JP3222338B2 - Method of manufacturing electron source and 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 an electron source having a large number of electron-emitting devices, an image forming apparatus to which the electron source is applied, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, two types of electron emitting devices, a thermionic electron source and a cold cathode electron source, are known. The cold cathode electron source includes a field emission type (hereinafter abbreviated as “FE type”), a metal / insulating layer / metal type (hereinafter abbreviated as “MIM type”), a surface conduction electron emission element, and the like.

As an example of the FE type, WPDyke & WWDol
an, "Field emission", Advance inElectron Physics,
8, 89 (1956) or CASpindt, "Physical Propertie
s of thin-film field emission cathodes with molbde
ninum cones ", J. Appl. phys., 47, 52488 (1976), etc. Examples of the MIM type include CAMead," Thetu
nnel-emission amplifier, J. Appl. Phys., 32, 646 (196
1) etc. are known. Examples of surface conduction electron-emitting devices include MIElinson, Radio Eng. Electron Phys., 1
0, (1965) and the like.

[0004] The surface conduction electron-emitting device utilizes the phenomenon that electron emission occurs when a current flows in a small-area thin film formed on a substrate in parallel with the film surface. Examples of the surface conduction electron-emitting device include a device using an SnO ₂ thin film by Elinson et al., A device using an Au thin film [G. Dittmer: “Thin Solid Films”, 9, 317 (1972)],
According to In ₂ O ₃ / SnO ₂ thin film [M. Hartwell and
CGFonstad: "IEEETrans. ED Conf.", 519 (1975)
], With carbon thin film [Hisashi Araki et al .: Vacuum, 2nd
6, No. 1, p. 22 (1983)].

[0005] A typical device configuration of these surface conduction electron-emitting devices is described in the aforementioned M.A. FIG. 20 shows a device configuration of the Hartwell. In the figure, reference numeral 1001 denotes a substrate.
1004 is a conductive thin film, both ends of which are element electrodes 1002,
An electron emission portion 1005 is formed by a metal oxide thin film or the like formed by sputtering in an H-shaped pattern to become 1003, and by an energization process called energization forming described later. The distance L1 between the device electrodes 1002 and 1003 in the figure is set to 0.5 to 1 mm, and the width W is set to 0.1 mm.

Heretofore, in these surface conduction electron-emitting devices, it has been general to form an electron-emitting portion 1005 on the conductive thin film 1004 in advance by an energization process called energization forming before electron emission. That is, the energization forming means applying a direct current voltage or a very slowly increasing voltage, for example, about 1 V / min, to both ends of the conductive thin film 1004 and energizing the conductive thin film 1004 to locally destroy, deform or deteriorate the conductive thin film 1004. The purpose is to form the electron emitting portion 1005 in a state of being electrically high in resistance. In the electron emitting portion 1005, a crack is generated in a part of the conductive thin film 1004, and electrons are emitted from the vicinity of the crack. The surface conduction type electron-emitting device that has been subjected to the energization forming process applies a voltage to the above-described conductive thin film 1004 and causes a current to flow through the device.
It emits more electrons.

Furthermore, a step called activation is usually introduced after the completion of the energization forming step. An object of the present invention is to increase the amount of emitted electrons by continuously supplying a constant voltage to the surface conduction electron-emitting device having a high resistance by the energization forming for a predetermined time.

The above-described surface conduction electron-emitting device has an advantage that a large number of devices can be arranged and formed over a large area because the structure is simple and the production is easy. Therefore, various applications are being studied to make use of this feature. For example, a charge beam source, a display device, and the like can be given. As an example in which a large number of surface conduction electron-emitting devices are arranged and formed, a ladder-type arrangement is used, in which surface conduction electron-emitting devices are arranged in parallel, and both ends of each element are interconnected (also referred to as a common interconnect).
An electron source in which a number of connected lines are arranged in a large number of rows (for example, Japanese Patent Application Laid-Open No.
-2833749, JP-A-1-257552 and the like). In particular, in image forming apparatuses such as display apparatuses, flat panel display apparatuses using liquid crystal have recently become widespread in place of CRTs. However, they are not self-luminous and must have a backlight. Therefore, development of a self-luminous display device has been desired. Examples of the self-luminous display device include an image forming device that is a display device in which an electron source having a large number of surface conduction electron-emitting devices and a phosphor that emits visible light by electrons emitted from the electron source are combined. (Eg, US Pat. No. 5,066,883).

[0009]

As described above, an electron source having a large number of electron-emitting devices is expected to be applied to a large-area image display device or the like. However, in a situation where the resolution of an image is increasing, it is required to increase the number of pixels, that is, to arrange a larger number of electron-emitting devices.
For that purpose, it is necessary to further improve the reliability of wiring connected to each electron-emitting device in order to drive each electron-emitting device.

Accordingly, an object of the present invention is to provide an electron source for improving the reliability of wiring for driving an electron-emitting device, an image forming apparatus to which the electron source is applied, and a method for manufacturing the same. .

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

According to a method of manufacturing an electron source of the present invention, a plurality of pairs of device electrodes constituting an electron-emitting device are arranged in a matrix on a substrate, and a voltage is applied between the device electrodes. In the method of manufacturing an electron source for forming a wiring for emitting electrons from an electron emitting portion of the electron emitting element, the step of forming the wiring may include the step of forming one of the pair of device electrodes arranged in a row direction. Forming a plurality of row wirings electrically connected to the device electrodes; forming an insulating structure at least in a predetermined portion on each of the row wirings; Forming a plurality of column wirings electrically connected to the other element electrode, intersecting the row wirings with the insulating structure interposed therebetween, and forming each of the row wirings when forming the insulating structure. Directional wiring
Forming a first interlayer insulating layer in the column wiring direction;
A second interlayer insulating layer is formed under each column-direction wiring along
By doing so , the thickness at the intersection of each of the row direction wirings and each of the column direction wirings is formed to be thicker than other portions.

Further, each of the row wirings and each column wiring may be formed by a thick film printing method.

[0020]

According to a method of manufacturing an image forming apparatus of the present invention, an electron source is manufactured by any one of the above-described methods of manufacturing an electron source of the present invention, and the electron source is connected to the electron source via a support frame. characterized in that it constitutes the envelope of the image forming member on which an image is formed by electrons emitted from the electron-emitting devices collide with opposed.

Further, the image forming member may be formed of a phosphor film containing a phosphor that emits light when the electrons emitted from the electron-emitting device collide.

[0023]

In the electron source of the present invention configured as described above,
In order to drive the electron-emitting devices arranged in a matrix, a plurality of row-direction wirings and a plurality of column-direction wirings are formed to intersect with each other, but between each row-direction wiring and each column-direction wiring. An insulating structure is provided, so that the row direction wiring and the column direction wiring are electrically insulated. Here, since the thickness of the insulating structure is thick at the intersection of each row-direction wiring and each column-direction wiring, insulation between the row-direction wiring and the column-direction wiring is ensured, and even in a large-area electron source. The reliability of the wiring is improved. As described above, it is easy to partially increase the thickness of the insulating structure by configuring the insulating structure with a plurality of insulating layers.

Further, by forming each wiring or insulating layer by a thick film printing method, each wiring or insulating layer can be formed without the need for a photolithography step, and the process of forming each wiring or insulating layer can be shortened. Is achieved.

Further, in the case where the insulating structure is composed of a plurality of insulating layers, the insulating layer includes a first insulating layer formed along each row direction wiring for each row direction wiring and a column for each column direction wiring. With the configuration including the second insulating layer formed along the direction wiring, the insulating layer always exists above each row direction wiring and below each column direction wiring. As a result, even if there is a displacement between the row direction wiring and the column direction wiring,
The insulation between the two is more reliably ensured. This also increases the tolerance for displacement between the two, and facilitates positioning. In addition, since the width of each insulating layer can be made as small as the width of the wiring, the area of a portion controlled by the wiring is reduced. As a result, high-density wiring becomes possible, and high-density arrangement of electron-emitting devices is achieved.

On the other hand, instead of forming the second insulating layer along each column-direction wiring for each column-direction wiring, each second
In this case, the width of the second insulating layer is made larger than the width of the column direction wiring, so that the tolerance for the positional deviation of the column direction wiring is large. It will be.

Particularly preferred among the electron-emitting devices used in the electron source of the present invention are surface conduction electron-emitting devices. The surface conduction electron-emitting device has a simple structure and is simple to manufacture, and a large-area electron-emitting device can be easily manufactured. In recent years, particularly in a situation where an inexpensive image forming apparatus with a large screen is required, the electron emitting device is particularly suitable.

Since the image forming apparatus of the present invention uses the electron source of the present invention having the above-described wiring structure, the reliability of the wiring is improved, and the formation of an image by the emission of electrons from the electron-emitting device is improved. Done. In particular, the insulating structure includes a first insulating layer formed along each row wiring for each row wiring and a second insulating layer formed along each column wiring for each column wiring. According to the configuration, since the electron-emitting devices can be arranged at a high density as described above, the number of pixels per unit area is increased, and an image forming apparatus having high resolution is achieved.

The image forming member can be applied to an image display device by using a phosphor film containing a phosphor that emits light when electrons emitted from an electron-emitting device collide.

[0030]

Next, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 1 is a perspective view of a main part of a first embodiment of an electron source according to the present invention, and shows a substrate on which a large number of surface conduction electron-emitting devices 9 are arranged in a matrix. 1 is shown. Each electron-emitting device 9 includes a pair of device electrodes 2 and 3 opposed to each other.
And a conductive thin film 4 for connecting the device electrodes 2 and 3 for forming an electron-emitting portion.

On the substrate 1, the light passes through one of the device electrodes 3 of the electron-emitting devices 9 arranged in the Y direction (row direction), and
A plurality of first wiring layers 6 as row wirings electrically connected to one of the element electrodes 3 arranged in
A plurality of first wires as column-direction wirings, which pass over the other device electrodes 2 of the electron-emitting devices 9 arranged in the direction (column direction) and are electrically connected to the other device electrodes 2 arranged in the X direction. 2
Wiring layers 8 are provided in a matrix.

The surface of each first wiring layer 6 is
While each of the second wiring layers 8 is covered with a first interlayer insulating layer 7a formed along the second wiring layer 6, a second interlayer insulating layer formed along the second wiring layer 8 is formed. 7b, the first wiring layer 6 and the second wiring layer 8 are insulated from each other by a first interlayer insulating layer 7a and a second interlayer insulating layer 7b. Due to the first interlayer insulating layer 7a and the second interlayer insulating layer 7b, the thickness of the insulating layer at the intersection between the first wiring layer 6 and the second wiring layer 8 is larger than the thickness at other portions. The insulating structure is also thickened. Here, in order to electrically connect the other device electrode 2 of the electron-emitting device 9 and the second wiring layer 8, the second interlayer insulating layer 7 b has a position corresponding to the position of the one device electrode 2. And a contact hole (not shown) penetrating through the second interlayer insulating layer 7b.
Is provided. By forming the second wiring layer 8 so as to fill this contact hole, the second wiring layer 8 is formed.
Is electrically connected to the other element electrode 2.

As will be described later in detail, a scanning signal for scanning a row of the electron-emitting devices 9 arranged in the X direction in accordance with an input signal is applied to the second wiring layer 8. Are electrically connected to the scanning signal generating means. On the other hand, the first wiring layer 6 includes a modulation signal generating means (not shown) for applying a modulation signal for modulating each of the rows of the electron-emitting devices 9 arranged in the Y direction according to the input signal. It is electrically connected. Further, the driving voltage applied to each element of the electron-emitting device 9 is supplied as a difference voltage between a scanning signal and a modulation signal applied to the element.

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

Here, a surface conduction electron-emitting device suitable for the present invention will be described.

FIGS. 6A and 6B show the structure of a basic surface conduction electron-emitting device suitable for the present invention. FIG. 6A is a plan view and FIG. 6B is a cross-sectional view. . Hereinafter, a basic configuration of an electron-emitting device suitable for the present invention will be described with reference to FIG.

In FIG. 6, two element electrodes 102 and 103 are arranged on a substrate 101 at an interval from each other.
By connecting each of the device electrodes 102 and 103, the electron-emitting portion 10 is connected.
5 is provided.

As the substrate 101, quartz glass, glass having a reduced impurity content such as Na, blue plate glass, a glass substrate obtained by laminating SiO ₂ formed on blue plate glass by sputtering or the like, and ceramics such as alumina are used. Can be

As a material for the opposing element electrodes 102 and 103, a general conductor material is used.
Cr, Au, Mo, W, Pt, Ti, Al, Cu, Pd
Metal or alloy such as Pd, Ag, Au, Ru
It is appropriately selected from a printed conductor composed of a metal such as O ₂ or Pd—Ag or a metal oxide and glass, a transparent conductor such as In ₂ O ₃ / SnO _2, a semiconductor conductor material such as polysilicon, or the like.

The element electrode interval L, the element electrode length W, the shape of the conductive thin film 104, and the like are designed according to the applied form and the like. The device electrode interval L is preferably from several hundred angstroms to several hundred micrometers, and more preferably, from several micrometers to several tens of micrometers depending on the voltage applied between the device electrodes 102 and 103 and the electric field intensity capable of emitting electrons. Meters. The device electrode length W is preferably from several micrometers to several hundred micrometers depending on the resistance value and electron emission characteristics of the electrode. The thickness d of the device electrodes 102 and 103 is several hundred angstroms to several micrometers.

The structure of the substrate 1 is not limited to the structure shown in FIG.
01, the conductive thin film 104 and the opposing device electrode 10
The electrodes may be laminated in the order of 2, 103.

In order to obtain good electron emission characteristics, the conductive thin film 104 is particularly preferably a fine particle film composed of fine particles. The thickness of the conductive thin film 104 depends on the step coverage of the device electrodes 102 and 103, the device electrodes 102 and 103, and the like. The resistance is appropriately set depending on the resistance value between 103 and the energizing forming conditions described later, and is preferably from several Angstroms to several thousand Angstroms, particularly preferably from 10 Angstroms to 500 Angstroms.
0 ³ is from 10 ⁷ Ω / □ sheet resistance value of.

The material constituting the conductive thin film 104 is Pd, Pt, Ru, Ag, Au, Ti, In, C
metals such as u, Cr, Fe, Zn, Sn, Ta, W and Pb, PdO, SnO ₂ , In ₂ O ₃ , PbO and Sb ₂ O
₃ , oxides such as HfB ₂ , ZrB ₂ , LaB ₆ , Ce
Borides such as B ₆ , YB ₄ and GdB ₄ , TiC, ZrC,
Carbides such as HfC, TaC, SiC, WC, TiN, Z
Examples include nitrides such as rN and HfN, semiconductors such as Si and Ge, carbon, and AgMg, NiCu, and PbSn.

The fine particle film described here is a film in which a plurality of fine particles are gathered, and has a fine structure not only in a state in which the fine particles are individually dispersed and arranged, but also in a state in which the fine particles are adjacent to each other or overlap each other ( (Including islands), and the particle size of the fine particles is from several Angstroms to several thousand Angstroms, preferably from 10 Angstroms to 200 Angstroms.

The electron-emitting portion 105 is a crack formed in a part of the conductive thin film 104 and in a state of being in an electrically high resistance state, and has a thickness, a film quality, a material, and an energization forming described later. And so on.
Further, the conductive fine particles may have a particle diameter of several Å to several hundred Å. The conductive fine particles are similar to some or all of the elements of the material constituting the conductive thin film 104. Further, the electron emitting portion 105 and the conductive thin film 104 in the vicinity thereof may contain carbon or a carbon compound.

Various methods are conceivable as a method for manufacturing the above-mentioned surface conduction electron-emitting device. One example is shown in FIG.

The manufacturing method will be described below with reference to FIGS. 6 and 7.

(1) After sufficiently washing the substrate 101 with a detergent, pure water and an organic solvent, depositing an element electrode material on the substrate 101 by a vacuum deposition method, a sputtering method, or the like, and then depositing the element electrode material on the substrate 101 by photolithography. Electrode 10
2 and 103 are formed (FIG. 7A).

As a method for forming the device electrodes 102 and 103, a thick film printing method may be used. As a material when the printing method is used, an organic metal paste (MO
D) and the like.

(2) An organic metal solution is applied to the substrate 101 on which the device electrodes 102 and 103 are provided and left to form an organic metal thin film. The organic metal solution is a solution of an organic metal compound containing the metal of the material of the conductive thin film 104 as a main element. Thereafter, the organic metal thin film is heated and baked, and is patterned by lift-off, etching, or the like to form a conductive thin film 104 (FIG. 7B).
Here, the method has been described by using the method of applying an organic metal solution, but the present invention is not limited to this, and it is formed by 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. There is also.

(3) Subsequently, the device electrodes 102 and 103
In the meantime, when electricity is supplied by a power supply (not shown), the conductive thin film 10
An electron emitting portion 105 having a changed structure is formed at the portion 4 (FIG. 7C). This energization processing is called energization forming, and the conductive thin film 104 is locally destroyed, deformed or deteriorated by the energization forming, and a portion where the structure is changed is called an electron emission portion 105. FIG. 8 shows an example of the voltage waveform of the energization forming.

The voltage waveform is particularly preferably a pulse waveform. When a pulse having a constant pulse peak value is applied continuously (FIG. 8A), a voltage pulse is applied while increasing the pulse peak value. (FIG. 8B). First, the case where the pulse peak value is a constant voltage will be described.

T1 and T2 in FIG. 8A are the pulse width and pulse interval of the voltage waveform, respectively.
1 is 1 microsecond to 10 milliseconds, T2 is 10 microseconds to 100 milliseconds, and the peak value of the triangular wave (peak voltage at the time of energization forming) is appropriately selected according to the above-described form of the surface conduction electron-emitting device. And a suitable degree of vacuum, for example, 1
Under a vacuum atmosphere of about 0 ^-5 Torr, the voltage is applied for several seconds to several tens minutes. Note that the waveform applied between the element electrodes 102 and 103 is not limited to a triangular wave, and a desired waveform such as a rectangular wave may be used.

T1 and T2 in FIG. 8B are the same as those in FIG. 8A, and the peak value of the triangular wave (peak voltage during energization forming) is increased by, for example, about 0.1 V steps. It is applied under a suitable vacuum atmosphere. In this case, the end of the energization forming process is as follows.
When a voltage that does not locally destroy or deform the conductive thin film 104, for example, a resistance of 1 M ohm or more is shown during the pulse interval T2, the energization forming is terminated.

(4) Next, a process referred to as an activation process is preferably performed on the element after the energization forming. The activation step means, for example, a process of repeating the application of a pulse with a pulse peak value of a constant voltage at a degree of vacuum of about 10 ^-4 to 10 ^-5 Torr, as in the energization forming, and exists in a vacuum. By depositing carbon or a carbon compound from an organic substance, the element current I flowing through the conductive thin film 104 is increased.
f, a process in which the emission current Ie emitted from the electron emission unit 105 changes significantly. Device current If and emission current Ie
, The activation step ends when the emission current Ie is saturated, for example. Further, the pulse peak value is preferably an operation drive voltage.

The carbon and the carbon compound referred to here are graphite (both single and polycrystalline) and amorphous carbon (a mixture of amorphous carbon and polycrystalline graphite). The thickness is preferably 500
Angstrom or less, more preferably 300 angstrom or less.

(5) The thus-produced electron-emitting device is placed in a vacuum atmosphere having a degree of vacuum higher than the degree of vacuum in the energization forming step and the activation step, and is preferably operated and driven.
More preferably, the device is heated to 80 ° C. to 150 ° C. in a vacuum atmosphere with a higher degree of vacuum, and then driven to operate.

The vacuum atmosphere having a degree of vacuum higher than that of the energization forming step and the activation processing is, for example, about 10
A vacuum degree having a vacuum degree of ^-6 Torr or more, more preferably an ultra-high vacuum system in which carbon or a carbon compound is not substantially newly deposited. Accordingly, this makes it possible to suppress the further deposition of carbon or carbon compound, and the device current If and the emission current I
e becomes stable.

The characteristic evaluation of the electron-emitting device manufactured by the above-described configuration and manufacturing method and suitable for the present invention will be described with reference to FIGS.

FIG. 9 is a schematic configuration diagram of a measurement evaluation device for measuring the electron emission characteristics of the device having the configuration shown in FIG. In FIG. 9, the same components as those in FIG.
The same reference numerals are used. Reference numeral 151 denotes a power supply for applying a device voltage Vf to the electron-emitting device; 150, an ammeter for measuring a device current If flowing through the conductive thin film 104 between the device electrodes 102 and 103; An anode electrode for capturing the emission current Ie emitted from the electron emission unit 105; 153, a high-voltage power supply for applying a voltage to the anode electrode 154; 152, an electron emission unit 1 of the device.
This is an ammeter for measuring the emission current Ie emitted from the device 05.

The electron-emitting device and the anode 1
Numeral 54 is installed in a vacuum device, and the vacuum device is provided with equipment necessary for a vacuum device such as an exhaust pump 156 and a vacuum gauge, so that measurement and evaluation of this element can be performed under a desired vacuum. I have. In addition, the exhaust pump 156 includes a normal high vacuum device system including a turbo pump and a rotary pump, and further includes an ultra-high vacuum device system including an ion pump. The entire vacuum device 155 and the substrate can be heated up to 200 ° C. by a heater (not shown). Therefore, the present measuring apparatus can also perform the steps after the energization forming described above. The voltage of the anode electrode 154 is 1 kV
-10 kV, and the distance H between the anode electrode 154 and the electron-emitting device was measured in the range of 2 mm to 8 mm.

FIG. 10 shows a typical example of the relationship between the emission current Ie, the device current If, and the device voltage Vf measured by the measurement and evaluation apparatus shown in FIG. Since the emission current Ie is significantly smaller than the device current If, it is shown in arbitrary units in FIG.
It is about one in one.

As is apparent from FIG. 10, the surface conduction electron-emitting device suitable for the present invention has three characteristic characteristics with respect to the emission current Ie.

First, the present device has a device voltage Vf equal to or higher than a certain voltage (called a threshold voltage, Vth in FIG. 10).
Is applied, the emission current Ie sharply increases, while the emission current Ie is hardly detected below the threshold voltage Vth. That is, it is a nonlinear element having a clear threshold voltage Vth with respect to the emission current Ie.

Second, since the emission current Ie depends on the device voltage Vf, the emission current Ie can be controlled by the device voltage Vf.

Third, the amount of charge discharged by the anode electrode 154 depends on the time during which the device voltage Vf is applied.
That is, the amount of charge captured by the anode electrode 154 is
It can be controlled by the time for applying the element voltage Vf.

Because of the characteristic characteristics of the surface conduction electron-emitting device suitable for the present invention as described above,
The electron emission characteristics can be easily controlled even in an electron source in which a plurality of electron emission elements are arranged, an image forming apparatus, and the like.
It can be applied to various fields.

An example of a more preferable characteristic in which the element current If monotonically increases with respect to the element voltage Vf (referred to as MI characteristic) is shown by a solid line in FIG. The voltage-controlled negative resistance (VC
(Referred to as a NR characteristic) in some cases (shown by a broken line in FIG. 10). The characteristics of the device current If depend on the manufacturing method, measurement conditions at the time of measurement, and the like. In this case, also in this case, the electron-emitting device has the three characteristics described above.

Further, in the above-described evaluation apparatus, a voltage is applied between the device electrodes
When more electrons are emitted and a voltage is applied to the anode electrode 154 by the high-voltage power supply 153, the emitted electrons
The positive electrode side of the voltage applied to the element (in FIG. 9, the element electrode 102
Side). Such a radiation characteristic corresponds to the substrate 1
It is considered that the potential distribution in a plane parallel to 01 becomes asymmetric with respect to the electron-emitting portion 105.

Next, a manufacturing process of the electron source of this embodiment shown in FIG. 1 will be described with reference to FIGS. 2 to 5 show one electron-emitting device 9 and its wiring as a representative.

First, as shown in FIG. 2, device electrodes 2 and 3 are formed on a substrate 1 which has been sufficiently cleaned in advance. Usually, since the conductive thin film 4 for forming the electron emitting portion is a film that is significantly thinner than the respective wiring layers 6 and 8, problems such as wettability and step holding properties are avoided, and the conductive thin film 4 for forming the electron emitting portion is formed. The device electrodes 2 and 3 are provided to improve the electrical connection between the conductive thin film 4 and each of the wiring layers 6 and 8. Therefore, each of the wiring layers 6 and 8
In the case where is formed of a thin film by, for example, a sputtering method or the like, the device electrodes 2 and 3 are not necessarily provided, and can be formed simultaneously with the formation of each of the wiring layers 6 and 8 described later.

The device electrodes 2 and 3 may be formed by a method using a vacuum system such as a vacuum evaporation method, a sputtering method, or a plasma CVD method, or by printing and firing a thick film paste in which a metal component and a glass component are mixed in a solvent. There is a method of forming a thick film. In order to shorten the manufacturing process, the device electrodes 2 and 3 may be formed by a thick film printing method that does not require a photolithography process. In order to improve the wettability with (see FIG. 1), a thinner film is desirable.
Therefore, when the thick film printing method is used, it is preferable to use a so-called MOD paste composed of an organometallic compound as the paste used at that time. Of course, other film forming methods may be used. The constituent materials of the device electrodes 2 and 3 are not particularly limited as long as they are electrically conductive substances.

In order to further simplify the manufacturing process of the electron source, it is possible to simultaneously form the device electrodes 2 and 3 and an electrode (not shown) for connection to an external circuit. In this case as well, it is simple to use a thick film printing method, but it goes without saying that a film can be formed by a sputtering method or the like and a pattern can be formed by a photolithography technique.

In this embodiment, a soda lime glass substrate was used as the substrate 1 and the device electrodes 2 and 3 were formed by a thick film printing method. The paste used at this time was a MOD paste, and the metal component was Au. The printing method is a screen printing method. After printing, drying is performed at 70 ° C. for 10 minutes, and then main firing is performed. The firing temperature is 550 ° C. and the peak retention time is about 8 minutes. The thickness of one device electrode 2, 3 after printing and firing was 0.3 μm or less, and the interval between the device electrodes 2, 3 was 2 μm.

Next, as shown in FIG.
The first wiring layer 6 is formed so as to be electrically connected to one of the device electrodes 2 and 3. The method for forming the first wiring layer 6 can be the same as the method for forming the device electrodes 2 and 3.
Unlike the above, in order to reduce the electric resistance, it is preferable that the film thickness is large. Therefore, as a method for forming the first wiring layer 6, it is preferable to use a thick film printing method. Any paste material may be used as long as it is conductive, such as a noble metal such as Ag, Au, Pt, or Pd, Cu,
A base metal such as Ni, Al, or Cr, or a fine particle composed of a mixture thereof dispersed in a vehicle is used. Further, those having high viscosity and high thixotropy are suitable for forming fine wires. Of course, thin-film wiring can be applied, but it takes more time to increase the film thickness than the thick-film printing method.

In this embodiment, a thick film screen printing method is used. The paste used was Noritake's NP-
4028A.

After forming the first wiring layer 6, as shown in FIG. 4, the first interlayer insulating layer 7a is formed so as to cover the first wiring layer 6.
Is formed, and then a second interlayer insulating layer 7b passing over the other device electrode 2 and intersecting with the first interlayer insulating layer 7a is formed. As a result, the first interlayer insulating layer 7 is formed at the intersection between the first wiring layer 6 and the second wiring layer 8 formed in the next step.
a and the second interlayer insulating layer 7b are present, and the thickness of that portion is greater than the thickness of the other portions. First
As a constituent material of the interlayer insulating layer 7a and the second interlayer insulating layer 7b, for example, a thick film paste containing no metal component such as a SiO ₂ thin film or a material in which glass fine particles or oxide fine particles are dispersed in a vehicle is used. Any material that can maintain insulation, such as a film, may be used. When forming using the thick film printing method, the first interlayer insulating layer 7a can be formed using the same screen plate as the first wiring layer 6, and the second interlayer insulating layer 7b can be formed using the second wiring layer. It can be formed using the same screen plate as the layer 8. In addition, by making the insulating structure a two-layer structure as described above, it is easy to partially increase the thickness of the insulating structure.

In this embodiment, the first interlayer insulating layer 7a and the second interlayer insulating layer 7b are formed by a thick film screen printing method. As the paste, a paste containing PbO as a main component and a glass binder mixed was used. The firing temperature is 550 ° C. and the peak retention time is about 15 minutes. printing,
First and second interlayer insulating layers 7a and 7b after firing
At the intersection with was 30 micrometers or less.

Then, as shown in FIG. 5, the interlayer insulating layer 7
A second wiring layer 8 is formed thereon. The second wiring layer 8
It is electrically connected to the other element electrode 2 through a contact hole (not shown) provided in advance in second interlayer insulating layer 7b. The thickness of the second wiring layer 8 is also preferably thick for the same reason as that of the first wiring layer 6, and the same forming method as that of the first wiring layer 6 can be applied. . In this embodiment, a thick film screen printing method was used.

Thus, the matrix wiring portion is completed. Of course, the paste material, the printing method, and the like are not limited to those described above.

Finally, as shown in FIG. 1, the pair of device electrodes 2 and 3 are connected to form a conductive thin film 4 for forming an electron-emitting portion.
Is formed, and the conductive thin film 4 is subjected to an energization forming process to form an electron emission portion, thereby completing an electron source. A conventional method can be applied as it is to the method of forming the conductive thin film 4 and the energization forming process.

Specifically, organic palladium (CCP4230, manufactured by Okuno Pharmaceutical Co., Ltd.) is spin-coated by a spinner across the pair of device electrodes 2 and 3 and then heated to 300 ° C.
For 10 minutes to form a conductive thin film 4 made of Pd. The conductive thin film 4 thus formed
Is composed of fine particles containing Pd as a main element, has a thickness of 10 nm, and has a sheet resistance of 5 × 10 ⁴ Ω / □.
Met. Note that the fine particle film described here is a film in which a plurality of fine particles are aggregated, and has a fine structure not only in a state where the fine particles are individually dispersed and arranged, but also in a state where the fine particles are adjacent to each other or overlapped (including an island shape). ), And the particle diameter means the diameter of the fine particles whose particle shape can be recognized in the above state. By patterning the film containing Pd as a main element using a photolithography method, the element manufacturing process up to the energization forming process is completed.

In this embodiment, the energization forming process
As shown in FIG. 8 (a), this was performed by continuously applying a pulse having a pulse peak value at a constant voltage. The applied pulse at this time has a pulse width T1 of 1 millisecond, a pulse interval T2 of 10 milliseconds, a peak value of 14 V, and about 10 ^-6 T
This was performed for 60 seconds under a vacuum atmosphere of orr. The electron-emitting portion thus produced was in a state in which fine particles containing palladium as a main component were dispersed and arranged, and the average particle size of the fine particles was 3 nanometers.

As described above, the first interlayer insulating layer 7a
By providing the second interlayer insulating layer 7b, the insulating structure has a two-layer structure at the intersection of the first wiring layer 6 and the second wiring layer 8, and as a result, the thickness of the insulating structure is increased. Thereby, the insulation between the first wiring layer 6 and the second wiring layer 8 is secured with a simple insulating structure. Moreover, the first wiring layer 6
Since only the first interlayer insulating layer 7a and the second interlayer insulating layer 7b need to be formed in accordance with the pattern of the second wiring layer 8, the formation of the insulating structure is easy.

Further, since an insulating structure always exists above the first wiring layer 6 and below the second wiring layer 8, the insulating structure of the first wiring layer 6 or the second wiring layer 8 may be formed. Even if the alignment is slightly shifted, the probability that the first wiring layer 6 and the second wiring layer 8 are short-circuited is significantly reduced. Therefore,
Even in the case of a large-area electron source, the reliability of the wiring between the first wiring layer 6 and the second wiring layer 8, particularly the reliability of the insulation is improved, and the first wiring layer 6 and the second wiring layer 8 In this case, the tolerance for the positional deviation becomes large, and the alignment between the two becomes easy, so that the manufacturing time can be reduced and the yield can be improved.

Further, if only the second interlayer insulating layer 7b is provided without providing the first interlayer insulating layer 7a, an error due to an alignment error between the first wiring layer 6 and the second wiring layer 8 may occur. In order to reduce the short circuit, the width of the second interlayer insulating layer 7b needs to be larger than the width of the second wiring layer 8. However, according to the present configuration, the first wiring layer 6 and the second wiring layer 8 have a large tolerance for displacement, so that the second wiring layer 8 has a second tolerance as compared with the case where only the second interlayer insulating layer 7b is provided. Can be reduced in width. Therefore, the area of the portion controlled by the wiring is reduced, and high-density wiring can be performed, so that the device electrodes 2 and 3 and the electron-emitting device 9 can be arranged at a higher density.

Next, an example of an image forming apparatus using the electron source shown in FIG. 1 will be described with reference to FIGS. FIG. 11 is a basic configuration diagram of an example of a display panel of an image forming apparatus using the electron source shown in FIG.
FIG. 13 is a diagram showing an example of the arrangement of phosphors in the phosphor film of the display panel shown in FIG. 11. FIG. 13 shows an image forming apparatus using the electron source shown in FIG. FIG. 2 is a block diagram of a drive circuit of an example of performing display by using a display.

In FIG. 11, the rear plate 81 includes
An electron source 80 similar to that shown in FIG. 1 is fixed. The electron emitting elements 87 of the electron source 80 arranged in an m × n matrix form x wirings 88 and n each composed of m wirings, each constituting a simple matrix wiring.
It is connected to a y-wiring 89 composed of two wirings. Here, x wiring 88 corresponds to second wiring layer 8 and second interlayer insulating layer 7b shown in FIG. 1, and y wiring 89 corresponds to first wiring 6 and first interlayer insulating layer shown in FIG. Corresponds to layer 7a.

The electron source 80 has a fluorescent film 84 as an image forming member and a metal back 85 on the inner surface of a glass substrate 83.
Are formed facing each other with a support frame 86 interposed therebetween. Electron source 80 and metal back 8
During the period 5, a high voltage for accelerating the electron beam emitted from the electron source 80 is applied by a power supply (not shown). The rear plate 81, the support frame 86, and the face plate 82 are air-tightly fixed (sealed) to each other, and the rear plate 81, the support frame 86, and the face plate 82 form an envelope 90. The sealing of the rear plate 81, the support frame 86 and the face plate 82 is performed by applying frit glass or the like to the fixed surfaces of each other,
It is performed by baking at 00 ° C. to 500 ° C. for 10 minutes or more. Each of the x wirings 88 has m external terminals Dx1, Dx2,..., Dx provided on the support frame 86, respectively.
m are connected, and each of the y wirings 89 has n external terminals Dy1, Dy2,... provided on the support frame 86, respectively.
Connected to Dyn.

As described above, the envelope 90 includes the face plate 82, the support frame 86, and the rear plate 81. The rear plate 81 is provided mainly for the purpose of reinforcing the strength of the electron source 80. If the electron source 80 itself has a sufficient strength, the separate rear plate 81 is not always necessary. The support frame 86 is directly sealed to the electron source 80, and the face plate 82, the support frame 86 and the electron source 8 are sealed.
0 may constitute the envelope 90. Also,
By providing a support (not shown) called a spacer between the face plate 82 and the rear plate 81, the structure of the envelope 90 having sufficient strength against the atmospheric pressure can be obtained.

In the case of monochrome, the phosphor film 84 is made of only a phosphor which is an image forming member. In the case of color, as shown in FIG. 12, depending on the arrangement of the phosphor, a black stripe called a black stripe or a black matrix is used. It is composed of a conductive material 84b and a phosphor 84a. The purpose of providing the black stripes and the black matrix is to make the color mixing and the like inconspicuous by making the painted portions between the phosphors 84a of the three primary color phosphors necessary for color display less noticeable. The purpose is to suppress a decrease in contrast due to external light reflection. The material of the black stripe is not limited to a commonly used material containing graphite as a main component, as long as it is conductive and has little light transmission and reflection. As a method of applying the phosphor onto the glass substrate 83, a precipitation method or a printing method is used regardless of monochrome or color. Further, in the case of a collar, a slurry method can be used.

A metal back 85 is usually provided on the inner side of the fluorescent film 84. The purpose of the metal back 85 is
Preventing the electrons applied to the phosphor 84a from being charged; improving the brightness by mirror-reflecting the light toward the inner surface side of the light emitted from the phosphor 84a toward the face plate 82; , And protection of the phosphor 84a from damage due to collision of negative ions generated in the envelope 90. The metal back 85 can be manufactured by performing a smoothing process (usually called filming) on the inner surface of the fluorescent film 84 after the fluorescent film 84 is manufactured, and then depositing Al by vacuum evaporation or the like.

The face plate 82 may be provided with a transparent electrode (not shown) on the outer surface of the fluorescent film 84 in order to further enhance the conductivity of the fluorescent film 84.

At the time of performing the above-described sealing, in the case of color, the phosphors 84b of each color must correspond to the electron-emitting devices 87, and therefore it is necessary to perform sufficient alignment.

When the rear plate 81, the support frame 86 and the face plate 82 are sealed with each other to form the envelope 90, the envelope 90 is exhausted by an exhaust system through an exhaust pipe (not shown).
The inside is evacuated to a degree of vacuum of about 10 ⁻⁷ Torr, and the envelope 9 is evacuated.
0 is sealed. In addition, getter processing may be performed in order to maintain the degree of vacuum after sealing the envelope 90. This is because immediately before or after sealing of the envelope 90, the envelope 9 is heated by a heating method such as resistance heating or high-frequency heating.
This is a step of heating a getter (not shown) arranged at a predetermined position within 0 to form a deposited film. The getter usually contains Ba or the like as a main component, and maintains a vacuum degree of, for example, 10 <-5> to 10 <-7> Torr by the adsorption action of the deposited film. Steps after the energization forming process of the electron-emitting device 87 are appropriately set.

Next, a schematic configuration of a driving circuit for performing television display based on an NTSC television signal will be described.
This will be described with reference to the block diagram of FIG. Reference numeral 191 is the display panel shown in FIG. 11, 192 is a scanning circuit, 193 is a control circuit, 194 is a shift register, 19
5 is a line memory, 196 is a synchronization signal separation circuit, 197
Denotes a modulation signal generator, V _x, V _a is a DC voltage source, respectively.

[0098] Hereinafter, will be described the function of each part, the display panel 191 is first is connected to an external electric circuit through terminals Dx1 to Dxm, and Dy1 to Dyn, and a high-voltage terminal H _v. The terminals Dx1 to Dxm sequentially drive electron sources provided in the display panel 191, that is, electron emission element groups arranged in a matrix of m rows and n columns in a matrix, one row at a time (n elements). A scanning signal for moving is applied.

On the other hand, to the terminals Dy1 to Dyn, a modulation signal for controlling the output electron beam of each of the electron-emitting devices in one row selected by the scanning signal is applied. Further, the high-voltage terminal H _v, the DC voltage source V _a, for example, a DC voltage of 10kV is applied, which is sufficient energy to excite the phosphors to the electron beams output from the electron-emitting devices Is an accelerating electrode for providing

Next, the scanning circuit 192 will be described.
Scanning circuit 192, m number of switching elements in the interior as it has a (in the figure, it is shown schematically in to no S1 Sm), each switching element, the output voltage or 0V (the ground level of the DC voltage source V _x ) Is selected and electrically connected to the terminals Dx1 to Dxm of the display panel 191. Each of the switching elements S1 to Sm operates based on a control signal output from the control circuit 193.
It can be easily configured by combining the switching elements as described above.

In the case of the present embodiment, the DC voltage source Vx _supplies a drive voltage applied to an unscanned element based on the characteristics (electron emission threshold voltage) of the electron emission element. It is set so as to output a constant voltage lower than the emission threshold voltage.

The control circuit 193 has a function of matching the operation of each unit so that appropriate display is performed based on an externally input image signal. A synchronization signal T _SYNC sent from a synchronization signal separation circuit 196 described below.
T _SCAN and T _SFT and T
Generates _MRY control signals.

The synchronizing signal separating circuit 196 is a circuit for separating a synchronizing signal component and a luminance signal component from an NTSC television signal input from the outside. As is well known, a frequency separating (filter) is used. With the circuit,
It can be easily configured. Sync signal separation circuit 196
Are separated from each other by a vertical synchronizing signal and a horizontal synchronizing signal, as is well known. However, for convenience of explanation, the synchronizing signal is illustrated as a _TSYNC signal. On the other hand, the luminance signal component of the image separated from the television signal is referred to as DATA for convenience.
This signal is input to the shift register 194.

The shift register 194 is for serially / parallel-converting the DATA signal input serially in time series for each line of an image, and converts the DATA signal into a control signal T _SFT sent from the control signal 193. (Ie, the control signal T _SFT may be a shift clock of the shift register 194).
The data for one line of the serial / parallel-converted image (corresponding to the drive data for n electron-emitting devices)
The shift register 194 outputs n parallel signals Id1 to Idn.

The line memory 195 is a storage device for storing data of one line of an image for a required time only, and stores the contents of Id1 to Idn as appropriate according to a control signal T _MRY sent from the control circuit 193. . The stored contents are output as I'd1 to I'dn and input to the modulation signal generator 197.

The modulation signal generator 197 is a signal source for appropriately driving and modulating each of the electron-emitting devices in accordance with each of the image data I'd1 to I'dn. Or display panel 1 through Dyn
The voltage is applied to the electron-emitting device in 91.

As described above, the electron-emitting device according to the present invention has the following basic characteristics with respect to the emission current Ie. That is, as described above, electron emission has a clear threshold voltage Vth, and electron emission occurs only when a voltage higher than Vth is applied. For a voltage equal to or higher than the electron emission threshold, the emission current also changes in accordance with the change in the voltage applied to the element. The value of the electron emission threshold voltage Vth and the degree of change of the emission current with respect to the applied voltage may be changed by changing the material, configuration, and manufacturing method of the electron emission element. The same can be said.

That is, when a pulse-like voltage is applied to the device, for example, when a voltage lower than the electron emission threshold is applied, no electron emission occurs, but when a voltage higher than the electron emission threshold is applied. Outputs an electron beam. At that time, first, it is possible to control the intensity of the output electron beam by changing the peak value Vm of the pulse. Second, it is possible to control the total amount of charge of the output electron beam by changing the pulse width Pw.

Accordingly, as a method of modulating the electron-emitting device in accordance with the input signal, a voltage modulation method, a pulse width modulation method, and the like can be mentioned.
As the modulation signal generator 197, a voltage modulation type circuit that generates a voltage pulse of a fixed length but appropriately modulates the peak value of the pulse according to input data is used.

In order to implement the pulse width modulation method,
As the modulation signal generator 197, a pulse width modulation type circuit that generates a voltage pulse having a constant peak value and appropriately modulates the width of the voltage pulse according to input data is used.

Through the series of operations described above, television display can be performed using the display panel 191. In addition,
Although not specifically described in the above description, the shift register 1
The digital memory 94 or the line memory 195 may be of a digital signal type or an analog signal type, as long as the serial / parallel conversion and storage of the image signal are performed at a predetermined speed.

When the digital signal type is used, it is necessary to convert the output signal DATA of the synchronization signal separation circuit 196 into a digital signal. This is provided with an A / D converter at the output of the synchronization signal separation circuit 196. Needless to say, it is easily possible. In connection with this, the line memory 1
It goes without saying that the circuit used for the modulation signal generator 197 is slightly different depending on whether the output signal of 95 is a digital signal or an analog signal. That is, in the case of a digital signal, in the case of the voltage modulation method, for example, a well-known D / A conversion circuit may be used as the modulation signal generator 197, and an amplification circuit or the like may be added as necessary. In the case of the pulse width modulation method, the modulation signal generator 197 compares, for example, a high-speed oscillator, a counter for counting the number of waves output from the oscillator, and an output value of the counter with an output value of the line memory 195. If a circuit combining a comparator is used, those skilled in the art can easily configure the circuit. If necessary, an amplifier for voltage-amplifying the pulse-width-modulated signal output from the comparator to the drive voltage of the electron-emitting device may be added.

On the other hand, in the case of the analog signal, in the case of the voltage modulation method, for the modulation signal generator 197, for example, an amplifier circuit using a well-known operational amplifier or the like may be used.
If necessary, a level shift circuit or the like may be added.
In the case of the pulse width modulation method, for example, a well-known voltage controlled oscillator (VCO) may be used, and an amplifier for amplifying the voltage up to the drive voltage of the electron-emitting device may be added as necessary. Is also good.

In the image display device completed as described above, electrons are emitted by applying a voltage to each of the electron-emitting devices 87 of the electron source 80 through the terminals Dx1 to Dxm and Dy1 to Dyn, so that the high-voltage terminal H through _v
A high voltage is applied to the metal back 85 or the transparent electrode (not shown) to accelerate the electron beam and cause it to collide with the fluorescent film 84,
An image can be displayed by exciting and emitting light.
An electron source 80 having a wiring structure as shown in FIG.
Is used, the reliability of the wiring to the electron-emitting device 87 becomes high, and good image display can be performed. Also,
Since the density of the wirings and the electron-emitting devices 87 can be increased, the number of pixels per unit area is increased, and an image forming apparatus having high resolution is achieved.

The configuration described above is a schematic configuration necessary for manufacturing a suitable image forming apparatus used for display and the like. For example, detailed portions such as materials of each member are not limited to the above-described contents. Is appropriately selected so as to be suitable for the use of the image forming apparatus. Also, the NTSC system has been described as an example of an input signal, but the present invention is not limited to this, and PAL, SEC
Various systems such as the AM system may be used, and a TV signal (for example, a high-definition TV including the MUSE system) including a large number of scanning lines may be used.

(Second Embodiment) FIG. 14 is a perspective view of a main part of a second embodiment of the electron source according to the present invention. Also in the present embodiment, similarly to the first embodiment, the insulating structure between the first wiring layer 206 and the second wiring layer 208 is configured by the first interlayer insulating layer 207a and the second interlayer insulating layer 207b. However, the arrangement of both is different from the first embodiment. That is, the width of the second interlayer insulating layer 207b is made larger than the width of the second wiring layer 208, and the width of the first interlayer insulating layer 207b is increased.
a, the second interlayer insulating layer 207 b and the first wiring layer 206
And at the intersection. As a result, the thickness of the insulating structure at the intersection between the first wiring layer 206 and the second wiring layer 208 is larger than the thickness at other portions. Other configurations may be the same as in the first embodiment, and a description thereof will not be repeated.

Next, the manufacturing process of the electron source of this embodiment will be described.

First, as shown in FIG. 15, after sufficiently washing a substrate 201 made of soda lime glass, device electrodes 202 and 203 are formed on the substrate 201. In this embodiment, as a method of forming the device electrodes 202 and 203,
A thick film printing method was used. The used paste is a MOD paste, and the metal component is Pt. The printing method is a screen printing method. After printing, drying is performed at 70 ° C. for 10 minutes, and then main firing is performed. The firing temperature is 550 ° C. and the peak retention time is about 8 minutes. Device electrode 20 after printing and firing
The film thickness of 2,203 was 0.25 micrometers or less. At this time, electrodes for connection to an external circuit (not shown) were formed at the same time, and the process was shortened by one process.

Next, as shown in FIG. 16, a first wiring layer 206 passing over one element electrode 203 is formed in the same manner as in the first embodiment, and the first wiring layer 206 and one element electrode 203 are formed. An electrical connection with 203 was obtained.

After the formation of the first wiring layer 206, FIG.
As shown in FIG. 3, the first wiring layer 2 passes over the other device electrode.
A second interlayer insulating layer 207b that intersects with 06 is formed.
Further, as shown in FIG. 18, a first interlayer insulating layer 207a is formed on the second interlayer insulating layer 207b at the intersection between the first wiring layer 206 and the second interlayer insulating layer 107b. I do. The method for forming the first interlayer insulating layer 207a and the second interlayer insulating layer 207b is the same as in the first embodiment.
Thick film screen printing was used. As the paste, a paste obtained by mixing PbO as a main component and a glass binder and a resin was used. The firing temperature is 550 ° C. and the peak retention time is about 15 minutes. First interlayer insulating layer 2 after printing and firing
The thickness at the intersection of 07a and the second interlayer insulating layer 207b was 30 micrometers or less. After the formation of the second interlayer insulating layer 207b or the formation of the first interlayer insulating layer 207a, the other element electrode 202 and a second wiring to be formed in the next step are formed on the second interlayer insulating layer 207b. A contact hole (not shown) for electrical connection with the layer 208 is formed. In addition, the width of the first interlayer insulating layer 107a and the width of the second interlayer insulating layer 207b are set to be larger than the width of the second wiring layer 208 in consideration of the displacement at the time of forming the second wiring layer 208. Is preferred.

As shown in FIG. 19, the second wiring layer 2 is formed on the first interlayer insulating layer 207a and the second interlayer insulating layer 207b along the second interlayer insulating layer 207b.
08 is formed. Since the contact hole is formed in the first interlayer insulating layer 207a as described above, the formation of the second wiring layer 208 allows the other device electrode 202 to be formed.
Are electrically connected to the second wiring layer 208. As a method for forming the second wiring layer 208, a method similar to the method for forming the first wiring layer 206 can be applied.

Thus, the matrix wiring portion is completed. Of course, the paste material, the printing method, and the like are not limited to those described above.

Finally, as shown in FIG. 14, a pair of device electrodes 202 and 203 are connected to form a conductive thin film 204 for forming an electron-emitting portion, and the conductive thin film 204 is subjected to an energization forming process. To form an electron emission portion, and an electron source is completed.

As described above, the first wiring layer 206
A second interlayer insulating layer 207b along the second wiring layer 208 between the first wiring layer 208 and the second interlayer insulating layer 207b and the second wiring layer 208; By forming the first interlayer insulating layer 207a, the thickness of the insulating structure is increased at the intersection between the first wiring layer 206 and the second wiring layer 208, and the first wiring layer 206 and the second Of the wiring layer 208 is secured. As a result, the reliability of the wiring of the first wiring layer 206 and the wiring of the second wiring layer 208 is improved. In addition, the first interlayer insulating layer 207a
Is formed only in a portion necessary for ensuring insulation between the first wiring layer 206 and the second wiring layer 208, so that the material of the wiring layer is minimized, and as a result, the manufacturing cost is reduced. can do. Further, the first interlayer insulating layer 207a
If the width of the second wiring layer 208 and the width of the second interlayer insulating layer 207b are larger than the width of the second wiring layer 208,
8 is facilitated, the manufacturing time is reduced, and the yield is improved.

In this embodiment, the second interlayer insulating layer 207b
Although an example in which the first interlayer insulating layer 207a is formed thereon has been described above, a second interlayer insulating layer 207b may be formed on the first interlayer insulating layer 207a as in the first embodiment.

In each of the above-described embodiments, the contact holes are formed in the second interlayer insulating layers 7b and 207b in order to electrically connect the other element electrodes 2 and 202 to the second wiring layers 8 and 208. Is shown, but the configuration for electrically connecting the other device electrodes 2, 202 and the second wiring layers 8, 208 is not limited to this. For example, the second interlayer insulating layers 7b and 207b can be formed in a pattern divided on the other device electrodes 2 and 202, and the second wiring layers 8 and 208 can be formed on the other device electrodes 2 and
It can also be provided as having a protruding pattern that directly contacts the 202.

Further, as is clear from the embodiments described above, the electron source according to the present invention basically uses a cold cathode type electron-emitting device as an electron-emitting device. Type electron-emitting device is used.
Cold cathode type electron-emitting devices can be precisely positioned and formed on a substrate by using a manufacturing technique such as photolithography or etching. Therefore, a large number of cold-cathode electron-emitting devices can be arranged at minute intervals. Moreover, conventional CRT
As compared with the hot cathode used in such a method, the cathode itself and its peripheral portion can be driven at a relatively low temperature, so that an electron source having a finer arrangement pitch can be easily realized.

Examples of such a cold cathode type electron-emitting device include an MIM type, an FE type, and a surface conduction type, and among them, a surface conduction type electron-emitting device is particularly preferable. That is, the thickness of the insulating layer and the upper electrode needs to be controlled relatively precisely in the MIM type electron-emitting device, and the tip shape of the needle-shaped electron-emitting portion is precisely controlled in the FE type electron-emitting device. There is a need to. For this reason, these elements have a relatively high manufacturing cost, and it is sometimes difficult to manufacture a large-area element due to limitations in the manufacturing process. On the other hand, the surface conduction type electron-emitting device has a simple structure and a simple structure, and a large-area electron-emitting device can be easily manufactured. In recent years, particularly in a situation where a large-area and inexpensive display device is required, it can be said that the cold-cathode type electron-emitting device is particularly suitable.

Further, the electron source of the present invention can be applied to a case where a member to be irradiated with emitted electrons is a member other than an image forming member, such as an electron microscope, and an electron beam which does not specify a member to be irradiated. It can also take the form of a generator.

Further, in each of the embodiments described above, an image display device for displaying an image has been described as an example of an image forming device. However, according to the concept of the present invention, for example, a photosensitive drum and a light emitting diode are used. It can also be used as an alternative light source, such as a light emitting diode of a configured optical printer. In this case, the image forming member is not limited to a substance that directly emits light, such as the phosphor used in the above-described embodiment, and a member that forms a latent image by electron charging may be used. it can.

[0131]

Since the present invention is configured as described above, it has the following effects.

The electron source and the method of manufacturing the same according to the present invention include an insulating structure between a plurality of row-direction wirings and a plurality of column-direction wirings for applying a driving voltage to the electron-emitting devices arranged in a matrix. By forming the cross section to have a large thickness, even in a large-area electron source, the insulation between the two can be ensured, and the reliability of the wiring can be improved. As described above, it is easy to partially increase the thickness of the insulating structure if the insulating structure is constituted by a plurality of insulating layers.

By forming each wiring and insulating layer by a thick film printing method, each wiring and insulating layer can be formed without the need for a photolithography step. Can be

Further, when the insulating structure is composed of a plurality of insulating layers, the insulating layer is formed by a first insulating layer formed along each row direction wiring for each row direction wiring, and a column formed by each column direction wiring. By using the second insulating layer formed along the directional wiring, the tolerance for the positional deviation between each row wiring and each column wiring can be increased. as a result,
The alignment between the two is also facilitated, so that the manufacturing time can be reduced and the yield can be improved. In addition, since the width of each insulating layer can be made as small as the width of the wiring, high-density wiring becomes possible, and electron-emitting devices can be arranged at high density.

On the other hand, instead of forming the second insulating layer along each column-direction wiring for each column-direction wiring, each second
In this case, the width of the second insulating layer is made larger than the width of the column-direction wiring, thereby increasing the tolerance for the positional deviation of the column-direction wiring. can do.

In particular, by using a surface conduction type electron-emitting device as the electron-emitting device used in the electron source of the present invention, the structure is simple, the production is simple, and a large-area device can be easily produced.

Since the image forming apparatus of the present invention uses the electron source of the present invention having the above-described wiring structure, the reliability of the wiring is improved, and as a result, an image is formed by the emission of electrons from the electron-emitting device. Can be performed favorably. In particular, the insulating structure includes a first insulating layer formed along each row wiring for each row wiring and a second insulating layer formed along each column wiring for each column wiring. In the configuration, the electron-emitting devices can be arranged at a high density as described above, so that a high-resolution image forming apparatus can be obtained.

Further, the image forming member can be applied to an image display device by using a phosphor film containing a phosphor that emits light when electrons emitted from the electron-emitting device collide.

In the method of manufacturing an image forming apparatus according to the present invention, an electron source is manufactured by the above-described method of manufacturing an electron source according to the present invention, so that an image forming apparatus with high wiring reliability can be easily manufactured. Can be.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of a first embodiment of an electron source according to the present invention.

FIG. 2 is a view for explaining a manufacturing process of the electron source shown in FIG. 1 and shows a state in which device electrodes are formed.

FIG. 3 is a view for explaining a manufacturing process of the electron source shown in FIG. 1 and shows a state where a first wiring layer is formed.

FIG. 4 is a view for explaining a manufacturing process of the electron source shown in FIG. 1 and shows a state where an interlayer insulating layer is formed.

FIG. 5 is a view for explaining a manufacturing process of the electron source shown in FIG. 1 and shows a state where a second wiring layer is formed.

FIGS. 6A and 6B are diagrams showing a configuration of a basic surface conduction electron-emitting device suitable for the present invention, wherein FIG. 6A is a plan view and FIG. 6B is a cross-sectional view.

FIG. 7 is a view for explaining an example of a manufacturing process of the surface conduction electron-emitting device shown in FIG.

FIG. 8 is a diagram showing an example of a voltage waveform applied at the time of energization forming performed when forming an electron emission portion in a surface conduction electron-emitting device.

FIG. 9 is a schematic configuration diagram of a measurement evaluation device for measuring the electron emission characteristics of the device having the configuration shown in FIG.

10 is a graph showing a typical example of a relationship between an emission current Ie, an element current If, and an element voltage Vf measured by the measurement evaluation device shown in FIG.

11 is a basic configuration diagram of an example of a display panel of an image forming apparatus using the electron source shown in FIG.

12 is a diagram showing an example of the arrangement of phosphors on the phosphor film of the display panel shown in FIG. 11;

FIG. 13 is a block diagram of a driving circuit in which an image is formed in accordance with an NTSC television signal by an image forming apparatus using the electron source shown in FIG. 1;

FIG. 14 is a perspective view of a main part of a second embodiment of the electron source according to the present invention.

FIG. 15 is a view for explaining the manufacturing process of the electron source shown in FIG. 14, and shows a state where element electrodes are formed.

FIG. 16 is a view for explaining the manufacturing process of the electron source shown in FIG. 14, and shows a state where a first wiring layer is formed.

FIG. 17 is a view for explaining the manufacturing process of the electron source shown in FIG. 14, showing a state where a first interlayer insulating layer is formed.

FIG. 18 is a view for explaining the manufacturing process of the electron source shown in FIG. 14, and shows a state where a second interlayer insulating layer is formed.

FIG. 19 is a diagram for explaining the manufacturing process of the electron source shown in FIG. 14, showing a state where a second wiring layer is formed.

FIG. 20 is a view showing a typical device configuration of a conventional surface conduction electron-emitting device.

[Explanation of symbols]

 1, 101, 201 substrate 2, 3, 102, 103, 202, 203 element electrode 4, 104 conductive thin film 6, 206 first wiring layer 7a, 207a first interlayer insulating layer 7b, 207b second interlayer insulation Layer 8, 208 Second wiring layer 9, 87, 209 Electron emission device 80 Electron source 81 Rear plate 82 Face plate 83 Glass substrate 84 Phosphor film 84a Phosphor 84b Black conductive material 85 Metal back 86 Support frame 87 y wiring 88 x Wiring 90 Enclosure 105 Electron emission section 150, 152 Ammeter 151 Power supply 153 High voltage power supply 154 Anode electrode 155 Vacuum device 156 Exhaust pump 191 Display panel 192 Scanning circuit 193 Control circuit 194 Shift register 195 Line memory 196 Synchronous signal separation circuit 197 Modulation Signal generation circuit

Claims (4)

(57) [Claims] 1. A plurality of pairs of device electrodes constituting an electron-emitting device are arranged in a matrix on a substrate, and a voltage is applied between the device electrodes to emit electrons from an electron-emitting portion of the electron-emitting device. In the method of manufacturing an electron source for forming a wiring for forming a plurality of row-directional wirings, the step of forming the wiring includes a plurality of row-directional wirings electrically connected to one of the pair of element electrodes arranged in a row direction. Forming an insulating structure at least in a predetermined portion on each of the row direction wirings; and forming a plurality of electrically connected to the other of the pair of device electrodes arranged in the column direction. Forming a column-directional wiring intersecting with the row-directional wiring with the insulating structure interposed therebetween, wherein, when forming the insulating structure, a first wiring is provided on each of the row-directional wirings.
Forming an interlayer insulating layer of
Forming a second interlayer insulating layer under each column-directional wiring.
A method of manufacturing an electron source , wherein the thickness at the intersection of each row-direction wiring and each column-direction wiring is thicker than other portions. 2. The method for manufacturing an electron source according to claim 1 , wherein each of the row-direction wirings and each of the column-direction wirings are formed by a thick film printing method. 3. An electron source is manufactured by the method for manufacturing an electron source according to claim 1 , wherein electrons emitted from an electron-emitting device of the electron source collide with the electron source via a support frame. A method for manufacturing an image forming apparatus, comprising forming an envelope by arranging image forming members on which an image is formed by opposing. The method according to claim 4, wherein said image forming member, a manufacturing method of an image forming apparatus according to claim 3, electrons emitted from the electron emission element is composed of a phosphor layer containing a phosphor which emits light by colliding.