JP7098231B2 - Electroplated whetstone - Google Patents

Description

The present invention relates to an electrodeposition grindstone including a grindstone portion in which abrasive grains are fixed by a plating layer.

Cutting devices are widely used for cutting various workpieces. For example, a cutting process for dividing a semiconductor wafer into a plurality of device chips is performed using a cutting device. In addition, a glass epoxy board formed by impregnating glass fiber with an epoxy resin is used for the LED (Light Emitting Diode) package, and the glass epoxy board is also cut when the device package is obtained by dividing the glass epoxy board. Cutting is performed by the device.

The cutting process is performed using an annular grindstone (cutting blade) mounted on the tip of a spindle provided in the cutting device. This grindstone is formed, for example, by fixing abrasive grains made of diamond or the like with a plating layer containing nickel or the like. In Patent Document 1, an electrolytically-worn substrate is immersed in an electrolytic solution such as nickel sulfate mixed with abrasive grains such as diamond, and a plating layer containing the abrasive grains is grown on the substrate to manufacture an annular grindstone. The method is disclosed.

When the spindle of the cutting device is rotated and the annular grindstone is rotated to cut into the workpiece, the abrasive grains exposed from the plating layer of the grindstone come into contact with the workpiece and the workpiece is cut. Then, when the cutting process is continued, the plating layer is worn and the exposed abrasive grains fall off, and new abrasive grains are exposed from the plating layer. This action is called a self-generated blade, and the self-generated blade maintains the cutting function of the grindstone.

Japanese Unexamined Patent Publication No. 2000-87282

In a grindstone in which the abrasive grains are fixed by a plating layer containing nickel, the abrasive grains are relatively strongly fixed to the plating layer. Therefore, even if the workpiece is cut, the abrasive grains are less likely to fall off from the plating layer, and spontaneous blade formation is less likely to occur. If the self-generated blade is not generated appropriately, for example, cutting chips may accumulate between the exposed abrasive grains and the cutting resistance may increase (clogging), or the exposed abrasive grains may be smoothed by wear and the sharpness of the grindstone may decrease. Phenomena such as (blinding) occur. When cutting is performed with a grindstone in such a state, processing defects such as chipping, which is called chipping, occur in the workpiece.

Further, in particular, in the cutting process of a material called a difficult-to-cut material, which is difficult to cut, such as glass, ceramics, glass epoxy resin, and a composite material of a resin and an electrode, spontaneous blade generation is unlikely to occur. Therefore, if a grindstone in which the abrasive grains are fixed with a plating layer containing nickel is used, there is a problem that it becomes more difficult to cut a difficult-to-cut material that is originally difficult to cut.

The present invention has been made in view of such a problem, and an object of the present invention is to provide an electrodeposition grindstone capable of suppressing the occurrence of processing defects.

According to one aspect of the present invention, a grindstone portion in which abrasive grains are fixed by a plating layer containing nickel is provided, and the grindstone portion contains 2.2% by volume or more and 15.0% by volume or less of talc of the grindstone portion. The contained electrodeposition grindstone is provided.

Further, in one aspect of the present invention, the grindstone portion may contain talc of 2.2% by volume or more and 6.2% by volume or less of the grindstone portion. Further, in one aspect of the present invention, the average particle size of talc contained in the grindstone portion may be 0.6 μm or more and 10.0 μm or less.

Further, in one aspect of the present invention, the electrodeposited grindstone may be composed of only the annular grindstone portion. Further, in one aspect of the present invention, the electrodeposited grindstone may be composed of an annular base having a grip portion and the grindstone portion formed on the outer edge portion of the base.

The electrodeposited grindstone according to one aspect of the present invention includes a grindstone portion containing talc, which is a material having a hardness lower than that of nickel and having lubricity. By performing cutting using this electrodeposition grindstone, the self-generated blade of the electrodeposition grindstone is promoted, the friction between the electrodeposition grindstone and the workpiece is reduced, and the occurrence of machining defects can be suppressed. It will be possible.

FIG. 1A is a perspective view showing a configuration example of an electrodeposition grindstone including a grindstone portion, and FIG. 1B is a perspective view showing a configuration example of an electrodeposition grindstone including a base and a grindstone portion. It is sectional drawing which shows typically the structural example of the manufacturing apparatus used for manufacturing a washer type electrodeposition grindstone. FIG. 3A is a cross-sectional view showing a state in which the grindstone portion is formed on the surface of the base, and FIG. 3B is a cross-sectional view showing how the grindstone portion is peeled off from the base. It is sectional drawing which shows schematically the structural example of the manufacturing apparatus used for manufacturing a hub type electrodeposition grindstone. FIG. 5A is a cross-sectional view showing a state in which the grindstone portion is formed on the surface of the base, and FIG. 5B is a cross-sectional view showing a state in which a part of the grindstone portion covered with the base is exposed. It is a figure. It is a graph which shows the relationship between the amount of talc contained in the grindstone part of an electrodeposition grindstone, and the ratio of the maximum chipping size. It is a graph which shows the relationship between the amount of talc contained in the grindstone part of an electrodeposition grindstone, and the ratio of the elastic modulus of an electrodeposition grindstone.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The present embodiment relates to a grindstone (electroplated grindstone) formed by electrodeposition. 1 (A) and 1 (B) show a configuration example of an electrodeposition grindstone that can be used in this embodiment.

FIG. 1A is a perspective view showing a configuration example of an electrodeposited grindstone 1 including a grindstone portion 3. The electrodeposition grindstone 1 is composed of only an annular grindstone portion 3 having a through hole 3a in the central portion, and the entire electrodeposition grindstone 1 is a cutting edge formed by electrodeposition. The grindstone portion 3 is formed by fixing abrasive grains such as diamond with a plating layer containing nickel, for example. The electrodeposited grindstone 1 composed of the annular grindstone portion 3 is called a washer type.

FIG. 1B is a perspective view showing a configuration example of an electrodeposited grindstone 5 including a base 7 and a grindstone portion 9. The electrodeposition grindstone 5 is composed of an annular base 7 having a through hole 7a in the central portion and a grindstone portion 9 formed by electrodeposition on the outer edge portion of the base 7. The grindstone portion 9 is formed by fixing abrasive grains such as diamond with a plating layer containing nickel, for example. The electrodeposited grindstone 5 in which the grindstone portion 9 is electrodeposited on the outer edge portion of the base 7 is called a hub type.

Further, the base 7 has an annular grip portion 7b protruding in the width direction at the center thereof. When performing cutting using a cutting device, the user (operator) of the cutting device can attach the electrodeposited grindstone 5 to the cutting device by holding the grip portion 7b.

The electrodeposition grindstones 1 and 5 are attached to the tip of a spindle provided in the cutting device. When the spindle is rotated in this state, the electrodeposited grindstones 1 and 5 rotate with the axis of the spindle as the axis of rotation. Then, by cutting the electrodeposited grindstones 1 and 5 into the workpiece in a rotated state, the workpiece is cut.

There are no restrictions on the material of the workpiece to be cut using the electrodeposited grindstones 1 and 5. For example, it can be used for cutting various materials such as semiconductor materials such as silicon and SiC, glass, ceramics, glass epoxy resins, and composite materials of resins and electrodes.

The work piece is cut by the abrasive grains exposed from the plating layers of the grindstone portions 3 and 9 coming into contact with the work piece. Then, when the cutting process is continued, the plating layer is worn and the exposed abrasive grains fall off, and new abrasive grains are exposed from the plating layer. This action is called a self-generated blade, and the self-generated blade maintains the cutting function of the grindstone.

However, in the grindstone portions 3 and 9 in which the abrasive grains are fixed by the plating layer containing nickel, the abrasive grains are relatively strongly fixed to the plating layer. Therefore, even if the workpiece is cut, the abrasive grains are less likely to fall off from the plating layer, and spontaneous blade formation is less likely to occur. In particular, when cutting a material (difficult-to-cut material) that is difficult to cut, such as glass, ceramics, glass epoxy resin, and a composite material of resin and electrode, spontaneous blade generation is less likely to occur. When cutting is performed on the grindstone portions 3 and 9 in such a state, processing defects such as chipping, which is called chipping, are formed on the workpiece.

Therefore, in the present embodiment, talc (hydrous magnesium silicate (Mg ₃ Si ₄ O ₁₀ (OH) ₂ )) is contained in the grindstone portion 3 of the electrodeposition grindstone 1 and the grindstone portion 9 of the electrodeposition grindstone 5. Talc has a lower hardness than nickel (Mohs hardness 1), and if talc is contained in the grindstone portions 3 and 9, the plating layer becomes weak and easily wears, and it can be expected that spontaneous blade generation is promoted. By appropriately generating spontaneous blades, the cutting functions of the electrodeposited grindstones 1 and 5 can be maintained, and the occurrence of machining defects during cutting can be suppressed.

Further, since talc is a material having lubricity, it can be expected that if talc is contained in the grindstone portions 3 and 9, the friction between the electrodeposited grindstones 1 and 5 and the workpiece during cutting is reduced. .. By reducing this friction, the occurrence of cutting defects such as chipping of the workpiece during cutting is suppressed.

The amount of talc contained in the grindstone portions 3 and 9 can be appropriately set according to the material of the plating layer, the material and particle size of the abrasive grains, the material of the workpiece, etc., but it reduces processing defects and reduces processing defects. Moreover, it is preferable to set the strength of the electrodeposition grindstones 1 and 5 within a range in which the strength is maintained above a certain level.

For example, the content of talc with respect to the grindstone portions 3 and 9 is 2.0% by volume or more and 15.0% by volume or less, preferably 2.2% by volume or more and 15.0% by volume or less, and more preferably 2.2% by volume or less. The talc can be contained in the grindstone portions 3 and 9 so as to be 6.2% by volume or less. The content of this talc can be measured, for example, by the Archimedes method.

Further, the particle size of talc can be appropriately set in the same manner as the content of talc. For example, talc having an average particle size of 0.6 μm or more and 10.0 μm or less as measured by a laser diffraction method can be used.

As described above, by containing talc in the grindstone portions 3 and 9 in which the abrasive grains are fixed by the plating layer containing nickel, it is possible to suppress processing defects during cutting.

Next, an example of a method for manufacturing an electrodeposited grindstone containing talc in the grindstone portion will be described. The electrodeposition grindstone 1 shown in FIG. 1A and the electrodeposition grindstone 5 shown in FIG. 1B can be manufactured by using electrolytic plating or the like, respectively.

FIG. 2 is a cross-sectional view schematically showing a configuration example of a manufacturing apparatus 2 used for manufacturing a washer-type electrodeposition grindstone 1. As shown in FIG. 2, when manufacturing the electrodeposited grindstone 1, first, a plating bath 4 containing a nickel plating solution 16 mixed with abrasive grains such as diamond is prepared. The material of the nickel plating solution 16 can be arbitrarily selected, and for example, an electrolytic solution containing nickel such as nickel sulfate or nickel nitrate can be used.

Further, talc contained in the grindstone portion 3 of the electrodeposition grindstone 1 is added to the nickel plating solution 16. Specifically, as shown in FIG. 2, a mixed liquid 18 produced by mixing talc and a surfactant is added to the nickel plating liquid 16. This surfactant has a function of dispersing talc in the nickel plating solution 16. The material of the surfactant can be arbitrarily selected. When the mixed solution 18 is added to the nickel plating solution 16, talc is substantially evenly dispersed in the nickel plating solution 16.

Next, the disk-shaped base 20 and the nickel electrode 6 made of a metal material such as stainless steel or aluminum are immersed in the nickel plating solution 16 in the plating bath 4. A mask 22 corresponding to the desired shape of the grindstone portion 3 is formed on the surface of the base 20. For example, when the annular grindstone portion 3 as shown in FIG. 1A is formed, the mask 22 having the annular opening is formed when viewed from above.

Further, the base 20 is connected to the negative terminal (negative electrode) of the DC power supply 10 via the switch 8, and the nickel electrode 6 is connected to the positive terminal (positive electrode) of the DC power supply 10. The switch 8 may be arranged between the nickel electrode 6 and the DC power supply 10.

Next, the fan 14 is rotated by a rotary drive source 12 such as a motor to stir the nickel plating solution 16, and the switch 8 arranged between the base 20 and the DC power supply 10 is short-circuited. As a result, a direct current flows through the nickel plating solution 16 with the base 20 as the cathode and the nickel electrode 6 as the anode, and the plating layer containing nickel is electrodeposited on the region of the surface of the base 20 that is not covered with the mask 22. A grindstone portion 3 containing talc and abrasive grains is formed.

FIG. 3A is a cross-sectional view showing a state in which the grindstone portion 3 is formed on the surface of the base 20. As shown in FIG. 3A, in the region of the surface of the base 20 not covered by the mask 22, the annular grindstone portion in which talc and abrasive grains are substantially evenly dispersed in the plating layer containing nickel. 3 is formed.

After that, the grindstone portion 3 formed on the surface of the base 20 is peeled off from the base 20. FIG. 3B is a cross-sectional view showing how the grindstone portion 3 is peeled off from the base 20. As a result, the grindstone portion 3 is separated from the base 20, and a washer-type electrodeposited grindstone 1 composed of the grindstone portion 3 is obtained.

The electrodeposition grindstone 5 shown in FIG. 1B can also be manufactured by the same method as the electrodeposition grindstone 1. FIG. 4 is a cross-sectional view schematically showing a configuration example of a manufacturing apparatus 24 used for manufacturing a hub type electrodeposition grindstone 5. The description of the manufacturing apparatus 2 (FIG. 2) can be referred to except for the configurations described below.

First, similarly to the method for manufacturing the electrodeposited grindstone 1, a plating bath 4 containing a nickel plating solution 16 mixed with abrasive grains such as diamond is prepared. Then, the mixed liquid 18 produced by mixing talc and the surfactant is added to the nickel plating liquid 16. Since the materials that can be used for the nickel plating solution 16 and the mixed solution 18 are the same as the manufacturing method of the electrodeposition grindstone 1, the description thereof will be omitted.

Next, the base 26 made of a metal material such as stainless steel or aluminum and the nickel electrode 6 are immersed in the nickel plating solution 16 in the plating bath 4. Since the base 26 becomes the base 7 (see FIG. 1 (B)) that supports the grindstone portion 9 of the electrodeposition grindstone 5 through a later process, the shape of the base 26 corresponds to the base 7. And.

Specifically, as shown in FIG. 5A, the base 26 is formed in an annular shape corresponding to the shape of the base 7 of the electrodeposition grindstone 5, and a through hole 26a is formed in the center thereof. It is provided. This through hole corresponds to the through hole 7a (see FIG. 1 (B)) provided in the central portion of the base 7.

A mask 28 corresponding to the desired shape of the grindstone portion 9 is formed on the surface of the base 26. For example, when the annular grindstone portion 9 is formed along the outer edge portion of the base 7 as shown in FIG. 1 (B), the annular grindstone portion 9 formed along the outer edge portion of the base 26 is viewed from above. A mask 28 with an opening is formed. Then, in the same manner as in the method for manufacturing the electrodeposited grindstone 1, a plating layer containing nickel is electrodeposited on a region of the surface of the base 26 that is not covered with the mask 28, and a grindstone portion 9 containing talc and abrasive grains is formed. Will be done.

After that, the mask 28 is removed from the base 26. As a result, the base 26 having the grindstone portion 9 formed on the surface is obtained. FIG. 5A is a cross-sectional view showing a state in which the grindstone portion 9 is formed on the surface of the base 26.

Then, by etching the outer edge portion of the base 26, a part of the grindstone portion 9 covered with the base 26 is exposed. As a result, as shown in FIG. 5B, a hub-type electrodeposited grindstone 5 in which the grindstone portion 9 is formed on the outer edge portion of the base 7 is obtained. Further, the shape of the grip portion 7b may be adjusted by the above etching.

By using the above manufacturing method, the electrodeposited grindstones 1 and 5 provided with the grindstone portions 3 and 9 containing talc can be manufactured.

Next, the evaluation result of the electrodeposition grindstone including the grindstone portion containing talc will be described. Here, the machining accuracy is measured by cutting the workpiece with multiple electrodeposited grindstones containing different amounts of talc in the grindstone and measuring the size of the chipping (chipping) generated in the workpiece by cutting. Was evaluated. In addition, the elastic moduli of a plurality of electrodeposited grindstones having different amounts of talc contained in the grindstone portion were measured, and the strength of the electrodeposited grindstone was evaluated from this elastic modulus.

For the evaluation, a washer-type (see FIG. 1 (A)) electrodeposited grindstone having talc contained in the grindstone portion manufactured according to the above-mentioned manufacturing method was used. The outer diameter of the electrodeposited grindstone was 53.4 mm, the inner diameter was 40 mm, the thickness was 0.10 mm, and diamond grains having an average particle size of 9 μm when classified by sieving were used as the abrasive grains. The concentration ratio of the abrasive grains was 50 (12.5% by volume).

Further, in order to evaluate the influence of the talc content, seven types of electrodeposited grindstones having different amounts of talc contained in the grindstone portion were prepared. To prepare the electrodeposited grindstone, talc having an average particle size of 0.8 μm as measured by a laser diffraction method was used. When the amount of talc contained in the grindstone portion of the seven types of electrodeposited grindstones produced was measured using the Archimedes method, each of the seven types of grindstone portions was 0.0% by volume (talc) with respect to the grindstone portion. , 1.0% by volume, 2.2% by volume, 6.2% by volume, 11.4% by volume, 15.0% by volume, 17.5% by volume of talc. Was there.

Next, each of the seven types of electrodeposited grindstones was shaped, and sharpened and rounded. After that, the workpiece is sucked and held by the chuck table of the cutting device, and the electrodeposited grindstone is cut into the workpiece while supplying cutting water (pure water at a water temperature of 20 ° C.) to the electrodeposited grindstone. Was cut for each of the seven types of electrodeposited grindstones.

As the work piece, borosilicate glass having a length of 100 mm, a width of 100 mm, and a thickness of 0.4 mm was used. Then, the electrodeposition grindstone is rotated at a speed of 30,000 rpm, and the electrodeposition grindstone is arranged so that the lower end thereof is located below the lower end of the workpiece, and is substantially parallel to the length direction of the workpiece. The workpiece was cut by relatively moving the workpiece and the electrodeposited grindstone at a speed of 5 mm / s along the same direction. By performing this cutting process 19 times at intervals of 5.0 mm in the width direction of the workpiece, the workpiece was divided into 20 small pieces.

Then, the chuck table was rotated by 90 ° in the horizontal direction, and the workpiece was cut along a direction substantially parallel to the width direction under the same conditions, so that each small piece was further divided into 20 pieces. In this way, the workpiece was divided into 400 chips.

After that, 5 chips were selected from the obtained 400 chips, and for each of the 5 chips, the length of the chipping generated on the cutting surface by the cutting in the direction perpendicular to the thickness direction of the workpiece. Was measured. Then, the maximum length of chipping was set as the chipping size, and the average value (average chipping size) of the chipping sizes of the five chips was calculated.

The above average chipping size was calculated for each of the chips obtained by using seven types of electrodeposited grindstones having different talc contents. FIG. 6 is a graph showing the relationship between the amount of talc contained in the grindstone portion of the electrodeposited grindstone and the average chipping size. In FIG. 6, the average chipping size of the tip obtained by using an electrodeposition grindstone containing no talc (an electrodeposition grindstone having a talc content of 0.0% by volume) is used as a reference (100%). The ratio of the average chipping size of the chips obtained by using the electrodeposition grindstone of No. 1 is shown.

As shown in FIG. 6, when the talc content is 2.2% by volume or more, the average chipping size is significantly reduced. This is because when the content of talc is 2.2% by volume or more, the plating layer contained in the grindstone is weakened by the talc and spontaneous blades are generated appropriately, and the lubricity of the talc causes the electrodeposited grindstone and the workpiece to be processed. It is presumed that the friction with the object was reduced and the processing accuracy was improved. Therefore, the amount of talc contained in the grindstone portion of the electrodeposition grindstone is particularly preferably 2.2% by volume or more.

Further, in order to evaluate the strength of seven types of electrodeposited grindstones having different talc contents, the elastic modulus of each electrodeposited grindstone was measured. The elastic modulus was calculated from the stress-strain curve obtained by applying a predetermined load to the tip of the electrodeposited grindstone after cutting. Then, the strength of the electrodeposited grindstone was evaluated, assuming that the electrodeposited grindstone having a higher elastic modulus is less likely to be deformed and has higher strength.

FIG. 7 is a graph showing the relationship between the amount of talc contained in the grindstone portion of the electrodeposited grindstone and the elastic modulus of the electrodeposited grindstone. In FIG. 7, the elastic modulus of the other electrodeposited grindstone is based on the elastic modulus (100%) of the electrodeposited grindstone containing no talc (electroplated grindstone having a talc content of 0.0% by volume). Shows the ratio of.

From FIG. 7, the elastic modulus of the electrodeposited grindstone having a talc content of 1.0% by volume or more and 6.2% by volume or less is higher than the elastic modulus of the electrodeposited grindstone containing no talc, and the strength is improved. ing. The reason why the elastic modulus of the electrodeposited grindstone increases when a small amount of talc is added in this way is not always clear, but when the amount of talc added is small, the talc particles are evenly dispersed inside the plating layer. It is presumed that this is to suppress the transition of the plating layer.

As the talc content increases from 1.0% by volume, the modulus of elasticity gradually decreases. It is presumed that this is because the plating layer contained in the grindstone portion became weak due to the increase in the talc content. However, it was not observed that the electrodeposited grindstone deformed and meandered during cutting with any of the electrodeposited grindstones, and it was confirmed that each electrodeposited grindstone had the strength required for cutting the workpiece.

However, when the talc content reaches 17.5% by volume, the elastic modulus ratio becomes about 30%, and it can be seen that the elastic modulus sharply decreases. With this electrodeposition grindstone, it may be particularly difficult to process difficult-to-cut materials. Therefore, in order to reduce the average chipping size without significantly reducing the strength of the electrodeposited grindstone, it is particularly preferable that the talc content is 2.2% by volume or more and 15.0% by volume or less.

Further, in particular, the electrodeposited grindstone having a talc content of 6.2% by volume or less has a high elastic modulus as compared with the electrodeposited grindstone containing no talc, and the strength of the electrodeposited grindstone is improved. Therefore, when the content of talc is 2.2% by volume or more and 6.2% by volume or less, the occurrence of chipping can be suppressed while improving the strength of the electrodeposited grindstone.

From the above evaluation results, by using an electrodeposited grindstone containing talc in the grindstone portion, it is possible to reduce chipping during cutting and perform highly accurate cutting.

In addition, the structure, method, and the like according to the above-described embodiment can be appropriately modified and implemented as long as they do not deviate from the scope of the object of the present invention.

1 Electroplated whetstone 3 Whetstone part 3a Through hole 5 Electroplated whetstone 7 Base 7a Through hole 7b Grip part 9 Whetstone part 2 Manufacturing equipment 4 Plating bath 6 Nickel electrode 8 Switch 10 DC power supply 12 Rotating drive source 14 Fan 16 Nickel plating solution 18 Additives 20 Bases 22 Masks 24 Manufacturing equipment 26 Bases 28 Masks

Claims (5)

Equipped with a grindstone part where the abrasive grains are fixed with a plating layer containing nickel,
The electrodeposition grindstone is characterized in that the grindstone portion contains talc of 2.2% by volume or more and 15.0% by volume or less of the grindstone portion. The electrodeposition grindstone according to claim 1, wherein the grindstone portion contains talc of 2.2% by volume or more and 6.2% by volume or less of the grindstone portion. The electrodeposition grindstone according to claim 1 or 2, wherein the average particle size of talc contained in the grindstone portion is 0.6 μm or more and 10.0 μm or less. The electrodeposition grindstone according to any one of claims 1 to 3, wherein the electrodeposition grindstone is composed of only the annular grindstone portion. One of claims 1 to 3, wherein the electrodeposited grindstone is composed of an annular base having a grip portion and the grindstone portion formed on the outer edge portion of the base. The electrodeposition grindstone described in item 1.

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