JP2004291129A - Soft material machining tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low-cost machining and adjusting tool for a pad surface having superior adjusting action of the surface of the pad and being stable for a long period of time. <P>SOLUTION: A plurality of projection parts 12 with flat upper surfaces 13 are provided on the surface 11 of a base 10. An area s1 of the upper surface 13 per projection is set to a range of 0.01-1 mm<SP>2</SP>. A ratio S1/S2 of the total area S1 of the upper surfaces 13 of the plurality of projection parts 12 to the area S2 of the surface 11 of the base 10 is set to a range of 0.0001-0.01. The whole body of the base 10 including a cutting blade 14 in the projection part 12 is constituted of ceramic. The minimum distance (d) between a plurality of projection parts 12 is set to 1 mm or more. The height h(mm) per projection in relation to the area s1 (mm<SP>2</SP>) of the upper surface per projection is set to the range of (0.091xs1+0.009)-(0.81xs1+0.19). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a tool for processing and adjusting the surface of a pad made of porous resin, rubber, polyurethane rubber, or the like, for example, a polishing pad such as a semiconductor wafer.
[0002]
[Prior art]
In recent years, with the progress of the semiconductor industry, the necessity of a processing method for finishing a surface of metal, semiconductor, ceramic, or the like with high precision has increased. In particular, semiconductor wafers are required to have a surface finish on the order of nanometers (1/1000 micron) together with an improvement in the degree of integration. For this reason, CMP polishing (mechanochemical) using a porous pad (polishing cloth) has been required. Polishing) is common.
[0003]
Pads used for polishing such semiconductor wafers and the like are subject to clogging and compression deformation as the polishing time elapses, and the surface state gradually changes. Then, undesired phenomena such as a decrease in the polishing rate occur, so the surface of the pad is periodically processed, adjusted, and roughened, so that the surface state of the pad is kept constant and a good polishing state is maintained. Is being done. Recently, polishing has been used to flatten the irregularities even during the semiconductor device manufacturing process. In such a case, the polishing rate ratio between the concave portion and the convex portion is increased. For this reason, the use of pads requiring stronger surface conditioning, such as pads made of polyurethane rubber having closed cells, is increasing.
[0004]
By the way, conventionally, in order to process and adjust these pads, a grindstone called a pad conditioner has been generally used. The following pad conditioners are known.
First, there is a pad conditioner using a sintered jig such as magnesia or silica having a plurality of grooves or holes formed on the surface. These pad conditioners are, for example, as shown in FIGS. A plurality of holes 3 or grooves 4 are formed on a surface 2 of a pad conditioner 1 having a substantially disk shape (FIGS. 5 and 6) or a substantially rectangular parallelepiped shape (FIG. 7). The surface of the pad is processed and adjusted by performing a rotary motion and, in some cases, a translational motion in a substantially disk-shaped pad conditioner, and a translational motion in a substantially rectangular parallelepiped pad conditioner. Things.
[0005]
Secondly, there is a pad conditioner using an electrodeposited diamond plate. As shown in FIGS. 8 and 9, the pad conditioner is provided on the surface 6 of a substantially disk-shaped base material 5 made of, for example, stainless steel. And an abrasive layer 7 in which diamond abrasive grains 8 are fixed with a metal binding phase 9 such as nickel. The surface 6 is pressed against the surface of the pad, and a rotational movement, and in some cases, a translational movement is performed. By doing, the surface of the pad is processed and adjusted.
[0006]
However, in the above-described first pad conditioner, the sintered body of magnesia, silica, or the like has insufficient mechanical strength and toughness, and stably maintains the pad surface adjusting action for a long period of time. I couldn't do that.
[0007]
Further, in the above-mentioned second pad conditioner, since the diamond abrasive grains 8 having a high hardness are used, the adjusting effect of the pad surface is maintained for a certain period as compared with the first pad conditioner. However, since the diamond abrasive grains 8 are expensive, the price of the pad conditioner itself increases.
In addition, the diamond abrasive grains 8 fixed to the metal bonding phase 9 and exposed on the surface have a microscopic variation in height, and the corners of the diamond abrasive grains 8 used for polishing the pad. However, in many cases, the surface of the pad is ground at the corners of the diamond abrasive grains 8 at a very obtuse angle, as shown in FIG. Can not be ground.
[0008]
In fact, in the case of a pad conditioner using an electrodeposited diamond plate, even if the diamond abrasive grains 8 are incorporated in the metal bonding phase 9 by 50 vol%, the diamond abrasive grains 8 acting on the grinding are 5 to 10 vol. %, And it was a reality that efficient grinding was not performed instead of using expensive diamond abrasive grains 8.
Also, since the angle of the corner of the diamond abrasive grains 8 to be ground is dull, even when a large number of holes are to be exposed on the surface to increase the effectiveness in the CMP polishing, such as in the case of polishing a pad made of polyurethane rubber, it is difficult to use the hole. As a result, the grinding efficiency was poor and the surface finish of the pad was not satisfactory.
[0009]
Here, as another conventional technique, for example, there is a pad conditioner to which a technique of a vapor-phase synthetic diamond is applied as disclosed in Patent Literature 1 and Patent Literature 2.
In these, a plurality of grooves, holes or projections are formed on the surface of the base material, and the entire surface is coated with vapor-phase synthetic diamond.In such a pad conditioner, This is effective in preventing contamination from the material constituting the base material and the metal binding phase to which the diamond abrasive grains adhere.
[0010]
[Patent Document 1]
JP-A-7-328937
[Patent Document 2]
JP-A-10-44023
[0011]
[Problems to be solved by the invention]
Each of the pad conditioners disclosed in Patent Document 1 and Patent Document 2 described above uses gas-phase synthetic diamond instead of electrodeposited diamond abrasive grains, and can provide sufficient wear resistance. Unlike diamond abrasive grains, they do not fall off from the substrate, but are easily clogged between grooves, holes, or convex portions that do not have a sufficient space formed on the surface of the substrate, and therefore, processing efficiency and padding Considering the surface finish, it could not be said that a sufficient effect could be obtained.
[0012]
The present invention has been made in view of the above problems, and provides a tool for processing and adjusting a pad surface that is excellent in adjusting the surface of a pad, is stable over a long period of time, and is inexpensive. The purpose is to:
[0013]
[Means for Solving the Problems]
In order to solve the above-mentioned problems and achieve such an object, the present inventors have made intensive developments, and as a result, are not bound by the concept of a grinding tool such as a conventional pad conditioner, and how sharp and efficient the tool is. By incorporating the concept of cutting, especially face milling, into the polishing of the pad, taking into account the possibility of machining, a tool having a number of independent cutting edges on the surface of the substrate has been invented.
[0014]
In face milling, a milling tool in which a plurality of cutting blades are implanted on the outer periphery of the tip of a substantially disk-shaped tool body is rotated around the axis of the milling tool, and the surface of the workpiece is moved laterally. Then, the surface of the work material is cut by giving a cutting depth of a predetermined depth. In order to perform this process well, it is important to have a sharp cutting edge and to smoothly discharge chips generated during the cutting process. The material, shape, angle, and the like of the blade are variously devised, and a tip pocket is provided for each cutting blade so that chips are smoothly discharged, and the depth, shape, and the like are devised.
[0015]
The same concept was applied to the tool for processing and adjusting the pad surface of the present invention, that is, a cutting edge showing excellent sharpness for a pad (work material) made of resin, rubber, polyurethane rubber, or the like. The object of the present invention is to provide a tool that enables highly efficient machining by providing an appropriate space for smoothly discharging chips generated by the cutting blade on the surface of the base material.
In this case, the major difference from normal face milling is that the work material is a material that elastically deforms. For this reason, if the cutting resistance is high, the cutting edge may cut into the work material. And the pad surface cannot be processed at all.
Therefore, it is necessary to reduce the cutting resistance per cutting edge as much as possible, and it is necessary to reduce the cutting edge as much as possible, and to reduce the cutting depth. Therefore, it is necessary to provide many such small cutting blades on the surface of the base material.
[0016]
On the other hand, these chips of the work material that undergo elastic deformation cannot be expected to break due to work hardening (so-called breaking), unlike chips of a work material made of ordinary metal, and are generated continuously. For this reason, if there is not enough space for chip discharge, clogging is easily performed and machining cannot be performed.Therefore, it is necessary to appropriately set the size of the cutting blade and to determine the size of the cutting blade. How to secure the space for discharging the chips by providing them at intervals is a major problem in performing efficient machining.
[0017]
On the other hand, these cutting blades need to be kept small and sharp, but if there is not enough abrasion resistance, no matter how much the work material is soft such as resin, rubber, polyurethane rubber, Immediately the cutting blade is worn and the sharpness is reduced. In addition, as the cutting edge becomes smaller, the strength becomes weaker. Therefore, it is also a big problem how to give the cutting blade strength.
[0018]
The present invention has been made as a result of intensive studies based on these findings, and a plurality of convex portions are provided on the surface of the base material, and a flat surface exists on the upper surface of the convex portion, and the flat surface exists. Is a cutting edge, and the area s1 of the flat surface on the upper surface per one protrusion is 0.01 to 1 mm. ² The ratio S1 / S2 of the total area S1 of the flat surfaces on the upper surfaces of the plurality of projections and the area S2 of the surface of the base material is set in the range of 0.0001 to 0.01. Still further, at least a cutting blade portion in the convex portion is made of ceramics.
[0019]
In the soft material processing tool having such a configuration, the area s1 of the flat surface on the upper surface per one convex portion formed on the surface of the base material is 0.01 to 1 mm. ² Is set to a small value, the cutting edge formed on the ridge of this flat surface can be kept small and sharp, cutting resistance can be reduced, and a pad made of a material that elastically deforms In addition to this, excellent sharpness can be obtained, the cutting edge does not become too small, and the cutting efficiency does not decrease and the strength of the projections does not decrease.
In addition, since the ratio S1 / S2 of the total area S1 of the flat surfaces on the upper surfaces of the plurality of projections to the area S2 of the surface of the base material is set to a small value of 0.0001 to 0.01, In other words, it is possible to secure a sufficient space for discharging chips generated by the cutting blade, without causing clogging and reducing the number of convex portions. Is not extremely reduced, and the cutting efficiency is not reduced.
Furthermore, since at least the cutting edge portion in the convex portion is made of ceramics, it is possible to impart abrasion resistance to this small cutting edge, so that it is not necessary to use expensive diamond abrasive grains as in the past. In addition, it is possible to exhibit a stable pad adjusting operation without deteriorating the sharpness over a long period of time.
Here, the area s1 of the flat surface on the upper surface per projection is 0.01 mm. ² If the diameter is smaller, the cutting edge to be used for cutting becomes too small, which may cause a decrease in cutting efficiency or a decrease in the strength of the convex portion, while the area s1 is 1 mm. ² If the size is larger, the cutting edge used for cutting becomes too large, and the cutting resistance becomes too high, so that the pad surface may not be machined.
Further, when the ratio S1 / S2 of the total area S1 of the flat surfaces on the upper surfaces of the plurality of projections to the area S2 of the surface of the base material is smaller than 0.0001, the number of projections becomes too small, and cutting is performed. On the other hand, if the area ratio S1 / S2 is larger than 0.01, the total area of the flat surface on the upper surface of the convex portion becomes large, and the cutting resistance becomes too high, so that the pad surface is reduced. Processing may not be possible.
[0020]
In addition, the plurality of protrusions formed on the surface of the base material do not all need to be arranged at substantially equal intervals, but the shortest distance between the plurality of protrusions is set to 1 mm or more. When the shortest distance is smaller than 1 mm, a space formed between the convex portions for discharging chips cannot be sufficiently secured, and clogging may easily occur. is there.
[0021]
Further, the height h [mm] per one convex portion is equal to the area s1 [mm of the flat surface on the upper surface per one convex portion. ² Is preferably set in the range of (0.091 · s1 + 0.009) to (0.81 · s1 + 0.19), and the height h is (0.091 · s1 + 0.009). If the height h is smaller than the above, the cutting amount given to the cutting edge of the convex portion may not be large, and the cutting efficiency may be reduced. On the other hand, if the height h is larger than (0.81 · s1 + 0.19). In addition, the projections may be too elongated, and the strength may be reduced.
[0022]
Further, the above ceramics may constitute only the cutting edge portion in the convex portion, but it is preferable to constitute at least the entire surface of the substrate so as to include the convex portion. Thus, contamination due to elution of the base material can be prevented, and the strength of the projections can be further improved.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a plan view of a soft material processing tool according to the present embodiment, FIG. 2 is an enlarged plan view of a main part of the soft material processing tool, and FIG. 3 is an enlarged cross-sectional view of a main part of the soft material processing tool.
In these drawings, the description is exaggerated for the sake of simplicity, and the definition of detailed numerical values and the like is as described later.
[0024]
The base material 10 of the soft material processing tool according to the present embodiment has a substantially disk shape, and a plurality of upwardly protruding protrusions 12 are formed in a peripheral region of the surface 11 excluding a central region. ing.
Each of the plurality of projections 12 has a substantially square pillar shape of the same shape, and the entire upper surface 13 is a flat surface substantially parallel to the surface 11 of the base material 10 and the upper surface 13 (flat surface). Surface), that is, four cutting edges 14 are formed at the intersection ridge line between the upper surface 13 and the four side surfaces.
[0025]
The area s1 of the upper surface 13 (flat surface) per one protrusion is 0.01 to 1 mm. ² In this embodiment, the area s1 of the upper surface 13 is, for example, 0.04 mm. ² (The upper surface 13 forms a square having a side a of 0.2 mm).
Furthermore, the total area S1 of the upper surface 13 (flat surface) of all the protrusions 12 formed on the surface of the substrate 10 and the area S2 of the surface 11 of the substrate 10 (the planar The ratio S1 / S2 with respect to the area of the surface 11 is set in the range of 0.0001 to 0.01, and in the present embodiment, the area ratio S1 / S2 is set to, for example, 0.00245.
[0026]
In addition, these convex parts 12 are arrange | positioned at substantially equal intervals via the space | interval of the same distance mutually, The shortest distance d between the convex parts 12 is set to 1 mm or more, In this embodiment, , The shortest distance d (the distance between adjacent convex portions 12) is set to, for example, 3 mm.
[0027]
Regarding the shape of the projection 12, the height h [mm] per projection is equal to the area s1 [mm] of the upper surface 13 (flat surface) per projection. ² In the relationship with (0.01 ≦ s1 ≦ 1), the distance is set in the range of (0.091 · s1 + 0.009) to (0.81 · s1 + 0.19). Has a height h of, for example, 0.04 mm.
[0028]
More specifically, as shown in FIG. 4, the X-axis is defined as the area s1 [mm] of the upper surface 13 (flat surface) per projection. ² And the height h [mm] of the convex portion 12 is defined as four straight lines L1 (h = 0.81 · s1 + 0.19), where Y is the height h [mm] per convex portion. ), L2 (h = 0.091 · s1 + 0.009), L3 (s1 = 1), and L4 (s1 = 0.01). In addition, the height h [mm] of the convex portion 12 is set in the range of 0.00991 (about 0.01) to 1 mm in consideration of the above-described hatched area.
[0029]
The base material 10 in which the plurality of protrusions 12 are arranged at substantially equal intervals is formed by, for example, cutting a flat surface of a substantially disk-shaped base material into a plurality of predetermined widths (adjacent to a predetermined width). It is manufactured by forming the vertical groove and the horizontal groove (the distance between the convex portions 12) at substantially regular intervals so as to be orthogonal to each other.
[0030]
In the base material 10 as described above, at least the cutting edge 14 of the projection 12 formed integrally with the surface 11 is made of ceramics (a wear-resistant material having a hardness of 13 GPa or more Vickers hardness). In the present embodiment, the entire substrate 10 including the entire surface 11 of the substrate 10 on which the plurality of protrusions 12 are formed is made of ceramics.
Here, with respect to ceramics as a material constituting the base material 10, for example, SiC, SiC, and the like are used from the viewpoints of the ease of forming the projections 12 and the mechanical properties for practical use. ₃ N ₄ And alumina.
[0031]
In the soft material processing tool configured as described above, a plate material made of SUS, resin, or the like is attached to the back surface of the base material 10, or the base material 10 is shrink-fitted into a dent formed in the plate material such as SUS. After being assembled, it will be used for actual processing.
Then, the soft material processing tool in the assembled state presses the surface 11 of the base material 10 against the surface of a pad made of, for example, a porous resin, rubber, polyurethane rubber, and rotates and, in some cases, By performing the translational motion, the surface of the pad is cut with the cutting edge 14 formed on the ridge of the upper surface 13 of the plurality of projections 12 as if it were a cutting tool such as a face mill. The chips generated in this way are discharged through gaps formed between the convex portions 12.
[0032]
In such a soft material processing tool, the area s1 of the flat upper surface 13 (flat surface) per one protrusion formed on the surface 11 of the base material 10 is 0.01 to 1 mm. ² Since the cutting edge 14 formed on the ridge of the flat upper surface 13 (flat surface) is kept small and sharp, the cutting resistance can be reduced. Even with a pad made of an elastically deformable material such as porous resin, rubber, polyurethane rubber, etc., the small cutting blade 14 is stably cut into the surface of the pad with excellent sharpness. And the cutting edge 14 does not become extremely small, so that the strength of the projection 12 and the cutting efficiency are not reduced.
[0033]
Here, the area s1 of the upper surface 13 (flat surface) per projection is 0.01 mm. ² If the diameter is smaller, the cutting edge 14 provided for cutting becomes too small, which causes a decrease in cutting efficiency and strength of the convex portion 12, while the area s1 is 1 mm. ² If the size becomes larger, the cutting edge 14 provided for the cutting becomes too large, and the cutting resistance increases, and there is a possibility that the surface of the pad cannot be machined.
In order to secure the above-described effects more reliably, the area s1 of the upper surface 13 (flat surface) of the projection 12 should be 0.02 to 0.5 mm. ² Is preferably set in the range.
[0034]
Further, the ratio S1 / S2 of the total area S1 of the upper surfaces 13 (flat surfaces) of the plurality of protrusions 12 to the area S2 of the surface 11 of the base material 10 is set to a small value of 0.0001 to 0.01. Therefore, it is possible to secure a necessary and sufficient space between the plurality of convex portions 12, that is, a space for discharging the chips generated by the cutting blade 14, thereby causing clogging. In addition, the number of the protrusions 12 does not extremely decrease, and the cutting efficiency does not decrease.
[0035]
Here, when the ratio S1 / S2 of the total area S1 of the upper surfaces 13 (flat surfaces) of the plurality of protrusions 12 to the area S2 of the surface 11 of the base material 10 is smaller than 0.0001, the number of protrusions 12 Is too small to reduce the cutting efficiency. On the other hand, when the area ratio S1 / S2 is larger than 0.01, the total area S1 of the upper surfaces 13 (flat surfaces) of the plurality of convex portions 12 is increased. Accordingly, the cutting resistance becomes too high, and there is even a possibility that the pad surface cannot be machined.
In order to ensure the above-described effects, the area ratio S1 / S2 is preferably set in the range of 0.0005 to 0.005.
[0036]
Furthermore, since the entire substrate 10 is formed of ceramics, including the cutting edge 14 portion of the projection 12, sufficient wear resistance can be given to this small cutting edge 14, Even if expensive diamond abrasive grains are not used, it is possible to maintain a stable pad adjusting action without deteriorating sharpness over a long period of time, and further improve the strength of the convex portion 12. be able to.
[0037]
Further, since the plurality of protrusions 12 formed on the surface 11 of the base material 10 are arranged such that the shortest distance d between the protrusions 12 is 1 mm or more, the cutting edge 14 A sufficient space for discharging generated chips can be secured.
Here, if the shortest distance d is smaller than 1 mm, it is not possible to secure a sufficient space for discharging chips, which is formed between the protruding portions 12, so that clogging may occur. It is easy to occur.
In order to ensure the above-described effects, the shortest distance d is preferably set to 1.5 mm or more.
[0038]
In addition, the height h per one protrusion is the area s1 [mm] of the upper surface 13 (flat surface) per one protrusion. ² [0.091 · s1 + 0.009] to (0.81 · s1 + 0.19), it is possible to form the convex portion 12 having an appropriate shape. In addition, the strength of the pad can be kept high, and the amount of cut into the surface of the pad can be sufficiently ensured.
Here, if the height h is smaller than (0.091 · s1 + 0.009), the cutting amount given to the cutting edge 14 of the convex portion 12 cannot be made large, and the cutting efficiency is reduced. If the height h is larger than (0.81 · s1 + 0.19), the convex portion 12 becomes too elongated, and its strength is reduced.
In order to ensure the above-described effects, the height h is preferably set in the range of 0.02 mm to 0.5 mm.
[0039]
In the present embodiment, on the front surface 11 of the base material 10, each of the plurality of protrusions 12 is located immediately in front of the rotation direction (workpiece cutting direction) due to the rotation of the base material 10. A through hole for discharging the chips generated by the cutting blade 14 may be provided. With such a configuration, the effect of discharging the chips can be further improved, and the occurrence of clogging and the like can be reliably prevented. Become. At this time, if these through holes extend from the surface 11 of the base material 10 to the outer peripheral side of the base material 10 and the rear side in the rotation direction, and are opened on the side surfaces of the base material 10, It is also possible to automatically discharge the chips entering the through holes to the outer peripheral side of the base material 10 by centrifugal force due to the movement.
[0040]
Further, in the present embodiment, the substantially disc-shaped base material 10 is used, but the present invention is not limited to this, and the base material may have another shape, for example, a substantially rectangular parallelepiped base having a flat surface. It is assumed that the pad surface has been processed and adjusted using a material or a substrate having a convexly curved surface (substantially columnar substrate having an outer peripheral surface (surface) having an arc-shaped cross section). However, the above-described effect can be obtained without any inferiority.
[0041]
In the present embodiment, the entire upper surface 13 of the convex portion 12 is a flat surface. However, the present invention is not limited to this, as long as the upper surface 13 of the convex portion 12 has a flat surface. Good. For example, the upper surface 13 of the convex portion 12 may have a flat surface with a concave portion which is concave toward the surface 11 side of the base material 10, or the ridge portion thereof may be chamfered. It may have a flat surface (in this case, not only the ridge portion of the flat surface existing on the upper surface 13 of the convex portion 12 acts as a cutting edge, but also the intersection of surfaces formed by chamfering). Ridges may also act as cutting edges.)
Furthermore, in the present embodiment, the flat surface existing on the upper surface 13 of the convex portion 12 is substantially parallel to the surface 11 of the base material 10, but is not limited thereto. The flat surface existing on the upper surface 13 may have a slight inclination with respect to the surface 11 of the substrate 10.
[0042]
【The invention's effect】
As described above, the soft material processing tool according to the present invention is not restricted by the concept of a grinding tool such as a conventional pad conditioner, but incorporates the concept of cutting into the polishing of a pad. A large number of small, sharp, independent cutting blades are used to reduce cutting resistance, exhibit excellent sharpness even for pads made of porous resin, rubber, polyurethane rubber, etc. It is possible to secure a sufficient space for discharging chips. In addition, since the cutting edge portion is made of ceramic, the small cutting edge is provided with abrasion resistance, and the sharpness can be maintained over a long period of time without using expensive diamond abrasive grains as in the past. And excellent pad adjusting action can be stably exhibited without deteriorating the performance.
[Brief description of the drawings]
FIG. 1 is a plan view of a soft material processing tool according to an embodiment.
FIG. 2 is an enlarged plan view of a main part of the soft material processing tool according to the embodiment.
FIG. 3 is an enlarged sectional view of a main part of the soft material processing tool according to the embodiment.
FIG. 4 is an explanatory graph used to define the shape of a convex portion of the soft material processing tool according to the embodiment.
FIG. 5A is a plan view showing an example of a conventional pad conditioner, and FIG. 5B is a cross-sectional view of FIG.
6A is a plan view showing an example of a conventional pad conditioner, and FIG. 6B is a cross-sectional view of FIG.
7A is a plan view showing an example of a conventional pad conditioner, and FIG. 7B is a cross-sectional view of FIG.
FIG. 8A is a plan view showing an example of a conventional pad conditioner, and FIG. 8B is a side view of FIG.
9 is an enlarged cross-sectional view showing a state of processing the surface of the pad using the pad conditioner shown in FIG.
[Explanation of symbols]
10 Substrate
11 Surface
12 convex part
13 Top surface (flat surface)
14 Cutting blade
s1 Area of upper surface per one convex part
S1 Total area of the upper surface of the plurality of projections
S2 Area of substrate surface
d Shortest distance between convex parts

Claims (4)

A plurality of protrusions are provided on the surface of the base material, and a flat surface exists on the upper surface of the protrusions, and a ridge portion of the flat surface is a cutting edge,
The flat surface area s1 on the upper surface per one convex portion is set in a range of 0.01 to ¹ mm ² ,
The ratio S1 / S2 of the total area S1 of the flat surfaces on the upper surfaces of the plurality of protrusions and the area S2 of the surface of the base material is set in a range of 0.0001 to 0.01,
Furthermore, a soft material processing tool characterized in that at least a cutting edge portion of the convex portion is made of ceramics. The tool for processing a soft material according to claim 1,
A tool for processing a soft material, wherein a shortest distance between the plurality of protrusions is set to 1 mm or more. The soft material processing tool according to claim 1 or 2,
Height h (mm) per one said protrusion is in relation to the area of the flat surfaces s1 [mm ^2] on the upper surface of one per the convex portion, (0.091 · s1 + 0.009) ~ (0 .81 · s1 + 0.19). The soft material processing tool according to any one of claims 1 to 3,
A tool for processing a soft material, wherein at least the entire surface of the substrate is made of the ceramic.

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