Silicon component, and method for manufacturing a silicon component.

Abstract

The present invention provides a silicon component that has sufficiently high bonding strength, excellent heat resistance, and can be used stably even in high-temperature environments, as well as a method for manufacturing the silicon component. [Solution] A silicon member 10 is formed by joining a plurality of plate-shaped members 11, 12 made of a Si-containing material in the thickness direction, characterized in that the area ratio of the Si phase in the bonding layer 20 formed between the plate-shaped members 11, 12 is 12% or less, and the bonding layer is made of metal. Preferably, the aspect ratio of the Si phase in the bonding layer 20 is 3.0 or less.

Description

Technical Field

[0005] , , , , ,

[0001] The present invention relates to, for example, a silicon member used in a plasma processing apparatus and a method for manufacturing the silicon member.

Background Art

[0002] Conventionally, in plasma processing apparatuses such as plasma etching apparatuses and plasma CVD apparatuses used in semiconductor device manufacturing processes, for example, an electrode plate connected to a high-frequency power source and a pedestal are arranged to face each other vertically in the chambers of various apparatuses, and a silicon wafer is placed on the pedestal. While flowing gas from through-holes formed in the electrode plate toward the silicon wafer, a high-frequency voltage is applied to generate plasma, and a process such as etching is performed on the silicon wafer.

[0003] In the above-described plasma processing apparatuses and the like, silicon members such as silicon, silicon nitride, and silicon carbide are widely used in order to suppress metal contamination in the chamber. For example, as an electrode plate used in a plasma processing apparatus, a silicon member having a structure in which a plurality of ventilation holes are formed in a silicon plate material is used.

[0004] The silicon member disposed in the chamber of a plasma processing apparatus or the like gradually wears out during use. Therefore, it is required to join another silicon member to the worn silicon member and reuse the obtained silicon joined body as a silicon member. For example, Patent Document 1 discloses a silicon electrode plate in which a plurality of plate-like electrode members made of silicon are joined in the thickness direction.

[0005] In this Patent Document 1, an Al foil is sandwiched between the plate-like electrode members, and heat treatment is performed at 800°C to form a joint portion made of an Al—Si eutectic alloy, and the plate-like electrode members are joined together (see paragraph numbers 0018 - 0026 of Cited Document 1).

Prior Art Documents

[0006] [Patent Document 1] Patent No. 6146840 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] Incidentally, in the silicon electrode plate described in Patent Document 1, the joint is made of a eutectic alloy with silicon (for example, an Al-Si eutectic alloy), so there is a large amount of Si phase in the joint, and when used in a high-temperature environment, the Si phase in the joint can become the starting point for fracture, which may cause cracks in the joint, resulting in insufficient heat resistance. In addition, voids and shrinkage cavities may occur in the joint, which may reduce the joint strength.

[0008] The present invention has been made in view of the above circumstances, and aims to provide a silicon member that has sufficiently high bonding strength, excellent heat resistance, and can be used stably even in high-temperature environments, and a method for manufacturing the silicon member. [Means for solving the problem]

[0009] To solve the above problems, the silicon member of embodiment 1 of the present invention is a silicon member in which a plurality of plate-shaped members made of a Si-containing material are joined in the thickness direction, characterized in that the area ratio of the Si phase in the bonding layer formed between the plate-shaped members is 12% or less, and the bonding layer is made of metal.

[0010] According to the silicon member of embodiment 1 of the present invention, the area ratio of the Si phase in the bonding layer formed between the plate-like members is 12% or less, so the formation of coarse Si phase in the bonding layer is suppressed, and even when used in a high-temperature environment, damage to the bonding layer can be suppressed, resulting in excellent heat resistance. In addition, there are few shrinkage cavities or voids in the bonding layer, resulting in excellent bonding strength.

[0011] (delete)

[0012] Aspect 2 of the present invention is characterized in that, in the silicon member of aspect 1 of the present invention, the bonding layer is composed of Al or an Al-containing metal. According to the silicon member of embodiment 3 of the present invention, since the bonding layer is made of Al or an Al-containing metal, a plurality of plate-shaped members made of Si-containing material can be reliably bonded in the thickness direction.

[0013] A third aspect of the present invention is characterized in that, in the silicon member of the second aspect of the present invention, the bonding layer is composed of an Al-Si alloy having a Si content in the range of 0.5 mass% to 12.6 mass%. According to the silicon member of embodiment 3 of the present invention, since the bonding layer is composed of an Al-Si alloy with a Si content in the range of 0.5 mass% to 12.6 mass%, multiple plate-shaped members made of Si-containing material can be reliably bonded in the thickness direction. Furthermore, since the area ratio of the Si phase in the bonding layer is suppressed to 12% or less, damage to the bonding layer can be suppressed even when used in a high-temperature environment, and the heat resistance is particularly excellent.

[0014] Aspect 4 of the present invention is characterized in that, in a silicon member according to aspect 2 or aspect 3 of the present invention, when line analysis is performed along a virtual line extending in the thickness direction of the silicon member, the number of intersections between the Si peak and the Al peak on the virtual line is 4 or less in the bonding layer. According to the silicon member of embodiment 4 of the present invention, when line analysis is performed along a virtual line extending in the thickness direction of the silicon member, the number of intersections between the Si peak and the Al peak on the virtual line is 4 or less in the bonding layer. Therefore, the number of Si phases present in the bonding layer is small, and even when used in a high-temperature environment, damage to the bonding layer can be suppressed, resulting in particularly excellent heat resistance.

[0015] A method for manufacturing a silicon member according to aspect 5 of the present invention is a method for manufacturing a silicon member according to any one of aspects 1 to 4 of the present invention, characterized by comprising: a lamination step of arranging a bonding material between a plurality of plate-shaped members to form a laminate of the plurality of plate-shaped members and the bonding material; and a pressurizing and heating step of heating the laminate to a temperature below the liquidus temperature of the bonding material while pressurizing it in the lamination direction.

[0016] According to the method for manufacturing a silicon member of embodiment 5 of the present invention, the bonding material is heated to a temperature below the liquidus temperature during the pressurizing and heating process, so that the area ratio of the Si phase in the bonding layer can be kept to 12% or less. Therefore, the formation of a coarse Si phase in the bonding layer can be suppressed, and a silicon member with excellent heat resistance can be manufactured. Furthermore, since virtually no liquid phase is generated during the pressurizing and heating process, the overflow of the bonding material can be suppressed, and shrinkage cavities and voids are not formed in the bonding layer, thereby improving the bonding strength.

[0017] The method for manufacturing a silicon member according to aspect 6 of the present invention is characterized in that, in the method for manufacturing a silicon member according to aspect 5 of the present invention, the bonding material is made of Al or a metal containing Al. According to the method for manufacturing a silicon member of embodiment 6 of the present invention, since the bonding material is composed of Al or a metal containing Al, a plurality of plate-shaped members made of Si-containing material can be reliably bonded together.

[0018] The method for manufacturing a silicon member according to aspect 7 of the present invention is characterized in that, in the method for manufacturing a silicon member according to aspect 6 of the present invention, the bonding material is an Al-Si alloy having a Si content in the range of 0.5 mass% to 12.6 mass%. According to the method for manufacturing a silicon member of embodiment 7 of the present invention, since the bonding material is composed of an Al-Si alloy with a Si content in the range of 0.5 mass% to 12.6 mass% or less, the diffusion of Si from the plate-like member to the bonding layer can be suppressed, and the area ratio of the Si phase in the bonding layer can be sufficiently low.

[0019] The manufacturing method of the silicon member according to Embodiment 8 of the present invention is the manufacturing method of the silicon member according to any one of Embodiments 5 to 7 of the present invention, and before the lamination step, it has an Al layer forming step of forming an Al layer on the bonding surface of the plate-like member. In the lamination step, a plurality of the plate-like members are arranged such that the Al layers thereof face each other, and a bonding material is arranged so as to contact the opposing Al layers, and a laminate of the plurality of the plate-like members and the bonding material is formed.

[0020] According to the manufacturing method of the silicon member according to Embodiment 8 of the present invention, an Al layer is formed on the bonding surface of the plate-like member, a bonding material is arranged so as to contact this Al layer to form a laminate, and this laminate is heated to a temperature lower than the liquidus temperature of the bonding material while being pressurized in the lamination direction. Therefore, the diffusion of Si from the plate-like member to the bonding material is suppressed by the Al layer. Thus, the formation of coarse Si phases in the bonding layer can be suppressed, and a silicon member having excellent heat resistance can be manufactured.

Advantages of the Invention

[0021] According to the present invention, it is possible to provide a silicon member having a sufficiently high bonding strength, excellent heat resistance, and capable of being stably used even in a high-temperature environment, and a manufacturing method of this silicon member.

Brief Description of the Drawings

[0022] [Figure 1] It is an explanatory view showing an example of a silicon member according to an embodiment of the present invention. (a) is a perspective view, and (b) is an enlarged explanatory view of the bonding layer. [Figure 2] It is an explanatory view of a boundary point between a Si phase and an Al phase existing on a virtual line extending in the thickness direction of the bonding layer of the silicon member according to an embodiment of the present invention. [Figure 3] It is a flowchart showing a manufacturing method of a silicon member according to an embodiment of the present invention. [Figure 4] It is an explanatory view showing a manufacturing method of a silicon member according to an embodiment of the present invention. [Figure 5] These are photographs of the bonding layer of the silicon member in Example 1 of the present invention. (a) is an SEM image, (c) is the mapping result for Al, and (d) is the mapping result for Si. [Figure 6] These are photographs of the bonding layer of the silicon member in Example 6 of the present invention. (a) is an SEM image, (b) is the line analysis result of Al and Si, (c) is the mapping result of Al, and (d) is the mapping result of Si. [Figure 7] These are photographs of the bonding layer of the silicon component in Comparative Example 1. (a) is an SEM image, (b) is the line analysis result of Al and Si, (c) is the Al mapping result, and (d) is the Si mapping result. [Figure 8] This is a schematic diagram illustrating the tensile test in the embodiment. (a) is the test specimen, (b) is the test specimen and tensile test fixture, and (c) is the tensile testing machine. [Modes for carrying out the invention]

[0023] The following describes a silicon member and a method for manufacturing the silicon member, which are embodiments of the present invention. In this embodiment, the silicon component is, for example, a silicon component disposed in a chamber in a plasma processing apparatus such as a plasma etching apparatus or a plasma CVD apparatus used in a semiconductor device manufacturing process. In this embodiment, it is a silicon electrode plate with a structure in which multiple ventilation holes are formed in a silicon plate material. In other words, in this embodiment, multiple silicon electrode plates that have been worn out through use are bonded together and used as a recycled silicon electrode plate.

[0024] As shown in Figure 1(a), the silicon member 10 (recycled silicon electrode plate) of this embodiment is provided with a plurality of ventilation holes 10A that penetrate in the thickness direction. In this embodiment, the silicon member 10 has a structure in which a first plate-shaped member 11 and a second plate-shaped member 12 are joined in the thickness direction, as shown in Figures 1(a) and (b), and a joining layer 20 is formed between the first plate-shaped member 11 and the second plate-shaped member 12.

[0025] The first plate-shaped member 11 and the second plate-shaped member 12 are made of a Si-containing material such as silicon, silicon nitride, or silicon carbide. Furthermore, the area ratio of the Si phase 25 in the bonding layer 20 formed between the first plate-like member 11 and the second plate-like member 12 is set to 12% or less. Furthermore, it is more preferable that the area ratio of the Si phase 25 in the bonding layer 20 be 10% or less, and even more preferable that it be 8% or less. In this embodiment, the area ratio of the Si phase 25 in the bonding layer 20 is the area ratio in the cross-section of the bonding layer 20 along the stacking direction of the silicon member 10.

[0026] Furthermore, in this embodiment, it is preferable that the aspect ratio of the Si phase 25 in the bonding layer 20 is 3.0 or less. Furthermore, it is even more preferable that the aspect ratio of the Si phase 25 in the bonding layer 20 is 2.5 or less. The morphology of the Si phase 25 in the bonding layer 20 is preferably spherical.

[0027] Furthermore, in this embodiment, the bonding layer 20 is preferably made of Al or an Al-containing metal. Furthermore, the bonding layer 20 is preferably an Al-Si alloy with a Si content in the range of 0.5 mass% to 12.6 mass%. Moreover, the bonding layer 20 is even more preferably an Al-Si alloy with a Si content in the range of 0.5 mass% to 8.0 mass%.

[0028] Furthermore, in this embodiment, if the bonding layer 20 is made of Al or an Al-containing metal, as shown in Figure 2, when line analysis is performed along a virtual line P extending in the thickness direction of the silicon member 10, it is preferable that the number of intersections between the Si peak and the Al peak on the virtual line P is 4 or less in the bonding layer 20. In this case, as shown in Figure 2, the Si peak will represent the Si phase 25 in the first plate-like member 11, the second plate-like member 12, and the bonding layer 20. The Al peak will represent the bonding layer 20, which is composed of Al or an Al-containing metal. Therefore, the boundary between the first plate-like member 11 and the bonding layer 20, and the boundary between the second plate-like member 12 and the bonding layer 20, are also intersection points of the Si peak and the Al peak in the bonding layer 20.

[0029] Next, the manufacturing method of the silicon member 10 according to this embodiment will be described with reference to Figures 3 and 4.

[0030] In the manufacturing method of the silicon member 10 according to this embodiment, as shown in Figures 3 and 4, the method includes a surface grinding step S01 for grinding the surfaces of the first plate-shaped member 11 and the second plate-shaped member 12, which are used silicon electrode plates; an Al layer forming step S02 for forming an Al layer 21 on the joining surfaces of the first plate-shaped member 11 and the second plate-shaped member 12, respectively; a lamination step S03 for forming a laminate of the first plate-shaped member 11, a bonding material 35, and the second plate-shaped member 12; and a pressurizing and heating step S04 for heating the laminate while pressurizing it in the lamination direction.

[0031] The following describes in detail each step of the manufacturing method for the silicon member 10 according to this embodiment.

[0032] (Surface grinding process S01) In this embodiment, as shown in Figure 4, two used silicon electrode plates are prepared. Next, the surface (plasma surface) of the silicon electrode plate is ground using a grinding machine 40. This yields the first plate-shaped member 11 and the second plate-shaped member 12. By grinding the plasma surface, the plasma-side portion of the ventilation holes, which have expanded due to wear during use, is removed.

[0033] (Al layer formation step S02) Next, an Al layer 21 is formed on the joining surfaces of the first plate-shaped member 11 and the second plate-shaped member 12, respectively. There are no particular restrictions on the method for forming the Al layer 21, and various existing methods such as vapor deposition and sputtering can be appropriately selected. In this embodiment, the Al layer 21 is formed by sputtering using an Al sputtering target. The thickness of the Al layer 21 is preferably within the range of 0.05 μm to 2 μm.

[0034] (Lamination process S03) Next, the first plate-shaped member 11 and the second plate-shaped member 12 are arranged so that their respective Al layers 21, 21 face each other, and the bonding material 35 is placed in contact with the opposing Al layers 21, 21 to form a laminate of the first plate-shaped member 11, the bonding material 35, and the second plate-shaped member 12. Here, the bonding material 35 is preferably composed of Al or a metal containing Al. In this embodiment, it is preferable to use an Al-Si alloy as the bonding material 35 having a Si content in the range of 0.5 mass% to 12.6 mass%.

[0035] (Pressurization and heating process S04) Next, the laminate is heated under pressure in the stacking direction, and the first plate-shaped member 11 and the second plate-shaped member 12 are joined via the bonding layer 20. The Al layers 21, 21 formed on the joining surfaces of the first plate-shaped member 11 and the second plate-shaped member 12 are incorporated into the bonding layer 20 during the heating process S04.

[0036] Here, the holding temperature in the pressurizing and heating process S04 is set below the melting point of the Al layer 21 or below the liquidus temperature of the bonding material 35 in order to keep the area ratio of the Si phase in the bonding layer 20 to 12% or less. In this embodiment, when using Al or Al-Si alloy with a Si content in the range of 0 mass% to 12.6 mass% as the bonding material 35, it is preferable that the holding temperature be in the range of 500°C to 650°C. Also, in this embodiment, when joining using the Al layer 21 formed on the joining surface of the first plate-shaped member 11 and the second plate-shaped member 12 (when the Al layer 21 is used as the bonding material), it is preferable that the holding temperature be in the range of 500°C to 650°C. Furthermore, when using an Al-Si alloy as the bonding material 35, with an Al or Si content in the range of 0.5 mass% to 12.6 mass%, it is even more preferable to set the lower limit of the holding temperature to 550°C or higher, and more preferably to 580°C or higher. It is also even more preferable to set the upper limit of the holding temperature to 640°C or lower, and more preferably to 600°C or lower.

[0037] Furthermore, it is preferable that the holding time in the pressurizing and heating process S04 be within the range of 1 hour to 16 hours. Furthermore, the lower limit of the holding time is more preferably 1.5 hours or more, and more preferably 2 hours or more. The upper limit of the holding time is more preferably 8 hours or less, and more preferably 6 hours or less.

[0038] Furthermore, it is preferable that the pressing load in the stacking direction during the pressing and heating process S04 be within the range of 0.01 MPa to 10 MPa. Furthermore, the lower limit of the pressurized load in the stacking direction is more preferably 0.03 MPa or higher, and more preferably 0.1 MPa or higher. Also, the upper limit of the pressurized load in the stacking direction is more preferably 8 MPa or lower, and more preferably 6 MPa or lower.

[0039] Through the various processes described above, the silicon member 10 (recycled silicon electrode plate) of this embodiment can be manufactured.

[0040] In the silicon member 10 of this embodiment, which has the above configuration, the area ratio of the Si phase 25 in the bonding layer 20 formed between the first plate-shaped member 11 and the second plate-shaped member 12 is set to 10% or less. Therefore, the formation of coarse Si phase 25 in the bonding layer 20 is suppressed, and damage to the bonding layer 20 can be suppressed even when used in a high-temperature environment, resulting in excellent heat resistance. In addition, since a large amount of liquid phase is not generated during bonding, there are no shrinkage cavities or voids in the bonding layer 20, resulting in excellent bonding strength.

[0041] In the silicon member 10 of this embodiment, when the aspect ratio of the Si phase 25 in the bonding layer 20 is 3.0 or less, even when used in a high-temperature environment, damage to the bonding layer 20 caused by the Si phase 25 can be suppressed, and the heat resistance is particularly excellent.

[0042] Furthermore, in the silicon member 10 of this embodiment, if the bonding layer 20 is made of Al or an Al-containing metal, the first plate-shaped member 11 and the second plate-shaped member 12 made of Si-containing material can be reliably bonded in the thickness direction.

[0043] Furthermore, in the silicon member 10 of this embodiment, if the bonding layer 20 is made of an Al-Si alloy with a Si content in the range of 0.5 mass% to 12.6 mass%, the diffusion of Si from the first plate-shaped member 11 and the second plate-shaped member 12, which are made of Si-containing material, to the bonding layer 20 can be suppressed, and the area ratio of the Si phase in the bonding layer 20 can be sufficiently reduced.

[0044] In the manufacturing method of the silicon member 10 of this embodiment, the bonding material 35 is heated to a temperature below the liquidus temperature in the pressurizing and heating step S04. As a result, a large amount of liquid phase is not generated during bonding, and the area ratio of the Si phase 25 in the bonding layer 20 can be kept to 12% or less. Therefore, the formation of coarse Si phase 25 in the bonding layer 20 can be suppressed, and a silicon member 10 with excellent heat resistance can be manufactured. Furthermore, since a large amount of liquid phase is not generated during the pressurizing and heating process S04, the overflow of the bonding material 35 can be suppressed, and shrinkage cavities and voids are not formed in the bonding layer 20, thereby improving the bonding strength.

[0045] In the manufacturing method of the silicon member 10 of this embodiment, if the bonding material 35 is made of Al or an Al-containing metal, the first plate-shaped member 11 and the second plate-shaped member 12 made of a Si-containing material can be reliably bonded together.

[0046] Furthermore, in the manufacturing method of the silicon member 10 of this embodiment, since the bonding material 35 is made of an Al-Si alloy with a Si content in the range of 0.5 mass% to 12.6 mass%, the diffusion of Si from the first plate-shaped member 11 and the second plate-shaped member 12 to the bonding layer 20 can be sufficiently suppressed, and the area ratio of the Si phase 25 in the bonding layer 20 can be sufficiently low.

[0047] Furthermore, in the manufacturing method of the silicon member 10 of this embodiment, if an Al layer forming step S02 is performed before the lamination step S03 to form an Al layer 21 on the joining surface of the first plate-shaped member 11 and the second plate-shaped member 12, and in the lamination step S03 the first plate-shaped member 11 and the second plate-shaped member 12 are arranged so that their Al layers 21, 21 face each other, and a bonding material 35 is placed in contact with the opposing Al layers 21, 21 to form a laminate of the first plate-shaped member 11, the bonding material 35 and the second plate-shaped member 12, then the formation of a coarse Si phase 25 in the bonding layer 20 can be suppressed, and a silicon member 10 with excellent heat resistance can be manufactured.

[0048] Although embodiments of the present invention have been described above, the present invention is not limited thereto and can be modified as appropriate without departing from the technical spirit of the invention. For example, in this embodiment, the silicon member was described as a recycled silicon electrode plate formed by joining two used silicon electrode plates, but it is not limited to this. The silicon member may be any plate-shaped member made of Si-containing material that is joined together, or it may be a plate-shaped member made of three or more joined together.

[0049] Furthermore, although this embodiment describes forming an Al layer on the joining surface of the first plate-shaped member and the second plate-shaped member and joining them via a bonding material, it is not limited to this, and the members may be joined by placing a bonding material between the first plate-shaped member and the second plate-shaped member without forming an Al layer on the joining surface. [Examples]

[0050] The results of the verification experiments conducted to confirm the effectiveness of the present invention are described below.

[0051] A silicon plate-shaped member (φ125mm × 5mmt) was prepared. In Examples 1-3, 6, and 7 of the present invention, an Al layer (underlying Al layer) was sputtered onto the joining surface of the plate-shaped member using an Al sputtering target, as shown in Table 1. The joining materials shown in Table 1 were also prepared. A laminate was formed by stacking the prepared plate-like members and bonding material. Two plate-like members were joined to this laminate by applying pressure and heating under the conditions shown in Table 1, thereby producing various silicon members having a bonding layer. The obtained silicon components were evaluated as follows.

[0052] (Area ratio of the Si phase) The cross-section of the silicon component was observed along the lamination direction, and the bonding layer in that cross-section was mapped for Si and the elements constituting the bonding layer (hereinafter referred to as bonding layer elements) at a 5000x magnification field of view. For each mapping result, a semi-quantitative calculation was performed for each pixel using the quantitative mapping function of the instrument's software, assuming that only Si and bonding layer elements were present, and a quantitative map showing the content (weight %) for each pixel was created. Based on the created quantitative map, the phase with a Si content of 99 mass% or more in the bonding layer within the field of view was defined as the Si phase, and the area ratio of the Si phase in the bonding layer within the field of view was calculated. The area fraction of the Si phase within the contour of the bonding layer was calculated within the field of view. Multiple fields of view (3 fields of view / 3 images) were used for the calculation, and the area fraction was the average of these values. The observation magnification should be selected so that the upper and lower interfaces of the bonding layer are within the field of view. Here, the observation results (SEM cross-sectional structure) and mapping results for Example 1 of the present invention are shown in Figure 5, the observation results (SEM cross-sectional structure), elemental line analysis results, and mapping results for Example 6 of the present invention are shown in Figure 6, and the observation results (SEM cross-sectional structure), elemental line analysis results, and mapping results for Comparative Example 1 are shown in Figure 7.

[0053] (Aspect ratio of the Si phase) The aspect ratio of the Si phase obtained above was calculated using commercially available image analysis software (WIN Roof), and its average was determined. The longest dimension of the observed Si phase was defined as the major axis length, and the longest dimension in the direction perpendicular to this major axis was defined as the minor axis length. The aspect ratio was defined as major axis length / minor axis length.

[0054] (Number of intersections between Al peak and Si peak) The cross-section of the obtained silicon member along the lamination direction was observed, and SEM-EDS (elemental line analysis) was performed on the bonding layer in that cross-section. A virtual line was drawn extending in the thickness direction of the bonding layer in the cross-section including the bonding layer, and the number of intersections between the Al peak and the Si peak on the extending virtual line was counted. The line analysis results by SEM-EDS for Example 6 of the present invention and Comparative Example 1 are shown in Figure 6(b) and Figure 7(b), respectively.

[0055] (External observation) The obtained silicon components were visually inspected to evaluate the presence or absence of adhesive overflow and cracks. Components with adhesive overflow and cracks were marked with "×", those with adhesive overflow but no cracks were marked with "△", and those with neither adhesive overflow nor cracks were marked with "〇".

[0056] (Joining strength) As shown in Figure 8, the obtained silicon material was cut into 10 mm squares, and the sides opposite to the joint surface of the plate-shaped material were bonded to the tensile test fixture using adhesive. Then, it was set in a universal tensile testing machine, and a tensile test was performed at a speed of 0.1 mm / min. If the bonding strength between the plate-shaped material and the tensile test fixture using adhesive exceeded 15 MPa, it was indicated as "15 MPa or more".

[0057] (Heat resistance test) The obtained silicon components were held at 300°C for 24 hours, and their appearance was visually inspected thereafter to check for cracks or delamination. For components where no cracks or delamination were observed visually, ultrasonic testing was performed before and after heating to 300°C. Based on the results, components where cracks or delamination were observed were marked with "×", those where no cracks or delamination were observed but a change in the ultrasonic testing image (change in bonding ratio) was observed were marked with "〇", and those where no change in the ultrasonic testing image (change in bonding ratio) was observed were marked with "◎".

[0058] [Table 1]

[0059] In Comparative Example 1, no Al layer was formed on the joint surface of the plate-shaped member, and Al was used as the bonding material. The members were bonded under no pressure and at a holding temperature of 800°C. As a result, the area ratio of the Si phase in the bonded layer was 13%, and the aspect ratio of the Si phase was 4.5. In addition, the number of intersections between the Al peak and the Si peak was 10, indicating a large number of Si phases present in the bonded layer. Furthermore, the bond strength was low at 4.1 MPa, and cracks and delamination were observed after the heat resistance test. In addition, excess bonding material was observed in the resulting silicon member.

[0060] In Comparative Example 2, no Al layer was formed on the joint surface of the plate-shaped members, and Al was used as the bonding material. The members were bonded under conditions of a pressurized load of 3 MPa and a holding temperature of 800°C. As a result, the area ratio of the Si phase in the bonded layer was 14%, and the aspect ratio of the Si phase was 4.3. In addition, the number of intersections between the Al peak and the Si peak was 12, indicating a large number of Si phases present in the bonded layer. The bonded strength was low at 5.3 MPa, and cracks and delamination were observed after the heat resistance test. Furthermore, the resulting silicon member showed extrusion of the bonding material and cracking.

[0061] In Comparative Example 3, an Al layer was not formed on the joining surface of the plate-shaped members, and Al was used as the joining material. An attempt was made to join them under the conditions of a pressurized load of 3 MPa and a holding temperature of 600°C, but it was not possible to join the plate-shaped members together, and a silicon member could not be obtained.

[0062] In contrast, in Example 1 of the present invention, an Al layer was formed on the joining surface of a plate-shaped member, and Al was used as the joining material. The members were joined under conditions of a pressurized load of 3 MPa and a holding temperature of 600°C. As a result, the area ratio of the Si phase in the joining layer was 0%, and the number of intersections between the Al peak and the Si peak was 2, indicating that no Si phase was present in the joining layer. Furthermore, the joining strength was high, at 15 MPa or more, and no cracks or peeling were observed after the heat resistance test. In addition, no overflow of the joining material was observed in the obtained silicon member. As shown in Figure 5, it was confirmed that no Si phase was present in the joining layer. It is presumed that the diffusion of Si from the plate-shaped member to the joining layer was suppressed by the Al layer.

[0063] In Example 2 of the present invention, an Al layer was formed on the joining surface of a plate-shaped member, and Al was used as the joining material. The members were joined under conditions of a pressurized load of 3 MPa and a holding temperature of 550°C. As a result, the area ratio of the Si phase in the joining layer was 0%, and the number of intersections between the Al peak and the Si peak was 2, indicating that no Si phase was present in the joining layer. Furthermore, the joining strength was high, at 15 MPa or more, and no cracks or peeling were observed after the heat resistance test. No changes in the ultrasonic flaw detection image (change in bonding ratio) were also observed. In addition, no overflow of the joining material was observed in the obtained silicon member.

[0064] In Example 3 of the present invention, an Al layer was formed on the joint surface of a plate-shaped member, and an Al-7.5mass%Si alloy was used as the bonding material. The members were bonded under conditions of a pressurized load of 3 MPa and a holding temperature of 600°C. As a result, the area ratio of the Si phase in the bonded layer was 7.8%, and the aspect ratio of the Si phase was 2.2. In addition, the number of intersections between the Al peak and the Si peak was 8. Furthermore, the bonding strength was high at 15 MPa or more, no cracks or peeling were observed after the heat resistance test, and no changes in the ultrasonic flaw detection image (change in bonding ratio) were observed. In addition, no overflow of the bonding material was observed in the obtained silicon member.

[0065] In Example 4 of the present invention, an Al layer was not formed on the joint surface of the plate-shaped members. An Al-7.5mass%Si alloy was used as the joining material, and the members were joined under conditions of a pressurized load of 3 MPa and a holding temperature of 600°C. As a result, the area ratio of the Si phase in the joint layer was 8.0%, and the aspect ratio of the Si phase was 2.9. In addition, the number of intersections between the Al peak and the Si peak was 6. The joint strength was relatively high at 14.1 MPa, and no cracks or peeling were observed after the heat resistance test. Furthermore, no overflow of the joining material was observed in the obtained silicon member. As shown in Figure 6, although a small amount of Si phase is present in the joint layer, it is confirmed that the aspect ratio of the Si phase is sufficiently small.

[0066] In Example 5 of the present invention, an Al layer was not formed on the joint surface of the plate-shaped member. An Al-2.0mass%Si alloy was used as the joining material, and the members were joined under conditions of a pressurized load of 3 MPa and a holding temperature of 600°C. As a result, the area ratio of the Si phase in the joint layer was 2.4%, and the aspect ratio of the Si phase was 2.4. In addition, the number of intersections between the Al peak and the Si peak was 4. Furthermore, the joint strength was high at 15 MPa or more, no cracks or peeling were observed after the heat resistance test, and no changes in the ultrasonic flaw detection image (change in joint ratio) were observed. In addition, no overflow of the joining material was observed in the obtained silicon member.

[0067] In Example 6 of the present invention, an Al layer was formed on the joining surface of a plate-shaped member, and the members were joined without using a bonding material under conditions of a pressurized load of 3 MPa and a holding temperature of 600°C. As a result, the area ratio of the Si phase in the bonding layer was 0%, and the number of intersections between the Al peak and the Si peak was 2, indicating that no Si phase was present in the bonding layer. Furthermore, the bonding strength was high, at 15 MPa or more, and no cracks or peeling were observed after the heat resistance test, nor was any change in the ultrasonic flaw detection image (change in bonding ratio) observed. In addition, no overflow of bonding material was observed in the obtained silicon member. As shown in Figure 6, it was confirmed that no Si phase was present in the bonding layer.

[0068] In Example 7 of the present invention, an Al layer was formed on the joining surface of a plate-shaped member, and pure Al was used as the bonding material. The members were bonded under conditions of a pressurized load of 3 MPa and a holding temperature of 600°C. As a result, the area ratio of the Si phase in the bonding layer was 0%, and the number of intersections between the Al peak and the Si peak was 2, indicating that no Si phase was present in the bonding layer. Furthermore, the bonding strength was high, at 15 MPa or more, and no cracks or peeling were observed after the heat resistance test. No changes in the ultrasonic flaw detection image (changes in bonding ratio) were observed either. In addition, no overflow of the bonding material was observed in the obtained silicon member.

[0069] As a result of the above, it has been confirmed that, according to the present invention, it is possible to provide a silicon component that has sufficiently high bonding strength, excellent heat resistance, and can be used stably even in high-temperature environments, as well as a method for manufacturing this silicon component. [Explanation of Symbols]

[0070] 10. Silicon material (recycled silicon electrode plate) 11. First plate-shaped member 12. Second plate-shaped member 20 Bonding layer 21 Al layer 25 Si phase

Claims

1. A silicon member in which multiple plate-shaped members made of a Si-containing material are joined together in the thickness direction, The area ratio of the Si phase in the bonding layer formed between the plate-like members is 12% or less. A silicon member characterized in that the bonding layer is made of metal.

2. The silicon member according to claim 1, characterized in that the bonding layer is composed of Al or a metal containing Al.

3. The silicon member according to claim 2, characterized in that the bonding layer is composed of an Al-Si alloy having a Si content in the range of 0.5 mass% to 12.6 mass%.

4. The silicon member according to claim 2, characterized in that, when line analysis is performed along a virtual line extending in the thickness direction of the silicon member, the number of intersections between the Si peak and the Al peak on the virtual line is 4 or less in the bonding layer.

5. A method for manufacturing a silicon member according to any one of claims 1 to 4, A lamination step in which a bonding material is placed between a plurality of plate-shaped members to form a laminate of the plurality of plate-shaped members and the bonding material, A pressurizing and heating step in which the laminate is heated to a temperature below the liquidus temperature of the bonding material while under pressure in the stacking direction, A method for manufacturing a silicon component, characterized by having the following features.

6. The method for manufacturing a silicon member according to claim 5, characterized in that the bonding material is composed of Al or a metal containing Al.

7. The method for manufacturing a silicon member according to claim 6, characterized in that the bonding material is composed of an Al-Si alloy having a Si content in the range of 0.5 mass% to 12.6 mass%.

8. Prior to the lamination process, there is an Al layer forming step in which an Al layer is formed on the joining surface of the plate-shaped member. The method for manufacturing a silicon member according to claim 5, characterized in that, in the lamination step, a plurality of the plate-shaped members are arranged so that their Al layers face each other, and a bonding material is placed in contact with the opposing Al layers to form a laminate of the plurality of plate-shaped members and the bonding material.

Images