JP2002184313A - Manufacturing method of image display device and sealant filling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of an image display device that can steadily and easily perform sealing in vacuum atmosphere, and a sealant filling device. SOLUTION: The vacuum outer case of the image display device has a back substrate and a front substrate 11 which are arranged opposed to each other and of which periphery parts are sealed via the side wall. When the front substrate and side wall are sealed together, a primary coat 31 and on top of it an indium layer 32 are formed on these sealing faces. The indium layer is continuously formed by filling the molten indium on the primary coat, while applying ultrasonic waves on it. By heating and melting indium in the vacuum atmosphere, the front substrate and back substrate are mutually sealed via the side wall.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an image display device having substrates opposed to each other and a plurality of pixel display elements provided between the substrates, and a sealing material filling device.

[0002]

2. Description of the Related Art In recent years, electron-emitting devices (hereinafter referred to as emitters) have been developed as next-generation light-weight and thin flat-panel display devices.
Are being developed, and a display device in which the display device is arranged to face the phosphor screen is being developed. As the emitter, a field emission type or surface conduction type element is assumed. Generally, a display device using a field emission type electron-emitting device as an emitter is a field emission display (hereinafter, referred to as an FED), and a display device using a surface conduction type electron-emitting device as an emitter is a surface emission type. This is called a display (hereinafter, referred to as SED).

For example, an FED generally has a front substrate and a rear substrate opposed to each other with a predetermined gap therebetween.
These substrates constitute a vacuum envelope by joining their peripheral parts to each other via a rectangular frame-shaped side wall.
A phosphor screen is formed on the inner surface of the front substrate, and a number of emitters are provided on the inner surface of the rear substrate as electron emission sources for exciting the phosphor to emit light. In addition, a plurality of support members are disposed between the rear substrate and the front substrate to support the atmospheric load applied thereto.

The potential on the rear substrate side is almost 0 V, and an anode voltage Va is applied to the phosphor screen. An image is displayed by irradiating the red, green, and blue phosphors constituting the phosphor screen with an electron beam emitted from the emitter to cause the phosphors to emit light.

In such an FED, the gap between the front substrate and the rear substrate can be set to several mm or less, and compared with a cathode ray tube (CRT) currently used as a display of a television or a computer. Lightening and thinning can be achieved.

[0006]

SUMMARY OF THE INVENTION The above-mentioned flat panel display device
Then, the degree of vacuum inside the vacuum envelope is set to, for example, 10^-5-10
^-6It is necessary to keep Pa. In the conventional evacuation process, vacuum
Baking process to heat the envelope to about 300 ° C
Release the surface adsorbed gas inside the envelope,
Although the inside of the envelope was exhausted through the exhaust pipe,
In such an exhaust method, the surface adsorbed gas is sufficiently released.
I can't do that.

For example, Japanese Patent Application Laid-Open No. Hei 9-82245 discloses a configuration in which a metal back formed on a phosphor screen of a front substrate is covered with a getter material made of Ti, Zr, or an alloy thereof. A flat panel display device having a configuration in which the device itself is formed with the above-described getter material, or a configuration in which the getter material as described above is arranged in a portion other than the electron-emitting device in the image display area is described.

However, in the image display device disclosed in Japanese Patent Application Laid-Open No. 9-82245, since the getter material is formed by a normal panel process, the surface of the getter material is naturally oxidized. Since the getter material is particularly important in the degree of surface activity, a getter material whose surface has been oxidized cannot obtain a satisfactory gas adsorption effect.

As a method of increasing the degree of vacuum inside the vacuum envelope, the back substrate, the side walls, and the front substrate are put into a vacuum apparatus, and they are subjected to baking and electron beam irradiation in a vacuum atmosphere to adsorb the surface. After the gas is released, a method of forming a getter film and sealing the side wall to the rear substrate and the front substrate using frit glass or the like in a vacuum atmosphere is considered. According to this method, the surface adsorption gas can be sufficiently released by the electron beam cleaning, and the getter film is not oxidized, and a sufficient gas adsorption effect can be obtained. Further, since no exhaust pipe is required, the space of the image display device is not wasted.

However, when sealing is performed using frit glass in a vacuum, it is necessary to heat the frit glass to a high temperature of 400 ° C. or more. At that time, a number of bubbles are generated from the frit glass, and There is a problem that the hermeticity and sealing strength of the enclosure are deteriorated, and the reliability is reduced. In addition, due to the characteristics of the electron-emitting device, it may be better to avoid raising the temperature to 400 ° C. or higher. In such a case, a method of sealing with frit glass is not preferable.

The present invention has been made in view of the above points, and has as its object to provide a method of manufacturing an image display device capable of easily and reliably performing sealing in a vacuum atmosphere, and a sealing material filling device. Is to provide.

[0012]

In order to achieve the above object, a method for manufacturing an image display device according to the present invention comprises: an envelope having a rear substrate, and a front substrate opposed to the rear substrate; A plurality of pixel display elements provided inside the envelope, and in a method of manufacturing an image display device including: a sealing surface between the rear substrate and the front substrate, while applying ultrasonic waves A step of filling the molten metal sealing material, and after filling the metal sealing material, heat and melt the metal sealing material in a vacuum atmosphere, and connect the back substrate and the front substrate to the sealing surface. And a step of directly or indirectly sealing.

According to another aspect of the present invention, there is provided a method of manufacturing an image display device, comprising: a back substrate, a front substrate opposed to the back substrate, a peripheral portion of the front substrate, and a peripheral portion of the rear substrate. An envelope having a side wall disposed between the front substrate and the rear substrate, and a plurality of pixel display elements provided inside the envelope, wherein the front substrate and the side wall are provided. Wherein at least one of the sealing surface between the back substrate and the side wall is sealed with a metal sealing material layer. On the surface, a step of filling the molten metal sealing material while applying ultrasonic waves, and after filling the metal sealing material, heat and melt the metal sealing material in a vacuum atmosphere, the back substrate, A step of sealing the front substrate and the side walls with the sealing surface; It is characterized by comprising a.

Further, according to the method of manufacturing an image display device according to the present invention, the step of filling the metal sealing material includes applying the molten metal sealing material along the sealing surface while applying ultrasonic waves. The method is characterized by including a step of continuously filling and forming a metal sealing material layer extending along the sealing surface.

Further, according to the method of manufacturing an image display device of the present invention, the method further comprises the step of forming an underlayer different from the metal sealing material on the sealing surface. It is characterized in that the above-mentioned metal sealing material is filled on this underlayer.

In the method for manufacturing an image display device according to the present invention, a low-melting metal material having a melting point of 350 ° C. or less is used as the metal sealing material, for example, indium or an alloy containing indium. The underlayer is preferably a material having good wettability and airtightness with respect to the metal sealing material, that is, a material having high affinity, and at least one of silver, gold, aluminum, nickel, cobalt, and copper is preferable. A metal paste containing at least one of silver, gold, aluminum, nickel, cobalt, and copper, a metal plating layer or a deposition film, or a glass material is used.

According to the method of manufacturing the image display device having the above-described structure, the front substrate and the rear substrate are directly or indirectly sealed using the metal sealing material layer, thereby being provided on the rear substrate. The sealing can be performed at a low temperature that does not thermally damage the electron-emitting device or the like. Further, unlike the case where frit glass is used, many air bubbles are not generated, and the airtightness and sealing strength of the vacuum envelope can be improved. Furthermore, when filling the metal sealing material with respect to the sealing surface, the metal sealing material is filled while applying ultrasonic waves, whereby the wettability of the metal sealing material with respect to the sealing surface is improved, Even when indium or the like is used as the adhesive, it is possible to satisfactorily fill the desired position with the metal sealing material. Therefore, it is possible to obtain a method of manufacturing an image display device that can easily and reliably perform sealing in a vacuum atmosphere.

In addition, when the molten metal sealing material is continuously filled along the sealing surface, the molten metal sealing material is filled while applying ultrasonic waves, so that the molten metal sealing material is filled along the sealing surface. It is possible to form a metal sealing material layer that extends continuously.

After forming an underlayer different from the above-mentioned metal sealing material on the sealing surface, the above-mentioned metal sealing material is filled on this underlayer, so that the filled metal sealing material is used at the time of sealing. Is heated and melted, the underlying layer prevents the metal sealing material from flowing and can be held at a predetermined position. Therefore,
Handling is easy, and sealing can be easily and reliably performed in a vacuum atmosphere. In particular, by filling the metal sealing material while applying ultrasonic waves, at the time of filling,
Since a part of the metal sealing material is diffused into the underlayer to form an alloy layer, the flow of the metal sealing material can be more reliably prevented and held at a predetermined position during sealing.

In the step of filling the metal sealing material, the discharge amount of the metal sealing material is controlled by one of the ultrasonic oscillation output and the discharge hole diameter of the metal sealing material. Can be.

On the other hand, the sealing material filling apparatus according to the present invention
What is claimed is: 1. A sealing material filling apparatus for filling a sealing surface with a metal sealing material in the manufacture of an image display device, comprising: a support for positioning and supporting an object to be sealed having the sealing surface; A storage portion for storing the material, a nozzle for filling the sealing surface with the molten metal sealing material sent from the storage portion, and ultrasonic waves to the molten metal sealing material filled from the nozzle to the sealing surface. It is characterized by comprising a filling head having an ultrasonic generator for applying the electric power, and a head moving mechanism for moving the filling head relatively to the sealing surface.

[0022]

Embodiments of the present invention will be described below in detail with reference to the drawings. First, an FED will be described as an example of an image display device manufactured by the manufacturing method according to the present embodiment.

As shown in FIGS. 1 and 2, this FED
Has a front substrate 11 and a rear substrate 12 each made of rectangular glass as an insulating substrate, and these substrates are opposed to each other with a gap of about 1.5 to 3.0 mm. The front substrate 11 and the rear substrate 12 have a flat rectangular vacuum envelope 10 whose peripheral edges are sealed via a rectangular frame-shaped side wall 18 made of glass and whose inside is maintained in a vacuum state. Make up.

Inside the vacuum envelope 10, a back substrate 12
And to support the atmospheric pressure load applied to the front substrate 11,
A plurality of support members 14 are provided. These support members 14 extend in a direction parallel to the long sides of the vacuum envelope 10 and are arranged at predetermined intervals along a direction parallel to the short sides. The shape of the support member 14 is not particularly limited to this, and a columnar support member may be used.

As shown in FIG. 3, a phosphor screen 16 is formed on the inner surface of the front substrate 11. The phosphor screen 16 is formed of phosphor layers R, G, and B emitting three colors of red, green, and blue, and a matrix-shaped black light absorbing portion 20. The above-described support member 14 is placed so as to be hidden by the shadow of the black light absorbing portion. On the phosphor screen 16, an aluminum layer (not shown) is deposited as a metal back.

As shown in FIG. 2, on the inner surface of the rear substrate 12, a large number of field emission type electron-emitting devices each emitting an electron beam are provided as electron emission sources for exciting the phosphor layers R, G, and B. 22 are provided. These electron-emitting devices 22 are arranged in a plurality of columns and a plurality of rows corresponding to each pixel, and function as a pixel display device.

More specifically, a conductive cathode layer 24 is formed on the inner surface of the back substrate 12, and a silicon dioxide film 26 having a number of cavities 25 is formed on the conductive cathode layer. . On the silicon dioxide film 26, a gate electrode 28 made of molybdenum, niobium or the like is formed. A cone-shaped electron-emitting device 22 made of molybdenum or the like is provided in each cavity 25 on the inner surface of the back substrate 12. In addition, on the back substrate 12, a matrix-like wiring (not shown) connected to the electron-emitting device 22 is formed.

In the FED configured as described above,
The video signal is input to the electron-emitting device 22 and the gate electrode 28 formed in a simple matrix system. On the basis of the electron-emitting device 22, when the brightness is the highest, +
A gate voltage of 100 V is applied. Further, +10 kV is applied to the phosphor screen 16. The size of the electron beam emitted from the electron-emitting device 22 is modulated by the voltage of the gate electrode 28, and the electron beam excites the phosphor layer of the phosphor screen 16 to emit light, thereby displaying an image. .

As described above, since a high voltage is applied to the phosphor screen 16, a high strain point glass is used for the front substrate 11, the rear substrate 12, the side wall 18, and the plate glass for the support member 14. . Further, as described later, the space between the rear substrate 12 and the side wall 18 is sealed by a low melting point glass 30 such as frit glass, and the front substrate 11 and the side wall 1 are sealed.
8 is sealed by a sealing layer 33 in which an underlayer 31 formed on the sealing surface and an indium layer 32 formed on the underlayer are fused.

Next, a method of manufacturing the FED configured as described above will be described in detail. First, the phosphor screen 16 is formed on a plate glass to be the front substrate 11. For this, a glass sheet having the same size as the front substrate 11 is prepared, and a stripe pattern of the phosphor layer is formed on the glass sheet by a plotter machine. Exposure is achieved by placing the plate glass on which the phosphor stripe pattern is formed and the plate glass for the front substrate on a positioning jig and setting it on an exposure table.
Develop to produce phosphor screen 16.

Subsequently, the electron-emitting devices 22 are formed on the glass plate for the rear substrate. In this case, a matrix-shaped conductive cathode layer is formed on a sheet glass, and an insulating film of a silicon dioxide film is formed on the conductive cathode layer by, for example, a thermal oxidation method, a CVD method, or a sputtering method.

Thereafter, a metal film for forming a gate electrode such as molybdenum or niobium is formed on the insulating film by, for example, a sputtering method or an electron beam evaporation method. Next, a resist pattern having a shape corresponding to the gate electrode to be formed is formed on the metal film by lithography. Using the resist pattern as a mask, the metal film is etched by a wet etching method or a dry etching method to form a gate electrode 28.

Next, the insulating film is etched by wet etching or dry etching using the resist pattern and the gate electrode as a mask to form a cavity 25. Then, after removing the resist pattern, a release layer made of, for example, aluminum or nickel is formed on the gate electrode 28 by performing electron beam evaporation from a direction inclined at a predetermined angle with respect to the rear substrate surface. Thereafter, for example, molybdenum as a material for forming a cathode is deposited by an electron beam evaporation method from a direction perpendicular to the surface of the rear substrate. Thereby, each cavity 25
Is formed inside the device. Subsequently, the release layer is removed by a lift-off method together with the metal film formed thereon.

Subsequently, the space between the peripheral portion of the rear substrate 12 on which the electron-emitting devices 22 are formed and the rectangular frame-shaped side wall 18 are sealed to each other with low-melting glass 30 in the atmosphere. At the same time, the plurality of support members 14 are sealed on the rear substrate 12 with the low-melting glass 30 in the atmosphere.

Thereafter, the rear substrate 12 and the front substrate 11 are sealed to each other via the side wall 18. In this case, as shown in FIG. 4, first, a base layer 31 is formed to have a predetermined width over the entire circumference on the upper surface of the side wall 18 serving as the sealing surface and on the inner peripheral edge of the front substrate 11. In the present embodiment, the base layer 31 is formed by applying a silver paste.

Subsequently, indium as a metal sealing material is applied on each underlayer 31 to form an indium layer 32 extending continuously over the entire circumference of each underlayer. The width of the indium layer 32 is formed to be smaller than the width of the underlayer 31, and the indium layer is applied in such a manner that both side edges of the indium layer are separated from the both side edges of the underlayer 31 by predetermined gaps. For example, if the width of the side wall 18 is 9 mm, the width of the underlayer 31 is 8 mm, and the width of the indium layer 32 is about 6 mm.

The metal sealing material has a melting point of about 3
It is desirable to use a low melting point metal material excellent in adhesion and bonding at 50 ° C. or lower. Indium (In) used in the present embodiment has a melting point as low as 156.7 ° C.,
It has excellent features such as low vapor pressure, soft and strong impact resistance, and does not become brittle even at low temperatures. In addition, it can be directly bonded to glass depending on conditions, and is a material suitable for the purpose of the present invention.

Further, as the low melting point metal material, an alloy to which elements such as silver oxide, silver, gold, copper, aluminum, zinc, tin and the like are added alone or in combination can be used instead of In alone. For example, in the eutectic alloy of In97% -Ag3%, the melting point is further reduced to 141 ° C., and the mechanical strength can be increased.

In the above description, the expression "melting point" is used, but in the case of an alloy composed of two or more kinds of metals, the melting point may not be determined singly. Generally, in such a case, the liquidus temperature and the solidus temperature are defined. The former is the temperature at which part of the alloy starts to solidify when the temperature is lowered from the liquid state, and the latter is the temperature at which all of the alloy solidifies. In the present embodiment, for convenience of explanation,
In such a case, the expression "melting point" will be used, and the solidus temperature will be called the melting point.

On the other hand, for the underlayer 31 described above, a material having good wettability and airtightness with respect to the metal sealing material, that is, a material having high affinity for the metal sealing material is used. In addition to the silver paste described above, a metal paste such as gold, aluminum, nickel, cobalt, and copper can be used. In addition to the metal paste, as the base layer 31, a metal plating layer of silver, gold, aluminum, nickel, cobalt, copper, or the like, a deposited film, or a glass material layer can be used.

Here, the filling of the indium onto the underlayer 31 formed on the sealing surface, that is, the application of the indium, is performed using the following sealing material filling apparatus. As shown in FIG. 5, the sealing material filling apparatus includes a support table 40 having a flat mounting surface 40a, and a flat rectangular plate-shaped hot plate 42 and a hot plate on the hot plate. A positioning mechanism 44 for positioning an object to be sealed, a filling head 46 for filling a sealing material on the object to be sealed, and a head moving mechanism 48 for moving the filling head relative to the object to be sealed. I have.

On the hot plate 42, the back substrate 12 or the front substrate 11 on which the side wall 18 is sealed is placed as an object to be sealed. The hot plate 42 also functions as a heating unit for heating the mounted object.

The positioning mechanism 44 includes, for example, three fixed positioning claws 50 abutting on two orthogonal sides of the front substrate 11 placed on the hot plate 42, and two other positioning claws 50 on the front substrate 11, respectively. Abutment, positioning claw 50
And two pressing claws 52 for elastically pressing the front substrate 11 toward the front side.

As shown in FIGS. 5 and 6, the filling head 46 is provided with a storage portion 54 for storing the molten indium, and a nozzle 55 for filling the sealing surface of the front substrate 11 with the molten indium sent from the storage portion. And an ultrasonic transducer 56 fixed to the outer surface of the nozzle 55 and functioning as an ultrasonic generator. Further, a supply pipe 58 for supplying a purge gas is connected to the filling head 46, and a heater unit 60 for heating the nozzle 55 is provided.

As shown in FIG. 5, the head moving mechanism 48 moves the filling head 46 perpendicular to the mounting surface 40a of the support table 40, that is, with respect to the front substrate 11 mounted on the hot plate 42. And a Z-axis driving robot 62 movably supported in a vertical Z-axis direction, and a Z-axis driving robot 62 supported in a reciprocating manner in a Y-axis direction parallel to the short side of the front substrate 11. Y-axis driving robot 6
4 is provided. Further, the Y-axis driving robot 64 is supported by the X-axis driving robot 66 and the auxiliary rail 67 fixed on the mounting surface 40a so as to be reciprocally driven along the X-axis direction parallel to the long side of the front substrate 11. Have been.

When applying indium using the above-described sealing material filling apparatus, as shown in FIG. 5, the front substrate 11 is placed on the hot plate 42 with the sealing surface facing upward, and the positioning mechanism 44 is used. To a predetermined position. Subsequently, as shown in FIG. 6, after setting the filling head 46 in which the molten indium is stored to a desired filling start position, the sealing surface of the front substrate 11, here, Underlayer 3 formed on front substrate 11
The filling head 46 is moved at a predetermined speed along (1). Then, while moving the filling head 46, the molten indium is continuously filled from the nozzle 55 onto the base layer 32, and the indium layer 32 continuously extending along the base layer is formed over the entire circumference. At this time, the ultrasonic transducer 56 is operated at the same time, and the molten indium is filled onto the base layer 31 while applying ultrasonic waves to the molten indium.

Here, the ultrasonic waves are applied in a direction perpendicular to the sealing surface of the front substrate 11, that is, the surface of the underlying layer, and the frequency of the ultrasonic waves is set to, for example, 30 to 40 kHz.

As described above, by filling indium while applying ultrasonic waves, the sealing surface or the underlying layer 31 is filled.
The wettability of indium with respect to the indium is improved, and it becomes possible to satisfactorily fill the desired position with indium. Further, the molten indium can be continuously filled along the underlayer 31, so that an indium layer extending continuously along the underlayer can be formed. Furthermore, by filling the molten indium while applying ultrasonic waves,
At the time of filling, a part of indium diffuses into the surface portion of the underlayer 31 to form an alloy layer.

In the step of filling indium, either the oscillation output of the ultrasonic wave or the diameter of the indium discharge hole of the nozzle 55 is adjusted to control the amount of indium discharged, thereby forming the indium formed. The thickness, width and the like of the layer can be adjusted.

On the other hand, the side wall 18 sealed to the back substrate 12
In the case where indium is filled on the sealing surface, here, the underlayer 31, the back substrate 12 is positioned on the hot panel 42 of the sealing material filling device and the filling head 4 is filled in the same manner as described above.
According to 6, the molten indium is continuously filled along the underlayer 31 while applying the ultrasonic wave, and the indium layer 32 continuously extended along the underlayer 31 is formed.

Next, a front substrate 11 having an underlayer 31 and an indium layer 32 formed on a sealing surface, and a side wall 18 sealed to a back substrate 12 and an underlayer 31 and an indium layer 32 As shown in FIG. 7, the back side assembly formed with is held by a jig or the like (not shown) in a state where the sealing surfaces face each other and at a predetermined distance so as to face each other. It is put into the processing equipment.

As shown in FIG. 8, this vacuum processing apparatus 10
Numeral 0 has a load chamber 101, a baking, electron beam cleaning chamber 102, a cooling chamber 103, a getter film deposition chamber 104, an assembling chamber 105, a cooling chamber 106, and an unloading chamber 107 provided in order. . Each of these chambers is configured as a processing chamber capable of performing vacuum processing, and all the chambers are evacuated during the manufacture of the FED. Adjacent processing chambers are connected by a gate valve or the like.

The rear-side assembly and the front substrate 11 facing each other at a predetermined interval are put into a load chamber 101, and after the inside of the load chamber 101 is evacuated to a vacuum atmosphere, they are sent to a baking and electron beam cleaning chamber 102. . In the baking and electron beam cleaning chamber 102, when the high vacuum degree of about 10 ⁻⁵ Pa is reached, the back-side assembly and the front substrate 11 are removed by 300 mm.
Baking is performed by heating to a temperature of about ° C. to sufficiently release the surface adsorption gas of each member.

At this temperature, the indium layer (having a melting point of about 156)
C) 32 melts. However, since the indium layer 32 is formed on the base layer 31 having a high affinity, the indium is held on the base layer 31 without flowing, and the indium layer 32 is provided on the electron emission element 22 side, the outside of the back substrate, or the phosphor screen. Outflow to the 16 side is prevented.

In the baking / electron beam cleaning chamber 102, simultaneously with heating, an electron beam generator (not shown) attached to the baking / electron beam cleaning chamber 102 sends a phosphor screen surface of the front substrate 11 and a back surface. An electron beam is irradiated on the electron-emitting device surface of the substrate 12. Since the electron beam is deflected and scanned by a deflecting device mounted outside the electron beam generator, it is possible to clean the entire surface of the phosphor screen surface and the electron emission element surface with the electron beam.

After the heating and the electron beam cleaning, the rear substrate side assembly and the front substrate 11 are sent to the cooling chamber 103, for example, about 1 mm.
Cool to a temperature of 00 ° C. Subsequently, the back-side assembly and the front substrate 11 are sent to a getter film deposition chamber 104, where a Ba film is deposited as a getter film outside the phosphor screen. The surface of the Ba film is prevented from being contaminated with oxygen, carbon, or the like, and can maintain an active state.

Next, the rear-side assembly and the front substrate 11 are sent to an assembly chamber 105, where they are heated to 200 ° C., and the indium layer 32 is again melted or softened into a liquid state.
In this state, the front substrate 11 and the side wall 18 are joined and pressurized at a predetermined pressure, and then the indium is cooled and solidified. Thus, the front substrate 11 and the side wall 18 are sealed by the sealing layer 33 in which the indium layer 32 and the base layer 31 are fused, and the vacuum envelope 10 is formed.

The vacuum envelope 10 thus formed is
Is cooled to room temperature in the cooling chamber 106 and then taken out of the unloading chamber 107. By the above process, FED
Is completed.

According to the FED and the method of manufacturing the same as described above, the front substrate 11 and the rear substrate 12 are sealed in a vacuum atmosphere, so that the surface of the substrate can be combined with baking and electron beam cleaning. The adsorbed gas can be sufficiently released, and the getter film is not oxidized, so that a sufficient gas adsorbing effect can be obtained. Thereby, an FED that can maintain a high degree of vacuum can be obtained.

Further, by using indium as a sealing material, foaming at the time of sealing can be suppressed, and an FED having high airtightness and sealing strength can be obtained.
At the same time, by providing the underlayer 31 under the indium layer 32, even when indium is melted in the sealing step, inflow of indium can be prevented and the indium can be held at a predetermined position. Therefore, handling of indium becomes simple, and even a large-sized image display device having a size of 50 inches or more can be easily and reliably sealed.

Further, by filling indium while applying ultrasonic waves, the wettability of indium to the sealing surface or the underlying layer 31 is improved, and even when indium is used as a metal sealing material, indium can be used in a desired manner. It is possible to fill the position well. Further, the molten indium can be continuously filled along the underlayer 31, so that an indium layer extending continuously along the underlayer can be formed. Furthermore, when the underlayer 31 is used as in the present embodiment, by filling the molten indium while applying ultrasonic waves, at the time of filling, a part of the indium diffuses into the surface portion of the underlayer 31. To form an alloy layer. Therefore, even when indium is melted at the time of sealing, the flow of indium can be more reliably prevented and held at a predetermined position. From the above, it is possible to obtain a method of manufacturing an image display device that can easily handle a metal sealing material and can easily and reliably perform sealing in a vacuum atmosphere.

In the above-described embodiment, the base layer 31 is provided on both the sealing surface of the front substrate 11 and the sealing surface of the side wall 18.
And in a state where the indium layer 32 is formed, but the sealing is performed only on one of the sealing surfaces, for example, as shown in FIG.
As shown in FIG.
The sealing may be performed in a state where the indium layer 32 is formed.

In the above-described embodiment, the underlayer is formed on the sealing surface, and the indium layer is formed thereon. However, the indium layer is directly formed on the sealing surface without using the underlayer. May be filled. Also in this case, by filling the molten indium while applying ultrasonic waves, the wettability of the indium to the sealing surface can be improved, and the desired position can be continuously and continuously filled with the indium.

In addition, the present invention is not limited to the above-described embodiment, but can be variously modified within the scope of the present invention. For example, the space between the rear substrate and the side wall may be sealed by a sealing layer in which the underlayer 31 and the indium layer 32 are fused as described above. Alternatively, one peripheral portion of the front substrate or the back substrate may be formed by bending, and these substrates may be directly joined without interposing a side wall. Furthermore, the indium layer is configured to have a width smaller than the width of the underlayer over the entire circumference, but if at least a portion of the underlayer is formed to have a width smaller than the width of the underlayer, It is possible to prevent the flow of indium.

In the above-described embodiment, a field emission type electron-emitting device is used as an electron-emitting device. However, the present invention is not limited to this, and other devices such as a pn-type cold cathode device or a surface conduction type electron-emitting device may be used. May be used. Further, the present invention is applicable to the manufacture of other image display devices such as a plasma display panel (PDP) and electroluminescence (EL).

[0066]

As described above in detail, according to the present invention, the sealing surface is filled with the molten metal sealing material while applying ultrasonic waves, and the substrates are sealed with the metal sealing material. Accordingly, it is possible to provide a manufacturing method capable of easily performing sealing in a vacuum atmosphere and manufacturing an image display device having high airtightness and sealing strength, and a sealing material filling device.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an FED according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1;

FIG. 3 is a plan view showing a phosphor screen of the FED.

FIG. 4 is a perspective view showing a state in which a base layer and an indium layer are formed on a sealing surface of a side wall and a sealing surface of a front substrate constituting a vacuum envelope of the FED.

FIG. 5 is a perspective view showing a sealing material filling device according to the embodiment of the present invention.

FIG. 6 is a perspective view showing a step of filling the sealing surface of the front substrate with indium by the sealing material filling apparatus.

FIG. 7 is a cross-sectional view showing a state in which a back-side assembly having a base layer and an indium layer formed on the sealing portion and a front substrate are opposed to each other.

FIG. 8 is a view schematically showing a vacuum processing apparatus used for manufacturing the FED.

FIG. 9 is a cross-sectional view showing a state in which a base layer and an indium layer are formed on a sealing surface of a front substrate in a step of forming a vacuum envelope of an FED according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Vacuum envelope 11 ... Front board 12 ... Back board 14 ... Support member 16 ... Phosphor screen 18 ... Side wall 22 ... Electron emission element 30 ... Low melting point glass 31 ... Underlayer 32 ... Indium layer 40 ... Support 42 ... Hot plate 44 ... Positioning mechanism 46 ... Filling head 48 ... Head moving mechanism 54 ... Reservoir 55 ... Nozzle 56 ... Ultrasonic vibration element 100 ... Vacuum processing device

Claims (12)

[Claims] 1. An image display device comprising: an envelope having a rear substrate, a front substrate opposed to the rear substrate, and a plurality of pixel display elements provided inside the envelope. In the manufacturing method, a step of filling a sealing surface between the rear substrate and the front substrate with a molten metal sealing material while applying ultrasonic waves, and after filling the metal sealing material, a vacuum atmosphere Wherein the metal sealing material is heated and melted therein, and the back substrate and the front substrate are directly or indirectly sealed with the sealing surface. Manufacturing method. 2. A rear substrate, a front substrate opposed to the rear substrate, and disposed between a peripheral portion of the front substrate and a peripheral portion of the rear substrate and sealed to the front substrate and the rear substrate. An envelope having a side wall, a plurality of pixel display elements provided inside the envelope,
A method for manufacturing an image display device, wherein at least one of a sealing surface between the front substrate and the side wall and a sealing surface between the rear substrate and the side wall is sealed with a metal sealing material layer. In the step of filling the at least one sealing surface with a molten metal sealing material while applying ultrasonic waves, after filling the metal sealing material, heating the metal sealing material in a vacuum atmosphere And bonding the back substrate, the front substrate, and the side wall with the sealing surface. 3. The step of filling the metal sealing material comprises continuously filling the molten metal sealing material along the sealing surface while applying ultrasonic waves, and extending along the sealing surface. 3. The method according to claim 1, further comprising the step of forming a metal sealing material layer. 4. In the step of filling the metal sealing material,
4. The method according to claim 1, wherein ultrasonic waves are applied in a direction substantially perpendicular to the sealing surface. 5. 5. The method according to claim 1, further comprising the step of forming an underlayer different from the metal sealing material on the sealing surface. After forming the underlayer, filling the metal sealing material on the underlayer. The method for manufacturing an image display device according to claim 1, wherein: 6. The image display device according to claim 5, wherein the underlayer is formed by applying a metal paste containing at least one of silver, gold, aluminum, nickel, cobalt, and copper. Production method. 7. The method according to claim 5, wherein the underlayer is formed of a metal plating layer or a deposited film containing at least one of silver, gold, aluminum, nickel, cobalt, and copper, or a glass material. Manufacturing method of an image display device. 8. In the step of filling the metal sealing material,
The discharge amount of the metal sealing material is controlled by any one of the oscillation output of the ultrasonic wave and the discharge hole diameter of the metal sealing material. Manufacturing method of an image display device. 9. The method according to claim 1, wherein the metal sealing material is a low melting point metal material having a melting point of 350 ° C. or less. 10. The method according to claim 9, wherein the low melting point metal material is indium or an alloy containing indium. 11. A vacuum envelope having a back substrate, a front substrate disposed opposite to the back substrate, and directly or indirectly sealed to the back substrate by a metal sealing material; A method of manufacturing an image display device, comprising: a phosphor screen formed on an inner surface of a substrate; and an electron emission source provided on the rear substrate and emitting an electron beam to the phosphor screen to emit light from the phosphor screen. Filling a sealing surface between the rear substrate and the front substrate with a molten metal sealing material while applying ultrasonic waves; and after filling the metal sealing material, the metal in a vacuum atmosphere. A method of heating and melting a sealing material, and directly or indirectly sealing the back substrate and the front substrate on the sealing surface. 12. A sealing material filling apparatus for filling a sealing surface with a metal sealing material in the method of manufacturing an image display device according to claim 1. A support base for positioning and supporting the sealed object having a storage portion storing the molten metal sealing material, a nozzle for filling the sealing surface with the molten metal sealing material sent from the storage portion, and A filling head having an ultrasonic generator for applying ultrasonic waves from the nozzle to the molten metal sealing material to be filled in the sealing surface, and a head for moving the filling head relative to the sealing surface A sealing material filling device, comprising: a moving mechanism.