JPH06268117A - Heat radiating substrate for semiconductor device and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a heat radiating substrate for semiconductor devices which has excellent thermal conductivity, a high quality, high reliability, and a coefficient of thermal expansion well matching to those of a semiconductor chip and package constituting material. CONSTITUTION:The title heat radiating substrate 10 is composed of a base material 1 and sandwich materials 2a and 2b stuck to both surfaces of the base material 1. The base material 1 is composed of at least one kind of metallic material selected out of W-Cu and Mo-Cu. The sandwich materials 2a and 2b are composed of a metallic material containing Cu as a main constituent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat dissipation substrate for a semiconductor device and a method of manufacturing the same, and more particularly to a lightweight and highly reliable clad type heat dissipation substrate for a semiconductor device used in LSIs, ICs, power transistors and the like. The present invention relates to a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, as a heat dissipation substrate for a semiconductor device,
Cu (copper), W (tungsten), Mo (molybdenum), W-Cu, Mo-C as shown in Table 1 below.
u, Cu / Mo / Cu (hereinafter referred to as CMC) have been used. These have respective advantages and disadvantages as shown in the same table, and are used for applications corresponding to them.

[0003]

[Table 1]

[0004]

As is clear from Table 1 above, it has basic characteristics such as high thermal conductivity and a small difference in thermal expansion coefficient between the semiconductor element and the package surrounding base material. Conventionally, a heat dissipation board for a semiconductor device that meets all the requirements of low cost and light weight has not been obtained.

Referring to Table 1 above, for example, Cu is excellent in thermal conductivity, but Si (silicon), GaAs (gallium arsenide) of the semiconductor element and the surrounding base material Al ₂ O _{3 are used.}
The difference in the coefficient of thermal expansion with (alumina) is large. therefore,
This Cu is a small IC with a small amount of heat dissipation, and can be used only for soft solder such as low melting point solder.

Further, although W and Mo have a thermal expansion coefficient close to that of Si of a semiconductor element, they are not so excellent in thermal conductivity. Therefore, W and Mo are used only for a large IC that can form a wide heat dissipation surface as a substrate on which Si is mounted.

Therefore, W-Cu and Mo-Cu composite alloys and clad type C.I. M. C. Was developed,
It is used for medium- or large-sized ICs.

Among these, W, Mo and W-Cu and Mo-Cu containing a large amount thereof are high in weight and are not suitable for the demand for weight reduction. Also, because they have rigidity,
Plastic working is difficult.

On the other hand, Cu and C.I. M. C. Can be plastically processed due to the ductility of Cu. Since Cu has a large difference in coefficient of thermal expansion from the semiconductor element and ceramic as described above, defects are likely to occur at the joint interface with the mating material due to the effects of thermal stress during assembly and operation, and The substrate itself is also susceptible to deformation, cracks and other damage.

C. M. C. In consideration of the above-mentioned points, while reducing the amount of Mo while utilizing the characteristics of Mo, C
By increasing the amount of u, the weight can be reduced and C
It is attracting attention as a material that makes full use of the ductility of u to facilitate processing. In addition, C.I. M. C. Has an advantage that the thermal conductivity and the thermal expansion coefficient can be freely changed by changing the thickness ratio of Mo of the base material and Cu of the laminated material.

However, C.I. M. C. Has the following drawbacks. FIG. 3 shows C.I. M. C. To explain the drawbacks of C. M. C. FIG. With reference to FIG. M. C. Is clad by rolling, the Cu layer 102a, due to the difference in ductility between Mo and Cu,
The thickness of the Mo layer 101 sandwiched between the layers 102b is not uniform in the X and Y directions (length and width directions) and becomes wavy. Therefore, the thickness (t ₁ , t ₂ ) of the Mo layer 101 is different in each part. Therefore, the coefficient of thermal expansion in the Z direction (thickness direction) is different in each part, and the substrate 110 itself is likely to be twisted. Therefore, C.I. M. C. Has a problem that it cannot be used for an IC having a high capacity and a large heat radiation amount.

Further, C.I. M. C. Then, although the thermal conductivity in the X and Y directions is significantly improved by forming the cladding, there is also a problem that the thermal conductivity in the Z direction is deteriorated because the Mo layer 101 is provided in the middle.

The present invention has been made in order to solve the above-mentioned problems, and has excellent thermal conductivity, good thermal expansion matching with semiconductor elements and package components, and high thermal conductivity. An object of the present invention is to provide a high quality and highly reliable heat dissipation board for a semiconductor device and a method for manufacturing the same.

[0014]

The heat dissipation substrate for a semiconductor device of the present invention has been made based on the following knowledge.

That is, the present inventors have conducted extensive studies to solve the above-mentioned problems, and as a result, W-Cu or Mo-C
The heat dissipation substrate for semiconductor devices, in which Cu is clad bonded as the bonding material on both upper and lower sides of the base material of u composite alloy, has excellent thermal conductivity, has a small difference in coefficient of thermal expansion from semiconductor elements, and is lightweight and excellent in workability. In addition, they have found that the substrate has small waviness and good thermal conductivity in the thickness direction.

Therefore, the heat dissipation substrate for a semiconductor device of the present invention is a heat dissipation substrate for a semiconductor device for mounting or holding a semiconductor element, and has one and the other main surfaces facing each other and is made of tungsten. A first member made of at least one metal material selected from the group consisting of copper alloys and molybdenum-copper alloys, and one main surface of one and the other of the first members are joined to each other, and copper is the main material. And a second member made of a metal material.

The heat dissipation substrate for a semiconductor device of the present invention uses, as a base material, at least one metal material selected from the group consisting of W-Cu and Mo-Cu. Therefore, the thermal conductivity and thermal expansion coefficient of the clad material are W-Cu,
It can be controlled by the thickness ratio of the Mo-Cu layer and the Cu layer. This point is C.I. M. C. Is the same as
In the heat dissipation substrate for semiconductor device of the present invention, W-Cu,
By controlling the amount of Cu in the Mo-Cu layer, the thermal conductivity and the thermal expansion coefficient can be controlled more precisely.

In the heat dissipation board for semiconductor device of the present invention,
A metallic material containing Cu as a main material is bonded to both surfaces of the base material. Therefore, regarding the ease of plating, the ease of press working, the improvement of the processing surface accuracy, and the weight reduction by using Cu on both sides, C.I. M. C. The same effect as can be obtained. In addition, in the heat dissipation board for semiconductor devices of the present invention, C.I. M. C. Even if the same base material, the same laminated material, and the same thickness ratio as C. M. C. Excellent thermal conductivity can be obtained as compared with.

C. M. C. Then, since the bondability between Mo and Cu and the plastic workability of Mo itself are poor, high pressure is required during rolling. Since rolling is performed under high pressure,
C. M. C. In this case, the Mo layer is corrugated or cracked, and strain is likely to occur at the bonding interface due to the difference in thermal expansion coefficient, and strain of the material is also likely to occur. In addition, C.I. M. C. Then
The difference in thermal expansion in the Z direction becomes larger than that in the X and Y directions. That is, the coefficient of thermal expansion in the Z direction is significantly lower than the coefficient of thermal expansion of the semiconductor element or the package constituent material. From the above, C.I. M. C. Then, there is a tendency to thin the Mo layer, but when the Mo layer is made too thin, the problem of waviness and cracking of the Mo layer becomes more remarkable as the thickness is made thinner.

On the other hand, in the heat dissipation substrate for a semiconductor device of the present invention, since at least one metal material selected from the group consisting of W-Cu and Mo-Cu is used as a base material, Cu as a composite material is used. Joining becomes easier and the workability is also improved.

Further, in the heat dissipation board for semiconductor device of the present invention, as a result of the experiment, the corrugation of the base material is ± in the thickness direction.
The content was within 3%, the semiconductor element and the like were joined with high precision, and no defect was observed at the interface. It is considered that the joining with high precision as described above has been effective in achieving high thermal conductivity and a desired coefficient of thermal expansion as shown in the examples.

Further, as a result of experiments, it was found that the heat dissipation substrate for a semiconductor device of the present invention is also excellent in thermal conductivity in the Z direction. Therefore, in an IC with high heat generation, a fin is provided on the back surface of the semiconductor substrate to increase the radiation area. However, since the heat dissipation in the Z direction is improved by W-Cu and Mo-Cu,
More efficient ones can be obtained.

In the heat dissipation substrate for semiconductor device of the present invention, it is preferable that the semiconductor material forming the semiconductor element contains either silicon or gallium arsenide.

In the heat dissipation substrate for a semiconductor device of the present invention, an insulating thin layer made of a ceramic or an organic material having a material and thickness suitable for the application is formed on the surface thereof by various plating methods, vapor deposition methods, dipping methods, coating methods and the like. Can also be formed. By forming an insulating thin layer on the surface in this manner, the heat dissipation substrate for a semiconductor device of the present invention can be used for applications requiring electrical insulation, and can be replaced with a conventional ceramic or organic insulating substrate. It is also possible to use.

The heat dissipation substrate for a semiconductor device of the present invention is WC
It is manufactured by arranging Cu as a bonding material on both upper and lower surfaces of a base material of u or Mo-Cu, rolling it, or laminating it and then hot uniaxially processing it.

Therefore, a method of manufacturing a heat dissipation board for a semiconductor device according to the present invention is a method of manufacturing a heat dissipation board for a semiconductor device for mounting or holding a semiconductor element, and is made of a tungsten-copper alloy and a molybdenum-copper alloy. A first member made of at least one metal material selected from the group consisting of a second member made of a metal material containing copper as a main material is formed on the one and the other main surfaces of the first member facing each other by the hot uniaxial working method or It has a step of joining by any of the rolling methods.

The method of manufacturing the heat dissipation substrate for a semiconductor device according to the present invention will be described in detail in the case of bonding by rolling.

First, excess Cu and stains on the surfaces of W-Cu and Mo-Cu alloys are removed to prepare a base material having a predetermined thickness. Cu is superposed on both sides of a base material made of this alloy as a bonding material, heated in a non-oxidizing atmosphere, directly introduced from a heating furnace into a rolling mill, bonded, and reduced in thickness. Further, the same heating and rolling are repeated to gradually reduce the thickness and finish it to a desired thickness.

The initial thicknesses of the W-Cu, Mo-Cu alloy and Cu are adjusted according to the required characteristics. However, when the Cu layer and the Mo layer are extremely thick or extremely thin, Cu, Ag (silver), A, etc. are previously prepared by a method such as a plating method, a vapor deposition method, and a (molten metal) dipping method.
By thinly coating a metal of l (aluminum) or Ni (nickel) or a metal thereof, reliable joining can be performed with a small rolling rate. In addition, the thickness of this coating layer does not deteriorate the thermal conductivity, so 3
μm or less is preferable.

The heat treatment temperature is W--Cu or Mo.
Although it depends on the Cu amount of —Cu, 1100 ° C. to 1300 ° C. is preferable, and the heating time is at least 6 for uniformly heating.
0 minutes is required. The atmosphere in that case is a non-oxidizing gas such as H ₂ (hydrogen) or Ar (argon) or 1
The vacuum atmosphere is set to 0 ⁻¹ Torr or less. A particularly preferred atmosphere is H ₂ .

The initial surface roughness Rmax of the W-Cu and Mo-Cu clad surfaces is about 5 μm.
Thereby, the adhesiveness at the time of rolling can be secured.

Further, the Cu, W-Cu, and Mo-Cu clad surfaces are plated with Ni to a thickness of 1 to 3 μm.
Wash to remove dirt, stack immediately and heat.

Regarding the hot rolling condition, the rolling ratio is 5 to 1
It is set to 5% and the joining is completed in 1 to 3 steps. For applications where the surface after rolling is rough and cannot be used, correction cold rolling is further performed to finish the surface so as to have a desired surface roughness.

The rolled hoop is pressed into a predetermined shape to form a substrate. Next, a case where hot uniaxial processing is used in the method for manufacturing a semiconductor device heat dissipation substrate of the present invention will be described in detail.

This hot uniaxial working method is more expensive than the hot rolling method depending on the production method, but the WC of the base material is used.
It is advantageous in that the waviness of u and Mo-Cu can be almost eliminated, and a base material having a stable thickness close to that of the raw material can be obtained.

In this case, a carbon mortar and pestle are used, and a laminated unit of, for example, Cu, W--Cu, Cu is heated in the mortar with a separating agent such as BN or Al ₂ O ₃ interposed therebetween, and then heated. Pressurize for a predetermined time.

To make it cheap, consider serialization.
In this way, it can be manufactured at a low cost comparable to the rolling method.
It is possible enough. Atmosphere during hot uniaxial machining
Is 10 to prevent oxidation.^-1Vacuum below Torr
Under or non-oxidizing gas Ar, N ₂(Nitrogen), He (F
), CO, or a mixed gas thereof.

The temperature is set to 300 ° C. to 850 ° C., and is adjusted according to the amount of Cu in the base material. If the temperature is less than 300 ° C., the diffusion of the metal components in the joint is insufficient and the joint strength cannot be obtained.
If the temperature exceeds ℃, it is difficult to secure dimensional accuracy due to roughened Cu surface, which is not preferable.

The applied pressure is 300 to 1000 kg / cm.
^Set to ² . If the pressure is less than 300 kg / cm ² , bonding strength may not be obtained, or long-term pressurization may be required, and 1000 k
When it exceeds g / cm ² , the Cu portion is deformed and the life of the mold is shortened, which is not preferable.

The pressurizing time is 10 minutes to 3 hours. 1
If it is less than 0 minutes, sufficient strength cannot be obtained, and if it exceeds 3 hours, the effect of pressurization cannot be further obtained.

Regarding the joint strength, JIS Z of the joint portion is used.
-3192 as a shear strength of at least 5 kgf /
mm ² or more is required.

In the method of manufacturing a heat dissipation substrate for a semiconductor device of the present invention, the first member made of at least one metal material selected from the group consisting of W-Cu and Mo-Cu is the infiltration method or the sintering method. It is preferably formed by any of the above.

Hereinafter, in a preferable aspect of the method for manufacturing a heat dissipation substrate for a semiconductor device of the present invention, W-Cu and Mo-Cu are used.
The case of forming by the infiltration method will be described in detail.

First, if necessary, a small amount of powder of Fe (iron), Ni, Co (cobalt) or the like is added to W and Mo powders whose particle sizes have been adjusted in advance, and then mixed and molded. Then, this molded body is heated to 1000 to 1400 ° C. in a non-oxidizing gas atmosphere.
Sintering is carried out at the temperature of to make a porous body composed of W and Mo. The raw materials W and Mo improve the filling property by combining coarse particles and fine particles. The binder used for molding is a low temperature volatile binder that does not leave ash. Furthermore, it is necessary to obtain a porous body having no pores inside the skeleton by using a high-purity gas (preferably H ₂ ) for sintering.

Further, Fe, Ni and Co are melted at the time of forming the skeleton of W and Mo to accelerate the sintering. This Fe, Ni, C
o is 0.2 to 3 wt. % Is preferably added. 0.
2 wt. %, There is no accelerating effect and 3 wt. If it exceeds%, the thermal conductivity will drop sharply.

The sintered porous body was heated to 1100 to 1400 ° C. in a high purity non-oxidizing gas atmosphere (H ₂ is preferable).
The molten Cu is brought into contact with Cu at the temperature of 1 to fill the voids with no gaps to produce a material having a substantial density of 100%. Inside the skeleton and C
u After clad by not forming holes in the filling part,
-Since the Cu layer does not have minute holes, the coefficient of thermal expansion and thermal conductivity of the W-Cu layer can be predicted by the complex rule, making it easy to select a material having a composition according to requirements and high. A thermally conductive substrate can be formed.

Next, in a preferable aspect of the method for manufacturing a heat dissipation substrate for a semiconductor device of the present invention, W-Cu and Mo-Cu are used.
The case of forming by a sintering method will be described in detail.

First, either powder of W or Mo corresponding to the final composition and powder of Cu are mixed and molded. After that, the molded body is sintered in a non-oxidizing atmosphere, and a composite alloy is produced by a method of sintering W and Mo and filling the voids with molten Cu.

The particle size control of the raw materials, Fe, Ni, Co
The contents of addition of a small amount of, the selection of the binder for molding, and the conditions of sintering are in accordance with the above infiltration method.

In this method, the skeleton of W is not formed unlike in the infiltration method and minute voids remain in the Cu portion, so that the infiltration method cannot be 100% dense. Therefore, the same C
Compared with the amount of u, the one formed by the sintering method has a lower thermal conductivity and a higher thermal expansion coefficient than the infiltration method. However, by using the sintering method as compared with the infiltration method, the heating process is shortened and the manufacturing cost can be reduced accordingly. Also in this case, the residual holes are crushed during the clad rolling.

It should be noted that which of the infiltration method and the sintering method should be selected as a method for producing W-Cu or Mo-Cu may be selected depending on the application.

If necessary, W-Cu, Mo-C
Prior to the clad formation of u and Cu, any one of Cu, Ag, Al and Ni or their alloys is formed on the clad interface by a plating method, a vapor deposition method, an immersion method, a coating method, a method of interposing a thin plate or a powder. It is preferable to add. The cladding bondability can be improved by adding these alloys. However, since the alloy layer is formed between the bonding layer and these added metals, the thermal conductivity in the Z direction is slightly reduced. In this case, the final thickness of the applied layer is 3μ
It is preferably m or less.

The present invention will be described below with reference to examples.

[0054]

EXAMPLES Example 1. W powder or Mo powder and Cu powder with Ni powder 1.0 wt. %, 100 mm x 50
The die was embossed into a size of mm × 0.5 to 1.5 mmt. After that, sintering was performed at 1000 to 1400 ° C. in a H ₂ gas atmosphere to make a skeleton. 1100 for this skeleton
Heat at ~ 1400 ° C under H ₂ gas atmosphere to remove Cu from 1
~ 50 wt. % W-Cu or Mo-Cu alloy was produced.

Excess Cu and dirt on the surface of this alloy are removed by washing, and the dimensions are 100 mm × 50 mm × 0.5-
The surface roughness Rmax was set to 1.5 μm and the surface roughness Rmax was set to 4 μm, and then the surface was plated with Ni to a film thickness of 2 μm. Cu was superposed on the upper and lower surfaces of the alloy thus obtained,
It was Cu / W-Cu / Cu or Cu / Mo-Cu / Cu.

The laminated three-layer plate was heated in a hydrogen atmosphere at a temperature of 1130 ° C. for 80 minutes. Then, it was passed directly from the heating furnace to rolling, and hot rolling was performed at a rolling rate of 10% to bond the layers. By repeating the same heat treatment and rolling, the product is reduced in thickness and punched,
A sample having a predetermined thickness was prepared.

Example 2. Ni powder 1.0 wt. %, Φ425mm × 0.7mmt
Stamped to the size of. After that, 1000-1400 ° C
A skeleton was prepared by sintering in a H ₂ gas atmosphere.
This skeleton was heated at 1100 to 1400 ° C. under a H ₂ gas atmosphere, and Cu was added at 10 wt. % W-Cu
Made alloy.

Excess Cu and stains on the surface of this alloy were removed by washing to make the size φ425 mm × 0.7 mmt and the surface roughness Rmax to 4 μm, and then 2 μm on the surface.
Ni plating was performed with a film thickness of. Cu of the same size was superposed on the upper and lower surfaces of the alloy thus obtained, and Cu / W
-Cu / Cu.

This laminated three-layer plate is made of carbon.
Put in a die and pestle, vacuum degree 5 × 10 with hot uniaxial machining equipment^-2
Set to Torr and heat to 500 ° C in a furnace, 500 kg /
cm ²After pressurizing with pressure of 2 hours and holding for 2 hours, prepare a sample
did.

Example 1 above. And Example 2. The results of measuring the thermal conductivity and the coefficient of thermal expansion of the sample obtained by are shown in Table 2 below.

Further, the sample No. of the example of the present invention shown in Table 2 was obtained. 3 and the sample No. of the comparative example. Table 3 shows the actual measurement data of the thermal conductivity in the X, Y, and Z directions for Sample No. 1.

[0062]

[Table 2]

[0063]

[Table 3]

From Tables 2 and 3, the samples of the examples of the present invention have a thermal conductivity of C.I. M. C. Better than C. and C.I.
M. C. It was found that the heat conductivity in the Z direction was less deteriorated than that of No. 1, and the material was remarkably excellent.

Next, the structure and application of the heat dissipation substrate for semiconductor device of the present invention will be described.

FIG. 1 is a perspective view schematically showing the structure of a heat dissipation board for a semiconductor device according to an embodiment of the present invention. Referring to FIG. 1, a heat dissipation substrate 10 for a semiconductor device according to an embodiment of the present invention has a structure in which mating materials 2a and 2b are bonded to both upper and lower surfaces of a base material 1. The base material 1 is made of at least one metal material selected from the group consisting of W-Cu and Mo-Cu. The mating materials 2a and 2b are made of a metal material mainly made of copper. Also the base material 1
The joining materials 2a and 2b are joined by either a hot rolling method or a hot uniaxial working method.

FIG. 2 is a sectional view schematically showing the structure of a semiconductor device using a heat dissipation substrate for a semiconductor device according to an embodiment of the present invention. Referring to FIG. 2, the semiconductor device includes a semiconductor device heat dissipation substrate 10 and a Si semiconductor element IC chip 2
0, an Al ₂ O ₃ surrounding base material 30, a cap 40, and a pin terminal 50. Heat dissipation board 10 for semiconductor device
Has a configuration substantially similar to that shown in FIG.
Further, an Si semiconductor element IC chip 20 and an Al ₂ O ₃ envelope base material 30 are attached to the heat dissipation substrate 10 for semiconductor device. A plurality of pin terminals 50 are provided on the Al ₂ O ₃ envelope base material, and each of the pin terminals 50 is electrically connected to the Si semiconductor element IC chip 20 by a lead wire 60 by wire bonding. ing.
Further, the heat dissipation substrate 10 for semiconductor device of the Al ₂ O ₃ surrounding base material 30 is provided so that the Si semiconductor element IC chip 20 is not exposed.
A cap 40 is attached to the surface side facing the.

The external dimensions of the heat dissipation board 10 for a semiconductor device are 38 m.
m □, Al ₂ O ₃ envelope base material 30 has an outer size of 40 mm □, S
The outer size of the i semiconductor element IC chip 20 is 15 mm □. In this case, the joint length of one side of the Al ₂ O ₃ surrounding base material 30 and the semiconductor device heat dissipation substrate 10 is the outer dimension of the semiconductor device heat dissipation substrate 10 of 38 mm.

In the semiconductor device shown in FIG. 3, sample Nos. 2 attached, -65 ℃ ~ +150
A heat cycle test at ℃ was performed. As a result, H after the test
e Leak amount in the leak test is 10 ^-8 atm · cc / se
No defects such as cracking, cracking, and deformation were observed at the interface of the clad and at the bonding interface with the semiconductor element and other constituent materials.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing a structure of a heat dissipation board for a semiconductor device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view schematically showing a configuration of a semiconductor device using a heat dissipation substrate for a semiconductor device according to an embodiment of the present invention.

FIG. 3 C. M. C. C. showing that the Mo layer had an uneven thickness. M. C. It is sectional drawing which shows the structure of.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base material 2a, 2b Composite material 10 Heat dissipation board for semiconductor device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshiyuki Sakagami 1-1-1 Kunyokita, Itami City, Hyogo Prefecture Sumitomo Electric Industries, Ltd. Itami Works

Claims (4)

[Claims] 1. A heat dissipation substrate for a semiconductor device for mounting or holding a semiconductor element, comprising: a group consisting of a tungsten-copper alloy and a molybdenum-copper alloy, having one and the other main surfaces facing each other. A first member made of at least one selected metal material; and a second member made of a metal material containing copper as a main material, which is joined to one and the other main surfaces of the first member. Also, a heat dissipation board for semiconductor devices. 2. The heat dissipation substrate for a semiconductor device according to claim 1, wherein the semiconductor material forming the semiconductor element contains one of silicon and gallium arsenide. 3. A method of manufacturing a heat dissipation board for a semiconductor device for mounting or holding a semiconductor element, comprising a metal material of at least one selected from the group consisting of a tungsten-copper alloy and a molybdenum-copper alloy. A heat dissipation board for a semiconductor device in which a second member made of a metal material containing copper as a main material is bonded to one and the other of the main surfaces of the first member facing each other by either a hot uniaxial working method or a rolling method. Manufacturing method. 4. The method of manufacturing a heat dissipation board for a semiconductor device according to claim 3, wherein the first member is formed by either an infiltration method or a sintering method.