JPH11277407A - Polishing pad, polishing device, and polishing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polishing pad for chamical-mechanical polishing, capable of surely holding polishing slurry, and increasing the chance to make the polishing slurry contact with a wafer to improve the quality of polishing, and a polishing device, a polishing method using the polishing pad. SOLUTION: With a disc-like polishing pad for use in polishing process by chemical-mechanical polishing method, a recessed part 23 is formed in the polishing pad. At least a part of the bottom part 23b of the recessed part 23 is positioned on the outer peripheral side relative to an opening part 23a of the recessed part 23 or on the reverse side (A side) to the direction of rotation of the polishing pad, and at least a side wall 23c on the outer peripheral side of the recessed part 23 or on the reverse side to the direction of rotation of the polishing pad, is formed to be reversely tapered in relation to the surface of the polishing pad.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chemical mechanical polishing (CMP) in a semiconductor device manufacturing process.
The present invention relates to a polishing pad used for performing a planarization process of an interlayer insulating film by an ical polishing method, a polishing apparatus using the polishing pad, and a polishing method.

[0002]

2. Description of the Related Art In recent years, the miniaturization and high integration of semiconductor integrated circuits have progressed to the next generation in three years, and the design rules have been reduced by 70% of the previous generation. Has also been realized. In order to process a semiconductor device finely, for example, the gate width of a gate electrode of a transistor or the DR
It is necessary to reduce the area occupied by capacitors in AM, etc., and also to make the wiring part a multi-layer wiring structure. Is becoming important. As devices such as transistors and capacitors have a complicated structure and become three-dimensional, an interlayer insulating film has become thicker.

[0003] The above miniaturization has advanced the fine processing technology in the manufacturing process of semiconductor devices, and in particular, the technology of transferring a circuit pattern to a photosensitive organic film (photoresist) coated on a wafer surface using light. Has been achieved by increasing the resolution in the lithography process. Specifically, the light source used in the lithography process has a shorter wavelength. For example, a g line (436 nm) or i
Line (365 nm) is used, and i-line is mainly used for pattern transfer according to the 0.35 μm rule. In addition, for manufacturing a semiconductor integrated circuit having a rule of 0.25 μm or later, a technique of exposing using a KrF excimer laser (248.8 nm) or an ArF excimer laser (193 nm) has been developed.

[0004] As described above, the improvement of the resolution in the lithography step causes a decrease in the depth of focus (DOF) of the exposure in the lithography step. This improvement has to wait for the improvement of the resist performance, but the improvement of the resist performance is preceded by the demand for miniaturization. Therefore, a method of compensating for the lack of the depth of focus by minimizing the height difference of the device structure when performing the lithography process and reliably resolving a fine pattern without causing defocus has been studied.

Therefore, as a method of flattening the height difference of the device structure, recently, a chemical mechanical polishing method applying mirror finishing of a silicon wafer has been adopted. FIG.
FIG. 1 is a schematic view showing a conventional chemical mechanical polishing apparatus for performing this chemical mechanical polishing. This apparatus is used to sharpen the surface of a polishing pad 2 in which a polishing plate 3 supported on a rotating polishing plate rotating shaft 1 and having a polishing pad 2 adhered to a surface thereof, and a die 102 and the like formed by electrodeposition on a metal plate. A dresser 101, a carrier 5 holding a substrate 4 (hereinafter, referred to as a wafer) on which a layer to be polished such as an interlayer insulating film is formed by a wafer backing film 14, and a polishing slurry 10 are supplied onto the polishing pad 2. And a polishing slurry supply device 7 having a polishing slurry supply nozzle 6.

After dressing (grinding) the polishing pad 2 with a dresser 101, the polishing plate rotating shaft 1 and the carrier rotating shaft 8 are rotated, and the polishing slurry 10 is supplied from the polishing slurry supply nozzle 6 to the center of the polishing pad 2.
While the wafer 4 is being supplied,
Is pressed onto the polishing pad 2 to polish the wafer 4.

However, in the above-described chemical mechanical polishing method, there is a problem that the polishing rate varies greatly between wafers and the polishing amount varies greatly within the wafer surface.

In order to reduce the variation in the polishing rate between wafers and the variation in the polishing amount in the wafer surface, it is necessary to supply the polishing slurry to the wafer stably and uniformly in the wafer surface. come. As a principle of the chemical mechanical polishing, a dresser makes countless scratches on the surface of the polishing pad 2 to form a so-called shallow dressing layer in which fine hairs stand on the surface of the polishing pad 2. By polishing the wafer 4 in a state where the polishing slurry 10 enters and is held, the polishing slurry can be sufficiently supplied to the polishing surface of the wafer 4 pressed against the polishing pad 2,
Thus, polishing can be performed. In consideration of this, dressing of the polishing pad surface by a dresser, so-called dressing, is sufficiently performed so that the depth and density of the dressing layer are sufficient, and a sufficient amount of polishing slurry 1 is formed on the surface of the wafer 4.
Make sure 0 arrives. As described above, measures are taken to reduce the variation in the polishing rate between wafers and the variation in the polishing amount in the wafer surface.

[0009]

However, when a dressing layer is formed on the pad surface by dressing as described above and the polishing slurry is supplied and the wafer is polished, the wafer is pressed against the polishing pad. Since the polishing slurry was extruded from the polishing pad from the fine hair, the above-mentioned object could not be sufficiently achieved.

In order to solve the above problem, conventionally, as shown in FIG. 6, for example, a lattice-shaped groove 21 is cut in a polishing pad 20 and a polishing slurry is accumulated there to increase the chance of contact with a wafer. Attempts have been made. However, the above structure has a problem in that the polishing slurry is efficiently discharged to the outside of the polishing pad by passing through the lattice-shaped grooves, and the expensive polishing slurry is wasted.

To improve the above problem, a polishing pad in which a concentric groove 22 is cut with respect to the center of the polishing pad 20 as shown in FIG. 7 has been considered. However, even in this case, the polishing slurry accumulated in the groove 22 due to the centrifugal force of the polishing pad is actually discharged to the outside of the polishing pad except for remaining on the outer peripheral side of the groove 22, and the chance of contact of the polishing slurry with the wafer is reduced. With little increase, the above problems remained.

As described above, the fact that the polishing slurry is discharged from the polishing pad without being effectively utilized increases the cost of chemical mechanical polishing, and the polishing slurry does not sufficiently contribute to polishing. There is a problem in that there is a concern that the polishing quality is deteriorated due to a variation in the rate between wafers and a variation in the polishing amount in the wafer surface.

The present invention has been made in view of the above-mentioned problems. Accordingly, the present invention provides a conventional method for chemical mechanical polishing in which an interlayer insulating film is planarized in a semiconductor device manufacturing process. In addition to forming the dressing layer of the polishing pad by dressing the pad with a dresser, the polishing slurry is securely held without increasing the process cost, and the chance of contact of the polishing slurry with the wafer is increased, thereby reducing the polishing rate. A polishing pad for chemical mechanical polishing capable of suppressing variations between wafers and a variation in a polishing amount within a wafer surface and improving polishing quality, and a polishing apparatus using the same. An object of the present invention is to provide a polishing method.

[0014]

In order to achieve the above object, a polishing pad of the present invention is a disk-shaped polishing pad used for a polishing process by a chemical mechanical polishing method, wherein the polishing pad has a concave portion. Is formed, at least a part of the bottom of the concave portion is located on the outer peripheral side or the opposite side of the rotation direction of the polishing pad from the opening of the concave portion, and at least the outer peripheral side of the concave portion or the polishing pad. The side wall on the opposite side of the rotation direction is formed in a reverse taper shape with respect to the polishing pad surface.

In the above polishing pad of the present invention, at least a part of the bottom of the recess formed in the disc-shaped polishing pad is located on the outer peripheral side or the opposite side of the rotation direction of the polishing pad from the opening of the recess. Since at least the outer peripheral side of the concave portion or the side wall on the opposite side in the rotation direction of the polishing pad is formed in an inversely tapered shape with respect to the polishing pad surface, the polishing slurry is reliably held without increasing the process cost, By increasing the chance of the polishing slurry contacting the wafer, it is possible to suppress the variation in the polishing rate between wafers, the variation in the polishing amount in the wafer surface, and the like, and to improve the polishing quality.

The above polishing pad of the present invention is preferably
The entire bottom of the concave portion is formed so as to be located on the outer peripheral side of the opening of the concave portion or on the opposite side in the rotation direction of the polishing pad. This makes it possible to more reliably hold the polishing slurry.

The above polishing pad of the present invention is preferably
The recess is a hole having a substantially circular opening, and more preferably, a plurality of the holes are formed. Thereby, it is possible to form a concave portion formed in the polishing pad, and it is possible to more reliably hold the polishing slurry by forming a plurality of holes. As the above holes,
It is shaped to extend from the surface of the polishing pad to the inside of the polishing pad toward the outer periphery of the polishing pad, or the outer periphery of the polishing pad from the surface of the polishing pad to the inside of the polishing pad. On the side,
Further, the polishing pad may have a shape extending in a direction opposite to a rotation direction of the polishing pad.

The above polishing pad of the present invention is preferably
The recess is a groove. Thereby, it can be set as the concave part formed in the above-mentioned polishing pad. As the groove, a shape that is concentric with the rotation center of the polishing pad, or a groove extending in a substantially radial shape from the rotation center of the polishing pad, at least at the polishing pad outer peripheral end portion of the groove, At least a part or the entirety of the bottom of the groove may be formed so as to be located on the opposite side of the opening direction of the groove from the direction of rotation of the polishing pad.

The above polishing pad of the present invention is preferably
A plurality of the concave portions are formed, and a communication groove connecting the concave portions is formed inside the polishing pad. Alternatively, preferably, the opening of the recess is formed so as to extend at least on the rotation center side of the polishing pad or on the rotation direction side of the polishing pad over the bottom of the recess. Alternatively, preferably, the area of the opening of the recess is larger than the area of the bottom of the recess. This makes it easier for the polishing slurry to enter the concave portion, and allows the polishing slurry to be held efficiently.

The above polishing pad of the present invention is preferably
The polishing pad is formed of a material selected from urethane, silicone rubber, hard rubber, Teflon, nylon, vinyl chloride, and a mixture thereof. By forming from such a porous material, it is possible to efficiently hold the polishing slurry. In addition, as the polishing pad material, in order to more easily hold the polishing slurry, it is also possible to employ, for example, a urethane material in a sponge state or the like having a large foam size or amount or both, but in this case, the hardness of the polishing pad Is reduced, the flatness of the entire polished surface of the wafer after the polishing process is deteriorated, and when a foaming material is used for the polishing pad, during the actual polishing process, due to the pressing pressure of the wafer, Since the polishing pad is crushed and the polishing slurry is squeezed out,
Since the holding of the polishing slurry is not so high, the polishing pad itself needs to have at least hardness and elasticity required for polishing. According to the above materials, it is also possible to impart hardness and elasticity required for polishing, so that it is possible to improve polishing quality such as improving flatness on the entire polished surface of a wafer after polishing. It is.

In order to achieve the above object, a polishing pad according to the present invention is a belt-shaped polishing pad used for a polishing process by a chemical mechanical polishing method, wherein a concave portion is formed in the polishing pad. Wherein at least a part of the bottom of the recess is located in a direction opposite to the direction of travel of the polishing pad with respect to the opening of the recess, and a side wall of the recess opposite to the direction of travel of the polishing pad is formed of the polishing pad. It is formed in a reverse tapered shape with respect to the surface.

In the above polishing pad of the present invention, at least a part of the bottom of the concave portion formed in the belt-shaped polishing pad is located on the opposite side of the opening direction of the concave portion in the direction of travel of the polishing pad. Since the side wall on the opposite side of the traveling direction is formed in a reverse taper shape with respect to the polishing pad surface,
Without increasing the process cost, hold the polishing slurry securely, increase the chance of the polishing slurry contacting the wafer, and reduce the variation in polishing rate between wafers and the variation in polishing amount within the wafer surface. Thus, the polishing quality can be improved.

The above object can be achieved by the above-described polishing apparatus and method using the polishing pad of the present invention.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic view showing a chemical mechanical polishing apparatus according to the present invention. This apparatus sharpens the surface of a polishing pad 2 which is supported by a rotating polishing plate rotating shaft 1 and has a disk-shaped polishing pad 2 adhered to the surface, and a die 102 and the like formed by electrodeposition on a metal plate. And a carrier 5 for holding a substrate 4 (hereinafter, referred to as a wafer) on which a layer to be polished such as an interlayer insulating film is formed by a wafer backing film 14.
A polishing slurry supply device 7 having a polishing slurry supply nozzle 6 for supplying the polishing slurry 10 onto the polishing pad 2 is generally constituted.

After dressing (grinding) the polishing pad 2 by the dresser 101, the polishing plate rotating shaft 1 and the carrier rotating shaft 8 are rotated, and the polishing slurry 10 is supplied from the polishing slurry supply nozzle 6 to the center of the polishing pad 2.
While the wafer 4 is being supplied,
Is pressed onto the polishing pad 2 to polish the wafer 4.

The polishing pad 2 will be described. As shown in the cross section of FIG.
And at least a part of the bottom 23b of the concave portion 23 is located on the outer peripheral side or the opposite side to the rotation direction of the polishing pad with respect to the opening 23a of the concave portion, and is located on the outer peripheral side of the concave portion or the rotational direction of the polishing pad. The opposite side wall 23c is formed in an inverse tapered shape with respect to the polishing pad surface. Here, the outer peripheral side of the polishing pad or the opposite side to the rotation direction of the polishing pad is indicated by a direction A, and the direction of the rotation center of the polishing pad or the rotation direction of the polishing pad is indicated by a direction B.

According to the polishing pad of the present embodiment,
Bottom 23b of recess 23 formed in disc-shaped polishing pad
Is located on the outer peripheral side of the opening 23a of the concave portion 23 or on the opposite side of the polishing pad rotation direction (direction A in the figure), and the outer peripheral side of the concave portion or the side wall 23 on the opposite side of the polishing pad rotational direction.
Since c is formed in a reverse taper shape with respect to the polishing pad surface, the polishing slurry is reliably held without increasing the process cost, and the chance of contact of the polishing slurry with the wafer is increased, and the polishing rate is increased. It is possible to suppress the variation between wafers and the variation in the polishing amount within the wafer surface, and to improve the polishing quality.

The polishing pad 2 is made of, for example, a material selected from urethane, silicone rubber, hard rubber, Teflon, nylon, vinyl chloride and a mixture thereof. By forming from such a porous material, it is possible to efficiently hold the polishing slurry. By using the above materials as the material of the polishing pad, it becomes possible to provide the hardness and elasticity required for polishing, so that the polishing efficiency is increased, and the polishing is performed by increasing the flatness of the entire polished surface of the wafer. It is possible to improve the quality.

The recess formed in the polishing pad can be, for example, a hole having a substantially circular opening, and a plurality of holes can be formed. The hole may have a shape extending from the surface of the polishing pad to the inside of the polishing pad, or extending from the surface of the polishing pad to the inside of the polishing pad. And a shape extending in a direction opposite to the rotation direction of the polishing pad.

The recess formed in the polishing pad may be, for example, a groove. The groove may have a shape concentric with the center of rotation of the polishing pad, or may have a shape corresponding to the rotation of the polishing pad. A groove extending in a substantially radial shape from the center, and at least a part or all of the bottom of the groove is located on the opposite side in the rotation direction of the polishing pad from the opening of the groove at least at the outer peripheral end portion of the polishing pad. Can be formed.

Further, the concave portion formed in the polishing pad may have a shape in which a plurality of concave portions are formed and a connecting groove connecting the concave portions is formed inside the polishing pad. In addition, the opening of the recess may be formed so as to be wider than the bottom of the recess at least on the rotation center side of the polishing pad or on the rotation direction side of the polishing pad. In addition, the shape may be such that the area of the opening of the recess is larger than the area of the bottom of the recess.

In the present embodiment, the polishing pad is not limited to the disk shape, but may be a belt shape depending on the configuration of the polishing apparatus. In this case, at least a part of the bottom of the concave portion formed in the polishing pad is located on the opposite side of the opening direction of the concave portion in the traveling direction of the polishing pad, and the side wall on the opposite side in the traveling direction of the polishing pad is on the polishing pad surface. On the other hand, by making the tapered shape inverse, it is possible to obtain the same effect as the above-mentioned disk-shaped polishing pad.

First Embodiment FIG. 3A is a plan view showing a pattern of holes formed in a polishing pad according to this embodiment. Holes 24 having a substantially circular opening are formed in the disk-shaped polishing pad substrate 20 so as to be arranged four by four radially from the center of rotation 210 thereof. Here, each hole 24 extends from the surface of the polishing pad to the inside of the polishing pad toward the outer peripheral side of the polishing pad, and is formed to open in the direction of arrow 25.
In the figure, the direction of rotation of the polishing pad is indicated by an arrow 30.

FIG. 3B is a sectional view taken along line XX 'in FIG. 3A. A hole 24 is formed in the polishing pad substrate 20, and the bottom 24 b of the hole 24 is
4a, the outer peripheral side wall 24 of the hole 24
c is a reverse tapered shape with respect to the polishing pad surface,
It is formed in a shape extending from the surface of the polishing pad to the inside of the polishing pad toward the outer peripheral side of the polishing pad. As described above, since each hole 24 is formed so as to be inclined with respect to the polishing pad substrate 20, the supplied polishing slurry near the rotation center 210 of the polishing pad is centrifuged by the rotation of the polishing pad in the direction 30. Upon receiving the force, the polishing slurry flows out toward the outer peripheral side of the polishing pad. At this time, the polishing slurry flows into the hole 24 opened in the polishing pad and fills the hole 24. In the case of a hole formed perpendicular to the polishing pad substrate, the polishing slurry easily flows out again from the hole, but the side wall 24c on the outer peripheral side of the hole 24 has an inverted taper shape with respect to the polishing pad surface. As a result, the polishing slurry held in the holes 24 is less likely to flow out again, so that the polishing slurry is reliably held, the chance of contact of the polishing slurry with the wafer is increased, and the polishing rate between the wafers is reduced. Variations and variations in the amount of polishing within the wafer surface can be suppressed, and the polishing quality can be improved.

Second Embodiment FIG. 4A is a plan view showing a pattern of holes formed in a polishing pad according to this embodiment. Holes 26 having a substantially circular opening are formed in the disk-shaped polishing pad substrate 20 so as to be arranged four by four radially from the center of rotation 210 thereof. Here, each hole 26 extends from the surface of the polishing pad to the inside of the polishing pad on the outer peripheral side of the polishing pad and in the direction opposite to the rotation direction 30 of the polishing pad, and is formed to open in the direction of arrow 27. Have been.

FIG. 4B is a sectional view taken along line XX 'in FIG. 4A. A hole 26 is formed in the polishing pad substrate 20, and the bottom 26 b of the hole 26 is
6a, the outer peripheral side of the hole 26 and the side wall 26c on the opposite side in the rotational direction of the polishing pad are reversely tapered with respect to the polishing pad surface. It is formed in a shape extending toward the outer peripheral side of the polishing pad and in the direction opposite to the rotation direction of the polishing pad. According to the polishing pad of the present embodiment, similarly to the first embodiment, the polishing slurry is securely held, the chance of the polishing slurry contacting the wafer is increased, and the polishing rate varies between wafers and the polishing amount. It is possible to suppress the variation in the wafer surface and the like, and to improve the polishing quality.

Third Embodiment FIG. 5A is a plan view showing a pattern of grooves formed on a polishing pad according to this embodiment. A groove 28 having a shape concentric with a center of rotation 210 is formed in the disk-shaped polishing pad base 20. Here, groove 2
Numeral 8 extends toward the outer periphery of the polishing pad from the surface of the polishing pad to the inside of the polishing pad, and is formed to open toward the rotation center 210 of the polishing pad.

FIG. 5B is a sectional view taken along line XX ′ in FIG. 5A. A groove 28 is formed in the polishing pad base 20, and the bottom 28 b of the groove 28 is located on the outer peripheral side of the opening 28 a of the groove 28, and the side wall 2 on the outer peripheral side of the groove 28 is formed.
8c is formed in a reverse tapered shape with respect to the polishing pad surface. According to the polishing pad of the present embodiment, similarly to the first embodiment, the polishing slurry is securely held, the chance of the polishing slurry contacting the wafer is increased, and the polishing rate varies between wafers and the polishing amount. It is possible to suppress the variation in the wafer surface and the like, and to improve the polishing quality.

The present invention is not limited to the above embodiment and examples. For example, in the first and second embodiments described above, the polishing pad substrate is radiated from the center of rotation by four.
The holes are formed one by one, but the number is not limited to four and may be any number. However, it is possible to more surely hold the polishing slurry by forming a plurality. In the third embodiment, one groove is formed, but two or more grooves may be formed. In addition, various changes can be made without departing from the spirit of the present invention.

[0041]

As described above, according to the polishing pad of the present invention, in chemical mechanical polishing for flattening an interlayer insulating film in a semiconductor device manufacturing process, dressing of a pad by a conventional dresser is performed. In addition to forming the dressing layer of the polishing pad, the polishing slurry is securely held without increasing the process cost, the chance of the polishing slurry contacting the wafer is increased, and the polishing rate varies between wafers. In addition, it is possible to suppress variations in the amount of polishing within the wafer surface, and to improve the polishing quality.

Further, the polishing pad of the present invention can be used by being incorporated in a polishing apparatus, and the substrate to be processed can be polished by using the polishing apparatus. It is possible to improve the polishing quality by increasing the chance of the polishing slurry contacting the wafer, suppressing the variation in the polishing rate between the wafers and the variation in the polishing amount in the wafer surface, and the like. .

[Brief description of the drawings]

FIG. 1 is a schematic view of a chemical mechanical polishing apparatus according to the present invention and a conventional example.

FIG. 2 is a sectional view showing a shape of a concave portion formed in the polishing pad according to the embodiment of the present invention.

FIG. 3A is a plan view showing a pattern of holes formed in the polishing pad according to the first embodiment.
FIG. 3B is a cross-sectional view taken along line XX ′ in FIG.

FIG. 4A is a plan view showing a pattern of holes formed in a polishing pad according to a second embodiment; FIG.
FIG. 4B is a cross-sectional view taken along line XX ′ in FIG.

FIG. 5A is a plan view showing a pattern of grooves formed on a polishing pad according to a third embodiment, and FIG.
FIG. 5B is a cross-sectional view taken along line XX ′ in FIG.

FIG. 6 is a plan view showing a pattern of grooves formed in a polishing pad according to a first conventional example.

FIG. 7 is a plan view showing a pattern of grooves formed in a polishing pad according to a second conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Polishing plate rotating shaft, 2 ... Polishing pad, 3 ... Polishing plate, 4 ... Substrate to be processed (wafer), 5 ... Carrier,
6: polishing slurry supply nozzle, 7: polishing slurry supply device,
8 Carrier rotating shaft 9 Polishing pressure adjustment mechanism 10 Polishing slurry 11 Dresser applied pressure 14 Wafer backing film 20 Polishing pad base 21
2, 28 groove, 23 recess, 24, 26 hole, 23a,
24a, 26a, 28a ... opening, 23b, 24b, 2
6b, 28b: bottom, 23c, 24c, 26c, 28c
... inverted tapered side walls, 25, 27 ... opening direction of holes,
30: polishing pad rotation direction, 101: dresser, 10
2 ... dresser's diamond, 103 ... dressing dressing layer by dress, 210 ... polishing pad center.

Claims (45)

[Claims] 1. A disk-shaped polishing pad used for a polishing process by a chemical mechanical polishing method, wherein a concave portion is formed in the polishing pad, and at least a part of a bottom of the concave portion is an opening of the concave portion. The outer peripheral side of the portion or the opposite side in the rotation direction of the polishing pad, and at least the outer peripheral side of the concave portion or the side wall in the opposite side of the rotation direction of the polishing pad is formed in a reverse tapered shape with respect to the polishing pad surface. Polishing pad. 2. The polishing pad according to claim 1, wherein the entire bottom of the concave portion is formed so as to be located on the outer peripheral side of the opening of the concave portion or on the opposite side in the rotation direction of the polishing pad. 3. The polishing pad according to claim 1, wherein said recess is a hole having a substantially circular opening. 4. The polishing pad according to claim 3, wherein a plurality of said holes are formed. 5. The polishing pad according to claim 3, wherein said hole has a shape extending from a surface of said polishing pad to an outer peripheral side of said polishing pad as going inside said polishing pad. 6. A shape in which the hole extends from the surface of the polishing pad to the inside of the polishing pad on the outer peripheral side of the polishing pad and in the direction opposite to the rotation direction of the polishing pad. The polishing pad according to claim 3. 7. The polishing pad according to claim 1, wherein said recess is a groove. 8. The polishing pad according to claim 7, wherein said groove is a groove having a shape concentric with the center of rotation of said polishing pad. 9. A groove extending substantially radially from a rotation center of the polishing pad, wherein at least a part of a bottom of the groove at an outer peripheral end portion of the polishing pad has an opening of the groove. The polishing pad according to claim 7, wherein the polishing pad is formed so as to be located on a side opposite to a rotation direction of the polishing pad. 10. The whole of the groove, wherein at least a part of the bottom of the groove is formed so as to be located on a side opposite to the rotation direction of the polishing pad with respect to the opening of the groove. Polishing pad. 11. The polishing pad according to claim 1, wherein a plurality of the concave portions are formed, and a communication groove connecting the concave portions is formed inside the polishing pad. 12. The polishing pad according to claim 1, wherein the opening of the concave portion is formed to extend at least on the rotation center side of the polishing pad or on the rotation direction side of the polishing pad than the bottom portion of the concave portion. 13. The polishing pad according to claim 1, wherein the area of the opening of the recess is larger than the area of the bottom of the recess. 14. The polishing pad according to claim 1, wherein said polishing pad is formed of a material selected from urethane, silicone rubber, hard rubber, Teflon, nylon, vinyl chloride, and a mixture thereof. 15. A belt-like polishing pad used for a polishing process by a chemical mechanical polishing method, wherein a concave portion is formed in the polishing pad, and at least a part of a bottom of the concave portion is an opening of the concave portion. A polishing pad which is located in a direction opposite to a direction in which the polishing pad travels, and wherein a side wall of the concave portion on a side opposite to the direction in which the polishing pad travels is formed in a reverse taper shape with respect to the surface of the polishing pad. 16. A polishing apparatus having a disk-shaped polishing pad for performing a polishing process by a chemical mechanical polishing method, wherein the polishing pad has a concave portion, and at least a part of a bottom portion of the concave portion. Is located on the outer circumferential side or the opposite side of the rotation direction of the polishing pad from the opening of the concave portion, and at least the outer circumferential side of the concave portion or the side wall on the opposite side in the rotational direction of the polishing pad is positioned with respect to the polishing pad surface. Polishing device formed in a reverse tapered shape. 17. The polishing apparatus according to claim 16, wherein the entire bottom of the concave portion is formed so as to be located on the outer peripheral side of the opening of the concave portion or on the opposite side in the rotation direction of the polishing pad. 18. The polishing apparatus according to claim 16, wherein said recess is a hole having a substantially circular opening. 19. The apparatus according to claim 1, wherein a plurality of said holes are formed.
9. The polishing apparatus according to 8. 20. A polishing apparatus according to claim 18, wherein said hole has a shape extending from the surface of said polishing pad to the inside of said polishing pad toward the outer peripheral side of said polishing pad. 21. The hole has a shape extending from the surface of the polishing pad to the inside of the polishing pad on the outer peripheral side of the polishing pad and in the direction opposite to the rotation direction of the polishing pad. The polishing apparatus according to claim 18. 22. The polishing apparatus according to claim 16, wherein said recess is a groove. 23. The polishing apparatus according to claim 22, wherein said groove is a groove having a shape concentric with a rotation center of said polishing pad. 24. The groove is a groove extending in a substantially radial shape from the center of rotation of the polishing pad, and at least a part of a bottom of the groove is an opening of the groove at least at an outer peripheral end portion of the polishing pad. 23. The polishing apparatus according to claim 22, wherein the polishing apparatus is formed so as to be located on a side opposite to a rotation direction of the polishing pad. 25. The groove according to claim 24, wherein at least a part of the bottom of the groove is formed so that at least a part of the groove is located on the opposite side of the opening of the groove in the rotation direction of the polishing pad. Polishing equipment. 26. The polishing apparatus according to claim 16, wherein a plurality of said recesses are formed, and a communication groove connecting said recesses is formed inside said polishing pad. 27. The polishing apparatus according to claim 16, wherein an opening of said concave portion is formed to extend at least on a rotation center side of said polishing pad or on a rotation direction side of said polishing pad with respect to a bottom portion of said concave portion. 28. The polishing apparatus according to claim 16, wherein the area of the opening of the recess is larger than the area of the bottom of the recess. 29. The polishing apparatus according to claim 16, wherein said polishing pad is formed of a material selected from urethane, silicone rubber, hard rubber, Teflon, nylon, vinyl chloride and a mixture thereof. 30. A polishing apparatus having a belt-shaped polishing pad for performing a polishing process by a chemical mechanical polishing method, wherein the polishing pad has a concave portion, and at least a part of a bottom portion of the concave portion. Are located in the direction opposite to the direction of travel of the polishing pad relative to the opening of the recess, and the side wall of the recess on the side opposite to the direction of travel of the polishing pad is formed in an inverse tapered shape with respect to the surface of the polishing pad. Polishing equipment. 31. A polishing method for performing a polishing treatment by a chemical mechanical polishing method using a disk-shaped polishing pad, wherein a concave portion is formed in the polishing pad, and at least a part of a bottom portion of the concave portion is formed. The outer peripheral side of the opening of the concave portion or the opposite side in the rotational direction of the polishing pad, at least the outer peripheral side of the concave portion or the side wall of the polishing pad opposite the rotational direction relative to the polishing pad surface. A polishing method using a polishing pad formed in a reverse taper shape. 32. A polishing pad according to claim 31, wherein a whole of a bottom of said concave portion is formed so as to be located on an outer peripheral side of an opening of said concave portion or on a side opposite to a rotating direction of said polishing pad. Polishing method. 33. The polishing method according to claim 31, wherein said concave portion is a polishing pad having a hole having a substantially circular opening. 34. The polishing method according to claim 33, wherein a polishing pad having a plurality of said holes is used. 35. The polishing method according to claim 33, wherein the polishing pad has a shape in which the hole extends from the surface of the polishing pad to the inside of the polishing pad toward the outer peripheral side of the polishing pad. 36. A shape in which the hole extends from the surface of the polishing pad to the inside of the polishing pad on the outer peripheral side of the polishing pad and in the direction opposite to the rotation direction of the polishing pad. The polishing method according to claim 33, wherein a polishing pad is used. 37. The polishing method according to claim 31, wherein said concave portion is a polishing pad having a groove. 38. The polishing method according to claim 37, wherein said polishing pad is a groove having a shape concentric with the center of rotation of said polishing pad. 39. The groove extending substantially radially from the center of rotation of the polishing pad, and at least a part of the bottom of the groove is formed at least at the outer peripheral end of the polishing pad using the polishing pad. 38. The polishing method according to claim 37, wherein the polishing method is formed so as to be located on a side opposite to a rotation direction of the polishing pad with respect to an opening of the groove. 40. A polishing pad formed so that at least a part of the bottom of the groove is located on the opposite side of the opening of the groove in the rotation direction of the polishing pad in all of the grooves. Item 40. The polishing method according to Item 39. 41. The polishing method according to claim 31, wherein a plurality of the concave portions are formed, and a polishing pad in which a communication groove connecting the concave portions is formed inside the polishing pad. 42. The polishing pad according to claim 31, wherein an opening of said concave portion is formed so as to be wider than a bottom portion of said concave portion at least on the rotation center side of said polishing pad or on the rotation direction side of said polishing pad. Method. 43. The polishing method according to claim 31, wherein a polishing pad is used in which the area of the opening of the recess is larger than the area of the bottom of the recess. 44. The polishing method according to claim 31, wherein said polishing pad is a polishing pad formed of a material selected from urethane, silicone rubber, hard rubber, Teflon, nylon, vinyl chloride and a mixture thereof. 45. A polishing method for performing a polishing treatment by a chemical mechanical polishing method using a belt-shaped polishing pad, wherein a concave portion is formed in the polishing pad, and at least a part of a bottom of the concave portion is formed. The opening of the recess is located in the direction opposite to the direction of travel of the polishing pad relative to the direction of travel of the polishing pad, and the side wall of the recess on the side opposite to the direction of travel of the polishing pad is formed in an inverse tapered shape with respect to the surface of the polishing pad. Polishing method using a polishing pad.