JPH0845415A - Electron emission element and its manufacture electron source using this element and its manufacture and image forming method using this source - Google Patents

Abstract

PURPOSE:To provide a surface conductive electron emission element showing a uniform electron emission characteristic. CONSTITUTION:After element electrodes 2 and 2' are formed on an insulating substrate 1, the first conductive thin film 3 is first formed and made to have a crack via treatment under the supply of electric power. Furthermore, the second conductive thin film 4 is formed on it and again subjected to treatment under the supply of electric power to form a crack 5.

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 in which a large number of such devices are arranged, and an image forming apparatus such as a display device and an exposure device configured by using the electron source. Furthermore, the present invention relates to a method for manufacturing the surface conduction electron-emitting device and the electron source.

[0002]

2. Description of the Related Art A surface conduction electron-emitting device utilizes a phenomenon in which electron emission occurs when a current is passed through a conductive thin film formed on an insulating substrate in parallel with the film surface.

As a typical example of the structure of the surface conduction electron-emitting device, a conductive thin film such as a metal oxide which connects between a pair of device electrodes provided on an insulating substrate is referred to as forming in advance. The thing which formed the electron emission part by the electricity supply process is mentioned. Forming is usually performed by applying a voltage to both ends of the conductive thin film, and the structure is changed by locally destroying, deforming or degrading the conductive thin film, and the electron emitting portion in an electrically high resistance state is formed. Is a process for forming. The electron emission is performed from the vicinity of the crack generated in the electron emitting portion by applying a voltage to the conductive thin film in which the electron emitting portion is formed and flowing a current.

Since the surface conduction electron-emitting device has a simple structure and is easy to manufacture, it has an advantage that a large number of arrays can be formed over a large area. Therefore, various applications for utilizing this feature are being researched. For example, it can be used for an image forming apparatus such as a display device.

Conventionally, as an example in which a large number of surface conduction electron-emitting devices are formed in an array, surface conduction electron-emitting devices are arranged in parallel and both ends (both device electrodes) of each surface conduction electron-emitting device are wired. An electron source in which a large number of rows connected by (also called common wiring) are arranged (also called a ladder arrangement) is disclosed (Japanese Patent Laid-Open Nos. 1-33132 and 1-2837).
No. 49, No. 1-275552). Further, particularly in the case of a display device, a large number of surface conduction electron-emitting devices can be used as a self-luminous display device that can be a flat panel display device similar to a display device using liquid crystal and does not require a backlight. A display device has been proposed in which an arranged electron source is combined with a phosphor that emits visible light when irradiated with an electron beam from the electron source (US Pat. No. 5,066,506).
883).

In order to obtain a high-quality, high-definition image on a large screen in a display device using the surface-conduction type electron-emitting devices, the number of rows and columns of the surface-conduction type electron-emitting devices is several hundreds, respectively. It is necessary to arrange a large number of surface conduction electron-emitting devices, which is several thousand. Therefore, it is desired that the electric characteristics of each surface conduction electron-emitting device be uniform and easy to control.

[0007]

However, the surface conduction electron-emitting device has the following problems.

In the surface conduction electron-emitting device, electrons are emitted from the crack formed by the above-mentioned forming, and therefore the electron emission characteristic depends on the width of the crack and the like. Therefore, ideally, it is desirable that uniform and narrow cracks are formed. However, the actual conductive thin film for forming the electron-emitting portion has slight variations in film thickness, contact resistance between the device electrode and the thin film, etc. between the individual thin films, and even if the same voltage is applied, it is different from the crack formed. Will occur.

Further, in an electron source having a large number of surface-conduction type electron-emitting devices arranged, if each surface-conduction type electron-emitting device has uneven emission characteristics, uneven brightness occurs when a display device is constructed. Will end up.

Therefore, it is necessary to electrically control the forming process according to each thin film, or to form a thin film so that the film thickness and contact resistance of the thin film become uniform. The method is also undesirable because it may increase the production cost.

An object of the present invention is to solve the above problems and to provide a surface conduction electron-emitting device exhibiting the same electron emission characteristics, and a thin film may have some variations in film thickness and contact resistance. Even so, it is an object of the present invention to provide a method for manufacturing a surface conduction electron-emitting device that exhibits equivalent electron emission characteristics.

Specifically, it is an object of the present invention to provide a method for forming an electron emitting portion which emits an equivalent electron beam in a thin film in a manufacturing process of a surface conduction electron emitting device.

A further object of the present invention is to construct an electron source in which a large number of surface conduction electron-emitting devices having the above-mentioned uniform electron emission characteristics are arranged, and the electron emission does not vary among the devices. To provide a source and a manufacturing method thereof.

A further object of the present invention is to provide an image forming apparatus such as a display device using the above electron source.

[0015]

The inventions of claims 1 to 5 provide a surface conduction electron-emitting device which solves the above-mentioned problems, in which a conductive thin film is composed of at least two layers, and a device electrode. The present invention is characterized in that a lower layer thin film having a crack in a gap, an upper layer thin film is formed on the lower layer crack, and an upper layer thin film crack is formed inside the lower layer thin film crack.

The invention of claims 6 to 8 is a method for manufacturing the above-mentioned surface conduction electron-emitting device, wherein in the step of forming the electron-emitting portion, at least a first conductive thin film is formed and a voltage is applied to the thin film. It has a step of applying a crack to form a crack, and a step of forming a second conductive thin film on the cracked thin film at least once and applying a voltage again to form a crack. And

Further, the invention of claims 9 to 10 is an electron source using a large number of the above-mentioned surface conduction electron-emitting devices, and the invention of claim 13 is a method of manufacturing one of the electron sources, which is a matrix wiring. When one is the X-direction wiring and the other is the Y-direction wiring, the Y-direction wiring is commonly connected and connected to one pole of the voltage applying means, and the X-direction wiring is sequentially connected to the other pole of the voltage applying means. Then, when a voltage is applied to the conductive thin film for each element connected to the same X-direction wiring and a voltage is applied to the second and subsequent thin films, the voltage is applied to the thin film of the previous layer. It is characterized in that the X-direction wiring end on the opposite side is connected to the voltage applying means.

The fourteenth and fifteenth aspects are inventions relating to an image forming apparatus using the electron source.

As described above, the present invention relates to a novel surface conduction electron-emitting device, an electron source using a plurality of surface conduction electron-emitting devices, an image forming apparatus using the same, and manufacturing methods thereof. The configuration and operation of each invention will be further described below.

Surface-conduction type electron-emitting devices are classified into a flat type and a vertical type, and any surface-conduction type electron-emitting device can be constructed in the present invention. First, the basic structure of the planar surface conduction electron-emitting device will be described.

1 (a) and 1 (b) are configuration diagrams showing the basic configuration of a planar surface conduction electron-emitting device.

In FIG. 1, 1 is a substrate, 2 and 2'are device electrodes, 3 is a first conductive thin film, 4 is a second conductive thin film,
5 is a crack.

The substrate 1 is, for example, quartz glass or Na.
Examples thereof include glass having a reduced content of impurities such as blue glass, soda lime glass, a laminated body obtained by laminating SiO ₂ on soda lime glass by a sputtering method, and ceramics such as alumina.

As a material for the device electrodes 2 and 2'which face each other, a general conductor material is used, for example, Ni, Cr, A.
Metals or alloys such as u, Mo, W, Pt, Ti, Al, Cu, Pd and Pd, Ag, Au, RuO ₂ , Pd-
It is appropriately selected from a printed conductor composed of a metal such as 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 spacing L, the element electrode length W, the shape of the conductive thin film 34, etc. are designed according to the applied form.

The device electrode spacing L is preferably several hundred Å to several hundred μm, more preferably the device electrodes 2, 2 '.
Depending on the voltage applied between and the electric field strength that can emit electrons,
It is several μm to several tens of μm.

The device electrode length W is preferably several μm to several hundreds μm, and the device electrode thickness d is several hundred Å to several μm in consideration of the resistance value of the electrodes and electron emission characteristics.

The conductive thin films 3 and 4 are particularly preferably a fine particle film composed of fine particles in order to obtain good electron emission characteristics. It is appropriately selected depending on the coverage, the resistance value between the element electrodes 2 and 2 ′, the forming condition described later, and the like.
The thickness of the electroconductive thin films 3 and 4 is preferably several Å to several thousand Å, particularly preferably 10 Å to 500 in total.
Å, and the resistance value is a sheet resistance value of 10 ³ to 10 ⁷ Ω / □.

PdO, Pd or a mixture thereof is preferably used as a material for forming the conductive thin films 3 and 4, but in addition to this, a conductive film such as an Au vapor deposition film or a SnO ₂ sputtered film is preferably used. Can be used.

The fine particle film is a film in which a plurality of fine particles are aggregated, and its fine structure is not only in a state where the fine particles are dispersed and arranged but also in a state where the fine particles are adjacent to each other or overlap each other (island shape). Including). In the case of a fine particle film, the particle diameter of the fine particles is preferably several Å to several thousand Å, particularly preferably 10 Å to 200 Å.

Next, the basic structure of the vertical surface conduction electron-emitting device will be described.

FIG. 1C is a structural view showing the basic structure of a vertical surface conduction electron-emitting device, in which 6 is a step forming member, and is otherwise the same as in FIGS. 1A and 1B. The reference numerals indicate the same members.

The substrate 1, the device electrodes 2, 2 ', and the conductive thin films 3, 4 are made of the same material as that of the above-mentioned planar surface conduction electron-emitting device.

The step forming member 6 is made of an insulating material such as SiO _{2 provided} by, for example, a vacuum vapor deposition method, a printing method, a sputtering method or the like. The film thickness of the step forming member 6 corresponds to the element electrode spacing L (see FIG. 1B) of the above-mentioned planar surface conduction electron-emitting device. It is set by the voltage applied between the electrodes 2 and 2'and the electric field strength capable of emitting electrons, but is preferably several hundred Å to several tens of μm, particularly preferably several hundred Å
~ Several μm.

The following description is based on the above-mentioned planar surface conduction electron-emitting device and vertical surface conduction electron-emitting device.
A plane type will be described as an example, but a vertical type surface conduction electron-emitting device may be used instead of the plane type surface conduction electron-emitting device.

Various methods are conceivable as a method of manufacturing the surface conduction electron-emitting device, one example of which will be described with reference to FIG. In FIG. 2, the same reference numerals as those in FIG. 1 denote the same members.

(A) After thoroughly cleaning the substrate 1 with a detergent, pure water and an organic solvent, after depositing a device electrode material by a vacuum deposition method, a sputtering method or the like, a photolithography technique is applied to the surface of the substrate 1. Element electrodes 2 and 2'are formed (FIG. 2A).

(B) By coating an organic metal solution on the substrate 1 provided with the element electrodes 2 and 2'and leaving it to stand, the element electrodes 2 and 2'are connected to each other to form an organic metal thin film. . The organic metal solution is a solution of an organic compound whose main element is the metal of the above-mentioned conductive thin films 3 and 4. Then, the organic metal thin film is heated and baked to form the first conductive thin film 3 patterned by lift-off, etching, etc. (FIG. 2B). In addition, although the description has been given here by using the coating method of the organic metal solution, the present invention is not limited to this, and for example, a vacuum deposition method, a sputtering method, a chemical vapor deposition method, a dispersion coating method, a dipping method, a spinner method, or the like can be used. A film can also be formed.

(C) Subsequently, the first conductive thin film 3 is subjected to an energization process called forming. Element electrodes 2, 2 '
In the meantime, when electricity is applied from a power source (not shown), the first crack 22 is formed in the conductive thin film 3.

FIG. 3 shows an example of the voltage waveform of forming at this time.

The voltage waveform is particularly preferably a pulse waveform,
There are a case where a voltage pulse whose pulse peak value is a constant voltage is continuously applied (FIG. 3A), and a case where a voltage pulse is applied while increasing the pulse peak value (FIG. 3B).

First, the case where the pulse peak value is a constant voltage will be described with reference to FIG.

In FIG. 3A, T ₁ and T ₂ are the pulse width and pulse interval of the voltage waveform, for example, T ₁ is 1 μm.
sec to 10 msec, T ₂ 10 μsec to 100 m
csec, the peak value (peak voltage during forming) is appropriately selected according to the form of the surface conduction electron-emitting device described above, and is applied for several seconds to several tens of minutes in a vacuum atmosphere with an appropriate degree of vacuum. The voltage waveform to be applied is not limited to the illustrated triangular wave, and a desired waveform such as a rectangular wave can be used.

(D) Furthermore, the first conductive thin film 3 and the first
The step (B) is repeated on the crack 22 to form the second conductive thin film 4 (FIG. 2D), and the step (C) is performed to form the second crack 23.

The basic characteristics of the surface conduction electron-emitting device thus obtained will be described below.

FIG. 4 is a schematic block diagram showing an example of a measurement / evaluation system for measuring the electron emission characteristics of the surface conduction electron-emitting device. First, this measurement / evaluation system will be described.

4, the same reference numerals as those in FIG. 1 indicate the same members. Further, 41 is a power source for applying a device voltage V _f to the device, 40 is a conductive thin film 3 between the device electrodes 2 and 2 ′.
An ammeter for measuring a device current I _f flowing through 4, 44
Is an anode electrode for capturing the emission current I _e , 43 is a high voltage power source for applying a voltage to the anode electrode 44, 4
2 is an ammeter for measuring the emission current I _e , 45 is a vacuum device, and 46 is an exhaust pump.

The SCE, the anode electrode 44, etc. are arranged in a vacuum device 45, and this vacuum device 45 is equipped with necessary equipment such as a vacuum gauge (not shown), and S under a desired vacuum.
The CE can be measured and evaluated.

The exhaust pump 46 is composed of a normal high vacuum system such as a turbo pump and a rotary pump, and an ultra high vacuum system including an ion pump. The entire vacuum device 45 and the substrate 1 of the SCE can be heated up to about 200 ° C. by a heater.

The basic characteristics of the surface conduction electron-emitting device described below are that the voltage of the anode electrode 44 of the above measurement and evaluation system is 1 kV to 10 kV, and the distance H between the anode electrode 44 and the surface conduction electron-emitting device is 2 to 8 mm. As usually measured.

First, the emission current I _e and the device current I _f ,
A typical example of the relationship with the device voltage V _f is shown in FIG. still,
In FIG. 5, the emission current I _e is markedly smaller than the device current I _f, and therefore is shown in arbitrary units.

As is apparent from FIG. 5, the surface conduction electron-emitting device has the following three characteristic characteristics with respect to the emission current I _e .

First of all, in the surface conduction electron-emitting device, when a device voltage V _f higher than a certain voltage (called threshold voltage: V _{th in} FIG. 5) is applied, the emission current I _e rapidly increases. ,
On the other hand, at the threshold voltage V _th or less, the emission current I _e is hardly detected. That is, it is a non-linear element having a clear threshold voltage V _th with respect to the emission current I _e .

Secondly, since the emission current I _e has a characteristic (called MI characteristic) that the emission current I _e monotonically increases with respect to the element voltage V _f , the emission current I _e can be controlled by the element voltage V _f .

Thirdly, the emitted charges trapped in the anode electrode 44 (see FIG. 4) depend on the time for applying the device voltage V _f . That is, the amount of charge captured by the anode electrode 44 can be controlled by the time for which the device voltage V _f is applied.

The emission current I _e is MI with respect to the device voltage V _f .
At the same time having a characteristic, it may have a MI characteristic with respect to the device current I _f also the device voltage V _f. An example of the characteristics of such a surface conduction electron-emitting device is the characteristics shown by the solid line in FIG. On the other hand, as indicated by the broken line in FIG. 5, the device current _If is different from the device voltage _Vf in the voltage controlled negative resistance characteristic (VCN).
R characteristics). Which characteristic is exhibited depends on the manufacturing method of the surface conduction electron-emitting device and the measurement conditions at the time of measurement. However, the element current I _f is equal to the element voltage V _f
On the other hand, even in the surface conduction electron-emitting device having the VCNR characteristic, the emission current I _e has the MI characteristic with respect to the device voltage V _f .

When observing the morphology of cracks in the conventional surface conduction electron-emitting device with a scanning electron microscope, the cracks are connected from the narrow portion to the wide portion while intersecting each other. It is considered that the local electron emission amount and current amount change variously depending on the width of the crack.

In the surface conduction electron-emitting device of the present invention, the current is concentrated at the location where the crack of the first conductive thin film is wide because the resistance becomes large during the energization treatment of the second conductive thin film. do not do. Rather, the electric current concentrates on a small crack in the first layer and the crack starts to propagate from here. Therefore, it is considered that when the formation of the second crack is completed, a uniform narrow crack is formed, the portion contributing to electron emission is increased, and preferable characteristics are obtained.

Further, in the surface conduction electron-emitting device of the present invention, the thickness of the second conductive thin film is made smaller than that of the first conductive thin film, so that the joules generated when the second crack is formed. The heat is reduced, the thermal damage to the first conductive thin film is reduced, and the cracks initially formed by the thermal damage are prevented from spreading.

Depending on the use of the surface conduction electron-emitting device, the patterning of the second conductive thin film can be omitted. In this case, since the thickness of the second conductive thin film is thin and the electric resistance is large, the current concentrates on a portion where the first conductive thin film exists, and the leak current flowing to other portions does not become so large.

Next, the arrangement of the surface conduction electron-emitting devices in the electron source of the present invention will be described.

As a method of arranging the surface conduction electron-emitting devices in the electron source of the present invention, in addition to the ladder arrangement as described in the section of the prior art, n Ys on m X-direction wirings are arranged. There is an arrangement method in which directional wirings are provided via an interlayer insulating layer and an X-direction wiring and a Y-direction wiring are connected to a pair of device electrodes of a surface conduction electron-emitting device, respectively. This is hereinafter referred to as a simple matrix arrangement. First, this simple matrix arrangement will be described in detail.

According to the basic characteristics of the surface conduction electron-emitting device described above, the emitted electrons in the surface conduction electron-emitting device arranged in the simple matrix are between the opposing device electrodes at a voltage exceeding the threshold voltage. It can be controlled by the peak value and pulse width of the applied pulsed voltage. On the other hand, almost no electrons are emitted below the threshold voltage. Therefore, even when a large number of surface conduction electron-emitting devices are arranged, if the pulsed voltage is appropriately applied to each device, the surface conduction electron-emitting device is selected according to the input signal and the electron emission amount thereof is selected. Can be controlled, and individual surface conduction electron-emitting devices can be selected and driven independently by simple matrix wiring.

The simple matrix arrangement is based on such a principle, and the structure of the electron source having the simple matrix arrangement, which is an example of the electron source of the present invention, will be further described with reference to FIG.

In FIG. 6, the substrate 1 is a glass plate or the like as already described, and the number and shape of the surface conduction electron-emitting devices 104 arranged on the substrate 1 are set appropriately according to the application. is there.

The m wirings in the X direction 102 have external terminals D _x1 , D _x2 , ..., D _xm , respectively.
It is a conductive metal or the like formed by a vacuum deposition method, a printing method, a sputtering method, or the like. In addition, a large number of surface conduction electron-emitting devices 10
4 so that the voltage is supplied to the 4 substantially evenly, the material, the film thickness,
The wiring width is set.

The n Y-direction wirings 103 have external terminals D _y1 , D _y2 , ..., D _yn , respectively.
It is created in the same way as 02.

These m X-direction wirings 102 and n Y-wirings
An interlayer insulating layer (not shown) is provided between the directional wirings 103 and electrically separated to form a matrix wiring. In addition, both m and n are positive integers.

The interlayer insulating layer (not shown) is SiO ₂ or the like formed by a vacuum deposition method, a printing method, a sputtering method or the like, and has a desired shape on the entire surface or a part of the substrate 1 on which the X-direction wiring 102 is formed. In particular, the film thickness, material, and manufacturing method are appropriately set so as to withstand the potential difference at the intersection of the X-direction wiring 102 and the Y-direction wiring 103.

Furthermore, the opposing device electrodes (not shown) of the surface conduction electron-emitting device 104 are m number of X-direction wirings 102.
, N Y-direction wirings 103, a vacuum deposition method, a printing method,
Connection 1 made of a conductive metal or the like formed by a sputtering method or the like
05 are electrically connected.

Here, the m X-direction wirings 102, the n Y-direction wirings 103, the connecting wires 105, and the opposing element electrodes may have the same or partial constituent elements. Further, they may be different from each other, and are appropriately selected from the above-mentioned material of the element electrode and the like. Wirings to these element electrodes may be collectively referred to as element electrodes when the same material as the element electrodes is used. In addition, the surface conduction electron-emitting device 104
May be formed either on the substrate 1 or on an interlayer insulating layer (not shown).

Further, as will be described later in detail, a scanning signal is applied to the X-direction wiring 102 in order to scan the rows of the surface conduction electron-emitting devices 104 arranged in the X-direction according to an input signal. A scanning signal applying means (not shown) is electrically connected.

On the other hand, a modulation signal (not shown) is applied to the Y-direction wiring 103 in order to modulate each row of the surface conduction electron-emitting devices 104 arranged in the Y-direction according to an input signal. The signal generating means is electrically connected. Further, the drive voltage applied to each surface conduction electron-emitting device 104 is supplied as a difference voltage between the scanning signal and the modulation signal applied to the surface conduction electron-emitting device 104.

The feature of the method of manufacturing an electron source of the present invention is that in forming the electron source of the simple matrix arrangement described above,
The end of the X-direction wiring connected to the power supply is changed in the forming process of the first conductive thin film and the forming process of the second conductive thin film.

This will be specifically described with reference to FIG.

In FIG. 7, 72 is a pulse generator, the positive electrode of which is connected to one end of the X-direction wiring, and the negative electrode of which is the shunt resistor 7.
3 to the ground, and the Y-direction wiring 103 to the ground via the common electrode. Other Figure 6
The same reference numerals as indicate the same members.

As described in the manufacturing example of the surface conduction electron-emitting device, first, the first conductive thin film is formed, and then the forming process of the thin film is performed in the wiring state. Next, a second conductive thin film is formed, and a pulse generator 7 is provided at the X-direction wiring end on the side opposite to the first forming (that is, on the right-hand side).
2 is connected and forming is performed.

In an electron source in which a large number of surface conduction electron-emitting devices are arranged, when the Y-direction wiring is connected in common and the forming process is performed after the X-direction waste wire, the resistance of the X-direction wiring causes As the element is farther from the current supply end, the effective voltage of the element decreases. Therefore, a crack is formed from the element on the side closer to the current supply end, and as the voltage to be supplied is gradually increased, the crack formation progresses in order to the next element.

Since the element in which a crack is formed has a high resistance and no current flows, the current flowing into the X-direction wiring decreases when the crack formation progresses to some extent, and the voltage drop due to the wiring resistance becomes small. For this reason, the effective voltage applied to the element near the end opposite to the current supply end begins to rise rapidly, the supply power exceeds the threshold value for crack formation all at once, excess power is input, and the crack width widens. As a result, in the element on the side opposite to the current supply end, the amount of electron emission becomes small, the brightness becomes low, and there occurs a phenomenon that the brightness is different at both ends.

On the other hand, in the electron source of the present invention, although there is a difference in the amount of electron emission at the both ends at the stage of forming the first crack, a second conductive thin film is further formed, The energization process is performed by replacing the current supply end with the opposite side. At this time, in the element near the second current supply end, the first crack width is wide and the resistance is large, and in the distant element, the first crack width is narrow and the resistance is small. Therefore, it is considered that the tendency of excessive power supply to the element far from the current supply end is alleviated with the progress of crack formation, and as a result, the uniformity is improved.

Next, an example of the image forming apparatus of the present invention using the electron source of the present invention having the above simple matrix arrangement will be described with reference to FIGS. Note that FIG. 8 is a basic configuration diagram of the display panel 201, FIG. 9 is a diagram showing the fluorescent film 114, and FIG. 10 is the display panel 201 of FIG.
It is a block diagram showing an example of a drive circuit for performing a television display according to a television signal of a TSC system.

In FIG. 8, 1 is a substrate of an electron source in which the surface conduction electron-emitting devices are arranged as described above, 111 is a rear plate to which the substrate 1 is fixed, and 116 is a glass substrate 1.
A face plate having a fluorescent film 114, a metal back 115 and the like formed on the inner surface of 13 and a support frame 112. Frit glass or the like is applied to the rear plate 111, the support frame 112, and the face plate 116, and the atmosphere or nitrogen is used. Then, the envelope 118 is configured by sealing by baking at 400 to 500 ° C. for 10 minutes or more.

In FIG. 8, reference numerals 102 and 103 denote X-direction wiring and Y-direction wiring connected to the pair of device electrodes 2 and 2'of the surface conduction electron-emitting device 104, respectively.
_{It has x1 to} D _xm and D _{y1 to} D _yn .

The envelope 118 is composed of the face plate 116, the support frame 112 and the rear plate 111 as described above. However, the rear plate 111 is provided mainly for the purpose of reinforcing the strength of the substrate 1, and when the substrate 1 itself has sufficient strength, the separate rear plate 111 is not necessary, and the rear plate 111 is directly supported on the substrate 1. 112 is sealed,
The envelope 118 may be composed of the face plate 116, the support frame 112, and the substrate 1. Further, by further installing a support body (not shown) called a spacer between the face plate 116 and the rear plate 111, it is possible to form the envelope 118 having sufficient strength against atmospheric pressure.

In the case of monochrome, the fluorescent film 114 is composed of only the phosphor 122, but in the case of the color fluorescent film 114, depending on the arrangement of the phosphors 122, a black stripe (FIG. 9A) or a black matrix (FIG. 9) is used. 9
(B)) Black conductive material 121 and phosphor 122, etc.
Composed of and. The purpose of providing the black stripes and the black matrix is to make the color mixture, etc., inconspicuous by making the coating portions between the phosphors 122 of the three primary colors necessary for color display black, and to reflect external light on the phosphor film 114. This is to suppress the decrease in contrast due to. As the material of the black conductive material 121, not only a commonly used material containing graphite as a main component, but also another material may be used as long as it is conductive and has little light transmission and reflection. it can.

As a method for applying the phosphor 122 to the glass substrate 113, a precipitation method or a printing method is used regardless of monochrome or color.

Further, as shown in FIG.
A metal back 115 is usually provided on the inner surface side of 4.
The purpose of the metal back 115 is to improve the brightness by specularly reflecting the light to the inner surface side of the light emission of the phosphor 122 (see FIG. 9) to the glass substrate 113 side, and to apply an electron beam acceleration voltage. Acting as an electrode,
For example, protection of the phosphor 122 from damage due to collision of negative ions generated in the envelope 118. Metal back 1
15 can be manufactured by performing smoothing processing (usually called filming) on the inner surface of the fluorescent film 114 after manufacturing the fluorescent film 114, and then depositing Al by vacuum evaporation or the like.

The face plate 116 may be provided with a transparent electrode (not shown) on the outer surface side of the fluorescent film 114 in order to further enhance the conductivity of the fluorescent film 114.

At the time of performing the above-mentioned sealing, in the case of a color, the phosphors 122 of the respective colors have to correspond to the surface conduction electron-emitting devices 104, so that it is necessary to perform sufficient alignment.

The inside of the envelope 118 is sealed through a vacuum degree of about 10 ⁻⁷ torr through an exhaust pipe (not shown).
Also, the getter process may be performed immediately before or after the envelope 118 is sealed. This is the envelope 1
It is a process of heating a getter (not shown) arranged at a predetermined position in 18 to form a vapor deposition film. Getter is usually B
The main component is a and the like, and is for maintaining a vacuum degree of, for example, 1 × 10 ⁻⁵ to 1 × 10 ⁻⁷ torr by the adsorption action of the vapor deposition film.

The above-mentioned display panel 201 is shown in FIG.
It can be driven by a driving circuit as shown in FIG.
In FIG. 10, 201 is a display panel, 202 is a scanning circuit, 203 is a control circuit, 204 is a shift register,
205 is a line memory, 206 is a sync signal separation circuit, 2
Reference numeral 07 is a modulation signal generator, and V _x and V _a are DC voltage sources.

As shown in FIG. 10, the display panel 20
1 is connected to an external electric circuit via the external terminals D _{x1 to} D _xm , the external terminals D _{y1 to} D _yn, and the high voltage terminal Hv.
Of these, the external terminals D _{x1 to} D _xm are connected to the display panel 201.
A scanning signal for sequentially driving the surface conduction electron-emitting devices provided therein, that is, the group of surface conduction electron-emitting devices arranged in a matrix of m rows and n columns in one row (n elements at a time). Is applied.

On the other hand, a modulation signal for controlling the output electron beam of each surface conduction electron-emitting device of one row selected by the scanning signal is applied to the external terminals D _{y1 to} D _yn . Further, a DC voltage of, for example, 10 kV is supplied from the DC voltage source V _a to the high voltage terminal Hv. This is an accelerating voltage for giving enough energy to excite the phosphor to the electron beam output from the surface conduction electron-emitting device.

The scanning circuit 202 is provided with m switching elements (schematically shown by S _{1 to} S _m in FIG. 10) inside, and each switching element S _{1 to} S _m is a DC voltage power supply V _x. Output voltage or 0 V (ground level) is selected and electrically connected to the external terminals D _{x1 to} D _{xm of} the display panel 201. Each of the switching elements S _{1 to} S _m operates based on the control signal T _scan output from the control circuit 203, and in practice, is easily configured by combining elements having a switching function such as FETs. It is possible.

The DC voltage source V _x in this example is driven by a drive voltage applied to an unscanned surface conduction electron-emitting device based on the characteristics (threshold voltage) of the surface conduction electron-emitting device. It is set to output a constant voltage that is less than or equal to the threshold voltage.

The control circuit 203 has a function of matching the operation of each part so that an appropriate display is performed based on an image signal input from the outside. Based on a synchronization signal T _sync sent from a synchronization signal separation circuit 206 described below, control signals T _scan , T _sft, and T _mry are generated for each unit.

The sync signal separation circuit 206 is a circuit for separating a sync signal component and a luminance signal component from an NTSC television signal input from the outside, and as is well known, a frequency separation (filter). If you use a circuit,
It can be easily constructed. Sync signal separation circuit 206
As is well known, the sync signal separated by is composed of a vertical sync signal and a horizontal sync signal. here,
For convenience of explanation, it is shown as T _sync . Meanwhile, the luminance signal component of the image separated from the television signal is DAT for convenience.
A signal is illustrated. This DATA signal is input to the shift register 204.

The shift register 204 is for converting the DATA signal serially input in time series into serial / parallel conversion for each line of the image, and based on the control signal T _sft sent from the control circuit 203. Works. In other words, the control signal T _sft is the shift clock of the shift register 204. The data of one line of the serial / parallel-converted image (corresponding to the driving data of n elements of the surface conduction electron-emitting device) is converted into n parallel signals I _{d1 to} I _dn as the shift register 204. Will be output.

The line memory 205 is a storage device for storing data for one line of an image for a required time,
The contents of I _{d1 to} I _dn are appropriately stored according to the control signal T _mry sent from the control circuit 203. The stored content is I
_The signals are output as _{d'1 to} I _d'n and input to the modulation signal generator 207.

The modulation signal generator 207 is a signal source for appropriately driving and modulating each of the surface conduction electron-emitting devices in accordance with each of the image data I _{d'1 to} I _d'n , and outputs the signal. The signal is applied to the surface conduction electron-emitting device in the display panel 201 through the terminals D _{y1 to} D _yn .

As described above, the surface conduction electron-emitting device has a clear threshold voltage for electron emission, and electron emission occurs only when a voltage exceeding the threshold voltage is applied. Further, for a voltage exceeding the threshold voltage, the emission current also changes according to the change in the voltage applied to the surface conduction electron-emitting device. Material of surface conduction electron-emitting device,
The value of the threshold voltage and the degree of change of the emission current with respect to the applied voltage may change by changing the configuration and the manufacturing method. In any case, the following can be said.

That is, when a pulsed voltage is applied to the surface conduction electron-emitting device, no electron emission occurs even if a voltage below the threshold voltage is applied, but a voltage exceeding the threshold voltage is applied. If it does, electron emission occurs. At that time, firstly, it is possible to control the intensity of the output electron beam by changing the peak value of the voltage pulse. Secondly, it is possible to control the total amount of charges of the output electron beam by changing the width of the voltage pulse.

Therefore, as a method of modulating the surface conduction electron-emitting device according to the input signal, there are a voltage modulation method and a pulse width modulation method. In the case of performing the voltage modulation method, the modulation signal generator 207 uses a voltage modulation method circuit that generates a voltage pulse of a constant length, but can appropriately modulate the pulse peak value according to the input data. In the case of performing the pulse width modulation method, the modulation signal generator 207 generates a voltage pulse having a constant peak value, but a circuit of the pulse width modulation method capable of appropriately modulating the pulse width according to the input data is used. To use.

The shift register 204 and the line memory 20
5 may be of a digital signal type or an analog signal type as long as it can perform serial / parallel conversion and storage of an image signal at a predetermined speed.

When the digital signal type is used, it is necessary to convert the output signal DATA of the sync signal separation circuit 206 into a digital signal. This can be done by providing an A / D converter at the output of the sync signal separation circuit 206.

Further, in connection with this, the line memory 20
Depending on whether the output signal of 5 is a digital signal or an analog signal,
The circuit provided in the modulation signal generator 207 is slightly different.

That is, in the case of the voltage modulation method using a digital signal, for example, a well-known D / A conversion circuit may be used as the modulation signal generator 207, and an amplification circuit or the like may be added if necessary. Further, in the case of a pulse width modulation method using a digital signal, the modulation signal generator 207, for example, a high-speed oscillator and a counter (counter) that counts the number of waves output by the oscillator, and the output value of the counter and the output value of the memory. It can be easily configured by using a circuit in which comparators for comparison are combined. Further, 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 may be added.

On the other hand, in the case of the voltage modulation method using an analog signal, the modulation signal generator 207 may be, for example, an amplifier circuit using a well-known operational amplifier or the like, and a level shift circuit or the like may be added if necessary. May be. Further, in the case of the pulse width modulation method using an analog signal, for example, a well-known voltage controlled oscillation circuit (VCO) may be used, and the voltage is amplified to the drive voltage of the surface conduction electron-emitting device as necessary. May be added.

In the image forming apparatus of the present invention having the display panel 201 and the driving circuit as described above, necessary surface conduction type electron emission is obtained by applying a voltage from the terminals D _{x1 to} D _xm and D _{y1 to} D _yn. Electrons can be emitted from the device, a high voltage is applied to the metal back 115 or a transparent electrode (not shown) through the high voltage terminal Hv to accelerate the electron beam, and the accelerated electron beam collides with the fluorescent film 114. By the excitation / light emission generated in (1), television display can be performed according to an NTSC system television signal.

The above-described structure is a schematic structure necessary for obtaining the image forming apparatus of the present invention used for display or the like, and the detailed parts such as the material of each member are limited to the above contents. However, it is appropriately selected so as to suit the purpose of the image forming apparatus. Further, although the NTSC system has been described as the input signal, the image forming apparatus according to the present invention is not limited to this, and other systems such as PAL and SECAM systems may be used, and more scanning lines than these may be used. It is also possible to use a high-definition TV system such as a TV signal such as the MUSE system.

Next, an example of the above-mentioned ladder-type electron source and an image forming apparatus of the present invention using the electron source will be described with reference to FIGS. 11 and 12.

In FIG. 11, 1 is a substrate, 104 is a surface-conduction electron-emitting device, and 304 is a common wiring for connecting the surface-conduction electron-emitting device 104. Ten external wires D _{1 to} D ₁₀ are provided. have.

The surface conduction electron-emitting device 104 is the substrate 1
A plurality of them are arranged in parallel on the top. This is called an element row. A plurality of these element rows are arranged to form an electron source.

Each element row can be independently driven by applying an appropriate drive voltage between the common wiring 304 of each element row (for example, the common wiring 304 of the external terminals D ₁ and D ₂ ). That is, a voltage exceeding the threshold voltage may be applied to the element row where the electron beam is desired to be emitted, and a voltage lower than the threshold voltage may be applied to the element row where the electron beam is not desired to be emitted. Application of the driving voltage, the common wiring D ₂ to D ₉ located at each element rows, the external terminals D ₂ and D ₃ adjacent common wiring 304, i.e. each phase adjacent each phase, D ₄ and D ₅ , D ₆ and D ₇ , and D ₈ and D ₉ common wiring 304 can be integrated into the same wiring.

FIG. 12 is a diagram showing the structure of a display panel 301 provided with the above-mentioned ladder-type electron source, which is another example of the electron source of the present invention.

In FIG. 12, 302 is a grid electrode, 303 is an opening through which electrons pass, D _{1 to} D _m are external terminals for applying a voltage to each surface conduction electron-emitting device, and G ₁ to
G _n is an external terminal connected to the grid electrode 302. Further, the common wiring 304 between each element row is formed on the substrate 1 as an integrated single wiring.

In FIG. 12, the same reference numerals as those in FIG. 8 indicate the same members, and a big difference from the display panel 201 using the electron source of the simple matrix arrangement shown in FIG. The point is that the grid electrode 302 is provided between 116.

The grid electrode 302 is provided between the substrate 1 and the face plate 116 as described above. The grid electrode 302 is capable of modulating the electron beam emitted from the surface conduction electron-emitting device 104, and the electron beam is applied to the stripe-shaped electrode provided orthogonal to the device row in the ladder-type arrangement. To pass
A circular opening 303 is provided for each of the surface conduction electron-emitting devices 104.

The shape and arrangement position of the grid electrode 302 are
It does not necessarily have to be the one shown in FIG. 12, and a large number of openings 303 may be provided in a mesh shape, and the grid electrode 302 may be provided, for example, around or near the surface conduction electron-emitting device 104. Good.

The external terminals D _{1 to} D _m and G _{1 to} G _n are connected to a drive circuit (not shown). Then, by applying a modulation signal for one image line to the columns of the grid electrode 302 in synchronization with the sequential driving (scanning) of the element rows one column at a time, irradiation of each electron beam to the fluorescent film 114 is performed. The image can be displayed line by line.

As described above, the image forming apparatus of the present invention is
An image formation that can be obtained by using the electron source of the present invention in either a simple matrix arrangement or a trapezoidal arrangement and is suitable not only as a display device for the television broadcast described above but also as a display device for a video conference system, a computer, or the like. The device is obtained. Further, it can also be used as an exposure device of an optical printer configured with a photosensitive drum.

[0122]

[Examples and functions]

[Example 1 and Comparative Example 1] As Example 1 of the present invention,
The plane type surface conduction electron-emitting device shown in FIGS. 1A and 1B was manufactured according to the process shown in FIG.

First, on the quartz substrate 1, Ti having a thickness of 5 nm and subsequently Pt having a thickness of 30 nm were formed as thin films for device electrodes by a vacuum evaporation method. Spinner coat a resist on it, expose using a mask for device electrode pattern,
After development, a device electrode pattern of resist was formed.
Next, after removing the excess element electrode thin film by etching, the resist was removed to obtain the element electrodes 2 and 2 ′ having a desired pattern (FIG. 3A).

A Cr film is formed on the entire surface of the device by a sputtering method, a resist is spinner-coated, and a resist pattern for forming a PdO film, which will be described later, is formed by exposing and developing using a photomask to eliminate unnecessary etching. Cr was removed, an opening was formed, and the resist was removed.

Then, an organic Pd complex solution (ccp4230;
Okuno Pharmaceutical Co., Ltd.) is spinner-coated on the above element, and heat treatment is performed at 300 ° C. for 12 minutes. This step 3
Repeated times, Pd which is the first conductive thin film having a desired thickness
An O film 3 was obtained (FIG. 3 (b)).

A pulse width of 0.
1 msec, pulse interval 10 msec, pulse height 0
A rectangular wave pulse voltage gradually increased from V to 14 V at 5 V / min is applied to cause the first crack 22 to pass through the first PdO.
It was formed on the film 3 (FIG. 3C).

Further, the first PdO film 3 and the first crack 2 are formed.
In the same manner as the step of forming the first PdO film 3 on the organic Pd 2, the organic Pd
The complex solution is applied and heat treated to form the second conductive thin film P.
A dO film 4 was obtained (FIG. 2 (d)), and a voltage was similarly applied to form a second crack 23 (FIG. 2 (e)) to obtain the surface conduction electron-emitting device of Example 1. However, in the second PdO film forming step, the application / heat treatment step of the organic Pd complex solution is performed only once.

Example 1 was repeated except that the energization process of the first PdO film was omitted, and the application / heat treatment process of the organic PdO complex solution corresponding to the second PdO film was subsequently performed, and then the energization process was performed. A surface conduction electron-emitting device of Comparative Example 1 having a PdO film of the same thickness was manufactured in the same manner as in.

I _e and I _f of the surface conduction electron-emitting devices produced in Example 1 and Comparative Example 1 were measured by the measurement evaluation system shown in FIG. The applied voltage is a rectangular wave pulse of 14 V, the pulse interval is 10 msec, and the pulse width is 0.1 ms.
ec. The distance between the anode electrode 41 and the surface conduction electron-emitting device is 2 mm, and the voltage of the anode electrode 41 is 1 kV.

Although I _e and I _f are slightly different for each element,
In Example 1, the values of I _e and _{F f} were about 5 times and about 2 times, respectively, larger than those of Comparative Example 1. The fact that the improvement in I _e exceeds the improvement in I _f means that it is possible to design a surface conduction electron-emitting device having sufficient performance with low power consumption, and a very desirable result was obtained.

Example 2 and Comparative Example 2 As a second example of the present invention, an electron source having a simple matrix arrangement shown in FIG. 6 was produced according to FIG. 13, the same reference numerals as those in FIGS. 1 and 6 indicate the same members.

First, a Cr film having a thickness of 5 nm and an A film having a thickness of 600 nm were formed on the washed blue glass substrate 1 by a vacuum deposition method.
After sequentially stacking u films, a photoresist (AZ137
(0; Hoechst) is spin-coated and baked by a spinner, a photomask image is exposed and developed to form a resist pattern of the lower wiring, and the Au / Cr laminated film is wet-etched to be the lower wiring in the X direction. 102 was formed. A silicon oxide film having a thickness of 0.1 μm is stacked on the entire surface of the substrate as an interlayer insulating layer 131 by a high frequency sputtering method to form a photoresist pattern for forming a contact hole, and using this as a mask, the interlayer insulating layer is formed. The contact hole 132 was formed by etching 131. In addition, etching was performed using R ₄ using CF ₄ and H ₂ gas.
It was based on the IE (Reactive Ion Ething) method (a).

Next, a pattern to be the gap between the device electrodes and the device electrodes is formed with a photoresist (RD-2000N-
41; manufactured by Hitachi Chemical Co., Ltd.), and Ti having a thickness of 5 nm and Ni having a thickness of 100 nm were sequentially laminated by a vacuum vapor deposition method. Dissolve the photoresist pattern with an organic solvent,
The i / Ti deposited film was lifted off, and the gap 13 of 2 μm was formed.
Device electrodes 2 and 2 ′ having 3 were obtained (b).

After forming a photoresist pattern for the upper wiring on the device electrodes 2 and 2 ′, Ti having a thickness of 5 nm and a thickness of 1 are formed.
00 nm of Au was sequentially deposited. An unnecessary portion was removed by lift-off to form the Y-direction wiring 103. Next, a resist film was formed so as to cover portions other than the contact holes 132, and Ti having a thickness of 5 nm and Au having a thickness of 500 nm were sequentially laminated by a vacuum evaporation method. By removing unnecessary portions by lift-off, the contact holes 132
Was embedded (c).

In the same manner as in Example 1, Pd of the Cr mask was used.
O pattern is formed, and an organic Pd complex solution (ccp423
0; manufactured by Okuno Seiyaku Co., Ltd.) is spin coated by a spinner and baked at 300 ° C. for 12 minutes to form a PdO film. This operation is repeated three times to make the PdO film have a desired thickness, and then the unnecessary PdO is removed together with the Cr mask by lift-off,
The first PdO film 3 is formed.

As shown in FIG. 7, the Y-direction wirings 103 were commonly connected to the substrate in this state, and the X-direction wirings 102 were subjected to forming processing line by line to form the first cracks 22. The applied pulse has the same waveform as that used in the first embodiment.

A second PdO film 4 was formed in the same manner as the first PdO film forming step. However, PdO is applied and fired only once. Next, the other end of the X-direction wiring on the opposite side is connected to the pulse generator 72 and the same current is applied to the second crack 23.
Was formed (d) to complete the electron source of this example.

A thin film including an electron emitting portion having substantially the same thickness as in Example 2 except that the energization of the first PdO film was omitted and the coating and firing of the organic Pd complex solution was repeated four times. An electron source of Comparative Example 2 having

The electron sources of Example 2 and Comparative Example 2 were attached to the measurement / evaluation system shown in FIG. 14, and all the surface conduction electron-emitting devices were time-sequentially scan-driven. The surface conduction electron-emitting device exhibits a non-linear characteristic that almost no current flows and no electron emission occurs when the voltage applied to the device is below a certain threshold value. Utilizing this property, a drive pulse is applied to the X-direction wiring being driven, and the Y-direction wiring connected to the surface conduction electron-emitting device to be lit is set to the ground level, and the other Y-direction wiring is set to the ground level and the maximum pulse By setting the voltage in the middle (half-selection voltage), electrons can be emitted only to the element at a desired position.

The system of FIG. 14 will be described. In FIG. 14, 14
Reference numeral 1 is a vacuum chamber, which is 5 × 10 ⁻⁵ by an exhaust system (not shown).
Exhausted below Pa. 142 is a window, 1 is an electron source substrate, and 144 is an element body of the electron source. 145,146
Are drive wirings for X-direction and Y-direction wirings. A driver 147 applies an appropriate pulse to the wiring.
Reference numeral 148 denotes an extraction electrode, which is obtained by fitting glass on which an ITO thin film of a transparent electrode is formed into an aluminum frame and applying a phosphor on the lower surface thereof.

A driving voltage of 14 V and a half selection voltage of 7 are applied to each element.
A rectangular wave pulse was applied by the driver 77 so as to attain V. The extraction voltage is 5 kV.

When the light emission of the phosphor due to electron emission was visually observed through the window 142, in the electron source of Comparative Example 2, one end in the X direction (the end to which the pulse generator was not connected during forming) was found. The brightness was the lowest on that line. On the other hand, in the electron source of Example 2, such a tendency that the brightness is different at both ends is not seen, and the variation in the brightness is obviously smaller than that of Comparative Example 2, and the uniformity of the element characteristics is improved. It was confirmed that

In Example 2, as the conductive thin film, Pd was used.
Although an O fine particle film is used, another conductive thin film such as Au is used.
The same effect can be obtained by using a vapor deposition film, a SnO ₂ sputtered film, or the like.

[Third Embodiment] FIG. 15 shows an image forming apparatus constructed by using the electron source of the second embodiment so that image information provided from various image information sources such as television broadcasting can be displayed. FIG. 3 is a diagram showing an example of a display device configured as described above. In the figure, 170 is a display panel, 1
Reference numeral 51 is a display panel drive circuit, 152 is a display controller, 153 is a multiplexer, 154
Is a decoder, 155 is an input / output interface circuit, 1
56 is a CPU, 157 is an image generation circuit, 158 and 159.
And 160 are image memory interface circuits, 161
Is an image input interface circuit, 162 and 163 are TV signal receiving circuits, and 164 is an input unit. (Note that the present display device, when receiving a signal including both video information and audio information, such as a television signal, naturally reproduces audio at the same time as displaying video. Receipt, separation, and reproduction of audio information that is not directly related to features
Descriptions of circuits and speakers related to processing and storage will be omitted. )

Each section will be described below along the flow of the image signal.

First, the TV signal receiving circuit 163 is a circuit for receiving a TV image signal transmitted using a wireless transmission system such as radio waves or spatial optical communication. The system of the TV signal to be received is not particularly limited, and various systems such as NTSC system, PAL system and SECAM system may be used. Further, a TV signal (for example, a so-called high-definition TV such as the MUSE method) including a larger number of scanning lines than these is suitable for taking advantage of the display panel suitable for a large area and a large number of pixels. It is a signal source. TV received by the TV signal receiving circuit 163
The signal is output to the decoder 154.

The image TV signal receiving circuit 162 is a circuit for receiving a TV image signal transmitted using a wired transmission system such as a coaxial cable or an optical fiber. Similar to the TV signal receiving circuit 163, the system of the TV signal to be received is not particularly limited, and the TV signal received by this circuit is also output to the decoder 154.

Further, the image input interface circuit 16
Reference numeral 1 denotes a circuit for capturing an image signal supplied from an image input device such as a TV camera or an image reading scanner, and the captured image signal is output to the decoder 154.

Further, the image memory interface circuit 1
60 is a video tape recorder (hereinafter abbreviated as VTR)
The circuit for fetching the image signal stored in is output to the decoder 154.

Further, the image memory interface circuit 1
Reference numeral 59 is a circuit for capturing the image signal stored in the video disc, and the captured image signal is output to the decoder 154.

The image memory-interface circuit 158 is a circuit for fetching an image signal from a device that stores still image data, such as a so-called still image disc.
4 is output.

Further, the input / output interface circuit 155
Is a circuit for connecting the display device to an external computer, a computer network, or an output device such as a printer. It is of course possible to input / output image data and character / graphic information, and in some cases, input / output control signals and numerical data between the CPU 156 of the display device and the outside.

Further, the image generation circuit 157 receives image data or character / graphic information from the outside via the input / output interface circuit 155, or the CPU 156.
It is a circuit for generating display image data based on image data and character / graphic information output from the output. Inside this circuit, for example, a rewritable memory for accumulating image data and character / graphic information, a read-only memory that stores image patterns corresponding to character codes,
The circuits necessary for image generation, such as a processor for image processing, are incorporated.

The display image data generated by this circuit is output to the decoder 154, but in some cases, it may be output to an external computer network or printer via the input / output interface circuit 155.

Further, the CPU 156 mainly performs operations relating to operation control of the display device and generation, selection, and editing of a display image.

For example, a control signal is output to the multiplexer 153 to appropriately select or combine the image signals to be displayed on the display panel. At that time, a control signal is generated to the display panel controller 152 according to the image signal to be displayed, and the screen display frequency, the scanning method (for example, interlace or non-interlace), the number of scanning lines in one screen, etc. are displayed. The operation of the device is controlled appropriately.

Image data or character / graphic information is directly output to the image generation circuit 157, or an external computer or memory is accessed through the input / output interface circuit 155 to obtain image data or character / figure information.
Enter graphic information.

It should be noted that the CPU 156 may of course be involved in work for purposes other than this. For example, like a personal computer or word processor,
It may be directly related to the function of generating and processing information.

Alternatively, as described above, the computer may be connected to an external computer network via the input / output interface circuit 155, and work such as numerical calculation may be performed in cooperation with an external device.

Further, the input unit 164 has the CPU 156.
The user inputs commands, programs, data, and the like, and various input devices such as a joystick, a bar code reader, and a voice recognition device can be used in addition to a keyboard and a mouse.

Further, the decoder 154 converts various image signals input from the above 157 to 163 into three primary color signals,
Alternatively, it is a circuit for inverse conversion into a luminance signal, an I signal, and a Q signal. In addition, as shown by a dotted line in FIG.
It is desirable that 54 has an image memory inside. This is to handle a television signal that requires an image memory for reverse conversion, such as the MUSE method. Further, the provision of the image memory facilitates the display of a still image, or the image generation circuit 15
This is because, in cooperation with the CPU 7 and the CPU 156, there is an advantage that image processing and editing such as image thinning, interpolation, enlargement, reduction, and composition can be easily performed.

The multiplexer 153 is the CPU
The display image is appropriately selected based on the control signal input from 156. That is, the multiplexer 153 selects a desired image signal from the inversely converted image signals input from the decoder 154 and outputs it to the drive circuit 151. In that case, by switching and selecting image signals within one screen display time, it is possible to divide one screen into a plurality of areas and display different images depending on the areas, as in a so-called multi-screen television. .

Also, the display panel controller 1
Reference numeral 52 is a circuit for controlling the operation of the drive circuit 151 based on a control signal input from the CPU 156.

First, regarding the basic operation of the display panel, for example, a signal for controlling an operation sequence of a power source (not shown) for driving the display panel is output to the drive circuit 151.

Further, regarding the driving method of the display panel, for example, a signal for controlling the screen display frequency and the scanning method (for example, interlace or non-interlace) is output to the drive circuit 151.

In some cases, control signals relating to image quality adjustment such as brightness, contrast, color tone and sharpness of a display image may be output to the drive circuit 151.

The drive circuit 151 is a circuit for generating a drive signal to be applied to the display panel 170. The drive circuit 151 receives an image signal input from the multiplexer 153 and a control signal input from the display panel controller 152. It operates based on.

The functions of the respective parts have been described above. With the configuration illustrated in FIG. 15, the display panel 1 displays image information input from various image information sources in this display device.
70 can be displayed. That is, various image signals such as television broadcast are inversely converted by the decoder 154, appropriately selected by the multiplexer 153, and input to the drive circuit 151. On the other hand, the display controller 152 generates a control signal for controlling the operation of the drive circuit 151 according to the image signal to be displayed. The drive circuit 151 applies a drive signal to the display panel 170 based on the image signal and the control signal. As a result, the image is displayed on the display panel 170. These series of operations are performed by the CPU 1
It is totally controlled by 56.

Further, in this display device, the image memory built in the decoder 154 and the image generation circuit 157.
With the involvement of the CPU 156, not only the selected one of the plurality of image information is displayed, but also the image information to be displayed is enlarged, reduced, rotated, moved, edge emphasized, thinned, interpolated, or the like. It is also possible to perform image processing such as color conversion and aspect ratio conversion of images, and image editing such as combining, erasing, connecting, replacing, and fitting. Further, in the description of this embodiment,
Although not particularly mentioned, a dedicated circuit for processing and editing audio information may be provided as in the above-mentioned image processing and image editing.

Therefore, the present display device is a display device for television broadcasting, a terminal device for a video conference, an image editing device for handling still images and moving images, a computer terminal device, an office terminal device such as a word processor, and a game. It is possible to combine the functions of a machine, etc., and has a very wide range of applications for industrial or consumer use.

Note that FIG. 15 only shows an example of the configuration of a display device using a display panel having a surface conduction electron-emitting device as an electron source, and it is needless to say that the present invention is not limited to this. Yes. For example, of the constituent elements of FIG. 15, circuits relating to functions that are unnecessary for the purpose of use may be omitted. On the contrary, the constituent elements may be added depending on the purpose of use. For example, when the display device is applied as a videophone, it is preferable to add a television camera, a voice microphone, an illuminator, a transmission / reception circuit including a modem, and the like to the constituent elements.

In the present display device, in particular, since it is easy to thin the display panel using the surface conduction electron-emitting device as an electron source, the depth of the display device can be reduced. In addition, a display panel using surface conduction electron-emitting devices as an electron source can easily make a large screen, has high brightness, and has excellent viewing angle characteristics, so that this display device provides a realistic and powerful image. It can be displayed well.

Further, since the electron source of the present invention has uniform electron emission characteristics among the surface conduction electron-emitting devices, the quality of the formed image is high and a high-definition image can be displayed. .

[0174]

As described above, the surface conduction electron-emitting device of the present invention has I _e , I _f , and electron emission efficiency I _e / I _f.
Shows a large and uniform electron emission characteristic. Moreover, the surface conduction electron-emitting device can be easily manufactured without complicated processes such as special electrical control.

Further, in the electron source of the present invention, since the non-uniformity of the electron emission characteristic due to the wiring resistance is suppressed, the brightness of the bright spots corresponding to the respective elements is uniform, and the electron source is used. With this image forming apparatus, it is possible to efficiently form a good image without unevenness. For example, by using a phosphor as an image forming member, a display device such as a high-quality color flat television that is bright with low current can be realized.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of a surface conduction electron-emitting device of the present invention.

FIG. 2 is a diagram showing an example of a manufacturing process of a surface conduction electron-emitting device of the present invention.

FIG. 3 is a diagram showing voltage waveforms in an energization process for manufacturing the surface conduction electron-emitting device of the present invention.

FIG. 4 is a diagram showing a measurement evaluation system for evaluating electron emission characteristics of the surface conduction electron-emitting device of the present invention.

FIG. 5 is a diagram showing electron emission characteristics of the surface conduction electron-emitting device of the present invention.

FIG. 6 is a schematic diagram of a simple matrix electron source of the present invention.

FIG. 7 is a wiring diagram of the electron source of the present invention during forming.

FIG. 8 is a diagram showing an embodiment of an image forming apparatus of the present invention.

FIG. 9 is a diagram showing a fluorescent film used in the image forming apparatus of the present invention.

FIG. 10 is a block diagram of an embodiment of the image forming apparatus of the present invention.

FIG. 11 is a schematic view of a ladder type electron source of the present invention.

FIG. 12 is a diagram showing an image forming apparatus of the present invention using a ladder type electron source.

FIG. 13 is a diagram showing a manufacturing process of the electron source according to the second embodiment of the present invention.

FIG. 14 is a diagram showing a measurement evaluation system of the electron source of the present invention.

FIG. 15 is a block diagram of an application example of the image forming apparatus according to the third embodiment of the present invention.

[Explanation of symbols]

 1 Insulating Substrate 2, 2'Element Electrode 3 First Conductive Thin Film 4 Second Conductive Thin Film 5 Crack 6 Step Forming Part 22 First Crack 23 Second Crack 40 Ammeter 41 Power Supply 42 Ammeter 43 High Power supply 44 Anode electrode 45 Vacuum device 46 Exhaust pump 71 Common electrode 72 Pulse generator 73 Shunt resistance 102 X-direction wiring 103 Y-direction wiring 104 Surface conduction electron-emitting device 105 Connection 111 Rear plate 112 Support frame 113 Glass substrate 114 Fluorescent film 115 Metal back 116 Face plate 118 Envelope 121 Black conductive material 122 Fluorescent substance 131 Interlayer insulating layer 132 Contact hole 133 Gap 141 Vacuum chamber 142 Window 144 Element body 145 X-direction drive wiring 146 Y-direction drive wiring 147 Driver 148 Drawer Electrode 149 Power supply 151 Driving circuit 152 Display panel controller 153 Multiplexer 154 Decoder 155 Input / output interface 156 CPU 157 Image generating circuit 158 Image memory interface 159 Image memory interface 160 Image memory interface 161 Image input memory interface 162 TV signal receiving circuit 163 TV signal receiving circuit 164 Input unit 170 Display panel 201 Display panel 202 Scanning circuit 203 Control circuit 204 Shift register 205 Line memory 206 Synchronous signal separation circuit 207 Modulation signal generator 301 Display panel 302 Grid electrode 303 Opening 304 Common wiring

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Claims (13)

[Claims] 1. A surface-conduction electron-emitting device comprising a conductive thin film formed across a pair of opposing device electrodes, and an electron-emitting portion formed on the thin film located in the gap between the electrodes.
The conductive thin film is composed of at least two layers, a lower layer thin film having a crack substantially at the center of the device electrode gap, and an upper thin film formed on the lower layer crack, and the upper thin film inside the crack of the lower thin film. An electron-emitting device characterized in that cracks are formed therein. 2. The electron-emitting device according to claim 1, wherein the conductive thin film is made of Pd, PdO, or a mixture thereof. 3. The electron-emitting device according to claim 1, wherein the film thickness of the upper layer is smaller than the film thickness of the lower layer. 4. The electron-emitting device according to claim 1, wherein the device electrodes are flat devices formed on the same surface. 5. A vertical type element in which element electrodes are vertically arranged with an insulating layer in between, and a conductive thin film is formed on a side surface of the insulating layer. The electron-emitting device according to item 1. 6. A method of manufacturing a surface conduction electron-emitting device, wherein the step of forming an electron-emitting portion comprises at least forming a first conductive thin film and applying a voltage to the thin film to form a crack. And a step of forming a second conductive thin film on the cracked thin film and applying a voltage again to form the crack, at least once. . 7. The method of manufacturing an electron-emitting device according to claim 6, wherein the conductive thin film is made of PdO. 8. The method for manufacturing an electron-emitting device according to claim 6, further comprising the step of applying a voltage to the conductive thin film to form a crack and then subjecting the thin film to a reduction treatment. 9. An electron source comprising at least one row of elements, which are formed by arranging a plurality of electron-emitting devices according to claim 1 in parallel and connecting them. 10. At least one row of the electron-emitting devices according to any one of claims 1 to 5 is arranged, and wirings for driving the devices are arranged in a matrix. An electron source characterized by being present. 11. A method of manufacturing an electron source, comprising a large number of surface-conduction electron-emitting devices arranged in matrix in which a conductive thin film forming an electron-emitting portion is at least two layers.
When one of the matrix wirings is an X-direction wiring and the other is a Y-direction wiring, the Y-direction wirings are commonly connected and connected to one pole of the voltage applying means, and the X-direction wiring is sequentially connected to the other pole of the voltage applying means. When a voltage is applied to the conductive thin film for each element connected to the same X-direction wiring and a voltage is applied to the second and subsequent thin films, a voltage is applied to the previous thin film. A method for manufacturing an electron source, characterized in that an end portion of the X-direction wiring on the side opposite to is connected to a voltage applying means. 12. At least an electron source according to claim 9,
An image forming apparatus comprising: an image forming member; and a control electrode for controlling an electron beam emitted from each electron emitting element according to an information signal. 13. An image forming apparatus comprising at least the electron source according to claim 10 and an image forming member.