conductive thin film made of a fine particle film that has been changed to a structure suitable for emitting electrons (that is, the electron emitting portion 110
In 5), an appropriate crack is formed in the thin film.
Note that the electrical resistance measured between the device electrodes 1102 and 1103 is significantly increased after the formation of the electron emission portions 1105 as compared to before the formation.

FIG. 11 shows an example of an appropriate voltage waveform applied from the forming power supply 1110 in order to explain the energization method in more detail. When forming a conductive thin film made of a fine particle film, a pulsed voltage is preferable. In the case of this embodiment, a triangular wave pulse having a pulse width T1 is continuously generated at a pulse interval T2 as shown in FIG. Was applied. At that time, the peak value Vpf of the triangular wave pulse was sequentially increased. Also, monitor pulses Pm for monitoring the state of formation of the electron-emitting portion 1105 are inserted at appropriate intervals between the triangular-wave pulses, and the current flowing at that time is measured by the ammeter 1.
It was measured at 111.

In the embodiment, for example, in a vacuum atmosphere of about 10 −5 [Torr], for example, the pulse width T1 is 1 [millisecond] and the pulse interval T2 is 1
0 [millisecond], and the peak value Vpf is set to 0.
The pressure was increased by 1 [V]. Then, the monitor pulse Pm was inserted at a rate of one every time five triangular waves were applied. The monitor pulse voltage Vpm was set to 0.1 [V] so as not to adversely affect the forming process. Then, when the electric resistance between the device electrodes 1102 and 1103 becomes 1 × 10 6 [ohm], that is, the current measured by the ammeter 1111 at the time of application of the monitor pulse is 1 × 10 −7 [A When the following conditions were reached, the energization related to the forming process was terminated.

The above method is a preferable method for the surface conduction electron-emitting device of this embodiment. For example, the design of the surface conduction electron-emitting device such as the material and film thickness of the fine particle film or the element electrode interval L is changed. In such a case, it is desirable to appropriately change the energization conditions accordingly.

4) Next, as shown in FIG.
The device electrodes 1102 and 1103 are supplied from the activation power source 1112.
During the energization activation process, apply an appropriate voltage during
Improve electron emission characteristics.

The energization activation process is a process of energizing the electron emitting portion 1105 formed by the energization forming process under appropriate conditions and depositing carbon or a carbon compound in the vicinity thereof (in the figure). Shows a deposit made of carbon or a carbon compound as a member 1113.) Note that by performing the energization activation process, the emission current at the same applied voltage can be typically increased by 100 times or more as compared with before the energization activation process.

Specifically, 10 minus 4th power to 1
By applying a voltage pulse periodically in a vacuum atmosphere within the range of 0 to the fifth power [Torr], carbon or a carbon compound originating from an organic compound existing in the vacuum atmosphere is deposited. The deposit 1113 is any of single crystal graphite, polycrystalline graphite, and amorphous carbon, or a mixture thereof, and has a thickness of 500.
[Angstrom] or less, more preferably 300 [angstrom] or less.

In order to explain the energization method in more detail, FIG. 12A shows an example of an appropriate voltage waveform applied from the activation power supply 1112. In the present embodiment, the energization activation process is performed by applying a rectangular wave of a constant voltage periodically, but specifically, the voltage Vac of the rectangular wave is 14 [V],
The pulse width T3 is 1 [millisecond], and the pulse interval T4 is 10
[Milliseconds]. The above-mentioned energization conditions are preferable conditions for the surface conduction electron-emitting device of this embodiment, and when the design of the surface conduction electron-emitting device is changed, it is desirable to appropriately change the conditions accordingly.

Reference numeral 1114 shown in FIG. 9D denotes an anode electrode for capturing the emission current Ie emitted from the surface conduction electron-emitting device. The anode electrode 1114 is connected to a DC high-voltage power supply 1115 and an ammeter 1116. (Note that the substrate 1101
When the activation process is performed after the display panel is incorporated into the display panel, the phosphor screen of the display panel is connected to the anode electrode 1114.
Used as While the voltage is applied from the activation power supply 1112, the emission current Ie is measured by the ammeter 1116 to monitor the progress of the energization activation process.
12 is controlled. FIG. 12B shows an example of the emission current Ie measured by the ammeter 1116. When the pulse voltage is started to be applied from the activation power supply 1112, the emission current Ie increases with the passage of time, but eventually saturates. And hardly increase. As described above, when the emission current Ie is substantially saturated, the application of the voltage from the activation power supply 1112 is stopped, and the energization activation process ends.

The above-described energization conditions are preferable conditions for the surface conduction electron-emitting device of the present embodiment. If the conditions are changed in the design of the surface conduction electron-emitting device, the conditions should be changed accordingly. desirable.

As described above, the planar surface conduction electron-emitting device shown in FIG. 10E was manufactured.

(Vertical Surface Conduction Emission Device) Next, another typical structure of a surface conduction electron-emitting device in which the electron-emitting portion or its periphery is formed of a fine particle film, that is, a vertical surface-conduction emission device. The configuration of the element will be described.

FIG. 13 is a schematic cross-sectional view for explaining the basic structure of a vertical type. In FIG.
202 and 1203 are device electrodes, 1206 is a step forming member, 1204 is a conductive thin film using a fine particle film, 1205
Are electron-emitting portions formed by an energization forming process;
213 is a thin film formed by the activation process.

The difference between the vertical type and the flat type described above is that one of the element electrodes (1202) is provided on the step forming member 1206, and the conductive thin film 1204 is provided on the side surface of the step forming member 1206. It is in the point of coating. Therefore, the element electrode interval L in the planar type shown in FIG.
Is the step height L of the step forming member 1206 in the vertical type.
s. In addition, the substrate 1201, the element electrode 1
202 and 1203, conductive thin film 1 using fine particle film
For 204, the materials listed in the description of the planar type can be similarly used. For the step forming member 1206, an electrically insulating material such as SiO ₂ is used.

Next, a method for manufacturing a vertical surface conduction electron-emitting device will be described. FIGS. 14A to 14F are cross-sectional views for explaining a manufacturing process.
Same as 3.

1) First, as shown in FIG. 14A, an element electrode 1203 is formed on a substrate 1201.

2) Next, as shown in FIG. 13B, an insulating layer for forming a step forming member is laminated. The insulating layer may be formed by stacking, for example, SiO ₂ by a sputtering method, but another film forming method such as a vacuum evaporation method or a printing method may be used.

3) Next, as shown in FIG. 13C, an element electrode 1202 is formed on the insulating layer.

4) Next, as shown in FIG. 14D, a part of the insulating layer is removed by using, for example, an etching method to expose the element electrode 1203.

5) Next, as shown in FIG. 17E, a conductive thin film 1204 using a fine particle film is formed. For the formation, as in the case of the flat type, a film forming technique such as a coating method may be used.

6) Next, similarly to the case of the flat type, the energization forming process is performed to form an electron emission portion (the same process as the flat type energization forming process described with reference to FIG. 10C). Just do it.)

7) Next, similarly to the case of the above-mentioned flat type, an energization activation process is performed to deposit carbon or a carbon compound in the vicinity of the electron emitting portion (the flat type energizing described with reference to FIG. 10D). The same processing as the activation processing may be performed.)

As described above, the vertical surface conduction electron-emitting device shown in FIG. 14F was manufactured.

(Characteristics of Surface Conduction Emission Element Used in Display Device) The element structure and manufacturing method of the planar type and the vertical type surface conduction type emission element have been described above. Next, the characteristics of the element used in the display device will be described. Is described.

FIG. 15 shows typical examples of (emission current Ie) versus (element applied voltage Vf) characteristics and (element current If) versus (element applied voltage Vf) characteristics of the elements used in the display device. . Note that the emission current Ie is significantly smaller than the element current If, and it is difficult to show the same current on the same scale.
Since these characteristics are changed by changing design parameters such as the size and shape of the element, the two graphs are shown in arbitrary units.

The element used in the display device has the following three characteristics regarding the emission current Ie.

First, a certain voltage (this is referred to as a threshold voltage Vth
The emission current Ie sharply increases when a voltage having the above magnitude is applied to the element, but the emission current Ie is hardly detected at a voltage lower than the threshold voltage Vth.

That is, the non-linear element has a clear threshold voltage Vth with respect to the emission current Ie.

Secondly, since the emission current Ie changes depending on the voltage Vf applied to the element, the emission current Ie depends on the voltage Vf.
The magnitude of e can be controlled.

Third, since the response speed of the current Ie emitted from the element is faster than the voltage Vf applied to the element, the amount of charge of the electrons emitted from the element depends on the length of time during which the voltage Vf is applied. Can control.

Because of the above characteristics, the surface conduction electron-emitting device can be suitably used for a display device. For example, in a display device in which a large number of elements are provided corresponding to pixels of a display screen, if the first characteristic is used, display can be performed by sequentially scanning the display screen. That is,
The driving element has a threshold voltage Vt according to a desired light emission luminance.
h or higher, and a voltage lower than the threshold voltage Vth is applied to the non-selected elements. By sequentially switching the elements to be driven, the display screen can be sequentially scanned and displayed.

Further, since the emission luminance can be controlled by using the second characteristic or the third characteristic, gradation display can be performed.

(Structure of a Multi-Electron Beam Source in Which Many Devices are Wired in a Simple Matrix) Next, the structure of a multi-electron beam source in which the above-described surface conduction electron-emitting devices are arranged on a substrate and wired in a simple matrix will be described.

FIG. 4 is a plan view of the multi-electron beam source used for the display panel of FIG. On the substrate, surface conduction type emission elements similar to those shown in FIG. 9 are arranged, and these elements are wired in a simple matrix by row-direction wiring electrodes 1003 and column-direction wiring electrodes 1004. An insulating layer (not shown) is formed between the electrodes at the intersections of the row wiring electrodes 1003 and the column wiring electrodes 1004, so that electrical insulation is maintained.

FIG. 5 shows a cross section along the line AA 'in FIG.

The multi-electron source having such a structure is as follows.
After the row direction wiring electrode 1003, the column direction wiring electrode 1004, the interelectrode insulating layer (not shown), the device electrode of the surface conduction electron-emitting device and the conductive thin film are formed on the substrate in advance, the row direction wiring electrode 1003 and the column direction are formed. The device was manufactured by supplying current to each element via the wiring electrode 1004 and performing an energization forming process and an energization activation process.

(4) Driving Circuit Configuration (and Driving Method) FIG. 16 is a block diagram showing a schematic configuration of a driving circuit for performing television display based on an NTSC television signal. In the figure, a display panel 1701 corresponds to the above-described display panel, and is manufactured and operates as described above. The scanning circuit 1702 scans a display line, and the control circuit 1703 generates a signal to be input to the scanning circuit. The shift register 1704 shifts data for each line, and the line memory 1705 inputs the data for one line from the shift register 1704 to the modulation signal generator 1707. The synchronization signal separation circuit 1706 separates the synchronization signal from the NTSC signal.

Hereinafter, the function of each unit of the apparatus shown in FIG. 16 will be described in detail.

First, the display panel 1701 is connected to an external electric circuit via terminals Dx1 to Dxm, terminals Dy1 to Dyn, and a high voltage terminal Hv. The terminals Dx1 to Dxm are connected to the display panel 17
A scanning signal is applied to sequentially drive the multi-electron beam sources provided in 01, that is, the cold-cathode elements arranged in a matrix of m rows and n columns in a row (n elements). On the other hand, to the terminals Dy1 to Dyn, a modulation signal for controlling the output electron beams of the n elements for one row selected by the scanning signal is applied. Also,
The high voltage terminal Hv is connected to a DC voltage source Va, for example, 5
A DC voltage of [kV] is supplied, which is an accelerating voltage for applying sufficient energy to the electron beam output from the multi-electron beam source to excite the phosphor.

Next, the scanning circuit 1702 will be described. This circuit has m switching elements inside (in the figure,
S1 to Sm), each switching element selects either the output voltage of the DC voltage source Vx or 0 [V] (ground level), and the switching element of the display panel 1701 Terminals Dx1 to Dxm
It is electrically connected to. Each of the switching elements S1 to Sm operates based on the control signal Tscan output from the control circuit 1703. However, in practice, it can be easily configured by combining switching elements such as FETs. . The DC voltage source Vx outputs a constant voltage so that a driving voltage applied to an unscanned element is equal to or lower than an electron emission threshold voltage Vth based on the characteristics of the electron emission element illustrated in FIG. Is set to

The control circuit 1703 has a function of coordinating the operation of each section so that appropriate display is performed based on an image signal input from the outside. Based on a synchronizing signal Tsync sent from a synchronizing signal separating circuit 1706 to be described next, control signals Tscan, Tsft and Tmry are generated for each unit. The synchronizing signal separating circuit 1706 is a circuit for separating a synchronizing signal component and a luminance signal component from an NTSC system television signal input from the outside. As is well known, a frequency separating (filter) circuit is used. It can be easily configured. The synchronization signal separated by the synchronization signal separation circuit 1706 is composed of a vertical synchronization signal and a horizontal synchronization signal as is well known, but is shown here as a Tsync signal for convenience of explanation. On the other hand, a luminance signal component of an image separated from the television signal is referred to as a DATA signal for convenience, and this signal is input to a shift register 1704.

A shift register 1704 is for serially / parallel-converting the DATA signal input serially in time series for each line of an image, and is based on a control signal Tsft sent from the control circuit 1703. Works. That is, the control signal Tsft can be rephrased as a shift clock of the shift register 1704. The data for one line of the serial / parallel-converted image (corresponding to drive data for n electron-emitting devices) is output from the shift register 1704 as n signals Id1 to Idn.

The line memory 1705 is a storage device for storing data for one line of an image for a required time, and stores the contents of Id1 to Idn as appropriate according to a control signal Tmry sent from the control circuit 1703. The stored contents are output as I'd1 to I'dn and input to the modulation signal generator 1707.

The modulation signal generator 1707 controls the electron-emitting device 1 in accordance with each of the image data I'd1 to I'dn.
015 is a signal for appropriately driving and modulating each of the signals.
01 is applied to the electron-emitting device 1015.

As described with reference to FIG. 15, the surface conduction electron-emitting device according to the present invention has the following basic characteristics with respect to the emission current Ie. That is, electron emission has a clear threshold voltage Vth (8 [V] in a surface conduction electron-emitting device of an embodiment described later), and electron emission occurs only when a voltage equal to or higher than the threshold Vth is applied. Also, the electron emission threshold V
For a voltage equal to or greater than th, the emission current Ie also changes according to the change in the voltage, as shown in the graph of FIG. For this reason, when a pulse-like voltage is applied to the device, for example, when a voltage equal to or lower than the electron emission threshold Vth is applied, no electron emission occurs. An electron beam is output from the conduction type emission device. At this time, the intensity of the output electron beam can be controlled by changing the pulse peak value Vm.
In addition, it is possible to control the total amount of charges of the output electron beam by changing the pulse width Pw.

Therefore, a voltage modulation method, a pulse width modulation method, or the like can be adopted as a method of modulating the electron-emitting device in accordance with the input signal. When performing the voltage modulation method, a circuit of the voltage modulation method that generates a voltage pulse of a fixed length and modulates the peak value of the pulse appropriately according to input data is used as the modulation signal generator 1707. be able to. When implementing the pulse width modulation method, the modulation signal generator 1707 generates a voltage pulse having a constant peak value and modulates the width of the voltage pulse appropriately according to input data. Circuit can be used.

The shift register 1704 and the line memory 1
705 can be a digital signal type or an analog signal type. That is, the serial /
This is because parallel conversion and storage may be performed at a predetermined speed.

When the digital signal type is used, the output signal DATA of the synchronization signal separation circuit 1706 needs to be converted into a digital signal.
An A / D converter may be provided at the output unit 6. In this connection, the circuit used for the modulation signal generator differs slightly depending on whether the output signal of the line memory 115 is a digital signal or an analog signal. That is, in the case of the voltage modulation method using a digital signal, for example, a D / A conversion circuit is used as the modulation signal generator 1707, and an amplification circuit and the like are added as necessary. In the case of the pulse width modulation method, the modulation signal generator 1707 includes, for example, a high-speed oscillator, a counter (counter) for counting the number of waves output from the oscillator, and a comparator for comparing the output value of the counter with the output value of the memory. (Comparator) is used. If necessary, an amplifier for amplifying the pulse width modulated signal output from the comparator to the drive voltage of the electron-emitting device can be added.

In the case of the voltage modulation method using an analog signal, the modulation signal generator 1707 can employ an amplification circuit using, for example, an operational amplifier, and can add a shift level circuit and the like as necessary. In the case of the pulse width modulation method, for example, a voltage controlled oscillator (VCO)
And, if necessary, an amplifier for amplifying the voltage up to the drive voltage of the electron-emitting device can be added.

In the image display apparatus to which the present invention can be applied in such a configuration, by applying a voltage to each of the electron-emitting devices via terminals Dx1 to Dxm and Dy1 to Dyn outside the container, the electron-emitting device can emit electrons. Occurs. A high voltage is applied to the metal back 1019 or a transparent electrode (not shown) via the high voltage terminal Hv to accelerate the electron beam. The accelerated electrons collide with the fluorescent film 1018 and emit light to form an image.

The configuration of the image display apparatus described here is an example of an image forming apparatus to which the present invention can be applied, and various modifications can be made based on the concept of the present invention. The input signal is described in the NTSC system. However, the input signal is not limited to the NTSC system, but may be a PAL or SECAM system or a TV signal (MUSE system or other high-definition TV) system including a larger number of scanning lines. Can also be adopted.

[Case of Plate-shaped Spacer] FIG. 17 is a schematic perspective view showing another shape of the spacer on which the antistatic film of the present invention is formed, and FIG. 17 (a) corresponds to the position of each electron source. And a plate-like spacer having openings formed in a matrix. (B) shows a plate-like spacer similarly formed in a stripe shape.

[0169]

The present invention will be described in more detail with reference to the following examples.

(Example 1: High-resistance film) As an insulating member, a member obtained by forming a silicon nitride film on a surface of a soda lime glass by a 500 nm sputtering method was used.

On this insulating member, as a high-resistance thin film,
A Cr—Al alloy nitride film was formed by simultaneously sputtering Cr and Al targets with a high frequency power supply.
The sputtering gas is a mixed gas of Ar: N ₂ of 7: 3 and the total pressure is 4 mTorr. The high frequency power applied to the Cr and Al targets was adjusted so that the Cr was 5.8% and the specific resistance was 10
An alloy nitride film of ⁸ Ωcm or less was obtained.

Thus, a Cr—Al alloy nitride film having a specific resistance of 5 × 10 ⁵ Ωcm and a film thickness of 200 nm was formed as a high-resistance thin film.

Next, Al was formed in an island shape on the surface of this film by a sputtering method to obtain a sample A.

In order to form Al in an island shape, in the sputtering method, the power was set lower than usual and the sputtering was carried out for a short time. Thus, the Al conductive particles could be formed in an island shape as schematically shown in FIG.

In order to form a shape such that part of the Al particles enter the inside of the film as shown in FIG. 2, reverse sputtering (sputtering the substrate side) is performed, and then the substrate is heated. It was formed by performing low-power, short-time sputtering.

In order to form not only the island-like particles but also the island-like shape of the Al thin film, the sputtering time is shorter, the sputtering power is lower, and the pressure of the sputtering gas is lower than in normal film formation. Was formed by largely adjusting.

(Example 2: High resistance film) A Cr-Al alloy nitride film was formed on the same insulating member as in Example 1 under the same conditions, and had a specific resistance of 5 × 10 ⁵ Ωcm and a film thickness of 200 nm. C
An r-Al alloy nitride film was obtained. Next, on this surface, Ni was formed in an island shape by a sputtering method to obtain a sample B.

In order to form Ni in an island shape, in the sputtering method, the power was set lower than usual and the sputtering was carried out for a short time. As a result, an island-like shape composed of Ni conductive particles as shown in FIG. 1 could be produced.

Example 3 High Resistance Film A Cr—Al alloy nitride film was formed on the same insulating member as in Example 1 under the same conditions, and had a specific resistance of 5 × 10 ⁵ Ωcm and a thickness of 200 nm. C
An r-Al alloy nitride film was formed.

Next, Mo was formed in an island shape on the surface by sputtering using argon plasma to obtain a sample C.

In order to form an island shape, the same procedure as in Example 1 was performed. As a result, an island-like shape composed of Mo conductive particles as shown in FIG. 1 could be produced.

Example 4 High Resistance Film A Ti target was used in place of Cr in Example 1, and Ti—
An Al alloy nitride film was formed to a thickness of 60 nm. The sputtering gas was the same as in Example 1, and the high-frequency power of Ti and Al was adjusted to form an alloy nitride film having a specific resistance of 6 × 10 ⁴ Ωcm.
Sample D was obtained on the surface by continuously forming Ti in an island shape using the same device as the alloy nitride film.

In order to form an island shape, the same operation as in Example 1 was performed. Thereby, T as shown in FIG.
An island-like shape composed of the i conductive particles could be produced.

(Example 5: High resistance film) A Ta target was used in place of Cr in Example 1, and Ta-Al
An alloy nitride film was formed to a thickness of 80 nm. The sputtering gas was the same as in Example 1. The high frequency power of Ti and Al was adjusted to form an alloy nitride film having a specific resistance of 3 × 10 ³ Ωcm, and Ta was formed on the surface by sputtering using argon plasma. A sample E was obtained in the form of an island.

In order to form an island shape, the same operation as in Example 1 was performed. Thereby, T as shown in FIG.
Thus, an island-like shape composed of the conductive particles a was able to be produced.

[Results] Each of the samples A to E on which the antistatic film of the present invention was formed was heat-treated at 425 ° C.
When the resistance value after heat treatment at 200 ° C. in vacuum was measured, all of the antistatic films of the present invention were stable without any significant change.

That is, since the change in resistance of the antistatic film of the present invention is small even after the heat treatment, the use environment is vacuum as in an electron beam display, or a high-temperature heat treatment
It is particularly effective for applications involving vacuum heat treatment.

(Example 6: Spacer) A silicon nitride film was formed by a 0.5 μm sputtering method on a glass surface of the same quality as a rear plate having a length of 20 mm, a width of 5 mm and a thickness of 0.2 mm, and this was used as an insulating member. .

As the antistatic film, Cr used in Example 1 was used.
-An Al alloy nitride film having a thickness of 200 nm and Al formed in an island shape was used. The antistatic film of the present invention is not limited to this and can be used.

Next, as a low resistance film 1020c (FIG. 8),
An Au film having a thickness of 0.1 μm was formed in a 30 μm band shape in parallel with the connection portion between the face plate and the rear plate. The spacer is connected to the metal back on the X-direction wiring and the face plate using conductive frit glass. As the conductive frit glass, a mixture of frit glass and conductive fine particles whose surface is coated with gold is used, and is electrically connected to the antistatic film on the spacer surface and the X-directional wiring or face plate.

In the present embodiment, as the multi-electron beam source, N × M (N = 3072, M = 10
24) The surface conduction electron-emitting device is formed by combining M row-directional wirings and N
A multi-electron beam source with matrix wiring (see FIGS. 3 and 4) with the column-directional wiring was used.

In this example, a display panel on which the above-described spacer 1020 shown in FIG. 3 was arranged was manufactured. The details will be described below with reference to FIGS. First, a row direction wiring electrode 1013 and a column direction wiring electrode 101 are previously formed on a substrate.
4. The substrate 1011 on which the interelectrode insulating layer (not shown), the device electrode of the surface conduction electron-emitting device and the conductive thin film are formed,
It was fixed to the rear plate 1015.

Next, the surface of the insulating member 1020a made of soda lime glass, which is exposed in the airtight container,
A high resistance film 1020b described later is formed on the surface, and a conductive film 1020c is formed on the contact surface.
m], plate thickness 200 [micrometer], length 20 m
m) was fixed on the row direction wiring 1013 of the substrate 1011 at regular intervals and in parallel with the row direction wiring 1013.

Thereafter, a face plate 1017 having a fluorescent film 1018 and a metal back 1019 on its inner surface is disposed 5 mm above the substrate 1011 via a side wall 1016, and the rear plate 1015, the face plate 101
7. The joints of the side wall 1016 and the spacer 1020 were fixed. The joint between the substrate 1011 and the rear plate 1015, the joint between the rear plate 1015 and the side wall 1016, and the joint between the face plate 1017 and the 10 side wall 1016 are coated with frit glass (not shown), and are heated to 400 ° C. to 500 ° C. It sealed by baking at ℃ for 10 minutes or more.

The spacer 1020 is formed on the substrate 1011.
A conductive frit glass (not shown) mixed with a conductive material such as a conductive filler or metal is provided on the row wiring 1013 (line width 300 [micrometer]) on the side and on the metal back 1019 surface on the face plate 1017 side. ) And fired at 400 ° C. to 500 ° C. for 10 minutes or more in the air at the same time as the sealing of the airtight container, thereby bonding and electrically connecting.

In this embodiment, the fluorescent film 101 is used.
As shown in FIG. 6, each of the phosphors 8 adopts a stripe shape in which each color phosphor 21a extends in the column direction (Y direction), and the black conductor 21b is not only between each color phosphor (R, G, B) 21a. , A fluorescent film arranged so as to separate each pixel in the Y direction is used, and the spacer 1020 is a black conductor 21b region (line width 300 [micrometer]) parallel to the row direction (X direction). It was arranged via a metal back 1019 inside. When the above-mentioned sealing is performed, each color phosphor 21a must correspond to each element arranged on the substrate 1011. Therefore, the rear plate 1015, the face plate 1017, and the spacer 1020 are located at a sufficient position. Matching was performed.

The inside of the airtight container completed as described above is evacuated by a vacuum pump through an exhaust pipe (not shown), and after reaching a sufficient degree of vacuum, the outer terminals Dx1 to Dxm and Dy1 to Dx1.
A multi-electron beam source was manufactured by supplying power to each element through the Dyn through the row direction wiring electrode 1013 and the column direction wiring electrode 1014 to perform the above-described energization forming process and energization activation process.

Next, the envelope (airtight container) welded by heating an exhaust pipe (not shown) with a gas burner at a degree of vacuum of about 10 −6 [Torr].

Finally, a getter process was performed to maintain the degree of vacuum after sealing.

In the image display device using the display panel as shown in FIGS. 3 and 7 completed as described above, each cold cathode element (surface conduction type emission element) 1012 has external terminals Dx1 to Dx1. A scanning signal and a modulation signal are applied from Dxm and Dy1 to Dyn by a signal generation unit (not shown) to emit electrons, and an emitted electron beam is applied to the metal back 1019 by applying a high voltage through a high voltage terminal Hv. Accelerates the fluorescent film 1018
To each color phosphor 21a (R, G,
An image was displayed by exciting and emitting B). In addition,
The applied voltage Va to the high voltage terminal Hv is 3 [kV] to 10 [kV].
[KV], the applied voltage V between the wirings 1013 and 1014
f was set to 14 [V].

At this time, a two-dimensional array of light-emitting spots including light-emitting spots generated by electrons emitted from the cold cathode elements 1012 located near the spacer 1020 is formed at two-dimensional intervals, and a clear color image with good color reproducibility is obtained. Display was completed.
This indicates that even when the spacer 1020 was provided, no electric field disturbance affecting the electron trajectory occurred.

[0202]

As described above , according to the present invention,
By forming a high-resistance film on the surface of the insulating member and dispersing the conductive fine particles discretely in an island shape, a sufficient antistatic effect is obtained, and an image form having a highly stable antistatic film is obtained.
An apparatus was obtained .

Further, by applying this antistatic film to the surface of the spacer that supports the internal space of the image display device, the disturbance of the beam near the spacer is suppressed, and the position where the beam collides with the phosphor and the original light emission is obtained. It is possible to prevent the occurrence of a positional shift from the fluorescent material to be prevented, prevent loss of luminance, and manufacture a display device capable of displaying a clear image.

That is, the image forming apparatus of the present invention
The antistatic film has a small change in resistance even after heat treatment, so the environment in which it is used is a vacuum like an electron beam display,
This is particularly effective for applications that include high-temperature heat treatment and vacuum heat treatment in the manufacturing process.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an antistatic film according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view of an antistatic film according to another embodiment of the present invention.

FIG. 3 is a perspective view of the image display device according to the embodiment of the present invention, in which a part of a display panel is cut away.

FIG. 4 is a plan view of a substrate of the multi-electron beam source used in the embodiment.

FIG. 5 is a partial cross-sectional view of a substrate of the multi-electron beam source used in the embodiment.

FIG. 6 is a plan view illustrating a phosphor array of a face plate of the display panel.

FIG. 7 is a sectional view taken along the line AA ′ of the display panel according to the embodiment of the present invention.

FIG. 8 is a sectional view of a spacer of the image display device of the present invention.

FIGS. 9A and 9B are a plan view and a cross-sectional view, respectively, of a planar surface conduction electron-emitting device used in an example.

FIG. 10 is a cross-sectional view showing a manufacturing process of the planar surface conduction electron-emitting device.

FIG. 11 is an applied voltage waveform in the energization forming process.

FIG. 12 shows an applied voltage waveform (a) during energization activation processing;
Change in emission current Ie (b).

FIG. 13 is a sectional view of a vertical surface conduction electron-emitting device used in an example.

FIG. 14 is a sectional view showing a manufacturing process of the vertical surface conduction electron-emitting device.

FIG. 15 is a graph showing typical characteristics of the surface conduction electron-emitting device used in the example.

FIG. 16 is a block diagram illustrating a schematic configuration of a driving circuit of the image display device according to the embodiment of the invention.

FIG. 17 is a schematic perspective view showing the shape of another spacer.

FIG. 18 shows an example of a conventionally known surface conduction electron-emitting device.

FIG. 19 shows an example of a conventionally known FE element.

FIG. 20 shows an example of a conventionally known MIM type device.

FIG. 21 is a perspective view of the display panel of the image display device with a part thereof cut away.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulating member 2 Antistatic film 3 High resistance thin film 4 Conductive particle 1020 Spacer

Continuation of front page (56) References JP-A-8-180821 (JP, A) JP-A-8-250032 (JP, A) JP-A-11-73897 (JP, A) JP-A-3-275534 (JP) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H05F 1/02 H01J 29/87 H01J 31/12

Claims (9)

(57) [Claims] 1. An image forming apparatus having an electron source and an image forming member for forming an image by electrons generated from the electron source, wherein a high resistance is provided on a surface of a supporting member for supporting an image forming space inside the device. A thin film and an island formed on the high resistance thin film
An image forming apparatus , wherein an antistatic film having conductive fine particles is formed. 2. The image forming apparatus according to claim 1, wherein the island-shaped conductive particles are provided in and on the high-resistance thin film. Wherein said conductive particles, the field of claim 1, wherein that the thin film formed on the island-shaped
Image forming device . 4. The high-resistance thin film has a thickness of 0.1 to 10 ⁸ [Ω].
cm].
The image forming apparatus according to any one of the above. 5. The high-resistance thin film according to claim 1, wherein the high-resistance thin film is any one of oxides of Cr, Ni, and Cu, and a nitride of an alloy of a transition metal and Al. An image forming apparatus according to claim 1 . 6. The island-shaped conductive particles are B
e, Mg, Al, Ti, Ni, Cs, Ba, Pt, A
u, Ag, Rh, Ir, Sb, Sn, Pb, Ga, Z
n, In, Cd, Cu, Co, Rh, Fe, Mn, C
r, V, Zr, Nb, Mo, W of the metal and a plurality of said formed of a metal alloy, SnO ₂ oxide, claim, characterized in that any one of a sulfide of MoS _2, WS ₂ 1 to 5
The image forming apparatus according to any one of the above. Wherein said support member is an image forming apparatus according to claim 1, characterized in that the spacer. Wherein said support member, serial <br/> placing the image forming apparatus to claim 1, characterized in that a side wall of the image forming space. Wherein said electron source, an image forming apparatus according to claim 1, characterized in that it consists of a surface conduction electron-emitting devices.