JP2006159317A - Dressing method of grinding pad - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dressing method of a grinding pad capable of dressing without damaging and polluting the grinding pad. <P>SOLUTION: This dressing method of the grinding pad on a grinding device 10 works by making a work W contact with the grinding pad 50 while supplying slurry. In this case, dressing of the grinding pad is carried out by pressurizing a pad dresser 60 on the grinding pad 50, making washing liquid into fog particles of 1μm-500μm in particle diameter and jetting the washing liquid particles toward the grinding pad from a nozzle 14 at a speed of 10m/sec-500m/sec. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polishing pad dressing method, and more particularly to a polishing pad dressing method that can be suitably applied to a polishing apparatus used in a planarization process of an interlayer film or the like of a semiconductor integrated circuit.

  Along with the reduction in the design rules of semiconductor integrated circuits, chemical mechanical polishing (CMP) has been frequently used in the planarization process of interlayer films and the like. The polishing of the wafer by CMP is performed by pressing the wafer against a rotating polishing pad with a predetermined pressure while rotating the wafer, and supplying abrasive slurry between the polishing pad and the wafer (see, for example, Patent Document 1). .)

Such a polishing pad needs to be dressed because clogging is caused by polishing debris such as reaction products and abrasive grains as it is used repeatedly. As dressing, a method of pressing a pad dresser made of a brush or a grindstone against the polishing pad to roughen the surface of the polishing pad is generally used.
JP 2001-54854 A

  However, the conventional dressing method cannot remove the polishing dust accumulated in the deep layer of the polishing pad. Further, since it is necessary to strongly rub the polishing pad with a brush or a grindstone, there is a disadvantage that the polishing pad is damaged or the polishing pad is contaminated with dust generated from the brush or the grindstone. In addition, scratches may be generated due to agglomerated abrasives or detachment from the pad dresser. Further, as the polishing pad is used, a residue of polishing agent or polishing debris may remain in the pores or grooves on the surface of the polishing pad, and scratches may occur.

  As described above, when a defect caused by the polishing pad occurs, the polishing pad needs to be replaced, which causes a large problem in manufacturing such as a reduction in operating rate, a reduction in yield, and an increase in material cost.

  In addition, as another dressing method of the polishing pad, a method of performing dressing by spraying high-pressure cleaning water on the polishing pad has been proposed, but polishing debris accumulated in the deep layer of the polishing pad by the high-pressure cleaning water is removed from the polishing pad. It has been pointed out that it is raised on the surface and contaminates the polishing pad.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a polishing pad dressing method capable of performing dressing without damaging or contaminating the polishing pad.

  In order to achieve the above object, the present invention according to claim 1 is a polishing pad dressing method in a polishing apparatus that performs processing by bringing a workpiece into contact with a polishing pad while supplying slurry, the pad being attached to the polishing pad. The dressing of the polishing pad is performed by pressing the dresser, and the cleaning liquid is sprayed from the nozzle toward the polishing pad at a speed of 10 m / second to 500 m / second in the form of a droplet having a droplet diameter of 1 μm to 500 μm. There is provided a polishing pad dressing method characterized by dressing a polishing pad.

  According to the present invention, in addition to the conventional dressing method using the pad dresser, the polishing liquid is jetted from the nozzle at a high speed to perform the dressing of the polishing pad, so that the polishing dust scraped out by the pad dresser can be immediately washed away. it can. Further, since the polishing pad is washed away with the cleaning liquid, it is not necessary to dress the polishing pad more strongly than necessary with a pad dresser. In addition, the size and impact speed of the cleaning liquid mist that collides with the polishing pad are optimized so that the cleaning liquid reaches the depth of the polishing pad sufficiently, so that the pad dresser hits the polishing pad and pushes the polishing pad. The effect of washing can be produced. Therefore, polishing debris accumulated in the deep layer of the polishing pad can be lifted to the surface layer of the polishing pad and removed.

  The present invention according to claim 2 provides the dressing method of the polishing pad according to claim 1, wherein the cleaning liquid is pressurized to 1 MPa to 50 MPa in order to eject the cleaning liquid from the nozzle. By pressurizing the cleaning liquid in this way, a good dressing effect by the cleaning liquid can be obtained.

  The present invention according to claim 3 provides the polishing pad dressing method according to claim 1 or 2, wherein the pad dresser is a plate-like body having a large number of diamond abrasive grains fixed on the surface thereof. Thus, a good dressing effect can be obtained by using a pad dresser made of a plate-like body having a large number of diamond abrasive grains fixed on the surface. Such a pad dresser can be formed by diamond electrodeposition or metal bond (resin bond or vitrified bond is also possible) diamond grindstone.

  According to a fourth aspect of the present invention, the polishing pad is dressed by the pad dresser simultaneously with the polishing process, and the polishing pad is dressed by ejecting the cleaning liquid after the polishing process. A method of dressing a polishing pad as described in 1. above. In this way, if dressing is performed in-situ with a pad dresser and dressing is performed by ejecting cleaning liquid in Ex-situ, downtime due to dressing can be minimized, and the operating rate is improved.

  The present invention according to claim 5 performs dressing of the polishing pad by the pad dresser simultaneously with polishing, and simultaneously performs dressing of the polishing pad by the pad dresser and dressing of the polishing pad by ejecting the cleaning liquid after polishing. The dressing method of the polishing pad of any one of Claims 1-3 is provided. As described above, even when dressing with the pad dresser is performed in-situ, and dressing with the pad dresser and ejection of the cleaning liquid are performed with Ex-situ, the downtime due to the dressing can be reduced, and the operating rate is improved.

  The present invention according to claim 6 is the polishing pad according to any one of claims 1 to 3, wherein dressing of the polishing pad by the pad dresser and dressing of the polishing pad by ejection of the cleaning liquid are simultaneously performed after polishing. Provide a dressing method. In-situ dressing is unsuitable in the planarization process of an interlayer film such as Cu, and good results can be obtained by simultaneously performing dressing with a pad dresser and extruding cleaning liquid at the same time in this way. Is obtained.

  According to a seventh aspect of the present invention, dressing of the polishing pad by the pad dresser is performed after polishing, and thereafter dressing of the polishing pad by the pad dresser and dressing of the polishing pad by jetting the cleaning liquid are performed simultaneously. The dressing method of the polishing pad of any one of -3 is provided. Good results can also be obtained by simultaneously performing dressing with a pad dresser in such an ex-situ, subsequent dressing with a pad dresser, and dressing with a jet of cleaning liquid.

  The present invention according to claim 8 provides the polishing pad dressing method according to any one of claims 1 to 7, wherein the pad dresser is provided with one or more through holes, and the cleaning liquid is ejected from the through holes. To do.

  The present invention according to claim 9 provides the polishing pad dressing method according to any one of claims 1 to 7, wherein the pad dresser is formed in a disk shape, and the cleaning liquid is ejected from an outer peripheral side of the pad dresser. .

  The present invention according to claim 10 provides the polishing pad dressing method according to any one of claims 1 to 7, wherein the pad dresser has an annular shape, and the cleaning liquid is ejected from an inner peripheral side of the pad dresser. To do.

  By adopting any one of the above configurations, a synergistic effect obtained by combining two kinds of dressing methods can be obtained.

  11. The polishing pad dressing method according to claim 1, wherein dressing of the polishing pad is performed while moving the pad dresser and the nozzle relative to the polishing pad. provide. By adopting such a configuration, the entire surface of the polishing pad can be uniformly dressed.

  The present invention according to claim 12 is a polishing pad dressing method in a polishing apparatus that performs processing by bringing a workpiece into contact with the polishing pad while supplying slurry, and the cleaning liquid is a mist having a droplet diameter of 1 μm or more and 500 μm or less. Dressing the polishing pad by spraying it from the nozzle toward the polishing pad at a speed of 10 m / second or more and 500 m / second or less, and cleaning the polishing pad with a rinse liquid having a flow rate larger than that of the cleaning liquid. A polishing pad dressing method is provided.

  According to a thirteenth aspect of the present invention, there is provided a polishing pad dressing method in a polishing apparatus that performs processing by bringing a workpiece into contact with a polishing pad while supplying slurry, and the cleaning liquid is a mist having a droplet diameter of 1 μm or more and 500 μm or less. The particles are sprayed from the nozzle toward the polishing pad at a speed of 10 m / second or more and 500 m / second or less to perform dressing of the polishing pad, and then the polishing pad is cleaned with a rinsing liquid having a larger flow rate than the cleaning liquid. A method for dressing a polishing pad is provided.

  In this way, even if polishing waste accumulated in the deep layer of the polishing pad floats on the surface of the polishing pad by performing dressing by spraying the cleaning liquid, the polishing pad is cleaned with a large flow of rinsing liquid, so the polishing pad is contaminated. Does not occur, and good dressing results can be obtained.

  The present invention according to claim 14 provides the polishing pad dressing method according to claim 12 or 13, wherein the cleaning liquid is pressurized to 1 MPa or more and 50 MPa or less in order to eject the cleaning liquid from the nozzle. By pressurizing the cleaning liquid in this way, a good dressing effect by the cleaning liquid can be obtained.

  According to the present invention, in addition to the conventional dressing method using the pad dresser, the polishing liquid is jetted from the nozzle at a high speed to perform the dressing of the polishing pad, so that the polishing dust scraped out by the pad dresser can be immediately washed away. it can.

  In addition, according to the present invention, even if the polishing waste accumulated in the deep layer of the polishing pad floats on the surface of the polishing pad by performing dressing by jetting the cleaning liquid, the polishing pad is cleaned with a large flow of rinsing liquid. The disadvantage of contaminating the polishing pad does not occur and good dressing results are obtained.

  A preferred embodiment (first embodiment) of a dressing method for a polishing pad according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a front view of a polishing apparatus 10 to which a dressing method for a polishing pad according to the present invention is applied, and FIG.

  As shown in FIGS. 1 and 2, the polishing apparatus 10 mainly includes a polishing platen 52, a wafer holding head 51 for holding a workpiece W, and a slurry (a solution in which an abrasive is dispersed. And a slurry supply arm 53 for supplying a chemical abrasive).

  The polishing surface plate 52 is formed in a disk shape, and a rotating shaft 54 is connected to the center of the lower surface thereof. The polishing surface plate 52 is rotated in the direction of the arrow in the figure by driving a motor 56 connected to the rotating shaft 54. A polishing pad 50 is attached to the upper surface of the polishing surface plate 52, and slurry is supplied onto the polishing pad 50 from a nozzle 53A at the tip of the slurry supply arm 53.

  The wafer holding head 51 is a disk-like member that holds the workpiece W on the lower surface, and a pressing force is transmitted from a pressing means (not shown) by a pressing shaft 51A connected to the center of the upper surface. As the polishing platen 52 rotates, it rotates (rotates) in the direction of the arrow in the figure.

  Next, the dressing means for the polishing pad, which is a feature of the present invention, will be described. The dressing means for the polishing pad includes a pad dresser 60 and a nozzle 14. These are supported by the pump 20 via the arm 42 and the pipe 16.

  Among these, the pad dresser 60 is a disk-shaped body having diamond abrasive grains fixed on the surface (lower surface). The pad dresser 60 is rotatably supported by the arm 42 via a shaft 60A connected to the center of the upper surface. Therefore, when the polishing surface plate 52 is rotationally driven in a state where the pad dresser 60 is pressed against the polishing pad 50, the pad dresser 60 also rotates (rotates).

  The nozzle 14 is arranged at a predetermined distance from the surface of the polishing pad 50. 3 and 4 illustrate the nozzle 14, FIG. 3 is a sectional view of the nozzle 14, and FIG. 4 is a bottom view of the nozzle 14. The nozzle 14 includes a nozzle chip 24 having a discharge port 22 and a nozzle case 26 in which the nozzle chip 24 is inserted. As shown in FIG. 4, the discharge port 22 is vertically long and is formed in an elliptical shape with a central portion expanding toward the front (lower side in FIG. 3). Various types of nozzles 14 can be used depending on the spray pattern.

  The nozzle 14 is connected to a pump 20 via a pipe 16, and the pump 20 is connected to a tank 24 via a flexible hose 22. The cleaning liquid stored in the tank 24 is pressurized by the pump 20, sent to the nozzle 14, and sprayed toward the polishing pad 50. The pipe 16 is engaged with the spindle of the motor 30 via a fan-shaped rack 26 and a pinion gear 28. The pump 20 is installed on the table 32 via the rotary stage 18.

  Therefore, by rotating the motor 30 forward or backward, it is possible to cause the nozzle 14 and the pad dresser 60 to swing in the left-right direction around the rotary stage 18. The swinging motion of the nozzle 14 and the pad dresser 60 is controlled via the motor 30 by a control unit (not shown). FIG. 2 shows this swinging motion, and the nozzle 14 and the pad dresser 60 can swing as indicated by arrows d and e.

  The pump 20 and the motor 30 are installed on a table 32. The table 32 is movable in the direction of arrow a on a rail 36 provided on a base 34, and an end of the table 32 is connected to an air cylinder 38 supported by the base 34 via a rod 40. It is connected. Therefore, by operating the air cylinder 38, the nozzle 14 and the pad dresser 60 can be moved in the arrow a direction via the table 32 or the like.

  The movement direction of the table 32 may be changed by changing the arrangement of the rail 36, the air cylinder 38, etc., and the nozzle 14 and the pad dresser 60 may be moved horizontally in a direction perpendicular to the axis of the pipe 16.

  As the cleaning liquid sprayed from the nozzle 14, water (ultra pure water, primary pure water, tap water, etc.) is generally used, but those obtained by adding chemicals to these can also be used.

  Next, the operation of the dressing means (pad dresser 60 and nozzle 14) for the polishing pad configured as described above will be described. When a polishing operation is performed with the polishing pad 50 and dressing of the polishing pad 50 is required, the table moving mechanism (air cylinder 38 or the like) is operated so that the nozzle 14 and the pad dresser 60 are positioned substantially on the center of the polishing pad 50. Then, the table 32 is moved. Then, the pad dresser 60 is pressed onto the polishing pad 50, and the pump 24 is operated to inject the cleaning liquid from the nozzle 14.

  The pad dresser 60 scrapes polishing debris accumulated on the polishing pad 50 in the outer circumferential direction of the polishing pad 50. The cleaning liquid sprayed from the nozzle 14 becomes a mist having a particle size of 1 μm or more and 500 μm or less, and collides with the polishing pad 50 at a speed of 10 m / s or more and 500 m / s or less.

  The cleaning liquid immediately rinses away the polishing scrapes scraped by the pad dresser 60 in the outer peripheral direction of the polishing pad 50. Since the scraped polishing debris is washed away with a high-pressure cleaning liquid, it is not necessary to rub the polishing pad 50 with the pad dresser 60 strongly.

  Therefore, it is possible to prevent the polishing pad 50 from being damaged, and further, it is possible to prevent dust from being generated due to wear of the pad dresser 60 to prevent the polishing pad 50 from being contaminated. It is possible to prevent the occurrence of scratches.

  In the present dressing means, the size of the mist of the cleaning liquid and the collision speed are optimized so that the cleaning liquid reaches the depth of the polishing pad 50 sufficiently, so that the clean cleaning liquid is always sent to the polishing pad 50. . Therefore, by rotating (swinging) the pad dresser 60 and pressing the polishing pad 50 with the pad dresser 60, an effect of washing the polishing pad 50 is produced. Thereby, the polishing debris accumulated in the deep layer of the polishing pad 50 can be lifted to the surface layer of the polishing pad 50 and removed.

  Then, the polishing pad 50 (polishing surface plate 52) is rotated in the direction of the arrow in FIG. 2 while rotating the pad dresser 60 and spraying the cleaning liquid from the nozzle 14 as described above. Further, by dressing the arm 42 while swinging it in the directions of arrows d and e in FIG. 2, the entire surface of the polishing pad 50 is completely dressed while sweeping the polishing debris on the polishing pad 50 toward the outer periphery of the polishing pad 50. The

  The particle size of the mist of the cleaning liquid that collides with the polishing pad 50 is preferably 1 μm to 500 μm, more preferably 1 μm to 300 μm, and still more preferably 1 μm to 100 μm.

  Too small mist easily loses kinetic energy due to air resistance or collision with the polishing pad 50, and too large mist cannot enter the hole of the polishing pad 50, so that all reach the depth of the polishing pad 50. Because you can't.

  The speed at which the mist of the cleaning liquid collides with the polishing pad 50 is preferably 10 m / s or more and 500 m / s or less, and more preferably 30 m / s or more and 150 m / s or less. This is because if the collision speed of the mist is too low, the kinetic energy is insufficient to reach the deep layer of the polishing pad 50, and if the collision speed of the mist is too high, the polishing pad 50 may be damaged.

  In order to realize the above-described mist size and collision speed of the cleaning liquid, when the discharge port of the nozzle 14 has an elliptical shape with a minor axis of 400 μm and a major axis of 600 μm, the cleaning liquid is supplied to the nozzle 14 at a pressure of 1 MPa to 50 MPa. It is preferable to supply at a pressure of 10 MPa to 30 MPa.

  In the operation of the dressing means for the polishing pad described above, the polishing process and the dressing are performed in accordance with the material of the workpiece (work W, pattern on the wafer, etc.), the type of the polishing pad 50, the composition of the abrasive slurry, and the like. Various variations are possible for the combination. Hereinafter, this variation will be described.

  1) A method in which the polishing pad 50 is dressed by the pad dresser 60 simultaneously with the polishing process, and the polishing pad 50 is dressed by ejecting a cleaning liquid from the nozzle 14 after the polishing process.

  As described above, if the dressing is performed by the pad dresser 60 in-situ and the dressing is performed by ejecting the cleaning liquid by Ex-situ, the downtime due to the dressing can be minimized, and the operating rate is improved.

  This dressing does not have to be performed for each processing of each workpiece W (wafer). For example, the dressing may be performed once for every 10 cassette processing (250 sheets) of the workpiece W (the following variations (variation 2)). The same applies to -6)).

  2) The polishing pad 50 is dressed by the pad dresser 60 simultaneously with the polishing process, and at the same time as the polishing pad 50 is dressed by the pad dresser 60 after the polishing process, the cleaning liquid is ejected from the nozzle 14 to dress the polishing pad 50. How to do.

  As described above, even if dressing by the pad dresser 60 is performed in-situ and dressing by the pad dresser 60 and dressing by jetting the cleaning liquid are performed in ex-situ, the downtime due to dressing can be reduced, and the operating rate is improved. .

  3) A method of performing dressing of the polishing pad 50 by ejecting a cleaning liquid from the nozzle 14 simultaneously with dressing of the polishing pad 50 by the pad dresser 60 after polishing.

  In-situ dressing is unsuitable in the planarization process of an interlayer film such as Cu, and it is preferable to perform dressing by the pad dresser 60 in ex-situ and dressing by jetting a cleaning solution at the same time. Results are obtained.

  4) A method of performing dressing of the polishing pad 50 by the pad dresser 60 after polishing and then dressing the polishing pad 50 by ejecting a cleaning liquid from the nozzle 14 simultaneously with dressing of the polishing pad 50 by the pad dresser 60.

  A good result can also be obtained by performing dressing by the pad dresser 60 in such an ex-situ, and subsequent dressing by the pad dresser 60 and dressing by spraying a cleaning liquid.

  Next, another embodiment (second embodiment) of the dressing method for a polishing pad according to the present invention will be described in detail. FIG. 5 is a plan view of a main part of another polishing apparatus to which the dressing method for a polishing pad of the present invention is applied, and corresponds to FIG. 2 of the first embodiment. In addition, about the member similar to FIG.1 and FIG.2, the same code | symbol is attached | subjected and the detailed description is abbreviate | omitted.

  The present embodiment is different from the first embodiment in the configuration of the dressing means (pad dresser 60 and nozzle 14) and the configuration of the slurry supply arm 53.

  Regarding the dressing means, in this embodiment, the pad dresser 60 is rotatably supported at the tip portion of the arm 42 as in the first embodiment, but the nozzle 14 is different from the first embodiment. It is fixed to the side of the arm 42. The cleaning liquid is supplied to the nozzle 14 from a pump 20 (see FIG. 1) through a supply pipe 14A.

  Note that, unlike the first embodiment, the arm 42 is configured to be performed by a rotation means (not shown) around the rotation center 42A (the same applies to the third to fifth embodiments below). .

  Although the configuration of the dressing means described above is different from that of the first embodiment, this basic operation is substantially the same as that of the first embodiment. The operation of the dressing means (pad dresser 60 and nozzle 14) for the polishing pad configured as described above is substantially the same as that of the first embodiment, and thus description thereof is omitted.

  In the case of not using the pad dresser 60 as in other variations (variations 5) and 6)) of the combination of polishing and dressing described later, the pad dresser 60 can be retracted upward. Yes.

  On the other hand, the slurry supply nozzle 53A is fixed to the tip of the slurry supply arm 53 as in the first embodiment. In this embodiment, in addition to this, six rinse liquid supply nozzles are provided. 55, 55... Are fixed to the lower surface of the slurry supply arm 53 at a predetermined interval.

  With the configuration of the slurry supply arm 53 described above, unlike the first embodiment, the rinse liquid can be supplied over a wide range from the center on the polishing pad 50 to the outer periphery.

  The operation of the slurry supply arm 53 configured as described above will be described. At the time of polishing, the slurry supply arm 53 is fixed at the position shown in FIG. 5, and the slurry is supplied onto the polishing pad 50 from the slurry supply nozzle 53A at the tip. At this time, no rinse liquid is supplied from the rinse liquid supply nozzles 55, 55.

  On the other hand, at the time of dressing by the nozzle 14 or after dressing by the nozzle 14, the rinsing liquid is supplied from the rinsing liquid supply nozzles 55, 55... Onto the polishing pad 50, and from the deep layer of the polishing pad 50 by the nozzle 14. The polishing debris that has floated to the surface layer of 50 is poured away in the outer circumferential direction of the polishing pad 50, and the entire surface of the polishing pad 50 is dressed without omission.

  At this time, since the polishing pad 50 (polishing surface plate 52) is rotating, even if the slurry supply arm 53 is fixed at the position shown in FIG. During dressing, no slurry is supplied onto the polishing pad 50 from the slurry supply nozzle 53A.

  As the rinsing liquid supplied from the rinsing liquid supply nozzles 55, 55..., Water (ultra-pure water, primary pure water, tap water, etc.) is generally used, but those added with chemicals can also be used. The supply flow rate of the rinse liquid is required to be larger than the flow rate of the cleaning liquid ejected from the nozzle 14. Thus, by increasing the supply flow rate of the rinsing liquid above the flow rate of the cleaning liquid, it is possible to flow away the polishing debris floating on the surface layer of the polishing pad 50 in the outer peripheral direction of the polishing pad 50.

  For example, when the flow rate of the cleaning liquid sprayed from the nozzle 14 is 1 liter / minute, the supply flow rate of the rinsing liquid is preferably 1 to 1000 liter / minute, and more preferably 10 to 100 liter / minute. The optimum flow rate of the cleaning liquid varies depending on the diameter of the polishing pad 50 and the number of nozzles 14. The rinsing liquid supplied from the rinsing liquid supply nozzles 55, 55... May be ejected simultaneously or sequentially.

  Next, variations of the combination of polishing and dressing according to the configuration of the second embodiment will be described.

  5) After polishing, the cleaning liquid is sprayed from the nozzle 14 toward the polishing pad 50 to dress the polishing pad 50, and a rinsing liquid having a larger flow rate than the cleaning liquid is supplied from the rinsing liquid supply nozzles 55, 55. The polishing pad 50 is cleaned by supplying it onto the substrate 50.

  As described above, even if polishing waste accumulated in the deep layer of the polishing pad 50 is raised on the surface of the polishing pad 50 by performing dressing by jetting the cleaning liquid, the polishing pad 50 is cleaned with a large amount of rinse liquid. The disadvantage of contaminating the pad 50 does not occur and good dressing results are obtained.

  6) After the polishing process, the cleaning liquid is ejected from the nozzle 14 toward the polishing pad 50 to dress the polishing pad 50. After that, the rinse liquid having a larger flow rate than the cleaning liquid is polished from the rinse liquid supply nozzles 55, 55. The polishing pad 50 is cleaned by supplying it onto the pad 50.

  As described above, even if polishing waste accumulated in the deep layer of the polishing pad 50 is raised on the surface of the polishing pad 50 by performing dressing by jetting the cleaning liquid, the polishing pad 50 is cleaned with a large amount of rinse liquid. The disadvantage of contaminating the pad 50 does not occur and good dressing results are obtained.

  Next, another embodiment (third embodiment) of the polishing pad dressing method according to the present invention will be described in detail. FIG. 6 is a plan view of an essential part of still another polishing apparatus to which the dressing method for a polishing pad of the present invention is applied, and corresponds to FIG. 2 of the first embodiment and FIG. 5 of the second embodiment. In addition, about the same and similar member as FIG.1, FIG.2 and FIG.5, the same code | symbol is attached | subjected and the detailed description is abbreviate | omitted.

  In this embodiment, what is different from the second embodiment is the configuration of the nozzle 14 of the dressing means. That is, the nozzle 14 is arranged on the side surface of the arm 42 in common with the second embodiment, but the nozzle 14 is slidable in the longitudinal direction with respect to the arm 42 via the nozzle guide 14B. It is supported by. The supply of the cleaning liquid to the nozzle 14 is performed from the pump 20 (see FIG. 1) through the supply pipe 14A.

  The operation of the third embodiment corresponding to the above configuration will be described. At the time of dressing by the dressing means, the arm 42 moves from the retracted position shown in FIG. 6 to the position of the imaginary line (two-dot chain line), and the polishing pad 50 of the pad dresser 60 and / or the nozzle 14 is moved. Dressing is performed.

  At this time, the nozzle 14 can be slid in the longitudinal direction with the position of the pad dresser 60 fixed. Accordingly, the cleaning liquid is ejected from the nozzle 14 toward the polishing pad 50 while the position of the pad dresser 60 is fixed, so that dressing of the entire surface of the polishing pad 50 can be performed.

  Next, another embodiment (fourth embodiment) of the polishing pad dressing method according to the present invention will be described in detail. FIG. 7 is a plan view of an essential part of still another polishing apparatus to which the dressing method for a polishing pad of the present invention is applied. FIG. 7 shows the first embodiment, FIG. 5 shows the second embodiment, and FIG. This corresponds to FIG. 6 of the embodiment. In addition, about the same and similar member as FIG.1, FIG.2, FIG.5 and FIG.6, the same code | symbol is attached | subjected and the detailed description is abbreviate | omitted.

  The present embodiment is different from the first embodiment in the configuration of the nozzle 14 of the dressing means. That is, the nozzle 14 is not disposed on the arm 42 but is disposed near the tip of the slurry supply arm 53 (inside the slurry supply nozzle 53A). The supply of the cleaning liquid to the nozzle 14 is performed from the pump 20 (see FIG. 1) through the supply pipe 14A.

  The operation of the fourth embodiment corresponding to the above configuration will be described. At the time of dressing by the dressing means, the arm 42 moves from the retracted position shown in FIG. 7 to the position of the imaginary line (two-dot chain line), and dressing of the polishing pad 50 by the pad dresser 60 is performed.

  At the same time as the dressing of the polishing pad 50 by the pad dresser 60, when the polishing pad 50 is dressed by spraying the cleaning liquid from the nozzle 14 toward the polishing pad 50, the position of the pad dresser 60 (the position of the arm 42) is fixed. In this state, the slurry supply arm 53 is swung, so that the cleaning liquid is jetted from the nozzle 14 toward the polishing pad 50 to perform dressing on the substantially entire surface of the polishing pad 50.

  Next, another embodiment (fifth embodiment) of the dressing method for a polishing pad according to the present invention will be described in detail. FIG. 8 is a plan view of an essential part of still another polishing apparatus to which the dressing method for a polishing pad according to the present invention is applied. FIG. 2 shows the first embodiment, FIG. 5 shows the second embodiment, and FIG. This corresponds to FIG. 6 of the embodiment and FIG. 7 of the fourth embodiment. In addition, the same code | symbol is attached | subjected about the same and similar member as FIG.1, FIG.2, FIG.5, FIG.6 and FIG.7, and the detailed description is abbreviate | omitted.

  The present embodiment differs from the first embodiment in the configuration of the pad dresser 60 of the dressing means and the configuration of the nozzle 14. That is, the nozzle 14 is disposed on the back surface of the pad dresser 60, and the cleaning liquid is ejected toward the polishing pad 50 from a through hole provided in the pad dresser 60 or from the inner and outer periphery of the pad dresser 60. The supply of the cleaning liquid to the nozzle 14 is performed from the pump 20 (see FIG. 1) through the supply pipe 14A.

  Hereinafter, details of the pad dresser 60 will be described. 9 to 12 are plan views (bottom views) of the pad dresser 60. FIG. The pad dresser 60 shown in FIG. 9 has a disk shape, and has a structure in which a through hole 60A is provided at the center, and a cleaning liquid is ejected from the through hole 60A.

  The pad dresser 60 shown in FIG. 10 has a disc shape and is provided with a plurality (eight in the figure) of through holes 60B, 60B,..., And a cleaning liquid is ejected from the through holes 60B, 60B,. It is a thing of composition.

  The pad dresser 60 shown in FIG. 11 has a disk shape, and a ring-shaped member 61 is provided on the outer peripheral side thereof, and a plurality of (four in the figure) through-holes 61A, 61A,. The cleaning liquid is ejected.

  The pad dresser 60 shown in FIG. 12 has an annular shape, and a ring-shaped member 63 is provided on the inner peripheral side. A plurality of (four in the figure) through-holes 63A, 63A,. More cleaning liquid is ejected.

  As described above, by adopting one of the configurations shown in FIGS. 9 to 12, a synergistic effect obtained by combining two kinds of dressing methods such as the pad dresser 60 and the nozzle 14 can be obtained.

  That is, in any configuration, since the pad dresser 60 and the nozzle 14 are disposed adjacent to each other, foreign matters such as polishing scraps scraped from the polishing pad 50 by the pad dresser 60 are ejected from the nozzle 14. Can be immediately washed away with a cleaning solution.

  As mentioned above, although each embodiment of the dressing method of the polishing pad which concerns on this invention was described, this invention is not limited to the said embodiment, Various aspects can be taken.

  For example, in the present embodiment, the wafer holding head 51 that holds the workpiece W on the lower surface is configured to rotate (rotate) in the direction of the arrow in each drawing according to the rotation of the polishing surface plate 52. The wafer holding head 51 can be provided with a unique driving means (motor or the like).

  Further, the polishing apparatus 10 shown in the present embodiment is of a type in which the workpiece W is held by the wafer holding head 51, but the present invention is arranged inside the ring-shaped member arranged on the polishing pad 50. The present invention can also be suitably applied to a polishing apparatus of a type in which the workpiece W is disposed in a carrier to be used, a so-called ring polisher.

  Furthermore, in the present embodiment, the polishing pad of a semiconductor wafer polishing apparatus (for example, a pad made of polyurethane) is taken as an example of the dressing target. However, the present invention is not limited to this, and other polishing apparatuses are used. It can also be suitably applied to dressings such as polishing buffs and porous grinding wheels.

Front view of a polishing apparatus to which a dressing method for a polishing pad of the present invention is applied FIG. 1 is a plan view of the main part of the polishing apparatus of FIG. Cross section of nozzle Nozzle bottom view The principal part top view of the other polishing apparatus to which the dressing method of the polishing pad of this invention is applied The principal part top view of the further another polishing apparatus to which the dressing method of the polishing pad of this invention is applied The principal part top view of the further another polishing apparatus to which the dressing method of the polishing pad of this invention is applied The principal part top view of the further another polishing apparatus to which the dressing method of the polishing pad of this invention is applied Top view of pad dresser Top view of pad dresser Top view of pad dresser Top view of pad dresser

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Polishing apparatus, 14 ... Nozzle, 16 ... Pipe, 20 ... Pump, 50 ... Polishing pad, 51 ... Wafer holding head, 52 ... Polishing surface plate, 53 ... Slurry supply arm, 60 ... Pad dresser, W ... Workpiece

Claims (14)

A polishing pad dressing method in a polishing apparatus that performs processing by bringing a workpiece into contact with a polishing pad while supplying slurry,
The polishing pad is dressed by pressing a pad dresser against the polishing pad, and the cleaning pad is sprayed from the nozzle at a speed of 10 m / second or more and 500 m / second or less with a cleaning liquid as a mist having a droplet diameter of 1 μm or more and 500 μm or less. A method for dressing a polishing pad, wherein the dressing of the polishing pad is performed by spraying toward the surface.   The polishing pad dressing method according to claim 1, wherein the cleaning liquid is pressurized to 1 MPa or more and 50 MPa or less in order to eject the cleaning liquid from the nozzle.   The polishing pad dressing method according to claim 1, wherein the pad dresser is a plate-like body having a large number of diamond abrasive grains fixed on the surface thereof.   The polishing pad dressing method according to any one of claims 1 to 3, wherein dressing of the polishing pad by the pad dresser is performed simultaneously with polishing processing, and dressing of the polishing pad by jetting of the cleaning liquid is performed after polishing processing.   The polishing pad is dressed by the pad dresser simultaneously with the polishing process, and the polishing pad dressing by the pad dresser and the polishing pad dressing by jetting the cleaning liquid are simultaneously performed after the polishing process. The polishing pad dressing method according to the item.   The polishing pad dressing method according to any one of claims 1 to 3, wherein dressing of the polishing pad by the pad dresser and dressing of the polishing pad by jetting the cleaning liquid are simultaneously performed after polishing.   The dressing of the polishing pad by the pad dresser is performed after the polishing process, and then the dressing of the polishing pad by the pad dresser and the dressing of the polishing pad by ejecting the cleaning liquid are simultaneously performed. Polishing pad dressing method.   The polishing pad dressing method according to claim 1, wherein the pad dresser is provided with one or more through holes, and the cleaning liquid is ejected from the through holes.   The dressing method for a polishing pad according to claim 1, wherein the pad dresser is formed in a disk shape, and the cleaning liquid is ejected from an outer peripheral side of the pad dresser.   The method for dressing a polishing pad according to claim 1, wherein the pad dresser is formed in an annular shape, and the cleaning liquid is ejected from an inner peripheral side of the pad dresser.   The dressing method of the polishing pad according to claim 1, wherein dressing of the polishing pad is performed while moving the pad dresser and the nozzle relative to the polishing pad. A polishing pad dressing method in a polishing apparatus that performs processing by bringing a workpiece into contact with a polishing pad while supplying slurry,
The cleaning liquid is sprayed from the nozzle toward the polishing pad at a speed of 10 m / second or more and 500 m / second or less in the form of a mist having a droplet diameter of 1 μm or more and 500 μm or less. A method of dressing a polishing pad, characterized in that the polishing pad is washed with a large amount of rinse liquid. A polishing pad dressing method in a polishing apparatus that performs processing by bringing a workpiece into contact with a polishing pad while supplying slurry,
The cleaning liquid is atomized with a droplet diameter of 1 μm or more and 500 μm or less and sprayed from the nozzle toward the polishing pad at a speed of 10 m / second or more and 500 m / second or less to dress the polishing pad. A polishing pad dressing method, wherein the polishing pad is washed with a rinse liquid of a large flow rate. The method of dressing a polishing pad according to claim 12 or 13, wherein the cleaning liquid is pressurized to 1 MPa or more and 50 MPa or less in order to eject the cleaning liquid from the nozzle.

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