JP7517866B2 - Carbon Composite Materials - Google Patents

Description

The present invention relates to a carbon composite member.

Carbon materials such as graphite are used in many fields, including semiconductor manufacturing, chemical industry, machinery, and atomic energy, due to their excellent chemical stability, heat resistance, and mechanical properties. In addition, graphite itself is porous, and so it is prone to adsorbing gases, moisture, impurities, etc. inside the pores, making the inside of the pores susceptible to contamination. For this reason, a technology is known that reduces the adverse effects of graphite by applying a pyrolytic carbon coating to prevent these contaminants from being re-released from the pores.

Pyrolytic carbon forms a hard, gas-impermeable, dense film that is particularly suitable for use in high purity environments.
For such an application, Patent Document 1 describes a semiconductor manufacturing equipment component that is made of a carbon material, has a pyrolytic carbon layer formed on at least a surface that comes into contact with a raw material gas, and has a wetting tension of 62.0 mN/m or more on the surface that comes into contact with the raw material gas.

JP 2007-12933 A

However, the above-described technology relates to semiconductor manufacturing equipment that processes relatively small wafers, and in order to prevent the adsorption of gas, moisture, and impurities into the interior and the release of these substances, it is necessary to seal support points that are created during coating and to cover the entire surface of the carbon material such as the graphite substrate. In particular, with large-sized carbon composite members, the impact on the pyrolytic carbon coating during handling is large, and it is necessary to prevent peeling.
In view of the above problems, an object of the present invention is to provide a carbon composite member having a strong pyrolytic carbon layer that covers the entire graphite base material.

The carbon composite member according to the present invention, which solves the above problems, is as follows:

(1) A carbon composite member having a plurality of pyrolytic carbon layers formed on a graphite substrate,
A carbon composite member, comprising: a pore region in which pores exist at the boundary between one of said pyrolytic carbon layers and another of said pyrolytic carbon layers adjacent thereto.

According to the carbon composite member of the present invention, the pyrolytic carbon layer is made up of a plurality of layers, and therefore the effect of preventing the adsorption and release of gas, moisture, and impurities from the graphite base material can be enhanced.
On the other hand, the pyrolytic carbon layer is a highly anisotropic material in which graphite crystals extend in the planar direction, and the a-axis direction of the strong graphite extends in the planar direction and is connected in the thickness direction to the c-axis direction of the graphite weakly bonded by van der Waals forces. For this reason, in a pyrolytic carbon layer that is laminated in multiple layers, the boundary between one pyrolytic carbon layer and an adjacent pyrolytic carbon layer is weak and is prone to peeling. On the other hand, in the carbon composite member according to the present invention, the boundary between one pyrolytic carbon layer and another adjacent pyrolytic carbon layer has a pore region in which pores exist, so that the crystal orientation of the pyrolytic carbon is disturbed around the pores, which strengthens the anchor effect and has the effect of preventing interlayer peeling.

In addition, the carbon composite member according to the present invention for solving the above problems preferably has the following features:

(2) When the plurality of pyrolytic carbon layers are designated as a first layer, a second layer, ..., an (n-1)th layer, and an nth layer in order from the side closest to the graphite base material,
the first layer has a first opening, the nth layer has an nth opening,
The carbon composite member according to (1), wherein the first opening and the nth opening are formed at different positions with respect to the graphite substrate.

In a carbon composite member according to a preferred embodiment of the present invention, the first opening in the first layer closest to the graphite substrate and the nth opening in the outermost nth layer are located at different positions relative to the graphite substrate, so that the first opening is blocked, preventing the release of gas, moisture, impurities, etc. from the graphite substrate and preventing the adsorption of gas, moisture, impurities, etc. from the outside.

(3) The carbon composite member described in (2) is characterized in that the second layer covers the first opening, and the pore region at the boundary between the first layer and the second layer around the first opening extends at an angle toward the graphite substrate.

In a carbon composite member according to a preferred embodiment of the present invention, the second layer covers the first opening in the first layer, thereby enhancing the effect of preventing the graphite substrate from emitting gas, moisture, and impurities and from adsorbing them from the outside. In addition, the pore region at the boundary between the first and second layers around the first opening extends at an angle toward the graphite substrate, enhancing the reinforcing effect of the boundary portion of the first opening where stress concentration is likely to occur.

(4) A carbon composite member according to (2) or (3), characterized in that the pore region is present at the boundary between the nth layer and the n-1th layer immediately below the nth layer, and the nth layer is gradually thinner toward the nth opening.

A carbon composite member according to a preferred embodiment of the present invention has the pore region at the boundary between the nth layer and the n-1th layer immediately below the nth layer, and the nth layer becomes gradually thinner toward the nth opening, which can reduce stress concentration and increase the reinforcing effect of the boundary portion of the second opening, which is thinner than other portions.

(5) A carbon composite member according to any one of (1) to (4), characterized in that the pores have a maximum pore diameter of 0.5 to 3.0 μm.

In the carbon composite member according to the preferred embodiment of the present invention, the maximum pore diameter of the pores is 0.5 μm or more, so that the pyrolytic carbon components with different orientation directions formed around the pores can be sufficiently secured, and the anchor effect can be fully exerted by the formation of the pores. In addition, the maximum pore diameter of the pores is 3.0 μm or less, so that the stress concentration around the pores can be reduced, and the reduction in strength due to the presence of the pores can be prevented.

(6) A carbon composite member according to any one of (1) to (5), characterized in that the total thickness of the pyrolytic carbon layers is 5 to 400 μm.

In a carbon composite member according to a preferred embodiment of the present invention, the total thickness of the pyrolytic carbon layers is 5 μm or more, so that the irregularities of the porous graphite substrate can be sufficiently covered and gas impermeability can be ensured. In addition, the total thickness of the pyrolytic carbon layers is 400 μm or less, so that warping and peeling due to thermal distortion of the graphite substrate and pyrolytic carbon layers can be prevented.

(7) A carbon composite member according to any one of (1) to (6), characterized in that the graphite base material is an isotropic graphite material.

In the carbon composite member according to a preferred embodiment of the present invention, the graphite base material is an isotropic graphite material. Since isotropic graphite has small anisotropy and high uniformity in its properties, the difference in the thermal expansion coefficient with the pyrolytic carbon layer is small depending on the location and direction, making it difficult to peel off.

According to the carbon composite member of the present invention, the pyrolytic carbon layer is made up of a plurality of layers, and therefore the effect of preventing the adsorption and release of gas, moisture, and impurities from the graphite base material can be enhanced.
On the other hand, the pyrolytic carbon layer is a highly anisotropic material in which graphite crystals extend in the planar direction, and the a-axis direction of the strong graphite extends in the planar direction and is connected in the thickness direction to the c-axis direction of the graphite weakly bonded by van der Waals forces. For this reason, in a pyrolytic carbon layer that is laminated in multiple layers, the boundary between one pyrolytic carbon layer and an adjacent pyrolytic carbon layer is weak and is prone to peeling. On the other hand, in the carbon composite member according to the present invention, the boundary between one pyrolytic carbon layer and another adjacent pyrolytic carbon layer has a pore region in which pores exist, so that the crystal orientation of the pyrolytic carbon is disturbed around the pores, which strengthens the anchor effect and has the effect of preventing interlayer peeling.

FIG. 1 is an enlarged view of a cross section of a carbon composite member according to a first embodiment of the present invention. FIG. 2 is a diagram showing a manufacturing process of the carbon composite member according to the first embodiment of the present invention. FIG. 3 is a cross-sectional view of a carbon composite member according to a second embodiment of the present invention. FIG. 4 is an enlarged view of a cross section of part A of a carbon composite member according to a second embodiment of the present invention. FIG. 5 is an enlarged view of a cross section of part B of a carbon composite member according to a second embodiment of the present invention. FIG. 6 is a diagram showing a manufacturing process of a carbon composite member according to the second embodiment of the present invention. FIG. 7 is an enlarged view showing the layers formed in steps (C), (D) and (E) in the manufacturing process shown in FIG.

Detailed Description of the Invention
<First embodiment>
First, a description will be given of a first embodiment of the present invention. Fig. 1 is a diagram showing a carbon composite member according to the first embodiment of the present invention, and more specifically, an enlarged view of a cross section near the surface.
A first layer 2A, which is one pyrolytic carbon layer, and a second layer 2B, which is another pyrolytic carbon layer, are laminated on the graphite substrate 1. A large number of pores 3 are formed so as to spread in a layered manner at the boundary between the first layer 2A and the second layer 2B. The region in which the pores 3 exist in a layered manner is a pore region 4.

The pyrolytic carbon layers that become the first layer 2A and the second layer 2B can be formed by a CVD method. In the main part of the pyrolytic carbon layer, the a-axis direction extends along the surface direction of the graphite substrate 1, and the c-axis direction extends along the vertical direction. Therefore, if multiple pyrolytic carbon layers are stacked, peeling is likely to occur at the boundary region where thermal distortion or the like occurs. Therefore, in the carbon composite member according to this embodiment, a pore region 4 containing pores 3 is formed at the boundary between the adjacent first layer 2A and second layer 2B, disrupting the arrangement of the pyrolytic carbon layers and making them less likely to peel off.

Such a pore region 4 can be obtained as follows.
Fig. 2 is a diagram showing a manufacturing process of the carbon composite member shown in Fig. 1. First, a graphite substrate 1 having a desired shape is prepared. When a pyrolytic carbon layer is formed on the graphite substrate 1, the substrate becomes larger by the thickness thereof, so it is preferable to process the substrate smaller according to the size of the carbon composite member and the thickness of the pyrolytic carbon layer to be formed. The surface of the graphite substrate 1 may be roughened to improve adhesion with the pyrolytic carbon layer.

The graphite substrate 1 is then placed in a CVD furnace, and the temperature is raised to the film formation temperature, after which a source gas is introduced. The film formation temperature is not particularly limited, but may be, for example, 800 to 2000° C. The source gas for obtaining the pyrolytic carbon layer is not particularly limited as long as it is a hydrocarbon. For example, source gases such as alkanes, such as methane, ethane, propane, and butane, alkenes, such as ethylene and propylene, and alkynes, such as acetylene, as well as aromatic source gases, such as benzene and toluene, may be used.
Then, the film formation temperature is maintained and the raw material gas is introduced for a certain period of time, thereby forming a pyrolytic carbon layer to become the first layer 2A on the surface of the graphite substrate 1. Note that an inert gas such as Ar can be used as the carrier gas.

Next, when the first layer 2A, which is the pyrolytic carbon layer, reaches a predetermined thickness, a pore region 4 is formed on the surface of the first layer 2A by a method described in detail below. Furthermore, after the pore region 4 is formed, the pyrolytic carbon is kept constant under the CVD conditions for film formation, and another pyrolytic carbon layer, which will become the second layer 2B, is formed continuously on the pyrolytic carbon layer on which the pore region 4 has been formed.

If the pyrolytic carbon layer is in a stable film-formation state, it is formed with uniform directionality, with the a-axis direction extending horizontally (left and right direction in the figure) relative to the graphite substrate 1 and the c-axis direction extending vertically (up and down direction in the figure) relative to the graphite substrate 1, but if the film-formation state is unstable, the source gas is pyrolyzed above the graphite substrate 1, turns into particles, and accumulates on the graphite substrate 1, causing a disorder in the arrangement of the pyrolytic carbon layer. If such a disorder in the arrangement is generated in the main part of the pyrolytic carbon layer, it will cause a decrease in the function of the pyrolytic carbon layer, such as a decrease in airtightness.
However, in the carbon composite member of this embodiment, since the pore region 4 is generated at the boundary between the first layer 2A and the second layer 2B, this does not cause a deterioration in the performance of the carbon composite member, but rather acts to strengthen the bonding strength between the first layer 2A and the second layer 2B, which are multiple pyrolytic carbon layers, making them less likely to peel off.

The pore region 4 can be formed either at the end of the deposition of the first layer 2A or at the start of the deposition of the second layer 2B. For example, when forming the pore region 4 at the start of the deposition of the second layer 2B, an unstable situation is created at the start of the deposition by increasing the partial pressure of the gas or increasing the temperature, particles are generated on the surface of the first layer 2A, and then the pyrolytic carbon layer that will become the second layer 2B is formed under stable conditions. When forming the pore region 4 at the end of the deposition of the first layer 2A, an unstable situation is created at the end of the deposition by increasing the partial pressure of the gas or increasing the temperature, particles are generated, and then the pyrolytic carbon layer that will become the second layer 2B is formed under stable conditions. The particles are scattered and accumulated on the surface of the first layer 2A, so when the pyrolytic carbon layer that will become the second layer 2B is deposited on it, pores 3 are formed around the particles. The pores 3 spread in layers at the boundary between the first layer 2A and the second layer 2B, and become the pore region 4.

One example of the conditions for generating and depositing these pyrolytic carbon particles is a pressure of 10 to 10,000 Pa and a temperature of 800 to 2,000° C. within the CVD furnace.
Furthermore, in order to deposit more pyrolytic carbon particles on the surface of the first layer 2A and form more pores 3, the upper space above the pyrolytic carbon layer in the CVD furnace should be made larger. If the upper space is larger, a larger amount of pyrolytic carbon particles are generated, and more pyrolytic carbon particles can be deposited on the surface of the first layer 2A.

In the above, the pyrolytic carbon layer is shown as a two-layer structure of the first layer 2A and the second layer 2B, but the pyrolytic carbon layer according to this embodiment can be a multi-layer structure of three or more layers. In that case, the pore region 4 can be formed at the start or end of the deposition of each layer in the same manner. Furthermore, when the pyrolytic carbon layer has three or more layers, the effect of the present invention can be achieved as long as the pore region 4 is present at the boundary between at least one pair of adjacent pyrolytic carbon layers. However, in order to fully exert the effect of preventing delamination, it is preferable to have the pore region 4 at all boundaries between a pair of adjacent pyrolytic carbon layers.

The pyrolytic carbon layer can be formed on both sides of the graphite substrate 1. After forming a pyrolytic carbon layer on one surface of the graphite substrate 1, the graphite substrate 1 can be turned over and deposition can be performed with the other surface as the upper surface. Alternatively, the pyrolytic carbon layer can be formed so as to cover the entire surface of the graphite substrate 1. Then, the pore region 4 can be formed in the same manner at the start or end of deposition of each layer.

Next, it is preferable that the maximum pore diameter of the pores 3 is 0.5 to 3.0 μm. By having the maximum pore diameter of the pores 3 be 0.5 μm or more, it is possible to secure a sufficient amount of pyrolytic carbon components with different orientation directions that are formed around the pores 3, and the formation of the pores 3 can fully exert the anchor effect. Furthermore, by having the maximum pore diameter of the pores 3 be 3.0 μm or less, it is possible to reduce stress concentration around the pores 3 and prevent a decrease in strength due to the presence of the pores 3. It is more preferable that the maximum pore diameter of the pores 3 be 1 to 2 μm.

If the pore region 4 is too thick, peeling is likely to occur starting from the pores 3, and if it is too thin, the effect of disturbing the orientation of the pyrolytic carbon is small, and the effect of strengthening the bonding strength between the upper and lower pyrolytic carbon layers is not obtained. Therefore, the thickness of the pore region 4 is preferably 0.5 to 20 μm, and more preferably 1 to 5 μm.

The total thickness of the pyrolytic carbon layers is preferably 5 to 400 μm. When the total thickness of the pyrolytic carbon layers is 5 μm or more, the irregularities of the porous graphite substrate 1 can be sufficiently covered, ensuring gas impermeability. Furthermore, when the total thickness of the pyrolytic carbon layers is 400 μm or less, warping and peeling due to thermal distortion of the graphite substrate 1 and the pyrolytic carbon layers can be prevented. A more preferable total thickness of the pyrolytic carbon layers is 10 to 200 μm.

The thickness of the pyrolytic carbon layer here is the thickness excluding the pore region 4. For example, the thickness of the first layer 2A is the thickness of the first layer 2A formed on the graphite substrate 1, and does not include the thickness of the pyrolytic carbon deposited by changing the deposition conditions to generate particles. The thickness of the second layer 2B is the thickness of the pyrolytic carbon layer when deposited after particles are generated.

The graphite material that will become the graphite substrate 1 is preferably an isotropic graphite material. Since isotropic graphite has small anisotropy and high uniformity in its properties, the difference in thermal expansion coefficient between the pyrolytic carbon layer and the substrate is small depending on the location and direction, making it difficult to peel off.

<Embodiment 2>
Next, a description will be given of a second embodiment of the present invention. Fig. 3 is a cross-sectional view of a carbon composite member according to the second embodiment of the present invention.

A carbon composite member having the configuration shown in FIG. 3, that is, a configuration in which multiple pyrolytic carbon layers are formed over the entire surface of the graphite substrate 1, can be manufactured, for example, by a manufacturing method using a predetermined support as shown in FIG. 1 of JP 2016-169422 A (the details of this manufacturing method will be described later). In this case, a first opening 10 and a second opening 11 are formed in part of the pyrolytic carbon layer.

As shown in FIG. 3, in the carbon composite member according to this embodiment, the graphite substrate 1 is covered with the first layer 2A and the second layer 2B, and the first layer 2A has a first opening 10 (two openings in FIG. 3) on one side (top side in FIG. 3) of the graphite substrate 1, and the second layer 2B covers the first opening 10. Therefore, the airtightness from the first opening 10 to the graphite substrate 1 is ensured by the second layer 2B. On the other hand, the other side (bottom side in FIG. 3) of the graphite substrate 1 does not have the first opening 10, is entirely covered by the first layer 2A, and has the second opening 11 (two openings in FIG. 3) in the second layer 2B. Therefore, the airtightness from the second opening 11 to the graphite substrate 1 is ensured by the first layer 2A.

That is, the first opening 10 in the first layer 2A closer to the graphite substrate and the second opening 11 in the outer second layer 2B are located at different positions relative to the graphite substrate 1, so that the first opening 10 is blocked, preventing the release of gas, moisture, impurities, etc. from the graphite substrate 1 and preventing the adsorption of gas, moisture, impurities, etc. from the outside. The first opening 10 and the second opening 11 may be formed in one place in each of the first layer 2A and the second layer 2B, or in multiple places.

In FIG. 3, the case of two layers, a first layer 2A and a second layer 2B, is described as the multiple pyrolytic carbon layers. However, for example, if the multiple pyrolytic carbon layers are the first layer, the second layer, ..., the n-1th layer, and the nth layer in order from the side closest to the graphite substrate 1, and the first layer has the first opening and the nth layer has the nth opening, and the first opening and the nth opening are formed at different positions relative to the graphite substrate 1, the same effect as above can be achieved. Here, n is an integer of 2 or more.

Figure 4 is an enlarged cross-sectional view of part A in Figure 3, showing in detail the periphery of the first opening 10 formed in the first layer 2A (area C in the figure).

As shown in FIG. 4, the second layer 2B covers the first opening 10, and the pore region 4 at the boundary between the first layer 2A and the second layer 2B in the periphery of the first opening (region C) extends at an incline toward the graphite substrate 1. That is, since the second layer 2B covers the first opening 10 in the first layer 2A, the effect of preventing the graphite substrate 1 from emitting gas, moisture, and impurities and from adsorbing them from the outside can be enhanced. In addition, since the pore region 4 at the boundary between the first layer 2A and the second layer 2B in the periphery of the first opening (region C) extends at an incline toward the graphite substrate 1, the reinforcing effect of the boundary portion of the first opening 10 where stress concentration is likely to occur can be enhanced.

Figure 5 is an enlarged cross-sectional view of part B in Figure 3, showing in detail the periphery (area D) of the second opening 11 formed in the second layer 2B.

As shown in FIG. 5, the first layer 2A has no openings, and the second layer 2B is formed by laminating it on the upper surface of the first layer 2A (the lower side in the figure), with the second layer 2B having a second opening 11. The second layer 2B has a pore region 4 at the boundary between the first layer 2A and the second layer 2B directly below it, and as shown by region D in the figure, the second layer 2B gradually becomes thinner toward the second opening 11, which can alleviate stress concentration and enhance the reinforcing effect of the boundary portion of the second opening, which is thinner than other portions.

In FIG. 5, the case where the multiple pyrolytic carbon layers are two layers, a first layer 2A and a second layer 2B, is described, but as in the case described in FIG. 3, if there is a pore region 4 at the boundary between the nth layer and the n-1th layer immediately below the nth layer, and the nth layer becomes gradually thinner toward the nth opening, the same effect as above can be achieved. Note that n is an integer of 2 or more.

Next, a detailed description will be given of a method for manufacturing a carbon composite member according to the second embodiment of the present invention. To manufacture such a carbon composite member, for example, the steps shown in FIG.
In the figure, (A) shows the graphite substrate 1, (B) shows the process of forming the first layer 2A, (C) shows the process of forming the pore regions 4 on the first surface 1a side of the graphite substrate 1, (D) shows the process of forming the pore regions 4 on the second surface 1b side of the graphite substrate 1 (i.e., the side where the first openings 10 are formed), and (E) shows the process of forming the second layer 2B. As shown in the figure (A), one surface (upper surface in the figure) of the graphite substrate 1 is the first surface 1a, and the other surface (lower surface in the figure) is the second surface 1b. In addition, Fig. 7 shows an enlarged view of each layer formed in the steps (C), (D), and (E) of Fig. 6.

First, as shown in step (B), the graphite substrate 1 is placed on the support 20. The support 20 is placed on a substrate holder (not shown) of a CVD device. The support 20 has, for example, a cylindrical support body 21 and a support part 22 protruding from the center of the support body 21, and is formed integrally. To integrate these, for example, the support body 21 and the support part 22 can be processed to obtain them, or the support body 21 and the support part 22 can be bonded together with an adhesive or the like.

The support part 22 has a truncated cone shape as a whole, and in a cross section along the axis, it has a shape with an inclined surface that gradually expands in diameter from the top surface 23 toward the support body 21. The top surface 23 can be flat as shown in the figure, or it can be a pointed shape (cone shape). The second surface 1b of the graphite base material 1 is in contact with and supported by this support part 22.

In this state, a stable CVD method is performed to form a pyrolytic carbon layer. As a result, as shown in the figure, a first layer 2A is formed to cover the graphite substrate 1 except for the periphery of the support portion 22 of the support 20. At that time, a first opening 10 is formed in the first layer 2A in a shape that conforms to the outer shape of the support portion 22.

Next, as shown in step (C), unstable CVD is performed to sufficiently form pore regions 4 over the entire surface of the first surface 1a of the graphite substrate 1 of the first layer 2A. Note that it is believed that pore regions 4 are also formed to some extent on the second surface 1b of the graphite substrate 1, but the amount is smaller than that on the first surface 1a of the graphite substrate 1.

Next, as shown in step (D), the graphite substrate 1 is turned over (upside down) and the first surface 1a is placed on the support 20. Accordingly, the first opening 10 of the first layer 2A faces upward in the figure. Then, unstable CVD is performed again to sufficiently form the pore region 4 over the entire surface on the second surface 1b side of the graphite substrate 1 (i.e., the side on which the first opening 10 is formed). At that time, the pyrolytic carbon particles also fall and accumulate on the first opening 10, so that the pore region 4 is also formed on the first opening 10 (see FIG. 4).

Next, as shown in step (E), stable CVD is performed to form the second layer 2B. Through the above steps, the first opening 10 is blocked by the second layer 2B, as shown in FIG. 4, and a pore region 4 is also formed in the second opening 11, as shown in FIG. 5. That is, according to the above manufacturing method, a carbon composite member can be manufactured in which the second layer 2B covers the first opening 10, the pore region 4 at the boundary between the first layer 2A and the second layer 2B around the first opening (area C) extends at an angle toward the graphite substrate 1, and the second layer 2B gradually becomes thinner toward the second opening 11.

As described above, the first layer 2A and the second layer 2B are formed using the support 20, for example, a cylindrical support body 21 and a truncated cone-shaped support part 22 protruding from the center of the support body 21. Therefore, at the openings of each layer (first opening 10, second opening 11), a pyrolytic carbon layer that gradually becomes thinner toward each opening can be formed.

The present invention has been described above using the first and second embodiments, but it is not limited to these embodiments and can be modified, improved, changed, etc. as appropriate.

The carbon composite member of the present invention has higher overall performance due to the graphite base material being covered with multiple pyrolytic carbon layers, and also has excellent durability as it prevents the pyrolytic carbon layers from peeling off from each other. Therefore, it is effective in many fields such as semiconductor manufacturing, chemical industry, machinery, and atomic energy.

1 Graphite substrate 2A First layer (first pyrolytic carbon layer)
2B 2nd layer (another pyrolytic carbon layer)
3: pore 4: pore region 10: first opening 11: second opening 20: support 21: support body 22: support portion 23: top surface

Claims (6)

A carbon composite member having a plurality of pyrolytic carbon layers formed on a graphite substrate,
a pore region in which pores exist at a boundary between one of the pyrolytic carbon layers and another of the pyrolytic carbon layers adjacent thereto ;
A carbon composite member, characterized in that the thickness of the pore region is 0.5 to 20 μm, and the total thickness of the pyrolytic carbon layer is 5 to 400 μm . When the plurality of pyrolytic carbon layers are designated as a first layer, a second layer, ..., an (n-1)th layer, and an nth layer in order from the side closest to the graphite base material,
the first layer has a first opening, the nth layer has an nth opening,
The carbon composite member according to claim 1 , wherein the first opening and the nth opening are formed at different positions with respect to the graphite substrate. The carbon composite member according to claim 2, characterized in that the second layer covers the first opening, and the pore region at the boundary between the first layer and the second layer around the first opening extends at an angle toward the graphite substrate. The carbon composite member according to claim 2 or 3, characterized in that the pore region is present at the boundary between the nth layer and the n-1th layer immediately below the nth layer, and the nth layer is gradually thinner toward the nth opening. The carbon composite member according to any one of claims 1 to 4, characterized in that the pores have a maximum pore diameter of 0.5 to 3.0 μm. The carbon composite member according to any one of claims 1 to 5 , characterized in that the graphite base material is an isotropic graphite material.

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