JP2000223014A - Manufacture of electron source and device thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of an electron source capable of reducing dispersion of element characteristics of a plurality of surface conductive emitting elements, and a device thereof. SOLUTION: Resistance of conductive films formed on a substrate is respectively detected (S3). A minimum voltage (Vmin) and a maximum voltage (Vmax) to be applied are determined corresponding to a minimum value (Rmin) and a maximum value (Rmax) of detected resistances (S4). As a voltage increases in the range from the minimum voltage to the maximum voltage determined in the above processes, a pulse voltage is applied to each of the conductive films in a vacuum and an electron emitting part is formed on the conductive films.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing an electron source in which a large number of electron-emitting devices each having a conductive film having an electron-emitting portion between electrodes are arranged on a substrate.

[0002]

2. Description of the Related Art Conventionally, two types of electron-emitting devices using a thermionic electron-emitting device and a cold-cathode electron-emitting device have been known. Cold cathode electron-emitting devices include a field emission type (hereinafter, referred to as “FE type”), a metal / insulating layer / metal type (hereinafter, referred to as “MIM type”), and a surface conduction type emission device.

As an example of the FE type, for example, WP Dyke
& WW Dolan, “Field emission”, Advance in Ele
ctron Physics, 8, 89 (1956) or CA Spind
t, “Physical properties of thin-film field emissi
on cathodes with molybdeniumcones ”, J. Appl. Phy
s., 47, 5248 (1976).

[0004] Examples of the MIM type include, for example, C.I.
A. Mead, “Operation of tunnel-emission Devices,
J. Appl. Phys., 32,646 (1961) and the like are known.

[0005] As the surface conduction type emission element, for example, M.
I. Elinson, Radio E-ng. Electron Phys., 10, 1290,
(1965) and other examples described later.

[0006] The surface conduction electron-emitting device utilizes a phenomenon in which an electron is emitted when a current flows in a small-area thin film formed on a substrate in parallel with the film surface. Examples of the surface conduction electron-emitting device include a device using an SnO2 thin film by Elinson et al., And a device using an Au thin film [G. Dittmer: “Thin Solid Films”, 9,317 (1)
972)] and those based on In2O3 / SnO2 thin films [M. Hart
well and CG Fonstad: "IEEE Trans. ED Conf."
519 (1975)] and those using carbon thin films [Hisashi Araki
Others: Vacuum, Vol. 26, No. 1, 22 (1983)].

As a typical example of these surface conduction electron-emitting devices, the above-mentioned M.P. FIG. 14 schematically shows a device configuration of Hartwell. In the figure, reference numeral 201 denotes a substrate. Reference numeral 204 denotes a conductive thin film having an H-shaped pattern,
The electron emission portion 205 is formed of a metal oxide thin film or the like formed by sputtering, and is subjected to an energization process called energization forming described later. In addition, the device electrode interval L1 in the figure
Is set to 0.5 to 1 mm, and W 'is set to 0.1 mm.

Conventionally, in these surface conduction electron-emitting devices, the electron emission portion 20 is formed on the conductive thin film 204 by an energization process called energization forming before electron emission.
It was common to form 5. That is, the energization forming means that a direct current voltage or a very slowly increasing voltage, for example, about 1 V / min, is applied to both ends of the conductive thin film 204 to energize, and the conductive thin film 204 is locally broken and deformed. Alternatively, the electron-emitting portion 205 may be altered to be in an electrically high-resistance state. The electron-emitting portion 205 has a crack in a part of the conductive thin film 204. When a voltage is applied to both ends of the electron-emitting portion 205 and a current flows through the element, the electron is emitted from the vicinity of the crack. Is performed.

The above-described M.P. Apart from the Hartwell device,
The applicant of the present application forms a pair of opposing element electrodes formed of a conductor on an insulating base, forms a conductive film connecting the two electrodes separately from these element electrodes, and forms the conductive film by conducting forming. An element having an electron emitting portion has been proposed. As a method of such energization forming, a method of applying a pulse voltage is disclosed in, for example, JP-A-4-28139, and a method of gradually increasing the peak value of the pulse voltage is described in, for example, JP-A-6-141670 and JP-A-7-18297.
No. 0, JP-A-7-192614 and the like.

As a method for manufacturing an electron source, the present applicant disclosed in Japanese Patent Application Laid-Open No. 8-083071 that, in a forming step of forming an electron emitting portion in a conductive thin film, a crack in a conductive film serving as an electron emitting portion was formed. A method of manufacturing a surface conduction electron-emitting device in which a forming step is performed in an atmosphere that promotes reduction or aggregation to reduce the width is proposed.

The above-mentioned surface conduction electron-emitting device has an advantage that a large number of devices can be arranged and formed over a large area since the structure is simple and the production is easy. Therefore, various applications that make use of this feature are being studied. For example,
Examples include a charged beam source and a display device. As an example in which a large number of surface conduction electron-emitting devices are arranged and arranged, as will be described later, a surface conduction electron-emitting device is arranged in parallel, and both ends of each element are connected by wiring (also referred to as common wiring). Are arranged in many rows (for example, JP-A-64-031332, JP-A-1-283737).
JP-A-2-257552, etc.). In recent years, particularly in image forming apparatuses such as display apparatuses, flat-panel display apparatuses using liquid crystal have become widespread instead of CRTs. However, they are not self-luminous and must have a backlight. Therefore, development of a self-luminous display device has been desired. As such a self-luminous display device,
2. Description of the Related Art An image forming apparatus, which is a display apparatus in which an electron source having a large number of surface conduction emission devices arranged thereon and a phosphor that emits visible light by electrons emitted from the electron source, is exemplified (for example, US Pat. No. 5,066,883). ).

[0012]

However, in the conventional energization forming process, when the forming voltage is small, a sufficient crack is not generated in the element, and when the forming voltage is large, an excessive current flows through the element. I will. Therefore, the appropriate value of the forming voltage is narrowed. However, when there is a variation in element resistance among the elements, if the same forming voltage is applied and the processing is performed, the shapes of the cracks and the island structures serving as the electron emission portions vary from element to element, and the element characteristics are non-uniform. There was a problem of becoming.

In the forming process in which the forming voltage is increased stepwise in an atmosphere that promotes reduction or coagulation, if the forming voltage is gradually increased from around 0 V, the elements are formed sequentially from the element having the smallest element resistance. There is a problem that the conductive film is reduced or agglomerated before a necessary voltage is applied to the element having a large resistance, forming failure occurs, and an electron emission portion is not formed. In particular, when an attempt is made to form an electron-emitting device by arranging a large number of conductive thin films, the above-mentioned problem has been prominent.

SUMMARY OF THE INVENTION The present invention has been made in view of the above conventional example, and has as its object to provide a method and apparatus for manufacturing an electron source in which variations in element characteristics of a plurality of electron-emitting devices are reduced.

Another object of the present invention is to provide a method and an apparatus for manufacturing an electron source capable of suppressing variations in element characteristics of the electron source due to variations in resistance of the conductive film.

Another object of the present invention is to prevent the conductive film from being reduced or agglomerated before a voltage required for forming an electron-emitting portion is applied to the conductive film during forming. An object of the present invention is to provide a method and an apparatus for manufacturing an electron source.

[0017]

In order to achieve the above object, an apparatus for manufacturing an electron source according to the present invention has the following arrangement. That is, an apparatus for manufacturing an electron source in which a large number of electron-emitting devices each having a conductive film having an electron-emitting portion between electrodes are arranged on a substrate, and the electron-emitting device includes a conductive film provided on the substrate. Detecting means for detecting each resistance; and a minimum voltage (Vm) to be applied according to a minimum value (Rmin) and a maximum value (Rmax) of the resistance value detected by the detecting means.
in) and voltage determining means for determining a maximum voltage (Vmax), and applying a voltage to each of the conductive films by continuously increasing the voltage from the minimum voltage in an atmosphere of a predetermined degree of vacuum in the substrate; Forming means for forming an electron emission portion in the conductive film.

In order to achieve the above object, a method for manufacturing an electron source according to the present invention comprises the following steps. That is, a method for manufacturing an electron source in which a large number of electron-emitting devices each having a conductive film having an electron-emitting portion between electrodes are arranged on a substrate, wherein a detecting step of detecting each resistance of the conductive film And the minimum value of the resistance value detected in the detection step (R
min) and a maximum value (Rmax) in accordance with a minimum voltage (Vmin) and a maximum voltage (Vmax) to be applied, and a step of continuously increasing the voltage from the minimum voltage to increase the conductivity. And a forming step of applying a voltage to each of the conductive films to form an electron emission portion in the conductive film.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is applied to a method of manufacturing an electron source having a plurality of electron-emitting devices each having a conductive thin film having an electron-emitting portion between electrodes. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic sectional view of an element for explaining an example of a method of manufacturing an electron source according to an embodiment of the present invention.
FIG. 3 is a plan view showing an example of a surface conduction electron-emitting device manufactured by the manufacturing method of the present embodiment.

In these figures, 1 is a substrate, 2 and 3 are device electrodes, 4 is a conductive thin film, and 5 is an electron emitting portion.

Examples of the substrate 1 include quartz glass, glass having a reduced impurity content such as Na, blue plate glass, a glass substrate obtained by laminating SiO 2 formed on a blue plate glass by sputtering or the like, ceramics such as alumina, and a Si substrate. Can be used. As a material of the opposing element electrodes 2 and 3, a general conductor material can be used. This includes, for example, Ni, Cr, Au, Mo, W, Pt, Ti, A
metals or alloys such as l, Cu, Pd and Pd, Ag, A
a printed conductor composed of a metal such as u, RuO2, Pd-Ag, or a metal oxide and glass; In2O3-SnO2
And the like and a semiconductor conductor material such as polysilicon.

The element electrode interval L, the element electrode width W, and the shape of the conductive thin film 4 shown in FIG. 2 are appropriately designed in consideration of the form to which the element is applied. The element electrode interval L can be preferably in the range of several nm to several hundred nm,
More preferably, it can be in the range of several nm to several tens nm. The element electrode width W can be set in a range from several nm to several hundred nm in consideration of the resistance values of the element electrodes 2 and 3 and the electron emission characteristics. The film thickness d of these device electrodes 2 and 3
Can be in the range of several tens nm to several nm.
In addition, not only the configuration shown in FIG. 1 but also a configuration in which the conductive layer 4 and the opposing element electrodes 2 and 3 are laminated on the substrate 1 in this order.

As the conductive thin film 4, a fine particle film composed of fine particles is preferably used in order to obtain good electron emission characteristics. The film thickness is appropriately set in consideration of the step coverage of the device electrodes 2 and 3, the resistance value between the device electrodes 2 and 3, a forming condition described later, and the like.
It is preferably in the range of several times 0.1 nm to several hundred nm, more preferably in the range of 1 nm to 50 nm. The resistance value Rs is a value from 10 2 [Ω / □] to 10 7 [Ω / □]. Note that this resistance value R
s is the resistance R of a thin film having a thickness t, a width w, and a length “l”.
Is set to R = Rs (l / w).

The material forming the conductive thin film 4 is, for example, P
d, Pt, Ru, Ag, Au, Ti, In, Cu, C
metals such as r, Fe, Zn, Sn, Ta, W, Pd, Pd
It is appropriately selected from oxides such as O, SnO2, In2O3, PbO, and Sb2O3.

The fine particle film described here is a film in which a plurality of fine particles are aggregated, and has a fine structure in a state where the fine particles are individually dispersed or arranged, or in a state where the fine particles are adjacent to each other or overlapped (some). (Including the case where the fine particles aggregate to form an island-like structure as a whole). The particle size of these fine particles is in the range from several times 0.1 nm to several hundred nm, preferably in the range from 1 nm to 20 nm. In this embodiment, the term “fine particles” is frequently used, and the meaning will be described.

Generally, small particles are called "fine particles", and smaller ones are called "ultra fine particles". It is widely practiced to call a “cluster” smaller than “ultrafine particles” and having a few hundred atoms or less. However, the definition of each word is not strict, and varies depending on the nature of the classification. Further, “fine particles” and “ultra-fine particles” may be collectively referred to as “fine particles”, and the description of the present embodiment is in line with this.

For example, "Experimental Physics Course 14 Surface / Particles" (edited by Yoshio Kinoshita, published on September 1, 1986 by Kyoritsu Shuppan) is described as follows. "When we say fine particles in this paper, the diameter is about 2-3 μm to 1
It is assumed to be up to about 0 nm, and particularly when it is referred to as ultrafine particles, it means that the particle size is from about 10 nm to about 2 to 3 nm. Sometimes both are simply written as particles,
It is by no means strict, but a rough guide. When the number of atoms constituting a particle is two to several tens to several hundreds, it is called a cluster. (Pp. 195, pp. 22-26)
(Supplement) In addition, the definition of “ultrafine particles” in the “Hayashi / Ultrafine Particle Project” of the New Technology Development Corporation has a lower minimum particle size, as follows.

In the "Ultra Fine Particle Project" of the Creative Science and Technology Promotion System (1981 to 1986), a particle having a size (diameter) in the range of about 1 to 100 nm is called "ultra fine particle". Thus, one ultrafine particle is an aggregate of about 100 to 108 atoms. The ultrafine particles are large or giant particles on an atomic scale. " -Creative Science Technology- "Hayashi Tax, Ryoji Ueda, Akira Tazaki, Mita Publishing 1
1988, page 2, lines 1 to 4) "A particle smaller than an ultrafine particle, that is, a single particle composed of several to several hundred atoms, is usually called a cluster." ~ 13 lines).

[0030] Based on the general notation as described above,
In the present embodiment, “fine particles” refers to an aggregate of a large number of atoms and molecules, and the lower limit of the particle diameter is several times 0.1 nm to about 1 nm, and the upper limit is about several nm.

The electron-emitting portion 5 is constituted by a high-resistance crack formed in a part of the conductive thin film 4 and depends on the thickness, film quality, material, and a method such as energization forming described later of the conductive thin film 4. It will be. In some cases, conductive fine particles having a particle diameter in the range of several times 0.1 nm to several tens nm are present inside the electron emission portion 5. The conductive fine particles
Some or all of the elements of the material constituting the conductive thin film 4 are contained. The electron emitting portion 5 and the conductive thin film 4 in the vicinity thereof can also contain carbon and a carbon compound.

In this embodiment, first, as shown in FIG. 1, the substrate 1 is sufficiently washed with a detergent, pure water, an organic solvent or the like, and the device electrodes 2 and 3 are formed by a vacuum evaporation method, a sputtering method or the like. After the material is deposited, the device electrodes 2 and 3 are formed on the substrate 1 by using, for example, a photolithography technique (FIG. 1A).

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

Next, energization forming is performed. As an example of the method of the forming step, the device electrode 2
By applying a pulse voltage as shown in FIG. 7 or FIG. 8 in an atmosphere for promoting reduction or aggregation, which will be described later, using a power source (not shown), the structure of the conductive thin film 4 is changed. An electron emitting portion 5 is formed (FIG. 1C). By such an energization forming process, a portion of the conductive thin film 4 whose structure is locally changed, such as destruction, deformation or alteration, is formed. These portions constitute the electron emission section 5.

The voltage waveform applied in the energization forming is preferably a pulse waveform as described later. or,
The application may be performed while increasing the pulse peak value. For example, a voltage increase of about 0.1 V was performed for each pulse.

Next, it is preferable to perform a process called an activation process on the device after the energization forming. The activation step is a step in which the element current If and the emission current Ie are significantly changed by this step. In this activation step, for example, under an atmosphere containing a gas of an organic substance,
Similar to the energization forming, it can be performed by repeating the application of the pulse. This atmosphere can be formed by using an organic gas remaining in the atmosphere when the inside of the vacuum vessel is evacuated using, for example, an oil diffusion pump or a rotary pump, or once sufficiently by an ion pump or the like. It can also be obtained by introducing a gas of an appropriate organic substance into the evacuated vacuum. At this time, the preferable gas pressure of the organic substance is the above-mentioned application form, the shape of the vacuum vessel,
Since it differs depending on the type of the organic substance, it is appropriately set according to the case. Suitable organic substances in this case include alkanes, alkenes, aliphatic hydrocarbons of alkynes, aromatic hydrocarbons, alcohols, aldehydes, ketones,
Examples thereof include organic acids such as amines, phenol, carboxylic acid, and sulfonic acid. Specific examples thereof include a saturated hydrocarbon represented by CnH2n + 2 such as methane, ethane, and propane; and a composition such as CnH2n such as ethylene and propylene. Unsaturated hydrocarbon represented by the formula, benzene, toluene, methanol, ethanol, formaldehyde, acetaldehyde, acetone, methyl ethyl ketone, methylamine, ethylamine, phenol, formic acid, acetic acid, propionic acid, and the like, or a mixture thereof can be used. By this treatment, carbon or a carbon compound is deposited on the device from the organic substance existing in the atmosphere, and the device current If, the emission current Ie
Changes significantly.

The end of the activation step is determined as appropriate while measuring the device current If and the emission current Ie. Note that the pulse width, pulse interval, pulse crest value, and the like applied in the activation step are appropriately set.

Next, it is preferable to further perform a stabilizing step on the electron-emitting device obtained through the above-described steps. This stabilization step is a step of exhausting organic substances in the vacuum vessel. It is preferable to use a vacuum exhaust device that does not use oil so that the oil generated from the device does not affect the characteristics of the element. Specifically, a vacuum exhaust device such as a sorption pump and an ion pump can be used.

In the activation step, when an oil diffusion pump or a rotary pump is used as an exhaust device and an organic gas derived from an oil component generated from the pump is used, it is necessary to keep the partial pressure of this component as low as possible. is there. The partial pressure of the organic component in the vacuum vessel is preferably 1.3 × 10 −6 power [Pa] or less, and more preferably 1.3 × 10 −6 [Pa]. Is particularly preferably equal to or lower than the −8 power [Pa]. When evacuating the vacuum vessel further,
It is preferable that the entire vacuum vessel is heated so that the organic substance molecules adsorbed on the inner wall of the vacuum vessel and the electron-emitting device are easily exhausted. The heating condition at this time is preferably from 80 ° C. to 250 ° C., and more preferably 150 ° C. or more, and it is desirable to perform the treatment for as long as possible. This is performed based on conditions appropriately selected according to various conditions such as. The pressure in the vacuum vessel needs to be as low as possible, and 1 × 10 −5 [Pa]
The following is preferable, and further, 1.3 × 10 −6 power [Pa]
The following are particularly preferred.

The atmosphere at the time of driving after performing this stabilization step is preferably the same as the atmosphere at the end of the stabilization process, but is not limited to this. If the organic substance is sufficiently removed, Even if the degree of vacuum is slightly reduced, sufficiently stable characteristics can be maintained.

By employing such a vacuum atmosphere, the deposition of new carbon or a carbon compound can be suppressed, and H 2 O, O 2, etc. adsorbed on a vacuum vessel or a substrate can be removed. As a result, the element current If and the emission current Ie are stabilized.

The basic characteristics of the electron-emitting device according to the present embodiment obtained through the above-described steps will be described with reference to the drawings.

FIG. 9 is a schematic view showing an example of the vacuum processing apparatus according to the present embodiment, and this vacuum processing apparatus also has a function as a measurement evaluation apparatus. In FIG. 9 as well, the same parts as those in FIG. 1 are denoted by the same reference numerals, and their description is omitted.

In FIG. 9, reference numeral 55 denotes a vacuum vessel,
Reference numeral 6 denotes an exhaust pump. An electron-emitting device is provided in the vacuum vessel 55. That is, 1 is a substrate (substrate) on which an electron-emitting device is provided, 2 and 3 are device electrodes, 4 is a conductive thin film, and 5 is an electron-emitting portion. 51 is a power supply for applying a device voltage Vf to the electron-emitting device, 50 is an ammeter for measuring a device current If flowing through the conductive thin film 4 between the device electrodes 2 and 3, and 54 is an electron-emitting portion of the device. 5 is an anode electrode for capturing the emission current Ie emitted from 5. Reference numeral 53 denotes a high-voltage power supply for applying a voltage to the anode electrode 54, and reference numeral 52 denotes an ammeter for measuring an emission current Ie emitted from the electron emission section 5 of the device. As an example,
The voltage of the anode electrode is in the range of 1 kV to 10 kV, and the distance H between the anode electrode and the electron-emitting device is 2 mm to 8 mm.
Can be measured as the range of

In the vacuum vessel 55, equipment necessary for measurement in a vacuum atmosphere such as a vacuum gauge (not shown) is provided.
The measurement and evaluation can be performed in a desired vacuum atmosphere. The exhaust pump 56 includes a normal high vacuum device including a turbo pump and a rotary pump, and an ultra-high vacuum device including an ion pump and the like. The entire vacuum processing apparatus provided with the electron source substrate 1 shown here can be heated by a heater (not shown). Therefore, by using this vacuum processing apparatus, the steps after the energization forming described above can also be performed.

FIG. 10 shows the emission current Ie, the device current If, and the device voltage V measured using the vacuum processing apparatus shown in FIG.
FIG. 4 is a diagram schematically showing the relationship of f. In FIG.
Since the emission current Ie is significantly smaller than the device current If, it is shown in arbitrary units. Note that both the vertical and horizontal axes are linear scales.

As is clear from FIG. 10, the surface conduction electron-emitting device according to the present embodiment has three characteristic properties with respect to the emission current Ie. That is, this element has a certain voltage (called a threshold voltage, V in FIG. 10).
When an element voltage equal to or higher than th) is applied, the emission current Ie sharply increases. On the other hand, when the element voltage is equal to or lower than the threshold voltage Vth, the emission current Ie is hardly detected. That is, it is a non-linear element having a clear threshold voltage Vth with respect to the emission current Ie. Since the emission current Ie depends monotonically on the device voltage Vf, the emission current Ie can be controlled by the device voltage Vf. The emission charge captured by the anode electrode 54 depends on the time during which the device voltage Vf is applied. That is, the amount of charge captured by the anode electrode 54 can be controlled by the time during which the device voltage Vf is applied.

Next, another embodiment of the present invention will be described.

FIG. 3 is a schematic cross-sectional view of an element for explaining another example of the method of manufacturing the electron source according to the present embodiment. FIG. 4 is a surface conduction type emission manufactured by the manufacturing method according to the present embodiment. It is a top view of an element showing other examples of an element.

FIGS. 5 and 6 are schematic views showing an example in which a large number of surface conduction electron-emitting devices manufactured by the method of manufacturing an electron source according to the present embodiment are arranged. In these figures, common parts are denoted by the same reference numerals, and description thereof is omitted.

In FIG. 3, reference numeral 6 denotes a droplet applying device, and reference numeral 7 denotes a droplet. 5 and 6, reference numeral 10 denotes a surface conduction electron-emitting device, 11 denotes an X-direction wiring, 12 denotes a Y-direction wiring,
3 is a wiring, and 14 is a connection.

In FIG. 3, first, device electrodes 2 and 3 are formed on a substrate 1 at a distance of L in the same manner as described above (FIG. 3A). Next, a droplet 7 made of a solution containing a metal element is ejected from a droplet applying device (for example, an ink jet recording device) 6 (FIG. 3B), and the conductive thin film 4 is brought into contact with the device electrodes 2 and 3. (Fig. 3
(C)).

Next, a crack is generated in the conductive thin film 4 by a forming process described later in a reducing atmosphere to form the electron emission portion 5 (FIG. 3D).

To give a specific example of the droplet applying device 6,
Any device may be used as long as it can form an arbitrary droplet.
Can be controlled in the range of about
It is preferable to use an ink-jet type apparatus which can easily form a small amount of droplets of a few tens to tens of ng.

Examples of such an ink jet system include an ink jet system using a piezoelectric element or the like, and an ink jet system using a method in which bubbles are formed in a liquid by thermal energy and the liquid is discharged as droplets. Can be

Next, an embodiment of an electron source in which a large number of the above-described surface conduction electron-emitting devices are arranged on a substrate will be described.

In FIG. 5, an electron source is formed by arranging a large number of the above-mentioned surface conduction electron-emitting devices in a ladder shape and arranging a plurality of line-shaped electron sources connected by wiring. The wiring 13 has m wirings Dx1, Dx2,..., Dxm, and is formed on the substrate 1 by a vacuum deposition method, a printing method, a sputtering method, or the like. These wirings are made of a conductive metal or the like having a desired pattern, and the material, film thickness,
The wiring width is set.

FIG. 6 is a plan view of an electron source formed by arranging a large number of the above-described surface conduction electron-emitting devices 10 in a matrix.

Here, the X-directional wiring 11 is composed of m X-directional wirings (row wirings) Dx1, Dx2,..., Dxm, and the Y-directional column wirings 12 are n Y-directional wirings (column wirings) Dy1,. Dy2,
, Dyn, which are formed on the substrate 1 by a vacuum deposition method, a printing method, a sputtering method, or the like. These wirings are made of a conductive metal or the like having a desired pattern, and are electrically connected to each surface conduction type emission element by a connection 14 made of a conductive metal or the like formed by a vacuum deposition method, a printing method, a sputtering method, or the like. The material, film thickness, and wiring width are set so that a substantially uniform voltage is supplied to the plurality of surface conduction electron-emitting devices.

An interlayer insulating layer (not shown) is provided between the m X-directional wirings 11 and the n Y-directional wirings 12 to electrically separate (insulate) them. (Where m and n are both positive integers). These interlayer insulating layers (not shown) are made of SiO2 or the like formed by a vacuum deposition method, a printing method, a sputtering method, or the like. For example, this interlayer insulating layer is formed in a desired shape on the entire surface or a part of the substrate 1 on which the X-directional wiring 11 is formed, and particularly, can withstand a potential difference at an intersection of the X-directional wiring 11 and the Y-directional wiring 12. As described above, the film thickness, material, manufacturing method, and the like are appropriately set. Further, the X-direction wiring 11 and the Y-direction wiring 12 are led out as external terminals.

Next, at the time of manufacturing such an electron source, energization forming is performed on each of the conductive thin films 4 formed at positions where a large number of the surface conduction electron-emitting devices 10 will be formed. As an example of the method of the energization forming step, a case in which energization forming processing is performed on a ladder-shaped line electron source as shown in FIG. 5 will be described.

The individual resistance of the conductive thin film 4 arranged in advance as a line electron source is measured, and the minimum value (Rmin) of each resistance is measured.
And the maximum value (Rmax). 7 or 8 using a power source (not shown) between Dx1 and Dx2 of the wiring 13 (between Dx (odd number) and Dx (even number) of the wiring 13) in an atmosphere that promotes reduction or aggregation. As shown, the resistance is at a minimum (R
min), a voltage (Vmin) for forming the electron-emitting portion 5 is applied to the conductive thin film 4. Thereafter, from the voltage (Vmin) for forming the electron emitting portion 5 on the conductive thin film 4 having the minimum resistance (Rmin) to the voltage (Vmin) for forming the electron emitting portion 5 of the conductive thin film 4 having the maximum value (Rmax). Vmax) ｛= Vmin√
By applying a pulse voltage up to (Rmax / Rmin)｝, equivalent power is supplied to the conductive thin film 4 having the minimum resistance (Rmin) and the maximum resistance (Rmax). As a result, an electron emitting portion 5 having a changed structure is formed in each conductive thin film 4.

When forming an electron source having the structure shown in FIG. 6, a forming process is performed on each of the conductive thin films (portions serving as electron-emitting devices) arranged in a matrix.

As a method of applying a voltage in the energization forming process in the wiring of FIG.
And the X-direction wiring 11 and all the Y-direction wirings 12 are selected.
A voltage is applied between them. Alternatively, an arbitrary Y-direction wiring 12 is selected, and a voltage is applied between this Y-direction wiring 12 and all the X-direction wirings 11. Alternatively, all the X-direction wirings 11 and Y
There is a method of applying a voltage between the directional wirings 12, and the like, which is appropriately selected based on the number of surface conduction type emission elements to be finally formed, power consumption during forming processing, and the like.

As shown in FIG. 7 or FIG. 8, the electron emitting portion is formed on a conductive thin film having a minimum element resistance (Rmin) in an atmosphere for promoting reduction or aggregation by using a power supply (not shown). After the voltage (Vmin) to be formed is applied, the resistance is changed from the voltage (Vmin) for forming the electron emitting portion 5 to the conductive thin film 4 having the minimum value (Rmin) to the conductive thin film 4 having the maximum value (Rmax). Voltage (Vmax) ｛= Vm for forming electron emission portion 5
By applying a pulse voltage up to in {(Rmax / Rmin)}, an electron emitting portion 5 having a changed structure is formed in each conductive thin film 4.

Next, the waveform of the voltage (Vform) applied during the energization forming will be described with reference to FIGS.

In the figure, each of T1 and T2 is
The pulse width and pulse interval of the forming voltage are shown. Usually, the pulse width T1 is set in the range of 1 μsec to 10 msec, and the pulse interval T2 is set in the range of 10 μsec to several seconds. The peak value (peak voltage during energization forming) of the triangular wave in FIG. 7 and the rectangular wave in FIG. 8 is, for example, 0.1 V for each pulse application.
Can be increased by degrees.

Also, a constant forming voltage (Vform)
Is applied, the forming voltage is sequentially increased from 0 V, and a voltage at which the resistance of the conductive thin film 4 changes from a linear change to a non-linear change may be set.

When the conductive film 4 is made of a metal oxide, a reducing substance can be used as an atmosphere gas for promoting the reduction or aggregation of the conductive film 4. In addition to CO and the like, gases of organic substances such as methane, ethane, ethylene, propylene, benzene, toluene, methanol, ethanol, and acetone are also effective. This is presumably because when the material constituting the conductive film changes from metal oxide to metal by reduction, aggregation occurs with the metal. On the other hand, when the conductive film 4 is made of a metal, CO and acetone do not show the effect of promoting the aggregation because the aggregation due to the reduction does not occur, but H2 has the effect of promoting the aggregation even in this case. There is.

FIG. 11 is a flowchart showing a method for manufacturing an electron source according to the present embodiment.

First, in step S1, after cleaning the substrate 1, the device electrodes 2 and 3 and the row and column wiring for wiring the device electrodes 2 and 3 in, for example, a ladder shape or a matrix shape on the substrate 1. Is arranged. Next, proceed to step S2,
The conductive thin film 4 is formed between the pairs of the device electrodes 2 and 3 at positions corresponding to the respective positions of the plurality of surface conduction electron-emitting devices arranged in a matrix using, for example, an inkjet method. Next, the process proceeds to step S3, where the resistance of each conductive thin film 4 thus formed is measured. In step S4, the minimum value (Rmin) and the maximum value (Rmax) of the resistance values are obtained based on the measured resistance values, and the minimum applied forming voltage (Vmin) is determined based on the resistance values.
And the maximum applied forming voltage {Vmax = Vmin} (Rmax
/ Rmin)｝. Next, the substrate 1 is placed in a vacuum container 55.
And the inside of the container 55 is evacuated to approximate a vacuum state. In this case, the vacuum vessel 5 contains an atmosphere gas that promotes the reduction or aggregation of the conductive film 4 as described above.

Then, in steps S6 to S9, energization forming is executed. Here, the minimum forming voltage (Vmin) is first applied, and then, in step S7, the resistance of the conductive thin film 4 is measured to grasp the progress of the forming. In step S8, the maximum forming voltage (Vma
It is checked whether the voltage has increased to x). If not, the process proceeds to step S9, and the forming voltage is increased by 0.1 [V]. Note that the application of the forming voltage is performed, for example, when the conductive thin films 4 are arranged in a matrix.
One row wiring is selected, a forming voltage is applied to each conductive thin film 4 connected to the selected row wiring, and this process is performed on all the row wirings.

When the forming process is completed, the process proceeds to step S10, and the above-described activation process is executed.
Here, for example, in an atmosphere containing a gas of an organic substance, the application is performed by repeating the application of a pulse voltage as in the above-described energization forming. Then, the process proceeds to step S11, in which a stabilizing step of exhausting the organic substance in the vacuum vessel 55 is performed.

The method of manufacturing the electron source according to the present embodiment has been described above. Next, a specific example of the process of the present embodiment will be described.

(Embodiment 1) An electron source according to Embodiment 1 is the same as that shown in FIG. Further, FIG.
FIG. 2 is a plan view of a surface conduction electron-emitting device of the electron source manufactured according to the first embodiment. FIG. 5 is a plan view of the electron source manufactured according to the first embodiment. FIG. 7 is a diagram showing a forming voltage waveform according to the first embodiment. 1, 2 and 5 denote the same members.

Hereinafter, a method of manufacturing the surface conduction electron-emitting device according to the first embodiment will be described in detail.

In FIGS. 1, 2 and 5, 1 is a substrate,
Reference numerals 2 and 3 denote device electrodes, 4 denotes a conductive thin film, 5 denotes an electron-emitting portion, 10 denotes a surface-conduction-type emission device, and 13 denotes a wiring.

Here, an element was formed on a substrate by photolithography in the following procedure.

(1) A quartz substrate is used as the substrate 1, which is sufficiently washed with an organic solvent, and then the device electrode 2 made of Ni is formed on the substrate 1 by a general vacuum film forming technique and photolithography technique. 3 (FIG. 1)
(A)). At this time, the interval L between the device electrodes was 10 μm, the width W was 600 μm, and the thickness was 100 nm.

(2) Next, an organic palladium-containing solution (ccp-4230, manufactured by Okuno Pharmaceutical Co., Ltd.) was spin-coated, and the width W ′ was 300 μm by photolithography.
m. Next, a heat treatment was performed at 300 ° C. for 10 minutes to form a fine particle film made of palladium oxide (PdO) fine particles, thereby forming a conductive thin film 4 (FIG. 1B). Note that the fine particle film described here is a film in which a plurality of fine particles are aggregated as described above, 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 overlap each other. (Island-shaped) film.

(3) Next, Al is formed on the device electrodes 2 and 3 by a general vacuum film forming technique and photolithography technique.
A wiring 13 made of (aluminum) was formed (FIG. 5). At this time, the thickness of the wiring was 10 μm.

(4) Next, when the resistance of each of the plurality of conductive thin films 4 manufactured as described above was measured, the minimum value (Rmin) was 1020Ω and the maximum value (Rmax) was 15
It was 10Ω. (5) Next, after evacuating to 1 × 10 −3 [Pa] or less, a triangular wave having a pulse width T1 of 1 ms, a pulse interval T2 of 10 ms, and a peak value of 4 V is applied between the wirings 13. Voltage (V
min), a mixed gas of N2 (98%)-H2 (2%) is introduced, and the voltage Vmax ｛= Vmin√ (Rmax / Rmi) while increasing by 0.1 V step for each pulse application.
n) The electron emitting portion 5 was formed by applying an electric current to the conductive thin film 4 by applying a voltage of up to 4.9 V, which is｝.

According to the above-described manufacturing method, an electron source including a large number of surface conduction electron-emitting devices was manufactured. Then, when the characteristics of the electron source were measured by the measuring device shown in FIG. 9, in all the surface conduction electron-emitting devices, a plurality of surface conduction electron-emitting devices having good characteristics without variation in device characteristics were obtained. Electron source was obtained. It is considered that even if the resistance of each of the conductive thin films fluctuated, the forming could be performed without any overload during the forming process.

(Embodiment 2) An electron source according to Embodiment 2 is the same as that shown in FIG. Further, FIG.
FIG. 3 is a plan view of a surface conduction electron-emitting device of an electron source manufactured according to the second embodiment. FIG. 6 is a plan view of the electron source manufactured according to the second embodiment. FIG. 8 is a diagram illustrating a forming voltage waveform according to the second embodiment. 3, 4 and 6 denote the same members.

Hereinafter, a method of manufacturing the surface conduction electron-emitting device according to the second embodiment will be described in detail.

In FIGS. 3, 4 and 6, 1 is a substrate,
2 and 3 are device electrodes, 4 is a conductive thin film, 5 is an electron emitting portion, 6 is a droplet applying device, 7 is a droplet, 10 is a surface conduction type emitting device, 11 is an X-direction wiring, and 12 is a Y-direction wiring. , 14 are connections.

A method of manufacturing the surface conduction electron-emitting device according to the second embodiment will be described in detail.

(1) A quartz substrate is used as the substrate 1, and after thoroughly cleaning the substrate with an organic solvent, the device electrode 2 made of Ni is formed on the substrate 1 by a general vacuum film forming technique and photolithography technique. And 3 were formed. The distance L between the device electrodes is 10 μm, the width W is 600 μm, and the thickness is 10 μm.
It was set to 0 nm. 5 nm thick Cr and 600 nm thick A
The X-direction wiring 11 of Au / Cr made of u was formed.
Next, an interlayer insulating film made of SiO2 having a thickness of 1 μm was formed at a portion where the X-directional wiring 11 and the Y-directional wiring 12 intersect.
Next, an Au / Cr Y-direction wiring 12 composed of 5 nm thick Cr and 600 nm thick Au was formed.

(2) Next, using an inkjet ejecting device as the droplet applying device 6 and using a 0.1 wt% aqueous solution of acetic acid Pd as a solution for forming the conductive thin film 4, a droplet is applied between the device electrodes 2 and 3. 7 and applied.

(3) Next, a heat treatment was performed at 350 ° C. for 10 minutes to form a fine particle film composed of fine particles of palladium oxide (PdO).

(4) Next, when the resistance of each of the plurality of conductive thin films prepared as described above was measured, the minimum value (Rmin) was 815Ω and the maximum value of the resistance (Rmax) was 1
624Ω.

(5) After evacuating to a vacuum of 1 × 10 −3 [Pa] or less, a pulse width T1 of 1 ms and a pulse interval T2 of 10 m are applied between the X-directional wiring 11 and the Y-directional wiring 12. A voltage (Vform) having a peak value of 3.8 V as a rectangular wave of seconds is applied, a mixed gas of N2 (98%)-H2 (2%) is introduced, and the voltage Vmax is increased in steps of 0.1 V.
The voltage was applied up to 5.4 V where {= Vmin {(Rmax / Rmin)}. In this way, each electron emitting portion 5 was formed by conducting forming process of the conductive thin film 4.

An electron source composed of a large number of surface conduction electron-emitting devices was manufactured by the above-described manufacturing method, and the characteristics were measured with the measuring device shown in FIG. An electron source composed of a plurality of surface conduction electron-emitting devices having good characteristics without variation was obtained. This means that even if the resistance of each conductive thin film varies,
It is considered that the forming was surely performed without being overloaded during the forming process.

(Application Example 1) FIG. 12 is a schematic perspective view of a display panel showing an application example of an image forming apparatus using an electron source manufactured in Embodiment 2 of the present invention. It is shown in a partially broken state.

In FIG. 12, reference numeral 81 denotes an electron source substrate;
Is a wiring in the X direction (row), 83 is a wiring in the Y direction (column), and 84 is a surface conduction electron-emitting device. Reference numeral 91 denotes a rear plate on which the electron source substrate 81 is fixed, 96 denotes a face plate in which a fluorescent film 94 and a metal back 95 are formed on an inner surface of a glass substrate 93, and 92 denotes a support frame. Is configured. Reference numeral 102 denotes a terminal outside the container of the X-direction wiring 82, and reference numeral 103 denotes a terminal outside the container of the Y-direction wiring 83.

An image forming apparatus using the display panel thus manufactured was prepared, and a television display was performed based on an NTSC television signal. As a result, good performance without any problem was shown.

(Application 2) FIG. 13 is an external perspective view of a display panel in which the surface conduction electron-emitting devices manufactured in the first embodiment of the present invention are arranged in a ladder shape, and a part thereof is shown to show the internal structure thereof. Is shown in a broken state. In this figure, parts common to FIG. 12 are denoted by the same reference numerals.

In the figure, 100 is a grid electrode, 10
Reference numeral 1 denotes a hole, 104 denotes a terminal outside the container for X-direction wiring, and 105 denotes a terminal outside the container of the grid electrode 100.

An image forming apparatus using the display panel thus manufactured was prepared, and a television display was performed based on an NTSC television signal. As a result, good performance without any problem was shown.

As described above, according to the present embodiment, the minimum value (Rmin) of each resistance value of the conductive thin film
After applying a voltage (Vmin) for forming an electron-emitting portion to the conductive thin film of the minimum value (Rmin) according to the maximum value (Rmax) and the maximum resistance value from the voltage (Vmin) for the minimum resistance value (Rmin) (Vmax) applied to the conductive thin film of (Rmax)
By conducting the energization forming process while continuously increasing to {= Vmin {(Rmax / Rmin)}, an electron source with uniform element characteristics is manufactured even if the resistance of the conductive thin film varies. be able to.

[0101]

As described above, according to the present invention, there is an effect that variations in device characteristics of a plurality of electron-emitting devices can be reduced.

Further, according to the present invention, it is possible to suppress variations in element characteristics of the electron source due to variations in resistance of the conductive film.

Further, according to the present invention, it is possible to prevent the conductive film from being reduced or agglomerated before the voltage necessary for forming the electron-emitting portion is applied to the conductive film during forming. This has the effect.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view illustrating an example of a method for manufacturing an electron source according to an embodiment of the present invention.

FIG. 2 is a schematic plan view illustrating an example of a method for manufacturing an electron source according to an embodiment of the present invention.

FIG. 3 is a schematic sectional view illustrating an example of a method for manufacturing an electron source according to another embodiment of the present invention.

FIG. 4 is a schematic plan view illustrating an example of a method for manufacturing an electron source according to another embodiment of the present invention.

FIG. 5 is a schematic diagram showing an example of an electron source in which surface-conduction emission devices are wired in a ladder shape according to an embodiment of the present invention.

FIG. 6 is a schematic diagram illustrating an example of an electron source in which surface conduction electron-emitting devices are arranged in a matrix according to an embodiment of the present invention.

FIG. 7 is a diagram showing an example of a forming voltage waveform used for manufacturing the electron source according to the embodiment of the present invention.

FIG. 8 is a diagram showing another example of a forming voltage waveform used for manufacturing the electron source according to the embodiment of the present invention.

FIG. 9 is a schematic configuration diagram of a measurement evaluation device for measuring electron emission characteristics of the surface conduction electron-emitting device according to the embodiment of the present invention.

FIG. 10 shows device current, emission current-device voltage characteristics (IV characteristics) of a surface conduction electron-emitting device according to an embodiment of the present invention.
FIG.

FIG. 11 is a flowchart showing a manufacturing process of the electron source according to the embodiment of the present invention.

FIG. 12 is a partially cutaway perspective view of a display panel using an electron source in which surface conduction electron-emitting devices are arranged in a matrix according to an embodiment of the present invention.

FIG. 13 is a partially cutaway perspective view of a display panel using an electron source in which surface conduction emission devices are wired in a ladder shape according to an embodiment of the present invention.

FIG. 14 is a diagram showing an example of a conventional surface conduction electron-emitting device.

Claims (18)

[Claims] 1. A method for manufacturing an electron source, comprising a plurality of electron-emitting devices each having a conductive film having an electron-emitting portion between electrodes disposed on a substrate, wherein a resistance of each of the conductive films is detected. A minimum voltage (Vm) to be applied according to the minimum value (Rmin) and the maximum value (Rmax) of the resistance value detected in the detection step.
in) and a voltage determining step of determining a maximum voltage (Vmax); and continuously increasing the voltage from the minimum voltage to apply a voltage to each of the conductive films, thereby forming an electron emission portion on the conductive film. A forming step of forming the electron source. 2. The method according to claim 1, wherein in the voltage determining step, the maximum voltage (Vmax) is obtained by Vmin√ (Rmax / Rmin). 3. The method according to claim 1, wherein in the forming step, an applied voltage is increased by a predetermined amount from the minimum voltage and applied up to the maximum voltage. 4. The method of manufacturing an electron source according to claim 1, wherein the voltage applied in the forming step is a triangular or rectangular wave pulse voltage. 5. The method according to claim 1, wherein the forming step is performed by housing the substrate in an atmosphere that promotes reduction or aggregation of the conductive film. Manufacturing method of electron source. 6. The method according to claim 1, further comprising an activation step of applying a predetermined voltage to each of said electron-emitting devices after said forming step.
Item 14. The method for producing an electron source according to Item 1. 7. The method according to claim 6, further comprising, after the activation step, a stabilization step of further evacuating the inside of the container accommodating the substrate. 8. The method for manufacturing an electron source according to claim 1, wherein said electron-emitting devices are connected in a ladder shape. 9. The method according to claim 1, wherein the electron-emitting devices are connected in a matrix. 10. An apparatus for manufacturing an electron source, wherein a plurality of electron-emitting devices each having a conductive film having an electron-emitting portion between electrodes are arranged on a substrate, wherein the conductive material is arranged on the substrate. Detecting means for detecting the resistance of each of the conductive films, and a minimum value (Rmi) of the resistance value detected by the detecting means.
n) and voltage determining means for determining a minimum voltage (Vmin) and a maximum voltage (Vmax) to be applied according to the maximum value (Rmax); and And a forming means for applying a voltage to each of the conductive films by increasing a voltage to form an electron emission portion in the conductive film. 11. The apparatus according to claim 10, wherein the voltage determination means obtains the maximum voltage (Vmax) by Vmin√ (Rmax / Rmin). 12. The apparatus according to claim 10, wherein the forming unit increases the applied voltage from the minimum voltage by a predetermined amount and applies the voltage to the maximum voltage. 13. The apparatus according to claim 10, wherein the forming unit applies a triangular wave or a rectangular wave pulse voltage. 14. The forming method according to claim 10, wherein the forming unit executes the forming by housing the substrate in an atmosphere that promotes reduction or aggregation of the conductive film. An apparatus for manufacturing an electron source according to claim 1. 15. The semiconductor device according to claim 1, further comprising an activating means for applying a predetermined voltage to each of said electron-emitting devices after the forming by said forming means.
15. The apparatus for manufacturing an electron source according to any one of 0 to 14. 16. The electron source according to claim 15, further comprising a stabilizing means for further evacuating the inside of the container accommodating the substrate after the activation processing by the activating means. manufacturing device. 17. The apparatus according to claim 10, wherein the electron-emitting devices are connected in a ladder shape. 18. The apparatus according to claim 10, wherein the electron-emitting devices are connected in a matrix.