JP2000251720A - Sealing method and manufacturing device for image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize activation of a getter at a low temperature and for a short time, by setting the temperature of a part or whole of a non-evaporation getter lower than a sealing temperature when a sealing material is heated to the sealing temperature, is melted, and is sealed. SOLUTION: For performing vacuum sealing where the temperature of an in-surface non-evaporation getter 109 is controlled lower than a sealing temperature, a rear plate 103 is loaded on an assist heating hot plate 120' on an adjusting stage and a flit indirect heating hot plate 121', and an outer frame 104 is placed on the rear plate 103. A face plate 101 having exhaust pipes 111, 111' is held on an assist heating hot plate 120 and a flit indirect heating hot plate 121. A hot plate has two structures of the assist heating hot plates 120, 120' whose upper and lower parts control temperature of the in-surface non- evaporation getter 109, and the flit indirect heating hot plates 121, 121' for melting and heating flit glasses 110, 110'.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing method and a manufacturing apparatus for an image forming apparatus, and more particularly, to a flat type image display apparatus using a cold cathode electron emission source using frit glass (low melting glass). It can be suitably used for a manufacturing method and a manufacturing apparatus to be worn.

[0002]

2. Description of the Related Art Conventionally, when manufacturing an image display device in which the inside is maintained in a vacuum, a frit glass as a sealing material is applied or placed between glass members and put in a sealing furnace such as an electric furnace. Alternatively, the entire image display device is placed on a hot plate heater (in some cases, sandwiched between the hot plate heaters from above and below), and the entire image display device is heated to a sealing temperature, and the glass member at the sealed portion is fused with sealing glass. Have been.

Further, a flat-panel image display device using an electron source requires an ultra-high vacuum in order to stably operate a cold cathode electron-emitting device and the like for a long period of time, so that a substrate having a plurality of electron-emitting devices is required. And, a substrate having a phosphor at a position opposed thereto is sealed with frit glass across a frame,
A getter for adsorbing the released gas and maintaining a vacuum is provided.

There are two types of getters: a vapor deposition type and a non-evaporation type. The vapor deposition type getter heats an alloy containing Ba or the like as a main component in a vacuum glass envelope by energization or high frequency to form a vapor deposition film on the inner wall of the container. Formed (getter flash), the gas generated inside is absorbed by the activated getter metal surface, and a high vacuum is maintained. Non-evaporable getters include Ti, Zr, V, A
By arranging a getter material such as 1 or Fe and performing "getter activation" to obtain gas adsorption characteristics by heating in a vacuum, the released gas can be adsorbed.

[0005] Generally, the flat-panel image display device is thin, and the installation area and flash area of the vapor deposition type getter cannot be sufficiently secured. Therefore, it is installed near the support frame outside the image display area. Therefore, the conductance between the central portion of the image display and the getter installation region is reduced, and the effective pumping speed at the central portion of the electron-emitting device or the phosphor is reduced. In an image display device having an electron source and an image display member, a portion for generating gas is an image display area mainly irradiated with an electron beam.

Therefore, when it is desired to maintain the phosphor and the electron source in a high vacuum, it is necessary to dispose a non-evaporable getter near the phosphor and the electron source, which are the emission gas generating sources. In the case of a conventional CRT, the conductance between the phosphor and the getter film is much larger than that of a flat panel display. Therefore, the effective pumping speed is considerably larger than that of the flat panel display.

Therefore, the gas emitted from the phosphor by the electron irradiation is effectively exhausted by the getter region in the CRT, so that the gas emitted from the phosphor is quickly adsorbed and exhausted by the getter, and the pressure in the CRT is reduced. It can be kept low compared to the flat panel display. Further, since there is a getter film around the electron source, an extreme pressure increase does not occur even by the gas emitted from the electron source itself.

[0008] The generated gas deteriorates the electron source or the phosphor and is driven for a long time, so that the brightness of the image forming and displaying section is reduced. Further, a part of the generated gas is ionized to cause a discharge, which may destroy the electron source.

In view of such circumstances, US Pat.
No. 53,659 “Anode Plate for Flat Panel Display havin
g Integrated Getter ”, issured 26 Sept. 1995 to W
Allace et al. discloses that a getter member is formed in a gap between stripe-shaped phosphors on an image display member (anode plate). In this example, the getter material is electrically separated from the phosphor and the dielectric 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.

Conventionally, electron emission devices are roughly classified into two types: a thermionic emission device and a cold cathode electron emission device.
Kinds are known. The cold cathode electron emitting device includes a field emission type (hereinafter, referred to as “FE type”), a metal / insulating layer / metal type (hereinafter, referred to as “MIM type”), a surface conduction type electron emitting device, and the like. . WPD is an example of FE type
yke & WW Dolan, “Field emission”, Advance in E
lectoron Physics, 8,89 (1956) or CA Spind
t, “PHYSICAL Properties of thin-film fieldemissio
n cathodes with molybdenium cones ", J. Appl. Phy
s., 47, 5248 (1976).

As an example of the MIM type, CA Mead, “Oper
ation of Tunnel-Emission Devices ”, J. Apply. Phy
s., 32, 646 (1961).

Examples of the surface conduction electron-emitting device type include:
MI Elinson, Recio Eng. Electron Phys., 10, 1290,
(1965).

The surface conduction electron-emitting device utilizes the phenomenon that electron emission occurs when a current flows through a small-area thin film formed on a substrate in parallel with the film surface. Examples of the surface conduction electron-emitting device include a device using an SiO ₂ thin film by Elinson et al. And a device using an Au thin film [G. Dittmer: “Thin Solid Films”, 9, 317 (1972)
], In ₂ O ₃ / SnO ₂ thin film [M. Hartwel
l and CG Fonstad: “IEEE Trans. ED Conf.” 519
(1975)], and those using a carbon thin film [Hisashi Araki et al .: Vacuum, Vol. 26, No. 1, p. 22 (1983)] and the like have been reported.

A flat panel image type display device which emits a fluorescent material by an electron beam generated from these cold cathode electron-emitting devices has been developed. A surface conduction electron-emitting device emits electrons by passing a current through a conductive thin film having a high resistance part in one part. An example of such a device is disclosed in Japanese Patent Application Laid-Open No. 7-235255. It is shown.

[0015]

However, the conventional sealing method for an image display device has the following problems.

As described above, in the flat-panel image display device, the non-evaporable getter is arranged in the vicinity of the phosphor or electron source which is the source of the emitted gas. When the entire glass envelope other than the conventional sealing portion is heated to the sealing temperature and the frit glass of the sealing portion is fused, the non-evaporable getter is adversely affected at the time of sealing, and the subsequent adsorption characteristics are obtained. "Getter activation" conditions may become more severe.

That is, if the sealing temperature of the region provided with the non-evaporable getter is high, the non-evaporable getter is damaged, and the getter must be activated by high-temperature heating to obtain the adsorption characteristics. You have to do it.

At this time, for example, the aforementioned US Pat. No. 5,453,659
It is necessary to irradiate and heat the electrons emitted from the electron source by applying an appropriate potential to the getter, or to separately provide a heating means such as a means for supplying electricity only to the non-evaporable getter and a process, as shown in FIG. Further, in a getter having a low activation temperature, if the sealing temperature of the non-evaporable getter is high, the getter cannot be activated,
In some cases, adsorption characteristics can hardly be obtained.

In order to solve the above-mentioned problems of the prior art, the present invention makes it possible to reduce the damage to the non-evaporable getter at the time of sealing and to activate the getter at a low temperature or for a shorter time. An object of the present invention is to provide a method of sealing an image display device in which a vacuum baking step indispensable for a manufacturing process of a glass envelope for maintaining a vacuum inside can also serve as a getter activation step.

[0020]

In order to solve the above-mentioned problems, the present invention provides a first substrate having an electron-emitting device disposed thereon,
A second substrate on which a phosphor that receives and emits electrons emitted from the electron-emitting device is disposed, and a support that supports them is provided.A non-evaporable getter is provided inside, and a sealing material is interposed therebetween. In the sealing method of the image forming apparatus to be joined, when the image forming apparatus is held in a vacuum and the sealing material is heated and melted at a sealing temperature to be sealed, a part or all of the non-evaporable getter is provided. Is lower than the sealing temperature.

According to the present invention, there is provided a first substrate on which an electron-emitting device is arranged, a second substrate on which a phosphor which emits light by receiving electrons emitted from the electron-emitting device, and a support for supporting these. Body, comprising a non-evaporable getter inside, in an apparatus for manufacturing an image forming apparatus joined via a sealing material, means for holding the image forming apparatus in a vacuum,
Means for setting a part or the entirety of the non-evaporable getter to a temperature lower than the sealing temperature when the sealing material is heated and melted to a sealing temperature and sealed.

That is, according to the sealing method of the image forming apparatus of the present invention, the temperature of the non-evaporable getter at the time of sealing is made lower than the sealing temperature, thereby preventing the non-evaporable getter from being damaged. Further, by manufacturing the image forming apparatus in a vacuum, the deterioration of the non-evaporable getter is further suppressed.

[0023]

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

The essence of the present invention relates to a sealing method for an image forming apparatus, and is not limited to a sealing method for an image display apparatus using a surface conduction type or a field emission type electron emitting element. It goes without saying that the present invention can be applied to a sealing method of an image forming apparatus using an element.

In this embodiment, a plurality of surface conduction electron-emitting devices, which are cold cathode electron-emitting devices, are formed on the rear plate as electron-emitting devices, and a fluorescent screen (face plate) is formed.
Is provided, and a color image display device having an effective display area of 15 inches diagonally and a length to width ratio of 3: 4 is created. First, an image display device of the present invention will be described with reference to FIGS. 1 and 2, and then a method of manufacturing the image display device will be described.

FIG. 1 is a perspective view of the image display device used in the present embodiment. Parts of the panel are cut away to show the internal structure.

In FIG. 1, 1 is a face plate, 8
Denotes a rear plate, 9 denotes a support frame, and 1, 8, 9 form an airtight container for maintaining the inside of the display panel at a vacuum. When assembling the airtight container, it is necessary to seal each member so as to maintain sufficient strength and airtightness for joining.

Reference numerals 7 and 7 'denote exhaust pipes for exhausting the residual gas in the panel at the time of sealing and the exhaust gas at the time of evacuation. These are connected to a vacuum device when the inside of the airtight container is evacuated to vacuum in order to carry out the activation step and thereafter.
These exhaust pipes 7 and 7 'are also used as a gas introduction pipe 7 and an exhaust pipe 7' for an activation gas in an activation step generated during a process step.

Reference numeral 16 denotes a Ba evaporation type getter for maintaining a vacuum in the airtight container after sealing the exhaust pipe. The Ba evaporation type getter 16 forms a Ba vapor deposition film by heating to a high temperature. The Ba vapor-deposited film is a very active film and has a role as an excellent vacuum pump having the ability to adsorb and exhaust gases other than the inert gas.

On the rear plate 8, N × M surface conduction electron-emitting devices 19 are formed. (N and M are positive integers of 2 or more and are appropriately set according to the target number of display pixels.) The surface conduction electron-emitting device 19 has M column-directional wirings 12 (also referred to as lower wirings). And the N row-directional wirings 14 (also referred to as upper wirings) are used for simple matrix wiring.

Further, in FIG. 1, a non-evaporable getter 18 is arranged on the upper wiring 14 and serves as a vacuum pump for suppressing a pressure rise near the surface conduction electron-emitting device 19. .

FIG. 2 is a schematic view showing the structure of the surface conduction electron-emitting device 19. FIG. 2A is a plan view and FIG.
FIG. 2B is a cross-sectional view taken along line AA ′ of FIG. FIG.
In the figures, 11 (a) and 11 (b) are device electrodes, 15 is a conductive thin film, and 20 is an electron-emitting portion. The same members as those shown in FIG. 1 are denoted by the same reference numerals.

While the airtight container is evacuated to vacuum through the exhaust pipes 7 and 7 ', the conductive thin film 15 is subjected to forming processing through the element electrodes 11 (a) and 11 (b). As a result, the conductive thin film 15 is locally destroyed, deformed or deteriorated, and the electron-emitting portion 2 is brought into an electrically high-resistance state.
0 is formed.

Further, when the pressure in the airtight container is 1 × 10 ⁻³ P
When the pressure becomes equal to or less than a, acetone is introduced into the airtight container through the exhaust pipe 7 as an activation gas at about 1 Pa. An activation step for significantly improving the emission current is performed. Specifically, the device electrodes 11 (a), 11 of the surface conduction electron-emitting device 19
The electron emission unit 20 is activated by applying a voltage to (b) and causing a current to flow through the element. In this manner, for example, the process is performed in the same process as that disclosed in Japanese Patent Application Laid-Open No. 7-235255 described in the related art.

The face plate 1 comprises a glass substrate, a transparent conductive film ITO, a phosphor and a metal back of aluminum. In the present embodiment, I
A TO film is formed on the face plate 1. However, this need not necessarily be provided. In the present embodiment, a description will be given of a color display device.
The phosphors of the three primary colors of green and blue are separately applied. The phosphors of the three primary colors are separated by black stripes.

D _{0x1 to} D _0xm, D _{0y1 to} D _0yn, and Hv are electric connection terminals of an airtight container provided for electrically connecting the image display device to an electric circuit (not shown). D _{0x1 to} D _0xm are electrically connected to the array wiring 12 of the multi electron beam source, D _{0y1 to} D _0yn are electrically connected to the row wiring 14 of the multi electron beam source, and Hv is electrically connected to the metal back 3 of the phosphor screen.

The image display device manufactured by the manufacturing method of the present embodiment has been described above.

[0038]

[Embodiment 1] Next, a method of manufacturing an image display device according to the present embodiment will be described with reference to FIG.

(Preparation of Rear Plate 8) (R-1) The blue plate glass is washed and the silicon oxide film 17 is removed.
Is formed on the rear plate 8 formed by sputtering.
1 (a) and 11 (b) were formed by offset printing. The lower wiring 12 was formed by screen printing. Next, an interlayer insulating film 13 was formed between the lower wiring 12 and the upper wiring 14. Further, the upper wiring 14 was formed.

(R-2) Next, a conductive thin film 15 made of PdO was formed by a sputtering method and then patterned to obtain a desired form.

(R-3) Further, the getter member 18 (ribbon getter) having the non-evaporable getter formed on the nichrome ribbon was fixed on the upper wiring with an inorganic adhesive. In the present embodiment, the main components of the non-evaporable getter are Zr, V, Mn, etc., but the present invention is not limited to this.

Through the above steps, the rear plate 8 on which the surface conduction electron-emitting devices 19, the non-evaporable getters 18 and the like formed by simple matrix wiring were formed.

(R-4) Put the rear plate 8 in a vacuum device and evacuate it. When the pressure becomes 0.1 Pa or less,
A voltage was applied to the surface conduction electron-emitting device 19 through the external terminals _{Dox1 to Doxm} and _{Doy1 to Doyn} to perform a forming process on the conductive thin film 15.

(Preparation of Support Frame 9) (W-1) In order to adhere the support frame 9 and the face plate 1 to the side surface of the support frame 9 which is in contact with the face plate 1, frit glass described later is printed by a printing method. Formed.

(Facial Plate 1 Preparation) (F-1) A blue glass substrate 1 was coated with an SiO ₂ layer and ITO.
The film was formed by a sputtering method, and the phosphor 4 and the black conductor were formed by a printing method. A smoothing treatment was performed on the inner surface of the phosphor 4, and then Al was deposited using a vacuum deposition method or the like to form a metal back 3.

(F-2) In order to fix the exhaust pipes 7 and 7 'to the exhaust through holes formed on the face plate 1, frit glass was formed by a printing method.

(Adhesion of Support Frame 9, Face Plate 1, and Exhaust Pipes 7 and 7 ') (WFH-1) The support frame 9, face plate 1, and exhaust pipes 7, 7' are fixed to a fixing jig (not shown). The alignment was fixed. At this time, the frit glass was set so as to be between the support frame 9 and the face plate 1.

(WFH-2) The fixing jig was placed in an electric furnace, and the temperature was raised to 410 ° C. at a rate of 20 ° C./min.
The temperature was kept at 0 ° C. for 10 minutes, and then the temperature was lowered to room temperature at 20 ° C./min.

(WFH-2) Again, frit glass was formed by printing on the side of the support frame 9 in contact with the rear plate 1 in order to seal it with the rear plate 1.

Through the steps described above, the face plate 1 having the phosphor 4, the support frame 9, and the exhaust pipes 7 and 7 'are integrated.

(Preparation of an Airtight Container by Sealing the Integrated Body of the Rear Plate 8, the Support Frame 9, the Face Plate 1, and the Exhaust Pipes 7 and 7 ') FIG. 3 controls the non-evaporable getter 18 to a temperature lower than the sealing temperature. It is a figure explaining the vacuum sealing process performed. 21
(A) to 21 (c) are frit glass, 22 and 22 '
Is a hot plate, 23 is a laser, 24 is a laser beam, 2
5 is a vacuum device, 26 is a view port, and 27 is a mirror.

(FR-1) The rear plate 8 is placed on the hot plate 22 on an X, Y, θ adjustment stage (not shown) in the vacuum device 25, and is integrally formed (support frame / face plate / exhaust). The tubes are held by hot plates 22 and 22 'in a vacuum device 25.

At this time, the alignment of the rear plate 8 and the integrated object is performed on the X, Y, and θ adjustment stages, and the support frame 9 and the rear plate 8 are brought into contact with each other and pressurized.

(FR-2) The inside of the vacuum device 25 was evacuated by a vacuum pump, and the pressure inside the vacuum device 25 was measured with a total pressure gauge. Then, when the total pressure became 1 × 10 ⁻² Pa or less, it was heated at 20 ° C./min by the hot plates 22 and 22 ′ on the stage until the integrated body and the rear plate reached 300 ° C. Heating the members constituting the image display device at a temperature lower than the sealing temperature (400 ° C. or higher and determined by the type of the frit glass 21 (a) or the like) is referred to as assist heating. The temperature at that time is called an assist temperature. The assist heating is heating for suppressing heat distribution for preventing the glass from cracking due to thermal strain.

(FR-3) After controlling the heating of the integrated body to 300 ° C., the laser beam 24 is applied by the laser 23 to the vacuum device 2.
5 through the viewport 26 attached to the mirror 2
7 and irradiate a part of the frit glass 21 (b). Then, the laser light was locally heated to the sealing temperature by the frit glass 21 (b) and the laser light 24. The material of the view port 26 may be any material as long as it is transparent so that the laser light 24 can pass through.

The candidates for the laser 23 used in the embodiment include a semiconductor laser, a carbon dioxide laser, and a YAG laser. Any laser may be used as long as it has a wavelength that transmits glass but is absorbed by frit glass 21 (b) or the like, which is a black or gray sealing material.

The frit glass 2 is irradiated with the laser light 24.
When 1 (b) is heated and melted, the glass member is fused.
The sealing temperature of the frit glass 21 (b) is approximately 400 ° C.
As described above, as described above, the sealing temperature is determined by the type of frit glass.
Was used.

(FR-4) The laser beam 24 is applied to the vacuum device 2
The mirrors inside 5 and another mirror (not shown) were reflected to irradiate the entire circumference scan to locally heat the frit glasses 21 (a) to 21 (c). Thereafter, the temperature of the hot plates 22 and 22 'is increased to 60.degree.
℃.

[0059] (FR-5) The stage where the temperature of the integrated product reached 60 ° C
At the floor, purge gas is introduced into the vacuum device 25 from the exhaust pipe 7
Then, the inside of the vacuum device 25 is set to atmospheric pressure, and the temperature of the image display device is
Was cooled to room temperature.

(Preparation of Surface Conduction Electron-Emitting Element 19 by Vacuum Process) (S-1) The exhaust pipes 7 and 7 'are connected to a vacuum exhaust device (not shown), and the inside of the image display device is evacuated to a vacuum. .

(S-2) Subsequently, when the pressure in the image display device becomes 1 × 10 ⁻³ Pa or less, acetone as an activating gas is introduced into the airtight container through the exhaust pipe 7 at 1 Pa, and acetone is introduced. ′ While evacuating from outside the container terminals D _ox1 to
Voltage was applied to activate the process to the electron-emitting device through the D _oxm and _D oy1 ~D oyn.

(Degassing Step in Image Display Device) (D-1) After activating gas was sufficiently exhausted, the image display device was subjected to a baking degassing process. The baking temperature was 300 ° C. The heating rate was 2 ° C. per minute.

(D-2) The temperature of the image display device is 300
C. for 10 hours. This vacuum baking process not only performs the degassing process in the image display device but also activates the non-evaporable getter 18. Thereafter, the temperature was lowered to room temperature, and the Ba evaporation type getter 16 was flashed from outside the image display device by high-frequency heating to form a Ba vapor deposited film.

(D-3) Thereafter, a part of the exhaust pipes 7 and 7 'was melted and heated and sealed.

COMPARATIVE EXAMPLE 1 In order to confirm the effect of the image display device produced in Example 1, in the airtight container production step of sealing the integrated object in Example 1, the sealing was performed in the air and in the air. Heating was performed to the sealing temperature by the upper and lower hot plates 22 and 22 'without local heating by the laser beam, and the sealing process of the image display device was performed.

As described above, even if the non-evaporable getter 18 in the image display device is subjected to the sealing step at a temperature lower than the sealing temperature, cracks do not occur even after a high-temperature process such as vacuum baking. It was confirmed that the vacuum tightness was maintained without any problem.
Further, with respect to driving for a long time, a temporal change in luminance at the central portion of the image display was measured. The driving conditions of Example 1 and Comparative Example 1 were exactly the same. Surface conduction electron-emitting device 1
9 of the driving conditions, the D _{ox 1} to D _oxm, with DC + 7.5V,
_{Doy1 to Doyn} have a voltage of -7 V, a pulse width of 30 μS, and a frequency of 6
The entire screen was driven by scrolling at 0 Hz. The acceleration voltage of the face plate 11 was 6 kV. FIG. 4 shows the measurement results. The horizontal axis shows the drive time, and the vertical axis shows the luminance normalized under the initial conditions. It should be noted that there was no difference in the absolute value of the initial luminance between Example 1 and Comparative Example 1.

FIG. 4 is a diagram for comparing the luminance of the first embodiment with the luminance of the first comparative example. From FIG. 4, it was found that the image display device created in this example can be stably operated without deterioration in luminance for a long time. The reason why it is possible to operate stably is that the degree of vacuum at the center of the image display has been improved. This is because the non-evaporable getter 18 was activated in the vacuum baking step without being deteriorated in the sealing step.

In practice, the degree of vacuum improvement at the center of the image display device was confirmed by installing a total pressure gauge at the center of the face plate 1 and measuring the pressure during driving. The following study was performed to measure the pressure. In (F-2) of (Faceplate creation) of the first embodiment, a hole for passing the exhaust pipes 7 and 7 'is newly provided at the center of the phosphor 4 of the faceplate 1 of the image display device of FIG. A through hole of approximately the same size was made, and frit glass for fixing the exhaust pipes 7 and 7 'was printed.

Further, (adhesion of the support frame 9, the face plate 1, and the exhaust pipes 7 and 7 ') (WFH-1) The exhaust pipes 7 and 7' for mounting the total pressure gauge were aligned and fixed to the fixing jig. Thereafter, after the bonding step, the total pressure gauge was connected to the exhaust pipes 7 and 7 'so as to attach the total pressure gauge. The other steps and the image display device were the same as in Example 1 and Comparative Example 1 to produce an image display device.

FIG. 5 is a view showing the result of monitoring the change in the total pressure when the image display device is driven in the same manner as described above. In FIG. 5, the horizontal axis indicates the driving time, and the non-driving measurement was performed for 10 minutes as a background, and thereafter the same driving as described above was performed. The vertical axis indicates the total pressure normalized by the total pressure of the comparative example when not driven. From FIG. 5, it can be seen that the image display device manufactured according to the present embodiment has a lower pressure during non-driving and a lower pressure during driving than the conventional example. For this reason, in the present embodiment, the non-evaporable getter 18 is used.
It can be seen that the deterioration in the sealing step was suppressed and the film was effectively activated in the vacuum baking step.

[Embodiment 2] In this embodiment, a plurality of surface conduction electron-emitting devices, which are cold cathode electron-emitting devices, are formed on the rear plate as electron-emitting devices in the same manner as in Embodiment 1.
A color image display device having a fluorescent screen (face plate) and an effective display area of 15 inches diagonally and a length to width ratio of 3: 4 was prepared.

A method for manufacturing the image display device of the embodiment will be described. The same members as those described in the embodiment are denoted by the same reference numerals.

(Preparation of Rear Plate 8) (R-1) The blue plate glass is washed, and the silicon oxide film 17 is removed.
Is formed on the rear plate 8 formed by sputtering.
1 (a) and 11 (b) were formed by offset printing. The lower wiring 12 was formed by screen printing. Next, an interlayer insulating film 13 was formed between the lower wiring 12 and the upper wiring 14.
Further, the upper wiring 14 was formed.

(R-2) Next, a conductive thin film 15 made of PdO was formed by a sputtering method and then patterned to obtain a desired form.

(R-3) Further, the portions other than the upper wiring 4 were covered with a metal mask, and a non-evaporable getter 18 was laminated on the upper wiring 14 by plasma spraying to a thickness of about 50 μm. The main components of the non-evaporable getter used in this embodiment are Ti, Zr, V, F
e, etc. However, the present invention is not limited to this.

Through the steps described above, the rear plate 8 on which the surface conduction electron-emitting devices 19, the non-evaporable getters 18 and the like formed by simple matrix wiring were formed.

(R-4) Put the rear plate 8 in a vacuum device and evacuate it. When the pressure becomes 0.1 Pa or less,
A voltage was applied to the surface conduction electron-emitting device 19 through the external terminals _{Dox1 to Doxm} and _{Doy1 to Doyn} to perform a forming process on the conductive thin film 15.

(Preparation of Support Frame 9) (W-1) A frit glass 21 (a) for bonding the support frame 9 and the face plate 1 is printed on a side surface of the support frame 9 which is in contact with the face plate 1. Formed.

(Fabrication of Faceplate 1) (F-1) A blue glass substrate 1 was coated with an SiO ₂ layer and an ITO
The film was formed by a sputtering method, and the phosphor 4 and the black conductor were formed by a printing method. A smoothing treatment was performed on the inner surface of the fluorescent film, and thereafter, Al was deposited using a vacuum deposition method or the like to form a metal back 3.

(F-2) A frit glass 21 (c) for fixing the exhaust pipes 7 and 7 'in the exhaust through-hole opened on the face plate 1 was formed by a printing method.

(Adhesion of Support Frame 9, Face Plate 1, and Exhaust Pipes 7 and 7 ') (WFH-1) The support frame 9, face plate 1, and exhaust pipes 7, 7' are fixed to a fixing jig (not shown). The alignment was fixed. At this time, the frit glass 21 (a) was set so as to be between the support frame 9 and the face plate 1.

(WFH-2) The fixing jig was placed in an electric furnace, and the temperature was raised to 450 ° C. at a rate of 20 ° C./min.
The temperature was kept at 0 ° C. for 10 minutes, and then the temperature was lowered to room temperature at 20 ° C./min.

(WFH-3) To directly heat the sheet frit 21 (b), a metal foil for energizing and heating described later was arranged on the circumference in contact with the rear plate 8 except for the current introduction terminal portion. .

(WFH-4) Next, frit glass 21 (b) for sealing with the rear plate 8 was formed on the metal foil by a printing method so as to cover the metal foil.

Through the above steps, the face plate 1 having the phosphor 4, the support frame 9, and the exhaust pipes 7 and 7 ′ are integrated.

(Preparation of Airtight Container by Sealing One Piece of Rear Plate 8, Supporting Frame 9, Face Plate 1, and Exhaust Pipes 7 and 7 ') FIG. 6 shows that the non-evaporable getter 18 is controlled to a temperature lower than the sealing temperature. It is a figure explaining the vacuum sealing process performed. In FIG. 6, reference numeral 28 denotes an electric heating wire.

(FR-1) The rear plate 8 is placed on the hot plate 22 on the X, Y, θ adjustment stage (not shown) in the vacuum device 25, and is integrated (support frame / face plate / The exhaust pipe is held by hot plates 22 and 22 ′ in a vacuum device 25. At this time, the alignment of the rear plate 8 and the integrated object is performed on the X, Y, and θ adjustment stages, and the support frame 9 and the rear plate 8 are brought into contact with each other and pressed.

(FR-2) The inside of the vacuum device 25 was evacuated with a vacuum pump, and the pressure inside the vacuum device 25 was measured with a total pressure gauge. Then, when the total pressure became 1 × 10 ⁻² Pa or less, the integrated body and the rear plate were heated to 300 ° C. at 20 ° C./min on the hot plates 22 and 22 ′ on the stage. As described above, the sealing temperature (400 ° C. or higher, which is determined by the type of the frit glass 21 (a), etc.) Assist heating is heating for suppressing the heat distribution for preventing the glass from cracking due to thermal distortion. It is.

(FR-3) After the integrated material was heated to 300 ° C., an electric current was supplied from a current introduction terminal portion (not shown) of the electric heating wire 28 to bring the frit glass 21 (b) to 450 ° C.
Until local heating. In this embodiment, the frit glass 21
(B) A sealing temperature of 450 ° C. was used.

(FR-4) Frit glass 21 (b)
After melting, the temperature was gradually lowered, and held at 410 ° C. for 10 minutes to perform a distortion removing step. Thereafter, the electric power supplied to the heater for energization heating was reduced to zero. Thereafter, the temperature of the hot plates 22 and 22 'was reduced to 60 ° C at 20 ° C per minute.

(FR-5) When the temperature of the integrated material reached 60 ° C., a purge gas was introduced into the vacuum device 25 from the exhaust pipe 7, the inside of the vacuum device 25 was brought to atmospheric pressure, and the temperature was lowered to the temperature of the image display device.

(Preparation of Surface Conduction Electron-Emitting Element 19 by Vacuum Process) (S-1) The exhaust pipes 7 and 7 'were connected to a vacuum exhaust device (not shown), and the inside of the image display device was evacuated to a vacuum. .

(S-2) Subsequently, when the pressure in the image display apparatus becomes 1 × 10 ⁻³ Pa or less, acetone as an activating gas is introduced into the hermetic container through the exhaust pipe 7 at 1 Pa, and acetone is introduced. ′ While evacuating from outside the container terminals D _ox1 to
Voltage was applied to activate the process to the electron-emitting device through the D _oxm and _D oy1 ~D oyn.

(Degassing Step in Image Display Device) (D-1) After activating gas was sufficiently exhausted, the image display device was subjected to a baking degassing process. The baking temperature was 350 ° C. The heating rate was 2 ° C. per minute.

(D-2) The temperature of the image display device is 350
C. for 10 hours. This vacuum baking step serves not only for degassing in the image display device but also for activating the non-evaporable getter 8. Thereafter, the temperature was lowered to room temperature, and the Ba evaporation type getter 16 was flashed from outside the image display device by high-frequency heating to form a Ba vapor deposited film.

(D-3) Thereafter, a part of the exhaust pipes 7 and 7 'was melt-heated and sealed.

Comparative Example 2 In order to confirm the effect of the image display device produced in Example 2, each frit glass 21 (a) to 21 (c) used in Comparative Example 1 was sealed at a sealing temperature of 4
The temperature was changed to 50 ° C., and correspondingly (in the process of forming an airtight container by sealing an integral body),
And 22 ', the process was changed to a process of heating and sealing the entire image display device to a sealing temperature of 450 ° C., and the image forming device was formed in the atmosphere.

As described above, even if the non-evaporable getter 18 in the image display device is subjected to the sealing step at a temperature lower than the sealing temperature, cracks do not occur even after a high-temperature process such as vacuum baking. It was confirmed that the vacuum tightness was maintained without any problem.
Further, with respect to driving for a long time, a change with time of electron emission of the surface conduction electron-emitting device 19 at the center of the image display was measured.

The driving conditions in Example 2 and Comparative Example 2 were exactly the same. Long driving condition of the surface conduction electron-emitting device 19, D _ox1 to D _oxm at at _DC + 7.5V, D oy1 ~D
_oyn , the whole screen is driven by scrolling at a voltage of -7 V, a pulse width of 30 μS, and a frequency of 60 Hz. After 100 hours, 500 hours, 1000 hours, and 2,000 hours, all scrolling is stopped, and a 10 × 10 element in the image display central portion Only one minute was driven, and the amount of electron emission was measured.

At this time, the acceleration voltage of the face plate 1 is 8 kV. FIG. 7 shows the measurement results. The abscissa indicates the drive time, and the ordinate indicates the value obtained by standardizing the average value of the electron emission amount of the 10 × 10 elements in the central portion of the image display device by the initial value.

Note that there was no difference between the absolute values of the average electron emission amount of Example 2 and Comparative Example 2 in the initial stage. From FIG.
It has been found that the image display device manufactured in this example can be operated stably with little deterioration of the electron source for a long time. The reason why it is possible to operate stably is that the degree of vacuum at the center of the image display has been improved. This is because the non-evaporable getter 18 was activated in the vacuum baking step without being deteriorated in the sealing step. In this embodiment, it is considered that the activation of the non-evaporable getter 18 was better because the vacuum baking was performed at a high temperature.

[Embodiment 3] FIG. 8 is a diagram showing an image forming apparatus created by the embodiment. In FIG. 8, 10
3 is a rear plate, 101 is a face plate, 102
(A) is ITO, 102 (b) is a phosphor, 102 (c)
Is a metal back, 105 is a cathode, 106 is a gate electrode,
107 is an insulating layer between the gate and the cathode, 108 is a spacer,
Reference numeral 109 denotes a non-evaporable getter.

In this embodiment, a plurality of field emission devices, which are cold cathode electron emission devices, are formed on the rear plate 103 as electron emission devices, and spacers 108 are provided as atmospheric pressure support members to further reduce the weight. . The face plate 101 includes phosphor portions 102 (a) to 102 (c).
And an effective display area of 10 inches diagonally, a color image forming apparatus having an aspect ratio of 3: 4 was prepared.

First, a method for sealing an image display device according to the present invention will be described with reference to FIG. In FIG. 9, reference numeral 104 denotes a support frame, 10 denotes frit glass for bonding the face plate 101 and the support frame 104, and 110 'denotes frit glass for bonding the rear plate 103 and the support frame 104.

The gap between the face plate 101 and the rear plate 103 is 1.5 mm. Reference numeral 112 denotes a non-evaporable getter. In this embodiment, the non-evaporable getter is Z
The one composed of r, V and Fe was used,
It may be one containing Ti as a main component, and is not particularly limited to this.

Next, a method of manufacturing the image display device of the present invention will be described with reference to FIGS.

(Preparation of Rear Plate 103) (R-1) The blue plate glass is washed, and the cathode (emitter) 105 and the gate electrode 1 shown in FIG.
06, wiring, etc. were created. The cathode material was Mo.

(R-2) After the non-evaporable getter 112 and the spacer 108 were positioned on the rear plate, they were fixed with an inorganic adhesive.

Through the steps described above, the rear plate 103 on which the field emission type emission device, the non-evaporation type getter 111, the spacer 108, and the like formed by the simple matrix wiring were formed.

(Preparation of Support Frame 104) (W-1) The side of the support frame 104 which comes into contact with the face plate 101 (the upper surface of the support frame in FIG. 9), the support frame 1
A frit glass 110 for bonding the substrate 04 and the face plate 101 was formed by a printing method.

(W-2) On the side surface of the support frame 104 which comes into contact with the rear plate 103 (the lower surface of the support frame in FIG. 5),
Frit glass 110 'for bonding the support frame 104 and the rear plate 103 was formed by a screen printing method.

(Fabrication of face plate 101) (F-1) Transparent conductive film ITO 102 on blue plate glass
(A) was formed by a sputtering method, and the fluorescent film 102 (b) was formed by a printing method. A smoothing process is performed on the inner surface of the fluorescent film 102 (b), and then the fluorescent film 102 (b)
Al is deposited using a vacuum deposition method or the like, and metal back 10
2 (c) was formed.

(F-2) A non-evaporable getter 109 having a thickness of 50 μm was formed on the gate electrode 106 by plasma spraying.

(F-3) Frit glass 110 ″ for bonding an exhaust pipe to the face plate 101 was formed by screen printing.

(Face plate 101 and exhaust pipe 111)
(WFH-1) Face plate 101, exhaust pipe 11
1,111 'was aligned and fixed to a fixing jig (not shown).

(WFH-2) The fixing jig was placed in an electric furnace, and the temperature was raised to 410 ° C. at a rate of 20 ° C./min.
The temperature was kept at 0 ° C. for 10 minutes, and then the temperature was lowered to room temperature at 20 ° C./min.

(Preparation of Airtight Container by Sealing Rear Plate 103, Support Frame 104, and Face Plate 101) Referring to FIG. 9, a vacuum sealing step of controlling the non-evaporable getter 109 to a temperature lower than the sealing temperature. Will be described.

(FR-1) When the rear plate 103 is X,
Placed on hot plates 120 ′ and 121 ′ on a Y, θ adjustment stage (not shown),
The support frame 104 was placed on top. Exhaust pipes 111 and 11
The face plate 101 attached to 1 ′ is held on hot plates 120 and 121. The hot plate has two configurations, heaters 120 and 120 'for assist heating and heaters 121 and 121' for sealing heating, both above and below.

Assist heaters 120 and 120 '
Controls the temperature of the non-evaporable getter 109, and the sealing heating heaters 121 and 121 'are heaters for melting and heating the frit glasses 110 and 110'.

At this time, the positioning of the rear plate 103 and the face plate 101 was performed on the X, Y, and θ adjustment stages, and the face plate 101, the support frame 104, and the rear plate 103 were brought into contact with each other and pressed.

(FR-2) 280 as assist heating
Assist heaters 120 and 12 on stage up to ° C
Heated at 20 ° C per minute at 0 '. At the same time, the sealing heaters 121 and 121 'were also synchronized and the temperature was raised to 280C.

(FR-3) After the integrated material was heated to 350 ° C., the frit glasses 110 and 110 ′ were heated to 450 ° C. by the sealing heaters 121 and 121 ′. In this embodiment, frit glass 110 to 110 'is used.
The sealing temperature of 450 ° C. was used.

(FR-4) Frit glass 110, 1
After 10 ′ was melted, the temperature was gradually lowered, and held at 410 ° C. for 10 minutes to perform a distortion removing step. Thereafter, the heaters 121 and 121 ′ for sealing heating are turned into heaters 120 for assist heating.
After cooling down to the same temperature as in Steps 1 and 120 ', the temperature of all hot plates was lowered to room temperature at 20 ° C./min.

(Vacuum Process) (S-1) First, the exhaust pipe 1 used for gas flow sealing
A portion of 11 'was melted by heating and sealed. The exhaust pipe 111 was connected to a vacuum exhaust device (not shown), and the inside of the image display device was evacuated to a vacuum.

(Degassing Step in Image Display Device) (D-1) When the pressure in the airtight container becomes 1 × 10 ⁻⁴ Pa or less, the non-evaporable getter 112 is heated by an external high-frequency heating device. The degassing and activation of the non-evaporable getter 112 were performed. The activation temperature of the non-evaporable getter 112 is determined by the non-evaporable getter to be used. In this embodiment, the heating treatment is performed at 500 ° C. for 5 minutes.

(D-2) Next, a baking degassing process is performed on the airtight container. The baking temperature was 350 ° C. The heating rate was 2 ° C. per minute.

(D-3) When the temperature of the airtight container is maintained at 350 ° C. for 10 hours, the exhaust pipes 110 and 110 ′
Was heated and melted, and sealing was performed.

(D-4) After the sealing was completed, the temperature of the airtight container was lowered at a rate of 20 ° C./min and cooled to room temperature.

Comparative Example 3 In order to confirm the effect of the image display device produced in Example 3, the same configuration and process as in Example 3 were performed (sealing of the rear plate 103, the support frame 104, and the face plate 101). The process of heating and sealing the entire image display device to a sealing temperature of 450 ° C. was changed by using an assist heater and a sealing heater to form an image forming apparatus.

As described above, even if the non-evaporable getter 112 in the image display device is subjected to the sealing step at a temperature lower than the sealing temperature, cracks and the like do not occur through a high-temperature process such as vacuum baking. It was confirmed that there was no air-tightness, and the number of discharges during 100 hours of initial driving of the field emission device was measured. The driving conditions were the same for Example 3 and Comparative Example 3. The gate voltage was set to +120 V, and the acceleration voltage for metal back was set to 300 V.

[0131] Table 1 shows the number of discharges of the field emission devices of Example 3 and Comparative Example 3. From Table 1, it was found that the image display device manufactured in this example can be stably operated with little discharge. The reason for the stable operation is that the non-evaporable getter can be activated in the vacuum baking process without deteriorating in the sealing process, and the number of discharges has been reduced because the gas released during driving was removed. Seem.

[0132]

According to the present invention, when the image forming apparatus is held in a vacuum and the sealing material is heated and melted to the sealing temperature and sealed, a part of the non-evaporable getter is formed. All are sealed at a temperature lower than the sealing temperature. Therefore, damage at the time of sealing the non-evaporable getter can be suppressed. This makes it easier to perform getter activation for obtaining later adsorption characteristics, and can perform getter activation in a normal vacuum baking step.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a sealing method of an image display device according to an embodiment.

FIG. 2 is a perspective view of the image display device used in the present embodiment.

FIG. 3 is a schematic diagram illustrating a configuration of a surface conduction electron-emitting device.

FIG. 4 is a diagram showing a change over time in luminance of Example 1 and Comparative Example 1.

FIG. 5 is a diagram showing pressures of the image display devices of Example 1 and Comparative Example 1.

FIG. 6 is a diagram illustrating a sealing method of the image display device according to the present embodiment.

FIG. 7 is a graph showing the change over time in the average electron emission amount in Example 2 and Comparative Example 2.

FIG. 8 is a schematic diagram showing a configuration of a field emission type electron emission element.

FIG. 9 is a diagram illustrating a sealing method of the image display device according to the present embodiment.

[Explanation of symbols]

1, 101 Face plate 7, 7 ', 111, 111' Exhaust pipe 8, 103 Rear plate 9, 104 Outer frame 21 (a), 21 (b), 110, 110 ', 110 "
Frit glass 16 Evaporation type getter 112 Ring type non-evaporation type getter 19 Surface conduction type emission element 12 Column direction wiring (lower wiring) 13 Insulating layer between lower wiring and upper wiring 14 Row wiring (upper wiring) 102 (a) Transparent Conductive film ITO 102 (b) Fluorescent film 102 (c) Metal back 11 (a), 11 (b) Device electrode 15 Conductive thin film 20 Electron emission section 105 Cathode 106 Gate electrode 107 Gate / cathode insulating layer 108 Spacer 18, 109 In-plane non-evaporable getter 112 Ring non-evaporable getter 22, 22 ', 120, 120' Assist heating hot plate 23 Laser light source 24 Laser beam 25 Sealing vacuum device 26 Viewport 27 Mirror 28 Frit Local heating metal Foil heater 121, 121 'Hot plate for indirect heating of frit

Claims (7)

[Claims] A first substrate on which an electron-emitting device is arranged;
A second substrate on which a phosphor that receives and emits electrons emitted from the electron-emitting device is disposed, and a support that supports them is provided.A non-evaporable getter is provided inside, and a sealing material is interposed therebetween. In the sealing method of the image forming apparatus to be joined, when the image forming apparatus is held in a vacuum and the sealing material is heated and melted to a sealing temperature and sealed, a part or all of the non-evaporable getter is provided. At a temperature lower than the sealing temperature. 2. The method according to claim 1, wherein the sealing material is a glass frit. 3. The method according to claim 1, wherein the sealing material is heated by optical means. 4. The sealing method for an image forming apparatus according to claim 1, wherein the sealing material is heated by applying a current to a metal foil or a metal film disposed adjacent to the sealing material. 5. The image according to claim 1, wherein the sealing material is indirectly heated via the support or any or all of the first substrate and the second substrate. A method of sealing a forming apparatus. 6. The method according to claim 1, wherein the electron-emitting device is a surface conduction electron-emitting device or a field emission electron-emitting device. 7. A first substrate having an electron-emitting device disposed thereon,
A second substrate on which a phosphor that receives and emits electrons emitted from the electron-emitting device is disposed, and a support that supports them is provided.A non-evaporable getter is provided inside, and a sealing material is interposed therebetween. In a manufacturing apparatus of an image forming apparatus to be joined, a unit for holding the image forming apparatus in a vacuum, and when heating and melting the sealing material to a sealing temperature and sealing, a part of the non-evaporable getter or Means for lowering the temperature of the entirety to below the sealing temperature.