JP3708740B2 - Polishing apparatus and polishing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a polishing apparatus and a polishing method having a mechanism for removing polishing debris.
[0002]
[Prior art]
In recent years, in the field of semiconductor device manufacturing, various fine processing techniques have been researched and developed along with the increase in density and miniaturization of semiconductor devices. Among them, the chemical mechanical polishing (CMP) technique has become an indispensable technique that is indispensable when performing planarization of interlayer insulating films, formation of plugs, formation of embedded metal wiring, isolation of embedded elements, and the like. .
[0003]
In the CMP process, polishing debris is generally generated during polishing. The polishing scrap includes polishing pad shavings, polishing target scraps, a reaction product of the polishing target film and slurry, and the like. These polishing scraps cause clogging of holes on the surface of the polishing pad that holds the abrasive grains, which causes a decrease in the polishing rate. In addition, the film to be polished may be scratched or the selectivity between the film to be polished and the stopper film may be lowered. Polishing debris that leads to such deterioration of the polishing characteristics should be removed from the polishing pad as needed. Ideally, this removal operation should be done at the same time, even during polishing. This is because polishing waste accumulates on the polishing pad as the polishing time increases.
[0004]
A method using a rotating brush is generally used as removal of polishing debris during polishing, that is, in-situ cleaning. However, this method has an effect of scraping off clogging of polishing dust, but has a small effect of positively removing the polishing dust from the polishing pad. This is because a part of the polishing debris is only removed from the polishing pad by centrifugal force together with the slurry waste liquid. Also, cleaning of the type that blows high-pressure water or high-pressure air onto the polishing pad has obstacles such as thinning the slurry dripped onto the polishing pad or removing it while it is still usable, and it should not be performed simultaneously with polishing. Have difficulty.
[0005]
[Problems to be solved by the invention]
As described above, polishing debris generated during polishing in the conventional CMP technique is a factor that degrades polishing characteristics, such as a decrease in polishing rate, scratch of the film to be polished, and a decrease in the selection ratio between the film to be polished and the stopper film. There have been proposed methods for removing abrasive debris using a rotating brush and methods for removing abrasive debris such as spraying high-pressure water or high-pressure air on the polishing pad, but the former has the effect of scavenging abrasive debris. However, the effect of positively removing polishing scraps is small, and the latter causes problems such as thinning of the slurry.
[0006]
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a polishing apparatus and a polishing method capable of effectively removing polishing debris that causes deterioration of polishing characteristics. is there.
[0007]
[Means for Solving the Problems]
A polishing apparatus according to claim 1 of the present invention has a polishing pad mounted on a main surface, and holds the polishing target such that a rotatable polishing surface plate and a surface to be polished face the polishing pad. a polished holding means, the disposed opposite to said polishing pad surface at a position different from the surface to be polished of the polishing target, the conjunction Fit rubbing a brush against the polishing pad, now the brush and onto the polishing platen surface a dresser for removing polishing debris of the polishing pad surface by rotating movement so as to pass through the off position is provided at a position away from the polishing table surface, comprising a cleaning mechanism for cleaning the brush Thus, the polishing of the object to be polished, the removal of polishing debris on the surface of the polishing pad, and the cleaning of the brush are performed simultaneously .
[0008]
Desirable embodiments of the present invention are shown below.
[0009]
(1) The cleaning mechanism includes a cleaning unit and a draining unit.
[0010]
(2) In (1), a partition plate is provided in each of the cleaning section and the draining section.
[0011]
(3) The cleaning mechanism is made of a chemical resin having chemical resistance.
[0012]
(4) As the cleaning water sprayed from the cleaning mechanism, water, an aqueous solution of acid or alkali, an aqueous solution of an oxidizing agent, or an aqueous solution of a surfactant is used.
[0013]
(5) The cleaning mechanism has an ultrasonic cleaning mechanism.
[0014]
(6) The polishing surface plate can be rotated.
[0015]
(7) The polishing object holding means is rotatable.
[0016]
(8) The object to be polished is a semiconductor wafer.
[0017]
Further, the polishing method according to claim 2 of the present invention relatively moves the polishing surface plate with the polishing pad attached on the main surface and the polishing object holding means disposed opposite to the polishing surface plate. The surface of the polishing object held by the polishing object holding means is polished, and the surface of the polishing pad is polished by rotating a brush attached to a dresser disposed opposite to the polishing pad against the polishing pad. A polishing method for removing debris , wherein the brush is passed through a position off the surface of the polishing platen, and the brush is washed at a position off the surface of the polishing platen, thereby polishing the object to be polished and the The polishing debris on the surface of the polishing pad is removed and the brush is simultaneously cleaned .
[0018]
Desirable embodiments of the present invention are shown below.
[0019]
(1) Polishing of a polishing target and removal of polishing debris on the surface of the polishing pad are simultaneously performed.
[0020]
(2) The object to be polished is a semiconductor wafer.
[0032]
(Function)
In the present invention, the brush attached to the dresser is disposed so as to pass through a position off the surface of the polishing surface plate, and a cleaning mechanism for cleaning the brush is provided at a position off the surface of the polishing surface plate. Therefore, when the polishing debris on the polishing pad surface is removed by the brush, the brush from which the polishing debris on the polishing pad surface has been removed rotates and comes off the surface of the polishing platen, and the brush is cleaned at that position. Accordingly, it is possible to completely remove the polishing dust generated during polishing outside the polishing pad. As a result, the polishing rate is stabilized, and scratches due to polishing dust are reduced. Further, since cleaning is performed at a position off the surface of the polishing platen, stable cleaning can be performed without diluting the slurry or removing slurry that can still be used. Further, by performing this cleaning simultaneously with the polishing of the object to be polished by the polishing pad, the manufacturing efficiency in the CMP process is improved.
[0033]
In another aspect of the present invention, a gas or cleaning water having a pressure for blowing off the polishing debris is sprayed from the nozzle toward the brush for removing the polishing debris. As a result, the polishing debris can be completely removed from the polishing pad, the polishing rate is stabilized, and scratches due to the polishing debris are reduced. Further, by performing this cleaning simultaneously with the polishing of the object to be polished by the polishing pad, the manufacturing efficiency in the CMP process is improved.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0035]
(First embodiment)
FIG. 1 is a diagram showing a configuration of a polishing apparatus according to a first embodiment of the present invention. FIG. 1 (a) is a cross-sectional view seen from the horizontal direction, and FIG. 1 (b) is a top view.
[0036]
As shown in FIG. 1 (a), the polishing surface plate 1 can be rotated in the direction of the arrow in the horizontal plane around the polishing surface plate rotating shaft 2, and the polishing pad 3 is disposed on the main surface thereof. It is affixed.
[0037]
Above the polishing platen 1, the semiconductor wafer holding means 4 and the dresser 5 are respectively arranged opposite to the polishing platen. The semiconductor wafer holding means 4 and the dresser 5 are disposed at positions where they do not interfere with each other. The former is the semiconductor wafer holding means rotating shaft 6 and the latter is centered on the dresser rotating shaft 7 and in the same direction as the polishing surface plate 1 in the horizontal plane. It can be rotated.
[0038]
The semiconductor wafer holding means rotating shaft 6 and the dresser rotating shaft 7 are in positions that do not overlap with the polishing surface plate rotating shaft 2 when viewed from above. The semiconductor wafer holding means 4 has a diameter smaller than the radius of the polishing surface plate 1, and holds the semiconductor wafer 8 to be polished on its lower surface by a vacuum chuck or the like. And the to-be-polished surface of the held semiconductor wafer 8 is pressed with a constant pressure by a driving mechanism such as a cylinder (not shown) so as to come into contact with the polishing surface of the polishing pad 3.
[0039]
The dresser 5 has a brush structure on the lower surface, and a brush 9 is formed in an annular shape on the surface. The bristles of the brush 9 are made of chemical fibers such as nylon and have a length of about 10 mm. The thickness of the hair and the flocking density may be those usually used. The brush 9 is pressed at a constant pressure by a driving mechanism such as a cylinder so as to come into contact with the polishing surface of the polishing pad 3. Then, polishing scraps are scraped out by rubbing the polishing surface of the polishing pad 3 while rotating around the dresser rotating shaft 7 as a central axis. The size and position of the dresser 5 are set so that the cleaning region on the polishing pad 3 by the brush 9 includes the locus region on the polishing pad 3 by the semiconductor wafer 8.
[0040]
The dresser rotating shaft 7 and the polishing surface plate rotating shaft are arranged at different positions. As shown in FIG. 1B, when the polishing apparatus is viewed from above, the dresser 5 is disposed so as to protrude from the polishing surface plate 1. Accordingly, the brush 9 formed on the dresser 5 is set so as to pass outside the polishing pad 3 when rotating about the dresser rotation shaft 7 as a central axis.
[0041]
Further, at a position where the dresser 5 protrudes from the polishing surface plate 1, a cleaning mechanism 10 is disposed below the protruding portion of the dresser 5. With this arrangement, the portion of the brush 9 that has rotated to reach the protruding position is cleaned by the cleaning mechanism 10. That is, the polishing debris adhering to the bristles of the brush 9 is removed by passing the cleaning mechanism 10 when the brush 9 comes to a position off the polishing pad 3. A slurry supply pipe 12 for supplying the slurry 11 onto the polishing pad 3 is provided above the polishing surface plate 1. The tip of the slurry supply pipe 12 is set near the rotating shaft 2 of the polishing surface plate 1. The slurry 11 is obtained by dispersing abrasive particles in water, and a chemical such as an oxidant may be added.
[0042]
Next, the detailed configuration of the cleaning mechanism 10 will be described with reference to the oblique view of FIG.
[0043]
The cleaning mechanism 10 has a box shape without a lid, and includes a cleaning unit 10a and a draining unit 10b. Both the cleaning part 10a and the draining part 10b are provided with a plurality of partition plates. In the cleaning unit 10a, cleaning water is supplied from the bottom through the pipe 13 and overflows. In this embodiment, water is used as the cleaning water. In the washing | cleaning part 10a, since the partition plate has not reached to the bottom, inflow and outflow of washing water are possible between adjacent containers via the partition plate. Since the bottom surface is not formed in the draining part 10b, the washing water does not accumulate.
[0044]
The cleaning mechanism 10 is preferably composed of a chemical resin having chemical resistance. For example, a partition plate having a thickness of about 1 mm is used, and adjacent partition plates may be arranged at intervals of about 10 mm. The number ratio of the partition plates in the cleaning unit 10a and the draining unit 10b may be about 2: 1, for example. The height of the cleaning mechanism 10 may be set so that the hair of the brush 9 hits the partition plate by about 5 mm from the tip. And it is desirable that this height can be adjusted.
[0045]
Next, the operation of the polishing apparatus according to the above embodiment will be described.
[0046]
First, as shown in FIG. 1 (a), the polishing surface plate 1 is rotated at a predetermined rotational speed in the direction indicated by the arrow with the polishing surface plate rotating shaft 2 as the central axis. Then, the slurry 11 is supplied via the slurry supply pipe 12 onto the polishing pad 3 that rotates as the polishing surface plate 1 rotates. Thereafter, the semiconductor wafer holding means 4 holding the semiconductor wafer 8 on the lower surface is lowered while rotating at a predetermined rotational speed in the direction indicated by the arrow with the semiconductor wafer holding means rotating shaft 6 as the central axis. Then, the surface to be polished of the semiconductor wafer 8 is brought into contact with the polishing surface of the polishing pad 3 by pressing with a predetermined pressure. In parallel with the rotation and lowering operation of the semiconductor wafer holding means 4, the dresser 5 is lowered while rotating at a predetermined rotational speed in the direction indicated by the arrow with the dresser rotation shaft 7 as the central axis. And it presses with a predetermined pressure so that the brush 9 may contact the polishing surface of the polishing pad 3.
[0047]
In this manner, the surface to be polished of the semiconductor wafer 8 is polished by being rubbed against the polishing surface of the polishing pad 3 with the slurry 11 interposed. Simultaneously with the polishing, the brush 9 of the dresser 5 removes polishing debris generated during the polishing.
[0048]
A specific operation for removing polishing dust will be described below.
[0049]
The bristles of the brush 9 to which the polishing scraps adhere are first cleaned in the cleaning section 10a while being immersed in cleaning water and being rubbed against the partition plate. Then, the hair of the brush 9 wet with the washing water is drained by rubbing against the partition plate of the draining portion 10b. By this mechanism, the polishing dust adhering to the bristles of the brush 9 is sufficiently removed. Further, since excess cleaning water is not brought onto the polishing pad 3, the slurry 11 is not diluted.
[0050]
The effect of the present invention by the cleaning operation using the cleaning mechanism 10 described above will be described.
[0051]
In a conventional rotating brush type polishing pad dresser, the entire brush exists inside the polishing pad during dressing. Therefore, although a part of the polishing scraps scraped by the brush is removed from the polishing pad by the centrifugal force together with the slurry waste liquid, most of the polishing scrap remains on the brush or the polishing pad. In addition, a type of dresser that blows off the polishing debris on the polishing pad with high-pressure water or high-pressure air has been devised, but it is used at the same time as polishing because the slurry is diluted or the slurry that is still usable is removed. It is inappropriate.
[0052]
On the other hand, by using the cleaning mechanism 10 shown in the present embodiment, it is possible to completely remove polishing debris generated during polishing out of the polishing pad, and the slurry can be thinned or still usable. It becomes possible to perform dressing of the polishing pad simultaneously with polishing without removing the film. Therefore, the polishing rate is stabilized, and scratches due to polishing dust are reduced. Such an improvement in polishing characteristics leads to an improvement in the reliability of a semiconductor device manufactured using CMP. Further, since polishing and dressing can be performed simultaneously, the manufacturing efficiency in the CMP process is improved.
[0053]
Next, FIG. 3 shows the polishing rate of the conventional cleaning brush type dresser and the brush cleaning of this embodiment. The horizontal axis is the wafer number, and the vertical axis is the polishing rate. The measurement conditions shown in FIG. 3 are as follows. That is, it represents a change with time of the average polishing rate over the entire surface of the wafer when CMP is performed on a tungsten blanket film formed on an 8-inch silicon wafer. The slurry was prepared by dispersing alumina in water by 3 wt% and adding iron nitrate by 8 wt%. As the polishing pad, PAN-W made by Rodel Nitta was used. The rotational speeds of the polishing surface plate, wafer holding means, and dresser are all 50 rpm, and the load during polishing is 300 gf / cm ² .
[0054]
When 24 wafers were polished continuously for 1 minute each, if a conventional dresser was used, the polishing rate gradually decreased and finally decreased by 400 Å / min compared to the beginning, but an improved dresser was used. When used, it can be seen that the polishing rate is substantially constant. Therefore, it can be seen that the variation within the lot is reduced.
[0055]
Next, FIG. 4 shows the change over time in the number of scratches in the tungsten film after CMP obtained in this experiment. The horizontal axis is the wafer number, and the vertical axis is the number of scratches. The number of scratches is relatively compared with the entire surface of each wafer. As shown in FIG. 4, when the conventional dresser is used, the number of scratches increases, and as the number of wafers increases, the number of scratches increases. However, when the improved dresser is used, the number of scratches increases. It can be seen that is almost constant at a low level. This suggests that, with the conventional dresser, the polishing debris is not completely removed but gradually accumulates, whereas with the improved dresser, the removal of the polishing debris is almost complete.
[0056]
The present invention is not limited to the above embodiment. In particular, the configuration of the cleaning mechanism 10 is an example for realizing the present invention, and it is not necessary to adopt the above configuration.
[0057]
A modification of the cleaning mechanism 10 shown in FIG. 2 is shown in FIG. The cleaning mechanism 50 shown in FIG. 5 is shown in a perspective view, and includes a cleaning unit 50a and a draining unit 50b as in the cleaning mechanism 10 shown in FIG. Hereinafter, detailed description of portions common to the cleaning mechanism 10 illustrated in FIG. 2 will be omitted.
[0058]
The cleaning unit 50a has a configuration in which the partition plate in the cleaning unit 10a illustrated in FIG. 2 is removed and the bottom surface is removed. A shower 53 is disposed at the bottom instead of the pipe 13, and cleaning water is sprayed upward. The hair of the brush 9 is washed by the shower 53. Further, the draining portion 50b is provided with a partition plate at a predetermined interval similarly to the draining portion 10b shown in FIG. By rubbing against the partition plate of the draining part 50b, the hair of the brush 9 containing the washing water is drained. A partition plate similar to the cleaning unit 10a shown in FIG. 2 may be provided above the shower 53 so that the hair of the brush 9 is sprayed on water and simultaneously rubbed against the partition plate for cleaning. .
[0059]
Further, in the cleaning mechanisms 10 and 50 shown in FIGS. 2 and 5, the partition plate can be replaced with a mesh-like one. Thus, the point is that the hair of the brush is cleaned at a position where the rotating brush is removed from the polishing pad, and various variations of the cleaning method can be considered. As washing water used for washing, an aqueous solution of acid or alkali, an aqueous solution of an oxidizing agent, or an aqueous solution of a surfactant can be used instead of water. Further, the cleaning mechanisms 10 and 50 can be provided with an ultrasonic cleaning function.
[0060]
Further, in the present embodiment, the case where the cleaning is performed simultaneously with the polishing of the semiconductor wafer by the polishing pad is shown, but it is not always necessary to perform the cleaning simultaneously, and even when the cleaning is performed between a plurality of times of polishing, There is an effect.
[0061]
(Second Embodiment)
6 and 7 are diagrams showing a configuration of a polishing apparatus according to a second embodiment of the present invention, in which FIG. 6 (a) is a cross-sectional view seen from the horizontal direction, FIG. 6 (b) is a top view, FIG. 7 (c) is a cross-sectional view seen from the direction of arrow c in FIG. 6 (b). The same components as those in FIG.
[0062]
The polishing surface plate 1 can rotate in the direction of the arrow in the horizontal plane around the polishing surface plate rotation axis 2, and a polishing pad 3 is attached to the upper surface thereof. Above the polishing surface plate 1, the semiconductor wafer holding means 4 and the dresser 65 are arranged at positions where they do not interfere with each other. The polishing surface plate is arranged in a horizontal plane around the semiconductor wafer holding means rotating shaft 6 and the dresser rotating shaft 67, respectively. 1 can be rotated in the same direction.
[0063]
The semiconductor wafer holding means rotating shaft 6 and the dresser rotating shaft 67 are in positions that do not overlap with the polishing surface plate rotating shaft 2 when viewed from above. The semiconductor wafer holding means 4 has a diameter smaller than the radius of the polishing surface plate 1, and holds the semiconductor wafer 8 on its lower surface by a vacuum chuck or the like. The held surface of the held semiconductor wafer 8 is pressed with a constant pressure by a driving mechanism such as a cylinder so that the polished surface of the semiconductor wafer 8 is in contact with the polishing surface of the polishing pad 3.
[0064]
The dresser 65 has a brush structure on the lower surface, and a brush 69 is formed in an annular shape on the surface. The bristles of the brush 69 are made of chemical fibers such as nylon and have a length of about 10 mm. The thickness of the hair and the density of flocking follow those usually used. The bristles of the brush 69 are pressed with a constant pressure by a driving mechanism such as a cylinder so that the bristles of the brush 69 are in contact with the polishing surface of the polishing pad 3. The size and position of the dresser 65 are set so that the cleaning region on the polishing pad 3 by the brush 69 includes the locus region on the polishing pad 3 by the semiconductor wafer 8.
[0065]
Also, a gas such as high-pressure air or a liquid such as high-pressure water can be sprayed onto the polishing pad 3 at the time of the brush 69 by the nozzle 71 shown in FIG. The pressure of the high-pressure air or high-pressure water sprayed from the nozzle 71 is preferably 10 kgf / cm ² or more, but is not necessarily limited to this condition, and even if it is 10 kgf / cm ² or less. Good.
[0066]
A slurry supply pipe 12 for supplying the slurry 11 onto the polishing pad 3 is provided above the polishing surface plate 1. The slurry 11 is obtained by dispersing abrasive particles in water, and a chemical such as an oxidant may be added.
[0067]
Next, the operation of the polishing apparatus according to this embodiment will be described.
[0068]
First, the polishing surface plate 1 is rotated through the polishing surface plate rotating shaft 2 at a predetermined number of rotations in the direction indicated by the arrow. Then, the slurry 11 is supplied onto the rotating polishing pad 3 through the slurry supply pipe 12. Thereafter, the semiconductor wafer holding means 4 holding the semiconductor wafer 8 on the lower surface is lowered while being rotated through the semiconductor wafer holding means rotating shaft 6 in the direction of the arrow in the drawing at a predetermined number of rotations. Then, the surface to be polished of the semiconductor wafer 8 is brought into contact with the polishing surface of the polishing pad 3 by pressing with a predetermined pressure. In parallel, the dresser 65 is lowered through the dresser rotating shaft 67 while rotating at a predetermined rotational speed in the direction indicated by the arrow in the drawing. Then, the brush 69 is pressed by a predetermined pressure so that the brush 69 contacts the polishing surface of the polishing pad 3.
[0069]
In this manner, the surface to be polished of the semiconductor wafer 8 is polished by being rubbed against the polishing surface of the polishing pad 3 with the slurry 11 interposed. Simultaneously with the polishing, the brush 69 of the dresser 65 removes polishing debris generated during the polishing.
[0070]
The brush 69 scrapes off polishing scraps by rubbing the polishing surface of the polishing pad 3 while rotating. In order to remove the scraped polishing waste together with the polishing waste liquid from the polishing pad, a gas such as high-pressure air or a liquid such as high-pressure water is passed through the nozzle 71 with respect to the polishing pad 3 at the portion of the brush 69. It sprays from the rotation back of the brush 69 along the tangential direction of the outermost periphery of the brush 69. FIG. By this spraying, the polishing waste liquid in which the polishing scraps carried by the brush 69 are mixed is stopped by the rotation of the brush 69 and forcibly removed from the polishing pad.
[0071]
The nozzle 71 needs to be positioned as much as possible outside the polishing pad 3 to reduce the influence on the concentration and amount of the slurry 11 on the polishing pad 3. Further, the nozzle 71 is constituted by a pipe made of chemical resin having a diameter of about 3/8 inch, and this pipe may be fixed to the casing 70 that houses the driving mechanism of the dresser 65.
[0072]
In the conventional rotary brush type dresser, the polishing scraps carried by the rotation of the brush are partly removed from the polishing pad together with the polishing waste liquid by centrifugal force. However, most of the polishing debris remained on the brush or polishing pad. Therefore, even if there is an effect of scraping clogged polishing debris on the polishing pad, the effect of positively removing the polishing debris is small. As in this embodiment, if a nozzle that blows off the polishing scraps together with the polishing waste liquid is provided, the polishing scraps are positively excluded from the polishing pad. In addition, since the position of the nozzle is outside the polishing pad and the nozzle is ejected toward the outside of the polishing pad, the influence on the concentration and amount of the slurry on the polishing pad can be reduced.
[0073]
Therefore, if this embodiment is used, it is possible to remove the polishing debris generated during the polishing out of the polishing pad only by making a simple improvement to the conventional polishing apparatus. It is possible to perform a dressing with less removal of possible slurry simultaneously with polishing. Therefore, the polishing rate is stabilized, and scratches due to polishing dust are reduced. Such an improvement in polishing characteristics leads to an improvement in the reliability of a semiconductor device manufactured using CMP. Further, since polishing and dressing can be performed simultaneously, the manufacturing efficiency in the CMP process is improved.
[0074]
In addition, the nozzle for blowing off or throwing away the polishing waste is not limited to this embodiment. The position and shape of the nozzle can be changed without departing from the spirit of the present embodiment. Further, in the present embodiment, the case where cleaning is performed simultaneously with the polishing of the semiconductor wafer by the polishing pad is shown, but it is not always necessary to perform the cleaning simultaneously. The effect of the invention is achieved.
[0075]
In the first and second embodiments, the semiconductor wafer polishing apparatus has been described. However, the polishing target is not limited to the semiconductor wafer. It can also be used when polishing with a grindstone instead of a polishing pad. In addition, the polishing surface plate and the semiconductor wafer holding means have been shown to be polished by rotating about their respective rotation axes, but the present invention is not limited to such a configuration, and the polishing surface plate and the semiconductor wafer holding means are relatively Anything can be used as long as it is moved and polished.
[0076]
【The invention's effect】
As described above in detail, according to the present invention, polishing debris generated during polishing can be completely removed from the polishing pad, so that the polishing characteristics are improved and the reliability of the object to be polished is improved.
[0077]
Further, by performing polishing and cleaning at the same time, the manufacturing efficiency in the polishing process is improved.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of a polishing apparatus according to a first embodiment of the present invention.
FIG. 2 is a perspective view showing a detailed configuration of a cleaning mechanism in the polishing apparatus according to the embodiment.
FIG. 3 is a view showing a polishing rate in the embodiment.
FIG. 4 is a view showing the number of scratches in the embodiment.
FIG. 5 is an oblique view showing in detail a modification of the cleaning mechanism in the polishing apparatus according to the embodiment.
FIG. 6 is a diagram showing an overall configuration of a polishing apparatus according to a second embodiment of the present invention.
FIG. 7 is a view showing an overall configuration of a polishing apparatus according to the embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Polishing surface plate 2 ... Polishing surface plate rotating shaft 3 ... Polishing pad 4 ... Semiconductor wafer holding means 5 ... Dresser 6 ... Semiconductor wafer holding means rotating shaft 7 ... Dresser rotating shaft 8 ... Semiconductor wafer 9 ... Brush 10, 50 ... Cleaning Mechanisms 10a, 50a ... cleaning units 10b, 50b ... draining unit 11 ... slurry 12 ... slurry supply pipe 13 ... pipe

Claims (2)

A polishing pad is mounted on the main surface, a rotatable polishing surface plate, a polishing object holding means for holding the polishing object so that a surface to be polished is opposed to the polishing pad, and a target to be polished The polishing pad is disposed opposite to the polishing surface at a position different from the polishing surface, and a brush is rubbed against the polishing pad, and the brush is rotated and moved so as to pass the position on the polishing surface plate and the position away from the polishing surface. A dresser that removes polishing debris on the surface of the polishing pad, and a cleaning mechanism that is provided at a position off the surface of the polishing surface plate and that cleans the brush,
A polishing apparatus characterized in that polishing of the object to be polished, removal of polishing debris on the surface of the polishing pad, and cleaning of the brush are simultaneously performed. The surface of the polishing object held by the polishing object holding means by relatively moving the polishing surface plate with the polishing pad mounted on the main surface and the polishing object holding means arranged opposite to the polishing surface plate A polishing method for removing polishing debris on the surface of the polishing pad by rotating a brush attached to a dresser disposed opposite to the polishing pad by rubbing against the polishing pad and rotating,
By passing the brush away from the surface of the polishing platen and cleaning the brush at a position off the surface of the polishing platen, polishing of the polishing object and removal of polishing debris on the surface of the polishing pad and A polishing method, wherein the brush is simultaneously cleaned.

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