JPH06262521A - Grinding wheel and its manufacture - Google Patents

Abstract

PURPOSE:To remarkably increases the holding force, wear resistance, and durability of diamond abrasive grains in grinding by putting diamond abrasive grains in recesses provided on a first substrate, making diamond crystal abrasive grains growth, and reversing them on a second substrate and jointing or sticking them each other. CONSTITUTION:In a grinding wheel, natural or artificial diamond particles 34 are put beforehand in recesses 33 provided on a first substrate 31 at a specified size, form, interval, and density. After that, homopytaxial growth is made with the diamond particles 34 used as nucleus by gaseous phase synthesizing method to grow them as diamond crystal abrasive grains 35. Then the diamond crystal abrasive grains 35 are reversed on a second substrate 38 as a substrate for grinding wheel, and jointed or stuck. Thus the holding force, wear resistance is grinding, and durability of the diamond abrasive grains 35 are remarkably increased. This is because the top end form of the reversed diamond crystal abrasive grains 35 is uniform, and also adhesion to the substrate 38 is improved by the joining or adhexing.

Description

Detailed Description of the Invention

[0001]

The present invention relates to glass, ceramics,
The present invention relates to a grinding wheel for precisely grinding a hard and brittle material such as a crystalline material, using a vapor-phase synthetic diamond crystal as an abrasive grain, and a method for producing the grinding wheel.

[0002]

2. Description of the Related Art Conventionally, a grinding wheel using a vapor-phase synthetic diamond crystal as abrasive grains is disclosed in JP-A-2-279278 and JP-A-3-279278.
As disclosed in Japanese Patent Laid-Open No.-208560, vapor-phase synthetic diamond is grown in the form of single crystal particles or a polycrystalline film,
In some cases, a metal layer such as plating is provided around the diamond abrasive grains to hold the abrasive grains to form a grinding stone.

[0003]

In a conventional grinding wheel using a vapor-phase synthetic diamond crystal as an abrasive grain, a diamond crystal having good crystallinity is formed as the abrasive grain and used as the grinding wheel. However, when a diamond crystal having good crystallinity is grown, crystals having various orientations grow on the substrate due to the non-uniformity of the substrate surface state. Therefore, the force applied to each abrasive grain is different due to the difference in the tip shape of diamond acting as abrasive grains, the difference in hardness wear due to the difference in crystal orientation of the action part, and the difference in the abrasive grain height due to the difference in tip shape. Due to the variation, a phenomenon occurs in which only a part of a large number of grown abrasive grains act as abrasive grains. Further, in the grinding wheels disclosed in JP-A-2-279278 and JP-A-3-208560, the diamond crystals are formed directly on the base body to be the grindstone or by providing an intermediate layer. Since the adhesiveness is not sufficient, the crystal grains come off during grinding. Therefore, when hard, brittle materials such as glass, ceramics, and crystalline materials are processed using such a grinding wheel, an unreasonable force is applied to some of the abrasive grains, causing brittle fracture of the work piece, and surface roughness. And problems such as cracking and cracking occur.

The present invention has been made in view of the above problems, and by disposing abrasive grains having a uniform tip shape on a substrate with high adhesion strength, a hard and brittle material such as glass or semiconductor can be provided with a good surface roughness. An object of the present invention is to provide a grinding whetstone for grinding with a blade.

[0005]

The grinding wheel of the present invention has a structure in which natural or artificial diamond grains are placed in recesses which are provided in advance on the first substrate with a predetermined size, shape, interval and density. A feature that homoepitaxial growth is performed by using the diamond grains as nuclei by a vapor phase synthesis method to grow diamond crystal abrasive grains, and the diamond crystal abrasive grains are inverted and bonded or bonded to a second substrate that is a base of a grinding wheel. And

Further, the grinding wheel of the present invention is characterized in that a filling layer for firmly fixing the abrasive grains is provided between the diamond crystal abrasive grains.

[0007]

The function of the present invention will be described below together with the findings obtained in making the present invention.

In view of the problems of the conventional grinding wheel, the present inventor has carried out detailed experiments on a method for fixing diamond abrasive grains, and as a result, the holding power of the diamond abrasive grains, the abrasion resistance during grinding, and the durability have been improved. I was able to clarify the involvement of.

That is, recesses corresponding to the size, shape, interval, and density of abrasive grains capable of obtaining high grinding performance are formed on the first substrate, and natural or artificial diamond grains are placed in the recesses to carry out vapor phase synthesis. By using the diamond grains as nuclei to homoepitaxially grow diamond to form diamond crystal abrasive grains, which are used as the base of the grinding wheel.
After inverting, bonding or adhering to the substrate of, the filling layer is provided between the diamond crystal abrasive grains and firmly fixed,
It has been found that the holding power of diamond abrasive grains, wear resistance during grinding, and durability are significantly improved.

It is considered that the reason is that the inverted diamond crystal has a uniform tip shape in all the crystal grains and that the adhesion or adhesion to the substrate is improved by bonding or adhering the diamond crystal. That is,
This is because the diamond crystals that have been homoepitaxially grown by vapor phase synthesis with the diamond grains arranged in the recesses as the nuclei are inverted, so that a diamond grinding wheel having an ideal shape as the abrasive grains of the grinding wheel and the degree of tip alignment can be obtained. Also, since the diamond crystal abrasive grains are fixed to the substrate by bonding or adhesion, the adhesion strength with the substrate is also improved.

The diamond crystal abrasive grains described in the present invention are those which can be confirmed as diamond crystals by an analysis method such as X-ray diffraction, electron beam diffraction or Raman spectroscopy. Specifically, in the Raman spectroscopy has a sharp peak of diamond around 1333 cm ^-1, as shown for example in FIG. 1, 1360 cm ^-1 and 1550c
It has almost no broad peak due to amorphous carbon near m ^-1 . The diamond crystal in the present invention is homoepitaxially grown on a diamond single crystal grain that is naturally or artificially synthesized. Further, as single crystal grains serving as nuclei, alumina, cB
N etc. can also be used.

The second base used as the base of the grinding wheel in the present invention is an oxide ceramics such as alumina or zirconia, a carbide such as silicon carbide, silicon nitride, titanium carbide, titanium nitride or tungsten carbide, or a nitride. It is possible to use ceramics such as WC-based cemented carbide, metals such as molybdenum, tungsten and tantalum. The shape of the second base can be arbitrarily determined depending on the use and the material and shape of the ground product. For example, when grinding glass having a spherical lens shape, the second base has a curved shape according to the radius of curvature of the spherical lens. , Forming diamond crystals on the curved surface.

FIG. 2 shows a schematic sectional view of an example of the grinding wheel 1 of the present invention. In the figure, 2 is a second base, which is a grindstone base, and 3
Is a diamond crystal, 4 is an adhesive layer, and 5 is a filling layer for fixing the diamond crystal.

The method of manufacturing the grinding wheel of the present invention will be described below.

First, a concave portion corresponding to the size, shape, interval, and density of abrasive grains capable of obtaining high grinding performance is formed on the first substrate, and natural or artificial diamond grains are arranged in the concave portion, and vapor phase synthesis is performed. Thus, diamond is homoepitaxially grown on the diamond grains to form diamond crystal abrasive grains.

The first substrate used for homoepitaxial growth of diamond crystals is a material that can be etched by ordinary photolithography and is stable at the diamond formation temperature, and at the same time, it can be polished or wet etched. It is desirable that the material be possible. Such materials include Si, Ta,
Mo, W, WC, SiC, SiO ₂ , Al ₂ O ₃ , Si ₃ N
₄ etc.

The recess is formed by chemical etching or dry etching using a general photolithography technique. Alternatively, mechanical processing may be used. The shape of the recess is not limited as long as diamond grains can be arranged and the homoepitaxial growth can be sufficiently performed by vapor phase synthesis. That is, it is preferable that the cross-sectional area (area of the opening) of the recess on the substrate surface side is 50 μm ² or more, and the interval between the recesses is 10 μm or more. Further, the depth is preferably 50% or more of the outer dimension of the formed diamond crystal. The abrasive grain interval must be sufficiently larger than the diamond crystal abrasive grain size to be formed.

The particles used as nuclei for homoepitaxial growth have a size that can be placed in the recesses, and preferably one that can be placed in each recess is selected.

The vapor phase synthesis method of diamond crystals used in the present invention is a hot filament CVD method, a microwave plasma CVD method, a direct current plasma CVD method, a high frequency plasma CV.
D method, magnetic field microwave plasma CVD method, combustion flame method and the like can be mentioned. At this time, the source gas is a carbon source such as methane, ethane, propane, butane, ethylene, hydrocarbon gas such as acetylene, CO, CO ₂ , CCl ₄ , C
HCl ₃ , CH ₂ Cl ₂ , CH ₃ Cl, CF ₄ , CClF ₃ ,
Compounds of carbon and oxygen such as CHF ₃ and the like, chlorine and fluorine, and organic compounds such as methanol, ethanol, acetone and acetic acid are used, and hydrogen, oxygen, halogen gas,
A rare gas or the like may be appropriately mixed.

The conditions for forming the diamond crystal differ depending on the synthesis method. For example, when a hydrogen-methane based source gas is used by the microwave plasma CVD method, the methane gas concentration is 0.3-5% and the substrate temperature is 600- 900
It is desirable that the temperature be C, the pressure be 1.33 to 26.6 kPa, and the total gas flow rate be 100 to 1000 ml / min.

In the present invention, in order to bond the formed diamond crystal to the second base body which is the base body of the grinding wheel,
After the diamond crystal formed surface of the first substrate and the second substrate are joined, the first substrate is removed by polishing or etching. As a bonding material used for bonding diamond crystals, it has good wettability with diamond,
It is preferable that the grinding wheel can guarantee sufficient mechanical strength and geometrical dimensional accuracy under the usage conditions. Examples of such materials include Ti, Zr, Hf, V, Nb, Ta, Cr,
Mo, W, Fe, Ru, Os, Co, Rh, Ir, N
i, Pd, Pt, Cu, Ag, Au, Si, Ge, S
Metals such as n and Pb, or compounds, mixtures and alloys composed of one or a combination of two or more of these are preferable, and as the alloy, Ag-Cu, Ag-Sn, Ti-
Ag, Ti-Cu, Ti-Co, Ti-Ni, Au-N
Alloys such as b and Au-Ta are preferable. Further, it is preferable that the second substrate to be bonded has good adhesion and has sufficient strength by bonding, and at the same time has sufficient bonding strength under grinding conditions. In particular, it is preferable that the bonding material and the second substrate have similar thermal expansion coefficients. For example, when WC is used as the second substrate, Ti, Ta, Ni or the like is suitable.

As a method of bonding, a layer of the bonding material is formed on the surface of the first substrate on which the diamond crystals are formed, and this and the second substrate are fitted and heated to bond them.
Alternatively, either of the methods of forming a layer of a bonding material on the second base, fitting and heating and bonding may be used. However, when the bonding material layer is formed on the second base, bonding is performed. It is preferable that the materials are of the same kind.

The bonding material is formed by vacuum deposition, sputtering, ion plating, CVD method, plating method or the like. The layer thickness of the bonding material may be such that the unevenness of the diamond crystal can be flattened, sufficient adhesion can be obtained, and the adhesion does not decrease due to the internal stress of the film. Normal,
It is in the range of 1 to 10 μm, preferably 2 to 4 μm. It should be noted that, at the time of bonding, it is necessary to make adjustment so that the tip positions of the diamond crystals after reversal are aligned.

Further, after inverting and joining the diamond crystals, a metal or the like is filled between the diamond crystals by a plating treatment to firmly fix the diamond crystals. The plating treatment may be either electrolytic plating or electroless plating. Further, as the plating material, nickel, cobalt, chromium, silver and alloys thereof can be used. In addition to metal, resin or rubber adhesive can be used.

Further, the diamond crystals homoepitaxially grown in the above-mentioned recesses may be fixed by a resin or a rubber elastic body, and then reversely adhered to the second base body which is the base body of the grinding wheel to form the grindstone. The resin or rubber elastic body used for fixing the diamond crystals is not particularly limited, but examples of the resin include epoxy resin, PMMA resin, nylon resin, urethane resin, and polycarbon resin. Resin, polystyrene-based resin, fluororesin, polyethylene-based resin, polypropylene-based resin, polyvinyl chloride-based resin, acetate-based resin, polyamide-based resin, polyester-based resin, etc. As rubber elastic body, silicone rubber, natural rubber, neoprene rubber , Urethane rubber and the like. In order to make the thickness of the resin or rubber elastic body uniform, a method such as applying and curing the resin or rubber elastic body by a spin coating method may be used. The hardened resin or rubber elastic body is separated from the first substrate together with the diamond crystal. At this time, in order to facilitate the peeling, it is desirable to apply a release agent to the substrate in advance. Further, the shape of the first base body forming the concave portion does not need to be fitted to the second base body which is the base body of the grinding wheel, and thus may be a flat plate shape. In this case, the fixed layer of resin or rubber elastic body after reversal and transfer is also flat (sheet-shaped). This sheet is a member that fits into the grinding wheel, and is arranged so that the abrasive grains are on the fitting member side and pressed against the grinding wheel. At this time, an adhesive layer for fixing the sheet is provided on the side of the grinding wheel, and the grinding wheel base and the fitting member are adjusted and bonded so that the tip positions of the respective abrasive particles are aligned, and the particles are fixed according to the shape of the grinding wheel. A layer is formed on the grinding wheel surface. In addition,
When the diamond crystal formed in the recess is easily transferred by reverse transfer from the first substrate, this first substrate can be repeatedly used as a mother.

[0026]

EXAMPLES Next, the present invention will be specifically described based on examples, but the present invention is not limited to the following examples.

Example 1 A manufacturing process of a grinding wheel in this example will be described with reference to FIG. First, a Si (100) substrate 31 (40 mmφ) is formed as a first substrate having a shape that fits with a grinding wheel.
X8 ^t , convex shape with curvature R = 35)
1 by photolithography (optical drawing method) with a line width of 50 μm using an Al film 32 having a thickness of 0.1 μm as a mask,
A grid-like pattern having a pitch of 100 μm was formed (FIG. 3A). This substrate is set in a microwave plasma etching apparatus, and isotropic etching is performed at a gas pressure of 12.5 Pa and a microwave output of 200 W using CF ₄ containing 17% of O ₂ as an etching gas. A concave portion 33 having a predetermined shape was formed on the surface of the substrate (see FIG. 3).
(B)).

Next, after removing the Al film on the first substrate, the diamond abrasive grains 34 having a grain size of 70 μm are dispersed on the first substrate, and the first substrate is rotated at several rpm to several hundred rpm. The diamond abrasive grains were placed only in the recesses (FIG. 3 (c)).

The first substrate having the diamond abrasive grains thus arranged in the recesses was placed in the apparatus shown in FIG. 4 to perform homoepitaxial growth of diamond (FIG. 3 (d)). FIG. 4 is a schematic view of an apparatus by the hot filament CVD method for performing homoepitaxial growth of diamond.
Reference numeral 41 is a quartz reaction tube, 42 is an electric furnace, 43 is a tantalum filament, 44 is the first substrate, and 45 is a raw material gas introduction port, which is connected to a gas cylinder, a gas flow rate regulator, and a valve (not shown). A gas exhaust port 46 is connected to a mechanical booster pump, a rotary pump, and a valve (not shown). The substrate 44 was put into the quartz reaction tube 41, and after being evacuated by a vacuum pump (not shown), methane 4 ml / min and hydrogen 996 ml / mi were supplied from a gas cylinder (not shown).
the quartz reaction tube 41 through the raw material gas inlet 45 at a flow rate of n.
The raw material gas is introduced into the reaction tube, the pressure inside the reaction tube is adjusted to 6.60 kPa by a pressure adjusting valve (not shown), and the electric furnace 42
To 900 ° C. in the reaction tube, and the filament 43
Was heated to 2000 ° C. to form diamond. The processing time at this time was 20 hours.

Observation of the surface of the first substrate with a scanning electron microscope revealed that diamond crystals 35 having a self-shaped surface with a diameter of about 100 μm were formed in recesses (patterned portions) on the substrate at a pitch of 50 μm ( FIG. 3D).

Next, after the diamond crystal surface was subjected to plasma treatment, the bonding material layer 36 was formed. First, Ti was formed in a thickness of 4 μm by a sputtering method, and further Ni was formed in a thickness of 3 μm on the Ti. Similarly, a Ni layer 37 having a thickness of 10 μm was also formed on the surface of the second base 38, which is the base of the grinding wheel made of WC-based cemented carbide having a shape fitting with the first base.

After fitting both substrates together, in a vacuum 85
Bonding was performed by heating to 0 ° C (Fig. 3
(E)). At this time, the joining was performed by fixing with a uniform force of about 0.15 kg / mm ² for about 3 hours. Further, the fixing was carried out by adjusting so that the gaps between the bases were uniform. Then, the Si substrate was polished to completely remove Si (FIG. 3 (f)). For removing the Si substrate, potassium hydroxide or HNO ₃ : HF: CH ₃ COOH =
Wet etching may be performed with a solution of 5: 3: 3 or the like. After removing Si, the diamond crystal had a shape obtained by inverting the pattern formed by etching on the Si substrate. A nickel plating layer 39 was formed around the diamond crystal grains by electroless plating on the substrate to which the diamond crystal grains were reverse-bonded, and the diamond crystal grains were fixed to complete the grinding wheel (FIG. 3). (G)). At this time, the plating layer 39 was formed such that the tip of the diamond crystal protruded from the surface of the plating layer 39 by 20 μm or more.

Using this grinding wheel, a grinding test was performed on a glass lens having a convex shape of R35 mm to evaluate the grinding performance.

The grinding test was carried out by a known ball-centered vibrating grinder with a grindstone rotation speed of 3000 rpm and a pressure of 1 kg / cm.
The constant pressure processing was performed at ² for 30 seconds. As a result, the surface of the glass lens became a plastic flow surface having a roughness of 0.1 μm Rmax, and the removal amount of the lens was about 20 μm, which was a value equivalent to that of a normal fine grinding pellet. Further, as a result of observing the diamond crystal tip of the grinding wheel after the grinding test with a scanning electron microscope, no wear of the crystal tip was observed.

Example 2 A manufacturing process of a grinding wheel in this example will be described with reference to FIG. First, a Si base 51 (50 mmφ × 50 mm) whose surface is a (100) plane is formed as a first base for forming a recess.
10 ^t , flat plate shape), a line width of 50 μm,
A grid-like pattern with a pitch of 100 μm is formed to a film thickness of 0.1.
It was formed of SiO ₂ 52 of μm (FIG. 5A). This substrate was converted into H ₂ O: (NH ₂ ) ₂ CH ₂ : C ₆ H ₄ (OH) ₂ = 3:
By immersing in a 17: 8 etching solution and performing anisotropic etching, a concave portion 53 having a V-shaped cross section as shown in FIG. 6 was formed on the surface of the substrate (FIG. 5B). The opening of the surface of this recess is □ 100 μm and the depth is 71 μm.
Met.

Next, while leaving the SiO ₂ film on the first substrate, diamond abrasive grains 54 having a grain size of 60 μm were used in Example 1.
In the same manner as above, it was arranged only in the concave portion (FIG. 5 (c)).

The first substrate having the diamond abrasive grains thus arranged in the recesses was placed in the apparatus shown in FIG. 7 to perform homoepitaxial growth of diamond (FIG. 5 (d)). FIG. 7 is a schematic diagram of a microwave plasma CVD apparatus. In the figure, 71 is a quartz reaction tube, 72 is a substrate, 73 is a source gas introduction system, 74 is a microwave power source, 75 is a microwave waveguide, and 76 is a vacuum exhaust system. The raw material gas was introduced into the quartz reaction tube 71 from the raw material gas introduction system 73 at a flow rate of 5 ml / min of methane and 700 ml / min of hydrogen, and the pressure inside the reaction tube was adjusted to 10.60 kPa by a pressure adjusting valve (not shown). , Microwave output 5 from microwave power supply 74
Diamond formation was performed at kW and a substrate temperature of 850 ° C.
The processing time at this time was 4 hours.

Observation of the surface of the first substrate with a scanning electron microscope revealed that diamond crystals 55 having a self-shaped surface with a diameter of about 120 μm were formed in recesses on the substrate at a pitch of 50 μm (FIG. 5 (e)). ).

Next, after plasma-treating the diamond crystal surface, a polypropylene resin ("Polypro J-750H" (registered trademark) manufactured by Idemitsu Petrochemical Co., Ltd.) was formed on this substrate to a thickness of 500 μm. And solidified (FIG. 5 (f)). From the Si substrate on which the polypropylene-based resin layer 56 was formed, the Si substrate was removed to obtain a polypropylene resin sheet in which diamond crystals were reversely transferred (FIG. 5).
(G)).

Next, after the bonded surface of the sheet is subjected to plasma treatment, a base 57 for a grinding wheel and a diamond crystal 55 are provided.
Was adhered so as to be the surface of the grinding wheel, to obtain a grinding wheel (FIG. 5 (i)). Alumina (Al ₂ O ₃ ) having a convex shape of R20 mm is used as the base 57, and an adhesive containing a filler mainly composed of a bisphenol A-based epoxy resin is used for adhesion (for example, manufactured by Ciba Geigy, “
Araldite; AW136NH "(registered trademark) 58 was used. At this time, pressure welding was performed using a resin base 59 having a shape that can be fitted to the grinding wheel (FIG. 5).
(H)).

Using this grinding wheel, a grinding test of a glass lens having an R20 mm convex shape was carried out in the same manner as in Example 1 to evaluate the grinding performance. As a result, the surface of the glass lens becomes a plastic flow surface with a roughness of 0.1 μm Rmax,
The removal amount of the lens was about 20 μm, which was a value equivalent to that of a normal fine grinding pellet. Further, as a result of observing the diamond crystal tip of the grinding wheel after the grinding test with a scanning electron microscope, no wear of the crystal tip was observed.

Example 3 The manufacturing process of the grinding wheel in this example is based on FIG.
And explain. First, as the first substrate for forming the recess
The same Si substrate 81 as in Example 2 is used, and the line width is
Lattice-shaped Al pattern with 50 μm pitch and 80 μm pitch
82 was formed (FIG. 8A). This base 81 is a microphone
Opening 80μm □, deep by microwave plasma etching
A recess 83 having a thickness of 40 μm was formed (FIG. 8B). this
Sometimes CF as etching gas_FourTo O₂Mixed with 17%
Gas pressure 6.7 × 10 ^-1Pa, microwave output
Formed on the surface of the substrate by etching with a force of 200 W
The recess had a trapezoidal cross section as shown in FIG.

Next, while leaving the Al film on the first substrate, diamond abrasive grains 84 having a grain size of 50 μm were placed only in the recesses 83 in the same manner as in Example 1 (FIG. 8 (c)).

Next, homoepitaxial growth of diamond was performed in the same manner as in Example 2 (FIG. 8 (d)). As a result, when observing the surface of the first substrate with a scanning electron microscope, it was found that diamond crystals 85 having a diameter of about 80 μm and having a clear self-shaped surface were formed in the recesses on the substrate at a pitch of 50 μm.

Next, a bisphenol A epoxy resin (Ciba Geigy Co., "Araldite; A
Y103 "(registered trademark) is applied and 80 in an electric furnace
After being dried and solidified at ℃ for 1 hour (Fig. 8 (e)). The Si substrate was removed to obtain an epoxy resin sheet in which diamond crystals were reversely transferred (FIG. 8 (f)).

Then, the sheet was adhered to a base body 87 for a grinding wheel having an adhesive layer on its surface so that the diamond crystals 85 were on the surface of the grinding wheel in the same manner as in Example 2 to obtain a grinding wheel (see FIG. 8 (h)). As the base 87, R2
Alumina (Al ₂ O ₃ ) having a convex shape of 0 mm was used, and the adhesive was an adhesive (for example, “Araldite; AW136NH” (registered trademark) manufactured by Ciba-Geigy).
88 was used. At this time, pressure welding was performed using a resin base 89 having a shape that can be fitted to the grinding wheel (FIG. 8).
(G)).

Using this grinding wheel, the grinding performance was evaluated under the same method and conditions as in Example 1, and the same results as in Example 1 were obtained.

In the above embodiments, only the processing of the spherical lens has been described, but the grinding wheel of the present invention is not limited to such a construction method, and for example, surface grinding, cylindrical grinding, inner surface grinding, aspherical grinding. It can also be applied to processing methods such as.

[0049]

As described above, in the grinding wheel of the present invention, the shape of the tip of the abrasive grains of the diamond crystal is uniform and the adhesion to the wheel base is improved. Compared with a grinding wheel, it has the effect of significantly improving the holding force, wear resistance, and durability of diamond abrasive grains during grinding.

Further, these grinding wheels are excellent as grinding wheels for precisely grinding hard and brittle materials such as glass, ceramics, and crystalline materials.

[Brief description of drawings]

FIG. 1 is a graph showing the measurement results of Raman spectroscopic analysis of diamond crystals.

FIG. 2 is a schematic sectional view showing an example of a diamond grinding wheel of the present invention.

FIG. 3 is a schematic view showing an example of a manufacturing process of the grinding wheel of the present invention.

FIG. 4 is a schematic diagram of a diamond forming apparatus by a hot filament CVD method.

FIG. 5 is a schematic view showing an example of a manufacturing process of the grinding wheel of the present invention.

FIG. 6 is a schematic cross-sectional view showing an example of a recessed shape formed in the first base body.

FIG. 7 is a schematic diagram of a microwave plasma CVD apparatus used for diamond formation in Examples.

FIG. 8 is a schematic view showing an example of a manufacturing process of the grinding wheel of the present invention.

FIG. 9 is a schematic cross-sectional view showing an example of a concave shape formed in the first base body.

[Explanation of symbols]

 1 Grinding Wheel 2 Grinding Wheel Base (Second Base) 3 Diamond Crystal 4 Bonding Layer 5 Filling Layer 31, 51, 81 First Base 33, 53, 83 Recess

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical indication C23C 16/26 7325-4K C30B 29/04 X 8216-4G

Claims (4)

[Claims] 1. A predetermined size, shape, and
After arranging natural or artificial diamond grains in the recesses provided at intervals and densities, homoepitaxial growth is performed by the vapor phase synthesis method using the diamond grains as nuclei to grow diamond crystal abrasive grains, and the diamond crystal abrasive grains are ground. A grinding wheel characterized by being turned over to a second base, which is the base of the grindstone, and bonded or bonded. 2. The grinding wheel according to claim 1, wherein a filling layer for firmly fixing the abrasive grains is provided between the diamond crystal abrasive grains. 3. A natural or artificial diamond grain is placed in a recess previously formed on the first substrate with a predetermined size, shape, interval and density, and the diamond grain is used as a nucleus by a vapor phase synthesis method. A method for producing a grinding wheel, wherein homoepitaxial growth is performed to grow diamond crystal abrasive particles, and the diamond crystal abrasive particles are inverted and bonded or bonded to a second base material which is a base material of the grinding wheel. 4. The method for producing a grinding wheel according to claim 3, wherein a filling layer for firmly fixing the abrasive grains is provided between the diamond crystal abrasive grains.