JPH09213230A - Joint body of electrode plates and metal buried ceramics, and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To joint electric plates and metal burried ceramics solidly without breaking a ceramics by the shock of the heat of a laser beam, by laminating electrode plates on the metal buried ceramics, and welding and fixing the electrode plates, and the buried metals buried to the metal buried ceramics. SOLUTION: Two electrode plates 4 are provided by placing a ceramics 31 at the center, the laser beam is radiated to the electrode plate 4 from a YAG laser device 7, and the metal chips 2 buried to the metal buried ceramics 31 are melted so as to joint the electrode plate 4 and the buried metals. Such an operation is carried out to both side surfaces of the metal buried ceramics 31 so as to compose a jointed body 6. Consequently, they can be jointed solidly without breaking the ceramics part by the shock of the heat of the laser beam. Since the jointing operation is carried out at a normal temperature, a high accuracy of jointing can be carried out generating no warpage, after the ceramics 31 is jointed to the electrode plates 4 with the different thermal expansion coefficient.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bonded body of an electrode plate and an insulator used for an electrode structure of an image display device.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. 61-114436 discloses a joining method as shown in FIG. 10
An electrode plate 0 has an electron beam passage hole (not shown). 101 is a core material made of a metal plate, 102 is an insulating film, and 103 is a bonding material made of low melting point glass,
Two electrode plates 100 with a bonding material 103, about 500 ℃
Then, the whole is heated to melt and bond the bonding material 103.

[0003]

When a plurality of electrodes are laminated to form an electrode assembly by using the conventional technique shown in FIG. 6 and used in an image display device, the electrode plate 100 is used in the same lot. Variations in the coefficient of thermal expansion and variations in the coefficient of thermal expansion occur due to different manufacturing lots. For this reason, the two electrode plates 10 that are bonded together are bonded and fixed at a high temperature, and the two electrode plates 10 that are bonded to each other are cooled to room temperature.
0, the amount of thermal contraction of the electrode plate 100 having a large coefficient of thermal expansion is large, so that the electrode side having a large coefficient of thermal expansion is warped in a concave shape.

If the electrode plate 100 has a warp, a color shift occurs due to a landing shift of the electron beam, which causes a problem that the image quality of the image display device deteriorates. Also, the bonding material 1
03 and the insulating film 102 are made of a frit glass material, the peel strength is small, and when stress is applied to the frit glass during manufacturing / handling, the frit glass is peeled off, and fragments of the peeled glass scatter, resulting in the electrode plate. 100
Attached to the electron beam passage hole, and the electron beam passage hole is clogged. Therefore, there is a problem that an image defect is caused by a defective electron beam passage.

As a means for solving these problems, a method is conceivable in which a metal film is formed on the surface of an insulating base material by thermal spraying or plating, and the metal surface and the electrode plate are welded and fixed at room temperature. However, when a metal film is formed on an insulating base material such as ceramics by the above method and the metal film and the electrode plate are laser-welded, if the metal film is about 100 μm, the welding strength with the metal film is insufficient, so Peel with a weak force.

When the metal film is thinner, the heat of laser welding causes thermal destruction of the ceramics. On the other hand, when the metal film is formed thicker, it is difficult to perform plating, and the thermal spraying method has problems such as weak bonding strength with ceramics and difficulty in obtaining uniform film thickness.

The present invention is a high quality image display device which eliminates image defects due to warpage of electrode plates caused by high temperature bonding of electrode plates having slightly different coefficients of thermal expansion and scattering of debris caused by insufficient strength of the bonding material. In order to realize the above, an object of the present invention is to provide a structure of a bonding base material that enables the electrode plate and the insulating base material to be bonded at room temperature by laser welding or the like, and a manufacturing method thereof.

[0008]

A bonded body of an electrode plate and a metal-embedded ceramic according to claim 1, wherein the electrode plate is laminated on the metal-embedded ceramic in which a metal is embedded on the surface of the ceramic, The embedded metal embedded in the metal-embedded ceramic is welded and fixed.

According to a second aspect of the present invention, there is provided a method for manufacturing a joined body of an electrode plate and a metal-embedded ceramic, wherein the electrode plate is laminated on the metal-embedded ceramic and the electrode plate is irradiated with a beam to be embedded in the metal-embedded ceramic. The embedded metal is melted and the electrode plate and the embedded metal are joined together at room temperature.

[0010]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIG. 1 to 4 show a metal-embedded ceramic used in a bonded body of an electrode plate and a metal-embedded ceramic according to the present invention.

FIG. 1 is a sectional view of the metal-embedded ceramics after sintering, and FIG. 2 shows a manufacturing process of the metal-embedded ceramics. 3 and 4 show changes in shrinkage of the metal-embedded ceramics.

In FIG. 2, reference numerals 1a and 1b denote first and second green sheets (unfired ceramic sheets) having through holes 1c. In the state where the first and second green sheets 1a and 1b are stacked as shown in FIG. 2A, the through hole 1c of the first green sheet 1a and the through hole 1c of the second green sheet 1b are stacked. Through holes 1c are formed at different positions so that they do not communicate with each other.

First and second green sheets 1a and 1b
Is composed of alumina as the main component and silica, magnesia, organic solvents, binders such as solvents are added, and
It has been finished to a thickness of m. When fired at a sintering temperature Ts = 1500 ° C, a ceramic having a coefficient of thermal expansion αc = 70 × 10 ^-7 / ° C. The diameter of the through hole 1c is a diameter d ₁ = 500 μm at room temperature (for example, 25 ° C.).

The laminated first and second green sheets 1
When firing a and 1b, the metal chip 2 is inserted into each through hole 1c. The metal tip 2 is made of molybdenum and has a diameter of 450 μm and a length of about 200 μm at room temperature.

Molybdenum has a sintering temperature T of ceramics.
A material with a melting point of 2622 ° C, which is higher than
= 55 × 10 ^-7 / ° C. In addition, the first and second green sheets 1a and 1b stacked upon firing are pressed before or after the metal chip 2 is inserted.

Here, the metal chip 2 and the through hole 1 before firing
As for the relationship of c, as shown in FIG.
Although there is a gap of 0 μm, by heating to the sintering temperature Ts in the state of FIG. 2 (A), the diameter of the metal tip 2 at the sintering temperature Ts is as shown in FIG. 3 (B). Due to thermal expansion, d ₂ = 453.65 μm, and the through hole 1 of the green sheet
Difference of c from the diameter d ₁ = 500 μm at room temperature δ ₀ = d ₁ −d
₂ is 46.35 μm.

The firing shrinkage ratio P of the green sheet at the sintering temperature Ts is S1, the dimension of the green sheet at room temperature,
When the dimension after firing at the sintering temperature Ts is S2,
When P = (S1−S2) / S1, the firing shrinkage amount is δ _S
= D ₁ · P. For example, if a material having a firing shrinkage of 14% is used, the size of the through hole 1c shrinks by 70 μm after firing and the diameter thereof becomes 430 μm. At this time, the relationship between the metal chip 2 and the through hole 1c becomes a tight state of 23.65 μm as shown in FIG.

At this time, the stress at which the ceramic tightens the metal does not exceed the fracture stress of the ceramic by δ _S
And δ ₀ are selected. Further, when the temperature returns to room temperature, the diameter of the through hole 1c shown in FIG.
Shrink at 70 × 10 ^-7 / ° C to 425.56 μm, and the metal tip 2 similarly shrinks at αm = 55 × 10 ^-7 / ° C with a diameter of 450.
μm, and the relationship between them is approximately as shown in (C) of FIG.
It becomes a tight state of 24.44 μm.

Therefore, the metal chip 2 and the through hole 1c are firmly connected to each other, and the fired ceramics 8 is formed as shown in FIG.
The metal-embedded ceramics 31 having the metal chip 2 embedded therein is completed.

The firing shrinkage of ceramics can be adjusted to about 5 to 20% by changing the binder material and the compounding ratio. Further, although an example in which molybdenum is used for the metal tip 2 is shown, it is also possible to use a material having another thermal expansion coefficient.

The hole diameter after firing can be changed by changing the shrinkage rate of the ceramics, and the combination of the thermal expansion coefficient of the ceramics used and the thermal expansion coefficient of the metal chip 2 can be changed to change the metal chip. The tightening force between 2 and the ceramics can be optimized, cracks due to the stress of the ceramics can be eliminated, and a strongly fixed metal-embedded ceramics 31 can be realized.

Although the above description is for d ₁ <d ₂ + δ _S , it may be d ₁ > d ₂ + δ _S. d ₁ > d ₂ +
When δ _S is reached, a gap is generated between the ceramic and the metal at the temperature Ts as shown in FIG. Ts
The coefficient of thermal expansion of the ceramic and the metal may be selected so that the required tightness is generated between the ceramic and the metal when the temperature is returned to room temperature.

FIG. 5 shows a manufacturing state of a joined body of the electrode plate 4 and the metal-embedded ceramics 31 manufactured as described above with the electrode plate 4. The ceramics 31 has the composition and dimensions described in the above example, and the electrode plate 4 is "42Ni-6C".
r-Fe alloy ”and its thickness is about 200 μm.

Two electrode plates 4 are arranged with the ceramics 31 at the center, and the electrode plate 4 is irradiated with a laser beam 7a from a YAG laser device 7 to melt the metal chips 2 embedded in the metal-embedded ceramics. The electrode plate 4 and the embedded metal are joined. Here, a laser beam 7a was applied to each of the metal chips 2 to apply heat of 5.3 J to bond them.

This operation is performed by the metal-embedded ceramics 31.
On both sides to form the bonded body 6 shown in FIG. Further, since the positions of the metal chips 2 embedded in the one surface and the other surface of the ceramics 31 are displaced from each other, the required insulation performance can be sufficiently satisfied.

Since the metal tip 2 has a cylindrical shape and has a predetermined volume, the ceramic tip can be firmly bonded without being destroyed by the impact of the heat of the laser when the laser light is irradiated.
Since the bonding is performed at room temperature, the electrode plates 4 having different thermal expansion coefficients do not warp even after being bonded, and highly accurate bonding can be realized.

Further, since the metal plate strongly embedded in the ceramic and the electrode plate are bonded to each other without using a bonding member such as frit glass having a low strength, it is possible to prevent the frit glass from peeling or scattering as in the conventional case. It does not cause any inconvenience.

In the above-mentioned embodiment, the through holes 1c are formed in the first and second green sheets 1a and 1b respectively, and the through holes 1c are laminated to manufacture the single green sheet. Forming a first non-through hole toward the other surface,
A second non-through hole is formed from the other surface of the green sheet toward the one surface, and a metal chip similar to that of the above-mentioned embodiment is inserted into the first and second non-through holes. The same ceramics 31 can be manufactured by firing by firing. By shifting the positions of the first non-through hole and the second non-through hole, it is possible to sufficiently satisfy the required insulation performance as in the above case.

However, in terms of yield, the method of manufacturing by forming the through holes 1c in the first and second green sheets 1a and 1b has better productivity. In each of the above-described embodiments, the case where the electrode plates are welded to both surfaces of the metal-embedded ceramics has been described as an example, but the one in which the electrode plates are welded to the metal-embedded ceramics and the electrode plate is welded to this one surface. In the case where the bonded assembly is stacked to form an electrode assembly, a through hole is formed only in one of the first and second green sheets,
By stacking the first green sheet having the through holes and the second green sheet having no through holes and firing the same with the same metal inserted in the through holes of the first green sheet, the The metal-embedded ceramics can be manufactured with a good yield.

[0030]

As described above, in the bonded body of the electrode plate and the metal-embedded ceramics of the present invention, the electrode plate is laminated on the metal-embedded ceramic in which a metal is embedded on the surface of the ceramic, and the electrode plate and the metal-embedded ceramic are embedded. Since the embedded metal embedded in the ceramics was fixed by welding, it is possible to weld and join at room temperature to form an electrode assembly, and by using a metal-embedded ceramic in which a required volume of metal is embedded, When the embedded metal and the electrode plate are joined by a laser beam, for example, the ceramics can be joined firmly without being destroyed by the impact of the heat of the laser light.

Further, according to the method of manufacturing the bonded body of the electrode plate and the metal-embedded ceramic, the electrode plate is laminated on the metal-embedded ceramic, and the electrode plate is irradiated with a beam to be embedded in the metal-embedded ceramic. Since the embedded metal is melted and the electrode plate and the embedded metal are joined in an environment at room temperature, the warpage of the electrode plate caused by the high temperature joining of the electrode plates having slightly different thermal expansion coefficients and the insufficient strength of the joining material are caused. It is possible to eliminate the scattering of debris.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a metal-embedded ceramic used in a joined body of the present invention.

FIG. 2 is a process diagram of a method for producing a metal-embedded ceramic used in the joined body of the present invention.

FIG. 3 is a shrinkage change diagram of a material in a manufacturing process of a metal-embedded ceramics used for a joined body of the present invention.

FIG. 4 is a shrinkage change diagram of a material in a manufacturing process of a metal-embedded ceramic used in the joined body of the present invention.

FIG. 5 is an explanatory view of the manufacturing process of the joined body of the present invention.

FIG. 6 is a sectional view of an electrode structure of a conventional flat panel image display device.

[Explanation of symbols]

 2 Metal chip 4 Electrode plate 31 Metal embedded ceramics

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Fumio Yamazaki 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor, Isamu 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. 72) Inventor Hiroshi Matsumoto 22 Kyocera Co., Ltd. at 5 Inoue Kitanouemachi, Yamashina-ku, Kyoto (72) Inventor Koji Yamamoto 22 Kyocera Co., Ltd. at 5 Higashinokitainoue-cho, Yamashina, Kyoto

Claims (2)

[Claims] 1. An electrode plate and a metal-embedded ceramic in which an electrode plate is laminated on a metal-embedded ceramic in which a metal is embedded on the surface of the ceramic, and the electrode plate and the embedded metal embedded in the metal-embedded ceramic are fixed by welding. Zygote. 2. An electrode plate is laminated on a metal-embedded ceramic, and the electrode plate is irradiated with a beam to melt the embedded metal embedded in the metal-embedded ceramic so that the electrode plate and the embedded metal are kept at room temperature. A method for manufacturing a bonded body of an electrode plate and a metal-embedded ceramic that is bonded in an environment.