JP2003109521A - Display panel and its sealing method and image display device having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable to adopt different kinds of glass material that have a difference of the thermal expansion coefficient of more than 2×10<-7> / deg.C in the rear plate and face plate. SOLUTION: This is a display panel in which an outer case 90 is formed of a rear plate 81 and a face plate which are arranged opposed to each other and a support frame 86 of which on one end the face plate 82 is jointed and on the other end the rear plate 81 is jointed. The face plate 82 and one end of the support frame 86 are jointed by a jointing member 206 that has a melting point at a prescribed temperature and also has elasticity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display panel in which a vacuum envelope is formed by joining glass members and a method for sealing the display panel. Furthermore, the present invention relates to an image display device provided with such a display panel.

[0002]

2. Description of the Related Art As an electron source of this type of display panel,
Two types of thermoelectron sources and cold cathode electron sources are known. The cold cathode electron source is a field emission device, a metal / insulating layer / metal device, a surface conduction electron emission device (hereinafter abbreviated as SCE device).
Etc. As an example, a conventional display panel using an electron source substrate in which SCE elements are arranged in a matrix is shown in FIG.

Referring to FIG. 20, this display panel is
A rear plate 81 having an electron source substrate 80 on one surface of which a large number of electron-emitting devices 87, which are surface-conduction electron-emitting devices (hereinafter abbreviated as SCE devices), are arranged in a matrix, and a fluorescent film 84 on the inner surface of a glass substrate 83. A face plate 82 formed with a metal back 85 and the like is arranged so as to be opposed to each other via a support frame 86. The rear plate 81, the support frame 86, and the face plate 82 are adhered to each other by frit glass, and the vacuum envelope 90 is sealed by firing at 400 to 500 ° C. for 10 minutes or more. On the electron source substrate 80, an X-direction wiring 88 and a Y-direction wiring 89 connected to the pair of element electrodes of the SCE element 87 are formed.

The envelope 90 is joined at a temperature such that the frit glass material is melted and the fluidity is increased, so that the envelope 9 is sealed.
The vacuum inside 0 is maintained. By performing a series of manufacturing steps of the envelope 90 in a vacuum chamber, the envelope 90
The inside can be evacuated from the beginning, and the manufacturing process becomes simple. Further, by installing a support body (not shown) called a spacer between the face plate 82 and the rear plate 81, the envelope 90 having sufficient strength against atmospheric pressure is configured even in the case of a large area panel. can do.

In the above-mentioned display panel, when the element voltage Vf of several tens of V is selectively applied between the element electrodes of the SCE element 87 via the X-direction wiring 88 and the Y-direction wiring 89, SCE
Electrons are emitted from the element 87. The emitted electrons reach the face plate 82, which is an anode to which a voltage of several kV is applied, via the high-voltage terminal Hv, and the fluorescent film 84.
The fluorescent substance of is made to emit light. An image is displayed by controlling the light emission of the phosphor on the face plate 82.

In the sealing structure such as the display panel shown in FIG. 20, the rear plate 81 and the face plate 82 are
The same kind of glass material is used to have the same coefficient of thermal expansion. Further, as the frit glass used for adhesion, one having a substantially equal coefficient of thermal expansion is selected according to the glass material used for the plates. This is because when different kinds of glass materials having different thermal expansion coefficients are used, the amount of shrinkage differs in the process of cooling the glass substrate expanded at the above-mentioned bonding temperature to room temperature, and as a result, the glass material can be easily prepared. This is because the vacuum cannot be maintained due to breakage or cracks. Generally, the difference in expansion coefficient between two materials to be sealed is about 2 × 10.
^-7 / ° C or less is considered optimal.

[0007]

In the conventional display panel described above, the rear plate 81 and the face plate 8 are provided.
2 originally has a different function as a required glass material. Therefore, there are the following problems.

As the glass material used for the rear plate 81, it is common to use inexpensive soda lime glass,
Usually, a substrate in which a 0.5 μm-thick silicon oxide film is formed as a sodium block layer on a soda-lime glass substrate by a sputtering method is used. However, judging the performance (characteristics) of the electron-emitting device based on the electron emission efficiency and durability,
Generally, it is considered that a quartz substrate or a non-alkali substrate has better performance of the electron-emitting device, and in consideration of this, the rear plate 81 does not contain a small amount of sodium ions (= a small amount of alkali). It is desirable to use an alkali glass material.

On the other hand, the face plate 82 is, of course, inexpensive in raw material, but has a high electric resistance.
It is required that there be little coloring by electron beams or X-rays. Therefore, silicic acid (SiO 2
2) It is desirable to use a glass for a television picture tube in which the content is suppressed to 70% or less and the total content of BaO and Li ₂ O is 10% or more.

Further, after the electrons emitted from the electron source substrate are incident on the face plate 82 and part of them become reflected electrons and hit the inside of the panel, soft X-rays are generated, but these soft X-rays are harmful to the human body. , It is necessary to prevent leaking out of the panel. Therefore, the face plate 82
It is also required to prevent X-ray leakage. The above-mentioned glass for a television picture tube can prevent such leakage of soft X-rays. Little coloring, sufficient X
Recently, PDH glass materials used for plasma displays have been proposed as a material that can obtain a line-shielding effect.

Based on the above requirements, the rear plate 8
It is desirable to use a non-alkali glass material for No. 1 and use PDP glass or television picture tube glass for the face plate 82. However, when comparing these glass materials in terms of coefficient of thermal expansion, the alkali-free glass material is about 40 × 10 ⁻⁷ / ° C. and the glass for PDP is about 80 × 10 7.
^-7 / ℃, glass for TV picture tube is about 100 × 10
^-7 / ° C, and in the case of the above combination using these glass materials, the rear plate 81 and the face plate 82
Since the difference in coefficient of thermal expansion between the two becomes large, cracks easily occur in the conventional sealing structure.

Further, by using non-alkali glass for both the rear plate 81 and the face plate 82 and increasing the thickness of the non-alkali glass on the face plate 82 side, the electron-emitting device has good performance and shields X-rays. However, in this case, in order to suppress X-ray leakage, the face plate 82 can be provided.
Since it is necessary to make the plate thickness of the device unnecessarily large, there arises a problem that the device weight increases and the cost also increases. here,
When the substrate is formed as a part of a container, the thickness more than necessary means that the thickness is not less than a plate thickness that is appropriately set depending on mechanical conditions such as an atmospheric pressure resistant structure for holding the container in a vacuum. It is necessary.

The object of the present invention is to solve the above-mentioned problems, and even if a different glass material having a difference in coefficient of thermal expansion exceeding 2 × 10 ⁻⁷ / ° C. is used for the rear plate and the face plate, cracks and other defects occur. It is an object of the present invention to provide a display panel that does not generate the light and a method for sealing the display panel.

Another object of the present invention is to provide an image display device provided with such a display panel.

[0015]

In order to achieve the above object, a display panel of the present invention is a display panel in which a vacuum envelope is formed by joining first and second plates facing each other. In the above, the first and second plates are joined by a joining member having a melting point at a predetermined temperature and having elasticity.

The method for sealing a display panel according to the present invention is a method for sealing a display panel in which a vacuum envelope is formed by joining first and second plates arranged to face each other,
A joining member having a melting point and elasticity at a predetermined temperature is provided at a joining portion of the first and second plates, and the joining member is melted to join the joining portion. .

The display panel sealing method of the present invention is
The first and second plates arranged to face each other and the first plate are joined to the end surface on one side,
In a method for sealing a display panel in which a vacuum envelope is formed by a plate and a supporting frame joined to the end face on the other side, the second plate and the end face on the other side of the supporting frame are joined together. After that, a joining member having a melting point and elasticity at a predetermined temperature is provided at a joining portion between the first plate and the end surface on one side of the supporting frame, and the joining member is melted to form the joining member. It is characterized in that the joint portion is joined.

An image display device of the present invention is characterized by including the above display panel and a drive circuit for supplying a drive voltage to the display panel to display an image.

Conventionally, heat treatment was performed at 400 to 500 ° C. for joining, whereas in the present invention as described above, the heating temperature at the time of joining may be a temperature at which the joining member melts. For example, the heating temperature of the joining member made of In is 180 ° C. As described above, in the present invention, since the heating temperature is lower than the conventional temperature, the first plate (here, the face plate) and the second plate (here, the face plate) in the cooling process after heating (the process until the temperature drops to room temperature). Here, the stress caused by the difference in the coefficient of thermal expansion of the rear plate) becomes smaller as the heating temperature becomes lower.

In addition, since the joining member has elasticity at room temperature, the elasticity can absorb the stress caused by the difference in the thermal expansion coefficient of the first and second plates in the cooling process after the heat treatment. Therefore, as long as the stress can be absorbed by the elasticity, even if the first and second plates having different thermal expansion coefficients are selected, a crack or the like does not occur.

From the above, according to the present invention,
It is possible to select a material with a good electron-emitting device performance for the rear plate and a material with a high electrical resistance for the face plate, less coloring due to electron beams and X-rays, and a material that can prevent X-ray leakage. Become.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
FIG. 6 is a diagram for explaining the structure of the display panel of the embodiment of
(A) is a perspective view in which a part of the panel is cut away, and (b) is an enlarged cross-sectional view of a broken line portion a of the panel shown in (a).

As shown in FIG. 1A, the panel of this embodiment includes a rear plate 81, a face plate 82 arranged to face the rear plate 81, and a support frame 86 for supporting these plates. An envelope 90 made of The rear plate 81 has a large number of electron-emitting devices 87, which are SCE devices, arranged in a matrix.
A pair of element electrodes of the element 87 has an electron source substrate 80 connected to the X-direction wiring 88 and the Y-direction wiring 89 on one surface. The face plate 82 is composed of a glass substrate 83 having a fluorescent film 84, a metal back 85 and the like formed on the inner surface.
The rear plate 81, the support frame 86, and the face plate 82 are almost the same as those shown in FIG. 20, but the sealing structure of the envelope 90 is different.

The sealing structure of the envelope 90 will be specifically described below with reference to FIG.

The supporting frame 86 is adhered to the rear plate 81 by the frit glass 203, and the supporting frame 86 is kept at 400 to 500 ° C.
It is fixed by firing for 0 minutes or more. The support frame 86 and the face plate 82 are bonded by the joining member 206. As the joining member 206, a relatively soft member (having a high extensibility) so as to absorb the difference in the coefficient of thermal expansion between the rear plate 81 and the face plate 82,
Alternatively, a material having a large elasticity) and which emits little gas even at high temperature is used. Since metals and alloys do not contain a solvent or a binder, the amount of released gas when they melt out at the melting point is very small, which is desirable as a joining member. In this embodiment,
Metal In having a low melting point is used for the joining member 206.

An undercoat layer 204 is provided at a position where the supporting frame 86 and the face plate 82 are bonded to each other by the joining member 206 in order to enhance the adhesiveness at the interface. In the present embodiment, as the undercoat layer 204, silver having good wettability with respect to the metal In used for the joining member 206 is used. When silver is used, there is an advantage that the undercoat layer 204 can be easily patterned by screen printing using a silver paste. In addition, as the undercoat layer 204, when metal In is used for the bonding member 206, a metal thin film such as ITO or Pt that can be easily formed by a vacuum deposition method is sufficient.

A height defining member 205 is provided adjacent to the support frame 86 in order to maintain the joining member 206 at a predetermined thickness. One end of the height regulating member 205 is bonded and fixed to the rear plate 81 by the frit glass 203,
The other end is abutted against the face plate 82, and the thickness (length from one end to the other end) of the support frame 8
Thicker than that of 6. Due to this difference in thickness, the joining member 2
A thickness of 06 can be specified. In this embodiment,
The thickness of the height defining member 205 is set so that the thickness of the joining member 206 is 300 μm. Height regulating member 2
As 05, similarly to the support frame 86, glass of the same kind as the rear plate 81 or a material having the same thermal expansion coefficient can be used. The height regulating member 205 can be fixed to the rear plate 81 in the same heat treatment process as the supporting frame 86 is fixed to the rear plate 81, and thus the manufacturing process can be simplified.

When manufacturing the panel of this embodiment having the above-described sealing structure, first, the support frame 86 and the height defining member 205 are fixed to the rear plate 81, and then the support frame 86.
The envelope 90 is formed by sealing the space between the face plate 82 and the face plate 82 with the joining member 206. Joining member 20
Since the melting point of the metal In used for No. 6 is as low as 156 ° C., in this panel, while applying a predetermined pressure to the joining member 206 from both sides of the face plate 82 side and the rear plate 81 side, The supporting frame 86 and the face plate 82 are joined by the joining member 206 by performing a heat treatment at 10 ° C. for about 10 minutes. At the time of this bonding, the metal In is melted by the heat treatment and the fluidity is increased, and as a result, the vacuum inside the envelope 90 is maintained. By performing all of this series of steps in the vacuum chamber, the inside of the envelope 90 can be simultaneously evacuated from the beginning, and the steps can be simplified.

According to the panel sealing structure of the present embodiment described above, the heating temperature at the time of joining is as low as 180 ° C., whereas the heating treatment at the temperature of 400 to 500 ° C. has been conventionally used for joining. Cooling process after heating (process until the temperature drops to room temperature)
At the face plate 82 and the rear plate 81
The stress caused by the difference in the coefficient of thermal expansion of is reduced as the heating temperature is lowered. In addition, since the joining member 206 has extensibility, in the cooling process after the heat treatment,
The joining member 206 itself absorbs the stress caused by the difference in thermal expansion coefficient between the face plate 82 and the rear plate 81. Therefore, if the face plate 82 and the rear plate 81 having different thermal expansion coefficients are selected within a certain range, a defect such as a crack does not occur. The absorption of stress by the joining member 206 is greatly affected by the thickness of the joining member 206.

Further, since the height regulating member 205 regulates the thickness of the panel (the distance between the face plate 82 and the rear plate 81), the joining member 20 is joined at the time of joining.
6 is maintained at a predetermined thickness and does not collapse.
It is desirable that the height regulating member 205 be provided near the support frame 86. In the structure shown in FIG. 1B, the height defining member 205 is provided inside the envelope 90.
The height regulating member 205 may be provided outside the envelope 90.

Further, also in the panel of this embodiment,
By installing a support body (not shown) called a spacer, it is possible to configure the envelope 90 having sufficient strength against atmospheric pressure even in the case of a large area panel. In that case, the height defining member A structure in which 205 also serves as such a spacer may be adopted.

Next, the materials and characteristics of each member constituting the envelope of the panel of this embodiment will be described in more detail.

FIG. 2 shows device materials in the optical and electronic fields.
A set of representative glass substrates used as
And the coefficient of thermal expansion. As mentioned above, different materials
When lath is sealed with frit glass, etc.
Is about 2 × 10 ^-7/ ° C or below is considered optimal
Therefore, any of the glass materials in FIG. 2 has been conventionally used.
It was also said that the combination of was not suitable. On the contrary,
According to the panel sealing structure of the present embodiment, as described above,
Due to the joining member 206 having a low melting point and ductility
It has been a problem until now due to the joining structure
Shadow of difference in coefficient of thermal expansion between plates made of different glass materials
A structure that is less susceptible to noise is realized. Therefore, this embodiment
In the state, the face plate 81 and the rear plate 82 are swollen.
The difference in tension coefficient is about 2 × 10^-7For glass materials exceeding / ° C
Can be For example, as the joining member 206, In
When using a
Uses non-alkali glass material used as lath
The face plate 82 for plasma display.
PDH glass used, for example, low alkali content
The material of PD-200 (made by Asahi Glass Co., Ltd.) is used.
be able to.

The lower the melting point of the joining member 206, the less likely it is to be affected by the difference in the coefficient of thermal expansion between the plates. For example,
When In is used for the joining member 206, the maximum joining length in the longitudinal direction of the support frame 86 is 300 mm, and the difference in coefficient of thermal expansion between the face plate 82 and the rear plate 81 is 40.
In the case of × 10 ⁻⁷ / ° C., the difference in shrinkage amount between the face plate and the rear plate, which occurs when cooling from the melting point of In of 156 ° C. to room temperature of 25 ° C., is about 150 μm. On the other hand, in the case of a joining member having a melting point of 300 ° C., the difference in shrinkage amount between the face plate and the rear plate during the cooling process from 300 ° C. to room temperature 25 ° C. is about 300 μm, which is twice that. Become.

Further, the joint member 206 deforms by itself to absorb the difference in shrinkage amount between the plates made of different glass materials. By using a highly stretchable (highly elastic) material such as In for the joining member 206, it is possible to absorb a larger difference in shrinkage amount. Note that when a hard material having a small stretchability is used for the joining member 206, the amount that can absorb the difference in the shrinkage amount between the plates is also small.

The thickness of the joining member 206 itself greatly affects the absorption of the difference in shrinkage amount by the joining member 206. As an example, the envelope 9 when In is used for the joining member 206
The performance result of 0 is shown in FIG.

In FIG. 3, the horizontal axis represents the maximum joint length (nm) in the longitudinal direction of the support frame 86, and the vertical axis represents the height defining member 205.
Is the thickness of the joining member 206 defined by. The maximum joint length varies depending on the size of the envelope 90. Figure 3
Inside, "○" indicates that the envelope 90 could be formed as a vacuum box, "△" indicates that a leak occurred, and "X".
Indicates that the face plate 82 has cracked.

As can be seen from the result of FIG. 3, the envelope 90
If the size is small, it is possible to form a vacuum box with plates made of different glass materials relatively easily by simply adopting a sealing structure that is joined by In. If the thickness becomes large, the difference in the coefficient of thermal expansion between different kinds of glasses cannot be absorbed unless the thickness of In is sufficient, and cracks occur in the plate. Therefore, as the size of the envelope 90 increases, the thickness of In also needs to increase accordingly. Experimentally, the In thickness is preferably 0.01 to 1% of the maximum junction length, and more preferably 0.05 to 0.5%.

From the results of the experiments so far, for example, a Sn / Ag type solder material having a melting point of 250 ° C. was used as the joining member 20.
When used as No. 6, it is known that the maximum joining length is 300 mm and the joining member 206 needs to have a thickness of 600 μm or more. From these results, it can be seen that in the case of the relatively small-sized envelope 90, the above-described absorbing effect can be sufficiently obtained even if such a solder material is used as the joining member. In the case of the large-sized envelope 90, if Sn / Ag-based solder material is used as the joining member 206, the thickness of the envelope itself increases and the panel becomes large. It is more desirable to use a joining member containing In as a main component, which has a high (elasticity) and a low melting point.

Since the joining member 206 made of In or the like behaves as an elastic body, residual stress is likely to occur inside the joining member due to the difference in shrinkage amount between the plates made of different glass materials. Therefore, when the envelope 90 becomes large, although the crack does not occur, the residual stress causes the plate to warp. In order to prevent this, it is necessary to further increase the thickness of the substrate glass, resulting in an increase in the size of the panel. The warp of the plate due to such residual stress can be eliminated by using, as the joining member 206, a material having large plasticity that absorbs a difference in shrinkage amount between the plates by causing permanent strain.

Next, the configuration and formation process of each component of the panel of this embodiment will be described in detail.

<Electron Emitting Element> Here, as the electron emitting element provided on the electron source substrate 80 of the rear plate 81, an M.M. The element structure of Hartwell will be described. FIG. 4A shows the M. Top view of Hartwell device configuration,
(B) is the sectional view.

Referring to FIG. 4, in this SCE element, a pair of element electrodes 2 and 3 having an element electrode interval L and an element electrode length W are formed on a substrate 1 made of glass or the like. The conductive thin film 4 is formed so as to straddle the structure, and the electron emitting portion 5 is formed near the center of the conductive thin film 4.

The size and thickness of the substrate 1 should be determined in consideration of the number and size of the electron-emitting devices installed on the substrate, and the mechanical strength of the atmospheric pressure resistant structure when forming the envelope. Is set appropriately. As the material of the glass of the substrate 1, it is general to use a soda lime glass, but a substrate having a 0.5 μm thick silicon oxide film formed by a sputtering method on the substrate as a sodium block layer is used. In some cases. In addition to this, the substrate 1 can also be manufactured using a glass having a small amount of alkali ions such as sodium or a quartz substrate. In this embodiment, non-alkali glass is used.

FIG. 5 shows the comparison result of the performance of the electron-emitting device between the non-alkali glass and other glass materials. In FIG.
"○" (white circle) is the performance when non-alkali glass is used, and "●" (black circle) is electric glass for plasma display suitable as a material for the face play 82 (for example, PD-200 with a low alkali content (Asahi Glass Co., Ltd.). ) Company)))
The performance when using quartz glass, and the square (□) shows the performance when using quartz glass. The vertical axis represents the electron emission efficiency (%), and the horizontal axis represents the life (hour). The balance between the lifetime and the electron emission efficiency changes depending on the driving conditions of the electron emitting element. Quartz glass is not practical because it has a high melting point, is difficult to process, and is extremely expensive. The performance of alkali-free glass is higher than that of other materials. Although not shown in FIG. 5, the substrate in which the sodium block layer is provided on the soda-lime glass has almost the same performance as that of the PDP glass.

As a material for the device electrodes 2 and 3, a general conductor material is used. For example, Ni, Cr, Au, M
Metals such as o, Pt and Ti and metals such as Pd-Ag are suitable. Further, a printed conductor made of metal oxide and glass, a transparent conductor such as ITO, or the like can be used.
In either case, the film thickness of the device electrode is preferably several tens n.
The range from m to several μm is suitable.

The element electrode interval L, the element electrode length W, the element electrode shape, etc. are designed as appropriate according to the form in which the actual element is applied, but the element electrode interval L is preferably several thousand Å. ˜1 mm, and more preferably in the range of 1 μm to 100 μm in consideration of the voltage applied between the device electrodes. The device electrode length W is preferably in the range of several μm to several hundreds of μm in consideration of the resistance value of the electrode and the electron emission characteristics.

A commercially available paste containing metal particles such as platinum Pt can be applied and formed on the device electrodes 2 and 3 by a printing method such as offset printing. Further, in order to obtain a more precise pattern, a photosensitive paste containing platinum Pt or the like is applied by a printing method such as screen printing,
It can also be formed by a process of exposing and developing using a photomask.

As the conductive thin film 4, a fine particle film composed of fine particles is particularly preferable in order to obtain good electron emission characteristics. The film thickness of the conductive thin film 4 is appropriately set in consideration of the step coverage to the device electrodes 2 and 3, the resistance value between the device electrodes, and the forming processing conditions described later, but preferably several Å to several thousand. Å, more preferably 1
It is good to set it in the range of 0Å to 500Å. According to the study by the applicants, palladium Pd is generally suitable as the conductive film material of the conductive thin film 4, but the material is not limited to this. As a method for forming the conductive thin film 4, a sputtering method, a method of baking after applying a solution, or the like is appropriately used.

The electron-emitting portion 5 can be formed by performing an energization process called forming after the conductive thin film 4 is formed. For example, after applying an organic palladium solution, it is fired to form a palladium oxide PdO film to form a conductive thin film 4, and thereafter, electricity is heated in a reducing atmosphere in which hydrogen coexists to form a palladium Pd film, which is simultaneously cracked. The electron emitting portion 5 is formed by forming the portion.

In the SCE element constructed as described above,
By applying a predetermined voltage between the pair of device electrodes 2 and 3 and applying a current (emission current) to the surface of the conductive thin film 4 (device surface), electrons are emitted from the vicinity of the crack in the electron emission portion 5. .
In the example shown in FIG. 4, the electron emitting portion 5 is shown as a rectangular shape in the center of the conductive thin film 4, but this is a schematic illustration and the actual position of the electron emitting portion is shown. It does not faithfully represent the shape or shape.

<Electron Source Substrate Forming Process> FIGS. 6 to 10
FIG. 6 is a process explanatory view showing an example of a process of forming an electron source substrate including the SCE element as described above. Below, FIG.
The process of forming the electron source substrate will be described with reference to FIGS.

[Glass Substrate / Device Electrode Formation] As shown in FIG. 6, device electrodes 22 and 23 are formed on a glass substrate 21 by a sputtering method. Here, first, a titanium Ti film having a film thickness of 5 nm is formed as an undercoat layer, a platinum Pt film having a film thickness of 40 nm is further formed on the titanium Ti film, and then a photoresist is applied, followed by a series of exposure, development and etching. The device electrodes 22 and 23 were patterned by the photolithography method. The device electrodes 22 and 23 have a distance L of 10 μm and a corresponding length W of 100 μm.

[Formation of Y-direction wiring (lower wiring)] Element electrode 2
When the layers 2 and 23 are formed, subsequently, as shown in FIG.
A Y-direction wiring (lower wiring) 24 as a common wiring is formed in a linear pattern so as to connect one element electrode 23 in the column direction. Here, the material was screen-printed with silver Ag photopaste ink, dried, and then exposed and developed in a predetermined pattern. After development 480
The Y-direction wiring 24 was formed by firing at a temperature of around ℃. Y
The thickness of the directional wiring 24 was about 10 μm and the width was 50 μm. The end portion of the Y-direction wiring 24 has a larger line width in order to be used as a wiring extraction electrode.

[Interlayer Insulation Layer Formation] When the Y-direction wiring 24 is formed, subsequently, as shown in FIG. 8, an interlayer for insulating an X-direction wiring (upper wiring) 26 and a Y-direction wiring 24, which will be described later, from each other. The insulating layer 25 is formed so as to intersect the Y-direction wiring 24. The interlayer insulating layer 25 is formed so as to cover the intersection of the Y-direction wiring 24 and the X-direction wiring 26, and the interlayer insulating layer 25 electrically connects the X-direction wiring 26 and the other element electrode 22. A contact hole 28 is formed in the connection portion so that the connection can be made. Here, first, a photosensitive glass paste containing PbO as a main component was screen-printed, and then exposed and developed. Repeat this 4 times, and finally 4
The interlayer insulating layer 25 was formed by firing at a temperature of around 80 ° C. The interlayer insulating layer 25 had a total thickness of about 30 μm and a width of 150 μm.

[X Direction Wiring (Upper Wiring) Formation] When the interlayer insulating layer 25 is formed, subsequently, as shown in FIG. 9, the X direction wiring (upper wiring) 26 intersects with the Y direction wiring 24. It is formed on the interlayer insulating layer 25. Here, the interlayer insulating layer 2
The step of screen-printing the Ag paste ink on No. 5 and then drying was repeated twice (twice coating), and then baked at a temperature of about 480 ° C. to form the X-direction wiring 26. The X-direction wiring 26 thus formed is electrically connected to the device electrode 22 via the contact hole 28 formed in the interlayer insulating layer 25. That is, the X-direction wiring 26 connects the element electrodes 22 in the row direction and functions as a scanning electrode after being formed into a panel. The thickness of the X-direction wiring 26 is about 15 μm. Although not shown, the lead-out terminal to the external drive circuit was also formed by the same method.

Through the above steps, the substrate having the XY matrix wiring is formed. It is desired that the X-direction wiring 26 and the Y-direction wiring 24 have low resistance so that a substantially uniform voltage can be supplied to a large number of surface conduction elements, and materials, film thickness, wiring width, etc. are appropriately set. It

[Formation of Element Film] After the XY matrix wiring is formed, subsequently, as shown in FIG.
The surface conduction electron-emitting device film 27 is formed so as to straddle 2 and 23. Here, first, the substrate 21 was thoroughly cleaned, and then the surface was treated with a solution containing a water repellent so that the surface became hydrophobic. The purpose of this is to allow the aqueous solution for forming the element film, which is applied thereafter, to be formed on the element electrode with a proper spread. Specifically, DDS (dimethyldiethoxysilane) as a water repellent
The solution was sprayed onto the substrate 21 and dried with warm air at 120 ° C. After that, an element film 27 was formed between the element electrodes 22 and 23 by an inkjet coating method.

11A and 11B schematically show the process of forming the element film. In this example, in order to obtain a palladium film as an element film, first, a palladium-proline complex (0.15% by weight) is dissolved in an aqueous solution in which water and isopropyl alcohol (IPA) are mixed at a ratio of 85:15, An organic palladium-containing solution was obtained. Besides this, some additives were added. A droplet applying device 2 including a droplet of this solution is formed of an inkjet ejecting device using a piezo element, for example.
In No. 9, the dot diameter was adjusted to 60 μm and applied between the device electrodes 22 and 23 (see FIG. 11B). Then, the substrate 21 was heated and baked in air at 350 ° C. for 10 minutes to obtain palladium oxide (PdO).
A film having a dot diameter of about 60 μm and a maximum thickness of 10 nm was obtained. The planarity and uniformity of the palladium oxide film thus obtained have a great influence on the device characteristics.

In the actual device film forming process, in order to compensate for the planar variation of the individual device electrodes on the substrate 21, pattern displacements are observed at several points on the substrate 21, and the observation points are observed. The deviation amount of the points is linearly approximated and the position is complemented, and then the element film shape is formed. This makes it possible to eliminate the positional deviation of all the pixels and form the element film accurately at the corresponding positions.

Through the above steps, the palladium oxide PdO film (conductive thin film) was formed on the element portion.

[Reduction Forming] Next, in this step called forming, the conductive thin film is energized to cause cracks therein to form the electron emitting portion 27a. 11C and 11D schematically show this reduction forming process.

In this reduction forming, specifically,
A hood-like lid is covered so as to cover the entire substrate, leaving a take-out electrode portion around the substrate 21, to create a vacuum space inside the substrate, and an external power source connects the electrode terminal portion to the Y-direction wiring 24. A voltage is applied between the X-direction wirings 26 to energize between the device electrodes 22 and 23 (see FIG. 11C).
By this energization treatment, the conductive thin film is locally destroyed, deformed, or altered to form the electron emitting portion 27a having a high electrical resistance (see FIG. 11D).

When the above energization is carried out by energizing and heating in a vacuum atmosphere containing a slight amount of hydrogen gas, the reduction is promoted by hydrogen and the palladium oxide PdO is changed into a palladium Pd film. At the time of this change, due to the reduction and contraction of the film, a crack is partially generated and the electron emitting portion 27a is formed. The crack generation position and its shape are greatly affected by the uniformity of the original film. In order to suppress the characteristic variations of a large number of elements, it is more preferable that the cracks occur in the central portion and be as linear as possible.

Electrons are emitted from the vicinity of the crack formed by the above-mentioned forming under a predetermined voltage, but under the current conditions, the generation efficiency is still very low. The resistance value of the obtained conductive thin film is 1
The value was from 0 ² to 10 ⁷ Ω.

Here, the voltage waveform used in the forming process will be briefly introduced.

FIG. 12 shows an example of the voltage waveform used in the forming process. When performing the forming process using the applied voltage of the pulse waveform, as shown in FIG. 12A, the case where the pulse whose pulse peak value is a constant voltage is applied,
There is a case where the pulse peak value is applied while being increased as shown in (b).

In FIG. 12A, T1 is the pulse width of the voltage waveform, and T2 is the pulse interval. In this example, the pulse width T
1 is 1 μsec to 10 msec, and the pulse interval T2 is 10
The peak value of the triangular wave (peak voltage during forming) is appropriately selected as μsec to 100 msec.

In the example of FIG. 12B, the pulse width T1 and the pulse interval T2 are the same as those in the example of FIG. 15A, but the peak value of the triangular wave (peak voltage during forming) is For example, it is designed to be increased by about 0.1 V step.

To end the forming process, a device current is measured by inserting a voltage that does not locally break or deform the conductive film between the forming pulses, for example, a pulse voltage of about 0.1 V, and measure the device current. Obtain the resistance value from the measurement result,
The time when the obtained resistance value was, for example, 1000 times or more the resistance before the forming treatment was shown.

[Activation-Carbon deposition] As described above, in the state where the forming treatment is simply performed,
The electron generation efficiency is very low. Therefore,
In order to increase the electron emission efficiency, it is desirable to perform a process called activation on the above device. In this process, a hood-like lid is covered to create an internal vacuum space between the substrate and the XY wiring (24 , 26)
The pulse voltage is repeatedly applied to the device electrodes 22 and 23 through. Then, a gas containing carbon atoms is introduced, and carbon or a carbon compound derived from the gas is deposited as a carbon film in the vicinity of the crack described above.

[0073] In the activation step, a trinitrile such as carbon source, was introduced into vacuum space through a slow leak valve was maintained 1.3 × 10- ⁴ Pa. The pressure of the trinitrile to be introduced is slightly affected by the shape of the vacuum device and the members used in the vacuum device.
About 10- ⁵ Pa~1 × 10- ² Pa is suitable.

13 (a) and 13 (b) show a preferred example of voltage application used in the activation step. The maximum voltage value to be applied is appropriately selected within the range of 10 to 20V. FIG.
In (a), T1 is the positive and negative pulse width of the voltage waveform,
T2 is a pulse interval, and the voltage values are set to have equal positive and negative absolute values. In FIG. 13B, T1, T
1'is a positive pulse width and a negative pulse width of the voltage waveform, T2 is a pulse interval, and T1> T1 ', and the voltage values are set to have equal positive and negative absolute values. Here, the voltage applied to the element electrode 23 is positive, and the element current If flows from the element electrode 23 to the element electrode 22 in a positive direction. After about 60 minutes, when the emission current Ie reached almost saturation, the energization was stopped, the slow leak valve was closed, and the activation treatment was completed.

Through the above steps, an electron source substrate having an electron source element could be manufactured.

For reference, a part of the prior art by the applicant of the present invention will be introduced below regarding the technology relating to the SCE element.

Regarding the production of the SCE element by the ink jet forming method, JP-A-09-102271 and JP-A-2000-
This is described in detail in Japanese Patent No. 251665. Further, examples of arranging SCE elements in a matrix are described in detail in JP-A-64-031332 and JP-A-07-326311. Further, a wiring forming method of an electron source substrate having an SCE element is described in JP-A-08-185818 and JP-A-09-050757, and a driving method thereof is JP-A-06-342.
It is described in detail in 636 Public Relations. Further, it is possible to dispose a resistance element in series with an SCE element for the purpose of improving the uniformity of electron emission element characteristics.
It is disclosed in Japanese Patent No. 247937 and Japanese Patent Laid-Open No. 07-326283.

<Substrate Characteristics> The basic characteristics of the electron-emitting device of the electron source substrate manufactured by the above-described manufacturing procedure will be described.

FIG. 14 is a schematic diagram of a measurement / evaluation apparatus for measuring the electron emission characteristics of the SCE element on the electron source substrate described above. The SCE element to be evaluated has the element electrodes 22 and 23 formed on the substrate 21.
The element film 27 is formed so as to straddle 23, and the electron emitting portion 27 a is formed near the center of the element film 27. In FIG. 14, 51 is a device voltage V for the electron-emitting device.
f is a power source for applying f, 50 is an ammeter for measuring the device current If flowing through the device film 27 including the electron emitting part 27a between the device electrodes 22 and 23, and 54 is emitted from the electron emitting part 27a of the device. Is an anode electrode for capturing the emission current Ie, 53 is a high-voltage power supply for applying a voltage to the anode electrode 54, and 52 is an ammeter for measuring the emission current Ie emitted from the electron emission portion 27a of the device. is there.

The electron-emitting device and the anode electrode 54 are installed in a vacuum device 55, and the vacuum device 55 is equipped with an exhaust pump 56, vacuum gauge, and other equipment necessary for the vacuum device, and under a desired vacuum. The electron emission device can be measured and evaluated. The anode electrode 54 is arranged above the electron-emitting device, and has a power source 53 and an ammeter 52.
Are connected. When measuring the device current If flowing between the device electrodes of the electron-emitting device and the emission current Ie to the anode, the power supply 51 and the ammeter 5 are connected to the device electrodes 22 and 23.
Connect to 0. The voltage of the anode electrode 54 is 1k.
V to 10 kV, and the distance H between the anode electrode 54 and the electron-emitting device was in the range of 2 mm to 8 mm.

FIG. 15 is a characteristic diagram showing a typical example of the relation between the emission current Ie of the electron-emitting device and the device current If and the device voltage Vf measured by the measurement / evaluation apparatus shown in FIG. Although the emission current Ie and the device current If are significantly different in magnitude, in the example of FIG. 15, the vertical axis is expressed in arbitrary units on a linear scale for qualitative comparative examination of changes in If and Ie. As can be seen from this measurement result, the emission current Ie at a voltage of 12 V applied between the device electrodes was measured, and as a result, the average was 0.6 μA and the electron emission efficiency was 0.
15% was obtained. Further, the uniformity between the elements was good, and the variation of Ie among the elements was 5%, which was a good value.

The above electron-emitting device has the following three characteristics with respect to the emission current Ie. (1) As is clear from the measurement results of FIG. 15, the electron-emitting device has a certain voltage (called a threshold voltage. V in FIG. 15).
th. ) When the device voltage above is applied, the emission current I rapidly increases.
e increases, while the emission current Ie is hardly detected below the threshold voltage Vth. That is, the emission current Ie
It can be seen that the characteristics as a non-linear element having a clear threshold voltage Vth are shown. (2) Since the emission current Ie depends on the element voltage Vf, the emission current Ie can be controlled by the element voltage Vf. (3) The emitted charges captured by the anode electrode 54 depend on the time for which the device voltage Vf is applied. That is, the amount of charge captured by the anode electrode 54 can be controlled by the time for which the device voltage Vf is applied.

<Sealing-Panelization> The panel enclosure 90 shown in FIG. 1 is constituted by the rear plate made of the electron source substrate having the simple matrix arrangement as described above, the face plate, and the supporting frame. Since the sealing of the envelope 90 is as described above, the description thereof will be omitted here.

FIGS. 16A and 16B are schematic views of the fluorescent film provided on the face plate of the image display device shown in FIG. In the case of monochrome, the fluorescent film 84 is composed of only the phosphor, but in the case of a color fluorescent film, it is composed of a black conductor 91 and a phosphor 92 called a black stripe or a black matrix depending on the arrangement of the phosphors. . The purpose of providing the black stripes and the black matrix is to make the color mixture or the like inconspicuous by making the portions of the three primary color phosphors, which are required for color display, between the respective phosphors 92 black, and to make the phosphor film 84 inconspicuous. This is to suppress a decrease in contrast due to reflection of external light. In the example of FIG. 16A, the black conductor 91 has a structure in which substantially square openings are provided in a matrix.
A phosphor 92 is formed in each opening. On the other hand, FIG.
In the example of 6 (b), the shape of the opening of the black conductor 91 in which the phosphor 92 is formed is elliptical.

As shown in FIG. 1, a metal back 85 is usually provided on the inner surface side of the fluorescent film 84. The purpose of providing the metal back 85 is to improve the brightness by specularly reflecting the light toward the inner surface side of the light emission of the phosphor toward the face plate 82 side, and to act as an anode electrode for applying an electron beam acceleration voltage. And so on. Such a metal back 85 can be produced by performing a smoothing process (usually called filming) on the inner surface of the fluorescent film after producing the fluorescent film, and then depositing A1 by vacuum evaporation or the like.

On the face plate 82, PDH glass used for plasma display, specifically, PD-200 (made by Asahi Glass Co., Ltd.) with a low alkali content is used.
Materials are used. With this glass material, the coloring phenomenon of glass does not occur, and if the plate thickness is about 3 mm,
Even when driven at an acceleration voltage of 10 kV or higher, there are advantages such as a sufficient shielding effect for suppressing the leakage of secondary soft X-rays. The rear plate 81 is made of non-alkali glass having excellent characteristics (electron emission efficiency and durability) of the electron-emitting device.

When the envelope 90 is sealed, in the case of color, it is necessary to make the phosphors of the respective colors correspond to the electron-emitting devices. Therefore, it is necessary to perform a sufficient alignment by the abutting method of the upper and lower substrates. There is.

The degree of vacuum at the time of sealing is required to be about 10 ^-5 Pa, and in some cases, a getter process is performed in order to maintain the degree of vacuum after sealing the envelope. In the getter process, for example, immediately before or after sealing the envelope, a getter arranged at a predetermined position (not shown) in the envelope is heated by a heating method such as resistance heating or high frequency heating. Then, a process of forming a vapor deposition film is performed.
In this case, the getter usually has Ba as a main component, and due to the adsorption action of the vapor deposition film, for example, 10 ^-3 to 10 ^-5 Pa is obtained.
It is possible to maintain the degree of vacuum.

<Image Display Element> According to the basic characteristics of the SCE element according to the present invention described above, the electrons emitted from the electron emission portion are the pulse voltage applied between the opposing element electrodes at the threshold voltage or higher. Is controlled by the crest value and the width, and the current amount is also controlled by the intermediate value thereof, which enables halftone display. In the case where a large number of electron-emitting devices are arranged, the selection line is determined by the scanning line signal of each line, and the pulsed voltage is appropriately applied to each device through each information signal line, so that any device can be used appropriately. It is possible to apply a voltage and turn on each element
can do. As a method of modulating the electron-emitting device according to an input signal having a halftone, there are a voltage modulation method and a pulse width modulation method.

The outline of the driving device will be described below.

FIG. 17 is a block diagram showing a schematic structure of an image display device for television display based on an NTSC television signal, which is an embodiment of the display device of the present invention.

In FIG. 17, 101 is a display panel constructed by using electron sources arranged in a simple matrix, 102 is a scanning circuit, 103 is a control circuit, 104 is a shift register,
105 is a line memory, 106 is a sync signal separation circuit, 1
Reference numeral 07 is an information signal generator, and Va is a DC high voltage power supply.

A scan circuit 102 having a scan driver (driving circuit) for applying a scan line signal is connected to the X-direction wiring of the display panel 101 using electron-emitting devices, and data for applying an information signal is applied to the Y-direction wiring. An information signal generator 107 having a driver (driving circuit) is connected. In the case of implementing the voltage modulation method, as the information signal generator 107, a circuit that generates a voltage pulse of a fixed length but appropriately modulates the peak value of the pulse according to the input data is used. When the pulse width modulation method is implemented, the information signal generator 107 generates a voltage pulse having a constant crest value, but appropriately modulates the width of the voltage pulse according to the input data. Use a circuit.

The control circuit 103 includes the sync signal separation circuit 10
Based on the synchronization signal Tsync sent from the control unit 6, the control signals Tscan, Tsft, and Tmry are sent to each unit. The sync signal separation circuit 106 receives N externally input.
It is a circuit for separating a sync signal component and a luminance signal component from a TSC television signal. This luminance signal component is input to the shift register 104 in synchronization with the synchronization signal.

The shift register 104 includes the control circuit 103.
The operation is controlled based on the shift clock sent from the device, and the luminance signal serially input in time series is serial / parallel converted for each line of the image.
This serial / parallel converted image data for one line (corresponding to drive data for n electron-emitting devices) is
It is output from the shift register 104 as n parallel signals.

The line memory 105 is a storage device for storing data for one line of an image for a required time, and the stored contents are input to the information signal generator 107. The information signal generator 107 is a signal source for appropriately driving each of the electron-emitting devices according to each luminance signal, and its output signal is output through the Y-direction wiring to the display panel 1.
01, and is applied to each electron-emitting device at the intersection with the scanning line being selected by the X-direction wiring. By sequentially scanning the X-direction wiring, it becomes possible to drive the electron-emitting devices on the entire surface of the panel.

In the present image display device having the panel shown in FIG. 1 as described above, each electron-emitting device is provided with
Electrons are emitted by applying a voltage through the XY wirings in the panel, and a high voltage is applied to the metal back 85, which is an anode electrode, through the high voltage terminal Hv to accelerate the electrons emitted from each electron emitting element, thereby causing fluorescence. The image can be displayed by striking the membrane.

The configuration of the image forming apparatus described here is an example of the image forming apparatus of the present invention, and various modifications can be made based on the technical idea of the present invention. Although the NTSC system is mentioned as the input signal, the input signal is not limited to this, and PAL, HDTV, or the like may be used.

(Second Embodiment) FIG. 18 is an enlarged sectional view of part of a display panel according to a second embodiment of the present invention.
The panel of this embodiment has substantially the same configuration as that of the panel of the first embodiment (see FIG. 1) described above, except that the defining member 205 is not provided. In FIG.
The same components as those shown in FIG. 1 are designated by the same reference numerals.

FIG. 19 is a view for explaining a method of sealing the panel shown in FIG. First, in a state where the face plate 82 and the rear plate 81 are held at a predetermined gap, heating is performed to a temperature (about 180 ° C.) at which the joining member 206 made of In melts. And the joining member 20
6 is melted, the face plate 82 is moved and brought close to by the positioning device 200 until the joining member 206 has a thickness of 300 μm, and in this state, the face plate 82 and the rear plate 81 are gradually cooled to surround the enclosure. The container 90 is formed. If these processes are performed in a vacuum environment, the gas released from the member during heating is not confined in the envelope 90, and it is possible to form a vacuum box in a high vacuum state after cooling.

According to the above sealing method, the height defining member 2
It is possible to easily set the thickness of the joining member 206 without providing 05. If the envelope 90 has a size of about 100 mm × 100 mm, a sufficient atmospheric pressure resistant structure can be obtained without using spacers if the glass plate thickness of the face plate 82 and the rear plate 81 is set to 2 mm or more. In the structure without the spacer, the panel of the present embodiment, which can easily define the height, is particularly effective.

In each of the embodiments described above, the SCE element is taken as an example of the electron-emitting device provided on the electron source substrate, but the present invention is not limited to this, and other electron-emitting devices, For example, a field emission device may be used.

Although the joining member is provided between the support frame and the face plate, the present invention is not limited to this. For example, the structure may be such that the rear plate and the support frame are joined by a joining member. In this case, the support frame and the face plate are bonded with frit glass. Further, a structure may be adopted in which both the support frame and the face plate and the rear plate and the support frame are joined by a joining member.

Further, although the envelope is formed by joining the face plate and the rear plate to the support frame, the present invention is not limited to this. The sealing structure of the display panel of the present invention can be applied to a panel structure having no support frame, for example. In this case, a face plate and a rear plate are joined by a joining member to form a panel structure, and a height regulating member is provided to hold the face plate and the rear plate at a predetermined interval.

[0105]

As described above, according to the present invention,
Since different kinds of glass materials can be used for the rear plate and the face plate, for example, a material having a good electron-emitting device performance is used for the rear plate, the face plate has high electric resistance, and coloring by electron beams or X-rays is used. Can be used. Therefore, it is possible to provide an image display device having excellent electron emission device characteristics and less deterioration in transmittance (coloring phenomenon) due to irradiation with an electron beam or the like, which is excellent in stability and display quality, as compared with a conventional one. it can.

Further, according to the present invention, since a material having an excellent X-ray shielding effect can be used for the face plate, the thickness of the face plate can be made thinner than the conventional one, and the image is light and inexpensive. A display device can be provided.

[Brief description of drawings]

FIG. 1 is a view for explaining a panel structure of a display device according to a first embodiment of the present invention, (a) is a perspective view in which a part of the panel is cut away, and (b) is shown in (a). Broken line part a of the panel
FIG.

FIG. 2 is a diagram showing a schematic composition and a coefficient of thermal expansion of a typical substrate glass used as a material of a device in the fields of optoelectronics.

FIG. 3 is a diagram showing performance results of an envelope when In is used as a joining member of the display panel shown in FIG.

FIG. 4 (a) shows M. FIG. 3B is a top view of the Hartwell device configuration, and FIG.

FIG. 5 is a diagram showing a comparison result of performances of electron-emitting devices of non-alkali glass and other glass materials.

6A to 6C are process explanatory diagrams for explaining a process of forming an electron source substrate including the SCE element shown in FIG.

7A to 7C are process explanatory views for explaining a process of forming an electron source substrate including the SCE element shown in FIG.

8A to 8C are process explanatory views for explaining a process of forming an electron source substrate including the SCE element shown in FIG.

9A and 9B are process explanatory diagrams for explaining a process of forming an electron source substrate including the SCE element shown in FIG.

FIG. 10 is a process explanatory view for explaining the formation process of the electron source substrate including the SCE element shown in FIG.

11A to 11D are views for explaining a series of processes from element film formation to forming of the electron source substrate of the present invention.

12A and 12B are waveform charts showing an example of an applied voltage waveform at the time of forming processing of the electron source substrate of the present invention.

13A and 13B are diagrams showing a preferred example of voltage application used in the activation step.

FIG. 14 is a schematic diagram of a measurement / evaluation apparatus for measuring the electron emission characteristics of the SCE element of the electron source substrate used in the display panel of the present invention.

15 is a characteristic diagram showing a typical example of the relationship between the emission current Ie, the device current If, and the device voltage Vf measured by the measurement / evaluation apparatus shown in FIG.

16 (a) and 16 (b) are schematic diagrams of a fluorescent film provided on a face plate of the display panel shown in FIG.

FIG. 17 is an embodiment of an image display device of the present invention,
It is a block diagram showing a schematic structure of an image display device for television display based on an NTSC television signal.

FIG. 18 is an enlarged cross-sectional view of a part of the display panel according to the second embodiment of the present invention.

19 is a diagram for explaining a method of sealing the display panel shown in FIG.

FIG. 20 is a schematic view of a conventional display panel using an electron source substrate in which SCE elements are arranged in a matrix.

[Explanation of symbols]

1 substrate 2, 3, 22, 23 Element electrodes 4 Conductive thin film 5, 27a Electron emission part 21,80 Electron source substrate 24, 88 X-direction wiring 25 Interlayer insulation layer 26, 89 Y direction wiring 27 Surface conduction electron-emitting device film 28 contact holes 29 Droplet application device 50, 52 ammeter 51 power supply 53 High-voltage power supply 54 Anode electrode 55 Vacuum device 56 Exhaust pump 81 Rear plate 82 face plate 83 glass substrate 84 Fluorescent film 85 metal back 86 Support frame 87 Electron-emitting device 90 envelope 91 black conductor 92 phosphor 101 display panel 102 scanning circuit 103 control circuit 104 shift register 105 line memory 106 Motivation signal separation circuit 107 information signal generator 200 Positioning device 203 frit glass 204 Undercoat layer 205 Height regulating member 206 Joining member Hv high voltage terminal

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Koji Ueda             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F-term (reference) 4G061 AA02 AA03 AA06 AA09 BA03                       BA11 CA02 CB02 CB14 CD02                       CD22 CD25 DA24 DA35                 5C012 AA01 BC03                 5C032 AA01 BB18                 5C036 EE17 EF01 EF06 EF08 EG02                       EG05

Claims (16)

[Claims] 1. A display panel in which a vacuum envelope is formed by joining first and second plates facing each other, and a joining member having a melting point and elasticity at a predetermined temperature. A display panel in which the first and second plates are joined together by. 2. The display panel according to claim 1, wherein the first plate and the second plate are made of materials having different thermal expansion coefficients. 3. The display panel according to claim 1, wherein an undercoat layer is formed on a surface to be joined by the joining member so as to enhance adhesion with the joining member. 4. A support frame having a first plate joined to one end surface thereof and a second plate joined to the other end surface thereof, wherein one of the first plate and the support frame is provided. 2. The display according to claim 1, wherein at least one of the end faces on the side of or the second plate and the end face on the other side of the support frame is joined by a joining member. panel. 5. One end is joined to the first plate, and the second plate
2. The display panel according to claim 1, further comprising a height defining member, the other end of which is abutted against the plate, for holding the joining member with a predetermined thickness. 6. The display panel according to claim 5, wherein the height defining member is provided inside or outside the vacuum envelope. 7. A plurality of spacers for holding the first and second plates at a predetermined interval, and at least one of the plurality of spacers is constituted by a height defining member. The display panel according to item 5. 8. The display panel according to claim 5, wherein the height defining member is provided adjacent to a portion joined by the joining member. 9. The display panel according to claim 1, wherein the thickness of the joining member is in the range of 0.01 to 1% of the maximum length of the portion joined by the joining member. 10. The display panel according to claim 1, wherein the joining member is made of a metal or an alloy. 11. The display panel according to claim 10, wherein the bonding member is made of a material containing In as a main component. 12. The first plate is a rear plate in which a plurality of electron-emitting devices are arranged in a matrix, and the second plate is a plurality of plates to which electrons emitted from the plurality of electron-emitting devices are respectively irradiated. A face plate having a phosphor formed thereon.
The display panel according to any one of 1. 13. A method of sealing a display panel, wherein first and second plates arranged to face each other are bonded to each other to form a vacuum envelope, wherein a bonding portion of the first and second plates is bonded. A method for sealing a display panel, comprising: providing a joining member having a melting point and elasticity at a predetermined temperature, and melting the joining member to join the joined portion. 14. A first plate and a second plate which are arranged to face each other, and the first plate is joined to an end face on one side, and the second plate is joined to an end face on the other side. In a method for sealing a display panel in which a vacuum envelope is formed by a support frame, after joining the second plate and the end face on the other side of the support frame, the first plate and the support frame are joined together. A display panel, characterized in that a joining member having a melting point at a predetermined temperature and having elasticity is provided at a joining portion with the end face on one side, and the joining member is fused to join the joining portion. Sealing method. 15. The display panel according to claim 13 or 14, wherein an undercoat layer for enhancing the adhesion with the joining member is formed in advance on the surface joined by the joining member. Sealing method. 16. An image display device, comprising: the display panel according to claim 1; and a drive circuit that supplies a drive voltage to the display panel to display an image. .