JP2003175461A - Cutting tool with diamond coating - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To regulate a cutting speed and a cut depth individually. <P>SOLUTION: A relation between an angle θ<SB>a</SB>(>0°) formed by a direction N orthogonal to a surface 11 of a substrate 10 and a wall face 12A adjacent to a front side in a rotational direction T of a cutting blade edge line 13, and an angle θ<SB>b</SB>(>0°) formed by the direction N orthogonal to the surface 11 of the substrate 10 and a wall face 12B adjacent to a rear side in the rotational direction T of the cutting blade edge line 13 is brought into θ<SB>a</SB>≠θ<SB>b</SB>, θ<SB>a</SB><θ<SB>b</SB>, 10°≤θ<SB>a</SB><45°, and 45°≤(θ<SB>a</SB>+θ<SB>b</SB>)≤90°, in view of a cross section along the rotational direction T of a cutting blade edge line 13 of each protrusion 12. A layer thickness (t) of a coating layer of a diamond 15 synthesized by a vapor-phase process is set within a range of 0.5-20 μm. The whole face of the surface 11 in the substrate 10 is coated by the diamond 15 synthesized by the vapor-phase process. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a pad made of porous resin, rubber, polyurethane rubber, etc., for example,
The present invention relates to a tool for processing and adjusting the surface of a polishing pad such as a semiconductor wafer.

[0002]

2. Description of the Related Art In recent years, with the progress of the semiconductor industry, the need for a processing method for finishing surfaces of metals, semiconductors, ceramics, etc. with high precision has increased. In particular, semiconductor wafers have nano-micron (1/100
A surface finish on the order of 0 micron has been required, and for this reason, using a porous pad (polishing cloth), C
MP polishing (mechanochemical polishing) is commonly used.

Pads used for polishing such semiconductor wafers are clogged and compressively deformed as the polishing time elapses, and their surface condition gradually changes. Then, unfavorable phenomena such as a decrease in polishing rate will occur.Therefore, it is necessary to keep the surface condition of the pad constant and maintain a good polishing condition by regularly processing, adjusting and roughening the surface of the pad. Has been done.

By the way, as an example of a pad conditioner used for processing and adjusting this pad,
As disclosed in International Publication No. WO 01/26862 A1, there is one in which a plurality of symmetrical convex portions such as substantially square prisms protruding upward are formed by machining the surface of a substrate. . Such a pad conditioner presses the surface of the substrate against the surface of the pad that is being rotated about the axis with a constant load, so that the substrate performs a rotational movement along with the rotational movement of the pad. The surface of the pad is cut and processed and adjusted by the convex portion that cuts into the surface of the pad.

[0005]

However, in such a pad conditioner, since the convex portion forming the cutting edge is symmetrical, the inclination angle of the wall surface of the convex portion which faces the front side in the rotation direction and the convex portion. The angle of inclination of the wall surface facing the rear side in the rotation direction cannot be set independently. Then, the inclination angle of the wall surface that adjusts the processing speed by affecting the biting state of the convex portion on the pad surface, that is, the inclination angle of the wall surface of the convex portion that faces the front side in the rotation direction and the convex portion is the pad surface. The inclination angle of the wall surface that adjusts the depth of cut, that is, the inclination angle of the wall surface facing the front side and the rear side in the rotation direction of the convex portion is individually set by influencing the state of the cutting depth when it is pressed against Therefore, it is difficult to individually adjust the processing speed and the cutting depth.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a tool for machining and adjusting a pad surface, which is capable of individually adjusting a machining speed and a cutting depth.

[0007]

[Means for Solving the Problems] By solving the above problems,
In order to achieve such an object, the present invention provides a plurality of convex portions having cutting edge ridges on the surface of a substantially disk-shaped substrate rotated around an axis, and rotating the cutting edge ridges. When viewed in a cross section along the direction, an angle θa (> 0 °) formed by a direction orthogonal to the surface of the substrate and a wall surface continuous to the front side in the rotation direction of the cutting edge ridge in the convex portion, and the substrate Angle θb (> 0) formed by a wall surface that is continuous to the rear surface of the cutting edge ridge line in the direction of rotation of the convex portion.
The relationship with θ) is θa + θb ≦ 90 °, and θa ≠ θ
b, and at least the cutting edge ridge line portion of the convex portion is coated with vapor phase synthetic diamond. With such a configuration, by appropriately setting θa, the goodness of the cutting edge ridge to the pad surface, that is, the amount of cutting the surface of the pad is determined, and the processing speed is set to a desired value. However, by appropriately setting θa + θb in consideration of the previously set θa, the biting amount of the cutting edge ridgeline into the pad surface, that is, the cutting depth of the pad surface by the cutting edge ridgeline can be set to a desired value. Can be set. Further, since θa + θb which determines the cutting depth is 90 ° or less, it is possible to sufficiently secure the cutting depth on the pad surface by the cutting edge ridge line without increasing the cutting resistance.
Furthermore, at least the cutting edge ridge portion in the convex portion is coated with vapor phase synthetic diamond,
Since wear resistance can be imparted to the ridgeline of the cutting edge, it is possible to exhibit a stable pad adjusting action for a long period of time without deteriorating sharpness.

Further, it is preferable that θa <θb, and if θa> θb, when θa is set to a certain value and the processing speed is adjusted to a desired value,
In many cases, θa + θb cannot be secured sufficiently large, and there is a risk that the cutting depth will be set unnecessarily.

Further, it is preferable that 10 ° ≦ θa <45 °. If θa is smaller than 10 °, the processing speed can be increased, but it becomes difficult to secure a sufficient size of θa + θb, which is necessary. There is a possibility that the above cutting depth has to be set, and on the other hand, if θa is 45 ° or more, there is a possibility that the processing speed is reduced.

Further, it is preferable that 45 ° ≦ (θa + θb), and if (θa + θb) is smaller than 45 °, the depth of the cutting edge ridgeline into the pad surface becomes too large and the pad surface with respect to the pad surface. There is a possibility that an excessive cutting depth may be given to the ridgeline of the cutting edge.

Further, the layer thickness of the vapor phase synthetic diamond coating layer is preferably set in the range of 0.5 to 20 μm. When the layer thickness is smaller than 0.5 μm, it is given to the cutting edge ridge. The abrasion resistance is not sufficient and the life may be shortened. On the other hand, even when the coating layer thickness is larger than 20 μm, the coating layer may become brittle and crack easily. There is.

The vapor-phase synthetic diamond coating layer may be formed only on the cutting edge ridge portion of the convex portion, but is formed over the entire surface of the substrate so as to include the convex portion. With such a configuration, even if the substrate is made of a material that may cause contamination due to elution, the entire surface of the substrate is coated to prevent contamination due to elution. This can be prevented, and the strength of the convex portion can be further improved.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. First, a first embodiment of the present invention will be described. 1A is a plan view of the diamond-coated cutting tool according to the first embodiment, FIG. 1B is an enlarged perspective view of an essential part of FIG. 1A, and FIG. 1C is a sectional view taken along line XX of FIG. .

The substrate 10 of the diamond-coated cutting tool according to the first embodiment has a substantially disk-like shape with the axis O as the center, and the peripheral area of the surface 11 excluding the central area is upward. Convex portion 12 protruding toward
Are formed in plural, for example, four. The plurality of convex portions 12 are arranged at substantially equal intervals in the circumferential direction and have the same shape, and the surface 11 of the substrate 10 is provided.
A flat wall surface 12A that stands upright and faces the front side in the rotation direction T.
Similarly, the direction of rotation T is raised upright from the surface 11 of the substrate 10.
The ridge line intersecting with the flat wall surface 12B facing the rear side is a cutting edge ridge line 13 and has a triangular cross-section. Further, the convex portion 12 is arranged on the surface 11 of the substrate 10 so that the cutting edge ridge line 13 coincides with the direction (radial direction) from the axis O toward the outer peripheral side.

Further, when the cutting edge ridge line 13 of the convex portion 12 is viewed in a cross section along the rotational direction T, that is, in a cross section orthogonal to the extending direction of the cutting edge ridge line 13, as shown in FIG. Become. Here, the angle formed by the direction N orthogonal to the surface 11 of the substrate 10 and the wall surface 12A that is continuous with the front side in the rotation direction T of the cutting edge line 13 and faces the front side in the rotation direction T is θa.
(> 0 °) (For θa, the inclination that the wall surface 12A is directed toward the front side in the rotation direction T from the cutting edge ridge line 13 toward the surface 11 side of the substrate 10 is positive).
Further, the angle formed by the direction N orthogonal to the surface 11 of the substrate 10 and the wall surface 12B which is continuous with the rear side of the cutting edge ridge 13 in the rotation direction T and faces the rear side of the rotation direction T is θb (> 0 °) ( Regarding θb, the inclination of the wall surface 12B toward the rear side in the rotation direction T from the cutting edge ridge line 13 toward the front surface 11 side of the substrate 10 is positive.

Then, these angles θa and θb have the following relationship.・ Θa ≠ θb ・ θa <θb ・ 10 ° ≤θa <45 ° ・ 35 ° ≤θb≤80 ° ・ 45 ° ≤ (θa + θb) ≤90 °

Further, the convex portion 12 is provided with a void 14 which divides the convex portion 12 into a plurality of, for example, two equal parts.
It is formed at a substantially central portion in the longitudinal direction with a predetermined width along a direction (rotational direction T) substantially orthogonal to the longitudinal direction, and the gap 14 is formed.
The bottom surface of the substrate is flush with the surface 11 of the substrate 10. Due to the presence of the voids 14, the cutting edge ridgeline 13 formed on the convex portion 12 is also divided into a plurality of, for example, two, in the radial direction. That is, one convex portion 12 is composed of two convex portions that are equally divided by the void 14.

The substrate 10 on which the plurality of convex portions 12 are arranged is manufactured, for example, by subjecting a flat surface of a substantially disk-shaped substrate to a cutting process or the like.
On the surface 11 of 0, a plurality of convex portions 12 integrated with the surface 11 are formed.

Then, in the substrate 10 as described above, at least the cutting edge ridgeline 13 portion in the convex portion 12 formed integrally with the surface 11 is formed by the vapor phase synthetic diamond 15 to have a layer thickness t of 0.5 to 20 μm. In this embodiment, the plurality of protrusions 12 are coated with
The entire surface 11 of the substrate 10 including is coated with the vapor-phase synthetic diamond 15, and the layer thickness t of the coating layer is, for example, 10 μm.

Such a coating layer of the vapor phase synthetic diamond 15 is applied to the substrate 10 having the plurality of convex portions 12 as described above, for example, by using microwave plasma or by using hot filament. By using the existing method described above, the surface 1 including a plurality of convex portions 12
1 is formed over the entire surface.

Here, regarding the material forming the substrate 10, from the viewpoints of the ease of coating with the vapor phase synthetic diamond 15 and the ease of forming the protrusions 12, for example, the following materials are used. Can be mentioned. Carbide, nitride or carbonitride of a metal or silicon of 4a group, 5a group or 6a group, 4a
Any one of a carbide, a nitride or a carbonitride of silicon and a metal of any one of Group 5a, 6a, and 6a, or a composite thereof. From a composite of at least one of carbides, nitrides or carbonitrides of metals or silicons of groups 4a, 5a and 6a and at least one of iron, nickel or cobalt Cemented carbide. Any one of a nitride or an oxide of silicon or aluminum, or a composite thereof.

The diamond-coated cutting tool configured as described above has the surface 11 of the substrate 10 made of porous resin, rubber, polyurethane rubber (having closed cells) or the like which is rotated around the axis. By pressing it against the surface of the pad with a constant load,
The substrate 10 performs a rotational movement (rotational direction T) in accordance with the rotational movement of the pad, and the surface of the pad is cut by the cutting edge ridges 13 formed on the plurality of convex portions 12 that bite into the pad surface (actually, Means that the vapor-phase synthetic diamond 15 coating the cutting edge ridge 13 cuts the surface of the pad), and the chips generated at this cutting edge ridge 13 radially move along the cutting edge ridge 13. It is discharged through the voids 14 and the like divided into a plurality of parts.

In such a diamond-coated cutting tool, the rotational movement (rotation direction T) of the substrate 10 causes
Wall surface 12A of the convex portion 12 facing the front in the rotation direction T
However, since it comes into contact with the pad surface, this wall surface 1
The inclination angle θa of 2A with respect to the direction N orthogonal to the surface 11 of the substrate 10 determines how well the cutting edge ridge 13 sticks to the pad surface, that is, the amount of cutting the surface of the pad, and the processing speed. Will be a factor in determining. Further, when the surface 11 of the substrate 10 is pressed against the pad surface with a constant load, the wall surfaces 12A and 12B of the convex portion 12 which face the front and rear sides in the rotation direction T come into contact with the pad surface. , Each of the wall surfaces 12A, 12B,
The sum of the inclination angles θa + θb with the direction N orthogonal to the surface 11 of the substrate 10 becomes a factor that determines the amount of cutting edge ridge 13 biting into the pad surface, that is, the depth of cutting of the pad surface by the cutting edge ridge 13. .

Then, by appropriately setting the above-mentioned θa, while adjusting the processing speed to a desired value, by appropriately setting θa + θb in consideration of the previously set θa,
The cutting depth can be adjusted to a desired value, and the pad surface can be efficiently processed and adjusted.

Here, by setting θa <θb, it is possible to maintain the convex portion 12 having an appropriate shape, and conversely, in the case where θa> θb, When θa is set to a certain value and the processing speed is adjusted to a desired value, θb is smaller than θa, so θa + θb cannot be secured sufficiently large in many cases. May have to be set.

By setting 10 ° ≦ θa <45 °, it is possible to maintain both the processing speed and the cutting depth at appropriate values, and this θa is 1
If it is less than 0 °, the processing speed can be increased, but
It may be difficult to secure the size of θa + θb, and it may be unavoidable to set the cutting depth more than necessary. On the other hand, if θa is 45 ° or more, the machining speed may be reduced. . In order to secure the effect as described above, it is preferable that 15 ° ≦ θa ≦ 35 °.

Further, by setting 45 ° ≦ (θa + θb) ≦ 90 °, both the machining speed and the cutting depth can be maintained at appropriate values, and this (θa + θ
If b) is smaller than 45 °, the cutting edge ridge line 13 may be too deep into the pad surface, and there is a risk that the cutting depth will be set to an unnecessarily large amount.
If (θa + θb) is larger than 90 °, the cutting depth on the pad surface due to the cutting edge ridgeline 13 cannot be sufficiently secured, and the machining efficiency may be reduced. In order to secure the effect as described above, it is preferable that 55 ° ≦ (θa + θb) ≦ 75 °.

Furthermore, the cutting edge ridgeline 13 in the convex portion 12
The entire surface 11, including the portion, of the substrate 10 has a layer thickness t of 0.5 to 20 due to the vapor phase synthetic diamond 15.
Since the coating is performed in the range of μm, sufficient wear resistance can be imparted to the cutting edge ridge line 13 and a stable pad can be provided for a long period of time without deteriorating sharpness. The adjusting action can be maintained, and the strength of the convex portion 12 can be further improved. Here, when the layer thickness t of the coating layer of the vapor phase synthetic diamond 15 is smaller than 0.5 μm,
The abrasion resistance given to the cutting edge ridgeline 13 becomes insufficient, and on the other hand, when the layer thickness t of the coating layer is larger than 20 μm, the coating layer becomes brittle and cracks are likely to occur. In order to make the above effects more reliable, the vapor phase synthetic diamond 1
The layer thickness t of the coating layer 5 is preferably set in the range of 2 to 10 μm.

In addition, for example, during CMP polishing of a semiconductor wafer, at the same time when the pad surface for polishing the semiconductor wafer is processed and adjusted, the material forming the substrate 10 of the diamond coating cutting tool is eluted. By doing so, there is a risk of contamination of the semiconductor wafer. Therefore, for the substrate 10, a material such as, among the materials constituting the substrate 10 described above, which is less likely to be contaminated by elution is used. Often. However, in the diamond-coated cutting tool according to the present embodiment, since the coating layer of the vapor-phase synthetic diamond 15 is formed over the entire surface 11 of the substrate 10, contamination by elution such as Even if the substrate 10 is made of a material that may be dangerous, there is no fear of such contamination.

Next, the second and third embodiments of the present invention will be described. The same parts as those of the first embodiment described above are designated by the same reference numerals and the description thereof will be omitted. Figure 2 (a) is the second book
3 is a plan view of the diamond-coated cutting tool according to the embodiment, FIG. 3B is an enlarged perspective view of an essential part in FIG.
(A) is a top view of the diamond coating cutting tool by this 3rd Embodiment, (b) is a principal part expanded perspective view in (a).

In the diamond-coated cutting tool according to the second embodiment, in the peripheral region of the surface 11 of the substrate 10, the outer peripheral side portion thereof is provided with, for example, eight convex portions 12 at substantially equal intervals in the circumferential direction. Along with
On the inner peripheral side portion, for example, eight convex portions 12 are formed at substantially equal intervals in the circumferential direction. The cutting edge ridges 13 of the protrusions 12 formed on the outer peripheral side portion of these peripheral regions are arranged so as to extend in the radial direction, and each of the protrusions 12 also formed on the inner peripheral side portion. The cutting edge ridge line 13 is arranged so as to extend in the radial direction, and the cutting edge ridge line 13 of the convex portion 12 on the outer peripheral side portion is arranged.
And the cutting edge ridge line 13 of the convex portion 12 on the inner peripheral side portion are arranged so as not to overlap each other in the radial direction.

The diamond-coated cutting tool according to the third embodiment has a plurality of convex portions 12 arranged in a grid pattern in the peripheral region of the surface 11 of the substrate 10 at substantially equal intervals in the circumferential direction and the radial direction. It has been formed.

Also in each of the diamond coating cutting tools according to the second and third embodiments, the wall surfaces 12A, 1 of the convex portion 12 formed on the surface 11 of the substrate 10 are formed.
The inclination angles θa and θb of 2B are set within the range shown in the above-described first embodiment, and the same effect as in the above-described first embodiment can be obtained.

[0034]

As described above, according to the present invention,
In the convex portion formed on the surface of the substrate, the inclination angle θa (> 0 °) of the wall surface continuous to the front side in the rotation direction of the cutting edge line
And the inclination angle θb (> 0 °) of the wall surface connected to the rear side in the rotational direction of the cutting edge ridge line are θa + θb ≦ 90 ° and θa ≠ θb, so by appropriately setting this θa , Set the processing speed to the desired value, then θa +
Since the cutting depth can be set to a desired value by appropriately setting θb, it becomes possible to individually adjust the machining speed and the cutting depth, and efficient machining can be performed. Further, since the cutting edge ridge portion at least in the convex portion is coated with the vapor-phase synthetic diamond, wear resistance can be imparted to this cutting edge ridge line, so that the sharpness is deteriorated over a long period of time. It is possible to exhibit a stable pad adjusting action.

[Brief description of drawings]

1A is a plan view of a diamond-coated cutting tool according to a first embodiment of the present invention, FIG. 1B is an enlarged perspective view of an essential part in FIG. 1A, and FIG. 1C is a XX line in FIG. FIG.

FIG. 2A is a plan view of a diamond-coated cutting tool according to a second embodiment of the present invention, and FIG. 2B is an enlarged perspective view of essential parts in FIG. 2A.

FIG. 3A is a plan view of a diamond-coated cutting tool according to a third embodiment of the present invention, and FIG. 3B is an enlarged perspective view of essential parts in FIG. 3A.

[Explanation of symbols]

10 Substrate 11 Surface 12 Convex portion 12A Wall surface 12B that is continuous to the front side in the rotational direction of the cutting edge ridge line at the convex portion 12B Wall surface that is continuous to the rear side in the rotational direction of the cutting edge ridge line at the convex portion 13 Cutting edge ridge line 14 Void 15 Gas phase synthetic diamond T rotation Direction t layer thickness N direction orthogonal to the surface of the substrate θa angle orthogonal to the surface of the substrate and the angle θb perpendicular to the surface of the substrate formed by the wall surface that is continuous to the front side in the rotation direction of the cutting edge ridge line in the convex portion, The angle formed by the wall surface that is continuous to the rear side of the cutting edge ridge in the convex direction

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tomoyuki Masuno             1002-14 Mukoyama, Naka-machi, Naka-gun, Ibaraki Prefecture             Terari Co., Ltd.             Inside (72) Inventor Keisuke Morita             1002-14 Mukoyama, Naka-machi, Naka-gun, Ibaraki Prefecture             Terari Co., Ltd.             Inside F-term (reference) 3C047 EE18 EE19

Claims (6)

[Claims] 1. A plurality of convex portions having cutting edge ridges are provided on a surface of a substantially disk-shaped substrate which is rotated around an axis, and the cutting edge ridges are viewed in a cross section along a rotation direction. An angle θ formed by a wall surface that extends in a direction orthogonal to the surface of the substrate and a wall surface that is continuous to the front side in the rotation direction of the cutting edge line in the convex portion.
The relationship between a (> 0 °) and the angle θb (> 0 °) formed by the wall surface that is continuous with the direction orthogonal to the surface of the substrate and is located on the rear side in the rotation direction of the cutting edge ridge line in the convex portion is θa + θb.
≦ 90 ° and θa ≠ θb, and further, at least the cutting edge ridge line portion in the convex portion is
Diamond coated cutting tool characterized by being coated with vapor phase synthetic diamond. 2. The diamond-coated cutting tool according to claim 1, wherein θa <θb. 3. The diamond-coated cutting tool according to claim 1 or 2, wherein 10 ° ≦ θa <45 °. 4. The diamond coating cutting tool according to claim 1, wherein 45 ° ≦ (θa + θb) is satisfied. 5. The diamond-coated cutting tool according to claim 1, wherein the coating layer of the vapor-phase synthetic diamond has a layer thickness of:
A diamond-coated cutting tool characterized by being set in a range of 0.5 to 20 μm. 6. The diamond-coated cutting tool according to claim 1, wherein the entire surface of the substrate is coated with the vapor-phase synthetic diamond. tool.