JP2000251714A - Manufacture for image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for reducing getter degradation during sealing of a panel, by heat each components in vacuum at a temperature higher than a sealing temperature before sealing an envelope containing at least a non- evaporative getter. SOLUTION: After an electron source substrate 1 is fixed to a rear plate 11 heat treated in vacuum, it is combined with a support frame 12 and a face plate 13 that are heated in vacuum, the X-directional wiring 3 and the Y- directional wiring of the electron source substrate 1 are respectively connected to a row selecting terminal 5 and a signal input terminal 6, positions of the electron source substrate 1 and the face plate 13 are strictly adjusted, they are sealed to form an envelope 17. As a sealing method, a joint portion of each member is coated with flit glass and is temporarily baked at 300 deg.C, then respective members are combined, and heat treatment in Ar gas, at 400 deg.C, and for 10 minutes is performed for joining. Fixing of the electron source substrate 1 to the rear plate 11 is performed with similar treatment. Degradation of a characteristic of an electron emitting element is restrained, and brightness does not degrease even for a long time operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an image forming apparatus such as a display device or an exposure device, which includes a non-evaporable getter in a vacuum container.

[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 forming member and causing the phosphor to emit light to display an image, a vacuum vessel containing the electron source and the image forming member is used. The interior of the (envelope) must be kept at a high vacuum. The reason is that 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, reduces the amount of electron emission, and makes it impossible to display a bright image. It is. 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.

[0003] Usually, a vacuum container of an image forming apparatus is formed by combining glass members and bonding a bonding portion with frit glass or the like. This is done by an installed 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.

[0005] 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 is being developed. In this case, the volume of the vacuum vessel is smaller than that of a CRT. On the other hand, the area of the wall surface for discharging the gas does not decrease, and therefore, the pressure inside the container increases when the same amount of gas is generated, and the adverse effect due to this increases. In the case of a CRT, there is sufficient wall surface without an electron source and an image forming member inside the vacuum container, and the getter material as described above can be deposited on this portion. An electron source and an image forming member occupy much of the inner surface area. If the above-described vapor deposition type 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, the corners of the vacuum vessel are used for forming the getter film so that the getter material does not adhere to a region formed by the image forming member and the electron source (hereinafter, referred to as an “image display region”). It is conceivable that when the size of the flat display is increased to some extent, it becomes impossible 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.
Phosphor 123 and field emission device 124 disposed opposite to each other
A wire getter 122 is stretched outside the image display area between, for example, the outer peripheral portion, and the getter film 125 is formed on the outer peripheral wall surface by vapor deposition (Japanese Patent Laid-Open No. 5-151).
No. 916) and a method of attaching a getter chamber 129 having a getter material 128 for forming a getter film to the side of the space between the face plate 126 and the rear plate 127 as shown in FIG. JP-A-4-2896
Japanese Patent Laid-Open No. 1-235152, etc., and a method in which a space is provided between an electron source substrate and a rear plate of a vacuum vessel and a getter film is formed thereover has been proposed.

[0007] In the flat plate image forming apparatus, the problem of gas generation in the vacuum vessel includes the above-mentioned problems,
As described below, there is a problem that the pressure tends to increase locally.

In the case of a conventional CRT, the image forming member is separated from the electron source, and a getter film formed on the inner wall of the vacuum vessel is provided between the two. Is diffused widely until it reaches, and the-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 plate image forming apparatus, since the image forming member and the electron source are close to each other, gas generated from the image forming member reaches the electron source before sufficiently diffusing, and causes a local pressure increase. Bring. In particular, in the central part of the image forming region where a large amount of gas is generated by the irradiation of the electron beam, the gas cannot diffuse to the region where the getter film is formed, so that a local pressure rise is considered to be larger than in the peripheral part. . The generated gas is released from the electron source and is ionized by the electrons, which may cause damage between the electron source and the image forming member, or may cause an electric discharge to destroy the electron source.

In view of such circumstances, in a flat plate image forming apparatus having a specific structure, a structure is disclosed in which a getter material is arranged in an image display area to immediately adsorb generated gas. Have been. For example, JP-A-4-1243
Japanese Patent Application Laid-Open No. 6-26139 discloses a method of forming an electron source having a gate electrode for extracting an electron beam, wherein the gate electrode is formed of a getter material. Are exemplified. Japanese Patent Application Laid-Open No. 63-181248 discloses a flat display having a structure in which an electrode (grid or the like) for controlling an electron beam is arranged between a cathode (cathode) group and a face plate of a vacuum vessel.
A method of forming a getter material film on the control electrode is disclosed.

On the other hand, it is needless to say that an electron-emitting device constituting an electron source used in a flat display is simple in structure and manufacturing method from the viewpoint of production technology, manufacturing cost and the like. 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. 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.

An electron-emitting device having a structure capable of satisfying the above-mentioned requirement that the manufacturing process is easy is as follows.
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 the lithography technique, and an example is shown in Japanese Patent Application Laid-Open No. Hei 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, getters cannot be placed in the image display area in a similar manner,
Since the getter is disposed outside the image display area, it is difficult to avoid the deterioration, destruction, and the like due to the decrease in the degree of vacuum.

[0015]

As described above, in an apparatus that irradiates an electron beam emitted from an electron source to a phosphor as an image forming member and causes the phosphor to emit light, an image is displayed. The interior of the vacuum vessel containing the source and the imaging member must be maintained at a high vacuum.

In the above-described image forming apparatus, the most significant source of gas generation 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 to affect the characteristics, and gas molecules ionized by the electrons emitted from the electron source form a gap between the image forming member and the electron source or between the electron source and the positive electrode of the electron source. It is accelerated by the electric field formed by the voltage applied between the negative electrodes, and may collide with and damage the positive electrode or the negative electrode of the electron source.

Further, when the gas pressure is locally and instantaneously increased, ions accelerated by the electric field may collide with another gas molecule to 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 forming member emits electrons after the image forming apparatus is formed, thereby causing the phosphor to emit light.
H ₂ O, H ₂ , CH ₄ , CO, C contained in the phosphor
Gases such as O ₂ and O ₂ are rapidly released. This may cause phenomena such as a noticeable decrease in image brightness at the beginning of driving.

In order to solve such a problem, merely providing a getter region outside the display region as in the related art requires gas generated near the center of the image display region to reach the outer getter region in a short time. In addition to this, it is re-adsorbed by the electron source before being adsorbed by the getter, thereby deteriorating the electron emission characteristics. The getter layer provided on the outer periphery of the image display area cannot exert a sufficient effect to prevent the deterioration of the element. In particular, the brightness of the image may be noticeably reduced particularly at the center of the image display area. Therefore, in the flat plate image forming apparatus having no gate electrode or control electrode as described above, a device having a novel structure capable of disposing a getter member in an image display area so that generated gas is quickly removed. Was required to be created.

In order to solve the above problems, US Pat.
No. 453,659 "AnodePlate for
Flat Panel Display having
integrated Getter ”, issue
d 26 Sept. 1995 to Wallace
et al. Discloses a method in which a getter member is formed in a gap between stripe-shaped phosphors on an image forming substrate (anode plate). In this example, the getter material is electrically separated from the phosphor and the conductor electrically connected to the phosphor, so that an appropriate potential is applied to the getter to irradiate and heat the electrons emitted from the electron source. Then, the getter is activated. However, the getter material is formed by 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 and has a small surface area. Due to the nature of the non-evaporable getter, which absorbs gas by surface adsorption, a small surface area means that the properties of the getter (adsorption rate and total adsorption amount) are worsened. At the time of panel sealing, if the amount of gas released from the member is large, the getter may be deteriorated.

An object of the present invention is to provide a method of manufacturing an image forming apparatus capable of solving the above-mentioned disadvantages, and more particularly, to a method of manufacturing an image forming apparatus capable of reducing getter deterioration during panel sealing. The purpose is to provide.

[0021]

In order to achieve the above object, a method of manufacturing an image forming apparatus according to the present invention is directed to a method of manufacturing an image forming apparatus including at least a non-evaporable getter in an envelope. Before the step of sealing the envelope, each component is subjected to a heat treatment at a sealing temperature or higher in a vacuum.

The method for manufacturing an image forming apparatus of the present invention is as follows.
As a further feature, "the sealing of the envelope is melting and bonding with a low melting point glass frit", "the image forming apparatus has a plurality of electron-emitting devices disposed in the envelope. Having an electron source substrate and an image forming substrate provided with an image forming member ";" the electron emitting element is a surface conduction electron emitting element "; and Alternatively, "forming on the surface of the image forming substrate", "forming the non-evaporable getter on the electron source substrate or the image forming substrate previously heat-treated at a sealing temperature or higher in vacuum", ""The material of the non-evaporable getter is an alloy containing Ti or / and Zr as a main component and further containing any one or more of Al, V, Fe, and Mn as an auxiliary component." Activation of getter After the sealing of the envelope, the heat treatment is performed in a baking step of performing a heat treatment while evacuating the envelope, "and" the activation temperature of the non-evaporable getter is set to Lower than the sealing temperature '', `` the image forming apparatus includes a light emitting medium in an envelope in which a front substrate and a rear substrate on which a display electrode and an auxiliary electrode are formed on at least one of the substrates are opposed to each other. It is an image forming apparatus that performs display by enclosing and applying a voltage to the display electrode and the auxiliary electrode. "

The feature of the manufacturing process of the image forming apparatus of the present invention is that the constituent members of the image forming apparatus for forming the non-evaporable getter are heated in advance in a vacuum, and the desired constituent members, particularly preferably in the image display area, After forming a non-evaporable getter on an electron source substrate or an image forming substrate, a panel is formed by sealing. As described above, in the member heated in advance at the sealing temperature or higher, the release of gas at the sealing temperature is greatly reduced, and the deterioration of the characteristics of the non-evaporable getter in the sealing step can be suppressed.

The inventor of the present invention has made intensive studies on the deterioration of the characteristics of the non-evaporable getter in the image forming apparatus. As a result, the main components of the image forming apparatus, such as glass substrate, phosphor, wiring material, glass frit, etc. When heated at about the sealing temperature without passing through the heat treatment step, it was found that hydrogen, oxygen, water, carbon dioxide, carbon dioxide, etc. were generated. 4
When the above gas is present at a sealing temperature of about 00 ° C. to 450 ° C., the characteristic deterioration of the non-evaporable getter is remarkable. Of the adsorption speed becomes several tenths to several tenths.

On the other hand, as in the present invention, a getter is formed on the constituent member after the constituent member is subjected to the vacuum heating process,
Further, when sealing for panelization is performed with the constituent members that have been subjected to the vacuum heat treatment, deterioration of characteristics can be effectively suppressed.

However, even when a member subjected to a vacuum heat treatment is used, the effects of the present invention are reduced when the interior of the image forming apparatus is air when sealing with frit glass. Therefore, the sealing atmosphere to which the present invention can be applied is preferably in an inert gas such as argon or nitrogen gas.

However, even in an inert gas, if the constituent members are not subjected to the vacuum heating treatment, deterioration of the getter characteristics is inevitable due to the killer gas for the non-evaporable getter released from the members at the time of sealing. Needless to say.

On the other hand, when the member is subjected to a vacuum heat treatment in advance, gas emission in a temperature range from 300 ° C. or more to a sealing temperature (about 400 ° C. to 450 ° C.) where the getter is significantly deteriorated is drastically reduced. This is an effective getter protection measure.

As described above, in the case of a flat image forming apparatus, it is desirable to dispose a non-evaporable getter in the image display area in order to effectively exhaust gas generated by driving the electron source. In the image display area, the getter activity at high temperature can be easily obtained on the electron source substrate or the image forming substrate on which the fluorescent substance is arranged, which can be considered as a place where the getter can be arranged. This is on a member that is not suitable for performing gettering, and also prevents sufficient getter activation.

Therefore, in the present invention, it is preferable that a getter is arranged in the image display area, and after the panel is sealed, the getter is activated by using a vacuum baking step of the panel. Therefore, the activation temperature is limited to the sealing temperature or lower.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic structure of an image forming apparatus to which the present invention can be applied will be described below.

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

An electron source substrate 1 includes a plurality of electron-emitting devices 2.
Are arranged on a substrate, and are appropriately electrically connected by m X-directional wirings 3 and n Y-directional wirings 4. The X-directional wiring 3 and the Y-directional wiring 4 are respectively drawn out of the container as terminals _{Dox1 to Doxm} and _{Doy1 to Doyn} . Reference numeral 11 denotes a rear plate to which the electron source substrate 1 is fixed, 12 denotes a support frame, and 13 denotes a face plate which is an image forming substrate, and is bonded to each other using frit glass or the like at each joint to form an envelope 17. ing.

The face plate 13 comprises a glass substrate 14
A fluorescent film 15, a metal back 16, and a transparent conductive film (not shown) are formed thereon, and this portion becomes an image display area. The fluorescent film 15 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 of phosphors of three primary colors of red, green and blue.

The metal back 16 is formed of a conductive thin film of Al or the like. The metal back 16 reflects light traveling toward the electron source substrate 1 out of the light generated from the phosphor toward the glass base 14 to improve the brightness, and the gas remaining in the envelope 17 reduces the light emitted from the phosphor. 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 13 to prevent charge from being accumulated, and serves as an anode electrode for the electron source substrate 1.

Next, the fluorescent film 15 will be described. FIG.
(A) is a case where the phosphors 18 are arranged in a stripe shape, and the phosphors 1 of three primary colors of red (R), green (G), and blue (B).
8 are formed in order. FIG. 2B shows a case where the dots of the phosphor 18 are arranged in a grid pattern. There are several types of arrangement methods for each color. In some cases, such as is adopted. When a non-evaporable getter is formed on the face plate 13 side, a non-evaporable getter 19 can be formed in a region between the phosphors 18.

As a method of patterning the phosphor 18 on the glass substrate 14, a slurry method, a printing method, or the like can be used. After forming the fluorescent film 15, a metal such as Al is further formed to form a metal back 16.

Next, the electron source substrate 1 applicable to the present invention will be described.

The electron source substrate 1 is formed on an insulating substrate such as a glass substrate, or an insulating thin film by using a method such as photolithography or printing, and has an XY matrix arranged via an interlayer insulating layer. There are a device in which the electron-emitting devices 2 are arranged at the intersections of the wires, and a device in which the electron-emitting devices are arranged in parallel between two wires arranged in a ladder shape.

As the electron-emitting device 2 used here, a field emitter (a so-called Spindt type) comprising a fine conical cathode and a grid electrode for extracting electrons from the cathode, and a horizontal field emission having a planar structure of the field emitter are used. Type electron-emitting devices, surface conduction electron-emitting devices, and the like.

These electron-emitting devices are easily affected by the surface of the device during operation, and when applied to an image forming apparatus, the deterioration of the degree of vacuum in the envelope (panel) 17 causes deterioration of the characteristics or discharge. In some cases, the device may be destroyed due to the generation of the light, and a getter for maintaining a vacuum is required.

Next, the non-evaporable getter used in the present invention will be described.

The non-evaporable getter which can be used in the present invention is desirably disposed in the image display area of the image forming apparatus, and is disposed at the electron source substrate 1 (electron source substrate 1).
When a separate rear plate for fixing the electron source substrate is not used, the electron source substrate 1 itself is also called a rear plate. ) Or on a face plate which is an image forming substrate on which a phosphor is arranged.

The effect of the present invention can be obtained even when a ribbon-shaped getter is arranged in a panel other than the image display area, for example, on the outer periphery of the image display area. However, the gas released when the element is driven is quickly absorbed. As described above, it is not suitable for the ability to perform.

When a non-evaporable getter is arranged on the rear plate, heating is performed in a vacuum after forming matrix wiring and the like before forming the getter. The heating temperature is equal to or higher than a heating step after the formation of the getter, for example, a sealing temperature for sealing the rear plate and the face plate. Normally, when a sealing action is performed using a glass frit, heating is performed at a temperature of about 400 ° C. to 450 ° C., and therefore, a temperature of about 480 ° C. in a vacuum heat treatment of the constituent members is appropriate. The processing time may be maintained for about one hour.

When the non-evaporable getter is arranged on the face plate, as shown in FIG. 2, a region which is not irradiated with the electrons emitted from the electron-emitting device, for example, the three primary color phosphors 18 of red, blue and green. The non-evaporable getter layer 19 is arranged at the boundary of the.

The thickness of the non-evaporable getter formed on the rear plate or the face plate which has been subjected to the vacuum heat treatment can be appropriately selected within a range of about 10 μm to 200 μm.
In this case, the getter layer may be formed of two to several tens of layers as a particle layer.

Next, a method for manufacturing the non-evaporable getter layer 19 will be described.

The getter layer 19 in the present invention must be formed in such a form that an active surface capable of exhibiting gas adsorption characteristics can be obtained after the getter is activated.
It is preferable to have m granularity. Therefore, a vacuum evaporation method or a sputtering method using an electron beam as shown in the aforementioned US Pat. No. 5,453,659 cannot be applied. The reason 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 μm.

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

Here, the granularity required for the getter formed in the present invention will be described. Since the exhaust by the non-evaporable getter used in the present invention has undergone a process of gas adsorption to the active surface and diffusion into the interior, the granularity contributes to an increase in the surface area, and the film thickness is reduced by the total amount of adsorbable gas. Contribute.

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 formation of the getter. Therefore, the gas is adsorbed by being taken out of the vacuum device, and the ability as a getter is lost. This means the same difficulty as the evaporable getter. No. 5,453,65 mentioned above.
In the case of vacuum deposition described in No. 9, it is difficult to make the film thickness of submicron or more from the viewpoint of adhesion and throughput, and when the film thickness is several μm or less, the characteristics are significantly deteriorated in the sealing step. .

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, if 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,
Sufficient characteristics cannot be obtained.

For the above reasons, as an example of the method for manufacturing the getter layer of the present invention, there is a thermal spraying technique performed in a vacuum or in an inert gas. 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 a material in a semi-molten state is applied to a substrate / member to be formed, thereby forming a film. The granularity 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.

The patterning method includes etching and lift-off using a normal photolithography technique,
Alternatively, a method such as using a patterned metal mask may be used.

As described above, after the constituent members are subjected to the vacuum heat treatment, the members having the getters formed on the face plate or the rear plate are combined with other structural members and joined to form a panel. The joining is performed by attaching frit glass to the joining portion and heating to about 400 ° C. The fixing of the electron source substrate and the like on the rear plate is performed in the same manner.
As an actual operation, a heat treatment at about 300 ° C. is performed in the air to remove components contained as a binder in the frit glass (this step is referred to as “temporary firing”).
In an inert gas such as Ar,
A heat treatment at 0 ° C. is performed to weld the joint.

Subsequently, after the panel is connected to a vacuum exhaust system and the inside of the panel is sufficiently evacuated, the getter layer is activated.

In the following description of the present specification, the word “activation”, which indicates 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. Zr,
By diffusing the surface adsorbed atoms into the getter material by a method such as heating a non-evaporable getter mainly containing Ti or the like in a vacuum, a clean surface is formed, and the getter function is developed. To do. In the following, the term "getter activation" will be used for activating the getter material when necessary to avoid confusion.

In the present invention, it is preferable that the getter is activated by baking the evacuated panel. Therefore, the getter activation temperature is lower than the temperature at the time of sealing, for example, activation is performed at 300 ° C. to 350 ° C. for about 10 hours, but panel sealing is performed using a component which has been subjected to a vacuum heat treatment in advance. By doing so, the getter deterioration in the sealing step is suppressed, so that a sufficient getter effect can be obtained.

As described above, a wide getter area can be secured by forming a non-evaporable getter on a constituent member which has been subjected to a vacuum heat treatment in advance, especially on a rear plate or a face plate in an image display area. Moreover, it is possible to arrange the getter very close to the part where the gas is released most intensely with driving, and not only can the pressure inside the envelope of the image forming apparatus be kept low,
It is possible to realize an image forming apparatus in which the generated gas is quickly adsorbed on the getter, and the deterioration of the characteristics of the electron-emitting device and the fluctuation of the emission current are suppressed.

Next, NTS is performed by the above-described image forming apparatus.
An example of a configuration of a driving circuit for performing television display based on a C-system television signal will be described with reference to FIG. 3, reference numeral 31 denotes an image forming apparatus, 32 denotes a scanning circuit, 33 denotes a control circuit, 34 denotes a shift register, 35 denotes a line memory, 36 denotes a synchronizing signal separation circuit, 37 denotes a modulation signal generator, and Vx and Va denote DC voltages. Source.

[0064] Image forming apparatus (display panel) 31, terminal D _ox1 to D _oxm, connected to an external electric circuit via terminals D _Oy1 through D _Oyn and high voltage terminal Hv.

Terminals D _{ox1 to} D _oxm are connected to an electron source provided in the image forming apparatus 31, that is, a group of electron-emitting devices arranged in a matrix of m rows and n columns in one row (n elements). Scan signals for sequentially driving are applied one by one.

[0066] The terminal D _Oy1 to _D oyn, modulation signals for controlling the output electron beam of each of the electron-emitting devices of one row selected by a scan signal.

The high voltage terminal Hv is connected to a DC voltage source Va.
For example, a DC voltage of 10 kV is supplied, which is an accelerating voltage for applying sufficient energy to the electron beam emitted from the surface conduction electron-emitting device to excite the phosphor.

The scanning circuit 32 will be described. The circuit includes m switching elements (S1 to S
m is schematically shown). Each of the switching elements, the DC voltage source Vx of either the output voltage or 0V (ground level) is connected terminals D _ox1 to D _oxm and electrically the image forming apparatus 31. Each of the switching elements S1 to Sm includes a control circuit 3
3 operates based on the control signal T _SCAN output by the control signal 3 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 emits electrons based on the characteristics (electron emission threshold voltage) of a surface conduction electron-emitting device or the like, and the driving voltage applied to the unscanned device emits electrons. It is set to output a constant voltage that is equal to or lower than the threshold voltage.

The control circuit 33 has a function of matching the operation of each unit so that appropriate display is performed based on an image signal input from the outside. The control circuit 33 generates T _SCAN , T _SFT, and T _MRY control signals for each unit based on the synchronization signal T _SYNC sent from the synchronization signal separation circuit 36.

The synchronizing signal separation circuit 36 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 36 includes a vertical synchronizing signal and a horizontal synchronizing signal, but is shown here as a T _SYNC signal for convenience of explanation. The luminance signal component of the image separated from the television signal is represented as a DATA signal for convenience. This DATA signal is input to the shift register 34.

The shift register 34 is for serially / parallel-converting the DATA signal input serially in time series for each line of an image. The shift register 34 converts the DATA signal into a control signal T _SFT sent from the control circuit 33. (Ie, the control signal T _SFT may be a shift clock of the shift register 34). The data for one line of the serial / parallel-converted image (corresponding to the driving data for n electron-emitting devices) are I _{d1 to} I _dn.
Are output from the shift register 34 as n parallel signals.

The line memory 35 is a storage device for storing data for one line of an image for a required time only.
The contents of I _{d1 to} I _dn are appropriately stored according to the control signal T _MRY sent from the control circuit 33. The stored content is I
_d'1 to be output as I _d'n, it is input to the modulation signal generator 37.

The modulation signal generator 37 outputs the image data I _{d′ 1}
Or in response to each of the I _d'n, a signal source for appropriately driving modulating each of the electron-emitting device, the output signal, the electron-emitting device of the image forming apparatus 31 through the terminals D _Oy1 to D _Oyn Is applied to

As shown in the above-mentioned Japanese Patent Application Laid-Open No. 7-235255, the surface conduction electron-emitting device applicable as the electron source of the image forming apparatus of the present invention has the following emission current _Ie . Has basic characteristics. 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. Therefore, when a pulse-like voltage is applied to the device, 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. Outputs an electron beam. At that time, the intensity of the output electron beam can be controlled by changing the peak value Vm of the pulse. Further, by changing the pulse width Pw, it is possible to control the total amount of charges of the output electron beam.

Therefore, as a method of modulating the electron-emitting device according to the input signal, a voltage modulation method, a pulse width modulation method, or the like can be adopted. When implementing the voltage modulation method, the modulation signal generator 37 generates a voltage pulse of a fixed length, and a voltage modulation circuit capable of appropriately modulating the peak value of the voltage pulse according to input data. Can be used.

When implementing the pulse width modulation method,
As the modulation signal generator 37, 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 34 and the line memory 35
Can be adopted as a digital signal type or an analog signal type. 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 synchronization signal separation circuit 36 into a digital signal. For this purpose, an A / D converter is provided at the output of the synchronization signal separation circuit 36. Just do it. In connection with this, the circuit used for the modulation signal generator 37 is slightly different depending on whether the output signal of the line memory 35 is a digital signal or an analog signal. That is, in the case of the voltage modulation method using a digital signal, the modulation signal generator 37 includes, for example, D / D
An A conversion circuit is used, and an amplification circuit and the like are added as necessary. In the case of the pulse width modulation method, the modulation signal generator 37 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 amplifying the pulse width modulated signal output from the comparator to the drive voltage of the electron-emitting device can be added.

In the case of the voltage modulation method using an analog signal, for example, an amplification circuit using an operational amplifier or the like can be used as the modulation signal generator 37, and a level shift circuit or the like can be added as necessary. In the case of the pulse width modulation method, for example, a voltage controlled oscillator (VCO) can be employed, and an amplifier for amplifying the voltage up to the driving voltage of the electron-emitting device can be added as necessary.

[0081] In the image forming apparatus to which the present invention can be applied which can take such a construction, the respective electron-emitting devices, applying a voltage through the vessel terminals D _ox1 to _{D oxm,} D oy1 to D _Oyn As a result, electron emission occurs. A high voltage is applied to the metal back 16 or the transparent electrode (not shown) via the high voltage terminal Hv to accelerate the electron beam. The accelerated electrons collide with the fluorescent film 15 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. The input signal has been described in the NTSC system. However, the input signal is not limited to this. In addition to the PAL and SECAM systems,
A TV signal composed of more scanning lines than these (for example,
A high-definition TV system such as the MUSE system can also be adopted.

The image forming apparatus produced according to the present invention
In addition to a display device of a television broadcast, a display device such as a video conference system and a computer, the present invention can be used as an image forming device as an optical printer including a photosensitive drum or the like.

[0084]

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 is
It has a configuration similar to that of the device schematically shown in FIG. 1, and the getter layer is arranged in the boundary region of the phosphor of the face plate 13.

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

FIG. 4 is a plan view of the negative part of the electron source substrate 1. FIG. 5 is a sectional view taken along the line AA ′ in FIG. However, the same reference numerals in FIGS. 4 and 5 indicate the same components. Here, 3 is an X-direction wiring (also called a lower wiring), 4 is a Y-direction wiring (also called an upper wiring), 51 is a glass substrate, 52 is an interlayer insulating layer, 54 and 55 are device electrodes, and 56 is an electron emission portion. A conductive film 53 is a contact hole for electrical connection between the element electrode 54 and the lower wiring 3.

Hereinafter, a method for manufacturing the image forming apparatus of this embodiment will be described with reference to FIGS.

Step-a A 5 nm-thick Cr layer and a 600 nm-thick Au layer are successively deposited by vacuum evaporation on a substrate 51 having a 0.5 μm-thick silicon oxide film formed on a cleaned blue plate glass by a sputtering method. After that, a photoresist (AZ1370 / Hoechst) is spin-coated and baked by a spinner, and then a photomask image is exposed and developed to form a resist pattern of the lower wiring 3, and the Au / Cr deposited film is wet-etched. Then, the lower wiring 3 having a desired shape is formed (FIG. 6A).

Step-b Next, an interlayer insulating layer 52 made of a silicon oxide film having a thickness of 1.0 μm is deposited by RF sputtering (FIG. 6).
(B)).

Step-c A photoresist pattern for forming the contact hole 53 is formed in the silicon oxide film deposited in the step-b, and the interlayer insulating layer 52 is etched using the photoresist pattern as a mask to form the contact hole 53. Etching is CF
RIE (Reactive Io) using ₄ and H ₂ gas
n Etching) method (FIG. 6 (c)).

Step-d Thereafter, a pattern to be used as an element electrode is formed with a photoresist (RD-2000N-41 / manufactured by Hitachi Chemical Co., Ltd.).
5 nm thick Ti, 100 nm thick by vacuum evaporation
Of Ni were sequentially deposited. The photoresist pattern was dissolved in an organic solvent, and the Ni / Ti deposited film was lifted off. The device electrode gap G was 3 μm, the device electrode width was 300 μm, and the device electrodes 54 and 55 were formed (FIG. 6D).

Step-e After forming a photoresist pattern of the upper wiring 4 on the device electrodes 54, 54, a Ti having a thickness of 5 nm and a thickness of 500 nm are formed.
Are sequentially deposited by vacuum evaporation, and unnecessary portions are removed by lift-off to form an upper wiring 4 having a desired shape (FIG. 7E).

Then, the substrate obtained in the step-e was set to 1.3.
Heat treatment was performed at 480 ° C. for 1 hour in a vacuum device of × 10 ⁻⁴ Pa to degas from the substrate.

Step-f Next, a 100 nm-thick Cr film 57 is deposited and patterned by vacuum evaporation, and a solution of a Pd amine complex (ccp4230 / Okuno Pharmaceutical Co., Ltd.) is spin-coated thereon with a spinner, A heating and baking treatment was performed at 10 ° C. for 10 minutes. The thus formed conductive film 56 for forming an electron emitting portion composed of fine particles composed of Pd as a main element had a thickness of 8.5 nm and a sheet resistance of 3.9 × 10 ⁴ Ω / □. The fine particle film described here is a film in which a plurality of fine particles are aggregated, and has a fine structure not only in a state in which the fine particles are individually dispersed but also in a state in which the fine particles are adjacent to each other.
Alternatively, it refers to a film in an overlapping state (including an island shape). (FIG. 7 (f)).

Step-g Cr Film 57 and Conductive Film 5 for Forming Electron Emission Portion after Firing
6 was re-etched with an acid etchant to form a desired pattern (FIG. 7 (g)).

Step-h: A pattern is formed such that a resist is applied to portions other than the contact hole 53, and a 5 nm-thick T
i, Au having a thickness of 500 nm was sequentially deposited. Unnecessary portions were removed by lift-off to bury the contact holes 53 (FIG. 7H).

Through the above steps, a plurality of (1)
(00 rows × 300 columns) conductive film 56 for forming electron-emitting portions
Formed the electron source substrate 1 in which the upper wiring 4 and the lower wiring 3 were simply wired in a matrix.

Step-i Subsequently, the face plate 13 shown in FIG. 1 was manufactured as follows. A transparent conductive film (IT
O), and a fluorescent film 15 was formed thereon by a printing method. Note that the fluorescent film 15 was a fluorescent film shown in FIG. 2A in which stripe-shaped three primary color phosphors (R, G, B) 18 were sequentially arranged. Further, a metal back 16 made of an Al thin film is formed on the fluorescent film 15 by a sputtering method.
It was formed to a thickness of 0 nm.

Step-j Next, the face plate obtained in step-i was subjected to 1.3
Heat treatment was performed at 480 ° C. for 1 hour in a vacuum device of × 10 ⁻⁴ Pa to perform degassing. Subsequently, as shown in FIG. 11, a metal mask 112 having an opening 113 corresponding to each color boundary of the three primary color phosphors 18 which are separately applied is aligned and arranged, and Zr, Zr are formed in the reduced pressure plasma spraying apparatus.
A getter layer 19 was formed by vapor deposition of a getter material composed of V and Mn. After the spraying was completed, the substrate was sufficiently cooled, and nitrogen gas was introduced into the apparatus to stabilize the getter surface, thereby completing the production of the image forming substrate (face plate 13). The particle size of the getter layer obtained in this step is from 20 μm to 40 μm.
m, the average film thickness was about 80 μm.

Step-k Subsequently, the envelope 17 shown in FIG. 1 was manufactured as follows. After fixing the electron source substrate 1 manufactured by the above-described process to the rear plate 11 subjected to the vacuum heat treatment, the lower wiring 3 and the upper wiring of the electron source substrate 1 are combined with the support frame 12 and the face plate 13 subjected to the vacuum heat treatment. 4 was connected to the row selection terminal 5 and the signal input terminal 6, respectively, and the positions of the electron source substrate 1 and the face plate 13 were strictly adjusted and sealed to form an envelope 17. The sealing method is as follows: frit glass is applied to the joint of each member and calcined at 300 ° C. in the air.
A heat treatment for 0 minutes was performed to join. The electron source substrate 1 and the rear plate 11 were fixed in the same manner.

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

In FIG. 8, reference numeral 81 denotes an image display device in a manufacturing process, and reference numeral 83 denotes a vacuum chamber. An exhaust pipe 82 connects the image display device 81 and the vacuum chamber 83. The vacuum chamber 83 is provided with a gate valve 84.
, And the gate valve 84 is connected to an exhaust device 85. The exhaust device 85 is an ultra-high vacuum exhaust device including a sorption pump and an ion pump. The vacuum chamber 83 has a pressure gauge 86 for monitoring the internal pressure, and a quadrupole mass spectrometer (Q-mass) for monitoring the gas partial pressure inside the vacuum chamber 83.
87 are equipped. Since it is difficult to directly measure the pressure and the partial pressure in the envelope 17, the pressure and the partial pressure in the vacuum chamber 83 are measured, and these values are regarded as those in the envelope 17. Further, the vacuum chamber 83 is connected to an ampoule or the like in which the introduced substance source 89 is sealed, through a gas introduction amount control device 88 installed in the middle of the gas introduction line.
The introduction amount can be controlled by the gas introduction amount control device 88.
As the gas introduction amount control device 88, a needle valve, a mass flow controller, or the like is used according to the type, flow rate, and required control accuracy of the substance to be introduced. In this embodiment, acetone ((CH ₃ ) ₂ C
O) as a substance source 89 and a gas introduction amount control device 88
, A slow leak valve was used.

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

Step-1 The inside of the envelope 17 was evacuated, and the pressure was increased to 1.3 × 10 ⁻³ Pa.
In the following, the following forming process for forming an electron emitting portion was performed on the above-described conductive film 56 for forming a plurality of electron emitting portions arranged on the electron source substrate 1.

As shown in FIG. 9, the Y-direction wirings 4 are connected in common and connected to the ground. A control device 91 controls the pulse generator 92 and the line selection device 94. 93 is an ammeter. The X-directional wiring 3 by the line selecting device 94
, One line is selected, and a pulse voltage is applied to this.
In the forming process, one row (30 rows) is applied to the element row in the X direction.
0 elements). The waveform of the applied pulse is shown in FIG.
The peak value was gradually increased with a triangular pulse as shown in FIG. Pulse width T ₁ = 1 msec. , Pulse interval T
₂ = 1Omsec. 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. Resistance value is 3.3
When kΩ (1 MΩ per element) was exceeded, the forming of that row was terminated, and the processing of the next row was started. This was performed for all the rows, and the forming of all the conductive films (the conductive film 56 for forming the electron emission portions) was completed, and the electron emission portions were formed in each of the conductive films.

Step-m Acetone ((CH ₃ ) ₂ CO) is placed in the vacuum chamber 83.
And hydrogen H ₂ were introduced, and the partial pressure of each was changed to (CH ₃ ) ₂ C
O); 1.3 × 10 ⁻³ Pa, H ₂ ; 1.3 × 10 ⁻² Pa
Then, a pulse was applied to the electron source while measuring the device current _If to activate each electron-emitting device. The pulse waveform generated by the pulse generator 92 is the rectangular wave shown in FIG. 10B, with a peak value of 14 V and a pulse width T ₁ = 100 μsec. , Pulse interval is 167μ
sec. It is. 167μ by the line selection device 94
sec. The selection line is sequentially switched from D _x1 to D _x100 every time, and as a result, T ₁ = 100 μs
c. , T ₂ = 16.7 msec. Is applied with a slightly shifted phase for each row.

The ammeter 93 is used in a mode for detecting the average of the current value in the ON state of the rectangular 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 17 was evacuated.

Step-n While continuing the evacuation, the entire image display device 81 and the vacuum chamber 83 were heated to 300 ° C. by a heating device (not shown).
For 24 hours. This process removes (CH ₃ ) ₂ CO and its decomposition products, which are presumably adsorbed on the envelope 17 and the inner wall of the vacuum chamber 83, and activates the non-evaporable getter formed on the face plate 17. Was done.

Step-o After confirming that the pressure is 1.3 × 10 ⁻⁵ Pa or less, the exhaust pipe 82 is heated with a burner and sealed off.

Thus, the image forming apparatus of this embodiment was manufactured.

[Embodiment 2] In this embodiment, the getter material is made of T
This shows an example in which a getter layer is formed on an upper wiring on an electron source substrate using i and Al. As in the case of Example 1, all the components used were those subjected to a vacuum heat treatment in advance.

First, after performing the steps up to step-i in the same manner as in the first embodiment, the electron source substrate 1 is formed using the same method as in the first embodiment.
A getter thin film was formed on the upper wiring 4 to a thickness of 50 μm by plasma spraying. The composition of the powder used was Ti85w
The alloy is t%, Al 15 wt%.

Next, the electron source substrate, the face plate and the like obtained in the above steps were welded with a glass frit in an argon atmosphere to form a panel.

Further, the produced panel is connected to a high-vacuum exhaust device constituted by a rotary pump and a turbo pump as an exhaust device 85 of the vacuum processing device shown in FIG. The pressure of 1.3 × 10 ⁻⁴ Pa or less is set, and the activation treatment is performed in the same manner as in the process 1 of the first embodiment.
The same pulse as in m was applied.

The activation process is performed in the vacuum chamber 8
No particular gas is introduced into the exhaust device 3
This was performed by depositing carbon using an organic substance slightly remaining in the vacuum chamber 83 due to diffusion from 5. At this time, the pressure in the vacuum chamber 83 is 2.7.
It was about × 10 ⁻³ Pa.

After the activation was completed, the device current _If and the emission current _Ie were measured by applying 16 V, and the average value per device was _If = 2.2 mA and _Ie = 2. 2 μA
It was.

Subsequently, while the entire panel is evacuated, 3
Baking was performed at 00 ° C. for 24 hours, and the getter was activated together with evacuation of the inside of the panel.

Finally, the exhaust pipe was heated with a burner and sealed off in the same manner as in Step-o of Example 1, thereby producing an image forming apparatus of this example.

[0120]

As described above, according to the present invention, an image forming apparatus including a non-evaporable getter is manufactured by using a constituent member which has been subjected to a vacuum heat treatment in advance, thereby reducing getter deterioration during panel manufacturing. Not only can provide a method of manufacturing an image forming apparatus, but also can suppress deterioration of the characteristics of the electron-emitting device,
As a result, it is possible to provide an image forming apparatus in which the luminance does not decrease when the device is operated for a long time, and particularly, the luminance does not decrease near the center of the image display area.

Although the embodiment shows the image forming apparatus using the surface conduction electron-emitting device, the same effect can be obtained when the present invention is applied to an image forming apparatus using a so-called plasma display panel. Is expected of course.

[Brief description of the drawings]

FIG. 1 is a partially broken perspective view showing a structural example of an envelope of an image forming apparatus produced by a manufacturing method of the present invention.

FIG. 2 is a diagram for explaining a structure of a fluorescent film.

FIG. 3 is a block diagram illustrating a configuration example of a drive circuit for performing television display based on an NTSC television signal by an image forming apparatus configured using an electron source arranged in a matrix.

FIG. 4 is a plan view schematically showing an electron source substrate having a matrix arrangement according to an example.

FIG. 5 is a cross-sectional view of the electron source substrate taken along line AA ′ of FIG. 4;

FIG. 6 is a diagram for explaining a manufacturing process of the electron source substrate shown in FIG.

FIG. 7 is a diagram for explaining a manufacturing process of the electron source substrate shown in FIG.

FIG. 8 is a schematic diagram illustrating an outline of a vacuum processing apparatus used for manufacturing an image forming apparatus.

FIG. 9 is a schematic diagram illustrating a configuration of an apparatus used for a manufacturing process, a forming process, and an activation process of the image forming apparatus.

FIG. 10 is a diagram illustrating an example of a pulse voltage waveform applied to a forming process and an activation process.

FIG. 11 is a diagram for explaining a method of forming a getter layer in an example.

FIG. 12 is a cross-sectional view of a part related to getter processing in a conventional flat plate image forming apparatus.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electron source substrate 2 electron-emitting device 3 X-direction wiring (lower wiring) 4 Y-direction wiring (upper wiring) 5 row selection terminal 6 signal input terminal 11 rear plate 12 support frame 13 face plate 14 glass substrate 15 fluorescent film 16 metal Back 17 Enclosure 18 Phosphor 19 Getter layer 31 Display panel 32 Scan circuit 33 Control circuit 34 Shift register 35 Line memory 36 Synchronous signal separation circuit 37 Modulation signal generator 51 Glass substrate 52 Interlayer insulating layer 53 Contact hole 54, 55 element Electrode 56 Conductive film for forming electron-emitting portion 57 Cr film 81 Image display device during manufacturing process 82 Exhaust pipe 83 Vacuum chamber 84 Gate valve 85 Exhaust device 86 Pressure gauge 87 Q-mass 88 Gas introduction amount control device 89 Introduced substance Source 91 Controller 92 Pulse generator 93 Current Total 94 Line selection device 111 Transparent conductive film 112 Metal mask 113 Metal mask opening 114 Sprayed particles

Claims (12)

[Claims] 1. A method for manufacturing an image forming apparatus including at least a non-evaporable getter in an envelope, wherein each component is heated to a sealing temperature or higher in a vacuum before a sealing step of the envelope. A method of manufacturing an image forming apparatus, comprising: 2. The method for manufacturing an image forming apparatus according to claim 1, wherein the sealing of the envelope is melting and bonding using a low melting point glass frit. 3. The image forming apparatus according to claim 1, further comprising, in an envelope, an electron source substrate on which a plurality of electron-emitting devices are provided, and an image forming substrate on which an image forming member is provided. A method for manufacturing an image forming apparatus according to claim 1. 4. The method according to claim 3, wherein the electron-emitting device is a surface conduction electron-emitting device. 5. The method according to claim 3, wherein the non-evaporable getter is formed on a surface of the electron source substrate. 6. The method according to claim 5, wherein the formation of the non-evaporable getter is performed after the electron source substrate is heated in a vacuum at a sealing temperature or higher. Method. 7. The method according to claim 3, wherein the non-evaporable getter is formed on a surface of the image forming substrate. 8. The method according to claim 7, wherein the formation of the non-evaporable getter is performed after the image forming substrate is heated in a vacuum at a sealing temperature or higher. Method. 9. The material of the non-evaporable getter contains Ti or / and Zr as a main component and further contains Al, V, Fe,
The method of manufacturing an image forming apparatus according to claim 1, wherein the alloy is an alloy containing any one or more of Mn as a subcomponent. 10. The activation of the non-evaporable getter is performed by a heat treatment in a baking step of performing a heat treatment while evacuating the envelope after sealing the envelope. A method for manufacturing an image forming apparatus according to claim 1. 11. The activation temperature of the non-evaporable getter is:
The method according to claim 10, wherein the temperature is lower than a sealing temperature of the envelope. 12. The image forming apparatus according to claim 1, wherein a light-emitting medium is sealed in an envelope in which a front substrate and a rear substrate each having a display electrode and an auxiliary electrode formed on at least one of the substrates are arranged opposite to each other. 3. The method according to claim 1, wherein the image forming apparatus is configured to perform display by applying a voltage to the display electrode and the auxiliary electrode. 4.