JP3428806B2 - Electron emitting element, electron source substrate, and method of manufacturing image forming apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface conduction electron-emitting device, an electron source substrate, and a method for manufacturing an image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, there are known two types of electron-emitting devices, which are roughly classified into a thermoelectron-emitting device and a cold cathode electron-emitting device. Cold cathode electron emission devices include field emission type (hereinafter referred to as “FE type”), metal / insulating layer / metal type (hereinafter referred to as “MIM type”), surface conduction type electron emission devices, and the like. An example of the FE type is "WP Dyke &
W. W. Doran, "Field Emissio"
n ”, Advance in Electron Phy
sics, 8, 89 (1956) "or C.I. A. S
pindt "Physical Properties"
of thin-film field emiss
ion cathodes with mollybde
nium cones ”, J. Appl. Phys.,
47, 5248 (1976) and the like are known. For the MIM type, C.I. A. Mead, “Ope
relation of Tunnel-Emission
Devices ", J. Appl. Phys., 3
2, 646 (1961) and the like are known. In the surface conduction electron-emitting device, electrons are emitted by passing a current through a thin film of a small area formed on a substrate in parallel with the film surface. As the surface conduction electron-emitting device, one using a SnO ₂ thin film by the above-mentioned Erinson, one using an Au thin film (G. Dittmer: Thi
n Solid Films, 9, 317 (197)
2)), by In ₂ O ₃ / SnO ₂ thin film (MH
artwell and C.I. G. Fonstad: I
EEE Trans. ED Conf. , 519 (19
75)), a carbon thin film (Hiraki Araki et al .: Vacuum, Vol. 26, No. 1, p. 22 (1983))) and the like.

As a typical example of these surface conduction electron-emitting devices, the above-mentioned M. Figure 12 shows the Hartwell device configuration.
Is schematically shown in. In the figure, 1 is a substrate. Reference numeral 4 denotes a conductive thin film, which is composed of a metal oxide thin film or the like formed by sputtering in an H-shaped pattern, and the electron emission portion 5 is formed by an energization process called energization forming described later.
The element electrode spacing L1 in the figure is set to 0.5 to 1 mm, and W'is set to 0.1 mm.

Conventionally, in these surface conduction electron-emitting devices, it is general that the electron-emitting portion 5 is formed by subjecting the conductive thin film 4 to an energization process called energization forming in advance before the electron emission. It was That is, the energization forming means that a direct current voltage or a very slow rising voltage is applied to both ends of the electroconductive thin film 4 to energize the electroconductive thin film to locally break, deform or alter the electroconductive thin film to a high electrical resistance state. That is, the electron emitting portion 5 is formed.
In the electron emitting portion 5, a crack is generated in a part of the conductive thin film 4, and electrons are emitted from the vicinity of the crack. In the surface conduction electron-emitting device that has been subjected to the energization forming process, a voltage is applied to the conductive thin film 4 and a current is passed through the device so that electrons are emitted from the electron-emitting portion 5.

[0005]

Since the surface conduction electron-emitting device described above has a simple structure and is easy to manufacture, there is an advantage that a large number of devices can be arrayed over a large area. Therefore, applied research on charged beam sources, display devices, and the like, which make use of this feature, has been conducted. As an example in which a large number of surface conduction electron-emitting devices are formed in an array, as will be described later, surface conduction electron-emission devices are arranged in parallel called a ladder arrangement, and both ends of each device are wired (also called common wiring). , An electron source in which a large number of connected lines are arranged (see, for example, Japanese Patent Laid-Open No. Sho 6-66).
4-031332, JP-A-1-283749, 2-25
7552). Further, in particular, in image forming apparatuses such as display devices, in recent years, flat panel display devices using liquid crystal have been used in CRTs.
However, since it is not a self-luminous type, there is a problem that it is necessary to have a backlight, etc. Therefore, development of a self-luminous display device has been desired. An example of the self-luminous display device is an image forming device which is a display device in which a plurality of surface conduction electron-emitting devices are arranged and a phosphor that emits visible light by electrons emitted from the electron source is combined. For example, USP 5066883).

The rear panel of a display using these surface conduction electron-emitting devices was manufactured by using a thin film process, but in the thin film process, the number of steps was large and the cost was very high due to the large area. .

On the other hand, it has been attempted to use a printing process such as screen printing to prepare an electron source substrate. However, since the device electrodes apply a uniform voltage to the electron-emitting devices, the edges of the electrodes are smooth. It is preferable that the film thickness is uniform. However, when printing on a screen, etc., the edges of the electrodes may not be smooth, or if the film quality is porous and the device is applied in a liquid state, it may be absorbed by the electrodes, resulting in large variations in device characteristics. A display using a surface conduction electron-emitting device using the manufacturing method may have a low manufacturing yield.

In view of the problems of the prior art, it is an object of the present invention to provide a method of manufacturing an electron source substrate capable of forming a device electrode which solves the above problems by a printing method.

[0009]

To achieve this object, the present invention comprises at least a pair of device electrodes on an insulating substrate and a thin film provided between the device electrodes and including an electron emitting portion. In the method of manufacturing a surface conduction electron-emitting device, and the method of manufacturing an electron source substrate and an image forming apparatus using this method, the step of forming the element electrode is performed by printing the element electrode on the insulating substrate. The step of forming a device electrode pattern having a porous surface with the above material, the step of subjecting the insulating substrate on which the element electrode pattern is formed to a hydrophobic treatment, and the step of applying the hydrophobic treatment, and then applying a metal-containing solution to the element electrode pattern . And firing.

That is, first, element electrodes are formed on a substrate by a screen printing method or an offset printing method. In the electrodes formed by these printing methods, the edges may not be smooth, or the surface may be porous, and the organic solvent in the element forming step may be sucked. Therefore, next, a hydrophobic treatment agent is applied to this substrate using a dipping method or the like,
The gap portion such as the SiO ₂ surface is made a hydrophobic surface. Then, a metal-containing solution is applied to this substrate by using a dipping method, an inkjet method, or the like. Then, the metal-containing solution is repelled on the hydrophobic surface, and droplets are provided on the device electrodes. When this substrate is fired, it is possible to form a device electrode film which has a smooth edge portion, is not porous, and has less suction.

As a result, in the device electrode manufactured by this manufacturing method, it is possible to reduce variations in device characteristics.
Furthermore, in this manufacturing method, the metal-containing solution is applied by self-alignment after the electrodes are formed by the printing method without using the photolithography process, so the manufacturing cost is low.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

First, the planar surface conduction electron-emitting device will be described. 2A and 2B are schematic diagrams showing the configuration of a flat surface conduction electron-emitting device according to an embodiment of the present invention, FIG. 2A being a plan view and FIG. 2B being a cross-sectional view.
In FIG. 2, 1 is a substrate, 2 and 3 are device electrodes, 4 is a conductive thin film, and 5 is an electron emitting portion.

As the substrate 1, quartz glass, glass having a reduced content of impurities such as Na, soda lime glass, a glass substrate having SiO ₂ deposited by a sputtering method, a ceramics substrate such as alumina, and the like can be used. .

The material of the opposing device electrodes 2 and 3 is as follows:
Common conductive materials can be used, such as Ni, Cr, A
Metals or alloys such as u, Mo, W, Pt, Ti, Al, Cu, Pd and Pd, As, Ag, Au, RuO ₂ , P
It can be selected from a printed conductor composed of a metal such as d-Ag or a metal oxide and glass, a transparent conductor such as In ₂ O ₃ —SnO ₂ and a semiconductor conductor material such as polysilicon.

The element electrode interval L1, the element electrode length W2, the shape of the conductive thin film 4 and the like are determined in consideration of the applied form.
Designed. The device electrode spacing L1 is preferably in the range of several thousand angstroms to several hundreds of micrometers,
More preferably, it is in the range of 1 μm to 100 μm in consideration of the voltage applied between the device electrodes. The device electrode length W2 is in the range of several micrometers to several hundred micrometers in consideration of the resistance value of the electrode and electron emission characteristics. The film thickness d of the device electrodes 2 and 3 is 1
The range is from 00 angstroms to 1 micrometer. In addition to the configuration shown in FIG.
Alternatively, the conductive thin film 4 and the opposing device electrodes 2 and 3 may be laminated in this order.

For the conductive thin film 4, it is preferable to use a fine particle film composed of fine particles in order to obtain good electron emission characteristics. The film thickness is appropriately set in consideration of the step coverage to the device electrodes 2 and 3, the resistance value between the device electrodes 2 and 3 and the forming conditions described later, but usually it is in the range of several angstroms to several thousand angstroms. Is more preferable, and more preferably in the range of 10 angstroms to 500 angstroms. The resistance value is such that R _S is 10 2 to 10 7 Ω. Note that R _S is a value that appears when the resistance R of a thin film having a thickness of t, a width of w and a length of 1 is R = R _S (l / w), and the resistivity of the thin film material is ρ. Then R _S = ρ
It is represented by / t. Here, the forming process will be described by taking an energization process as an example, but the forming process is not limited to this, and any method may be used as long as it is a method of forming a crack in a film to form a high resistance state.

The materials forming the conductive thin film 4 are Pd and P.
t, Ru, Ag, Au, Ti, In, Cu, Cr, F
e, Zn, Sn, Ta, W, Pb and other metals, PdO, S
oxides such as nO ₂ , In ₂ O ₃ , PbO and Sb ₂ O ₃ ;
HfB ₂ , ZrB ₂ , LaB ₆ , CeB ₆ , YB ₄ , G
Borides such as dB ₄ , TiC, ZrC, HfC, TaC,
It is appropriately selected from carbides such as SiC and WC, nitrides such as TiN, ZrN and HfN, semiconductors such as Si and Ge, and carbon.

The fine particle film described here is a film in which a plurality of fine particles are aggregated, and its fine structure has a state in which the fine particles are individually dispersed and arranged, or a state in which the fine particles are adjacent to each other or overlap each other (some fine particles are aggregated). However, it also includes the case where an island-shaped structure is formed as a whole). The particle size of the fine particles is several angstroms or 1 μm
Range, preferably 10 Angstroms to 200
It is in the Angstrom range.

The electron emitting portion 5 is composed of a crack having a high resistance formed in a part of the conductive thin film 4, and depends on the film thickness, film quality, material of the conductive thin film 4 and a method such as energization forming described later. It will be what you did. The inside of the electron emitting portion 5 may contain conductive fine particles having a particle diameter of 1000 angstroms or less. The conductive fine particles contain some or all of the elements of the material forming the conductive thin film 4. The electron emitting portion 5 and the conductive thin film 4 in the vicinity thereof may contain carbon or a carbon compound.

An example of the manufacturing method will be described below with reference to FIGS. 1 and 3, the same parts as those shown in FIG. 2 are designated by the same reference numerals as those shown in FIG.

The substrate 1 is thoroughly washed with a detergent, pure water, an organic solvent or the like, and opposing element electrodes are formed by a screen printing method, an offset printing method or the like (FIG. 1).
(A)). The electrode at this time may not have a smooth edge portion, and the surface may be porous, and the organometallic solution in the subsequent element forming step may be sucked.

Next, a hydrophobic treatment agent such as a silane coupling agent is applied to the substrate 1 by a dipping method, a spinner method or the like using a mask or the like except for the element electrodes and then baked to make the glass surface of the substrate 1 hydrophobic. Face (FIG. 1 (b)).

Then, an organic metal-containing solution is applied to this substrate by a dipping method, an ink jet method or the like. Then, this solution is repelled on the glass substrate and applied only on the electrodes. After that, firing is performed (FIG. 1C). After firing, it is possible to form a device electrode having a smooth edge and a non-porous surface without changing the distance between the gaps.

An organic metal solution is applied to the substrate 1 provided with the device electrodes 2 and 3 to form an organic metal thin film. As the organic metal solution, a solution of an organic metal compound containing a metal of the material of the conductive thin film 4 as a main element can be used. The organic metal thin film is heat-fired and patterned by lift-off, etching or the like to form the conductive thin film 4 (FIG. 3B). Although the method of applying the organic metal solution has been described here, the method of forming the conductive thin film 4 is not limited to this, and a vacuum deposition method, a sputtering method, a chemical vapor deposition method, a dispersion coating method, A dipping method, a spinner method, an inkjet method or the like can also be used.

Subsequently, a forming process is performed. As an example of this forming processing method, a method based on energization processing will be described. When electricity is applied between the device electrodes 2 and 3 by using a power source (not shown), the electron emitting portion 5 having a changed structure is formed at the site of the conductive thin film 4 (FIG. 3C). According to the energization forming, a site having a structural change such as local destruction, deformation or alteration is formed in the conductive thin film 4. This portion becomes the electron emitting portion 5. An example of the voltage waveform of energization forming is shown in FIG.

The voltage waveform is preferably a pulse waveform. For this, the method shown in FIG. 5 (a) in which a pulse whose peak value is a constant voltage is continuously applied and the method shown in FIG. 5 (b) in which a voltage pulse is applied while increasing the pulse peak value are used. There is.

In FIG. 5A, T1 and T2 are the pulse width and pulse interval of the voltage waveform. Normally, T1 is set in the range of 1 microsecond to 10 milliseconds, and T2 is set in the range of 10 microseconds to 100 milliseconds. The peak value of the triangular wave (peak voltage during energization forming) is appropriately selected according to the form of the surface conduction electron-emitting device. Under these conditions,
For example, the voltage is applied for several seconds to several tens of minutes. The pulse waveform is not limited to the triangular wave, and a desired waveform such as a rectangular wave can be adopted.

T1 and T2 in FIG. 5 (b) can be the same as those shown in FIG. 5 (a). The peak value of the triangular wave (peak voltage during energization forming) can be increased by, for example, about 0.1 V step.

The end of the energization forming process can be detected by applying a voltage that does not locally break or deform the conductive thin film 4 during the pulse interval T2 and measure the current. For example, the device current flowing by applying a voltage of about 0.1 V is measured, the resistance value is obtained, and the energization forming is terminated when the resistance of 1 M ohm or more is shown.

It is preferable that an activation treatment is applied to the element which has finished forming. By applying the activation process,
The device current If and the emission current Ie change remarkably. The activation treatment is performed, for example, in an atmosphere containing a gas of an organic substance,
Similar to the energization forming, it can be performed by repeating the application of the pulse. This atmosphere can be formed by utilizing the organic gas remaining in the atmosphere when the inside of the vacuum container is evacuated by using, for example, an oil diffusion pump or a rotary pump, and is sufficiently evacuated once by an ion pump or the like. It can also be obtained by introducing a gas of a suitable organic substance into a vacuum. The preferable gas pressure of the organic substance at this time is different depending on the form of application, the shape of the vacuum container, the type of the organic substance, and the like, and is appropriately set depending on the case.
Suitable organic substances include alkanes, alkenes, alkyne aliphatic hydrocarbons, aromatic hydrocarbons, alcohols, aldehydes, ketones, amines, phenols,
Examples thereof include organic acids such as carboxylic acid and sulfonic acid. Specifically, methane, ethane, propane and the like C _n H
Saturated hydrocarbon represented by _{2n + 2,} unsaturated hydrocarbons represented by the composition formula and propylene such as C _n H _2n, benzene, toluene, methanol, ethanol, formaldehyde, acetaldehyde, acetone, methyl ethyl ketone, methyl amine , Ethylamine, phenol, formic acid,
Acetic acid, propionic acid, etc. can be used. By this treatment, carbon or a carbon compound is deposited on the element from the organic substance existing in the atmosphere, and the element current If and the emission current Ie are significantly changed. The termination of the activation process is determined while measuring the device current If and the emission current Ie. The pulse width, pulse interval, pulse crest value, etc. are set appropriately.

As carbon or carbon compound, HOP
G (Highly Oriented Pyrolytic Graphite), PG (Py
Graphites such as rolytic Graphite) and GC (Glassy Carbon) are included. (HOPG is a graphite with a nearly perfect crystal structure, PG is a graphite with a crystal grain of about 200 Å and the crystal structure is slightly disordered, and GC is a crystal grain with 2 crystal grains.
It means that the disorder of the crystal structure became even larger at about 0Å. ) Or amorphous carbon (amorphous carbon and carbon containing a mixture of amorphous carbon and fine crystals of graphite), and its film thickness is preferably 500 angstroms or less, and more preferably 300 angstroms or less. .

The electron-emitting device obtained through the activation process is preferably subjected to stabilization treatment. In this treatment, the partial pressure of the organic substance in the vacuum container is 1 × 10 ⁻⁸ Torr or less,
Desirably, it is performed at 1 × 10 ⁻¹⁰ Torr or less.
The pressure in the vacuum container is preferably 10 ⁻⁶ to 10 ⁻⁷ torr, and particularly preferably 1 × 10 ⁻⁸ torr or less. It is preferable to use a vacuum evacuation device that evacuates the vacuum container without using oil so that the oil generated from the device does not affect the characteristics of the element. Specifically, a vacuum evacuation device such as a sorption pump or an ion pump can be used. Further, when evacuating the inside of the vacuum container, it is preferable to heat the entire vacuum container so that organic substance molecules adsorbed on the inner wall of the vacuum container and the electron-emitting device can be easily exhausted.
The vacuum evacuation condition in the heated state at this time is 80 to 2
It is desirable that the temperature is 00 ° C. for 5 hours or more, but the condition is not particularly limited to this condition, and may vary depending on various conditions such as the size and shape of the vacuum container and the configuration of the electron-emitting device. The partial pressure of the organic substance is measured by a mass spectrometer with a mass number of 10 to 20.
It is obtained by measuring the partial pressure of an organic molecule containing 0 and carbon and hydrogen as main components and integrating the partial pressures.

It is preferable to maintain the atmosphere at the time of driving after the stabilization step is the atmosphere at the time of completion of the above-mentioned stabilization process, but the present invention is not limited to this, and if the organic substance is sufficiently removed, Even if the degree of vacuum itself is slightly lowered, it is possible to maintain sufficiently stable characteristics.

By adopting such a vacuum atmosphere, the deposition of new carbon or carbon compound can be suppressed,
As a result, the device current If and the emission current Ie are stabilized.

Various arrangements of electron-emitting devices can be adopted. As an example, a large number of electron-emitting devices arranged in parallel are connected at both ends, and a large number of rows of electron-emitting devices are arranged (referred to as a row direction), and in a direction orthogonal to this wiring (referred to as a column direction). There is a ladder-like arrangement in which a control electrode (also referred to as a grid) arranged above the electron-emitting device controls and drives electrons from the electron-emitting device. Separately, a plurality of electron-emitting devices are arranged in a matrix in the X and Y directions, and one of electrodes of the plurality of electron-emitting devices arranged in the same row is commonly connected to a wiring in the X direction. For example, the other of the electrodes of the plurality of electron-emitting devices arranged in the same column is commonly connected to the wiring in the Y direction. This is a so-called simple matrix arrangement. First, the simple matrix arrangement will be described in detail below.

An electron source substrate obtained by arranging a plurality of electron-emitting devices in a matrix will be described with reference to FIG. In FIG. 6, 71 is an electron source substrate, 73 is an X-direction wiring, and 72 is a Y-direction wiring. Reference numeral 74 denotes an electron emitting portion of the surface conduction electron-emitting device.

The m X-direction wirings 73 are Dox1 and Dox1.
x2, ..., Doxm, vacuum deposition method, printing method,
It can be made of a conductive metal or the like formed by using a sputtering method or the like. The wiring material, film thickness, and width are appropriately designed. The Y-direction wiring 72 includes Doy1, Doy2, ...
It is composed of n Doyn wirings and is formed in the same manner as the X-direction wiring 73. These m X-direction wirings 73 and n Y-wirings
An interlayer insulating layer (not shown) is provided between the directional wiring 72 and the directional wiring 72 to electrically separate the two (m and n are both positive integers).

The interlayer insulating layer (not shown) is composed of SiO ₂ or the like formed by a vacuum deposition method, a printing method, a sputtering method or the like. For example, it is formed in a desired shape on the entire surface or a part of the substrate 71 on which the X-direction wiring 73 is formed, and in particular, the film thickness, material, The manufacturing method is set. X-direction wiring 73 and Y
The directional wirings 72 are respectively drawn out as external terminals.

Each pair of electrodes (not shown) forming the surface conduction electron-emitting device 74 has m X-direction wirings 73 and n Y electrodes.
The direction wiring 72 is electrically connected by a wire made of a conductive metal or the like. The material forming the wirings 72 and 73, the material forming the wiring, and the material forming the pair of element electrodes may be the same or different in some or all of the constituent elements. These materials are
For example, it is appropriately selected from the above-mentioned material of the device electrode. If the material forming the device electrodes and the wiring material are the same,
The wiring connected to the device electrode can also be called a device electrode.

A scanning signal applying means (not shown) for applying a scanning signal for selecting a row of surface conduction electron-emitting devices arranged in the X direction is connected to the X-direction wiring 73. On the other hand, Y
The directional wiring 72 is connected to a modulation signal generating means (not shown) for modulating each column of the surface conduction electron-emitting devices arranged in the Y direction according to an input signal. The driving voltage applied to each electron-emitting device is supplied as a difference voltage between the scanning signal and the modulation signal applied to the device.

In the above structure, individual elements can be selected and driven independently by using simple matrix wiring.

An image forming apparatus constructed by using an electron source having such a simple matrix arrangement will be described with reference to FIGS. 7, 8 and 9. 7 is a schematic diagram showing an example of a display panel of the image forming apparatus, and FIG. 8 is a schematic diagram of a fluorescent film used in the image forming apparatus of FIG. Figure 9 shows NTSC
It is a block diagram showing an example of a drive circuit for performing display according to a television signal of the system.

In FIG. 7, 71 is an electron source substrate on which a plurality of electron-emitting devices are arranged, 81 is a rear plate to which the electron source substrate 71 is fixed, and 86 is a glass substrate 83 on which a fluorescent film 84, a metal back 85 and the like are formed. It is a face plate. Reference numeral 82 denotes a support frame. The rear plate 81 and the face plate 86 are connected to the support frame 82 by using frit glass or the like. Reference numeral 88 denotes an envelope, for example, 1 in the temperature range of 400 to 500 ° C. in the atmosphere or nitrogen.
It is baked for 0 minutes or more and sealed. 74 corresponds to the electron emitting portion in FIG. Reference numerals 72 and 73 denote an X-direction wiring and a Y-direction wiring connected to the pair of device electrodes of each surface conduction electron-emitting device.

The envelope 88 is composed of the face plate 86, the support frame 82, and the rear plate 81 as described above. Since the rear plate 81 is provided mainly for the purpose of reinforcing the strength of the power supply substrate 71, if the electron source substrate 71 itself has sufficient strength, the separate rear plate 81 can be omitted. That is, the support frame 82 is directly sealed to the substrate 71, and the face plate 86, the support frame 82, and the substrate 71 are attached.
The envelope 88 may be configured with. On the other hand, by installing a support body (not shown) called a spacer (atmospheric pressure resistant support member) between the face plate 86 and the rear plate 81, the envelope 88 having sufficient strength against atmospheric pressure is configured. You can also do it.

FIG. 8 is a schematic view showing the fluorescent film 84.
In the case of monochrome, the fluorescent film 84 can be composed of only a phosphor. In the case of a color phosphor film, it can be composed of a black member 91 called a black stripe or a black matrix depending on the arrangement of the phosphors and a phosphor 92. In the case of color display, the purpose of providing the black stripes and the black matrix is to make the color-separated portion between the phosphors 92 of the three primary color phosphors black so as to make the color mixture inconspicuous and to contrast due to external light reflection. It is to suppress the decrease of. As the material of the black stripe, in addition to the commonly used material containing graphite as a main component, any material that transmits and reflects light little can be used.

As a method of applying the phosphor to the glass substrate 93, a precipitation method, a printing method or the like can be adopted regardless of monochrome or color. A metal back 85 is usually provided on the inner surface side of the fluorescent film 84. The purpose of providing a metal back is
Of the light emitted from the phosphor, the light emitted to the inner surface side is applied to the face plate 8
To improve the brightness by mirror-reflecting to the 6 side, to act as an electrode for applying an electron beam accelerating voltage, to protect the phosphor from damage due to collision of negative ions generated in the envelope, etc. Is. In the metal back, after the phosphor film is produced, the inner surface of the phosphor film is smoothed (usually called “filming”),
After that, Al can be produced by depositing Al using vacuum deposition or the like.

On the face plate 86, the fluorescent film 8 is further provided.
In order to improve the conductivity of No. 4, a transparent electrode (not shown) may be provided on the outer surface side (the glass substrate 83 side) of the fluorescent film 84. When the above-mentioned sealing is performed, in the case of color, it is necessary to associate each color phosphor with the electron-emitting device, and sufficient alignment is indispensable.

The display panel shown in FIG. 7 is manufactured, for example, as follows. Similar to the above-described stabilization process, the envelope 88 is appropriately heated and exhausted through an exhaust pipe (not shown) by an exhaust device that does not use oil, such as an ion pump or a sorption pump, and has a pressure of about 10 ⁻⁷ Torr. After making the atmosphere of a vacuum degree of a sufficiently small amount of an organic substance, it is sealed. In order to maintain the vacuum degree after the envelope 88 is sealed,
Getter processing can also be performed. This is the envelope 88
Immediately before or after the sealing of (1) or (2) is performed, the getter arranged at a predetermined position (not shown) in the envelope 88 is heated by heating using resistance heating or high frequency heating to form a vapor deposition film. Processing. The getter usually has Ba or the like as a main component, and due to the adsorption action of the deposited film, for example, 1 × 10
^-5 or 1 × 10 ^-7 Torr vacuum level is maintained.

Next, a configuration example of a drive circuit for performing television display based on a television signal of the NTSC method on a display panel constructed by using an electron source having a simple matrix arrangement will be described with reference to FIG. . In FIG. 9, 10
Reference numeral 1 is an image display panel, 102 is a scanning circuit, 103 is a control circuit, and 104 is a shift register. Reference numeral 105 is a line memory, 106 is a synchronizing signal separation circuit, 107 is a modulation signal generator, and Vx and Va are DC voltage sources.

The display panel 101 is connected to an external electric circuit via the terminals Dox1 to Doxm, the terminals Doy1 to Doyn, and the high voltage terminal Hv. Terminal Do
x1 to Doxm are for sequentially driving the electron sources provided in the display panel, that is, the surface conduction electron-emitting device groups matrix-wired in a matrix of M rows and N columns row by row (N elements). A scanning signal is applied.

A modulation signal for controlling the output electron beam of each element of the surface conduction electron-emitting devices of one row selected by the scanning signal is applied to the terminals Doy1 to Doyn. From the DC voltage source Va to the high voltage terminal Hv,
For example, a DC voltage of 10 K [V] is supplied, which is an accelerating voltage for imparting sufficient energy to excite the phosphor to the electron beam emitted from the surface conduction electron-emitting device.

The scanning circuit 102 will be described. The circuit is provided with M switching elements inside (schematically shown by S1 to Sm in the figure). Each switching element selects either the output voltage of the DC voltage source Vx or 0 [V] (ground level),
The terminals Dox1 to Doxm of the display panel 101 are electrically connected. Each of the switching elements S1 to Sm operates based on the control signal Tscan output from the control circuit 103, and can be configured by combining switching elements such as FETs.

In the case of the present embodiment, the DC voltage source Vx is an electron emission threshold value which is a drive voltage applied to an element which is not scanned based on the characteristics (electron emission threshold voltage) of the surface conduction electron emission element. It is set to output a constant voltage that is less than or equal to the voltage.

The control circuit 103 has a function of matching the operation of each unit so that an appropriate display is performed based on an image signal input from the outside. The control circuit 103, based on the synchronization signal Tsync sent from the synchronization signal separation circuit 106, outputs Tscan, Tsft, and Tm to each unit.
Each ry control signal is generated.

The sync signal separation circuit 106 is a circuit for separating a sync signal component and a luminance signal component from an externally input NTSC television signal, and uses a general frequency separation (filter) circuit or the like. Can be configured. The sync signal separated by the sync signal separation circuit 106 is composed of a vertical sync signal and a horizontal sync signal, but is shown here as a Tsync signal for convenience of explanation. The luminance signal component of the image separated from the television signal is represented as a DATA signal for convenience. The DATA signal is input to the shift register 104.

The shift register 104 performs serial / parallel conversion of the DATA signal serially input in time series for each line of the image, and is based on the control signal Tsft sent from the control circuit 103. The control signal Tsft can be said to be the shift clock of the shift register 104. The serial / parallel converted image data for one line (corresponding to drive data for N electron emission elements) is output from the shift register 104 as N parallel signals Id1 to Idn.

The line memory 105 is a storage device for storing data for one line of the image only for a required time, and stores the contents of Id1 to Idn in accordance with the control signal Tmry sent from the control circuit 103. The stored contents are output as I'd1 to I'dn,
It is input to the modulation signal generator 107.

The modulation signal generator 107 outputs the image data I ′.
a signal source for appropriately driving-modulating each of the surface conduction electron-emitting devices according to each of d1 to I′dn,
The output signal is applied to the surface conduction electron-emitting device in the display panel 101 through the terminals Doy1 to Doyn. This electron-emitting device has the following basic characteristics with respect to the emission current Ie. That is, the electron emission has a clear threshold voltage Vth, and the electron emission occurs only when a voltage higher than Vth is applied. For a voltage equal to or higher than the electron emission threshold value, the emission current also changes according to the change in the voltage applied to the device. Therefore, when a pulsed voltage is applied to this element, for example, electron emission does not occur even if a voltage below the electron emission threshold is applied, but when a voltage above the electron emission threshold is applied, an electron beam is emitted. Is output. At that time, the intensity of the output electron beam can be controlled by changing the pulse peak value Vm. Further, it is possible to control the total amount of charges of the electron beam output by changing the pulse width Pw. Therefore,
As a method of modulating the electron-emitting device according to an input signal, a voltage modulation method, a pulse width modulation method or the like can be adopted. When performing the voltage modulation method, the modulation signal generator 107
As such, a circuit of a voltage modulation method that generates a voltage pulse of a fixed length and appropriately modulates the peak value of the pulse according to the input data can be used.

In carrying out the pulse width modulation method, the modulation signal generator 107 generates a voltage pulse having a constant peak value and modulates the width of the voltage pulse appropriately according to the input data. A modulation method circuit can be used.

The shift register 104 and the line memory 10
As for 5, either a digital signal type or an analog signal type can be adopted. This is because the serial / parallel conversion and storage of the image signal may be performed at a predetermined speed.

When the digital signal type is used, it is necessary to convert the output signal DATA of the synchronizing signal separation circuit 106 into a digital signal, which may be provided with an A / D converter at the output portion of 106. In connection with this, the line memory 10
Depending on whether the output signal of 5 is a digital signal or an analog signal,
The circuit used for the modulation signal generator 107 is slightly different. That is, in the case of the voltage modulation method using a digital signal, for example, a D / A conversion circuit is used for the modulation signal generator 107, and an amplification circuit or the like is added if necessary. In the case of the pulse width modulation method, the modulation signal generator 107 includes, for example, a high-speed oscillator and a counter that counts the number of waves output from the oscillator, and a comparator that compares the output value of the counter with the output value of the memory. A circuit that combines (comparators) is used. If necessary, an amplifier for voltage-amplifying the pulse-width-modulated modulation signal output from the comparator to the drive voltage of the surface conduction electron-emitting device can be added.

In the case of the voltage modulation method using an analog signal,
As the modulation signal generator 107, for example, an amplifier circuit using an operational amplifier or the like can be adopted, and a level shift circuit or the like can be added if necessary. In the case of the pulse width modulation method, for example, a voltage controlled oscillation circuit (VCO) can be adopted, and an amplifier for amplifying the voltage up to the drive voltage of the surface conduction electron-emitting device can be added if necessary.

In the image display device of the present invention having such a structure, each electron-emitting device has a terminal Do outside the container.
Electrons are emitted by applying a voltage via x1 to Doxm and Doy1 to Doyn. A high voltage is applied to the metal back 85 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 84 to emit light, and an image is formed.

The configuration of the image forming apparatus described here is an example, and various modifications can be made based on the technical idea of the present invention. As for the input signal, the NTSC method is mentioned, but the input signal is not limited to this, and PAL, SECA
In addition to the M method, a TV signal (for example, a high-definition TV including the MUSE method) method including more scanning lines than the M method can be adopted.

Next, a ladder type electron source and an image forming apparatus will be described with reference to FIGS. Figure 1
0 is a schematic diagram showing an example of a ladder-type electron source. In FIG. 10, 110 is an electron source substrate, and 111 is an electron-emitting device. Reference numeral 112 (Dx1 to Dx10) is a common wiring for connecting the electron-emitting device 111. A plurality of electron-emitting devices 111 are arranged in parallel in the X direction on the substrate 110 (this is called a device row). A plurality of such element rows are arranged to form an electron source. By applying a drive voltage between the common lines of each element row, each element row can be driven independently. That is, a voltage equal to or higher than the electron emission threshold value is applied to the element row where the electron beam is desired to be emitted, and a voltage equal to or lower than the electron emission threshold value is applied to the element row which does not emit the electron beam. Common wiring Dx between each element row
As for 2 to Dx9, for example, Dx2 and Dx3 can have the same wiring.

FIG. 11 is a schematic view showing an example of a panel structure in an image forming apparatus provided with a ladder-type electron source. 120 is a grid electrode, 121 is a hole for passing electrons, and 122 is Dox1, Dox2, ..., Dox.
m is an outer terminal of the container. Reference numeral 123 is an external terminal of the container made of G1, G2, ..., Gn connected to the grid electrode 120, and 110 is an electron source substrate in which common wiring between the element rows is the same wiring. In FIG. 11, FIG. 7 and FIG.
The same parts as those shown in 0 are designated by the same reference numerals as those shown in these figures. A major difference between the image forming apparatus shown here and the image forming apparatus having the simple matrix arrangement shown in FIG. 7 is whether or not the grid electrode 120 is provided between the electron source substrate 110 and the face plate 86.

In FIG. 11, a grid electrode 120 is provided between the substrate 110 and the face plate 86. The grid electrode 120 is for modulating the electron beam emitted from the surface conduction electron-emitting device,
In order to allow the electron beam to pass through the stripe-shaped electrodes provided orthogonal to the ladder-shaped element rows, one circular opening 121 is provided for each element. The shape and installation position of the grid are not limited to those shown in FIG. For example, a large number of passage openings may be provided in the form of a mesh as openings, and the grid may be provided around or near the surface conduction electron-emitting device.

The terminal 122 outside the container and the terminal 123 outside the grid container are electrically connected to a control circuit (not shown).

In the image forming apparatus of this example, the modulation signals for one image line are simultaneously applied to the grid electrode columns in synchronization with the sequential driving (scanning) of the element rows one column at a time. This makes it possible to control the irradiation of the phosphor with each electron beam and display the image line by line.

The image forming apparatus using the display panel shown in FIGS. 7 and 11 is an optical printer including a photosensitive drum or the like in addition to a display device for television broadcasting, a display device such as a television conference system or a computer. Can also be used as an image forming apparatus or the like.

[0072]

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

(Embodiment 1) FIG. 1 is a drawing that best represents the features of the present invention. A method of forming an element electrode according to a first embodiment of the present invention will be described with reference to FIG.

First, as shown in FIG. 1A, Au is formed on a cleaned substrate 1 of soda lime glass by a screen printing method using a plate having a pattern of element electrodes 2 and 3 (gap width of 20 micrometers). 6 after applying the paste
It was baked at 00 ° C. At this time, the edges of the device electrodes 2 and 3 may not be smooth, or the surfaces may be porous. The paste material is not limited to Au,
The same was true for Cu and Ag.

Next, as shown in FIG. 1B, a silane coupling agent is applied to this substrate by a dipping method,
The glass substrate 1 was baked at 200 ° C. to form the hydrophobic surface 21. The coating method of the silane coupling agent is not limited to the dipping method, but a spin coating method or the like can be used.

Then, using a dipping method for this substrate,
When the metal-containing solution is applied, it repels the glass substrate,
As shown in FIG. 1C, the solution 22 was applied only on the device electrodes 2 and 3. As a result of firing this substrate at 300 ° C., an electrode having a smooth edge and a non-porous surface could be formed. Here, the coating method of the metal-containing solution is not limited to the dipping method, and the spin coating method and the ink jet method also have similar effects.

An organic metal solution was applied by spin coating to the device electrode produced by this manufacturing method, and the conductive thin film 4 was formed by patterning by etching (FIG. 3B). Was small and good. The method for forming the conductive thin film 4 is not limited to this, and the vacuum deposition method, sputtering method, chemical vapor deposition method, dispersion coating method,
A dipping method, an inkjet method, etc. can also be used.

Example 2 An Au paste was applied to a substrate 1 made of cleaned soda-lime glass by offset printing using a plate having an element electrode pattern (gap width of 20 micrometers), and then baked at 600 ° C. However, the same problem as in Example 1 may occur. Therefore, when the metal-containing solution was applied only on the device electrode and fired by the same method as in Example 1, the same effect was obtained.

(Example 3) Similarly to Example 1, a washed blue plate substrate was subjected to screen printing to form electrodes, which was subjected to a hydrophobic treatment, and a metal-containing solution was applied by an ink jet spraying device. The solution was applied only on the device electrodes by being repelled on the substrate. This was fired to obtain an electrode with a smooth edge and a non-porous surface.

An organic metal solution was applied to the device electrode by this manufacturing method by spin coating and patterned by etching to form a conductive thin film 4 (FIG. 3 (b)). Was small and good. The method for forming the conductive thin film 4 is not limited to this, and the vacuum deposition method, sputtering method, chemical vapor deposition method, dispersion coating method,
A dipping method, an inkjet method, etc. can also be used.

Example 4 As Example 4, Examples 1 to 1
A display panel of a display using the surface conduction electron-emitting devices arranged in MTX (matrix) using the device electrodes according to the manufacturing method of 3 was manufactured. FIG. 4 shows a part of a rear panel of a display using the surface conduction electron-emitting device.

That is, first, on the glass substrate on which the element electrodes 2 and 3 and the conductive thin film were formed by the method of Examples 1 to 3,
A row direction wiring 6, an interlayer insulating film 7 and a column direction wiring 8 were sequentially formed by a screen printing method to manufacture a rear panel. Wirings 6 and 8 are thinly formed by screen printing, and then
It can also be formed thick by plating.

After that, the rear panel on which the wiring and the electron emitting portion are formed and the face panel provided with the phosphor are opposed to each other, and sealed with a frit glass at a temperature of about 400 ° C. or more through a supporting frame to form a vacuum. The container part was formed.
After the sealing step, the above-mentioned mounting and forming were performed to form an electron emitting portion. When an image was displayed by passing an electric current in parallel with the film surface of the electron emitting portion, uniform brightness was obtained.

In this embodiment, the element electrodes are first formed, but the wiring and the insulating layer are formed first by the printing method,
After that, the device electrode may be formed by the method of the first embodiment.

By manufacturing a display using the surface conduction electron-emitting device by the above manufacturing method, the cost is lower than the thin film process and the manufacturing yield is greatly improved.

[0086]

As described above, by using the manufacturing method of the present invention, a device electrode having a smooth gap portion and a non-porous surface can be formed, and variations in device characteristics are reduced. Further, in the display using the surface conduction electron-emitting device using this device electrode manufacturing method, since the printing method can be used, the cost can be reduced in a larger area compared to the case where the photolithography technique is used, and This has the effect of improving the manufacturing yield.

[Brief description of drawings]

FIG. 1 is a perspective view showing a manufacturing method according to an embodiment of the present invention.

FIG. 2 is a schematic plan view and a cross-sectional view showing a configuration of a planar surface conduction electron-emitting device according to an embodiment of the present invention.

FIG. 3 is a schematic view showing a method of manufacturing a surface conduction electron-emitting device according to an embodiment of the present invention.

FIG. 4 is a diagram showing a part of a matrix arrangement type electron source substrate of the present invention.

FIG. 5 is a schematic diagram showing an example of a voltage waveform in an energization forming process that can be adopted when manufacturing the surface conduction electron-emitting device of the present invention.

FIG. 6 is a schematic view showing an example of a matrix arrangement type electron source substrate to which the present invention can be applied.

FIG. 7 is a schematic diagram showing an example of a display panel of an image forming apparatus to which the present invention can be applied.

8 is a schematic diagram showing an example of a fluorescent film applicable to the apparatus of FIG.

9 is a block diagram showing an example of a drive circuit for performing display on the display panel of FIG. 7 in accordance with an NTSC television signal.

FIG. 10 is a schematic view showing an example of a ladder arrangement type electron source substrate to which the present invention can be applied.

FIG. 11 is a schematic view showing an example of a display panel of an image forming apparatus to which the present invention can be applied.

FIG. 12 is a diagram showing a conventional example of a surface conduction electron-emitting device.

[Explanation of symbols]

1: substrate, 2: 3: element electrode, 4: conductive thin film, 5: electron emission part, 6: row-direction wiring, 7: interlayer insulating film, 8: column-direction wiring, 21: hydrophobic surface, 22: metal-containing Solution, 71: Electron source substrate, 72: X-direction wiring, 73: Y-direction wiring, 7
4: surface conduction electron-emitting device, 75: connection, 81: rear plate, 82: support frame, 83: glass substrate, 84: fluorescent film, 85: metal back, 86: face plate,
87: high-voltage terminal, 88: envelope, 91: black member, 9
2: phosphor, 101: display panel, 102: scanning circuit,
103: control circuit, 104: shift register, 105:
Line memory, 106: synchronization signal separation circuit, 107: modulation signal generator, V _x , V _a : DC voltage source, 110: electron source substrate, 111: electron emission element, 112: Dx1 to Dx.
Reference numeral 10 is a common wiring for wiring the electron-emitting device, 12
0: Grid electrode, 121: Open holes for passing electrons, 122: Dox1, Dox2, ... Dox
m outer terminal of the container, 123: G1 and G2 connected to the grid electrode 120.

Claims (6)

(57) [Claims] 1. A method for manufacturing a surface conduction electron-emitting device, which comprises at least a pair of device electrodes on an insulating substrate, and a thin film provided between the device electrodes and including an electron-emitting portion, comprising: step of forming the electrode, on the insulating substrate, by a printing method, tables in the material of the device electrodes
A step of forming an element electrode pattern having a porous surface ; a step of subjecting the insulating substrate having the element electrode pattern to a hydrophobic treatment; and, after the hydrophobic treatment, a metal-containing solution is applied to the element electrode pattern.
A method of manufacturing an electron-emitting device, which comprises: Wherein the coating of the metal-containing solution, a manufacturing method of claim 1 Koho <br/> detecting element electrodeposition, wherein the performing by dipping. Wherein the coating of the metal-containing solution, child electrodeposition according to claim 1, characterized in that an ink jet method
Method for producing a release detecting element. 4. A method of manufacturing an electron source substrate, characterized in that an electron source substrate having a simple matrix arrangement is manufactured by using the electron emitting device manufactured by the method according to any one of claims 1 to 3. 5. A method of manufacturing an electron source substrate, which comprises manufacturing an electron source substrate in a ladder arrangement using the electron-emitting device manufactured by the method according to any one of claims 1 to 3. 6. A method according to any one of claims 1 to 3.
An image forming apparatus is manufactured by using the electron-emitting device described above.