JP2000231880A - Forming method of non-evaporation type getter, image forming device using same non-evaporation type getter, and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device undergoing less change in brightness with lapse of time (less deterioration in brightness with lapse of time) and provide an image forming device undergoing less variation in brightness in an image forming region with lapse of time, by disposing a getter film of large capacity and of a large surface area in a display region of the image forming device by employing a structure suitable for mass production and a method of low-cost manufacturing. SOLUTION: As a mask 5 for thermal spraying used to screen parts other than a formed part of a getter 11 formed by a thermal spraying method from a thermal spraying source, a mask 5 provided with a separation film 7 is used to facilitate the recycling of the mask 5 by removing a getter material 10 deposited on the mask 5. This method has a process for forming the getter 11 by using the mask 5 and a process for collecting the getter material 10 deposited on a surface of the mask 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method of forming a non-evaporable getter, an image forming apparatus using the non-evaporable getter, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus which irradiates an electron beam emitted from an electron source to a phosphor as an image display member and causes the phosphor to emit light to display an image, an electron source and an image forming member are used. Must be kept at a high vacuum inside the sealed vacuum vessel containing the vacuum vessel. That is, when gas is generated inside the vacuum vessel and the pressure rises, the degree of the effect varies depending 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 an electron beam to become ions, which are accelerated by an electric field for accelerating the electrons and collide with the electron source, thereby damaging the electron source. Additionally, in some cases,
In some cases, a discharge is generated inside the electron source, which may destroy the device.

[0004] The adverse effect on the electron source due to the deterioration of the vacuum becomes more serious especially in a flat display using an electron source in which a large number of electron-emitting devices are arranged on a flat substrate.

As a proposal for solving the above-mentioned problem in the image forming apparatus, a method of forming a getter surface by an evaporable getter between an image forming member outside the display area of the image forming apparatus and the electron source substrate is proposed. (JP-A-5-15191
No. 6) and a method of increasing the volume of a getter by providing a groove on the inner surface of an image forming member around an image display section (fluorescent screen) and embedding a non-evaporable getter in the groove (Japanese Patent Application Laid-Open No. HEI 5 (1993) -107). −
No. 121015).

However, when the above-described methods are used, the arrangement position of the getter material is limited. Further, the problem of vacuum deterioration in a vacuum vessel in a flat plate image forming apparatus includes:
In addition to the above-mentioned problems, there is a problem that the pressure tends to increase locally. In an image forming apparatus having an electron source and an image display member, a portion for generating a gas in a vacuum vessel is:
The image display area mainly irradiated by the electron beam and the electron source itself. 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, so that the gas generated by the image display member reaches the electron source. The pressure does not increase so much when it reaches the electron source by being partially absorbed by the getter film. Further, since there is a getter film around the electron source itself, an extreme 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 display member and the electron source are close to each other, the gas generated from the image display member reaches the electron source before being sufficiently diffused, and the local pressure increases. Bring rise.

Particularly, in the central part of the image display area, since gas cannot diffuse to the area where the getter film is formed, it is considered that a local pressure rise is larger than that in the peripheral part. The generated gas is ionized by the electrons emitted from the electron source and accelerated by the magnetic field formed between the electron source and the image display member, damaging the electron source or causing a discharge to destroy the electron source. Or you may.

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 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 type electron source having a conical projection as a cathode, and a pn junction. Are exemplified. This gate electrode is made of Ta, Zr,
It is made of an alloy such as Ti, Th, and Hf, and is formed by a semiconductor process.

In Japanese Patent Application Laid-Open No. Hei 8-2278, an electron source flat display device comprising a large number of field emission cathodes relates to an inner wall surface between phosphors of a front side panel having phosphors or an electron source. On the wall surface between the cathode groups, an evaporable getter such as a Ba film made of BaAl ₄ of about 100 nm as a raw material is formed by a mask evaporation method.

Japanese Patent Application Laid-Open No. 63-181248 and Japanese Patent Publication No. 6-3714 disclose a cathode (cathode).
A method of forming a film of a getter material on a control electrode in a flat display having a structure in which an electrode (eg, a grid) for controlling an electron beam is arranged between the group and a face plate of a vacuum vessel. It has been disclosed. In the example of Japanese Patent Application Laid-Open No. 63-181248, the getter material is Zr.
(84%)-Al (16%), and is formed directly on the electrode by a vacuum deposition method, a sputtering method, an ion plating method, a coating method, or the like. 6-37
In the example of Japanese Patent Application Publication No. 14, a small piece obtained by pressing a getter material on a metal plate having a thickness of 0.1 mm (for example, St.
707 is fixed on the electrode by spot welding.

Also, US Pat. No. 5,453,659, “Anode Plate for Flat P
anel Display having Inter
graded Getter ”, issue 26
Sept. 1995, to Wallace et a
l. Discloses a method in which a getter member is formed in a gap between phosphors on a stripe on an image display member (anode plate). In this example, the getter material is. Zr
Forming a film of V.Fe or Ba to a thickness of 0.1 to 1 μm by ion beam sputtering or electron beam evaporation,
After that, it is shaped by lithography.

The getter material is electrically separated from the phosphor and a conductor electrically connected to the phosphor. The getter material is given an appropriate potential to the getter to irradiate and heat the electrons emitted from the electron source. Activating the getter, or activating the getter by energizing and heating the getter.

It is needless to say that an electron-emitting device constituting the electron source used in the 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.

[0015] In this respect, the above-mentioned Japanese Patent Application Laid-Open No. Hei 4-12436 has been disclosed.
Source disclosed in Japanese Unexamined Patent Application Publication No. H8-27139, and an inner wall surface between phosphors of a front panel or each cathode group of an electron source disclosed in Japanese Patent Application Laid-Open No. H8-2278. For electron source flat display devices consisting of a large number of field emission cathodes having an evaporation type getter deposited film on the wall between them, in the manufacture of conical cathode tips or in the manufacture of semiconductor junctions, etc. Requires a complicated process. Further, there is a limit to the size of the image forming apparatus due to the manufacturing apparatus.

Also, JP-A-63-181248,
And JP-B-6-3714,
In a device in which a control electrode or the like is provided between the electron source and the face plate, the structure becomes complicated, and a complicated process such as alignment of these members is involved in a manufacturing process.
As disclosed in U.S. Pat. No. 5,453,659, a method of forming a getter material on an anode plate comprises:
It is necessary to provide electrical insulation between the getter material and the phosphor, and it is formed by repeatedly performing patterning by photolithography technology for precise fine processing. Therefore, the process becomes complicated, and the size of the image forming apparatus that can be manufactured is limited by the size of the apparatus used for photolithography.

Examples of the electron-emitting device having a structure capable of satisfying the above-mentioned requirement that the manufacturing process is easy include a horizontal field-emission electron-emitting device and a surface conduction electron-emitting device.

The horizontal field emission type electron-emitting device has a cathode having a sharp electron emission portion on a flat substrate;
It is formed by facing an anode (gate) for applying a high electric field to a cathode, and can be manufactured by a thin film deposition method such as vapor deposition, sputtering, plating, or the like, and ordinary photolithography technology. The surface conduction electron-emitting device emits electrons when a current is applied to a conductive thin film having a high resistance part in a part thereof, and is disclosed in JP-A-7-235255 by the present applicant. One example is shown.

In an image forming apparatus using these elements, a method of arranging a getter material effectively in an image display area and activating the getter material has been proposed in Japanese Patent Application Laid-Open No. 9-8224.
No. 5 discloses this. In this example, the getter material is
It is made of an alloy containing at least one of Ti and Zr as a main component or an alloy containing at least one of Al, V, and Fe as a subcomponent. The getter material is formed by a vacuum evaporation method or a sputtering method.

[0020]

By the way, in order to adsorb and exhaust gas molecules in a container for a long period of time, it is necessary to increase the volume and the surface area of the getter film itself. However, since the method of forming the getter material in the above proposal is formed by a vacuum deposition method, a sputtering method, or the like, the film thickness of the getter material that can be formed in one process is determined in consideration of the film formation speed at the time of film formation. The upper limit is at most several μm. In order to form a getter material having a larger film thickness by the same method, an increase in the time required for film formation is unavoidable, leading to an increase in cost.

The surface area of a film formed by the same method can be controlled somewhat depending on the film forming conditions at the time of vapor deposition. However, in order to form a film having a larger surface area, the surface shape of an object to be vapor-deposited must be adjusted. Special processes such as processing are required.

According to the present invention, with a configuration suitable for mass production and a low-cost manufacturing method, a large-capacity, large-area getter film is arranged in the display area of the image forming apparatus, and the luminance changes over time (temporal change). It is an object of the present invention to provide an image forming apparatus with little (decrease) and to provide an image forming apparatus with less variation in luminance over time in an image forming area.

[0023]

Means for Solving the Problems The present invention made to achieve the above object has the following features.

That is, a method of forming a non-evaporable getter according to the present invention is directed to an image forming method comprising: an electron source having a plurality of electron-emitting devices disposed on a substrate; and an image forming member disposed to face the substrate. A method for forming a non-evaporable getter in an image display area of an apparatus, wherein the non-evaporable getter is attached to the mask as a thermal spraying mask used to shield a portion other than a getter forming portion formed by a thermal spraying method from a thermal spraying source. Using a mask provided with a separation film for removing the getter material and facilitating reuse of the mask, forming a getter using the mask, and collecting getter material attached to the mask surface And characterized in that:

Further, the non-evaporable getter may be formed on a wiring for applying a voltage to the electron-emitting device arranged on the electron source substrate, or a fluorescent light on the image forming member may be formed. It may be formed on a black material separating the body region via a metal back. Preferably, the separation film formed on the mask surface is a heat-resistant polymer film or a metal thin film.

Further, the thermal decomposition temperature of the heat-resistant polymer film is preferably 300 ° C. or higher.

Preferably, the metal thin film is an aluminum thin film.

Preferably, the mask is made of an Fe-based alloy or a ceramic.

As a method of removing and collecting the getter material adhered to the mask surface, the method includes a step of heating the mask to a temperature higher than the decomposition temperature of the separation membrane and lower than the melting temperature of the mask and the getter material. Alternatively, it is preferable to include a step of immersing the mask in a solution capable of dissolving the separation membrane.

Preferably, the getter material is Ti, Zr, or an alloy containing at least one of them as a main component.

The thickness of the getter is 10 to 100.
μm is preferred.

A method of manufacturing an image forming apparatus according to the present invention is characterized in that a plurality of electron sources arranged in a matrix are arranged on a substrate, and a non-evaporable getter is formed by one of the above-mentioned methods. Is what you do.

Further, a method of manufacturing an image forming apparatus according to the present invention includes an electron source having a surface conduction electron-emitting device, and a non-evaporable getter formed by any of the above-described methods. It is.

An image forming apparatus according to the present invention includes an electron source having a horizontal field emission type electron-emitting device and a non-evaporable getter formed by any of the above-described methods. .

Further, an image forming apparatus according to the present invention includes a non-evaporable getter formed by any of the above-described methods.

According to the image forming apparatus using the non-evaporable getter formed by the method of forming a non-evaporable getter of the present invention, by disposing the non-evaporable getter in the image display area, the image display as a gas emission source can be performed. The gas generated from the region can be exhausted quickly and for a long time. As a result, it is possible to suppress the deterioration of the electron-emitting device and the fluctuation of the emission current amount.

Therefore, as a result, it is possible to suppress a decrease in luminance when the image forming apparatus is operated for a long time, especially a decrease in luminance near the center of the image display area.

Further, by collecting the getter material adhered on the thermal spray mask, not only can the thermal spray material be used again, but also the mask can be used repeatedly, so that the manufacturing cost can be reduced.

[0039]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to preferred embodiments of the present invention.

A first example of a preferred embodiment of the present invention is a method of forming a non-evaporable getter by a thermal spraying method on a wiring for applying a voltage to an electron-emitting device arranged on an electron source substrate. At this time, the method includes a step of collecting the getter material adhered to the surface on the mask arranged to prevent the getter material from adhering to portions other than the wiring portion.

FIG. 1 schematically shows an example of a method of manufacturing an image forming apparatus according to the present invention. Using FIG.
A method for forming a getter on a wiring and a method for collecting a getter on a mask surface will be described.

FIG. 1A shows an electron source substrate 1 on which a plurality of electron-emitting devices 4, suitable X-direction wirings 2 and Y-direction wirings 3 are formed. In forming a getter on a part of the Y-direction wiring 3, a mask 5 shown in FIG. 1B is used to shield portions other than the formation portion from a thermal spraying source.

The ratio of the area where the getter is formed is usually
Since it is less than 20% of the entire substrate, most of the sprayed getter material adheres to the mask. If these getter materials can be collected and used again as a thermal spraying material, the effect is large in terms of cost reduction.

As the mask substrate, an iron-nickel alloy is preferably used because it has excellent heat resistance and a small coefficient of thermal expansion. However, if this is used as it is, the getter material is fused to the mask substrate 6. Therefore, it is not easy to separate them later. Mask 5 used a certain number of times
Must be discarded with the getter attached.

Therefore, in the present invention, the mask substrate 6
A method has been proposed in which the getter material can be easily collected and reused, and the mask substrate 6 can also be reused. That is, in the present invention, the mask 5 is composed of the mask base material 6 and the separation film 7 formed on the surface of the mask base material, and is provided with an opening conforming to the shape of the getter to be formed. The separation film 7 is formed to prevent fusion between the mask 5 and the getter material and to facilitate removal and collection of the getter.

As the mask base material 6 used in the present invention, iron-nickel alloy is preferably used because of its excellent heat resistance and small coefficient of thermal expansion. A metal steel plate such as an iron / nickel alloy plate, a glass plate, a ceramic plate, or the like can also be used.

Further, the separation film 7 formed on the mask 5 has resistance to a rise in temperature during welding, and furthermore, the mask base material 6 and the getter material are deteriorated in the step of separating and collecting the getter material described later. It is desired that the film be capable of being thermally decomposed or dissolved under conditions that do not cause the decomposition.

The mask surface temperature at the time of welding is 200 to 2
Since it has been confirmed that the temperature has reached 50 ° C., it is desirable that the separation temperature of the separation membrane 7 is 300 ° C. or higher, for example, a fluorine-based resin, a polyimide resin, an epoxy resin, a phenol resin, and polyvinyl alcohol. A polymer coating such as a resin may be used. Methods for forming a coating on the mask surface include electrodeposition coating, spraying, dipping,
A method such as spin coating can be used.

Although it is possible to use a metal and metal compound coating, an aluminum thin film is a preferable material in consideration of a later step of separating and collecting the getter material.

As a film forming method, a method such as a sputtering method, a spray method, and plating can be used. The thickness of the separation membrane is not particularly limited, but is usually 10 to 50 μm.

As shown in FIG. 1C, the mask 5 is placed on the electron source substrate 1 with the alignment film formation surface facing upward and being sufficiently aligned. In addition, in order to more reliably shield the area other than the getter formation section, it is also possible to form a resist film 8 other than the wiring section by a photoresist process, or use a means for bonding the electron source substrate 1 and the mask 5. It is.

As shown in FIG. 1D, a getter material 10 is sprayed from the thermal spraying device 9 toward the masked electron source substrate 1 to form a getter on the wiring. The electron source substrate 1 and the mask 5 are separated.

The electron source substrate 1 on which the getter 11 is formed (FIG. 1E) is then combined with a support frame, a face plate and the like to form an image forming apparatus.

On the other hand, as a method of separating and collecting the getter material 10 from the mask surface after thermal spraying, a method of separating the two by removing the separation film 7 formed on the surface of the mask 5 can be used. To remove the separation membrane 7,
Baking at a temperature equal to or higher than the decomposition temperature of the separation membrane 7 and equal to or lower than the melting temperature of the mask 5 and the getter material 10, or a suitable solvent having no solubility in the mask base material 6 and the getter material 10 and capable of dissolving only the separation membrane 7 , A method of dissolving the separation membrane 7 can be used.

Getter material 10 separated from mask substrate 6
Is recovered by an appropriate method and used again as a thermal spray material (FIGS. 1 (f) and 1 (g)).

As the getter material 10 used for thermal spraying, a commonly used non-evaporable getter material can be used. For example, Ti, Zr, Hf, V, Nb, T
Metals such as a and W and alloys thereof can be used. Further, the alloy may contain Fe, Ni, Mn, or the like.

As the thickness of the getter film formed on the wiring, the lower limit of the particle size of the powder material is required in order to maintain the exhaust capability for a long time and to maintain the getter capability of the raw material powder and facilitate handling. The film thickness after thermal spraying is also determined, and a film thickness of about 10 μm or more is preferable. Also, in order to prevent film peeling after thermal spraying, the thickness of the getter film is
It is preferably 100 μm or less.

The surface of the sprayed film of the getter 11 is several μm.
Since it has irregularities of up to several tens of μm, it has a larger surface area than the surface of a vapor-deposited film vacuum-deposited on a smooth surface, and thus can have a higher pumping speed.

Further, a film having a thickness of about 10 to 100 μm can be easily formed in a short time by one thermal spraying, and the life of the getter 11 can be extended by forming such a thick film. it can.

FIG. 2 schematically shows a part of the configuration of the image forming apparatus according to the present invention, and has a configuration using the electron source substrate 1 manufactured by the method of FIG.

In FIG. 2, reference numeral 1 denotes an electron source substrate on which an X-directional wiring 2, a Y-directional wiring 3, an electron-emitting device 4, and a non-evaporable getter 11 are arranged. Reference numeral 13 denotes a support frame, and reference numeral 14 denotes a face plate. At the joint portion, they are adhered to each other using frit glass or the like to form an envelope 15.

The face plate 14 is made of a glass substrate 16
A fluorescent film 17 and a metal back 18 are formed thereon, and this portion becomes an image display area. In the case of a display device for displaying a black-and-white image, the fluorescent film 17 is made of only a phosphor,
When a color image is displayed, image forming units (hereinafter, also referred to as pixels) are formed by phosphors of three primary colors of red, green, and blue.
May be formed, and the space between them may be separated by a black conductive material. The black conductive material is called a black stripe, a black matrix, or the like, depending on its shape. The metal back 18 is formed of a conductive thin film of Al or the like. The metal back 18 reflects the light traveling toward the electron source 1 out of the light generated from the phosphor toward the glass base 16 to improve the brightness, and the gas remaining in the envelope 15 reduces the electron beam. The ions also generate ions, which also serve to prevent the phosphor from being damaged by the impact of the ions. Further, by giving conductivity to the image display area of the face plate 14 to prevent charge from being accumulated,
It functions as an anode electrode for the electron source 1.
The metal back 18 is electrically connected to the high voltage terminal Hv so that a voltage can be applied from outside the envelope 15 through the high voltage terminal Hv.

Reference numeral 20 denotes a row selection terminal for selecting a row of elements to emit electrons, and reference numeral 21 denotes a signal input terminal for inputting a signal for controlling the electron emission amount of the electron emission elements belonging to the selected row. It is.

The row selection terminal 20 is connected to the X in the electron source.
The signal input terminal 21 is connected to the Y-directional wiring 3. The form of these terminals is appropriately selected depending on the structure of the electron source 1 and the control method, and is not limited to the structure shown in FIG.

In some cases, an evaporable getter 12 (in the figure, a ring-shaped getter is schematically shown) is disposed in the envelope 15 as an auxiliary pump for keeping the interior of the envelope 15 vacuum. In this case, getter material scatters in the image display territory,
In order to prevent an electrical short circuit between the electrodes, a shield 19 is provided between the evaporable getter 12 and a region including the electron-emitting device 4, the wiring groups 2 and 3, and the anode electrode. In addition, when the inside of the envelope 15 can be sufficiently maintained in a vacuum by only the non-evaporable getter 11, the evaporable getter 12 and the shield 19 need not be formed.

The face plate 14 formed as described above, the support frame 13 and the electron source 1 and other structures are combined, and the support frame 13, the face plate 14 and the electron source 1 are joined. When the substrate of the electron source 1 alone cannot withstand the atmospheric pressure after evacuation, a spacer is disposed between the electron source 1 and the face plate 14 or a reinforcing plate is provided on the back surface of the electron source 1. You may combine and join. For joining, attach frit glass to the joint, 400 ° C
Heat to about the level. As the actual operation, 3
A heat treatment at about 00 ° C. is performed to remove components contained as a binder in the frit glass (this step is referred to as “temporary firing”).
) And an inert gas such as Ar (inert g).
As), a heat treatment at 400 ° C. is performed to weld the joint.

After that, when the electron source 1 includes a surface conduction electron-emitting device, necessary processing such as forming and activation of the electron-emitting device is performed, and the inside of the envelope 15 is sufficiently evacuated. After heating the entire envelope 15 at a high temperature of about 350 ° C. for several hours to several tens of hours to activate the non-evaporable getter 11 on the getter structure, the exhaust pipe (not shown) is heated by a burner. And seal off.

Lastly, if necessary, the evaporative getter 12 (in the figure, a ring-shaped getter is schematically shown) provided in the envelope 15 is heated, and the getter material is attached to the inner wall of the envelope 15. Is deposited to form a getter material film. The getter film thus formed is located outside the image display area in the envelope 15.

In a second example of the preferred embodiment of the present invention, the non-evaporable getter 11 is formed on the face plate 14 on a black material for separating the phosphor region via the metal back 18.

The structure of the fluorescent film 17 will be described with reference to FIG. FIG. 3A shows a case where the phosphors 23 are arranged in a stripe shape, and the phosphors 23 of three primary colors of red (R), green (G), and blue (B) are formed in order, and between them. Are separated by a black conductive material 22. In this case, the portion of the black conductive material 22 is called a black stripe.
FIG. 3B shows the dots of the phosphors 23 arranged in a grid pattern, which are separated by the black conductive material 22. In this case, the black conductive material 22 is called a black matrix.

As a method of patterning the black conductive material 22 and the phosphor 23 on the glass substrate 16, a slurry method, a printing method, or the like can be used. After the fluorescent film 17 is formed, a metal film such as Al is further formed to be a metal back 18.
A getter layer is further formed thereon. In this embodiment, the non-evaporable getter 11 is selectively formed on the black stripe or the black matrix 22 of the fluorescent film 17 via the metal back 18. The formation method is the same as the method described in the first embodiment, and thermal spraying is performed while masking a portion other than the black stripe or the black matrix portion with the mask 5.

Incidentally, the mask base material 6, the separation film 7 on the mask surface, and the getter material 10 preferably used in this embodiment are used.
Are the same as those described in the first embodiment. Separation and collection of the getter material 10 attached to the mask 5 can be performed in the same manner as in the first embodiment.

Further, the configuration and manufacturing method of the entire image forming apparatus are the same as those of the first embodiment except that the position of the non-evaporable getter 11 is different.
As described above, the non-evaporable getter having a thickness of about 10 to 100 μm and an uneven surface of several μm to several tens μm, formed by a plasma spraying method or the like, is used as an electronic device. By arranging in the image display area on the source substrate 1 or the face plate 14, the getter 11 having a large pumping speed and a total pumping amount allows
Gas generated from the image display area serving as a gas emission source can be quickly and long-term exhausted. This makes it possible to suppress deterioration of the electron-emitting device 4 and fluctuation of the emission current amount.

In FIGS. 1 and 2, a surface conduction electron-emitting device is shown as the electron-emitting device 4. However, the present invention is not limited to this, and a horizontal field emission electron-emitting device or the like may be used. Can be.

Next, NTS is performed by the above-described image forming apparatus.
An example of a structure of a driving circuit for performing television display based on a C-system television signal will be described with reference to FIG. 4, reference numeral 41 denotes an image forming apparatus (also referred to as a display panel) of the present invention, 42 denotes a scanning circuit, 43 denotes a control circuit,
44 is a shift register. Also, 45 is a line memory, 46 is a synchronization signal separation circuit, 47 is a modulation signal generator,
Vx and Va are DC voltage sources.

The image forming apparatus 41 has terminals _{Dox1 to Dox1
oxm} , terminals _{Doy1 to Doyn} , and a high voltage terminal Hv are connected to an external electric circuit. Terminals D _{ox1 -D
oxm} is a scanning device for sequentially driving 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 at a time (n elements). A signal is applied.

A modulation signal for controlling the output electron beam of each element of the one row of surface conduction electron-emitting devices selected by the scanning signal is _applied to the terminals _{Doy1 to Doyn} . The high-voltage terminal Hv is connected to the DC voltage source Va, for example, by one.
A DC voltage of 0 kV is supplied, which is an accelerating voltage for applying sufficient energy to an electron beam emitted from the surface conduction electron-emitting device to excite the phosphor.

Next, the scanning circuit 42 will be described. The scanning circuit 42 includes m switching elements inside (in the drawing, schematically shown by S _{1 to} S _m ). 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 D _{ox1 to} D _oxm of the image forming apparatus 41. Each of the switching elements S _{1 to} S _m operates based on the control signal T _scan 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 supplies a drive voltage applied to an unscanned element based on the characteristics (electron emission threshold voltage) of the surface conduction electron-emitting element. It is set so as to output a constant voltage lower than the emission threshold voltage.

The control circuit 43 has a function of matching the operation of each section so that an appropriate display is performed based on an image signal input from the outside. Control circuit 43 in accordance with the synchronization signal T _sync sent from the synchronous signal separation circuit 46, T _scan, T _sft, generates a respective control signal T _mry to each unit.

The synchronizing signal separation path 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. This DATA signal is input to the shift register 44.

The shift register 44 converts the DATA signal input serially in time series into a serial / parallel format for each line of an image. The shift register 44 converts the DATA signal into a control signal _Tsft sent from the control circuit 43. operates based (i.e., the control signal T _{sf t,} the shift register 44
Shift clock). The data for one line of the serial / parallel-converted image (corresponding to the drive data for n electron-emitting devices) are I _{d1 to} I _dn
Are output from the shift register 44 as n parallel signals.

The line memory 45 is a storage device for storing data for one line of an image for a required time only. According to a control signal T _mry sent from the control circuit 43, the contents of I _{d1 to} I _dn are appropriately determined. Is recorded. The stored contents are output as I _{d′ 1 to} I _{d′ n} and input to the modulation signal generator 47.

The modulation signal generator 47 outputs the image data I _{d′ 1}
To I _d'n , which is a signal source for appropriately driving and modulating each of the surface conduction electron-emitting devices, and an output signal of which is _transmitted through terminals _{Doy1 to Doyn} to the image forming apparatus 4.
1 is applied to the surface conduction electron-emitting device.

As described above, 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 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 this time, the intensity of the output electron beam can be controlled by changing the pulse peak value _Vpm . Also,
It is possible to control the total amount of electric charge of an electron beam output by changing the width P _w of pulse.

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
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 46 into a digital signal.
What is necessary is just to provide a D converter. In this connection, 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, the modulation signal generator 47 includes, for example, D
A / 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 4
For example, a circuit that combines a high-speed oscillator, a counter that counts the number of waves output by the oscillator, and a comparator that compares the output value of the counter with the output value of the memory is used as the reference numeral 7. 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 necessary. . 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 take such a configuration, each of the electron-emitting devices is provided with a terminal D outside the container.
_ox1 to D _oxm, by applying a voltage via the _D oy1 ~D oyn, electron emission occurs. A high voltage is applied to the metal back 18 via the high voltage terminal Hv to accelerate the electron beam. The accelerated electrons collide with the fluorescent film 17 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 concept of the present invention. For example, 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 including a larger number of scanning lines (for example, the MUSE system). And other high-definition TV) systems.

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

[0094]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to specific examples. However, the present invention is not limited to these examples, and various examples within a range in which the object of the present invention is achieved. This includes the case where the element is replaced or the design is changed.

<Embodiment 1> The image forming apparatus of this embodiment is
It has a configuration similar to that of the device schematically shown in FIG. 2, and includes 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. I have. The getter is covered by a part of the Y-direction wiring.

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 FIG. However, in FIGS. 5 and 6, members having the same functions are denoted by the same reference numerals. Here, 1 is an electron source substrate, 2 is FIG.
X-directional wiring corresponding to _Doxm of _No. 3, Y-directional wiring corresponding to _Doyn of FIG. 2, 4 is a surface conduction electron-emitting device, 51
Is an interlayer insulating layer, 52 and 53 are device electrodes, 54 is a conductive film including an electron emission portion, and 55 is a device electrode 53 and a Y-direction wiring 3.
And 11 are non-evaporable getters.

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

Step-a A 0.5 nm thick silicon oxide film is formed on a cleaned blue plate glass by a sputtering method, and a 5 nm thick Cr and a 600 nm thick Au are deposited on the electron source substrate 1 by vacuum deposition. Are sequentially laminated, and a photoresist (AZ1370 Hoechst) is spin-coated with a spinner, baked, and then exposed and developed with a photomask image to form a resist pattern of the Y-directional wiring 3, and Au / Cr The deposited film was wet-etched to form a Y-directional wiring 3 having a width of 80 μm (FIG. 7A).

Step-b Next, an interlayer insulating layer 51 made of a silicon oxide film having a thickness of 1.0 μm was deposited by RF sputtering (FIG. 7).
(B)).

Step-c A photoresist pattern for forming the contact hole 55 was formed in the silicon oxide film deposited in the step b, and the interlayer insulating layer 51 was etched using the photoresist pattern as a mask to form the contact hole 55. Etching is C
RIE (Reactive I) using F ₄ and H ₂ gas
on Etching) method (FIG. 7 (c)).

Step-d After that, a pattern having a distance G between the device electrodes 52 and 53 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 52 and 53 were formed with the device electrode interval G of 3 μm and the device electrode width of 300 μm (FIG. 7D).

Step-e After forming a photoresist pattern of the X-direction wiring 2 on the device electrodes 52 and 53, Ti having a thickness of 5 nm and a thickness of 50
Au having a thickness of 0 nm was sequentially deposited by vacuum evaporation, and unnecessary portions were removed by lift-off to form an X-directional wiring 2 having a width of 300 μm (FIG. 8E).

Step-f A Cr film 56 having a thickness of 100 nm was deposited and patterned by vacuum evaporation, and a Pd amine complex solution was spin-coated thereon with a spinner, followed by heating and baking at 300 ° C. for 10 minutes.

Further, the thus formed conductive film 54 for forming an electron-emitting portion composed of Pd as a main element had a thickness of 8.7 nm and a sheet resistance of 3.2 × 10 ⁴ Ω / □. . (FIG. 8 (f)).

Step-g A desired pattern was formed by etching the Cr film 56 and the conductive film 54 for forming the electron-emitting portion after firing with an acid etchant (FIG. 8 (g)).

Step-h Except for the contact hole 55, a pattern for applying a resist was formed, and 5 nm thick Ti and 500 nm thick Au were sequentially deposited by vacuum evaporation. And
Unnecessary portions were removed by lift-off to bury the contact holes 55 (FIG. 8H).

Through the above steps, a plurality of (100 rows × 300 columns) conductive films 54 for forming the electron-emitting portion are formed on the electron source substrate 1 by simple matrix wiring using the X-directional wiring 2 and the Y-directional wiring 3. An electron source 1 was formed.

Step-i Next, a non-evaporable getter was formed on the Y-directional wiring 3 by a plasma spraying method. A method for forming a non-evaporable getter will be described with reference to FIG.

First, a mask 5 for preventing the getter from adhering to portions other than the desired portion was formed. The mask substrate 6 has 5
The mask 5 was formed by forming an opening by photolithography using an amber material (iron / nickel alloy) of a low thermal expansion material having a thickness of 00 μm. In this patterning process, the resist is applied by spraying.
A resist film 8 having a film thickness of 7 μm was formed, and this was performed by exposing the resist film 8 to an exposure solution (alkaline solution) or the like. As shown in FIG. 9A, the pattern of the mask opening has a width of 200 μm at intervals equal to the X-direction wiring intervals.
Openings having a length of 10 mm and a length of 10 mm were formed in a zigzag pattern so that the openings corresponded to a part of the wiring in the X direction.

Next, a polytetrafluoroethylene (PTF) having an average particle size of 1 μm was placed on the substrate 6 thus prepared.
E) The aqueous dispersion of the resin was spray-coated. Then, this was dried at 150 ° C. and then heat-treated at 300 ° C. for 20 minutes to form a PTFE coating 7 on the surface of the amber material.
(B)).

A resist was applied on the electron source substrate 1, and the mask 5 was covered and fixed while positioning the electron source substrate 1, and developed by UV irradiation, so that only the mask opening of the Ag wiring was exposed. (FIG. 1 (c)).

The electron source substrate 1 is mounted in a low-pressure plasma spraying apparatus, and a non-evaporable getter material (Zr (75
%)-V (20%)-Fe (5%) powder alloy). At this time, the pressure inside the pressure reducing tank was once reduced to 1.3 × 10 Pa, and then the pressure inside the tank was reduced to 4.7 × 1 Pa with Ar gas.
Thermal spraying was performed at a pressure of 0 ³ Pa. After the thermal spraying, the pressure in the tank was again reduced to 1.3 × 10 Pa, and then nitrogen gas was introduced to atmospheric pressure. After the substrate temperature was sufficiently lowered, the tank was opened to the atmosphere and taken out.

The thickness of the formed getter material 11 was about 40 μm on average (FIG. 1D).

The electron source substrate 1 is immersed in a stripping solution for the resist film 8 to be separated from the mask 5, and is subjected to a cleaning step to form a non-evaporable getter 11 on a part of the X-directional wiring. 1 was obtained (FIG. 1 (e)).

On the other hand, the mask 5 separated from the electron source substrate 1
(FIG. 1 (f)) has a getter material 10 adhered thereon.
Collection work was performed to reuse this. That is, the mask 5 was heated to 550 ° C. in an Ar gas flow to decompose the PTFE coating formed on the mask substrate 6. And
A gas was blown onto the mask base material 6 to separate the mask base material 6 from the getter material, and after cooling, only the getter material 10 was recovered. The getter material 10 thus collected was used again as a plasma spray material. Further, the mask base material 6
It was again covered with a PTFE membrane and reused.

Step-j Next, a face plate 14 serving as an image display portion was prepared. In the face plate 14, a transparent electrode (not shown) made of ITO was provided on the glass substrate 16 in order to enhance the conductivity of the fluorescent film 17. The fluorescent film 17 as an image forming member is formed of a stripe-shaped phosphor (see FIG. 3A) in order to realize a color, a black stripe is formed first, and a phosphor of each color is formed in a gap portion by a slurry method. 23R, 23G and 23B are applied to form the fluorescent film 17
Was prepared. In addition, as the material of the black stripe,
A commonly used material mainly composed of graphite was used.

A metal back 18 was provided on the inner surface side of the fluorescent film 17. After the fluorescent film 17 is formed, the metal back 18 is subjected to a smoothing treatment of the inner surface of the fluorescent film 17 (usually,
(Referred to as filming), and then Al was vacuum-deposited.

Step-k Next, the envelope 15 shown in FIG. 2 was manufactured by the following steps.

The electron source substrate 1 formed by the above-described steps
, The support frame 13, the shield 19, the ring-shaped evaporable getter 12, and the face plate 14, and the positions of the electron source substrate 1 and the phosphors of each color of the face plate 14 are strictly adjusted and sealed. An envelope 15 was formed. The sealing method is to apply frit glass to the joint,
After calcination at 0 ° C., the respective members were combined and subjected to a heat treatment at 400 ° C. for 10 minutes in Ar gas for bonding.

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

In FIG. 10, reference numeral 91 denotes an image forming apparatus (also referred to as an image display panel) in a manufacturing process, and reference numeral 92 denotes an exhaust pipe, which connects the image forming apparatus 91 and a vacuum chamber 93. The vacuum chamber 93 is connected to a gate valve 94, and the gate valve 94 is connected to an exhaust device 95. The exhaust device 95 is configured by a backup dry pump connected to a magnetic levitation type turbo molecular pump via a valve (not shown). The vacuum chamber 93 has a pressure gauge 96 for monitoring the internal pressure, and a quadrupole mass spectrometer (Q-mass) 9 for monitoring the gas partial pressure configuration inside the vacuum chamber 93.
7 is equipped.

Further, the vacuum chamber 93 is connected to an ampoule and a cylinder in which the substance to be introduced 100 is sealed through a gas introduction line 98 and a gas introduction control device 99 provided in the middle of the gas introduction line 98. In the present embodiment, a variable leak valve compatible with ultra-high vacuum is used as the gas introduction control device 99, and the introduced substance source 100 is used.
Acetone (CH ₃ ) ₂ CO was used.

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

Step-1 The gas in the envelope 15 completed in the previous step is discharged to the exhaust pipe 92.
And the exhaust device 95 exhausts the gas through the vacuum chamber 93,
After the pressure indicated by the pressure gauge 96 reached about 1 × 10 ⁻³ Pa, forming was performed using the apparatus shown in FIG.

FIG. 11 is a schematic diagram of an apparatus for applying a voltage to the image forming apparatus under the manufacturing process in the forming process. In the present embodiment, the device is used also in the subsequent activation process.

As shown in FIG. 11, in the image forming apparatus 91 in the manufacturing process, the Y-direction wirings D _{y1 to} D _yn are commonly connected and connected to the ground, while the X-direction wirings D _{x1 to} D _xm are respectively connected to the ground. Are connected to the corresponding terminals of the switching pox 104. Here, reference numeral 101 denotes a control device, and the pulse generator 10
2. The switching box 104 is controlled through a control signal bus, and the measured value measured by the ammeter 103 is obtained through a measurement data transfer bus.

The switching backs 104 selects one line from the X-direction wirings D _{x1 to} D _xm , and _supplies the selected line to the pulse generator 102 through the ammeter 103.
Is applied. The unselected lines are connected to the ground potential by the switching box 104.

The forming process was performed for each element row in the X direction for each row (300 elements). The waveform of the applied pulse was a rectangular wave pulse as shown in FIG. 12A, and the peak value (peak of the voltage difference between the element electrodes) was gradually increased from 0V. Note that the pulse width T ₁ = 1 msec and the pulse interval T ₂ = 10 msec. In addition, a rectangular wave pulse having a peak value of 0.1 V is inserted between the rectangular wave pulses (FIG. 12).
(B)) The resistance of each row was measured by measuring the current.

Then, when the resistance value exceeded 3.3 kΩ (1 MΩ per element), the forming of that row was terminated, and the processing of the next row was started. This process is performed for all rows, the forming of all the conductive films (the conductive film 54 for forming the electron emission portions) is completed, the electron emission portions are formed in each of the conductive films, and a plurality of surface conduction type electrons are formed. An electron source 1 in which emission elements were wired in a simple matrix was prepared.

Step-m Next, acetone (CH ₃ ) ₂ CO
And adjusted so that the indicated value of the pressure gauge 96 becomes about 2 × 10 ⁻³ Pa. At this time, it is confirmed that gas molecules of acetone are surely introduced into the vacuum chamber 93 by using the Q-mass 97.

Thereafter, as in the forming step, FIG.
The activation process of each electron-emitting device was performed by applying a pulse voltage through each X-direction wiring by using the apparatus 1 described above.

The pulse waveform generated by the pulse generator 102 is a rectangular wave shown in FIG.
V, pulse width T ₁ = 1 msec, pulse interval 100 m
sec. Then, by the switching box 104, repeating to switch sequentially select line for each 1msec to D _x1 to D _x100, this result, T ₁ = 1msec Each element rows, a rectangular wave of T ₂ = 100 msec is,
It is applied with a slightly shifted phase for each row (FIG. 1
3).

The ammeter 103 is used in a mode for detecting the current value in the ON state of the rectangular wave pulse (when the voltage is 15 V), and the average value of this value in each element row is 6
When the current reached 00 mA (2 mA per element), the pulse application was terminated, the inside of the envelope 15 was evacuated, and the activation process was terminated.

Step-n While the evacuation is continued, the whole of the image forming apparatus 91 and the vacuum vessel 93 is kept at 200 ° C. for 5 hours by a heating device (not shown), and is adsorbed on the envelope 15 and the inner wall of the vacuum chamber 93. (CH ₃ ) ₂ CO and its decomposed products, which are considered to be present, were once evacuated, and further maintained at 350 ° C. for 10 hours to further remove residual adsorbed gas molecules and activate the non-evaporable getter material. .

Step-o After confirming that the pressure was 1.3 × 10 ⁻⁵ Pa or less, the exhaust pipe was heated and closed with a burner. Subsequently, the evaporable getter 1 previously set outside the image display area
2 is flashed by high frequency heating.

Through the above steps, the image forming apparatus of the present embodiment was manufactured.

<Embodiment 2> In Embodiment 2, members having the same structure as those of Embodiment 1 are formed by using the same material as that of Embodiment 1 except that a polyimide resin is used as a separation film formed on a mask for plasma spraying. Was prepared and the same processing was performed to prepare the image forming apparatus of this embodiment.

The polyimide formed in this example is
A polyamic acid obtained from pyromellitic acid and oxydianiline, which is an aromatic polypyromellitamide, was formed into a water-soluble composition by an electrodeposition coating method.

Although the getter material adhered to the polyimide film on the mask by plasma spraying, the mask was separated from the electron source substrate in the same manner as in Example 1, and then heated at 500 ° C. in an Ar gas flow. As a result, the getter material could be recovered by decomposing the polyimide.

By this method, a non-evaporable getter could be formed at a desired position on the X-direction wiring.

Example 3 In Example 3, the same material as in Example 1 was used in the X direction except that a polyamideimide-based polyimide resin was used as the separation film formed on the mask for plasma spraying. A non-evaporable getter was plasma sprayed on the wiring.

In this example, polyamideimide was formed on a substrate by a spray method.

Further, dimethylformamide (DMF) was used as a resist stripping solution after plasma spraying.

When the electron source substrate was immersed in DMF,
The polyamideimide on the mask substrate was dissolved, and the getter material attached to the mask substrate was precipitated in the DMF tank. This getter material was recovered from the DMF tank, washed, and reused as a new getter material.

By this method, a non-evaporable getter could be formed at a desired position on the X-direction wiring.

<Embodiment 4> In Embodiment 4, except that an Al film was used as a separation film to be formed on a mask for plasma spraying, a material similar to that of Embodiment 1 was used to form a non-coating on the X-direction wiring. An evaporable getter was plasma sprayed.

In the present embodiment, the A
1 film was formed.

Although the getter material adhered to the Al film on the mask by plasma spraying, the mask was separated from the electron source substrate in the same manner as in Example 1, and then was placed in a 50 g / l aqueous sodium hydroxide solution. A by immersion
1 was dissolved, and the mask substrate and the getter material could be separated. After that, the getter material in the sodium hydroxide was recovered and washed, and could be reused as a new getter material.

By this method, a non-evaporable getter could be formed at a desired position on the X-direction wiring.

<Example 5> In Example 5, a non-evaporable getter was formed on a black matrix of a face plate via a metal back.

The arrangement shown in FIG. 3A was adopted as the arrangement of the phosphor and the black matrix. A method for manufacturing the image forming apparatus according to the present embodiment will be described with reference to FIG. (1) An electron source substrate was prepared using the same materials and methods as in Step-a to Step-h of Example 1.

(2) Next, the face plate 14 was formed. A fluorescent film 17, a black stripe, and a metal back 18 were formed on a glass substrate 16 using the same method as in Step-j of Example 1.

Next, the non-evaporable getter 11 was formed on the black stripe via the metal back 18. Further, a mask 5 for preventing the getter from adhering to portions other than the desired portion was formed. The mask 5 was formed by forming an opening by photolithography using a 500 μm-thick invar material (iron / nickel alloy) of a low thermal expansion material as the mask base material 6. This patterning step was performed by forming a resist film having a thickness of 7 μm by spraying a resist by spraying, exposing the resist film to an etchant (alkali solution), or the like. The pattern of the mask opening was a stripe shape as shown in FIG. 9B, and the opening corresponded to the black matrix.

Next, an aqueous dispersion of a polytetrafluoroethylene (PTFE) resin having an average particle size of 1 μm was spray-coated on the mask base material 6 thus prepared. This was dried at 150 ° C. and then heat-treated at 300 ° C. for 20 minutes to form a PTFE coating on the surface of the Invar material.

Next, a resist was applied on the face plate 14, and the mask 5 was covered and fixed while positioning on the face plate 14, and developed by UV irradiation to expose only the black matrix.

Such a face plate 14 is mounted in a low-pressure plasma spraying apparatus, and a non-evaporable getter material (Zr
(75%)-V (20%)-Fe (5%) powder alloy)
Was sprayed. At this time, the inside of the decompression tank is temporarily set to 1.3 × 10
3. Reduce the pressure in the tank to 4 Pa with Ar gas.
Thermal spraying was performed at a pressure of 7 × 10 ³ Pa. Also,
After the thermal spraying, the pressure in the tank was again reduced to 1.3 × 10 Pa, and then nitrogen gas was introduced to the atmospheric pressure. After the substrate temperature was sufficiently lowered, the tank was opened to the atmosphere and taken out. The thickness of the formed getter 11 was about 40 μ on average.

The face plate 14 is immersed in a resist stripper to separate it from the mask 5. After passing through a cleaning process, the electron source substrate 1 on which the non-evaporable getter 11 is formed on a black matrix via a metal back 18. Obtained. On the other hand, the getter material 10 adheres to the mask 5 separated from the electron source substrate 1, and a collecting operation was performed to reuse the getter material. In the recovery operation, the mask 5 was placed in an Ar gas flow 500
C. to separate the getter material 10 from the mask substrate 6 by decomposing the PTFE coating formed on the mask substrate 6.
After cooling, only the getter material 10 was recovered. The collected getter material 10 was used again as a plasma spray material. The mask substrate 6 was again covered with a PTFE film and reused.

(3) An image forming apparatus was manufactured in the same manner as in Step-k to Step-o of Example 1.

<Embodiment 6> In Embodiment 6, the matrix arrangement shown in FIG. 3B is adopted as the arrangement of the color phosphors on the face plate 14 and the shape of the black matrix. A member having a similar configuration was manufactured using the same method as in Example 4, except that the shape was such that it did not have an opening except for the position corresponding to An image forming apparatus was manufactured.

[0160] In <Comparative Example 1> Comparative Example 1, in the image forming apparatus, instead of disposing the getter by spraying, on the X-direction wirings D _x1 to D _x100, by sputtering, Zr-V-Fe
Except that a thin film of a non-evaporable getter made of an alloy was formed, a member having a similar configuration was prepared using the same material as in Example 1, and the same processing was performed to obtain an image forming apparatus of this comparative example. It was created.

Zr (75%), V (20%), Fe (5%)
%), A getter film having a shape substantially similar to that of the X-direction wiring was formed with a thickness of 300 nm.

The image forming apparatuses of Examples 1 to 6 and Comparative Example 1 were compared and evaluated.

In the comparative evaluation, simple matrix driving was performed.
The image display was caused to emit light continuously over the entire surface, and the change over time in luminance was measured.

The luminance was measured at the center of the image display area which is most susceptible to vacuum deterioration in the envelope 15. In each of Examples 1 to 6 and Comparative Example 1, the rate of change (deterioration rate) of the decrease in luminance at the beginning of driving is the highest, and the rate of deterioration gradually decreases as driving continues. However, there is a difference between the image forming apparatuses of Examples 1 to 6 and the image forming apparatus of Comparative Example 1 particularly in the value of the deterioration rate at the initial stage of driving. 6 is about 15% larger than the deterioration rate of 6.

Although the deterioration rate after long-term driving is not as large as that at the beginning of driving, a difference in luminance occurs at the beginning of driving.
Comparative Example 1 had a darker screen and lower image quality than Examples 1 to 6.

The reason why the deterioration rates of the image forming apparatuses of Examples 1 to 6 are smaller than that of Comparative Example 1 is that the non-evaporable getter formed in the image display area is formed by the sputtering method. As compared with the first getter thin film, the surface area is large and the amount (volume) of the getter material is large, so that both the initial pumping speed and the total amount of gas that can be adsorbed and exhausted are large. For this reason, in particular, it becomes possible to positively adsorb and exhaust the deteriorated gas which is often generated in the early stage of driving.
By suppressing deterioration of the electron source, a decrease in luminance is also suppressed.

<Comparative Example 2> In Comparative Example 2, members having the same structure as those of Example 1 were used, except that no heat-resistant polymer was formed on the surface of the mask for plasma spraying. Was prepared and the same processing was performed to prepare an image forming apparatus of this comparative example.

According to this method, a non-evaporable getter could be formed at a desired position on the X-direction wiring, but the getter material was fused to the mask surface and the two could not be separated. . When such a mask was further used several times, it was discarded because the shape of the opening was changed by the attached particles.

<Embodiment 7> In Embodiment 7, a horizontal field emission type electron-emitting device is used as an electron-emitting device constituting an electron source. The basic configuration of the electron source substrate is the same as that shown in the first embodiment, but the portion of the electron-emitting device has a structure schematically shown in FIG.

In FIG. 14, an emitter 133 and a gate 13 are placed on an insulating substrate 131 via an insulating layer 132.
4 are formed. The emitter 133 and the gate 1
Reference numeral 34 denotes a Pt thin film having a thickness of 0.3 μm. The tip of the emitter 133 is an electron emission portion, and the angle of the tip is 45 °.

The method of manufacturing the electron source substrate is performed in substantially the same procedure as in the first embodiment. However, instead of forming the device electrode of the surface conduction electron-emitting device performed in step-d of Example 1,
In this embodiment, an emitter electrode and a gate electrode of a horizontal field emission type electron-emitting device are formed. Further, the formation and patterning of the conductive film for forming the electron-emitting portion in the surface-conduction electron-emitting device performed in Steps-f and Step-g of Example 1 are not performed.

In forming the emitter electrode and the gate electrode, a Pt film having a thickness of 0.3 μm was formed by a sputtering method. Subsequently, after a resist is applied and baked to form a resist layer, exposure and development are performed using a photomask to form a resist pattern corresponding to the shape of the emitter 133 and the gate 134. Then, after performing dry etching to form the emitter 133 and the gate 134 having desired shapes, the resist is removed. Thereby, the emitter 133 and the gate 134 having the shape shown in FIG.
Are formed at predetermined positions on the insulating substrate 131.

Using this electron source substrate, an image forming apparatus having a getter disposed on the wiring of the electron source was formed in substantially the same procedure as in the first embodiment. However, unlike the case where the surface conduction electron-emitting device is used, the forming process and the activation process of the electron-emitting device are not required. The peak value of the voltage pulse used for driving was 100 V.

[0174]

As described above, according to the present invention, an image display region on an electron source substrate or a face plate by plasma spraying or the like has a thickness of about 10 to 100 μm and a thickness of several μm to several tens μm. A non-evaporable getter having a surface is arranged.

Therefore, the gas generated from the image display area serving as the gas emission source can be quickly and long-term exhausted by the getter having the large exhaust speed and the total exhaust amount. As a result, it is possible to suppress the deterioration of the electron-emitting device and the fluctuation of the emission current amount. 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. can do.

Further, by collecting the getter material adhering to the surface of the thermal spray mask, it is possible not only to use it again as a thermal spray material but also to use the mask repeatedly, thereby reducing the manufacturing cost.

[Brief description of the drawings]

FIG. 1 is a schematic view illustrating a first embodiment of a method for manufacturing an image forming apparatus according to the present invention.

FIG. 2 is a perspective view illustrating a structure of an envelope according to the first embodiment of the image forming apparatus of the present invention.

FIG. 3 is a schematic diagram for explaining a structure of a fluorescent film.

FIG. 4 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 electron sources in a matrix arrangement.

FIG. 5 is a schematic diagram for explaining an electron source according to the first embodiment of the present invention.

FIG. 6 is a sectional view taken along line A-A 'of the electron source shown in FIG.

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 diagram showing a pattern shape of a plasma spraying mask used in an example.

FIG. 10 is a schematic diagram illustrating an outline of a vacuum processing apparatus used for manufacturing an image forming apparatus.

FIG. 11 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. 12 is a diagram illustrating an example of a pulse voltage waveform given in a forming process.

FIG. 13 is a diagram showing a pulse voltage waveform applied to each X-direction wiring and a temporal relationship during activation processing.

FIG. 14 is a schematic view of an electron-emitting device used in Embodiment 6 of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electron source substrate 2 X direction wiring 3 Y direction wiring 4 electron emitting element 5 mask 6 mask base material 7 separation film 8 resist film 9 thermal spraying device 10 getter material 11 non-evaporable getter 12 evaporable getter 13 support frame 14 face plate 15 Enclosure 16 Glass base 17 Fluorescent film 18 Metal back 19 Shield 20 Row selection terminal 21 Signal input terminal Hv High voltage terminal 22 Black conductive material 23R, 23G, 23B Phosphor 41 Display panel 42 Scanning circuit 43 Control circuit 44 Shift register 45 Line memory 46 Synchronous signal separation circuit 47 Modulation signal generator 51 Interlayer insulating layer 52, 53 Device electrode 54 Conductive film including electron emitting portion 55 Contact hole 56 Cr film 91 Image forming apparatus in manufacturing process 92 Exhaust pipe 93 Vacuum chamber 94 Gate valve 95 Exhaust device 96 Power meter 97 Q-mass 98 gas inlet line 99 gas introduction control unit 100 introduction material source 101 controller 102 pulse generator 103 ammeter 104 switching box 131 insulating substrate 132 insulating layer 133 emitter 114 gates

Claims (15)

[Claims] A non-evaporable getter is provided in an image display area of an image forming apparatus having an electron source having a plurality of electron-emitting devices arranged on a substrate and an image forming member arranged to face the substrate. A method for forming a thermal spray mask, which is used for shielding a portion other than a getter formed by a thermal spraying method from a thermal spray source, to remove a getter material attached to the mask and facilitate reuse of the mask. Non-evaporable getter, comprising: a step of forming a getter using the mask, the step of collecting a getter material attached to the surface of the mask using a mask provided with a separation film Formation method. 2. The non-evaporable getter according to claim 1, wherein the non-evaporable getter is formed on a wiring for applying a voltage to the electron-emitting device disposed on an electron source substrate. Method of forming mold getter. 3. The non-evaporable getter according to claim 1, wherein the non-evaporable getter is formed via a metal back on a black material separating a phosphor region on the image forming member. Forming method. 4. The separation film formed on the mask surface,
The method for forming a non-evaporable getter according to claim 1, wherein the method is a heat-resistant polymer film or a metal thin film. 5. The thermal decomposition temperature of the heat-resistant polymer film is 3
The method for forming a non-evaporable getter according to claim 4, wherein the temperature is not lower than 00 ° C. 6. The method for forming a non-evaporable getter according to claim 4, wherein said metal thin film is an aluminum thin film. 7. The method for forming a non-evaporable getter according to claim 1, wherein the mask is made of an Fe-based alloy or a ceramic. 8. A method of removing and collecting the getter material attached to the mask surface, comprising a step of heating the mask to a temperature not lower than the decomposition temperature of the separation membrane and lower than the melting temperature of the mask and the getter material. The method for forming a non-evaporable getter according to any one of claims 1 to 7. 9. The method according to claim 1, wherein the method of removing and collecting the getter material attached to the mask surface includes a step of immersing the mask in a solution capable of dissolving the separation membrane. 2. The method for forming a non-evaporable getter according to claim 1. 10. The non-evaporable getter according to claim 1, wherein the getter material is Ti, Zr, or an alloy mainly containing at least one of them. Forming method. 11. The getter has a thickness of 10 to 100 μm.
m.
The method for forming a non-evaporable getter according to the above item. 12. An image, wherein a plurality of electron sources arranged in a matrix are arranged on a substrate, and a non-evaporable getter is formed by the method according to any one of claims 1 to 11. Manufacturing method of forming apparatus. 13. A method for manufacturing an image forming apparatus, comprising: an electron source having a surface conduction electron-emitting device; and forming a non-evaporable getter by the method according to claim 1. Description: Method. 14. An image forming apparatus comprising: an electron source having a horizontal field emission type electron-emitting device; and a non-evaporable getter formed by the method according to any one of claims 1 to 11. apparatus. 15. An image forming apparatus comprising a non-evaporable getter formed by the method according to claim 1. Description: