Diamond joint, electronic device, and method for manufacturing a diamond joint

Abstract

To provide a novel diamond bonded body using single crystal diamond and polycrystal diamond having uniform surface properties.SOLUTION: A diamond bonded body is obtained by bonding single crystal diamond and polycrystal diamond. In a boned surface between the single crystal diamond and the polycrystal diamond, a surface of the single crystal diamond has a plurality of plane orientations, in surface analysis by a scanning electron microscope, the polycrystal diamond has a crystal grain size of less than 10 μm, and on a reverse pole figure orientation map using electron beam back-scattering diffraction, two or more kinds of crystal orientations are observed on all single crystal surfaces.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a diamond bond, an electronic device, and a method for manufacturing a diamond bond. [Background technology]

[0002] Diamond, possessing excellent semiconductor properties, is expected to be a promising material for semiconductor devices such as high-power devices, high-frequency devices, and photodetectors.

[0003] Furthermore, diamond junctions, which utilize scribing wheels or diamond points made of single-crystal diamonds, are used to scribe glass substrates, silicon wafers, and other materials.

[0004] Furthermore, diamond is expected to have applications in sliding components such as mechanical seals, and in dielectric windows that take advantage of its low loss and high thermal conductivity. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Unexamined Patent Publication No. 7-48198 [Patent Document 2] Japanese Patent Publication No. 2013-043787 [Overview of the project] [Problems that the invention aims to solve]

[0006] The surface of a single-crystal diamond has various crystal orientations, such as the

[0100] plane,

[0111] plane, and

[0110] plane, each with different properties. Therefore, when using the surface of a single-crystal diamond, it is necessary to consider the crystal orientation of the surface.

[0007] The main objective of this invention is to provide a novel diamond composite utilizing single-crystal diamond and polycrystalline diamond, wherein the polycrystalline diamond possesses uniform surface properties. [Means for solving the problem]

[0008] The inventors diligently conducted research to solve the above-mentioned problems. As a result, they found that by attaching nanodiamonds to at least a portion of the surface of a single-crystal diamond and then forming a polycrystalline diamond, a polycrystalline diamond with uniform surface properties is formed, regardless of the surface orientation of the single-crystal diamond. Such a bond between single-crystal diamond and polycrystalline diamond can be applied to a wide range of applications such as electronic devices, optical elements, sliding members, and diamond tools by utilizing the surface of the polycrystalline diamond with uniform surface properties. When applying diamond to electronic devices, for example, a structure in which a localized contact layer of polycrystalline diamond is provided on a single-crystal diamond substrate can be envisioned. Furthermore, heterojunction devices of single-crystal diamond substrate / polycrystalline diamond can also be envisioned. In addition, by utilizing the slight difference in band gap, application to diodes can also be envisioned.

[0009] This invention was completed through further investigation based on these findings.

[0010] In other words, the present invention provides inventions in the following embodiments. Item 1. A bonded body of single-crystal diamond and polycrystalline diamond, At the bonding surface between the single-crystal diamond and the polycrystalline diamond, the surface of the single-crystal diamond has multiple surface orientations. The aforementioned polycrystalline diamond is a diamond composite in which, in surface analysis by scanning electron microscopy, the crystal grain size is less than 10 μm, and two or more crystal orientations are observed on all single crystal planes in an inverse pole figure orientation map using electron backscatter diffraction. Item 2. The diamond bonded body according to Item 1, wherein at least one of the single crystal diamond and the polycrystalline diamond contains a metal element. Item 3. The diamond bonded body according to Item 1 or 2, wherein at least one of the single crystal diamond and the polycrystalline diamond contains an impurity. Item 4. The diamond bonded body according to Item 3, wherein the impurity is at least one selected from the group consisting of boron, phosphorus, and nitrogen. Item 5. The diamond bonded body according to any one of Items 1 to 4, wherein on the bonding surface between the single crystal diamond and the polycrystalline diamond, the surface of the single crystal diamond includes at least one surface orientation of the

[0100] plane, the

[0111] plane, and the

[0110] plane. Item 6. The diamond bonded body according to any one of Items 1 to 5, wherein in the polycrystalline diamond layer, the ratio of the crystal grain size of the

[0111] plane to the

[0110] plane is 2 or less. Item 7. An electronic device, an optical element, or a sliding member including the diamond bonded body according to any one of Items 1 to 6. Item 8. A method for manufacturing a diamond bonded body according to any one of Items 1 to 6, a step of attaching diamond particles to the surface of the single crystal diamond; a step of forming polycrystalline diamond on the surface of the single crystal diamond to which the diamond particles are attached by a hot filament CVD method; and a method for manufacturing a diamond bonded body including the above steps.

Advantages of the Invention

[0011] According to the present invention, there is provided a novel diamond bonded body using a single crystal diamond and a polycrystalline diamond, in which the polycrystalline diamond has uniform surface characteristics.

Brief Description of the Drawings

[0012] [Figure 1]This image was obtained by observing the surface of a polycrystalline diamond, formed by depositing diamond particles onto the

[0111] ,

[0110] , and

[0100] planes of a single-crystal diamond, using a scanning electron microscope (SEM) (Example 1). [Figure 2] This image was obtained by observing the surface of a polycrystalline diamond, formed without attaching diamond particles to the

[0111] ,

[0110] , and

[0100] planes of a single-crystal diamond, using a scanning electron microscope (SEM) (Reference Example 1). [Figure 3] This is an inverse pole-direction map obtained using electron backscatter diffraction for the surface of a polycrystalline diamond formed by depositing diamond particles onto the

[0111] and

[0110] planes of a single-crystal diamond (Example 1). [Modes for carrying out the invention]

[0013] The diamond bonded body of the present invention is a bonded body of single-crystal diamond and polycrystalline diamond, wherein at the bonding surface between the single-crystal diamond and the polycrystalline diamond, the surface of the single-crystal diamond has multiple plane orientations, and the polycrystalline diamond is characterized in that, in surface analysis by scanning electron microscopy, the grain size is less than 10 μm, and two or more crystal orientations are observed on all single-crystal planes (e.g., the

[0100] plane, the

[0111] plane, the

[0110] plane, etc.) in an inverse pole figure orientation map using electron backscatter diffraction. More specifically, for example, if the surface of the polycrystalline diamond has the

[0100] plane, the

[0111] plane, and the

[0110] plane as single-crystal planes, two or more crystal orientations are observed on all of these single-crystal planes. By possessing these characteristics, the diamond bonded body of the present invention is a diamond bonded body utilizing single-crystal diamond and polycrystalline diamond, in which the polycrystalline diamond has uniform surface properties.

[0014] Specifically, the surface of a single-crystal diamond generally has various crystal orientations such as the

[0100] plane,

[0111] plane, and

[0110] plane, and its surface properties differ depending on the crystal orientation. In contrast, in the diamond composite of the present invention, polycrystalline diamond is formed on the surface of the single-crystal diamond so as to have a uniform surface. Therefore, the diamond composite of the present invention is less affected by the crystal orientation of the single-crystal diamond and exhibits excellent uniformity of surface properties as a diamond composite. Such a diamond composite can be suitably manufactured, for example, by attaching nanodiamonds to the surface of a single-crystal diamond and then growing polycrystalline diamond, as described later.

[0015] In the diamond bonded body of the present invention, the single crystal diamond is not particularly limited, and known single crystal diamonds used as diamond bonded bodies can be used. Known single crystal diamonds used as diamond bonded bodies include, for example, those used as base materials for diamond tools, as described in Japanese Patent Publication No. 2018-34381 and Japanese Patent Publication No. 2017-13488.

[0016] The shape and size of the single-crystal diamond can be appropriately set according to the type and application of the diamond composite. For example, the diameter of the single-crystal diamond may be 20 mm or less, 10 mm or less, preferably around 0.8 to 20 mm or 0.8 to 10 mm, and the thickness may be around 0.4 to 1.1 mm. Regarding the shape of the single-crystal diamond, for example, if the diamond composite of the present invention is a wheel (a form of diamond tool), the shape of the single-crystal diamond as the base material will also be wheel-shaped (disc-shaped). When the diamond composite of the present invention is a wheel, it can be suitably used as a scribe tool or the like. Furthermore, when the diamond composite of the present invention is used in an electronic device, the single-crystal diamond should have a shape and size suitable for the electronic device.

[0017] The surface of a single-crystal diamond typically has multiple plane orientations. That is, in the diamond composite of the present invention, the surface of the single-crystal diamond on which polycrystalline diamond is formed typically has multiple plane orientations. Specific examples of plane orientations include the

[0100] plane, the

[0111] plane, the

[0110] plane, and typically includes at least one of the

[0100] plane, the

[0111] plane, and the

[0110] plane.

[0018] Polycrystalline diamond only needs to be formed on at least a portion of the surface of a single-crystal diamond, and the portion on which the polycrystalline diamond with uniform surface properties is formed can be suitably utilized.

[0019] For example, in the case of a diamond composite having a cutting edge, it is sufficient for polycrystalline diamond to be formed on the surface of the cutting edge of a substrate made of single-crystal diamond. By further polishing the surface of the polycrystalline diamond, the processing characteristics with respect to the substrate can be made even more uniform, enabling precise processing.

[0020] As described below, the diamond composite of the present invention can be manufactured by forming polycrystalline diamond having uniform surface properties on at least a portion of the surface of a single-crystal diamond. The method for forming the polycrystalline diamond is not particularly limited, but it is preferable to grow polycrystalline diamond on the surface of a single-crystal diamond using methods such as chemical vapor deposition (e.g., thermal filament CVD method, microwave CVD method, etc.), and it is particularly preferable to use the thermal filament CVD method.

[0021] When forming polycrystalline diamond by the hot filament CVD method, it can be formed such that a metal element is contained in the polycrystalline diamond. Specifically, by forming polycrystalline diamond by the hot filament CVD method using a metal filament, the metal constituting the metal filament is contained in the polycrystalline diamond and becomes polycrystalline diamond. Regarding the method of forming a polycrystalline diamond doped with a metal (metal-doped polycrystalline diamond) by the hot filament CVD method, a known method can be adopted. Examples of specific methods for forming a polycrystalline diamond doped with a metal by the hot filament CVD method will be described later.

[0022] Specific examples of the metal elements contained in the polycrystalline diamond include tungsten, tantalum, rhenium, ruthenium, etc. The metal element contained in the polycrystalline diamond may be only one kind or two or more kinds.

[0023] The concentration of the metal element in the polycrystalline diamond is not particularly limited. For example, it is in the range of 1×10 18 ~1×10 22 atoms / cm 3 or so, preferably in the range of 1×10 19 ~1×10 22 atoms / cm 3 or so, more preferably in the range of 1×10 19 ~1×10 21 atoms / cm 3 or so, more preferably in the range of 1×10 20 ~1×10 21 atoms / cm 3 or so. The concentration of the metal element in the polycrystalline diamond is a value measured by secondary ion mass spectrometry (SIMS).

[0024] Furthermore, polycrystalline diamond can contain impurities such as boron, phosphorus, and nitrogen. For example, when forming polycrystalline diamond using the aforementioned thermal filament CVD method, impurity sources (such as trimethylboron and phosphine (PH3)) can be present along with carbon source gases (such as methane) to allow the polycrystalline diamond to contain impurities such as boron, phosphorus, and nitrogen. The impurity concentration in polycrystalline diamond can be, for example, 1 × 10⁻⁶. 18 ~1 × 10 22 atoms / cm 3 A range of approximately 1 × 10 18 ~1 × 10 21 atoms / cm 3 A range of approximately 1 × 10 19 ~1 × 10 21 atoms / cm 3 A range of approximately 1 × 10 20 ~1 × 10 21 atoms / cm 3 A range of degrees can be cited. The concentration of impurities in polycrystalline diamond is measured by secondary ion mass spectrometry (SIMS). Polycrystalline diamond may contain only one type of impurity, or two or more types.

[0025] As described above, in the manufacturing of the diamond composite of the present invention, when nanodiamonds are attached to the surface of a single-crystal diamond and then polycrystalline diamond is grown, a uniform polycrystalline diamond is formed in which the influence of the crystal orientation of the surface of the single-crystal diamond is particularly suitably reduced. Therefore, the diamond composite of the present invention has particularly uniform surface properties. The surface of the diamond composite with uniform surface properties can exhibit uniform processing properties, for example, and can therefore be suitably used as a diamond tool (e.g., a scribe tool). It can also be suitably used as a sliding member, optical member, or electronic device. For example, when a polycrystalline diamond layer is used as a contact layer, it is desirable that the crystal grain size is small and the surface irregularities are small. More specifically, a uniform polycrystalline diamond is a polycrystalline diamond in which, in surface analysis using a scanning electron microscope or the like, the grain size is less than 10 μm (preferably 0.1 to 5 μm, more preferably 0.1 to 3 μm), and in an inverse pole figure orientation map using electron beam backscatter diffraction, all single crystal planes (e.g., the

[0100] plane, the

[0111] plane, the

[0110] plane, etc.) have two or more types (e.g., 2 to 3 types) of crystal orientations. More specifically, in such a polycrystalline diamond layer, for example, if the surface of the polycrystalline diamond has the

[0100] plane, the

[0111] plane, and the

[0110] plane as single crystal planes, then two or more types of crystal orientations are observed for all of these single crystal planes. The method for surface analysis of polycrystalline diamond using a scanning electron microscope or the like is the method described in the examples.

[0026] The polycrystalline diamond layer preferably has a grain size ratio of the

[0111] plane to the

[0110] plane (

[0111] plane /

[0110] plane) of 2 times or less, and more preferably 1 to 2 times.

[0027] The thickness of the polycrystalline diamond is not particularly limited, but is, for example, 5 μm or more, preferably about 10 to 50 μm, more preferably about 15 to 40 μm, and even more preferably about 20 to 30 μm. The polycrystalline diamond is preferably a polycrystalline diamond layer formed in layers on the surface of a single crystal diamond.

[0028] A method for producing the diamond bond of the present invention by forming polycrystalline diamond on the surface of single-crystal diamond using the thermal filament CVD method includes, for example, the following steps. Process (0): A process of attaching diamond particles to the surface of a single-crystal diamond. Step (1): A process of introducing a carrier gas containing a carbon source and, if necessary, an impurity source (e.g., a boron source, a phosphorus source, etc.) into a vacuum vessel in which a single-crystal diamond with diamond particles attached is placed. Step (2): A film deposition process in which a carrier gas containing a carbon source is heated with a filament to deposit polycrystalline diamond onto at least a portion of the surface of a single-crystal diamond.

[0029] In the method for manufacturing a diamond bond of the present invention, it is important to perform step (0) of attaching diamond particles to the surface of a single-crystal diamond before forming polycrystalline diamond on the surface of the single-crystal diamond by the thermal filament CVD method (specifically, steps (1) and (2) above). That is, the method for manufacturing a diamond bond of the present invention preferably comprises the steps of attaching diamond particles to the surface of a single-crystal diamond and forming polycrystalline diamond on the surface of the single-crystal diamond to which the diamond particles are attached by the thermal filament CVD method. This results in the formation of a uniform polycrystalline diamond in which the influence of the crystal orientation of the single-crystal diamond surface is particularly suitably reduced.

[0030] The step (0) of attaching diamond particles to the surface of a single-crystal diamond can be carried out, for example, by immersing the single-crystal diamond in a solution containing diamond particles. Examples of a solution containing diamond particles include a solution in which diamond abrasive grains with random crystal orientations of about 1 μm or less in size are dispersed in alcohol or the like. The immersion time is typically 0.1 to 3 hours. The temperature of the diamond solution is typically 10 to 40°C. After immersion, the diamond solution is dried on the surface of the single-crystal diamond to obtain a single-crystal diamond with diamond particles attached to its surface. The particle size of the diamond particles is not limited to about 1 μm or less; any particle size within the range permitted by the desired processing accuracy is acceptable. Examples of diamond particles include nanodiamond particles (diamond particles with a particle size of about 10 nm or less) and microdiamond particles (diamond particles with a particle size of about 100 nm to 1000 nm).

[0031] By attaching diamond particles to the surface of a single-crystal diamond, the crystal orientations of the single-crystal diamond surface, which have various plane orientations, become random. As a result, polycrystalline diamond bonded to the single-crystal diamond surface by covalent bonds is formed uniformly and strongly, regardless of the plane orientation. Therefore, the manufacturing of the diamond bond of the present invention involves attaching diamond particles to the surface of a single-crystal diamond and then growing polycrystalline diamond. In the diamond bond of the present invention, the uniform polycrystalline diamond formed in this way has the following characteristics: as described above, surface analysis using a scanning electron microscope shows that the grain size is less than 10 μm, and in the inverse pole figure orientation map using electron backscatter diffraction, two or more types of crystal orientations can be observed on all single-crystal planes, resulting in a polycrystalline diamond film.

[0032] Next, in step (1) of introducing a carrier gas containing a carbon source and, if necessary, an impurity source (e.g., a boron source, a phosphorus source, etc.) into a vacuum vessel on which diamond particles are attached and a single-crystal diamond is arranged, the metal constituting the filament placed in the vacuum vessel is not particularly limited as long as it can form a filament. Specific examples of metal elements include, as mentioned above, tungsten, tantalum, rhenium, ruthenium, etc., with tungsten being preferred among these. The metal element may be used alone or in combination of two or more types.

[0033] In step (1), after creating a vacuum in the vacuum chamber, a carrier gas containing a carbon source is introduced. The carbon source is not particularly limited as long as it can form diamond, for example, methane. The carbon source may be used alone or in combination of two or more types. If boron is used as an impurity for doping, the boron source is not particularly limited as long as it can dopage the diamond as boron and maintain the diamond's crystalline structure, for example, trimethylboron and diborane are preferred. The impurity source may be used alone or in combination of two or more types.

[0034] The carrier gas is not particularly limited, and for example, hydrogen gas can be used. The concentration of the carbon source in the carrier gas containing the carbon source is preferably about 0.5 to 5.0 volume%, more preferably about 1.0 to 3.0 volume%.

[0035] Furthermore, when impurities are to be added to polycrystalline diamond, the concentration of the impurity source relative to the carbon source in the carrier gas should be set appropriately according to the concentration of the impurity to be added to the polycrystalline diamond. For example, when adding boron as an impurity, the concentration of boron in the polycrystalline diamond should be 1 × 10⁻⁶. 18 atoms / cm 3 ~1 × 10 21 atoms / cm 3In this case, the concentration of the boron source relative to the carbon source in the carrier gas is preferably 100 ppm or more, more preferably about 1000 to 20000 ppm, and even more preferably about 5000 to 10000 ppm.

[0036] In step (2), a film deposition process is performed in which a carrier gas is heated with a filament to deposit polycrystalline diamond onto a semiconductor substrate. The heating temperature of the filament can be set appropriately according to the type of metal element that makes up the filament used and the concentration of metal elements and impurities contained in the polycrystalline diamond, preferably around 2000 to 2400°C, and more preferably around 2000 to 2200°C.

[0037] The total pressure inside the vacuum chamber in step (2) is not particularly limited, but for example, it can be about 10 to 100 Torr, more preferably about 10 to 80 Torr.

[0038] The temperature of the single-crystal diamond in step (2) is not particularly limited, but for example, it can be about 700 to 1100°C, more preferably about 700 to 900°C.

[0039] The film formation time in step (2) can be appropriately selected according to the desired thickness, etc., and is usually around 3 to 50 hours. [Examples]

[0040] The present invention will be described in detail below with reference to examples and comparative examples. However, the present invention is not limited to the examples.

[0041] <Example 1> As a substrate, a single-crystal diamond substrate synthesized by a high-temperature, high-pressure method was prepared. The surface of the single-crystal diamond was prepared with multiple plane orientations, such as the

[0100] plane, the

[0111] plane, and the

[0110] plane.

[0042] In addition, a solution containing diamond particles was prepared. 3 g of diamond particles with a particle size of approximately 1 μm or less was added to 200 mL of isopropyl alcohol and treated in an ultrasonic cleaner for 30 minutes.

[0043] Next, at room temperature (25°C), the substrate (single-crystal diamond) was immersed in the diamond solution and subjected to ultrasonic treatment for 30 minutes to deposit nanodiamonds onto the surface of the substrate. Then, the substrate with nanodiamonds attached to its surface was placed in a thermal filament CVD apparatus. The distance between the filament (tungsten purity 99.95%) and the substrate surface was set to 10 mm, and polycrystalline diamond was grown for 10 hours under conditions of a hydrogen flow rate of 1000 sccm, methane concentration of 3%, trimethylboron concentration of 665 ppm, and a filament temperature of approximately 2500°C during crystal growth, thereby producing a diamond composite in which polycrystalline diamond was formed on the surface of a substrate made of single-crystal diamond. The thickness of the polycrystalline diamond in the obtained diamond composite was 5 μm.

[0044] <Reference example 1> A diamond bonded body (single-crystal diamond substrate) was manufactured in the same manner as in Example 1, except that diamond particles were not attached to the surface of the substrate.

[0045] [Observation of crystal growth for each face orientation] To observe crystal growth for each plane orientation, substrates were prepared with the

[0111] ,

[0110] , and

[0100] planes of single-crystal diamond as the surface. Images obtained by scanning electron microscopy (SEM) of the polycrystalline diamond formed on each substrate, with and without nanodiamond attachment, are shown in Figure 1 (with nanodiamond attachment) and Figure 2 (without nanodiamond attachment). The surface of each substrate was observed after hot mixed acid treatment (a process in which the substrate was boiled and washed in a mixture of sulfuric acid and nitric acid at 250°C to 450°C). Figures 1 and 2 show SEM images (10,000x magnification) of the polycrystalline diamond surface formed on the

[0111] ,

[0110] , and

[0100] planes, respectively. As shown in Figure 1, when nanodiamonds are attached to the surface of the substrate, the uniformity of the crystal growth of polycrystalline diamond is very high, and uniform polycrystalline diamond is formed. On the other hand, as shown in Figure 2, when nanodiamonds are not attached to the surface of the substrate, although polycrystalline diamond is formed, the morphology (grain size, crystal shape) after crystal growth differs for each surface orientation.

[0046] [Surface observation of polycrystalline diamond using a scanning electron microscope (SEM)] Surface observation of the polycrystalline diamond in the diamond composites obtained in Example 1 and Reference Example 1 was performed using a scanning electron microscope (SEM). In Example 1, as shown in Figure 1, the grain size was approximately 0.1 to 1 μm, and at least two random crystal orientations were observed on all single crystal planes: the

[0111] plane, the

[0110] plane, and the

[0100] plane. In Reference Example 1, as shown in Figure 2, the grain size was approximately 0.1 to 1 μm, and random crystal orientations were observed. In the polycrystalline diamond of the diamond composite in Reference Example 1, at least two random crystal orientations were observed on the

[0111] plane and the

[0110] plane, but only one crystal orientation (the

[0100] direction) was observed on the

[0100] plane. Furthermore, in the polycrystalline diamond layer of Example 1, the ratio of the crystal grain size of the

[0111] plane to the

[0110] plane was 2 times or less, indicating a uniform crystal grain size with little variation in crystal grain size.

[0047] Furthermore, using electron beam backscatter diffraction (EBSD), inverse pole figure orientation (IPF) maps (Figure 3) were performed on samples where polycrystalline diamond was grown on the

[0100] and

[0111] planes of the substrate, similar to Figure 1. The results confirmed that both surfaces had at least two random orientations. Moreover, SEM observations clearly showed that samples where polycrystalline diamond was grown on the

[0110] plane of the substrate also had at least two random orientations, similar to the

[0111] and

[0110] planes.

Claims

1. A bonded material of single-crystal diamond and polycrystalline diamond, At the bonding surface between the single-crystal diamond and the polycrystalline diamond, the surface of the single-crystal diamond has multiple surface orientations. Surface analysis of the aforementioned polycrystalline diamond using a scanning electron microscope revealed that the grain size is less than 10 μm, and that two or more crystal orientations were observed on all single crystal planes using an inverse pole figure orientation map based on electron backscatter diffraction. At the bonding surface between the single-crystal diamond and the polycrystalline diamond, the surface of the single-crystal diamond includes at least one of the [100] plane, [111] plane, and [110] plane, The aforementioned polycrystalline diamond layer is a diamond bond in which the ratio of the grain size of the [111] plane to the grain size of the [110] plane is 2 times or less.

2. The diamond composite according to claim 1, wherein at least one of the single-crystal diamond and the polycrystalline diamond contains a metallic element.

3. The diamond composite according to claim 1 or 2, wherein at least one of the single-crystal diamond and the polycrystalline diamond contains an impurity.

4. The diamond bond according to claim 3, wherein the impurity is at least one selected from the group consisting of boron, phosphorus, and nitrogen.

5. An electronic device, optical element, or sliding member comprising a diamond bond according to any one of claims 1 to 4.

6. A method for manufacturing a diamond bond according to any one of claims 1 to 4, A step of attaching diamond particles to the surface of the single-crystal diamond, A step of forming polycrystalline diamond on the surface of the single-crystal diamond on which the diamond particles are attached by a thermal filament CVD method, A method for manufacturing a diamond bond, comprising the features described above.

Images