JP2011079076A - Polishing device and polishing method - Google Patents

Abstract

A polishing apparatus capable of cooling a polishing pad while suppressing an influence on polishing is provided.
A polishing pad is affixed to an upper surface, a rotatable turntable, a semiconductor wafer and a top ring that holds the polishing surface of the semiconductor wafer facing the polishing pad. The polishing pad 12 is partitioned into a polishing region 43 in which the top ring 25 disposed in contact with the upper surface and facing the polishing pad 12 is disposed, and a non-polishing region 41 in which the top ring 25 is not disposed. In the radial direction of the polishing pad 12, slurry is supplied to the upper surface of the polishing pad 12 on the side of the separation wall 21 and the polishing region 43 that continuously includes the polishing contact surface 37 formed by the rotating polishing pad 12 contacting the top ring 25. And a cooling medium supply pipe 25 for supplying a cooling medium to the upper surface of the polishing pad 12 in the non-polishing region 41.
[Selection] Figure 1

Description

  The present invention relates to a polishing apparatus and a polishing method used in a CMP method.

  In recent years, in the field of manufacturing semiconductor devices, various fine processing techniques have been used with the increase in density and miniaturization of the devices. Among them, the chemical mechanical polishing (CMP) technique is an indispensable in realizing flattening of interlayer insulating films, formation of plugs, formation of embedded metal wirings and isolation of embedded elements. It became technology.

  In this polishing apparatus that performs CMP, a turntable with a polishing pad attached to the upper surface rotates in a horizontal plane, slurry is supplied from above the polishing pad through a slurry supply pipe, and the slurry wets the entire surface of the polishing pad, A slurry layer is formed on the polishing pad. On this polishing pad, a top ring holding a semiconductor wafer so that the surface to be polished is on the lower side is pressed while rotating in a horizontal plane in the same direction as the turntable. The surface to be polished of the semiconductor wafer is polished by being rubbed against the polishing pad via the slurry.

  Due to the heat generated by this rubbing (friction), the temperature of the surface of the polishing pad rises. The degree of temperature increase increases as the pressing force of the semiconductor wafer against the polishing pad increases, the rotation speed of the top ring or turntable increases, and the slurry flow rate decreases. Moreover, the degree of temperature rise increases as the area of the semiconductor wafer increases.

  This temperature rise depends on CMP conditions and may be several tens of degrees. When the surface temperature of the polishing pad exceeds, for example, 50 ° C. and the surface of the polishing pad softens, there may be a problem that the planarization characteristics in the CMP process deteriorate. Semiconductor wafers are becoming larger in diameter as generations progress. From the viewpoint of cost reduction, the problem of the temperature rise of the polishing pad becomes more serious as the flow rate of the slurry per unit area of the semiconductor wafer is reduced.

  As a countermeasure for this problem, for example, while polishing a semiconductor wafer, if the gas cooled to a predetermined temperature supplied from the cooling gas supply device is ejected from each cooling gas ejection nozzle toward the polishing pad. A polishing apparatus is disclosed in which a portion of the polishing pad used for polishing is cooled to a predetermined temperature immediately before polishing the semiconductor wafer, and therefore the semiconductor wafer is always polished by the surface of the polishing pad at a constant temperature (for example, , See Patent Document 1). In addition to the ejection of the cooled gas, dropping of the cooled liquid and the arrangement of the cooled heat exchange member are disclosed.

  Although the disclosed polishing apparatus can cool the polishing pad, dusting of the dispersed slurry becomes a problem when the gas is blown. In addition, when the liquid is dropped, the dilution of the slurry becomes a problem, and in the heat exchange member, the low cooling efficiency becomes a problem.

JP-A-11-347935

  The present invention provides a polishing apparatus and a polishing method capable of cooling a polishing pad while suppressing the influence on polishing.

  In the polishing apparatus of one embodiment of the present invention, a polishing pad is attached to an upper surface, a rotatable turntable, a polishing target is rotatably held, and a polishing target surface to be polished is disposed opposite to the polishing pad. The polishing pad is divided into a polishing area where the holding means arranged in contact with the upper surface of the polishing pad and opposed to the polishing pad is arranged, and a non-polishing area where the holding means is not arranged, A separation wall continuously including a band of a donut-shaped polishing contact surface formed by the rotating polishing pad in contact with the holding means in the radial direction of the polishing pad in the polishing region; A slurry supply pipe for supplying a slurry to the upper surface of the polishing pad and a cooling medium supply pipe for supplying a cooling medium to the upper surface of the polishing pad in the non-polishing region are provided.

  The polishing method according to another aspect of the present invention divides the polishing pad into a polishing region in which a holding means for a polishing object disposed opposite to a polishing pad is disposed and a non-polishing region in which the holding means is not disposed. Contacting the separation wall with the polishing pad affixed to a turntable; supplying a cooling medium that cools the surface of the polishing pad to the non-polishing region of the rotating polishing pad; and polishing. A step of supplying a slurry to the region; and a step of pressing the rotating polishing object held by the holding unit to the polishing region to which the slurry is supplied.

  ADVANTAGE OF THE INVENTION According to this invention, the grinding | polishing apparatus and the grinding | polishing method which can cool a polishing pad can be provided, suppressing the influence which acts on grinding | polishing.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows typically the grinding | polishing apparatus which concerns on the 1st Embodiment of this invention, FIG. 1 (a) is a front view which shows a part in a cross section (hatching part), FIG. FIG. 1C is a cross-sectional view of the separation wall along the line AA in FIG. 1B. The figure which shows the temperature distribution of the polishing pad of the polishing apparatus which concerns on the 1st Embodiment of this invention. The top view which shows the polishing apparatus which concerns on the 2nd Embodiment of this invention typically, and shows a part in a cross section (hatching part). FIG. 4A is a diagram schematically illustrating a polishing apparatus according to a third embodiment of the present invention, in which FIG. 4A is a front view partially showing a cross section (hatching portion), and FIG. The top view shown by a hatching part. The figure which shows the temperature distribution of the polishing pad of the polishing apparatus which concerns on the 3rd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the figure shown below, the same code | symbol is attached | subjected to the same component.

(First embodiment)
A polishing apparatus and a polishing method according to a first embodiment of the present invention will be described with reference to FIG.

  As shown in FIG. 1, the polishing apparatus 1 is schematically a top that is a holding means for holding a turntable 11, a separation wall 21 that partitions a polishing pad 12 on the turntable 11, and a semiconductor wafer 27 to be polished. A ring 25, a slurry supply pipe 31, and a cooling medium supply pipe 35 are provided. The turntable 11 is housed in a casing 15 in which a funnel 16 is disposed along the outer periphery of the turntable 11.

  The turntable 11 has a size that allows the top ring 25 holding the semiconductor wafer 27 to be accommodated inside the radius. The turntable 11 has a polishing pad 12 attached to the upper surface. The polishing pad 12 is made of, for example, foamed polyurethane, and more specifically, IC1000 / SUBA400 manufactured by Rodel Nitta. The polishing pad 12 of the turntable 11 rotates in a horizontal plane. As shown in FIG. 1B, the rotation direction is, for example, clockwise (shown by an arrow).

  A top ring 25 that holds the semiconductor wafer 27 by suction is disposed above the turntable 11 with the surface to be polished, for example, the semiconductor device surface facing the lower polishing pad 12. The top ring 25 rotates in the same direction as the turntable 11 (shown by an arrow) in a horizontal plane, and is pressed with a constant pressure so that the surface to be polished of the semiconductor wafer 27 is in contact with the surface of the polishing pad 12.

  The top ring 25 has a retainer ring 29 disposed around the semiconductor wafer 27. The retainer ring 29 is intended to prevent the deviation of the semiconductor wafer 27 from the top ring 25 during polishing and to prevent the edge of the semiconductor wafer 27 from being overpolished. However, a configuration in which the retainer ring 29 is not used is also possible.

  At the time of polishing, the polishing pad 12 and the top ring 25 holding the semiconductor wafer 27 are in contact with each other in the region excluding the central portion and the peripheral portion on the polishing pad 12. A locus on the polishing pad 12 formed by the top ring 25 in contact with the polishing pad 12, that is, the polishing contact surface 37 has a donut shape indicated by a dotted line. The polishing contact surface between the polishing pad 12 and the semiconductor wafer 27 is a region included inside the polishing contact surface 37.

  The separation wall 21 has, for example, a U shape in plan view. The U-shaped bottom surface portion of the separation wall 21 is located at the center portion of the polishing pad 12, that is, the position corresponding to the hole inside the doughnut-shaped polishing contact surface 37. The separation wall 21 is curved from the U-shaped bottom surface portion toward the upper end portion, and divides the surface of the polishing pad 12 into a U shape from the center to the outer periphery. The curved separation wall 21 contacts the outer periphery of the polishing pad 12 at two locations in plan view. The separation wall 21 contacts the surface of the polishing pad 12 from directly above. That is, the side surface of the separation wall 21 is substantially perpendicular to the polishing pad 12.

The separation wall 21 is bent outwardly from the surface of the polishing pad 12 in the direction away from the surface of the polishing pad 12 and further in a horizontal crank shape, and two U-shaped upper end portions are formed in the casing 15. It is fixed to. The separation wall 21 is fixed to the casing 15 by, for example, a holding jig 23 provided with a spring so that the separation wall 21 can be pressed uniformly. The pressing load with which the separation wall 21 presses the polishing pad 12 is preferably set to 9.8 kPa (100 gf / cm ² ) or less. This is because when the pressing load is increased, frictional heat between the separation wall 21 and the polishing pad 12 becomes a problem.

  The two locations of the separation wall 21 that are in contact with the outer periphery of the polishing pad 12 are, for example, about 1/4 of the outer periphery of the polishing pad 12. A portion surrounded by about ¼ of the outer periphery of the separation wall 21 and the polishing pad 12 is a region where the top ring 25 is not disposed, that is, a non-polishing region 41. A portion surrounded by about 3/4 of the outer periphery of the separation wall 21 and the polishing pad 12 excluding the non-polishing region 41 is a polishing region 43 in which the top ring 25 is disposed.

  The separation wall 21 has a convex curve toward the upstream in the rotational direction upstream of the polishing pad 12 in the non-polishing region 41, and a convex curve toward the downstream in the rotational direction downstream of the polishing pad 12. Here, the upstream means the side where the rotating polishing pad 12 reaches first in the target region.

  The top ring 25 is generally in a positional relationship facing the non-polishing region 41 with respect to the center of the polishing region 43 along the rotation direction of the polishing pad 12, that is, the center of the polishing pad 12. The top ring 25 and the non-polishing region 41 do not necessarily face the center of the polishing pad 12, and the top ring 25 is disposed upstream of the polishing region 43 in order to prioritize the cooling efficiency of the processing point. It is also possible to arrange them so far as they do not interfere with the separation wall 21.

  As shown in FIG. 1 (c), the cross section of the separation wall 21 is a substantially rectangular shape with a corner at the portion in contact with the polishing pad 12, and the height is such that the cooling medium described later does not flow out above. For example, the width is about 2 cm, and the width is enough to withstand the dynamic friction force received from the rotating polishing pad 12. The material of the separation wall 21 is required to have high chemical resistance and wear resistance, and is equivalent to the retainer ring 29 of the top ring 25, for example, polyetheretherketone (PEEK), polyphenylene sulfide (PPS), polycarbonate. (PC), fluororesin, ceramics and the like can be used. Note that the separation wall 21 can be made of these materials only in the portion in contact with the slurry.

  Above the polishing pad 12 in the polishing area 43, a slurry supply pipe 31 for supplying slurry and a pure water supply pipe 33 for supplying pure water of water polish to the area are provided. The slurry supply pipe 31 and the pure water supply pipe 33 can respectively drop slurry and pure water at positions upstream of the top ring 25 in the rotation direction of the polishing pad 12 and close to the rotation center of the polishing pad 12. is there. The slurry supply pipe 31 and the pure water supply pipe 33 can change the dropping position by moving the dropping port. The slurry differs depending on the object of CMP, and is generally a dispersion of abrasive particles to which a chemical is added, for example, an alumina dispersion to which iron nitrate is added.

  A cooling medium supply pipe 35 with a shower head for supplying a cooling medium is provided above the polishing pad 12 in the non-polishing region 41. The cooling medium supply pipe 35 is provided at a suitable position of the polishing pad 12, for example, a position close to the rotation center, and can spray a cooling medium made of pure water. The reason why the cooling medium is supplied with a porous shower head instead of a single-hole tube is to increase the chance of contact between the cooling medium and the polishing pad 12 and improve the cooling efficiency. When polishing a semiconductor wafer 27 having a relatively small diameter, a single hole cooling medium supply pipe 35 can be used.

  The cooling medium supply pipe 35 can change the supply position by moving the shower head supply port and the supply direction by changing the direction of the shower head supply port. The flow rate of the cooling medium, the temperature of the cooling medium, etc. can be optimized. When lowering the temperature of the cooling medium from room temperature, the cooling medium supply pipe 35 is cooled, for example, by winding a cold heat source (not shown). The cooling medium supply pipe 35 and the shower head moving system, the flow rate control system, the temperature control system, and the like are not shown. The cooling medium may be pure water or water to which a surfactant is added. In this case, it is possible to expect a secondary effect of cleaning the polishing pad 12 that is soiled by the adhesion of the abrasive particles. Further, the cooling medium is not limited to a liquid, and a gas such as nitrogen or air can be used.

  Next, a polishing method using the polishing apparatus 1 will be described.

  As described above, in the polishing apparatus 1, the polishing pad 12 is affixed on the turntable 11, and a U-shaped separation wall 21 that partitions the polishing pad 12 into a non-polishing region 41 and a polishing region 43 includes a pressing jig 23. Is fixed to the casing 15. The separation wall 21 is in contact with the polishing pad 12, and the non-polishing region 41 is continuously secured from the center of the polishing pad 12 in the outer peripheral direction.

The turntable 11 is rotated at a predetermined rotation speed, for example, 60 rpm. Then, the cooling medium is supplied to the non-polishing region 41 defined by the separation wall 21 on the rotating polishing pad 12 through the cooling medium supply pipe 35. The cooling medium spreads from the center of the polishing pad 12 in the non-polishing region 41 to the entire outer peripheral direction. A part of the cooling medium flows to the outer peripheral side due to the centrifugal force generated by the rotation of the polishing pad 12 and falls to the funnel 16. Move along and fall into funnel 16. The flow rate of the cooling medium is, for example, about 200 cm ³ (200 ml / min) per minute.

  Slurry is dropped through the slurry supply pipe 31 to the polishing region 43 defined by the separation wall 21 on the rotating polishing pad 12.

Thereafter, the top ring 25 holding the semiconductor wafer 27 is transported to a position directly above the polishing region 43 and lowered while rotating at a predetermined rotation speed, for example, 63 rpm, and further, a predetermined pressure, for example, 19.6 kPa. The surface to be polished of the semiconductor wafer 27, for example, the semiconductor device surface is brought into contact with the surface of the polishing pad 12 (polishing contact surface 37) by pressing with (200 gf / cm ² ). Polishing proceeds by rubbing the semiconductor device surface of the semiconductor wafer 27 against the polishing pad 12 containing slurry.

  Part of the slurry in the polishing region 43 is caused to flow to the outer peripheral side due to the centrifugal force generated by the rotation of the polishing pad 12 and falls to the funnel 16, but a part of the slurry is downstream of the polishing region 43 (upstream of the non-polishing region 41). 21 and moves along a curved wall surface and is discharged to the funnel 16.

  When the polishing of a predetermined thickness is completed, the supply of the slurry is stopped, and then water polishing is performed by dripping pure water for water polishing from the pure water supply pipe 33, and the slurry adhering to the semiconductor wafer 27 is washed away. When the water polishing is finished, the cooling medium is stopped. However, the cooling medium may be stopped or reduced when the polishing is finished. This is because the load at the time of water polishing is generally smaller than the load at the time of polishing, so that the problem of frictional heat at the time of water polishing is small.

  The semiconductor wafer 27 that has been polished with water after being polished is transferred to a post-cleaning module (not shown) and subjected to post-cleaning processing. Meanwhile, normal dressing is performed on the polishing pad 12 by a dresser (not shown). This dressing is performed by rubbing dressers in the polishing region 43. When dressing is performed after the top ring 25 is retracted, the operating area of the top ring 25 and the operating area of the dresser may overlap. After the dressing is completed, the top ring 25 holding the semiconductor wafer 27 to be polished next is transported to just above the polishing region 43 and is similarly polished.

  Thus, the polishing method of the polishing apparatus 1 provided with the separation wall 21 is basically the same as that of the polishing apparatus without the separation wall 21. However, when the slurry gradually adheres to the separation wall 21 in the polishing region 43 and this deposit falls and reaches below the semiconductor wafer 27 during polishing, a scratch is generated on the surface to be polished of the semiconductor wafer 27. There is a case. Therefore, it is preferable to add this deposit removal process. For example, each time a certain number of semiconductor wafers 27 are processed, it is effective to put a procedure in which the separation wall 21 is lifted from the polishing pad 12 and washed with a hand shower or the like. It is also possible to make a system that can automatically perform such cleaning.

  Next, the effect obtained by CMP using the polishing apparatus 1 will be described.

  Note the temperature distribution on the measurement line 45 (two-dot chain line) close to the top ring 25 on the polishing pad 12 shown in FIG. The measurement line 45 is a line segment included in the polishing contact surface 37 of the radius of the polishing pad 12. Then, it is located downstream of the top ring 25 with respect to the rotation direction of the polishing pad 12. The temperature at the measurement line 45 is measured by a radiation thermometer. Since this temperature is the temperature of the polishing pad 12 immediately after polishing, it can be used as the temperature of the polishing pad 12 directly under the semiconductor wafer 27.

  FIG. 2 is a graph showing the position of the measurement line 45 on the horizontal axis and the temperature on the vertical axis. Without cooling, that is, in a conventional polishing apparatus, this temperature exceeds 50 ° C., and is close to 60 ° C. in the center. On the other hand, with cooling, that is, in the polishing apparatus 1 of this embodiment, this temperature is 40 ° C. or less including the central portion of the polishing contact surface 37. In the polishing apparatus 1, the difference between the maximum temperature and the minimum temperature is also reduced.

  Therefore, without cooling, that is, in the conventional polishing apparatus, the polishing pad 12 is softened due to the temperature rise, so that the planarization characteristics of the polishing are deteriorated, and the global level difference due to the polishing of the semiconductor wafer 27 (the highest and lowest points). The difference in height at the location was as high as 100 nm. On the other hand, in the polishing apparatus 1 of the present embodiment with cooling, since the temperature rise is suppressed, softening of the polishing pad 12 is suppressed, so that the planarization characteristic of polishing is maintained, and globalization due to polishing of the semiconductor wafer 27 is maintained. The level difference (the difference in height between the highest point and the lowest point) is suppressed to 20 nm.

(Second Embodiment)
A polishing apparatus and a polishing method according to a second embodiment of the present invention will be described with reference to FIG. The difference from the polishing apparatus 1 of the first embodiment is that the separation wall has a “<” shape in plan view. In addition, the same code | symbol is attached | subjected to the same component as 1st Embodiment, and the description is abbreviate | omitted.

  As shown in FIG. 3, in the polishing apparatus 2, the separation wall 21 of the polishing apparatus 1 of the first embodiment has a U shape, whereas the separation wall 51 has a “K” shape of Hiragana. ing. Although the square-shaped separation wall 51 is separated from the outer periphery of the polishing pad 12 by about 1/4 of the two locations in contact with the outer periphery of the polishing pad 12, the separation wall 51 is in a direction that is further away from the outer periphery of the polishing pad 12. Therefore, the interval between the holding jigs 23 becomes larger.

  When the rectangular separating wall 51 in plan view is divided into two at the bent portion, each corresponds to one of the U-shaped separating wall 21 of the polishing apparatus 1 cut so as to be plane-symmetric. That is, the separation wall 51 has a convex curve toward the upstream in the rotation direction of the polishing pad 12 in the non-polishing region 41, and also has a convex curve toward the upstream in the rotation direction of the polishing pad 12. ing. The bent portion of the rectangular separation wall 51 in plan view is located at the center of the polishing pad 12. Other configurations are the same as those of the polishing apparatus 1 of the first embodiment. Further, the polishing method is the same as that of the polishing apparatus 1 of the first embodiment.

  In the non-polishing region 41, the separation wall 51 has a downstream curvature opposite to the curvature of the first embodiment. As a result, the polishing apparatus 2 can place the top ring 25 close to the separation wall 51. Since the cooled polishing pad 12 reaches directly under the top ring 25 in a short time, there is an advantage that the cooling efficiency is improved. The separation wall 51 can be V-shaped. Although the position of the top ring 25 has to be somewhat separated from the square-shaped separation wall, the V-shaped separation wall has a shape that is easy to form.

  The polishing apparatus 2 has the same effects as the polishing apparatus 1 of the first embodiment.

(Third embodiment)
A polishing apparatus and a polishing method according to a third embodiment of the present invention will be described with reference to FIG. The difference from the polishing apparatus 1 of the first embodiment is that a plurality of cooling medium supply pipes are provided. In addition, the same code | symbol is attached | subjected to the same component as 1st Embodiment, and the description is abbreviate | omitted.

  As shown in FIG. 4, the polishing apparatus 3 is provided with a plurality of cooling medium supply pipes 55. Other configurations are the same as those of the polishing apparatus 1 of the first embodiment. The cooling medium supply pipe 55 is arranged so that the supply port covers the doughnut-shaped polishing contact surface 37 in the radial direction substantially linearly from the center of the polishing pad 12 in the non-polishing region 41 along the radius in the outer peripheral direction. Has been. Each cooling medium supply pipe 55 can independently control the temperature, flow rate, and position of the supply port of the cooling medium. In addition, it is possible to supply the cooling medium from six supply ports by arranging one cooling medium supply tube 55 having a plurality of supply ports, for example, three cooling medium supply tubes 55. . The supply port of the cooling medium supply pipe 55 may be a shower head. Further, the cooling medium supply pipe 55 is not limited to the linear arrangement in the radial direction of the cooling medium supply pipe 55, but is an arrangement in which the temperature distribution of the polishing pad 12 can be adjusted better. Can be done. Further, the separation wall 21 can be replaced with the separation wall 51 of the second embodiment.

  The polishing method by the polishing apparatus 3 is the same as the polishing apparatus 1 of the first embodiment, except that the cooling medium is supplied from a plurality of cooling medium supply pipes 55.

  The polishing apparatus 3 can make the temperature distribution of the polishing pad 12 into a desired shape by independently controlling the temperature, flow rate, and the like of the cooling medium of the plurality of cooling medium supply pipes 55. That is, the temperature distribution of the measurement line 45 shown in the first embodiment can be flattened as shown in FIG. This is achieved by lowering the temperature of the cooling medium at the center of the polishing contact surface 37 or increasing the flow rate of the cooling medium at the center of the plurality of cooling medium supply pipes 55.

  By performing the CMP process using the polishing apparatus 3 that realizes such a temperature distribution of the polishing pad 12, the semiconductor wafer 27 can make the characteristics of the semiconductor devices formed therein more uniform. It becomes.

  The polishing apparatus 3 has the same effects as the polishing apparatus 1 of the first embodiment.

  As mentioned above, this invention is not limited to the said Example, In the range which does not deviate from the summary of this invention, it can change and implement variously.

  For example, in the embodiment, the example in which the separation wall is in contact with the outer periphery of the polishing pad at two locations that are separated by about 1/4 of the outer periphery of the polishing pad is shown. It is possible to set. What is necessary is just to perform desired polishing pad cooling in the non-polishing area defined by the separation wall.

Furthermore, the structure as described in the following supplementary notes can be considered.
(Supplementary Note 1) A polishing pad is attached to the upper surface, a rotatable turntable, a holding means for rotatably holding a polishing object, and a polishing surface to be polished facing the polishing pad, and an upper surface of the polishing pad The polishing pad is partitioned into a polishing region in which the holding means disposed opposite to the polishing pad is disposed and a non-polishing region in which the holding means is not disposed, and the polishing pad in the non-polishing region A slurry is supplied to a separation wall continuously including a band of a doughnut-shaped polishing contact surface formed by contacting the holding means with the polishing pad rotating in a radial direction, and the upper surface of the polishing pad on the polishing region side A polishing apparatus comprising: a slurry supply pipe that performs cooling; and a cooling medium supply pipe that supplies a cooling medium to the upper surface of the polishing pad in the non-polishing region.

(Supplementary Note 2) The separation wall has a shape in which two curved curves that are convex upstream of the polishing pad in a plan view are connected to each other at a rotation angle portion of the polishing pad, separated by a certain angle. The polishing apparatus according to Appendix 1.

(Supplementary note 3) The polishing apparatus according to supplementary note 1, wherein at least a part of a surface of the separation wall is formed of one of PEEK, PPS, and fluororesin.

(Supplementary note 4) The polishing apparatus according to supplementary note 1, wherein the cooling medium supply pipe is movable in a radial direction of the polishing pad.

(Supplementary note 5) The polishing apparatus according to supplementary note 1, wherein the cooling medium supply pipe is capable of supplying a temperature-controlled cooling medium.

(Supplementary note 6) The polishing apparatus according to supplementary note 1, wherein the cooling medium is a gas.

(Supplementary note 7) The polishing apparatus according to supplementary note 1, wherein the cooling medium supply pipe is provided with a porous shower head at a supply port facing the upper surface of the polishing pad.

1, 2, 3 Polishing apparatus 11 Turntable 12 Polishing pad 15 Casing 16 Funnels 21, 51 Separation wall 23 Holding jig 25 Top ring 27 Semiconductor wafer 29 Retainer ring 31 Slurry supply pipe 33 Pure water supply pipe 35, 55 Cooling medium supply Tube 37 Polishing contact surface 41 Non-polishing region 43 Polishing region 45 Measuring line

Claims (5)

A polishing pad is affixed to the upper surface, and a rotatable turntable,
Holding means for rotatably holding an object to be polished and disposing the polishing surface of the object to be polished opposite the polishing pad;
The polishing pad is partitioned into a polishing region that is in contact with the upper surface of the polishing pad and is disposed opposite to the polishing pad, and a non-polishing region where the holding unit is not disposed. A separating wall continuously including a doughnut-shaped polishing contact surface band formed by contacting the holding means with the rotating polishing pad rotating in the radial direction of the polishing pad;
A slurry supply pipe for supplying slurry to the upper surface of the polishing pad on the polishing region side;
A cooling medium supply pipe for supplying a cooling medium to the upper surface of the polishing pad in the non-polishing region;
A polishing apparatus comprising:   2. The polishing apparatus according to claim 1, wherein the separation wall has a U shape in a plan view, and a bottom portion of the U shape is at a rotation center portion of the polishing pad.   3. The polishing apparatus according to claim 1, wherein a plurality of the cooling medium supply pipes are arranged along a radial direction of the polishing pad, and the cooling medium can be supplied independently controlled. 4. .   The polishing apparatus according to claim 1, wherein the cooling medium is pure water. The polishing pad that is attached to a turntable with a separation wall that partitions the polishing pad in a polishing region in which a holding means for polishing is disposed opposite to the polishing pad and a non-polishing region in which the holding means is not provided A step of contacting with,
Supplying a cooling medium for cooling the surface of the polishing pad to the non-polishing region of the rotating polishing pad;
Supplying slurry to the polishing region;
Pressing the rotating polishing object held by the holding means to the polishing area supplied with the slurry;
A polishing method comprising:

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