JP2000251788A - Image display device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image display device having a small change over aging (deterioration over aging) of brightness and a small occurrence frequency of brightness irregularities over aging in an image display region. SOLUTION: In this image display device having an electron source substrate where an electron source for emitting electrons corresponding to an image signal is formed, and a face plate where a phosphor film for emitting light by receiving the electrons is formed, a nonvolatile getter layer is formed by getter materials 9 composed of particles having diameters in the range of 1 μm or more and 10 μm or less on the whole surface of the electron source substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus and a method of manufacturing the same, and more particularly to an image forming apparatus and an electron source substrate having an electron source that emits electrons in response to a signal, from a particle having a diameter of 1 μm or more and 10 μm or less. The present invention relates to an image forming apparatus having a non-evaporable getter layer formed thereon and a method of manufacturing the same.

[0002]

2. Description of the Related Art In a device for irradiating an electron beam emitted from an electron source to a phosphor as an image display member and causing the phosphor to emit light to display an image, a vacuum container containing the electron source and the image forming member is used. Must be kept in a high vacuum. That is, when gas is generated inside the vacuum vessel and the pressure rises, the degree of the effect depends on the type of gas, but it adversely affects the electron source and reduces the amount of electron emission,
This is because a bright image cannot be displayed. Further, the generated gas is ionized by the electron beam to become ions, which are accelerated by an electric field for accelerating the electrons and collide with the electron source, which may damage the electron source. Further, in some cases, a discharge may be generated inside, and in this case, the device may be destroyed.

Normally, a vacuum container of an image display device is formed by combining glass members and bonding a bonding portion with frit glass or the like. Once the bonding is completed, the pressure is maintained in the vacuum container. Done by a getter.

In an ordinary CRT, an alloy containing Ba as a main component is heated in a vacuum vessel by energization or high frequency.
A vapor-deposited film is formed on the inner wall of the container, thereby adsorbing gas generated inside to maintain a high vacuum.

On the other hand, a flat display using an electron source in which a large number of electron-emitting devices are arranged on a flat substrate has been developed. In this case, the volume of a vacuum vessel is smaller than that of a CRT. However, the area of the wall surface from which the gas is released does not decrease, and the pressure inside the container increases when the same amount of gas is generated. In the case of a CRT, the wall surface without an electron source or an image display member is sufficiently provided inside the vacuum container, and the above-mentioned getter material can be deposited on this portion. An electron source and an image forming member occupy much of the inner surface area. If the above-mentioned vapor-deposited getter film adheres to this portion, adverse effects such as short-circuiting of the wiring occur, so that the place where the getter film can be formed is limited. For this reason, it is conceivable to use a corner of the vacuum container or the like for forming a getter film so that the getter material does not adhere to a portion (hereinafter, referred to as an “image display area”) formed by the image forming member and the electron source. However, when the size of the flat display is increased to some extent, it is not possible to secure a sufficient area of the getter vapor-deposited film as compared with the gas emission amount.

In order to solve this problem and to secure a sufficient getter film area, as shown in FIG.
A wire getter 26 is provided outside the image display area between the phosphor 27 and the field emission element 28 opposed to each other, for example, on the outer peripheral portion, thereby depositing the getter film 29 on the outer peripheral wall surface. Forming method (JP-A-5-1519)
No. 16).

Further, as shown in FIG. 12B, a method of attaching a getter chamber 218 having a getter material 217 for forming a getter film to the side of the space between the face plate 24 and the rear plate 22 (see FIG. 12B). JP-A-4-2896
No. 40).

Further, there is a method in which a space is provided between the electron source substrate and the rear plate of the vacuum vessel, and a getter film is formed there (Japanese Patent Laid-Open No. 1-235152). In the flat-panel image display device, the problem of the generation of gas in the vacuum vessel includes the problem that the pressure tends to increase locally, in addition to the problem described above. In an image display apparatus having an electron source and an image display member, a portion of the vacuum vessel that generates gas is an image display area mainly irradiated with an electron beam.

In the case of a conventional CRT, the image display member and the electron source are separated from each other, and a getter film formed on the inner wall of the vacuum vessel is provided between the two. , And a part is adsorbed by the getter film, and the pressure does not increase so much at the electron source. Further, since the getter film is also provided around the electron source, an extremely local pressure increase does not occur even by the gas emitted from the electron source itself. However, in the flat panel image display device, since the image display member and the electron source are close to each other, the gas generated from the image display member reaches the electron source before sufficiently diffusing, and causes a local pressure increase. Bring. In particular, in the central part of the image display area, it is not possible to diffuse to the area where the getter film is formed, and therefore it is considered that a local pressure rise is larger than that in the peripheral part. The generated gas is emitted from the electron source and is ionized by the electrons, which may cause damage between the electron source and the image display member, or may cause a discharge to destroy the electron source.

In view of such circumstances, a flat image display device having a specific structure discloses a structure in which a getter material is arranged in an image display area to immediately adsorb generated gas. Have been. For example, JP-A-4-124
No. 36 discloses a method of forming a gate electrode with a getter material in an electron source having a gate electrode for extracting an electron beam. The method includes a field emission power supply having a conical projection as a cathode, and a pn junction. The semiconductor electron source having is illustrated.

Japanese Patent Application Laid-Open No. 63-181248 discloses a flat plate having a structure in which an electrode (grid or the like) for controlling an electron beam is disposed between a cathode (cathode) group and a face plate of a vacuum vessel. On the display,
A method of forming a getter material film on the control electrode is disclosed.

No. 5,453,659 “Anod
e Plate for Flat Panel Display having Integrated G
etter ", issured 26 Sept. 1995 to Wallace et al. shows a getter member formed in a gap between stripe-shaped phosphors on an image display member (anode plate). In this example, The getter material is electrically separated from the phosphor and the conductor electrically connected to the phosphor, and the getter is activated by applying an appropriate potential to the getter and irradiating and heating the electrons emitted from the electron source. It is to make.

[0013]

SUMMARY OF THE INVENTION As already mentioned,
In a device that irradiates an electron beam emitted from an electron source onto a phosphor that is an image display member and causes the phosphor to emit light to display an image, the inside of a vacuum container that contains the electron source and the image forming member has a high vacuum. Must be kept. that is,
When gas is generated inside the vacuum vessel and the pressure rises, the degree of the effect differs depending on the type of gas, but this has a negative effect on the electron source, reduces the amount of electron emission, and makes it impossible to display a bright image. . Further, the generated gas is ionized by the electron beam to become ions, which are accelerated by an electric field for accelerating the electrons and collide with the electron source, which may damage the electron source. Further, in some cases, a discharge may be generated inside, and in this case, the device may be destroyed.

In the above-described image display apparatus, the one that contributes most as a gas generation source is an image display member such as a fluorescent film which is impacted by high-energy electrons. Of course, if degassing can be performed sufficiently, such as baking at a high temperature for a long time, the generation of gas can be reduced, but in an actual device, the electron-emitting device and other members are thermally damaged. In some cases, the degassing process cannot be performed, and in such a case, gas is highly likely to be generated. This gas adsorbs on the electron emission portion of the electron source and affects the characteristics.In addition, gas molecules ionized by the electrons emitted from the electron source form a gap between the image display member and the electron source or between the image display member and the positive electrode of the electron source. Accelerated by the electric field formed by the voltage applied between the negative electrodes,
There is a possibility that the positive electrode or the negative electrode of the electron source may be damaged by colliding.

Further, when the pressure of the gas is locally and instantaneously increased, ions accelerated by the electric field may collide with another gas molecule and generate ions one after another, thereby causing a discharge. There is. In this case, the electron source may be partially destroyed, causing deterioration of the electron emission characteristics.
The generation of gas from the image display member emits electrons after the image display device is formed, thereby causing the phosphor to emit light,
H2O, H2, CH4, CO, C contained in phosphor
Gases such as O2 and O2 are rapidly released. This may cause phenomena such as a noticeable decrease in image brightness at the beginning of driving.

When a getter region is provided outside the display region as in the prior art, the gas generated near the center of the image display region takes a long time to reach the outer getter region. When it is not possible to exert sufficient effects to prevent the electron emission characteristics from deteriorating by being re-adsorbed to the electron source before being adsorbed to the electron source, especially when the brightness of the image is conspicuous in the center of the image display area. There is. Therefore, in a flat plate image display device having no gate electrode or control electrode as described above, a device having a novel structure in which a getter member can be arranged in an image display region so that generated gas can be quickly removed. Was required to be created.

In order to solve the above problem, a method of forming a getter material on an anode plate is disclosed in US Pat.
No. 53,659, the getter material is formed using a vacuum evaporation technique such as electron beam evaporation or ion beam sputtering, and the formed getter layer is a thin film as an aggregate of fine particles. Therefore, the surface area is reduced. Due to the property of a non-evaporable getter that absorbs a gas by surface adsorption, a small surface area means that the properties (adsorption speed and total adsorption amount) of the getter deteriorate. Further, the getter formed by vacuum deposition is in an extremely active state immediately after the formation, and when it is taken out of the vacuum device, gas adsorption occurs instantaneously and deteriorates remarkably. As described above, since the getter layer formed of a thin film has a small surface area, deterioration immediately after formation is a great deal of damage, and it is difficult to obtain desired adsorption characteristics even if the getter is activated again in a subsequent step. Even if the conventional method of stabilizing the surface by nitrogen gas replacement for the purpose of protecting the non-evaporable getter is used, the surface area of the getter particles is small. Until the adsorbed gas permeates, the ability as a getter is lost.

Therefore, in the anode plate disclosed in the above-mentioned US Patent, after the getter is formed, sealing, baking, and the like, which are the subsequent steps, are performed in a vacuum atmosphere to compensate for the above-mentioned disadvantage. Therefore, it is inevitable that the apparatus and the process become complicated.

As a method of activating the getter material, the getter material itself is energized or directly irradiated with an electron beam emitted from an electron source, so that an electrical insulation between the getter and the phosphor is obtained. Since a member and a process for removing the fine particles are required, there arises a problem that a precise fine processing technique must be used.

On the other hand, as a place where a gas adsorbing material such as an evaporable or non-evaporable getter is arranged in the image display area,
In addition to the image forming member described above, it can be arranged on the substrate side (hereinafter referred to as a rear plate) on which an electron source is formed.
No. 100242, JP-A-6-3714, JP-A-8-
No. 22,785, and the like. JP-A-2-1
No. 00242, Japanese Patent Application Laid-Open No. 6-3714 discloses a method of arranging a getter layer on the surface of a grid electrode or a control electrode included in a vacuum envelope, or forming a getter material itself with a getter material. Both require other electrodes between the rear plate and the image forming member as the image forming apparatus, for example, a grid electrode, and require extremely complicated steps in manufacturing as described later, and are assumed in the present invention. Such an image forming apparatus having a simple configuration that does not include a grid electrode or the like cannot dispose these getters.

Furthermore, the non-evaporable getter described in Japanese Patent Application Laid-Open No. 6-3714 needs to fix the ribbon-shaped getter on the grid electrode by spot welding, which requires more complicated steps and high density. It is difficult to apply to the arranged electron source substrate.

Further, the getter disposing method disclosed in Japanese Patent Application Laid-Open No. H8-22785 has a complicated structure such as providing a recess on the rear plate side to increase the getter area due to the restriction of using an evaporable getter. In addition, there is a difficulty in the manufacturing process that sealing must be performed in a vacuum after the getter is formed.

As a method of arranging the non-evaporable getter on the wiring electrode on the rear plate or the like, a method suitable for fine processing such as a vacuum evaporation method is also considered as in the case of arranging on the image forming member. However, in the case of vacuum deposition, as in the case of the above-mentioned “anode plate” in which a getter is arranged on an image forming member, the getter surface area is reduced and sufficient getter characteristics cannot be obtained.

On the other hand, it is needless to say that an electron-emitting device constituting an electron source used for a flat display is simple in structure and manufacturing method from the viewpoint of production technology and manufacturing cost. If the manufacturing process is composed of thin film lamination and simple processing, or if a large product is to be manufactured, one that can be manufactured by a technique such as a printing method that does not require a vacuum device is required.

In this respect, the electron source disclosed in the above-mentioned Japanese Patent Application Laid-Open No. Hei 4-12436, in which the gate electrode is made of a getter material, requires a vacuum for manufacturing a conical cathode tip or a semiconductor junction. Complicated steps in the apparatus are required, and there is a limit to the increase in size due to the manufacturing apparatus.

Further, as disclosed in Japanese Patent Application Laid-Open No. 63-181248, an apparatus in which a control electrode or the like is provided between an electron source and a face plate has a complicated structure. A complicated process will be involved.

Next, as an electron-emitting device having a structure capable of satisfying the above-mentioned requirement that the manufacturing process is easy,
A horizontal field emission electron-emitting device and a surface conduction electron-emitting device can be given. A horizontal field emission type electron-emitting device is formed by opposing a cathode (gate) having a sharp electron-emitting portion on a flat substrate, and using a thin film deposition method such as vapor deposition, sputtering, plating, and the like, and a general photolithography method. Electrons are emitted by a lithography technique, an example of which is disclosed in JP-A-7-235255.

An electron source using these elements has a gate electrode having a shape as disclosed in JP-A-4-12436 and a control electrode as disclosed in JP-A-63-181248. Therefore, the getter cannot be arranged in the image display area by the same method as these, and the getter is arranged outside the image display area, thereby avoiding the deterioration, destruction, etc. due to the decrease in the degree of vacuum. It is difficult to do.

Accordingly, it is an object of the present invention to reduce a change in luminance over time (decrease over time) in an image forming apparatus and to suppress a variation in luminance within an image forming area.

[0030]

According to an aspect of the present invention, there is provided an image forming apparatus, comprising: an electron source substrate on which an electron source for emitting electrons according to an image signal is formed; An image forming apparatus having a face plate on which a phosphor film is formed, wherein a non-evaporable getter layer comprising particles having a diameter of 1 μm or more and 10 μm or less is formed on the entire surface of the electron source substrate surface. .

That is, in the image forming apparatus of the present invention, by arranging the getter layer in the phosphor boundary region of the image forming member, the gas adsorbing layer is disposed in a large area and near the part which emits gas most. As a result, the gas generated in the envelope is quickly adsorbed to the getter layer, and the degree of vacuum in the envelope can be maintained in a good state, so that the amount of electrons emitted from the electron source is stabilized. Can be As described above, the image forming apparatus of the present invention does not require a special mechanism and process for activating the getter material, and can arrange the getter material in a wide area and near the gas releasing member.

Further, the method of manufacturing an image forming apparatus of the present invention comprises:
A method of manufacturing an image forming apparatus, comprising: an electron source substrate on which an electron source that emits electrons according to an image signal is formed; and a face plate on which a phosphor film that receives and emits electrons is formed. 1 μm in diameter over the entire surface of the substrate
After forming a non-evaporable getter layer composed of particles of 10 μm or less and forming a non-evaporable getter layer, the front electron source substrate is fixed to a rear plate, and the surface of the electron source substrate is set at a predetermined temperature or lower. A rear plate and the face plate are sealed, the inside of the image forming apparatus is evacuated, and the electron source substrate is baked at the predetermined temperature or higher.

That is, in the method of manufacturing an image forming apparatus according to the present invention, a getter material having a granularity of 1 to 10 micrometers is used to form a getter layer on an electron source substrate, and then use an inert gas such as nitrogen gas. To cover the getter surface and keep the surface in a stable state.
Further, the stabilized getter material surface can also serve as a getter activation step by the baking step of the image forming apparatus, and the getter characteristics can be developed by this step. The method of the present invention also has a method of activating a getter of the image forming apparatus, wherein a temperature of an electron source substrate surface in an assembling process of the image forming apparatus is
The temperature of the electron source substrate is set lower than that in a baking step after evacuation, and the getter layer can be activated by the baking step of the image forming apparatus.

[0034]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows an example of the configuration of the image forming apparatus of the present invention.

Reference numeral 1 denotes an electron source, which has a plurality of electron-emitting devices arranged on a substrate and appropriately electrically connected by Doxn X-direction wiring and Doyn Y-direction wiring. Reference numeral 2 denotes a rear plate, reference numeral 3 denotes a support frame, and reference numeral 4 denotes a face plate. At a joint portion, they are adhered to each other using frit glass or the like to form an envelope 5. Reference numeral 9 denotes a getter formed on the rear plate.

The face plate 4 has a fluorescent film 7, a metal back 8, and a transparent conductive film (not shown) formed on a glass substrate 6, and this portion becomes an image display area. The fluorescent film 7 is made of only a phosphor in the case of a black-and-white image, but in the case of displaying a color image, pixels are formed by phosphors of three primary colors of red, green and blue.

The metal back 8 is formed of a conductive thin film such as Al. The metal back 8 reflects light traveling toward the electron source 1 out of the light emitted from the phosphor toward the glass substrate 6 to improve the brightness, and the gas remaining in the envelope 5 reduces the electron emission. It also serves to prevent the phosphor from being damaged by the impact of ions generated by ionization by the wire. Further, it provides conductivity to the image display area of the face plate 4 to prevent charge from being accumulated, and serves as an anode electrode for the electron source 1.

Next, the fluorescent film 7 will be described. FIG.
(A) is a case where the phosphors 7 are arranged in a stripe shape, and the phosphors 7 of three primary colors of red (R), green (G), and blue (B).
Are formed in order. FIG. 2B shows a case where the dots of the phosphor 7 are arranged in a grid pattern. There are several methods of arranging the respective colors. In accordance with this, the dot arrangement type is a triangular grid as shown in FIG. May be adopted. In addition, a black conductive material 10 is disposed at a boundary between the phosphors.

As a method of patterning the phosphor 7 on the glass substrate 6, a slurry method or a printing method can be used.
After the fluorescent film 7 is formed, a metal such as Al is further formed to form a metal back 8.

Next, the getter layer arranged on the rear plate, which is a feature of the present invention, will be described with reference to FIG.

In the figure, 1 is an electron-emitting device, 2 is a glass substrate, 11 is a wiring on a matrix, 12 is a lower wiring, 1
3 is an interlayer insulating layer between the upper and lower wirings, and 9 is a getter material.
The electron-emitting device shown here is an electron source in which a plurality of matrix-wired electron-emitting devices are arranged on a substrate, and the electron-emitting device is a surface conduction electron-emitting device or a horizontal field-emission electron-emitting device. This is a device using an emission element.

The getter material, which is a feature of the present invention, is an aggregate of particles having a granularity of 1 to 10 micrometers as described above, and has a thickness of about 1 to over a dozen layers.
It is formed on the rear plate surface.

The location of the getter may be on the surface of the two glass substrates, on the upper wiring 11 or on the lower wiring 12, or on a combination of the above-mentioned parts, for example, on the surface of both upper and lower wirings. The getter may be arranged on the interlayer insulating layer by appropriately selecting the thicknesses of the 13 interlayer insulating layer and the getter.

Further, in the above-mentioned surface conduction type electron-emitting device and horizontal field emitter, if the distance between the pair of electrodes is set to be equal to or larger than the particle diameter of the getter material and the getter material is arranged as a discontinuous film, the getter will be formed on the electron-emitting device. Can also be provided.

If the substrate is designed so as to satisfy the above conditions, the getter material of the present invention can be arranged on the entire rear plate.

Further, if a short circuit between the electron-emitting devices or the upper and lower wirings is difficult to avoid due to the getter material arrangement, after the interlayer insulating layer, the upper and lower wirings and the electron-emitting devices are formed on the substrate, the electron-emitting device portion is removed. A method is conceivable in which an insulating layer is formed of an electrically insulating material, for example, an oxide of silicon or the like, on the substrate to be removed, and a getter material is disposed over the entire surface of the insulating layer.

By doing so, it is possible to completely eliminate the short circuit between the wirings, and the degree of freedom in designing the rear plate configuration is increased.

Next, a method for forming the getter layer 9 will be described.

In the present invention, the getter layer 9 is 1 to 10
It must have a micrometer granularity and must be in such a form that after the getter activation, an active surface capable of exhibiting gas adsorption characteristics can be obtained.

Therefore, the vacuum deposition method and the sputtering method using an electron beam as shown in the above-mentioned "anode plate" cannot be applied. The reason for this is that although a uniform thin film can be formed by the above-described vacuum deposition, it is difficult to obtain the required granularity on the order of micrometers.

A method of bonding a material having a desired granularity to a desired position with a conductive adhesive or the like is also conceivable. However, the method is realized because the adhesive covers the particle surface and a clean surface cannot be obtained. It is difficult.

Here, the granularity of the getter required in the present invention will be described. Since the non-evaporable getter used in the present invention has undergone the steps of gas adsorption to the active surface and diffusion into the interior, the granularity contributes to an increase in surface area, and its film thickness contributes to the total amount of gas that can be adsorbed.

Therefore, if a sufficient surface area can be ensured, getter characteristics can be expected even in the above-mentioned vacuum deposition method, but a film obtained by vapor deposition is a collection of fine particles and is in an extremely active state immediately after the getter formation. Therefore, gas is adsorbed by taking out from the vacuum device, and the ability as a getter is lost. This means the same difficulty as the evaporable getter. In addition, the aforementioned U.S. Pat.
In the case of vacuum deposition described in Japanese Patent No. 3,659, it is difficult to increase the film thickness to submicron or more from the viewpoints of adhesion and throughput. It deteriorates remarkably.

On the other hand, in order to utilize surface adsorption, a clean surface of the constituent material is indispensable, and this is usually obtained through a step of activation. However, when the getter material is fixed with an adhesive or the like, the surface is covered, and in the subsequent activation step, an active surface cannot be obtained, and sufficient characteristics cannot be obtained.

For the above reasons, it is desirable to use a thermal spraying technique performed in a vacuum or in an inert gas as a method for manufacturing the getter layer of the present invention. In particular, by using a plasma spraying technique performed under reduced pressure, a getter layer having a desired thickness can be formed while maintaining desired granularity.

In the plasma spraying, a powder of a desired material is supplied into a plasma flame and is applied to a substrate, a member or the like on which a semi-molten material is to be formed. The properties can be controlled by the particle size of the supplied powder itself and the power of the plasma, and the composition can be controlled by controlling the composition of the powder.

Next, the manufacturing process of the rear plate shown in FIG. 3 will be described.

The lower wiring, the interlayer insulating layer, the upper wiring, and the electron-emitting device shown in FIG. 3 are formed on the glass substrate 2 by using ordinary photolithography or printing. As an example, the electron-emitting device can be manufactured by vacuum deposition and ordinary photolithography, the interlayer insulating layer, and the upper and lower wirings by a printing method or the like.

It is necessary to select a certain thickness and size of the interlayer insulating layer in order to prevent a short circuit between the upper and lower wirings and also serve as electrical insulation after the getter material is arranged.

Specifically, the getter material can be arranged on the entire rear plate by setting the distance between a pair of electrodes of the electron source and the thickness of the interlayer insulating layer to be about 2 to 10 times the getter particle size. Note that these manufacturing methods are not particularly limited, and any method may be used.

As described above, as a method of forming the getter material disposed on the entire surface of the substrate obtained as described above, Ti, Zr, V, Hf, M
A getter material made of a powder such as n is sprayed to form a getter layer 9. The thickness of the getter material can be appropriately selected in the range of 1 micrometer to 20 micrometers,
The thickness is preferably about 10 micrometers from the balance between the adsorption characteristics of the getter material and the prevention of short circuit between the upper and lower wiring.

Next, a method of assembling the rear plate and the image forming member obtained as described above will be described.

Normally, when manufacturing an image forming apparatus that maintains the inside of the envelope in a vacuum, frit glass, which is a sealing material, is applied or arranged between glass members, and the entire image forming apparatus is placed in an electric furnace or the like. A sealing method is used in which the glass member at the sealing portion is fused by heating to a sealing temperature. However, since the image forming apparatus of the present invention has a non-evaporable getter inside the envelope and has no means for activating the getter material, getter damage at the time of sealing is minimized and assembly is completed. It is necessary to activate the getter by the subsequent vacuum baking. Therefore, the following two types of sealing methods for suppressing getter damage are considered in the present invention.

1. A normal sealing temperature is used in an inert gas such as argon.

2. The temperature of the rear plate is lowered from the normal sealing temperature, and only the sealing portion is set to the glass fusion temperature.

When sealing is performed in an inert gas, a normal sealing temperature of about 420 ° C. to 450 ° C. may be used, and when sealing the rear plate at a low temperature, the temperature of the rear plate is equal to or lower than the sealing temperature. , Desirably below the softening point of the frit glass.

In the present invention, as an example of a technique of lowering the rear plate temperature of the getter formation portion at the time of sealing from the normal sealing temperature and setting only the sealing portion to the glass fusion temperature, the rear plate is heated to about 300 ° C. After heating (this is called assist heating), there is a method in which laser irradiation is performed only on the sealing portion to raise the temperature to the sealing temperature to fuse the glass.

The face plate 4 formed as described above, the support frame 3, the rear plate 2, the electron source 1 and other structures are combined, and the support frame 3, the face plate 4, and the rear plate 2 are joined. I do. The joining is performed by attaching frit glass to the joining portion and heating the frit portion to about 420 ° C. Rear plate assist heating temperature is 350
° C.

Thereafter, necessary processing such as activation of the electron source 1 is performed, and the inside of the envelope 5 is sufficiently evacuated.
After baking is performed at a temperature equal to or higher than the assist heating temperature of about 0 ° C., gas is exhausted from the inside of the panel and the getter is activated, and then an exhaust pipe (not shown) is heated and closed with a burner.

In the following description of the present specification, the word “activation” indicating two different types of processing appears.
The first is activation of the electron-emitting device. The electron-emitting device is
In some cases, only the formation of the macroscopic shape does not emit electrons at all, or emits very little electrons. This means that the surface is subjected to a treatment such as surface modification so that electron emission of a desired intensity occurs.

The second is activation of the getter material. Z
By diffusing surface adsorbed atoms into the getter material by a method such as heating a non-evaporable getter formed on the image forming member in a vacuum containing r, Ti or the like as a main component,
This means that a clean surface is formed and a getter action is developed. In the following, when necessary to avoid confusion, "getter activation"
Use the word

In the image display device of this embodiment, the getter is activated by a baking process after evacuating the inside of the panel.

As described above, by forming the getter layer in the image display area on the rear plate surface, a wider getter area can be secured. In addition, it is possible to arrange the getter very close to the part where the gas is released most intensely with the operation, not only to keep the pressure inside the envelope of the image forming apparatus low, but also to quickly generate the generated gas. Then, it is possible to suppress the deterioration of the characteristics of the electron-emitting device and the fluctuation of the emission current amount. Next, an example of the configuration of a drive circuit for performing television display based on an NTSC television signal by the image forming apparatus will be described with reference to FIG. In FIG. 4, 41 is an image display device, 42 is a scanning circuit, 43 is a control circuit, and 44 is a shift register. 45 is a line memory, 46 is a synchronization signal separation circuit, 47 is a modulation signal generator, and Vx and Va are DC voltage sources. The image forming apparatus 41 includes terminals Dox1 to Doxm, terminals Doy1 to Doyn, and a high-voltage terminal H.
It is connected to an external electric circuit via v. Terminal Dox
1 to Doxm are used to sequentially drive electron sources provided in the image forming apparatus, that is, a group of surface conduction electron-emitting devices arranged in a matrix of M rows and N columns, one row (N elements) at a time. Are applied.

To the terminals Doy1 to Doyn, a modulation signal for controlling the output electron beam of each element of the surface conduction electron-emitting device in one row selected by the scanning signal is applied. The high-voltage terminal Hv is supplied with a DC voltage of, for example, 10 kV from a DC voltage source Va, which applies sufficient energy to an electron beam emitted from the surface conduction electron-emitting device to excite the phosphor. This is the accelerating voltage to perform.

The scanning circuit 42 will be described. This circuit includes M switching elements inside (in the drawing, S1 to Sm are schematically shown). Each switching element selects either the output voltage of the DC voltage source Vx or 0 V (ground level), and is electrically connected to the terminals Dox1 to Doxm of the image forming apparatus 41. Each of the switching elements S1 to Sm operates based on the control signal Tscan output from the control circuit 43, and can be configured by combining switching elements such as FETs, for example.

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

The control circuit 43 has a function of matching the operation of each unit so that an appropriate display is performed based on an image signal input from the outside. The control circuit 43 sends Tscan, Tsft, and Tm to each unit based on the synchronization signal Tsync sent from the synchronization signal separation circuit 46.
ry control signals are generated.

The synchronizing signal separation circuit 46 is a circuit for separating a synchronizing signal component and a luminance signal component from an NTSC television signal input from the outside, and uses a general frequency separation (filter) circuit or the like. Can be configured. The synchronizing signal separated by the synchronizing signal separating circuit 46 includes a vertical synchronizing signal and a horizontal synchronizing signal.
This is shown as a SYNC signal. The luminance signal component of the image separated from the television signal is referred to as a DATA signal for convenience. The DATA signal is input to the shift register 44.

The shift register 44 is for serially / parallel converting the DATA signal input serially in time series for each line of an image, and is based on a control signal Tsft sent from the control circuit 43. (Ie, the control signal Tsft is supplied to the shift register 44).
It can be said that it is a shift clock. ). The data for one line of the image that has been subjected to the serial / parallel conversion (corresponding to the drive data for the N-electron emitting elements) is converted into N parallel signals Id1 to Idn as the above-mentioned shift register 4
4 is output.

The line memory 45 is a storage device for storing data for one line of an image for a required time only.
According to the control signal Tmry sent from the control circuit 43, the contents of Id1 to Idn are stored as appropriate. The stored contents are output as I'd1 to I'dn and input to the modulation signal generator 47.

The modulation signal generator 47 outputs the image data I'd
1 to I′dn are signal sources for appropriately driving and modulating each of the surface conduction electron-emitting devices in accordance with each of the surface conduction electron-emitting devices. Applied to the emitting element.

The electron-emitting device to which the present invention can be applied has the following basic characteristics with respect to the emission current Ie. That is, electron emission has a clear threshold voltage Vth, and electron emission occurs only when a voltage equal to or higher than Vth is applied. For a voltage equal to or higher than the electron emission threshold, the emission current also changes according to the change in the voltage applied to the device. From this, when a pulse-like voltage is applied to this element, for example, when a voltage lower than the electron emission threshold is applied, electron emission does not occur, but when a voltage higher than the electron emission threshold is applied, the electron beam is emitted. Is output. At that time, the intensity of the output electron beam can be controlled by changing the pulse peak value Vm. In addition, it is possible to control the total amount of charges of the output electron beam by changing the pulse width Pw.

Therefore, as a method of modulating the electron-emitting device in accordance with the input signal, a voltage modulation method, a pulse width modulation method, or the like can be employed. When implementing the voltage modulation method, a circuit of the voltage modulation method that generates a voltage pulse of a fixed length and modulates the peak value of the pulse appropriately according to input data is used as the modulation signal generator 47. be able to.

When implementing the pulse width modulation method,
As the modulation signal generator 47, 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 can be used.

The shift register 44 and the line memory 45
The digital signal type and the analog signal type can be adopted. This is because the serial / parallel conversion and storage of the image signal may be performed at a predetermined speed.

When the digital signal type is used, it is necessary to convert the output signal DATA of the synchronizing signal separating circuit 46 into a digital signal. For this purpose, an A / D converter may be provided at the output section 46.

In connection with this, the circuit used for the modulation signal generator 47 differs slightly depending on whether the output signal of the line memory 45 is a digital signal or an analog signal.
That is, in the case of the voltage modulation method using a digital signal, for example, a D / A conversion circuit is used as the modulation signal generator 47, and an amplification circuit or the like is added as necessary. In the case of the pulse width modulation method, the modulation signal generator 47 includes, for example, a high-speed oscillator, a counter for counting the number of waves output from the oscillator, and a comparator for comparing the output value of the counter with the output value of the memory. (Comparator) is used.
If necessary, an amplifier for voltage-amplifying the pulse width modulated signal output from the comparator to the drive voltage of the surface conduction electron-emitting device can be added.

In the case of the voltage modulation method using an analog signal, an amplification circuit using, for example, an operational amplifier can be used as the modulation signal generator 47, and a level shift circuit and the like can be added as needed. In the case of the pulse width modulation method, for example, a voltage-controlled oscillation circuit (VOC) can be employed, and an amplifier for amplifying the voltage up to the drive voltage of the surface conduction electron-emitting device can be added as necessary.

In the image forming apparatus of the present invention which can have such a configuration, each of the electron-emitting devices is provided with an external terminal Do.
By applying a voltage via x1 to Doxm and Doy1 to Doyn, electron emission occurs. High voltage terminal H
A high voltage is applied to the metal back 8 or a transparent electrode (not shown) through the v to accelerate the electron beam. The accelerated electrons collide with the fluorescent film 7 and emit light to form an image.

The configuration of the image forming apparatus described here is an example of an image forming apparatus to which the present invention can be applied, and various modifications can be made based on the technical idea of the present invention. Although the NTSC system has been described as the input signal, the input signal is not limited to the NTSC system, but may be a PAL or SECAM system, or a TV signal (for example, M
A high-definition TV) system such as the USE system can also be adopted.

The image forming apparatus of the present invention can be used not only as a display device for a television broadcast, a display device such as a video conference system and a computer, but also as an image forming device as an optical printer using a photosensitive drum or the like. Can be used.

[0093]

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

Embodiment 1 The image forming apparatus of this embodiment has the same configuration as the apparatus schematically shown in FIG. 1, and the getter layer 9 is arranged on the entire surface of the rear plate 2.

The image forming apparatus of this embodiment has an electron source 1 in which a plurality of (100 rows × 300 columns) surface conduction electron-emitting devices are arranged in a simple matrix on a substrate.

FIG. 5 is a plan view of a part of the electron source 1. FIG. 6 is a sectional view taken along the line AA ′ in the figure. However, FIG.
In FIG. 6, the same symbols indicate the same items. Here, 111 is an electron source substrate, 82 is an X-direction wiring (also referred to as a lower wiring) corresponding to Doxm in FIG. 1, and 83 is Do in FIG.
Y-direction wiring corresponding to yn (also referred to as upper wiring), 102
Is a conductive film including an electron emitting portion, 105 and 106 are device electrodes, 141 is an interlayer insulating layer, and 142 is a contact hole for electrical connection between the device electrode 105 and the lower wiring 82.

Hereinafter, a method for manufacturing the image forming apparatus of this embodiment will be described with reference to FIGS. Step-a On the electron source substrate 111 in which a 0.5 μm thick silicon oxide film is formed on a cleaned blue plate glass by a sputtering method, 5 nm thick Cr and 600 nm thick Au are deposited by vacuum evaporation.
After sequentially laminating, a photoresist (manufactured by AZ1370 Hoechst) is spin-coated with a spinner and baked.
The photomask image is exposed and developed to form a resist pattern of the lower wiring 82, and the Au / Cr deposited film is wet-etched to form the lower wiring 82 having a desired shape (FIG. 7A).

Step-b Next, an interlayer insulating layer 141 made of a silicon oxide film having a thickness of 20 μm is deposited by a printing method (FIG. 7B).

Step-c A photoresist pattern for forming the contact hole 142 is formed in the silicon oxide film deposited in the step b, and the interlayer insulating layer 141 is etched using the photoresist pattern as a mask to form the contact hole 142. Etching is performed by RIE (Reactive I) using CF ₄ and H ₂ gas.
on Etching) method (FIG. 7 (c)).

Step-d Thereafter, a pattern to be a gap G between the device electrode 105 and the device electrode is formed by a photoresist (RD-2000N-41).
Hitachi Chemical Co., Ltd.) and a thickness of 5 n
m of Ti and 100 nm of Ni were sequentially deposited. The photoresist pattern was dissolved with an organic solvent, the Ni / Ti deposited film was lifted off, and the device electrodes 105 and 106 were formed with the device electrode interval G of 3 μm and the device electrode width of 300 μm (FIG. 7D).

Step-e After a photoresist pattern of the upper wiring 83 is formed on the device electrodes 105 and 106, Ti having a thickness of 5 nm and a thickness of 50
0 nm of Au is sequentially deposited by vacuum evaporation, unnecessary portions are removed by lift-off, and the upper wiring 8 of a desired shape is removed.
No. 3 was formed (FIG. 8E).

Step-f A Cr film 151 having a thickness of 100 nm is deposited by vacuum evaporation.
After patterning, a Pd amine complex solution (cc
p4230 Okuno Pharmaceutical Co., Ltd.) was spin-coated with a spinner and heated and baked at 300 ° C. for 10 minutes. Further, the thus formed conductive film 102 for forming an electron emitting portion composed of fine particles made of Pd as a main element had a thickness of 8.5 nm and a sheet resistance value of 3.9 × 10 ⁴ Ω / □. . The fine particle film described here is, as described above, a film in which a plurality of fine particles are aggregated, and as its fine structure, not only a state in which the fine particles are individually dispersed and arranged, but also the fine particles are adjacent to each other or overlap each other. A film in a state (including an island shape) is referred to, and the particle size refers to the diameter of a fine particle whose particle shape can be recognized in the above state (FIG. 8 (f)).

Step-g A desired pattern was formed by etching the Cr film 151 and the conductive film 102 for forming the electron emission portion after firing with an acid etchant (FIG. 8 (g)).

Step-h A pattern was formed such that a resist was applied to portions other than the contact hole 142, and 5 nm thick Ti and 500 nm thick Au were sequentially deposited by vacuum evaporation. Unnecessary portions were removed by lift-off to bury the contact holes 142 (FIG. 8H).

Through the above steps, a plurality of (100 rows × 300 columns) conductive films 102 for forming electron emitting portions are formed on the electron source substrate 111 by a simple matrix wiring with the upper wiring 83 and the lower wiring 82. 1 was formed.

Next, Zr, Zr were applied on the entire surface of the rear plate obtained by the above-described process in a reduced pressure plasma spraying apparatus.
A getter material composed of V and Mn was deposited to form a getter layer. After the spraying was completed, the system was sufficiently cooled, and nitrogen gas was introduced into the apparatus to stabilize the surface of the getter, thereby completing the production of the rear plate on which the getter material was disposed. The particle size of the getter layer obtained in this step was 2 to 8 micrometers, and the average film thickness was about 10 micrometers.

Step-i Next, the face plate 4 was manufactured as follows.

A fluorescent film 7 was formed on the surface of the glass substrate 6 by a printing method. The fluorescent film 7 was a fluorescent film shown in FIG. 2A in which stripe-shaped phosphors (R, G, B) 13 and black conductive materials (black stripes) 12 were alternately arranged. Further, a metal back 8 made of an Al thin film was formed on the fluorescent film 7 to a thickness of 50 nm by a sputtering method. Step-j Next, the envelope 5 shown in FIG. 1 was manufactured as follows.

After fixing the electron source 1 manufactured by the above-described process to the rear plate 2, the support frame 3 and the face plate 4 are combined, and the lower wiring 82 and the upper wiring 83 of the electron source 1 are connected to the row selection terminals 10. And the signal input terminal 11, and the positions of the electron source 1 and the face plate 4 were strictly adjusted and sealed to form the envelope 5. The sealing method is
Frit glass was applied to the joining portion, the temperature of the image display area of the rear plate was set to 300 ° C., and the fused portion was heated to 450 ° C. by laser irradiation from the outside of the panel and heat-treated for 10 minutes to join.

Before describing the next step, the vacuum processing apparatus used in the subsequent steps will be described with reference to FIG.

The image display device 91 is connected to a vacuum container 93 via an exhaust pipe 92. The vacuum container 93 is connected to an exhaust device 95, and a gate valve 94 is provided therebetween. A pressure gauge 96 and a quadrupole mass spectrometer (Q-mass) 97 are attached to the vacuum vessel 93 so that the internal pressure and each partial pressure of the residual gas can be monitored. Since it is difficult to directly measure the pressure and the partial pressure in the envelope 5, the pressure and the partial pressure of the vacuum vessel 93 are measured, and these values are regarded as those in the envelope 5. Exhaust device 95
Is an ultra-high vacuum evacuation device consisting of a sorption pump and an ion pump. A plurality of gas introduction devices are connected to the vacuum vessel 93, and the substance stored in the substance source 99 can be introduced. Depending on the type of substance to be introduced,
The gas is filled in a cylinder or an ampule, and the gas introduction amount control means 98 can control the introduction amount. As the gas introduction amount control means 98, a needle valve, a mass flow controller, or the like is used according to the type of introduced substance, flow rate, required control accuracy, and the like. In this embodiment, acetone (CH ₃ ) ₂ CO contained in a glass ampoule was used as the substance source 99, and a slow leak valve was used as the gas introduction amount control means 98.

The following steps were performed using the above vacuum processing apparatus.

Step-k The inside of the envelope 5 is evacuated to a pressure of 1 × 10 ⁻³ Pa or less, and the conductive films 102 for forming a plurality of electron emitting portions arranged on the electron source substrate 111 are formed. (FIG. 8 (h)) was subjected to the following forming process for forming an electron-emitting portion.

As shown in FIG. 10, the Y-direction wirings 22 are connected in common and connected to the ground. A control device 51 controls a pulse generator 52 and a line selection device 54. 53
Is an ammeter. The line selection device 54 selects one line from the X-direction wiring 23 and applies a pulse voltage to it. The forming process was performed for each element row in the X direction (300 elements). The waveform of the applied pulse is
The peak value was gradually increased with a triangular wave pulse as shown in FIG. Pulse width T1 = 1 msec. , Pulse interval T2 = 10 msec. And Further, a rectangular wave pulse having a peak value of 0.1 V was inserted between the triangular wave pulses, and the current was measured to measure the resistance value of each row. When the resistance value exceeds 3.3 kΩ (1 MΩ per element),
The forming of the line is completed, and the process proceeds to the next line. This process is performed for all the rows, the forming of all the conductive films (the conductive film 102 for forming the electron-emitting portions) is completed, and the electron-emitting portions are formed in each of the conductive films. An electron source 1 in which emission elements were wired in a simple matrix was prepared.

Step-1 Acetone (CH ₃ ) ₂ CO and hydrogen H ₂ were introduced into the vacuum vessel 43, and the partial pressure of each was (CH ₃ ) ₂ CO; 1.3 × 1
0 ⁻³ Pa, H ₂ : 1.3 × 10 ⁻² Pa, and a pulse is applied to the electron source 1 while measuring the device current If to activate each electron-emitting device. Was. The pulse waveform generated by the pulse generator 52 is shown in FIG.
, The peak value is 14V, and the pulse interval is T1.
= 100 μsec. The pulse interval is 167 μsec. It is. 167 μsec. The selection line is sequentially switched from Dx1 to Dx100 every time. As a result, T1 = 100 μsec. ,
T2 = 16.7 msec. Is applied with a slightly shifted phase for each row.

The ammeter 53 is used in a mode for detecting the average of the current value in the ON state of the rectangular wave pulse (when the voltage is 14 V), and this value becomes 600 mA (2 mA per element). At this point, the activation process ends,
The inside of the envelope 5 was evacuated.

Step-m While the evacuation is continued, the entire image display device 91 and the vacuum vessel 93 are heated to 350 ° C. by a heating device (not shown) at 24 ° C.
Hold for hours. By this processing, it is considered that (CH ₃ ) ₂ was adsorbed to the envelope 5 and the inner wall of the vacuum vessel 93.
CO and its decomposition products were removed, and the getter material placed on the rear plate was activated.

Step-n After confirming that the pressure was 1.3 × 10 ⁻⁵ Pa or less, the exhaust pipe was heated with a burner and sealed off.

Thus, the image display device of this example was manufactured.

Embodiment 2 In this embodiment, an image is obtained in which a getter material made of Ti-Al is arranged on the entire surface of the substrate after overcoating a silicon oxide film on a portion other than the device portion on the rear plate where the wiring and the electron-emitting device are formed. It is an example of creation of a forming device.

First, the steps up to the step -h are performed in the same manner as in the first embodiment, and a rear plate on which electron sources of 100 × 300 elements are arranged is manufactured. Then, a silicon oxide film is formed to a thickness of 5 μm by RF sputtering. Then, a Ti-Al getter layer having a thickness of 20 micrometers was formed on the entire surface of the substrate by plasma spraying.
%, And 15% Al.

Next, after the pulse was formed by the same sealing process as in the first embodiment, the forming process was performed by using a high vacuum exhaust device constituted by a rotary pump and a turbo pump as an exhaust device of the vacuum processing apparatus. The pressure in the vacuum apparatus is set to 1.3 × 10 ⁻⁴ Pa or less, and the activation process is performed in the same manner as in the step-k of the first embodiment.
The same pulse as described above was applied.

No gas was introduced into the vacuum vessel, and carbon was deposited using an organic substance slightly remaining in the vacuum vessel due to diffusion from the exhaust device. At this time, the pressure in the vacuum vessel was 2.7 × 1
It was about 0 ^-3 Pa.

After the activation was completed, the device current If and the emission current Ie were measured by applying 16 V. The average value per device was If = 2.2 mA and Ie = 2.2 μA.
Met.

Subsequently, the entire panel was heated to about 350 ° C. to perform degassing and getter activation of the panel.

Subsequently, the exhaust pipe was heated and closed with a burner in the same manner as in Step-n of Example 1 to produce an image forming apparatus of this example.

[0127]

According to the present invention described above, the gas generated in the envelope is quickly adsorbed on the getter material by disposing the getter material on the entire rear plate forming the electron source. In addition, it is possible to suppress the deterioration of the characteristics of the electron-emitting device, and as a result, it is possible to suppress a decrease in luminance when the device is operated for a long time, particularly, a decrease in luminance near the center of the image display area.

Further, according to the present invention, the getter material can be activated by the vacuum baking step by lowering the rear plate temperature at the time of sealing.

[Brief description of the drawings]

FIG. 1 is a partially broken perspective view showing a structure of an envelope which is an embodiment of an image forming apparatus according to the present invention.

FIG. 2 is a diagram illustrating a structure of a fluorescent film.

FIG. 3 is a plan view showing a structure of a rear plate which is an embodiment of the image forming apparatus according to the present invention.

FIG. 4 is a block diagram illustrating a configuration example of a driving circuit for performing television display based on an NTSC television signal by an image display device in which a matrix arrangement is configured using an electron source.

FIG. 5 is a plan view schematically showing an electron source in which a plurality of surface conduction electron-emitting devices are arranged in a matrix.

FIG. 6 is a sectional view taken along line AA ′ of the electron source shown in FIG. 5;

FIG. 7 is a view for explaining a manufacturing process of the electron source shown in FIG. 5;

FIG. 8 is a view for explaining a manufacturing process of the electron source shown in FIG. 5;

FIG. 9 is a schematic view showing an outline of a vacuum processing apparatus used for manufacturing an image display device.

FIG. 10 is a schematic diagram illustrating a configuration of a circuit used for a manufacturing process, a forming process, and an activation process of the image display device.

FIG. 11 is a diagram showing an example of a voltage waveform applied at the time of forming processing.

FIG. 12 is a cross-sectional view of a part related to getter processing of a conventional flat panel image display device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electron source 2 rear plate 3 support frame 4 image forming member 5 envelope 6 glass substrate 7 fluorescent film 8 metal back 9 transparent conductive film 10 getter material 11 metal mask 12 opening 13 sprayed particles 41 image display device 42 scanning circuit 43 Control circuit 44 Shift register 45 Line memory 46 Synchronous signal separation circuit 47 Modulation signal generator

Claims (10)

[Claims] 1. An image forming apparatus comprising: an electron source substrate on which an electron source that emits electrons in response to an image signal is formed; and a face plate on which a phosphor film that receives and emits the electrons is formed. The diameter is 1 over the whole surface of the electron source substrate.
An image forming apparatus, wherein a non-evaporable getter layer composed of particles having a size of not less than μm and not more than 10 μm is formed. 2. The image forming apparatus according to claim 1, wherein the particles include at least one of Ti and Zr. 3. The image forming apparatus according to claim 2, wherein the particles include at least one of Al, V, Fe, and Mn. 4. The thickness of the non-evaporable getter layer is 1 μm.
2. The image forming apparatus according to claim 1, wherein the thickness is 20 μm or less. 5. The image forming apparatus according to claim 1, wherein the electron source substrate is a substrate on which a plurality of electron-emitting devices are arranged as an electron source. 6. The image forming apparatus according to claim 5, wherein the electron source substrate is a substrate on which a plurality of electron-emitting devices are arranged in a matrix as electron sources. 7. The electron source substrate is formed on a lower wiring for selecting an X direction of the matrix of the electron-emitting devices, an interlayer insulating film for insulating the lower wiring, and on the interlayer insulating film. 7. The image forming apparatus according to claim 6, wherein the substrate is provided with the electron-emitting device and an upper wiring for selecting a Y direction of the matrix of the electron-emitting device. 8. The image forming apparatus according to claim 5, wherein the electron source is a surface conduction electron-emitting device. 9. A method for manufacturing an image forming apparatus, comprising: an electron source substrate on which an electron source that emits electrons according to an image signal is formed; and a face plate on which a phosphor film that receives and emits the electrons is formed. The entire surface of the electron source substrate surface is 10 μm in diameter of 1 μm or more.
forming a non-evaporable getter layer composed of particles having a particle size of not more than μm, forming the non-evaporable getter layer, fixing the front electron source substrate to a rear plate, and setting the surface of the electron source substrate to a predetermined temperature or lower to reduce the rear temperature. A method for manufacturing an image forming apparatus, comprising sealing a plate and the face plate, evacuating the inside of the image forming apparatus, and baking the electron source substrate at the predetermined temperature or higher. 10. The method for manufacturing an image forming apparatus according to claim 9, wherein said non-evaporable getter layer is formed by low-pressure plasma spraying.