JP2008243775A - Image display apparatus, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image display apparatus equipped with a joint resistant to heat of 300°C or more in bonding glass substrates having low coefficient of thermal expansion, and to provide its manufacturing method. <P>SOLUTION: The image display apparatus comprises an envelope which has a back substrate 11 and a front substrate 12 placed oppositely to the back substrate 11 and a plurality of display elements connected to wiring formed in matrix. Cracks caused by thermal stress due to difference of coefficients of thermal expansion can be avoided and a joint having resistance to temperature of 300°C or more can be formed by preparing wall members 13 and 14 made of metal or inorganic material having linear expansion coefficient of 80 to 90 (×10<SP>-7</SP>/K) and melting point of 500°C or more between the back substrate 11 and the front substrate 12, Cu layers 21 and 22 having thickness of 10 to 200 μm on the metal or inorganic material, and bonding both substrates with metallic tin or tin alloy containing 50% or less of Sn in mass ratio. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to an image display device having a substrate disposed oppositely and a plurality of display elements provided between the substrates, and a manufacturing method for manufacturing the image display device.

  In recent years, as a next-generation lightweight and thin flat display device, a display device in which a large number of electron-emitting devices are arranged and opposed to a phosphor screen has been developed. As the electron-emitting device, a field emission type device or a surface conduction type device is assumed. Usually, a display device using a field emission type electron-emitting device as an electron-emitting device is a field emission display (hereinafter referred to as FED), and a display device using a surface conduction type electron-emitting device as an electron-emitting device is a surface device. It is called a conduction electron emission display (hereinafter referred to as SED).

  The FED has a front substrate and a rear substrate that are arranged to face each other with a predetermined gap, and these substrates are connected to each other through a rectangular frame-shaped side wall to form a vacuum envelope. It is composed. A phosphor screen is formed on the inner surface of the front substrate, and a large number of electron-emitting devices are provided on the inner surface of the rear substrate as electron emission sources that excite the phosphor to emit light. Further, in order to support an atmospheric pressure load applied to the back substrate and the front substrate, a plurality of support members are disposed between these substrates.

  The potential on the back substrate side is approximately 0 V, and the anode voltage Va is applied to the phosphor screen. The red, green, and blue phosphors that make up the phosphor screen are irradiated with the electron beams emitted from the electron-emitting devices, and the phosphors emit light to display an image. Further, since a high voltage is applied to the phosphor screen, high strain point glass is used for the front substrate, the rear substrate, the side walls, and the plate glass for the support member. In such an FED, the gap between the front substrate and the rear substrate can be set to several millimeters or less, which is lighter than a cathode ray tube (CRT) currently used as a display for televisions and computers. Thinning can be achieved.

In this display device, it is known that a bonding material such as In is used as a bonding material for sealing between the entire substrate and the back substrate (see Patent Document 1 and Patent Document 2).
By the way, the above-mentioned display device excites the phosphor by the electron beam to emit light, so that the temperature of the display device rises and it is necessary to maintain a vacuum at the joint portion. In the joining using, anxiety remains in its reliability.
For bonding with high reliability, it is necessary to use a bonding material having a melting point of 300 ° C. or higher, and the use of Pb, Cd, or the like, which is generally known as a high melting point bonding material, has been studied. Since these materials may affect environmental problems due to their toxicity, realization of a high melting point bonding material is demanded instead.
JP2002-182585 JP 2004-014460 A

The present invention provides an image display device including a bonding portion having a heat resistance of 300 ° C. or higher and a manufacturing method thereof without affecting environmental problems in bonding between glass substrates having a low coefficient of thermal expansion. It is aimed.

The first aspect of the present invention is connected to an envelope having a rear substrate, a front substrate opposed to and bonded to the rear substrate, and wiring formed in a matrix and provided in the envelope. In the image display device including a plurality of display elements, the joint portion between the back substrate and the front substrate has a linear expansion coefficient of 80 to 90 (× 10 ⁻⁷ / K) formed on the back substrate surface. A first side wall member made of a metal material or an inorganic material having a melting point of 500 ° C. or higher, a first Cu layer having a thickness of 10 to 200 μm formed on the surface of the first side wall member, An Sn-containing high melting point bonding layer formed on the surface of the first Cu layer and having a thickness of 10 to 100 μm, and a second Cu having a thickness of 10 to 200 μm formed on the surface of the Sn-containing high melting point bonding layer Layer, the surface of the second Cu layer and the front And a second side wall member made of a metal material or an inorganic material having a linear expansion coefficient of 80 to 90 (× 10 ⁻⁷ / K) and a melting point of 500 ° C. or higher. An image display device.

In the first aspect of the present invention, the Sn-containing high melting point bonding layer preferably contains 50% by mass or less of Sn. Moreover, it is preferable that the said Sn containing high melting-point joining layer is an intermetallic compound or alloy containing either Sn-Cu, Sn-Ag, and Sn-Ag-Cu. Further, the first or second side wall member made of a metal material or an inorganic material having a linear expansion coefficient of 80 to 90 (× 10 ⁻⁷ / K) and a melting point of 500 ° C. or higher is an Fe—Ni alloy. It is preferable.

According to a second aspect of the present invention, there is provided an envelope having a rear substrate and a front substrate disposed opposite to the rear substrate, and a plurality of displays connected to wirings provided in the envelope and formed in a matrix. In a method for manufacturing an image display device comprising an element,
First and second side wall members made of a metal material or an inorganic material having a linear expansion coefficient of 80 to 90 (× 10 −7 / K) and a melting point of 500 ° C. or more are formed at the end portions of the back substrate and the front substrate. And the process of
Forming first and second Cu layers having a thickness of 10 to 200 μm on the surfaces of the first and second sidewall members;
A step of arranging Sn alone or a metal material forming Sn and an intermetallic compound or a high-melting-point alloy and Sn between the first and second Cu layers and bonding at 300 ° C. or higher and 450 ° C. or lower; It is a manufacturing method of the image display apparatus characterized by having.

According to the present invention, it is possible to provide an image display device including a bonding portion having a heat resistance of 300 ° C. or higher and a manufacturing method thereof without affecting environmental problems in bonding between glass substrates having a low coefficient of thermal expansion. . In addition, as a result, a good joint is formed and there is no fear of scattering of the metal layer, thereby reliably preventing a short circuit of the wiring portion.

[First Embodiment: Image Display Device]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, an FED will be described as an example of an image display device according to the present embodiment.

  As shown in FIGS. 1 to 3, the FED includes a front substrate 11 and a rear substrate 12 each made of rectangular glass as insulating substrates, and these substrates have a gap of about 1.0 to 3.0 mm. It is placed facing each other. The front substrate 11 and the back substrate 12 constitute a flat rectangular vacuum envelope 10 whose peripheral portions are bonded to each other via a bonding portion 40 and the inside is maintained in a vacuum state.

  The peripheral portions of the front substrate 11 and the rear substrate 12 are coupled to each other by a joint 40. That is, side wall members 13 and 14 that function as a frame are disposed on the bonding surface located at the inner peripheral edge of the front substrate 11 and the bonding surface located at the inner peripheral edge of the rear substrate 12. A Cu-containing high melting point bonding layer such as a CuSn intermetallic compound layer is formed by the reaction between the Cu layers 21 and 22 provided on 14 and a bonding material mainly composed of Sn. The Cu layers 31 and 32 and the CuSn intermetallic compound layer merge to form a bonding layer 34, and further, the bonding layer 34 and the side wall members 13 and 14 form a bonding portion 40.

  A plurality of support members 15 are provided inside the vacuum envelope 10 in order to support an atmospheric pressure load applied to the back substrate 12 and the front substrate 11. These support members 15 extend in a direction parallel to the short side of the vacuum envelope 10 and are arranged at a predetermined interval in a direction parallel to the long side. The shape of the support member 15 is not particularly limited to this, and a columnar support member may be used.

  As shown in FIG. 3, on the inner surface of the back substrate 12, a large number of field emission type electron-emitting devices that emit electron beams are provided as electron emission sources for exciting the phosphor layers R, G, and B, respectively. ing. These electron-emitting devices are arranged in a plurality of columns and a plurality of rows corresponding to each pixel, and function as display devices.

  As described above, since a high voltage is applied to the phosphor screen, high strain point glass is used for the front substrate 11, the rear substrate 12, and the plate glass for the support member 15.

Furthermore, the said junction part 40 is demonstrated in detail.
The joint portion of the present embodiment includes first and second side walls disposed on the respective surfaces of the back substrate and the front substrate, and first and second side surfaces disposed on the surfaces of the side walls. A Cu layer and a bonding layer including an intermetallic compound disposed between the first and second Cu layers are provided.

Thus, the first and second side wall members 13 and 14 separate the vacuum space inside the display device from the outside. Therefore, it is preferable to have materials and dimensions that can maintain mechanical strength and hermeticity. The material is preferably made of a metal material or an inorganic material having a linear expansion coefficient of 80 to 90 (× 10 ⁻⁷ / K) and a melting point of 500 ° C. or higher. Specifically, an Fe—Ni alloy, glass, ceramics, or the like can be used. The front substrate 11 and the rear substrate 12 are each formed of glass, and the glass and the side wall member can be bonded using an inorganic adhesive such as frit glass.
When the linear expansion coefficient is not 80 to 90 (× 10 ⁻⁷ / K) as the side wall material, the difference in expansion coefficient between the front substrate and the rear substrate and the side wall material as the temperature rises during driving of the display device. This is not preferable because thermal distortion is generated due to the occurrence of cracks in the display device.

  First and second Cu layers 21 and 22 are disposed on the surfaces of the first and second side wall members 13 and 14, respectively. The Cu layer material is preferably pure Cu, but may inevitably contain impurities. Moreover, as thickness of these Cu layers, the range of 10-200 micrometers is preferable. When this thickness is less than 10 μm, it is difficult to form a CuSn intermetallic compound layer. On the other hand, when the thickness of the Cu layer is in a range exceeding 200 μm, it is not preferable because it becomes difficult to supply the Cu layer or the supply method is remarkably limited.

  An Sn-containing high melting point bonding layer 33 is disposed between the first and second Cu layers 21 and 22.

  The Sn-containing high melting point bonding layer 33 is formed by reacting or alloying Sn (hereinafter referred to as a first metal component) and another metal that reacts or alloys with Sn (hereinafter referred to as a second metal component). A high melting point intermetallic compound layer or a high melting point alloy layer. Examples of the metal that reacts or alloyed with Sn include Cu, Ag, Ni, and Fe. Among these, a combination of Cu—Sn and Cu—Ag—Sn is preferable. The reason is that the reactivity with Sn is high and the growth rate of the reaction layer is high.

Specifically, the Sn-containing high melting point bonding layer 33 is obtained by reacting or alloying Sn with another metal by heating at a melting point of Sn, that is, a temperature of 232 ° C. or higher. The intermetallic compound is a phase such as Cu6Sn5, Cu3Sn, or Ag3Sn. The melting points of these phases are all 400 ° C. or higher, and have sufficient heat resistance and mechanical strength.
The thickness of this layer is preferably in the range of 10-100 μm. When the thickness of this layer is less than 10 μm, the bonding of the first and second Cu layers may be incomplete, while to form a CuSn intermetallic compound bonding layer exceeding 100 μm, It takes a long time, and an effect commensurate with this cannot be expected, which is not practical.
Note that the Sn-containing high-melting-point bonding layer may have an unclear interface with the Cu layer depending on the manufacturing method, but if the melting point of the Sn-containing layer is 400 ° C. or higher, this layer It doesn't matter if it's not clear.

  In the Sn-containing high melting point bonding layer, the Sn content is preferably 50% by mass or less. If the Sn content exceeds 50% by mass, the bonding layer may have a melting point of 300 ° C. or lower.

The Sn-containing high melting point bonding layer may be composed of a plurality of layers having different compositions. That is, as shown in FIG. 4, although the Sn-containing high melting point bonding layer 33 exists between the first Cu layer 21 and the second Cu layer 22, the Sn-containing high melting point bonding layer 33 has a different composition. You may make it consist of several layers, ie, 43,44,45.
For example, when Cu and Sn are reacted, an intermetallic compound such as η phase (Cu ₆ Sn ₅ ), ε phase (Cu ₃ Sn), or δ phase (Cu _40.5 Sn ₁₁ ) is formed. The η phase has a melting point of 415 ° C., and the ε phase has a melting point of 676 ° C., and the heat resistance after bonding is preferably within a sufficient temperature range.
By configuring the Sn-containing high melting point bonding layer with such a plurality of layers, it becomes possible to perform bonding with heat resistance in a relatively short time.
In such an intermetallic compound, the Sn mass ratio ranges from 20% by mass to 50% by mass. If Sn is less than 20% by mass or exceeds 50% by mass, an intermetallic compound may not be formed, which is not preferable.
In addition, when the Sn mass ratio is low, diffusion of the refractory metal element used as the second metal component is promoted, resulting in a bonding layer with higher strength. Therefore, the mass ratio of Sn is more preferably 50% by mass or less.

In addition, when Ag is used as the second metal component, an intermetallic compound such as Ag ₃ Sn is formed. In order to form such an intermetallic compound, the Sn mass ratio is preferably 10% to 35%.

Further, when Ag and Cu are used as the second metal component, an intermetallic compound having a composition such as Ag ₃ Sn, η phase (Cu ₆ Sn ₅ ), ε phase (Cu ₃ Sn) or δ An intermetallic compound having a composition such as a phase (Cu _40.5 Sn ₁₁ ) is formed to provide a heat-resistant bonding material.

In the intermetallic compound, a part of the constituent elements may be substituted with other elements. For example, when Ag is substituted for Ag ₃ Sn, Ag is substituted for (Ag, Cu) ₃ Sn, and when Ag is substituted for Cu ₃ Sn, Ag is substituted for (Cu, Ag) ₃ Sn, Cu _40.5 Sn ₁₁ In this case, a crystal structure such as (Cu, Ag) _40.5 Sn ₁₁ is obtained.

In the present embodiment, the bonding surface made of Cu on a metal material or an inorganic material such as an Fe—Ni alloy or a glass material provided at the bonding portion between the front substrate and the rear substrate, and Sn or a mass ratio. By using a metal material such as an Sn alloy containing 50% or more of Sn, bonding can be performed even under a high temperature condition of 300 ° C. or higher. In addition, since the glass substrate having a different thermal expansion coefficient and the metal material used for bonding can be bonded without directly reacting, it is possible to prevent the occurrence of cracks due to thermal stress, and a good bonded portion is formed. Since there is no fear of scattering of the metal layer, a short circuit of the wiring portion is surely prevented.

[Second Embodiment: Manufacturing Method]
In the manufacturing method of the image display device according to the present embodiment, the side walls are formed around the edges of the front and rear substrates of the glass on which the phosphor layers and the image display elements are formed, and the side walls of the front and rear substrates are joined. Are manufactured. Hereinafter, this method will be described by dividing it into a phosphor and image display element forming step, a side wall forming step, and a bonding step. In the following description, an FED is described as an example of an image display device, but steps other than the phosphor and image display element forming steps can be similarly adopted in the SED.

(Phosphor and image display element forming step)
First, a phosphor screen is formed on a plate glass serving as a front substrate. In this method, a plate glass having the same size as the front substrate is prepared, and a phosphor layer stripe pattern is formed on the plate glass by a plotter machine. The plate glass on which the phosphor stripe pattern is formed and the plate glass for the front substrate are placed on a positioning jig and set on an exposure table, thereby exposing and developing to produce a phosphor screen.

  Subsequently, wiring is formed on the plate glass for the back substrate. For example, when the plane substrate surface is an XY plane, first, for example, a plurality of wirings extending in the X direction by Ag paste or the like are formed in the effective display area and the peripheral portion of the plate glass, respectively, A plurality of extended wires are formed only on the peripheral edge of the plate glass. Thereafter, an insulating layer is formed on the entire surface of the plate glass so as to overlap the wiring. Next, in the effective display area, the remaining wirings extending in the Y direction are formed on the insulating layer, and are connected to the wiring previously formed only on the peripheral edge of the plate glass.

  Subsequently, an electron-emitting device is formed on the plate glass for the back substrate. In this case, a matrix-like conductive cathode layer is formed on the plate glass and connected to the wiring previously formed only on the peripheral edge of the plate glass. Here, the matrix form means a state in which the matrix is arranged in the X direction (horizontal arrangement) and the Y direction (vertical arrangement) corresponding to the above-described wiring.

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

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

  Next, the insulating film is etched by wet etching or dry etching using the resist pattern and the gate electrode as a mask to form a cavity. Then, after removing the resist pattern, a peeling layer made of, for example, aluminum or nickel is formed on the gate electrode by performing electron beam evaporation from a direction inclined at a predetermined angle with respect to the back substrate surface.

  Thereafter, for example, molybdenum is vapor-deposited as a cathode forming material by an electron beam vapor deposition method from a direction perpendicular to the surface of the back substrate 12. Thereby, an electron-emitting device is formed inside each cavity. Subsequently, the release layer is removed together with the metal film formed thereon by a lift-off method.

Next, a plurality of supporting members are bonded to the back substrate by the low melting point glass 30 in the atmosphere.
Through the above steps, a front substrate and a rear substrate on which a phosphor and a plurality of image display elements are formed are created.

(Side wall member forming process)
Next, side wall members are arranged and fixed to the end portions of the back substrate and the front substrate so as to surround the phosphor layer and the image display element. The side wall member is made of a metal material or an inorganic material having a linear expansion coefficient of 80 to 90 (× 10 ⁻⁷ / K) and a melting point of 500 ° C. or more, and specifically, an Fe—Ni alloy. It is made of a material such as glass or ceramics. This member is fixed to the front substrate or the rear substrate with an inorganic adhesive such as frit glass.

(Joining process)
Next, a Cu layer is formed on the upper surface of the side wall member formed by the above process. For the formation of the Cu layer, a known film formation method such as a method of forming by chemical plating on the sidewall member surface, a method of forming a film by physical means such as vapor deposition or sputtering, or a method of forming a film by welding Cu foil is adopted. can do.
Next, a material for forming the Sn-containing high melting point bonding layer is disposed on the surface of the Cu layer. This layer is made of Sn and a high melting point intermetallic compound or a high melting point alloy formed of another metal.
In order to form this layer, the following method can be employed.
(1) A method of forming a Sn layer on the Cu layer surface and heating to form a Sn-containing refractory bonding layer.
(2) A method of forming a Sn-containing refractory bonding layer by forming Sn and another metal layer on the surface of the Cu layer and heating the layer.
Hereinafter, these methods will be described.

  In the first bonding method of the present embodiment, the step of applying an Sn film to the surface of the first Cu layer and the second Cu layer in close contact with the surface of the Sn film are performed at 300 ° C. or higher and 450 ° C. or lower. This is a bonding method including a step of heating, closely adhering, and bonding. The bonding temperature is more preferably 300 ° C. or higher and 400 ° C. or lower. When the bonding temperature is lower than this, the bonding layer material does not sufficiently react or alloy, and the heat resistance is not improved sufficiently. On the other hand, when the bonding temperature exceeds the above range, there is a large possibility that the member to be bonded is thermally damaged, which is not preferable.

In the bonding step in this bonding method, the bonding layer material formed on the surface of the first Cu layer may be a Sn foil, or Sn may be sputtered, vacuum deposited, ion plated, electron You may provide using physical thin film formation techniques, such as a beam evaporation method. Furthermore, a chemical plating method can also be employed.
In this method, the amount of the first and second Cu needs to be larger than the amount of Sn. If the amount of Sn is less than the amount of Cu, unreacted Sn remains, which may reduce the heat resistance.

In the bonding step, it is more preferable that the heating time is 5 minutes to 1 hour. If the heating time is shorter than this, the intermetallic compound or alloy is not sufficiently formed, and the heat resistance is not sufficient. On the other hand, even if heating exceeds the above range, the effect of improving heat resistance commensurate with the increase in heating time cannot be expected, which is uneconomical.
The bonding step may be performed in an air atmosphere, but when a bonding material including a metal that is easily oxidized is used, it is preferable to perform heating in a non-oxidizing atmosphere such as nitrogen. Furthermore, it is more preferable to perform heating in a reducing atmosphere containing hydrogen.

  The thickness of the bonding layer is preferably in the range of 1 μm or more and 50 μm or less. In the case of stratification over a plurality of layers, the total film thickness is preferably in the above range. When the bonding layer is thinner than 1 μm, it is difficult to ensure good bonding properties. When the bonding layer is 50 μm or more, the intermetallic compound may not be completely formed within the bonding time. Absent.

  According to the bonding method of the present embodiment, since a bonding layer having a heat resistance of 270 ° C. or higher is formed, the heat resistance of the bonding layer can be maintained even under a high temperature condition of 270 ° C. In addition, in the bonding layer material, the constituent elements of the first member to be bonded or the second member to be bonded are dissolved in the bonding layer, or the bonding material constituting elements in the bonding layer and each bonded portion. An intermetallic compound phase or the like composed of the layer material constituent elements may be generated. As a result, it is possible to obtain a joined body having good mechanical strength even under high temperature conditions.

In the second bonding method of the present embodiment, Sn (hereinafter referred to as a first metal component) and a metal component that reacts or alloys with the first Cu layer surface (hereinafter referred to as a second metal component) are formed on the surface of the first Cu layer. And a step of providing a film by using them individually or in combination, and a step of bringing the second Cu layer into close contact with the surface and heating at 300 ° C. to 450 ° C. for bonding. The bonding temperature is more preferably 300 ° C. or higher and 400 ° C. or lower. When the bonding temperature is lower than this, the bonding layer material does not sufficiently react or alloy, and the heat resistance is not improved sufficiently. On the other hand, when the bonding temperature exceeds the above range, there is a large possibility that the member to be bonded is thermally damaged, which is not preferable.
That is, in the bonding method of the present embodiment, at least one layer of a Sn film and a metal material film having a melting point higher than Sn are applied to the surface of the first Cu layer, and the above-described process is applied. The bonding method is characterized by heating at a temperature of 250 ° C. or higher and 450 ° C. or lower while pressing the second Cu layer in close contact with the surface of the metal material film.

  In the bonding step in this bonding method, the bonding layer material formed on the surface of the first Cu layer may be mounted with foils of the first and second metal components, respectively. The metal foil may be previously reacted with the Cu layer as preheating. At that time, by using the ultrasonic soldering method, it is possible to obtain a good bonded state without using a flux. Moreover, you may provide these metal components using physical thin film formation techniques, such as sputtering method, a vacuum evaporation method, an ion plating, and an electron beam evaporation method. Furthermore, a chemical plating method may be employed to provide the film.

  The thickness of the thin film bonding material is preferably in the range of 10 μm to 300 μm. When thinning over a plurality of layers, the total film thickness is preferably in the above range. When the thickness of the bonding material is less than 101 μm, it becomes difficult to ensure good bonding properties, and when it is 300 μm or more, the intermetallic compound may not be completely formed within the allowable bonding time. Therefore, it is not preferable.

  In the joining step, the heating time may be 5 minutes to 1 hour. The bonding step is performed in a vacuum.

In the above embodiment, an example in which the bonding layer material is formed on one surface of the two Cu layers has been shown. However, the bonding layer material is formed on the surfaces of both the first Cu layer and the second Cu layer. May be.
In this case, the two bonding layer materials may be layers having the same composition, or layers having different compositions. The solder joint of this embodiment can be formed by adjusting the composition of each layer so that the joint layer material after the final solder joint has the composition of the joint layer of the present embodiment. it can.
Moreover, the thickness of the thin film formed in each base-material surface can be set, respectively so that those total amounts may become the range of 10 micrometers or more and 300 micrometers or less.

  The bonding step is preferably performed in a vacuum atmosphere because the inside of the envelope of the image display device needs to be kept in vacuum.

[Other variations]
In the above embodiment, an example of an FED is shown as the display element. However, the present invention can also be applied to a display device such as an SED that has a built-in vacuum space and is exposed to high temperatures.

Hereinafter, the present invention will be described with reference to examples. FIG. 4 is a partial cross-sectional view of the envelope of the image display device created by the present invention.
The front substrate 11 was created using a high strain point glass having a thickness of 3 mm, a length of 40 cm, and a width of 75 cm. A phosphor screen was formed on the surface of the substrate, and then the first wall surface member 13 was fixed to the peripheral edge using a frit glass 41. As the wall member, an Fe—Ni alloy was used. Next, a first Cu layer 21 having a thickness of 100 μm was placed on the surface of the wall surface member 13 and heated for metallization.
On the other hand, the back substrate 12 was prepared using high strain point glass having a thickness of 3 mm, a length of 50 cm, and a width of 85 cm. An image display element was formed on the inner surface of the rear substrate 12 in accordance with a conventional method, and then the second wall member 14 was fixed to the peripheral edge using a frit glass 42. As the wall member, an Fe—Ni alloy was used. A second Cu foil 22 having a thickness of 100 μm was placed on the surface of the wall member 14 and heated for metallization.
Next, in a vacuum vessel, a 100 μm thick Sn foil is placed on the surface of the first copper foil 21, and the second Cu layer 22 on the back substrate 12 is brought into close contact with the surface and pressed. Then, bonding was performed by heating at 400 ° C. for 30 minutes.
As a result, as shown in FIG. 4, the Sn-containing high melting point bonding layer 33 was obtained as a composite layer composed of three layers of Cu3Sn, Cu6Sn5, and Cu3Sn phases. The heat resistance temperature of the bonding layer was 300 ° C. or higher.

It is a perspective view which shows the external appearance of the envelope of the image display apparatus of this invention. It is the perspective view which removed the front substrate in order to show the inside of the image display apparatus of this invention. It is sectional drawing of the envelope of the image display apparatus of this invention. It is sectional drawing to which the junction part of the Example of this invention was expanded.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Vacuum envelope 11 ... Front substrate 12 ... Back substrate 13 ... 1st side wall member 14 ... 2nd side wall member 21 ... 1st Cu layer 22 ... 2nd Cu layer 33 ... Sn containing high melting-point joining layer 34 ... Joint layer 40 ... Joint part 41 ... Frit glass 42 ... Frit glass

Claims (5)

An envelope having a rear substrate and a front substrate disposed opposite to and bonded to the rear substrate; and a plurality of display elements connected to the wiring provided in the envelope and formed in a matrix. In the provided image display device,
The junction between the back substrate and the front substrate is
A first side wall member made of a metal material or an inorganic material having a linear expansion coefficient of 80 to 90 (× 10 ⁻⁷ / K) formed on the back substrate surface and a melting point of 500 ° C. or higher;
A first Cu layer formed on a surface of the first sidewall member and having a thickness of 10 to 200 μm;
An Sn-containing refractory bonding layer formed on the surface of the first Cu layer and having a thickness of 10 to 100 μm;
A second Cu layer formed on the surface of the Sn-containing high melting point bonding layer and having a thickness of 10 to 200 μm;
A linear or thermal expansion coefficient formed between the surface of the second Cu layer and the front substrate is 80 to 90 (× 10 ⁻⁷ / K), and is made of a metal material or an inorganic material having a melting point of 500 ° C. or higher. An image display device comprising: 2 side wall members.   The image display apparatus according to claim 1, wherein the Sn-containing high melting point bonding layer contains 50 mass% or less of Sn.   3. The Sn-containing high melting point bonding layer is an intermetallic compound or alloy containing any of Sn—Cu, Sn—Ag, and Sn—Ag—Cu. Image display device. The first or second side wall member made of a metal material or an inorganic material having a linear expansion coefficient of 80 to 90 (× 10 ⁻⁷ / K) and a melting point of 500 ° C. or higher is an Fe—Ni alloy. The image display device according to any one of claims 1 to 3, wherein the image display device is characterized. An image including an envelope having a rear substrate and a front substrate disposed opposite to the rear substrate, and a plurality of display elements connected to the wiring provided in the envelope and formed in a matrix. In the manufacturing method of the display device,
First and second side wall members made of a metal material or an inorganic material having a linear expansion coefficient of 80 to 90 (× 10 −7 / K) and a melting point of 500 ° C. or more are formed at the end portions of the back substrate and the front substrate. And a process of
Forming first and second Cu layers having a thickness of 10 to 200 μm on the surfaces of the first and second sidewall members;
A step of arranging Sn alone or a metal material forming Sn and an intermetallic compound or a high-melting-point alloy and Sn between the first and second Cu layers and bonding at 300 ° C. or higher and 450 ° C. or lower; A method for manufacturing an image display device, comprising:

Images