JP2602766Y2 - Jig for brazing - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brazing jig for setting and fixing both positions when brazing a metal and an insulating member.

[0002]

2. Description of the Related Art Conventionally, when joining a metal to an insulating member such as ceramics, brazing has been performed. This is a method in which a brazing material having a melting point lower than that of the metal to be joined and the insulating member is sandwiched between the joining portions, and the brazing material is melted by heating at a high temperature of 800 to 1000 ° C. and joined. In this heat treatment, a brazing jig (hereinafter abbreviated as a jig) is used to set and fix the positions of the metal and the insulating member.

Conventionally, high-density carbon with high heat resistance and good workability has been used for this jig in order to repeat rapid heating and cooling during brazing. Since carbon adheres to the insulating member, and the adhered substance cannot be completely removed by washing, there is a disadvantage that the insulation resistance is reduced.

Accordingly, a jig made of an alumina or alumina-silica porous body is used as a material having high heat resistance and not being attached to a metal or an insulating member because the surface member of the jig is peeled off. (Japanese Unexamined Patent Publication No. Hei 3-1535)
No. 78).

[0005]

However, in the above-mentioned porous material, if it is used several times, each member cannot be set due to the influence of heat, or the melting point of glass or the like used as a sintering aid. There is a problem that a substance having a low melting point is melted and adheres to the brazing member.

[0006] In addition, there is another problem that chips and cracks are liable to occur at the time of transportation or brazing because of low strength.

[0007]

In view of the above problems, the present invention provides a porous ceramic body having an Al ₂ O ₃ content of 99.0% by weight or more, a porosity of 30 to 60%, and an average pore diameter of 5 μm or less. This is a brazing jig made of

Here, the ceramic having an Al ₂ O ₃ content of 99.0% by weight or more is used. When the content is less than 99.0% by weight, a substance having a low melting point tends to be melted.
And chipping and cracking occur due to the reduced strength,
This is because the number of usable times is reduced.

The reason why the porosity of the jig is 30 to 60% is that if the porosity is less than 30%, heat conduction from the jig surface to the inside becomes worse and only the temperature near the surface becomes higher. Expansion near the surface increases, resulting in cracks,
This is because it becomes impossible to set each member. On the other hand, 60%
If it is larger than this, the strength is weakened, and as a result, chipping or cracking is likely to occur during transportation or assembly.

[0010]

Embodiments of the present invention will be described below.

Embodiment 1 As shown in the perspective view of FIG. 1 (a) and the sectional view of FIG. 1 (b), the jig 1 of the present invention has a first flange portion 3 on the bottom surface of a cylindrical portion 2 and a bottom surface thereof. And has a second flange portion 4, and the whole has an Al ₂ O ₃ content of 99.0% by weight or more and a porosity of 30 to 6
It is made of a 0% porous ceramic body.

For example, as a product to which the jig 1 is applied, there is an envelope for a current introducing terminal. This envelope is shown in FIG.
As shown in the perspective view of (a) and the cross-sectional view of (b), a distal end member 6 having a flange 5 at a lower part of a metal cylindrical body, which is joined to the bottom surface of the flange 5 and provided for heat dissipation. An intermediate member 8 made of alumina ceramics after metallizing treatment having a projection 7 provided thereon, and a rear end member 10 having one end 9 joined to the bottom surface of the intermediate member 8 by a metal cylindrical body. The members are fixed by brazing. However, the front end member 6 and the rear end member 10 are made of a metal having a melting point of 1000 ° C. or more, such as iron.

When brazing is performed using the jig 1 of the present invention, as shown in FIG. 3, the jig 1 and the respective members are assembled into the cylindrical portion 2 by the tip member 6 and the intermediate member 8. The one end 9 of the rear end member 10 is fixed, the lower part of the rear end member 10 is fixed to the first flange 3, and the second flange 4 serves as a mount for the rear end member 10. Here, the cavity 11 with the jig 1 formed in the middle portion of the rear end member 10 minimizes the contact between the jig 1 and the rear end member 10 so that the jig 1 is not affected by the heat. In order to Then, with each member fixed with the jig 1, a brazing material 12 such as silver or copper is sandwiched between respective joining portions between the leading end member 6 and the intermediate member 8 and between the intermediate member 8 and the rear end member 10. It is brazed at about 1000 ° C. for about 2 hours.

Here, as a raw material of the jig 1, water, an organic binder, and a sintering aid such as glass and silica are added to alumina powder, mixed, and spray-dried.
A granulate with a size of 0 μm is used. At this time, Al ₂ O
_In order for the content of ₃ to be 99.0% by weight or more, the sintering aid must be in a proportion of 1% by weight or less based on 99% by weight of Al ₂ O ₃ . Then, this granulated material is filled into a rubber mold and subjected to rubber press molding in which a material is formed by applying water pressure in a high-pressure cylinder, or mechanical press molding in which powder is filled in a mold and pressure is applied by upper and lower punches. The pressure at this time is 8
It should be 00 to 1200 kg / cm ² . After that, it is cut into a desired shape of the jig 1. 1200 to 16
Sinter at 00 ° C and finish by grinding the parts that require precision. After that, heat treatment is performed at about 1000 ° C. to complete the process. This heat treatment can remove dirt, oil, and deposits in the process.

The jig 1 manufactured by the above process becomes a porous body because the molding pressure and the sintering temperature are lowered, and finally, the Al ₂ O ₃ content is 99.0% by weight or more, and the porosity is 30.
６０60%, the average pore diameter on the surface is 1 μm or less.

Here, the average pore diameter on the surface of the jig 1 is 5
It is preferable that the thickness be not more than μm. This is because, if the average pore diameter is larger than 5 μm, the powder or dust or the like peeled off from each member on the surface of the jig 1 is clogged in the pores, and the porosity is reduced. The average pore diameter and the porosity can be changed depending on the pressure during molding and the temperature and time during firing. In addition, a porous body having a predetermined porosity and an average pore diameter can be obtained by previously mixing particles of an organic substance or the like which are burned off during firing in the raw material. The porosity is measured by the water absorption, which is a percentage of the original mass of water that can be absorbed by the material. It was measured by a mercury intrusion method for measuring the relationship between the amounts (see JISC2141).

For example, Al manufactured by sintering at a molding pressure of 800 kg / cm ² and a sintering temperature of 1350 ° C.
₂ O ₃ content 99.0 wt%, 35% porosity, repeating the brazing using average pore size 1μm or less of the jig 1 of the surface, even after 100 times of the number of times of use, the was greatest expansion The 1 flange 3 had a shrinkage of 50 μm or less, which was a sufficiently usable range.

Experimental Example 1 Here, using the jig 1 and each member according to the above embodiment,
Experiments were performed to determine the optimal percentage of Al ₂ O ₃ content. As shown in Table 1, the jig 1 was formed by changing the Al ₂ O ₃ content to 85.0% by weight, 95.0% by weight, 98.0% by weight, and 99.0% by weight. A durability experiment was performed using the same. However, the difference in Al ₂ O ₃ content
By changing the mixing ratio of the sintering aid to Al ₂ O ₃ contained in the granules.

The size of the jig 1 is such that the diameter of the column 2 is 3 cm and the height is 6 cm, the diameter of the first flange 3 is 5 cm and the height is 2 cm, and the diameter of the second flange 4 is 9 cm and the height is 9 cm. The experiment was conducted under the conditions of 1 cm, porosity 35%, average pore diameter 1 μm or less, and the brazing material 12 being silver.

Here, the use limit temperature is determined when the ceramic material is placed on the jig 1 and the temperature is raised in the furnace, and the sintering aid such as glass melts out of the jig 1 and adheres to the porcelain. Temperature. Also, the strength of the jig 1
Was used to examine the bending strength. Further, the number of usable times is defined as the number of times that the brazing process is performed once, and it is determined that it is inappropriate to use each of the members for setting due to chipping, cracking, bonding with the members, or the like.

[0021]

[Table 1]

From Table 1, it can be seen that the higher the Al ₂ O ₃ content of the jig 1, the higher the service limit temperature becomes. The Al ₂ O ₃ content of 85.0% by weight is 1000 ° C. and the 99.0% by weight is 160 ° C.
It turns out that it becomes 0 degreeC. Considering that the brazing temperature will be about 1000 ° C., it can be seen that 85.0% by weight cannot be used. Furthermore, the operating temperature limit is 1000 ° C
Considering the durability, it is more preferable that the use limit temperature is higher than the repeated use several times even if it is higher. The content is preferably larger than 85.0% by weight, more preferably 99.0% by weight. It turns out that it is above.

The bending strength (unit: kg / cm ² ) increases as the Al ₂ O ₃ content of the jig 1 increases,
It can be seen that 85.0% by weight is 400 and 99.0% by weight is 500. Here, if the strength is low, chips and cracks are likely to occur at the time of transportation or brazing assembly, so that even with the same porosity, the higher the bending strength, the better,
It is understood that the content is preferably 99.0% by weight or more.

[0024] Then, usable count of the jig 1 of the Al ₂ O ₃ content, whereas those of the content of Al ₂ O ₃ 98.0% by weight or less is 80 or less, Al ₂ O ₃ containing Quantity 9
It can be seen that the case of 9.0% by weight rapidly increased to 200. This shows that the Al ₂ O ₃ content of 99.0% by weight is good.

After all, when all are judged comprehensively, Al ₂
It can be seen that when the O ₃ content is 99.0% by weight or more, the respective values of the service limit temperature, the bending strength, and the number of usable times are improved.

Experimental Example 2 Here, using the jig 1 and the members according to the above embodiment,
An experiment was conducted to determine the optimum porosity when the Al ₂ O ₃ content was 99.0% by weight.

As shown in Table 2, the jig 1 was constructed by changing the porosity variously, and an experiment of the number of usable times was performed using these jigs. However, the difference in the porosity depends on changing the molding pressure and the firing temperature.

In the experiment, the size of the jig 1 was the same as that of the experimental example 1, and the porosity was 1 μm or less, and the brazing material 12 was silver.

The number of usable times is determined by one step of brazing.
The number of times was defined as the number of times until it was determined that it was inappropriate to use each member for setting due to chipping, cracking, adhesion to the member, or the like. Table 2 shows the results.

[0030]

[Table 2]

According to Table 2, the number of usable times of each porosity is 2
It can be seen that 96% or less for 0% or less, 208 for 30%, 200 for 40%, 160 for 50%, 137 for 60%, and 53 or less for 70% or more.

Here, if the porosity is low, heat conduction from the jig surface to the inside becomes poor, and only the temperature near the surface increases, so that the expansion especially near the surface increases, and as a result, cracks occur. As a result, when the porosity is high, the strength is weakened. As a result, chips and cracks are likely to be generated at the time of assembling.
Because the number of times changes greatly between% and 70%,
It turns out that 30-60% is good.

Furthermore, since 30% and 40% are considerably larger than the others, ie, 200 or more, it is understood that 30% or more and 40% or less are more preferable.

Embodiment 2 Another embodiment of the present invention will be described.

As shown in FIG. 4, the jig 21 has a shape in which a square frame 23 is provided on a square base 22.

For example, as a product to which the jig 21 is applied, as shown in FIG. 5, a ceramic rectangular base 25 having a concave portion 24 for accommodating a semiconductor element and the like, 25, a plurality of lead pins 26
There is a semiconductor element storage package to which is attached.

When the lead pins 26 are brazed to the base 25 using the jig 21, as shown in the plan view of FIG. 6A and the cross-sectional view of FIG. The substrate 25 is completely fixed to the substrate. Here, this jig 21
Was manufactured in the same process as in Example 1 described above, and had an Al ₂ O ₃ content of 99.0% by weight, a porosity of 35%, and a pore size of 1 μm.
Hereinafter, the brazing material was copper, the base 25 was ceramics, and the lead pins 26 were kovar.

As a result of actual use, the surface of the jig 21 did not adhere to the substrate 25 unlike conventional carbon products, and no chipping or cracking occurred even after 100 uses.

[0039]

As described above, according to the jig of the present invention, the Al ₂ O ₃ content is 99.0% by weight or more and the porosity is 3
Since it is formed from a porous ceramic body having a pore size of 0 to 60% and an average pore diameter of 5 μm or less, it is possible to set each member to be brazed for a long period of time by eliminating cracks due to heat even when used many times, In addition, it is possible to provide a jig in which a substance having a low melting point in the jig is not melted and adhered to each member at the time of brazing, and further, chipping or cracking does not occur during transportation or brazing assembly. .

[Brief description of the drawings]

1A is a perspective view showing a jig of the present invention, and FIG. 1B is a cross-sectional view taken along line AA of FIG.

2A is a perspective view showing an envelope of a current introduction terminal after brazing, and FIG. 2B is a cross-sectional view taken along the line BB of FIG. 2A.

FIG. 3 is a cross-sectional view showing a state in which an enclosure of a current introduction terminal is combined with the jig of the present invention.

FIG. 4 is a perspective view showing another embodiment of the present invention.

FIG. 5 is a plan view showing the semiconductor element housing package after brazing.

6A is a plan view showing a state in which a jig of the present invention is combined with a semiconductor element housing package, and FIG. 6B is a partially enlarged cross-sectional view taken along the line CC of FIG. 6A.

[Explanation of symbols]

 Reference numerals 1 and 21: jig 2: cylindrical portion 3: first flange portion 4: second flange portion 5: flange portion 6: tip member 7: protrusion 8: intermediate member 9: one end portion 10: rear end member 11: cavity 12 : Brazing material 22: Base 23: Frame 24: Concave 25: Base 26: Lead pin

Claims (1)

(57) [Scope of request for utility model registration] 1. A brazing jig made of a porous ceramic body having an Al ₂ O ₃ content of 99.0% by weight or more, a porosity of 30 to 60% , and an average pore diameter of 5 μm or less .