JP3121200B2 - Method of manufacturing image display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a flat type image display device, and more particularly to a method of manufacturing a flat type image display device using a surface conduction electron-emitting device.

[0002]

2. Description of the Related Art Conventionally, a fluorescent display tube for forming an image, a plasma display, a display device using a field emission type Spindt type electron beam generator, and a display using a classical conventional surface conduction electron-emitting device. 2. Description of the Related Art An image display device such as a device that excites a phosphor and emits light for display has advantages such as being flat, bright and easy to see, and is actively applied and expected in industry.

As an example, FIG. 5 shows a conventional fluorescent display tube, and FIG.
FIG. 6 shows a conventional plasma display, and FIG.

The fluorescent display tube shown in FIG.
21 and a face plate 528 are arranged to face each other, and an insulating film 534 and an electrode 5 are provided on the rear plate 521.
22, 523, a phosphor 524, and a display portion 525 are provided. A transparent conductive film 529 is provided on a surface of the face plate 628 on the side of the rear plate 521, and a space between the rear plate 521 and the face plate 528 is provided. , A grid 526 and a filament 527 are provided.

In the plasma display shown in FIG. 6, a rear plate 621 and a face plate 628 are arranged to face each other. The rear plate 621 has a face plate 6
An electrode 623, an insulating film 634, and an electrode 622 are provided in order toward the 28 side, and a transparent conductive film 629 and a phosphor 624 are provided in order on the face plate 628 toward the rear plate 621 side.

In the fluorescent display tube and the plasma display shown in FIGS. 5 and 6, respectively, a rear plate 52 is provided.
1, 621 and the face plates 528, 628 are integrally sealed by frame members 533, 633 and sealing materials 532, 632. In the fluorescent display tube shown in FIG. 5, a lead 530 for transmitting an external signal is provided with a sealing material 5.
31 and connected to the electrode 522.

As a manufacturing method, a fluorescent display tube shown in FIG. 5 and a rear plate 5 of a plasma display shown in FIG.
21, 621, electrodes 522, 523, 622, 623,
The insulating films 534 and 634 are formed. In the fluorescent display tube shown in FIG. 5, a grid 526 serving as a control electrode, a filament 527, and the like are formed. Next, face plate 5
28, 628, transparent conductive films 529, 629, phosphor 52
4,624 and the like, and exhaust pipes 531 and 631 are formed in the frame members 533 and 633, and the rear plates 521 and 621 are formed.
And frame members 533, 633 and face plates 528, 6
28 are laminated via sealing materials 532 and 632, and heated and fired while applying pressure, whereby the rear plate 52
1, 621, face plates 528, 628, frame members 533, 633 and sealing materials 532, 632 form an envelope hermetically sealed.

Subsequently, the envelope formed as described above is sealed. FIG. 7 is a diagram showing a state in a heating step performed at the time of sealing.

As shown in FIG. 7, an image display device 736, which is an envelope manufactured as described above, is provided on a heating device 735.
Is evacuated from the exhaust pipe 731 while the image display device 736 is baked by the heating device 735 to form a desired degree of vacuum and atmosphere, and the exhaust pipe 731 is further heated, melted and sealed. Then, the image display device is manufactured.

[0010]

However, in the above-mentioned conventional method of manufacturing an image display device such as a fluorescent display tube or a plasma display, when the image display device is baked when the inside of the image display device is evacuated, This is a method of baking the exhaust pipe together with the image display device. After baking, the exhaust pipe is further heated to the melting temperature for sealing. For this reason, the interior of the exhaust pipe may be evacuated to a desired atmosphere by evacuating the exhaust pipe in a state where the exhaust pipe is not sufficiently baked, and the exhaust pipe may be sealed. The following problems occur.

(1) Since the degree of vacuum inside the image display device is reduced due to outgas from the exhaust pipe, the withstand voltage of the high voltage applied between the rear plate and the face plate is reduced, and discharge and the like are caused inside. Occurs, and the device is deteriorated and destroyed. In addition, an extremely thin planar image display device in which the distance between the rear plate and the face plate is reduced, and a planar image display device that requires a high voltage to form a high-luminance light-emitting portion. Such a problem is remarkable in the device.

(2) Since the atmosphere inside the image display device changes due to the outgas from the exhaust pipe, the driving start voltage of the device changes and the durability deteriorates.

Due to the above problems, when the image display device is driven and operated, not only does the quality of the displayed image deteriorate with the lapse of time, but also abnormal discharge and the like occur. There is a problem of failure.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has been made capable of improving the image quality of an image display device by making sufficient outgassing during evacuation. It is an object of the present invention to realize a method of manufacturing an image display device having a long life.

[0015]

According to the present invention, there is provided a method of manufacturing an image display device, comprising: an exhaust pipe inserted into the outside; an envelope in which an image display member is provided; A first step of baking while evacuating through the first step;
And a second step of sealing the exhaust pipe in order to maintain the internal space in a vacuum after the vacuum exhaust is performed in the step of: baking the exhaust pipe in the first step. The temperature is higher than the baking temperature of the envelope
And the temperature is lower than the softening point of the exhaust pipe. In the second step, the exhaust pipe heated in the first step is heated and sealed.

[0016]

[0017]

In the present invention, the baking performed while evacuating in the first step is performed not only for the envelope but also for the exhaust pipe, and the baking temperature at this time is higher than the baking temperature for the envelope. Therefore, the degree of vacuum inside the image display device does not decrease and the atmosphere does not change due to outgas when the exhaust pipe is sealed.

If the temperature of the exhaust pipe is higher than the softening point of the exhaust pipe, the exhaust pipe is deformed and hinders the subsequent sealing work. However, when the temperature of the exhaust pipe is close to the softening point and lower than the softening point, Outgassing can be minimized, and the easiness of the sealing operation can be prevented from being impaired.

[0019]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing the structure of an image display device manufactured by the manufacturing method of the present invention.

In FIG. 1, reference numeral 106 denotes the transparent conductive film 10.
7, a face plate 101 on which a phosphor 108 and a metal back 109 are formed, and an insulating plate 101 on which a plurality of electron beam generators each including an element electrode 104 and a fine particle film 105 provided between the element electrodes 104 are formed. It is a rear plate composed of a base, and forms an image display member together with the face plate 106. The rear plate 101 has the above-described plurality of electron beam generators mounted thereon via a control electrode 102 and an insulating layer 103. Reference numeral 111 denotes a frame member for forming an envelope, which is welded to the face plate 106 and the rear plate 101 via a sealing material 112 to form an envelope. Reference numeral 110 denotes an exhaust pipe for evacuating, which is inserted through the frame member 111 into the envelope.

The frame member 111, the rear plate 101, and the face plate 106 in the method of manufacturing an image display device of the present invention may be made of any material having an insulating property. It is preferable to select materials so that the thermal expansion coefficients are substantially the same.
In particular, if specific examples of the material are given, a blue plate,
Examples include a glass substrate such as quartz and a ceramic substrate such as Al ₂ O ₃ .

The sealing material 112 is used for the rear plate 101.
Any material may be used as long as the material and the face plate 106 can be hermetically sealed via the frame member 111. Among them, particularly, specific examples of the material include amorphous low-melting point frit glass, crystalline low-melting point frit glass, and the like, and mixing them with an organic solvent, a binder such as nitrocellulose, and the like. An organic solvent that dissolves the binder is mixed to prepare a paste, and a paste that is tacky at least at the application temperature of the sealing material 112 is used. Needless to say, a sealing material prepared according to the application method is used.

The method of applying the sealing material 112 may be any method such as a printing method, a spray method, a dispenser method, or the like, as long as a desired amount of the sealing material can be applied and formed.

Next, as shown in the figure, a sealing material 112 is formed on the rear plate 101 on which the electron beam generator is formed, and a frame member 111 is disposed above the sealing material 112.
A sealing material 112 is formed above the sealing material 11, and a face plate 106 is further disposed above the sealing material 112, and a temperature at which the low melting point frit glass used for the sealing material 112 melts, for example, in a range of about 350 ° C. to 650 ° C. It is heated at the internal temperature to be welded. Further, if necessary, pressure is applied from the face plate 106 or the rear plate 101 side. Thereafter, heating is performed using the heating device shown in FIG. 2 or FIG.

Next, the heating step in this embodiment will be described with reference to FIGS.

In FIGS. 2 and 3, reference numeral 214 denotes a display device configured as shown in FIG.
Reference numeral 15 denotes an exhaust pipe heating device.

In the heating step, the display device 214 formed by the rear plate 101, the face plate 106 and the frame member 111 is heated by the heating device 213 as shown in FIGS. The inside of the display device 214 is evacuated from the inside exhaust pipe 110) and evacuated to a desired vacuum.

The heating method includes a display device 214 and an exhaust pipe 21.
As long as the heating temperature of 0 is almost the same, any apparatus or method may be used as long as it can be heated to a desired temperature, such as a baking furnace, an infrared heater, and a hot plate.

In order to heat the exhaust pipe 210 at a higher temperature than the display device 214, the exhaust pipe heating device 3 shown in FIG.
Using 15 heat to the desired temperature.

As the exhaust pipe heating device 315, a winding heater, a ribbon heater, induction heating, or the like can be used, but any device or method may be used as long as it can heat at a desired temperature. .

The heating temperature of the display device 214 and the exhaust pipe 210 is in a range where the exhaust gas at the time of sealing the exhaust pipe 210, the degree of vacuum caused by the outgas from the inside of the display device 214 after the sealing, and the change in atmosphere are small. The heating may be performed at a temperature, for example, at a temperature within a range from about 120 ° C. to the softening point of the exhaust pipe or lower. By setting the temperature near the softening point of the exhaust pipe, it is possible to reduce outgas when the exhaust pipe is melted and sealed later.

If the temperature of the exhaust pipe is higher than the softening point of the exhaust pipe, the exhaust pipe is deformed and hinders the subsequent sealing operation. By doing so, the generation of outgas can be minimized, and the easiness of the sealing operation can be prevented from being impaired.

Next, the exhaust pipe 21 which has been sufficiently heated and exhausted is used.
0 is heated, melted and sealed to produce an image display device.

As described above, according to the manufacturing method of the present invention, the vacuum sealing of the image display device with less outgas when the exhaust pipe 210 is sealed is performed.

The electron beam generator formed on the rear plate 101 shown in FIG. 1 includes a fluorescent display tube using a filament-like thermoelectron source, a plasma display using discharge, and a bulk type thin film. There is a cold cathode device classified into a type.

For example, as an example of a bulk type, FE [W.
P. Dyke & W. W. Dolan, "Field
Emission ", Advance in Ele
ctron Physics, 8, 89 (1956)]
And Avalanche type and NEA type semiconductors [J. A. Burton, "Electron Emi
session from silicon ", Phys.
Rev .. , 108, 1342 (1957)] or M
gO ["Tung-sol confirmsmould"
cathode tube ", Electronicic
s News (26, Jan. 1959)], and a photocathode and the like are known.

On the other hand, as an example of a thin film type, MIM [C.
A. Mead, "The tunnel-emissi
on amplifier ", J. Appl. Phys.
s. , 32, 646 (1961)] and Spindt type [C. A. Spindt, "Physical pro
parties of thin-film field
demission cathodes with m
olybdenum cones ", J. Appl. P
hys. , 47, 5248 (1976)] or a surface conduction electron-emitting device [M. I. Elinson, Rad
io Eng. Electron Phys. , 10,
(1965)].

The surface conduction electron-emitting device utilizes a phenomenon in which electrons are emitted by passing a current through a small-area thin film formed on a substrate in parallel.

As the surface conduction electron-emitting device, a device using a SnO ₂ (Sb) thin film developed by Elinson and others, a device using an Au thin film [G. Dittm
er: “Thin Solid Films”, 9, 3
17 (1972)], using an ITO thin film [M. Ha
rtwell and C.I. G. FIG. Fonstad: "I
EEE Trans. ED Conf. ", 519 (1
975)], 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.

In Japanese Patent Application Laid-Open Nos. 1-200532 and 2-56822, a surface conduction electron-emitting device in which a fine particle film is arranged between electrodes and an electron-emitting portion is formed by applying a current to the fine-particle film. It is shown. Any of these electron generating devices may be used.

Next, the manufacturing process according to the present invention will be described with reference to FIG.
This will be described more specifically with reference to FIGS.

Reference Example 1 The image display device shown in FIGS. 1 and 2 was produced as follows.

After using a blue plate glass as the rear plate 101 and sufficiently washing it with an organic solvent, a vacuum evaporation technique,
The control electrode 10 is formed by photolithography technology.
2. An insulating layer 103 was formed. Subsequently, FIG.
As shown in the top view and the front view of (b), an element electrode 104 made of Ni was formed. At this time, the element electrode interval L
₁ was 3 μm, the width W _{1 of the} device electrode was 500 μm, and its thickness d was 1000 °.

(2) Next, a solution containing an organic palladium (ccp-4230, manufactured by Okuno Pharmaceutical Co., Ltd.) was applied to a predetermined portion, followed by a heat treatment at 300 ° C. for 10 minutes to obtain palladium oxide (PdO). 3.) A fine particle film 105 composed of fine particles (average particle size: 70 °) was formed. Its width (element width) W
Was set to 300 μm, and it was arranged almost at the center of the device electrode.
The film thickness was 100 ° and the sheet resistance was 5 × 10 ⁴ Ω /
It was □.

The fine particle film described here is a film in which a plurality of fine particles are gathered, and has a fine structure not only in a state in which the fine particles are individually dispersed and arranged, but also in a state in which the fine particles are adjacent to each other or overlap each other (an island). The particle size refers to the diameter in a state where the particle shape can be recognized in the above state.

(3) Next, a soda lime glass was used as the frame member 111, an exhaust hole was formed at a predetermined position, and an exhaust pipe 110 made of a soda lime glass was fused and formed.

(4) Next, a low-melting glass (LS-3081, manufactured by Nippon Electric Glass Co., Ltd.) and ethyl cellulose are applied to the surfaces of the frame member 111, which are in contact with the rear plate 106 and the face plate 101, respectively, using a dispenser. A solution obtained by dissolving in a solvent was applied and formed.

(5) Next, the rear plate 101 on which the electron beam generator is formed, the frame member 111, and the face plate 106 are arranged and laminated at predetermined positions, and pressurized with a 1 kg weight from above, and Sealing heat treatment temperature 410
The resultant was fired under the conditions of ° C and a sealing heat treatment time of 60 minutes to form an image display device.

(6) Next, 1 × 10 ⁻⁶ from the exhaust pipe 110.
By evacuating to about torr, applying a voltage between the element electrodes 104 and applying a current to the fine particle film 105 (forming process), the electron emission portion 401 (see FIG. 4)
Was prepared.

Further, the surface conduction type electron discharge used in the present invention is used.
In detail, the fine particle film containing the electron emission material
105 is a conductive fine particle having a particle size of more than ten
Particles or a carbohydrate in which these conductive fine particles are dispersed
Thin film. In particular, the specifics of the material
For example, Pd, Ag, Au, Ti, In, C
gold such as u, Cr, Fe, Zn, Sn, Ta, W, Pb
Genus; PdO, SnO_Two, In_TwoO_Three, PbO, Sb_TwoO_ThreeWhat
Which oxide conductor; HfB_Two, ZrB_Two, LaB ₆, Ce
B₆, YB_Four, GdB_FourBorides such as TiC, ZnC,
Carbides such as HfC, TaC, SiC, WC; TiN;
Nitrides such as ZrN and HfN; semiconductors such as Si and Ge
Body; carbon; AgMg; NiCu; PbSn, etc.
You. These films are formed by vacuum evaporation, sputtering,
Vapor deposition, dispersion coating, dipping, spinner
It is formed by a method or the like.

Further, as a structure of the control electrode 102, in addition to a structure formed and controlled on the back surface of the electron beam generating portion as described in this embodiment, an electron passage hole is provided above the electron beam generating portion. And a simple matrix structure.

(7) Next, as shown in FIG. 2, the display device 214 manufactured as described above was heated using a baking furnace as the heating device 213, and the display device 214 and the exhaust pipe 210 were heated at a heat treatment temperature of 200 ° C. Exhaust pipe 2 under the condition of time 10 hr
Heat treatment was carried out while evacuating from 10, and the exhaust pipe 210 was heated, melted and sealed to form an image display device.

In the image display device manufactured as described above, since the device 214 and the exhaust pipe 210 are heat-treated at the same temperature and outgassing is performed, it is necessary to reduce outgassing when the exhaust pipe 210 is sealed later. Display device 21
4 An image display device could be formed without lowering the degree of vacuum inside.

When this image display device was driven and operated, the rear plate 101 and the face plate 10
No high-voltage discharge was applied to Sample No. 6, and an image display device excellent in durability was obtained.

Embodiment 1 Next, a case where the exhaust pipe 210 is heated at a higher temperature than the display device 214 will be described with reference to FIG.

In the case of this embodiment, a hot plate is used for the heating device 213, and the exhaust pipe 210 is connected to the exhaust pipe heating device 215.
A display device 214 was manufactured in the same manner as in Reference Example 1 except that the manufacturing method was such that a heat treatment was performed. Further, a winding heater was used for the exhaust pipe heating device 215.

In this embodiment, the heat treatment temperature of the display device 214 is 160 ° C., and the heat treatment temperature of the exhaust pipe 10 is 300 ° C.
C. and a heat treatment time of 8 hours.

[0059] As a result, the heat treatment temperature of the display device 214 despite lower than Reference Example 1, the same effect as in Reference Example 1 was confirmed.

Reference Example 2 In this example, the display device was a fluorescent display tube using a filament. In addition, a heat treatment temperature of 350 ° C. and a treatment time of 1
An apparatus was manufactured in the same manner as in Reference Example 1 except that the time was changed to hr (not shown).

As a result, the same effect as in Reference Example 1 was confirmed despite the difference in the electron beam generator formed on the rear plate and the heat treatment temperature and treatment time.

Embodiment 2 In this embodiment, the display device has a structure using a plasma generator. Further, an apparatus was manufactured in the same manner as in Example 1 except that the heat treatment temperature of the apparatus was 300 ° C., the heat treatment temperature of the exhaust pipe was 400 ° C., and the treatment time was 2 hours (not shown).

As a result, the same effect as in Example 1 could be confirmed despite the difference in the electron beam generator formed on the rear plate, the heat treatment temperature and the treatment time.

REFERENCE EXAMPLE 3 In this reference example, except that the device and the exhaust pipe were subjected to a heat treatment, a voltage was applied to the element electrodes, and the fine particle film was subjected to a conduction treatment (forming treatment) to form an electron-emitting portion. Reference Example 1
A device was produced in the same manner as described above (not shown).

As a result, the same effect as in Reference Example 1 could be confirmed despite the difference in the manufacturing process between the heat treatment and the energization treatment.

(Embodiment 3 ) In this embodiment, the device and the exhaust pipe are subjected to heat treatment, the exhaust pipe is sealed, a voltage is applied to the element electrode, and the fine particle film is subjected to an energizing treatment (forming treatment) to emit electrons. An apparatus was manufactured in the same manner as in Example 1 except that a portion was formed (not shown).

As a result, the same effect as in Example 1 was confirmed despite the difference in the manufacturing method between the heat treatment and the current application.

Example 4 In this example, an apparatus was manufactured in the same manner as in Example 1 except that a ribbon heater was used for the exhaust pipe heating device 215 (not shown).

As a result, the same effect as in Example 1 could be confirmed despite the difference in the exhaust pipe heating device 215.

Example 5 In this example, a device was produced in the same manner as in Example 1 except that a high-frequency induction heating device was used as the exhaust pipe heating device 215 (not shown). In this embodiment, the frequency of the high-frequency induction heating device is set so that the entire exhaust pipe 210 can be heated.

As a result, the same effect as in Example 1 was confirmed despite the difference in the exhaust pipe heating device 215.

In the present embodiment, it is possible to heat only specific gas molecules by adjusting the set frequency. Therefore, it is possible to select the type of gas to be outgased when sealing the exhaust pipe 210, and it is possible to perform a fine sealing operation according to the materials of the constituent members such as the exhaust pipe and the sealing material. effective.

[0073]

Since the present invention is configured as described above, it has the following effects.

After the baking temperature of the exhaust pipe is equal to or higher than the baking temperature of the apparatus, the image display apparatus is manufactured by the step of sealing the exhaust pipe. (1) The degree of vacuum and atmosphere inside the apparatus Can be sealed without reduction. (2) Deterioration of the device due to high-voltage discharge and the like is reduced, and the yield is improved. (3) The change of the driving voltage of the device and the deterioration of the durability are reduced,
This has the effect of improving the quality stability of the device and extending the life.

Further , since the generation of outgas can be minimized and the easiness of the sealing operation can be prevented from being impaired, each of the above effects can be further improved. .

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of an example of an image display device manufactured by a manufacturing method of the present invention.

FIG. 2 is a schematic cross-sectional view showing one example of the manufacturing method of the present invention.

FIG. 3 is a schematic sectional view showing another example of the manufacturing method of the present invention.

FIGS. 4A and 4B are a top view and a front view, respectively, of an electron beam generator manufactured by the present invention.

FIG. 5 is a schematic partial sectional view of an example of an image display device manufactured by a conventional method.

FIG. 6 is a schematic partial sectional view of another example of an image display device manufactured by a conventional method.

FIG. 7 is a schematic cross-sectional view showing one example of a conventional manufacturing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Rear plate 102 Electrode 103 Insulating layer 104 Element electrode 105 Fine particle film 106 Face plate 107 Transparent conductive film 108 Phosphor 109 Metal back 110 Exhaust pipe 111 Frame member 112 Sealing material 210 Exhaust pipe 213 Heating device 214 Display device 315 Exhaust pipe heating Device 401 electron emission unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B01J 9/40 B01J 9/39 B01J 31/12 B01J 31/15

Claims (1)

(57) [Claims] A first step of baking an envelope provided with an image display member therein while evacuating the envelope via the exhaust pipe, the method comprising: A second step of sealing the exhaust pipe in order to maintain the internal space in a vacuum after the first exhaustion is performed in the first step. Is higher than the baking temperature of the envelope and equal to or lower than the softening point of the exhaust pipe. In the second step, the exhaust pipe heated in the first step is heated and sealed. A method for manufacturing an image display device, comprising: