WO2007023949A1 - Tool with sintered body polishing surface and method of manufacturing the same - Google Patents

Abstract

An efficiently processible polishing tool, particularly used for a CMP pad conditioner, capable solving problems in a fixing strength for fixing abrasive grains to a base plate and problems in nonuniform polished surface and a method of effectively manufacturing the polishing tool. The polishing tool (1) comprises a polishing part formed of a super abrasive grain sintered body sintered integrally with the lining material of a cemented carbide. The polishing part comprises a plurality of polishing units (2) with top parts. The top parts are positioned on an approximately same plane. The polishing units (2) are formed by forming a linear groove (3) group in the polishing part.

Description

 Specification

 Tool having sintered body polishing portion and method for manufacturing the same

 Technical field

 The present invention relates to a tool having a sintered body polishing part and a method for manufacturing the tool. In particular, the present invention is applicable to chemical mechanical polishing (abbreviated as CMP) pads composed mainly of hard urethane and polishing tools capable of processing various semiconductor materials with high flatness and high efficiency. And an effective manufacturing method thereof.

 Background art

 In recent years, CMP has been used for planarization of metal film wafers such as an interlayer insulating film as the number of wiring layers in VLSI devices has increased. In order to maintain the high flatness of the polishing pad (generally made of rigid foam polyurethane) used in CMP and the wafer polishing rate, it is necessary to condition the surface of the polishing pad constantly or intermittently.

 [0003] Conventionally, when this polishing pad is conditioned, a tool in which diamond barrels are fixed to a substrate by electrodeposition has been used. As an example of such an electrodeposition-type conditioning tool, a hollow area in which no bullets are arranged is located at the center of the circular surface of the disk-shaped base, the first being outside, and the outside being further outside. Each of the second abrasive layer regions is provided, and the first abrasive layer region is provided with a plurality of rows of small munition layer portions spaced from each other, and each of the blast particle layer portions has a substantially partial spherical shape. In the bulge surface, the super-abrasive particles are fixed with a metal plating phase, and the second particle layer area is fixed to the ring-shaped circumferential ridges with a metal plating phase. Such a rotary polishing tool is known (Patent Document 1).

 Such electrodeposition type tools are not always satisfactory in holding power because the abrasive grains are only physically fixed to the substrate by the electrodeposited nickel. The grains dropped out and there was room for improvement in tool life.

[0004] Further, there is a known polishing tool having an abrasive layer in which a ball of diamond isotropic force is fixed on a circular rotation plane with a resin bond material, and radial and concentric slits are provided on the surface of the abrasive layer. Yes (Patent Document 2). However, the retention strength of the barrel with resin bond material is not always satisfactory! Therefore, depending on the application, a sufficient tool life could not be obtained, and the electrodeposition tool was not at a satisfactory level.

 [0005] Further, a dresser is known in which a polycrystalline diamond thin film is formed on a working surface of a base metal having a convex portion by a vapor phase synthesis method (Patent Document 3).

 However, it is difficult to form a diamond thin film faithfully to the small unevenness of the base metal by the vapor phase synthesis method, so that sufficient accuracy cannot be obtained, and the bonding force between the thin film and the base metal is sufficient. I can't say that.

[0006] The conventional polishing tool (pad conditioner) as described above has a structure in which a plurality of abrasive grains having different particle diameters are fixed to a substrate (base metal), so that uniform abrasive grains (vertex) are used. Since the level is difficult to obtain, the conditioning process uses only the particles that protrude the most from the substrate (base metal) surface, resulting in intense consumption of these particles that are subjected to excessive loads. Often disabled before the end of its life.

[0007] If a wafer made of silicon or the like can be covered with a tool in which a super-abrasive such as diamond is fixed to the surface of a base metal made of rigid metal, regardless of the polishing pad made of urethane foam and the free barrel, This is desirable because it saves time and money for conditioning, but for this to happen, a superabrasive layer of diamond, such as diamond, which is placed on the base metal and forms the cutting edge, has a high precision plane and retains it. It must be possible. However, such a tool was not fully realized.

 Patent Document 1: Japanese Patent Laid-Open No. 2002-337050

 Patent Document 2: JP 2004-291184 A

 Patent Document 3: Japanese Patent Laid-Open No. 10-0771559

 Disclosure of the invention

 Problems to be solved by the invention

[0008] An object of the present invention is to provide a polishing tool capable of high-efficiency machining that solves the problem of the adhesion strength of the bullets to the substrate, the problem of the uneven polishing surface, and the like, and an effective manufacturing method thereof. It is in this. In particular, it is to provide a polishing tool capable of processing a surface of a semiconductor wafer or the like with high accuracy and high efficiency as a CMP pad conditioner. Means for solving the problem

 [0009] The present inventor has intensively studied to solve the above-described problems, and in addition to a polishing tool having a polishing portion made of a superabrasive sintered body, a plurality of polishing units specific to the polishing portion. As a result of further research, it has been found that the present invention can be completed.

 That is, the present invention is a polishing tool having a polishing portion that also has super-abrasive sintered body strength, wherein the polishing portion includes a plurality of polishing units having a top portion, and each top portion is substantially on the same plane. It relates to a polishing tool.

 Further, the present invention is such that the polishing portion is made of a superabrasive sintered body integrated with a cemented carbide backing material, and the polishing unit is formed by providing a linear groove group in the polishing portion. The present invention relates to the polishing tool.

 Moreover, this invention relates to the said grinding | polishing tool by which blade attachment is performed to the top part. Furthermore, the present invention relates to the polishing tool, wherein the polishing unit is a quadrangular pyramid or a truncated pyramid.

 [0010] The present invention also relates to the above polishing tool, wherein the polishing unit has a quadrangular pyramid shape, and at least one side of the top is bladed.

 Furthermore, the present invention relates to the polishing tool, wherein the polishing unit is a triangular pyramid shape or a triangular frustum shape.

 The present invention also relates to the above polishing tool, wherein the polishing unit has a triangular frustum shape, and at least one side of the top is bladed.

 Furthermore, the present invention relates to the polishing tool, wherein the polishing unit has a shape exhibiting a linear ridge line at the top.

 In the present invention, the polishing unit is a quadrangular pyramid or a triangular pyramid, and the pitch force si of the polishing unit is

It is related with the said polishing tool which is 500 micrometers or less 200 micrometers or more.

 Further, in the present invention, the polishing unit has a quadrangular pyramid shape or a triangular pyramid shape, and the height force of the polishing unit is

00 μm or less The present polishing tool is 30 μm or more.

The present invention also relates to the polishing tool as described above, wherein the super-particles are diamond. Furthermore, the present invention relates to the above polishing agent, wherein the diamond has a nominal particle size of 40-60 / zm or less. Concerning ingredients.

 The present invention also relates to the polishing tool described above, wherein the thickness of the super-abrasive sintered body is 0.1 mm or more.

 Furthermore, this invention relates to the said grinding | polishing tool which is disk shape or annular | circular shape.

[0011] The present invention also relates to the above polishing tool, wherein the polishing section is disc-shaped or annular.

 Furthermore, the present invention relates to the above polishing tool, wherein the polishing section has an outer diameter of 90 mm or more. The present invention also relates to the polishing tool, wherein the height of the top with respect to the bottom of the groove of the polishing part is 1 mm or less.

 Furthermore, the present invention relates to the above polishing tool, wherein the polishing part is composed of two or four divided polishing parts, and each of the divided polishing parts has a fan shape having the same central angle.

 Further, according to the present invention, the divided polishing portion has two groove groups, the first groove group is provided parallel to the radial edge of the divided polishing portion, and the second groove group is orthogonal to the first groove group. It is related with the said grinding | polishing tool currently formed.

 Furthermore, the present invention relates to the above polishing tool, wherein the polishing part has a force of 3 or 6 divided polishing parts, and each of the divided polishing parts has a fan shape having the same central angle.

 Further, according to the present invention, the divided polishing portion has three groove groups, the first groove group is provided in parallel to the radial edge of the divided polishing portion, and the second groove group and the third groove group are: The present invention relates to the above polishing tool, which is formed so as to intersect at 60 ° and 120 ° with respect to the first groove group, respectively.

 Furthermore, the present invention relates to the polishing tool, wherein the groove is formed by wire-cut electric discharge machining.

 The present invention also relates to the above polishing tool, which is a CMP pad conditioner.

[0012] Furthermore, the present invention relates to a method for producing a polishing tool having a polishing part having a super-agglomerate sintered body strength,

 (1) A process of sintering and superimposing superabrasive grains on a cemented carbide backing material to obtain a superabrasive sintered body,

(2) a step of flattening a polishing portion of the obtained superabrasive sintered body,

(3) A process of providing a group of linear grooves in a flattened superabrasive sintered body to form a plurality of polishing units to form a polishing portion It is related with the said manufacturing method containing.

 The present invention also relates to a method for manufacturing an abrasive tool having an abrasive part having super-abrasive sintered body strength.

(1) A process of sintering and superimposing superabrasive grains on a cemented carbide backing material to obtain a superabrasive sintered body,

(2) From the obtained superabrasive sintered body, a step of cutting out one fan-shaped divided polishing portion,

(3) a step of obtaining a plurality of fan-shaped divided polished portions, such as U and the central angle of the fan-shaped divided polished portions obtained in (2) above,

 (4) a step of sticking the obtained fan-shaped divided polishing portions on a flat substrate surface in close contact with each other to form a disk-shaped or annular polishing portion;

 (5) A step of forming a plurality of polishing units by providing a groove at the boundary between the divided polishing portions of the disk-shaped or annular polishing portion obtained in (4).

 It is related with the said manufacturing method containing.

 Furthermore, the present invention relates to the method for regenerating a polishing tool according to any one of the above, comprising the step of regenerating the grooves and the top of the polishing unit by wire-cut electric discharge machining.

 The invention's effect

 [0013] The polishing tool of the present invention uses a polishing portion having super-atomized sintered body strength, and is sintered at a temperature equal to or higher than the melting temperature of the binder, so that the fixing strength of the super-atomized particles is substantially increased. There is an advantage that there is no dropout. In particular, when diamond particles are used as super-ejections, diamond is subjected to temperature and pressure conditions in which the binder metal melts and the diamond is thermodynamically stable in the manufacturing process, and the diamond fine particles become the binder metal. Due to the strong integration through partial dissolution, the fixing strength is further increased, and virtually no dropout occurs.

[0014] In general, when sintering is performed over a large area, unevenness is generated, and it is difficult to produce an overall uniform polished portion with a large diameter. A polishing tool for manufacturing a bonded body is a large-diameter polishing part by cutting out a large-diameter fan-shaped divided polishing part from a small-diameter super-abrasive sintered body that does not cause unevenness of sintering and combining a plurality of these parts. Therefore, it is possible to obtain a highly accurate polishing tool that is homogeneous throughout. [0015] Further, since the polishing portion in which the polishing unit is formed is composed of a superabrasive sintered body having a sufficient thickness on the surface, even if the polishing unit is worn out by use, the wire cut discharge is performed. The groove and polishing unit can be easily regenerated by heating and reused as the tool of the present invention.

[0016] In the present invention, each polishing unit is arbitrarily cut by a super-abrasive sintered body force, such as a diamond sintered body, by a wire cut discharge cage, such as a triangular pyramid and a quadrangular pyramid. Since it is easy to control the bottom surface level and height, a tool having a polishing surface (level) with higher accuracy than a conventional polishing tool can be obtained. In particular, as a CMP pad conditioner, the surface of a semiconductor wafer can be processed with high accuracy and high efficiency.

 Brief Description of Drawings

 FIG. 1 is an explanatory view (plan view) showing an embodiment of a polishing tool according to the present invention. (Example 1)

 FIG. 2 is an explanatory view (plan view) showing an embodiment of a polishing tool according to the present invention. (Example 2)

 FIG. 3 is an explanatory view (plan view) showing an embodiment of a polishing tool according to the present invention.

 FIG. 4 is an explanatory view (plan view) showing an embodiment of a polishing tool according to the present invention.

 FIG. 5 is a partially enlarged view of FIG.

 FIG. 6 is a partially enlarged view of FIG.

 FIG. 7 is an explanatory view (plan view) showing an example of the configuration of the polishing unit of the polishing tool according to the present invention.

 FIG. 8 is an explanatory view showing a cross section taken along line AA in FIG.

 FIG. 9 is an explanatory view (plan view) showing another configuration example according to the polishing unit of the polishing tool according to the present invention.

 FIG. 10 is an explanatory view showing a cross section taken along line BB in FIG. 9.

 FIG. 11 is an explanatory view showing an embodiment of wire-cut electric discharge machining that can be used in the manufacturing method of the polishing tool according to the present invention.

 FIG. 12 is an explanatory view (plan view) showing an embodiment of a polishing tool according to the present invention.

FIG. 13 is an explanatory view (plan view) showing one embodiment of a polishing tool according to the present invention. 14] An explanatory view (plan view) showing an embodiment of the polishing tool according to the present invention.

FIG. 15 is an explanatory view (plan view) showing an embodiment of a polishing tool according to the present invention.

FIG. 16 is an explanatory view (plan view) showing an embodiment of a polishing tool according to the present invention.

FIG. 17 is an explanatory view (plan view) showing an embodiment of a polishing tool according to the present invention. Explanation of symbols

 1 Polishing tool

 2 Polishing unit

 3 groove

 4 Abrasive tools

 5 Polishing unit

 6 groove

 7 Abrasive tools

 8 Polishing unit

 9 groove

 10 Polishing part

 12 First direction parallel groove group

 13, 14 Conical side

 16 Second direction parallel groove group

 17, 18 Cone inclined side

 19 Square pyramid (table) polishing unit

 22 First direction parallel groove group

 23, 24 Triangular pyramid inclined surface

 25 Polishing part

 27 Second parallel groove group

 28, 29 Inclined side

 31 Third direction parallel groove group

 32, 33 inclined side

34 Triangular pyramid polishing unit Wire for discharging force grinding Polishing part, .44 Polishing unit Polishing part Circular substrate Straight groove group Second groove group Peripheral inclined part Polishing part Circular substrate Linear groove group Second groove group Third groove group Peripheral inclined part Inner peripheral slope Part Polishing part Circular substrate Straight groove group Joint part Second groove group Polishing part Circular substrate Linear groove group Joint part Second groove group Polishing part Circular substrate Linear groove group 95 Second groove group

 96 Third groove group

 101 Polishing part

 102 Circular substrate

 103 Linear groove group

 104 joints

 105 Second groove group

 106 Third groove group

 BEST MODE FOR CARRYING OUT THE INVENTION

[0019] The super-agglomerate sintered body as the material of the polishing tool of the present invention is obtained by treating super-agglomerate powder such as diamond or cBN (cubic boron nitride) in an ultra-high pressure and high-temperature process by a conventional method. It is done. Since the sintered body in this state has a large distortion, the sintered body is preliminarily flattened by die discharge machining. Next, the grooves and the side surfaces of the protrusions are formed stepwise in a manner specified by the present invention, thereby creating a polishing unit, that is, a protrusion portion that directly contacts the object to be polished. When a commercially available product is used as the superabrasive sintered body, although depending on the specification, the surface is flattened, the above-described preplanarization treatment can be omitted.

 For the formation of the groove, wire cutting electric discharge machining, die electric discharge machining, other precision electric discharge machining, or laser machining can be used. Wire cutting electric discharge force is preferable, and the top of the polishing unit is preferred. Wire-cut electric discharge machining is particularly preferred when sharpening sharp edges. Wire cutting is a technique in which a wire for electric discharge machining is driven along the surface of the super-abrasive sintered body, and the material is removed by electric discharge between the metal wire and the super-encapsulated sintered body material. Is done.

In the polishing tool of the present invention, the polishing unit is, for example, a plurality of groove groups (hereinafter referred to as divided groove groups) for dividing a polishing surface into an annular sintered body layer having a circular or concentric central circular hole. Can also be created by die-cutting using an electrode having an electrode surface formed in a corresponding shape. Regardless of whether the segment groove group is formed on the surface of the superabrasive layer or the electrode surface, it is easy to make it straight. [0021] The dividing groove group can be variously arranged. As an example, on the circular surface of the super-orbital layer, two sets of parallel straight line groups extending to the outer periphery on the opposite side from the outer periphery are formed perpendicular to each other (Fig. 1), and There are three pairs of straight lines intersected at 60 ° (Fig. 2). In these cases, square or triangular polishing units are created, respectively. In addition, the shape of the polishing unit has a linear ridge line at the top (FIG. 3; the polishing unit exhibits a ridge line to the end of the polishing part, FIGS. 4 to 5; the base of the polishing unit is rectangular), etc. It's okay. When the polishing unit is rectangular, the groove and the inclined surface of the adjacent polishing unit are formed by wire-cut electric discharge machining, so that the ridge line is basically formed parallel to the long side. In addition, the quadrangular pyramid-shaped polishing units do not necessarily have the same vertical and horizontal pitches, but the CMP conditioner is preferably a square.

 [0022] In the above example, in order for each polishing unit to function as an effective polishing portion, the top of each polishing unit is sufficiently small, and adjacent polishing units are separated from each other with sufficient spacing. It is necessary. As an example regarding the area of the top of the polishing unit, FIG. 6 schematically shows a partially enlarged explanatory view of the polishing tool 1 of FIG. 1.For example, the area (X) of the base of the polishing unit 2 (that is, superabrasive grains) The ratio of the top area (Y) to the area of the layer cross section minus the area of the groove 3 around the polishing unit) is preferably 50% or less, particularly preferably 2 to 25%. . The apex angle of the top of the polishing unit is preferably 30 to 120 °, particularly preferably 60 to 90 °, and still more preferably about 70 to 80 °.

 [0023] The depth of the groove (height of the polishing unit from the groove bottom) is suitably 0.1 mm or more and lmm or less, particularly 0.15 mm or more and 0.3 mm or less. If the groove is too shallow, the shavings of the work material will not be discharged efficiently, and the polishing resistance will tend to be excessive. On the other hand, if the depth is too deep, the strength of the polishing unit will be insufficient, and an excessive super-atomized layer thickness will be required.

 [0024] The polishing unit is formed as a polygonal column with a top or a straight line, a line segment, a triangle, a square or more, and each side surface is perpendicular to the substrate, and the horizontal cross section is uniform over the entire height. However, it is possible to improve sharpness by inclining at least one side surface, particularly the front side surface with respect to the direction of rotation of the tool, backward with respect to the plane parallel to the axis.

As the shape of the polishing unit, each side surface of the polishing unit is inclined to form a frustum, for example, a square. A frustum shape or a triangular frustum shape is preferable. Furthermore, the shape of a pyramid, for example, a quadrangular pyramid or a triangular pyramid is particularly preferable in terms of sharpness.

 Also, in aligned prismatic or pyramidal polishing units, one or more sides of a rectangle or triangle are polished with a dedicated tool to sharpen the edges or vertices of the top, so-called “blading”. If done, a better sharpness can be achieved. In particular, when the polishing unit force is a polygonal column or a polygonal frustum, and the top is a polygon (typically a triangle or a quadrangle), cutting is performed on at least one side of the top surface. In the case of a quadrangular pyramid shape or a triangular pyramid shape, sufficient sharpness can be achieved without cutting.

 [0025] The polishing part of the present invention has an outer diameter of 90 mm or more and a superabrasive layer thickness of 0.1 mm to 1 mm. As a sintered superabrasive layer, one side of a diamond sintered body (PCD) or c-BN sintered body (Pc BN) is bonded to a cemented carbide, that is, a tungsten carbide based composite material or a group 6a of the periodic table. Use a structure backed by a composite block composed mainly of metal carbide. Adhere the composite side to the tool substrate with an adhesive, etc., and form a section groove on the opposite side to use as a polishing part. .

 [0026] As such a sintered body, a disk-shaped one typically prepared by a uniaxial pressurization type high-temperature ultrahigh-pressure hydrostatic press is commercially available. When a sintered body having a desired diameter is not available, the abrasive tool of the present invention may be prepared for each part and assembled and used as a single abrasive tool when particularly severe flatness is not required.

 [0027] When the polishing unit is composed of a plurality of divided polishing units, grooves are formed at the boundary between the divided polishing units in order to obtain an arrangement in which the polishing units are evenly aligned as much as possible in the entire polishing unit. Is appropriate. At this time, if two groups of parallel grooves intersecting at right angles to each other are formed in the two or four divided polishing portions and the polishing unit is a quadrangular pyramid or a truncated pyramid shape, polishing without disturbance except for the outer peripheral portion. Unit alignment is obtained. On the other hand, in the case of a three- or six-part divided polishing section, three sets of equally-spaced parallel straight lines intersecting each other at 120 ° are formed, and three pyramid side surfaces are formed to form a triangular pyramid or triangular pyramid. The same applies to the trapezoidal polishing unit row.

That is, in the case of a quadrangular pyramid, a wire for electric discharge machining is sent along the surface of the polished portion and released. First, linear grooves are formed on the surface of the polished portion by electricity. Next, by driving the shear in the Z-axis direction of the polishing portion and cutting the polishing portion along the side surface contour of the quadrangular pyramid, the side surface of the cone-shaped body adjacent to the groove is created. By repeating this operation, parallel groove groups are formed.

 In the present invention, the top of the cone is composed of one or a plurality of diamond particles.

 Even with fine particles, diamond has a finite size, so a cone in the geometric sense cannot be obtained. Therefore, when the top diameter is sufficiently small compared to the bottom, this is called a cone. As is obvious, the frustum is a case where the size of each apex is larger than that of the cone.

 In the production of the quadrangular pyramid (pedestal) -shaped polishing unit, for example, as shown in FIGS. 7 and 8, a group of parallel grooves in the first direction 11 at a constant groove interval (pitch) on the surface of the polished portion 10. (One of which is typically indicated by reference numeral 12 and so on) and conical (pedestal) -like body side surfaces (one of which is indicated by reference numerals 13 and 14 and so on). Rotate 90 ° around the center axis of the ring together with the substrate to which the substrate is fixed, and in the same manner, parallel groove groups 16 in the second direction 15 are arranged at a constant groove interval, and the cone inclined side surface adjacent to each groove, 17 18, two sets of parallel groove groups orthogonal to each other and a quadrangular pyramid-shaped polishing unit 19 aligned along the grooves are obtained. A cross-sectional view of the A—A portion in Fig. 7 is shown.

 In the case of a triangular pyramid, as shown in FIGS. 9 and 10, in the above, after forming the parallel groove group 22 in the first direction 21 and the inclined surfaces 23 and 24 of the pyramid adjacent to the groove, polishing is performed. The part 20 is rotated 120 ° around the central axis of the polishing part 25. Similarly, the formation of the parallel groove group 27 in the second direction 26 and the adjacent inclined side faces 28, 29 at a constant groove interval by wire-cut electric discharge machining. Do. After the operation was completed, the polishing part was further rotated 120 ° and the same operation was performed, so that the parallel grooves 31 in the third direction 30 intersecting at 120 ° and the adjacent inclined side surfaces 32 and 33 were aligned along the grooves. Triangular pyramid polishing unit 34 is obtained.

[0032] In the above polishing unit, it is appropriate that the protruding height of the top of the cone or frustum to the groove bottom is 200 m or less and 30 m or more for both the triangle and the quadrangle. If the protrusion is too shallow, the polishing body itself comes into direct contact with the work such as a pad, and conditioning tends not to be performed effectively. On the other hand, if it is too large, the strength of the polishing unit will be insufficient or excessive. The thickness of the super-abrasive layer is required. On the other hand, the interval (pitch) between adjacent grooves can be 1500 m or less, and the lower limit can be a force due to the diameter of the wire for the wire-cut discharge cage to be used, for example, about 200 / zm.

 [0033] The polishing performance of the above-mentioned polishing unit depends on the particle size of the super-cannon contained in the top of the cone-shaped body. When the superabrasive grains are diamond particles, that is, when the sintered body constituting the polished part is a sintered diamond (PCD) layer, the diamond particle size (nominal particle size) is 40-60 μm or less, 8 Forces that PCD layers of various particle sizes such as -16 μm and 0-2 μm can be used Nominal particle size of 8-16 μm or less is preferred, and 0-2 μm is particularly preferable.

 [0034] The diamond sintered body that can be used in the polishing portion of the present invention comprises diamond particles that are thermodynamically bonded together with a cemented carbide as a backing material and, if necessary, a binder metal such as a core. It is obtained by subjecting it to stable ultra-high pressure and high temperature conditions. Processing from the sintered body to the polishing portion of the present invention can be realized by precision electric discharge machining, typically cut out by wire cut electric discharge machining, and formation of a polishing unit by surface processing. In wire-cut discharge Karoe, in general, an electric discharge machining wire is brought into contact with a superabrasive sintered body and discharged, the wire is moved horizontally so as to obtain a desired groove width, and the side surface of the polishing unit is further moved. Move to form.

 In addition, as shown in FIG. 11, after the discharge force wire 41 is applied to the super-abrasive sintered body 42 and then moved horizontally, it is moved in the direction of the arrow in FIG. It is also possible to form a groove so that both inclined surfaces facing each other become the contact surface of the wire 41, and this level can be used as a reference surface to form both side surfaces. When the groove is formed in this way, the shape of the bottom of the groove is a curved surface having a substantially arc-shaped cross section, and stress concentration during polishing is reduced and the polishing unit is reduced compared to the case where the bottom of the groove is flat or square. Strength (durability) is improved.

[0035] The tool of the present invention can be manufactured in several shapes as illustrated in FIGS.

For relatively small tools, for example, the polishing part can be made in a single continuous circle and an annular shape as illustrated in FIGS. 12 and 13, but in the present invention, as shown in FIGS. Since the polishing portion can be configured with a plurality of divided polishing portions without any problem, an annular polishing portion having a large outer diameter of 95 mm or more can be easily obtained particularly in these cases. [0036] In an annular configuration, the radial width is preferably 15 mm or more. In particular, when the central hole is not required by design, the polished portion can be a disc shape (without a central hole) instead of an annular shape. Also, as shown in Fig. 12 and Fig. 13, in order to prevent the workpiece from being damaged due to contact with the sharp edges, the outer peripheral part of the circular polishing part and the outer peripheral part and the inner peripheral part of the annular polishing part, respectively. It is preferred to provide ramps 58, 68 and 69 over lmm (radial width)! /.

 [0037] When the polishing unit is composed of a plurality of divided polishing units, as illustrated in FIGS.

By setting the polishing unit arrangement so that the boundary part (joint part) between two adjacent divided polishing parts becomes a groove, the polishing unit arrangement is disturbed by the divided structure of the polishing part, and the workpiece (polishing pad) associated therewith ) Can be avoided or minimized. At this time, the number of divisions of the polishing part and the shape of the available polishing units are related. In Fig. 15), the tri-section (center angle 120 °) polished part has a triangular pyramid shape (Figs. 16 and 17).

 [0038] In order to produce a large-diameter polishing tool, cutting to a predetermined size and shape from a small-diameter super-encapsulated sintered body (preferably a diamond sintered body) capable of uniform sintering. Then, a divided polishing part formed by heating is prepared. A plurality of divided polished parts are bonded to a flat disk surface or an annular surface of a rigid substrate made of various steels using an adhesive or the like, so that a large-diameter disk shape or an annular shape is joined. A polishing portion (a shape having a concentric circular hole in the center of the disk) can be obtained.

 For the division polishing part, use 6, 4, 3, or 2 fan sections with a central angle of 60, 90, 120, 180 ° adjacent to each other on the radius side by side (side contact arrangement) However, instead of using two of the same shape for the 60 ° one, one 120 ° one can be substituted. In this case, two 120 ° ones are arranged symmetrically with respect to the center.

 [0039] Each polishing part 51, 61, 71, 81, 91, 101 joins the cemented carbide side to the flat circular surface of the circular substrate 52, 62, 72, 82, 92, 102, and is generally circular. Or make it present an annular polished part.

[0040] The superabrasive sintered body bonded to the substrate is then subjected to wire-cut electric discharge machining in the following manner, and the superabrasive sintered body is subjected to an electric discharge process between the wire-force electric discharge machining wire and the superabrasive sintered body. Surface of sintered powder A set of linear groove groups 53, 63, 73, 83, 93, 103 which are parallel to each other at regular intervals are formed. At this time, the wire is driven parallel to the substrate surface or the substrate bottom surface and enters the sintered body layer (typically a sintered diamond (PCD) layer) from a pre-planarized surface. The sintered body layer is further carved into a cemented carbide layer if the sintered body layer is thin.

[0041] At this time, the wire is driven and cut in the thickness direction (Z-axis direction) of the super-orbital sintered body to form a groove. The first groove formation in one groove group can be started at any position force in either a triangular pyramid or a quadrangular pyramid on a 360 ° continuous circular or annular surface. If this is the case, the joints 54, 64, 74, 84, 94, and 104 of the divided polishing part are always provided with grooves, and then on both sides, with a constant pitch and parallel to the entire surface. To form.

 [0042] When parallel groove groups in one direction are formed on the surface of the superabrasive sintered body, the superabrasive sintered body is then rotated together with the substrate around the central axis of the substrate by the groove group crossing angle OC. Similarly, the second linear parallel groove group 55, 65, 75, 85, 95, 105 and the inclined side surface adjacent to each groove are formed at the above-mentioned fixed intervals. Here, α is 90 ° for 180 ° and 90 ° fan shapes, and the polishing unit has a quadrangular pyramid shape or frustum shape. On the other hand, for the 120 ° and 60 ° sectors, after rotating by 60 or 120) °, the second linear parallel groove group and the inclined side surface adjacent to each groove are formed at the same regular intervals. And another 60 or 120) ° (240 ° with respect to the first groove group) and adjacent to the third linear parallel groove group 56, 66, 76, 86, 96, 106 and each groove. An inclined side surface is formed. For continuous circular and annular materials, α can be either 90 ° or 60 °.

 [0043] In the wire cut discharge operation, the groove and the triangular or quadrangular pyramid or frustum-like body are obtained by driving the discharge wire at a height (level) in which the substrate bottom surface force is equally spaced in the thickness direction. Can be formed on a level parallel to the bottom surface of the substrate.

[0044] In the present invention, the triangular pyramid or the quadrangular pyramid of the polishing unit does not necessarily need to be entirely composed of a superabrasive sintered body, and at least about 60 m including the apex of the cone-shaped body. If this part (height) is a super-abrasive sintered body, it can be used even if the lower part is a cemented carbide. Next, the present invention will be specifically described with reference to examples. [Example 1]

 [0045] A polishing tool 1 having a structure schematically shown in FIG. 1 was prepared. A PCD block with a diameter of 90 mm was used as a tool material, in which a sintered diamond layer with a thickness of 0.6 mm was integrated with cemented carbide by simultaneous sintering.

 In the above PCD block, the surface of the sintered diamond layer is flattened by an electric discharge cage (EDM), and a polishing unit 2 having a square top of 260 m on one side is obtained by a wire cut electric discharge cage. It was formed by engraving parallel linear grooves 3 having a width of 560 m. In this case, the area of the top portion (not shown) of the polishing unit 2 corresponds to about 10% of the cross-sectional area of the super-abrasive sintered layer excluding the peripheral portion (the groove 3 portion).

 The top edge was edged and used as a CMP conditioner.

 [Example 2]

 An annular polishing tool 4 schematically shown in FIG. 2 was produced. 0.6mm thick sintered c BN layer is integrally formed with cemented carbide by simultaneous sintering. From a PcBN block, wire cut discharge calorie, 90 ° fan with 60mm outer radius and 24mm inner radius. 4 molds were cut out and used as a tool material The above fan mold was attached to a SUS stainless steel substrate and combined into a complete circle. The surface of the sintered diamond layer is polished and flattened, and by wire-cut electric discharge machining, a polishing unit 5 having an apex of an equilateral triangle with a side of 350 μm is formed into a parallel straight groove 6 with a width of 560 μm. Formed in groups. In this case, the area of the top of the polishing unit is 7% of the entire superabrasive sintered layer. The obtained tool was bladed by the same operation as in Example 1 and used for polishing the surface of the silicon wafer.

 [Example 3]

 A polishing tool having the structure schematically shown in FIG. 12 was prepared. Polished diamond sintered body with a diameter of 100 mm, with a diamond particle force of nominal particle size of 40-60 μm and a 0.5 mm thick PCD layer integrated with cemented carbide (WC—8% Co) by simultaneous sintering This was used as a part and fixed to an SUS316 stainless steel circular substrate having a diameter of 108 mm with an epoxy adhesive.

Next, the surface of the PCD layer was flattened with a mold discharge cage and then cut into the PCD layer with a wire cut discharge cage to form a straight groove having a width of 200 m passing through the center of the material. Further wires Driving to the side and moving in a direction away from the substrate (z direction), a groove having a necessary width was formed and the side surface of the cone was cut out.

 By repeating this operation, parallel groove groups with a groove interval of 800 m and roof-like protrusions with an apex angle of 90 ° were formed on the entire material surface.

 Next, after rotating the whole around the central axis by 90 °, wire cutting discharge is performed under the same conditions to form a second linear groove group orthogonal to the above groove group, and at the same time The sides of the cones in the orthogonal direction were cut out to form a group of quadrangular pyramids as shown in Figs. 7 and 8 with a height of 200 m.

 [Example 4]

 [0048] Using a diamond sintered body with an outer diameter of 100 mm and an inner diameter of 70 mm as a polishing part, in which a 0.5 mm thick PCD layer composed of diamond particles with a nominal particle size of 0-2 μm is integrated with cemented carbide The operation of Example 3 was repeated to produce a polishing tool having a quadrangular pyramid-shaped polishing unit. First, the surface of the flat PCD layer was wire-cut discharge force, and a straight groove with a width of 140 μm passing through the center of the material was formed. Furthermore, the necessary groove width was expanded and the side surfaces of the cones were cut out by manipulating the wires. By repeating this, a group of parallel grooves with a groove interval of 200 m and a roof-like protrusion with an apex angle of 60 ° were formed on the entire material surface.

 Next, after rotating the whole 90 ° around the central axis, the second straight groove group is formed by performing wire cut discharge heating under the same conditions, and at the same time, the side surface of the second conical body is formed. Cut out to form a group of quadrangular pyramids with a height of 200 m.

 [Example 5]

 [0049] Tools having the respective configurations were produced using the following various types of divided polishing portions. All diamond diamonds have a nominal grain size of 20-30 m. The wire-cut operation is essentially the same for triangular pyramid polishing units, except that the tool material is rotated twice by 60 °, differing from a square pyramid polishing unit that rotates 90 ° only once. Not different. The operating conditions and results are shown in the following table.

[0050] [Table 1] Polishing body Polishing unit

No. Groove spacing

 Outer radius Inner radius

 Shape (Vertex spacing Shape i¾ m

 m m ΠΊ ΠΊ tl m

 1 1 80 ° Fan 120 60 600 Square pyramid 80

2 1 20 ° Fan 120 60 400 Triangular pyramid 68

3 90 ° Fan 120 60 1200 Square pyramid 160

4 6CT Fan 120 30 1000 Triangular pyramid 138

, The apex interval is 2 or 4 triangular pyramid

[0051] All of the obtained tools were used as CMP pad conditioners, and good performance was obtained.

 Industrial applicability

[0052] The polishing tool of the present invention can be used as various types of polishing tools, but can be particularly suitably used as a disk-type rotary polishing tool. As an application, it is particularly suitable for use as a CMP pad conditioner, and is also suitable for directly polishing the surface of a semiconductor wafer or the like. In addition to these, it can be applied to high-precision polishing of various work materials.

Claims

The scope of the claims  [I] A polishing tool having a polishing part having super-abrasive sintered body strength, wherein the polishing part includes a plurality of polishing units having a top part, and the top parts are substantially flush with each other.  [2] The polishing portion is made of a super-agglomerated sintered body that is sintered and integrated with a cemented carbide backing material, and the polishing unit force is formed by providing a group of linear grooves in the polishing portion. The polishing tool according to claim 1.  [3] The polishing tool according to claim 1 or 2, wherein the top is bladed.  [4] The polishing tool according to claim 1 or 2, wherein the polishing unit is a quadrangular pyramid or a truncated pyramid.  [5] The polishing tool according to claim 4, wherein the polishing unit has a quadrangular frustum shape, and at least one side of the top is bladed. [6] The polishing tool according to claim 1 or 2, wherein the polishing unit is a triangular pyramid shape or a triangular frustum shape.  [7] The polishing tool according to claim 6, wherein the polishing unit has a triangular frustum shape, and at least one side of the top is bladed. [8] The polishing tool according to claim 1 or 2, wherein the polishing unit has a shape having a linear ridge line at the top.  [9] The polishing tool according to any one of claims 1 to 7, wherein the polishing unit is a quadrangular pyramid shape or a triangular pyramid shape, and the pitch of the polishing unit is 1500 m or less and 200 m or more.  10. The polishing tool according to claim 9, wherein the polishing unit is a quadrangular pyramid shape or a triangular pyramid shape, and the height of the polishing unit is 200 m or less and 30 m or more.  [II] The polishing tool according to any one of claims 1 to 10, wherein the super-ejection is diamond. [12] The polishing tool according to claim 11, wherein the nominal grain size of the diamond is 40-60 μm or less. [13] The polishing tool according to any one of [1] to [12], wherein the thickness of the super-agglomerated sintered body is 0.1 mm or more.  [14] The polishing tool according to any one of [1] to [13], which is disc-shaped or annular. 15. The polishing tool according to claim 14, wherein the polishing part is disk-shaped or annular. 16. The polishing tool according to claim 15, wherein the outer diameter of the polishing part is 90 mm or more. [17] The polishing tool according to any one of [2] to [16], wherein the height force of the top with respect to the bottom of the groove of the polishing portion is Slmm or less.  [18] The polishing tool according to any one of [14] to [17], wherein the polishing portion is composed of two or four divided polishing portions, and each of the divided polishing portions has a fan shape having an equal central angle.  [19] The divided polishing portion has two groove groups, the first groove group is provided parallel to the radial edge of the divided polishing portion, and the second groove group is orthogonal to the first groove group. The polishing tool according to claim 18, wherein the polishing tool is formed.  [20] The polishing tool according to any one of [14] to [17], wherein the polishing portion comprises three or six divided polishing portions, and each of the divided polishing portions has a fan shape having an equal central angle.  [21] The divided polishing portion has three groove groups, the first groove group is provided parallel to the radial edge of the divided polishing portion, and the second groove group and the third groove group are respectively 21. The polishing tool according to claim 20, wherein the polishing tool is formed so as to intersect at 60 ° and 120 ° with respect to the groove group.  [22] The polishing tool according to any one of [2] to [21], wherein the groove is formed by wire-cut electric discharge machining.  [23] The polishing tool according to any one of claims 1 to 22, which is a CMP pad conditioner. [24] A method for producing a polishing tool having a polishing portion made of a super-agglomerate sintered body,  (1) A process of sintering and superimposing superabrasive grains on a cemented carbide backing material to obtain a superabrasive sintered body, (2) a step of flattening a polishing portion of the obtained superabrasive sintered body,  (3) A process of providing a group of linear grooves in a flattened superabrasive sintered body, forming a plurality of polishing units, and forming a polishing portion  The said manufacturing method including. [25] A method of manufacturing a polishing tool having a polishing portion with super-abrasive sintered strength,  (1) A process of sintering and superimposing superabrasive grains on a cemented carbide backing material to obtain a superabrasive sintered body, (2) From the obtained superabrasive sintered body, a step of cutting out one fan-shaped divided polishing portion, (3) a step of obtaining a plurality of fan-shaped divided polished portions, such as U and the central angle of the fan-shaped divided polished portions obtained in (2) above, (4) a step of sticking the obtained fan-shaped divided polishing portions on a flat substrate surface in close contact with each other to form a disk-shaped or annular polishing portion; (5) A step of forming a plurality of polishing units by providing a groove at the boundary between the divided polishing portions of the disk-shaped or annular polishing portion obtained in (4). The said manufacturing method including.  24. The method for regenerating a polishing tool according to claim 1, comprising a step of regenerating the groove and the top of the polishing unit by wire cut electric discharge machining.