JP4412192B2 - Polishing pad dressing method - Google Patents

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. Further, the work (electronic device or the like) may be scratched due to agglomerated abrasives or detachment from the pad dresser.

  In addition, the polishing pad pores or grooves may be clogged with residues of polishing waste or slurry (abrasive), which may cause scratches on the workpiece.

  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.

  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 provides a polishing pad dressing method in a polishing apparatus for performing processing by bringing a workpiece into contact with a polishing pad while supplying slurry, and comprising two or more fluids including a cleaning liquid and a gas. There is provided a polishing pad dressing method characterized in that the polishing pad is dressed by mixing and ejecting from a nozzle toward the polishing pad, and the polishing pad is washed with a rinse liquid having a flow rate larger than that of the cleaning liquid. .

The present invention also relates to a polishing pad dressing method in a polishing apparatus for performing processing by bringing a workpiece into contact with a polishing pad while supplying slurry, and mixing two or more fluids including a cleaning liquid and a gas, and performing the polishing from a nozzle There is provided a polishing pad dressing method characterized in that a polishing pad is dressed by being ejected toward the pad, and then the polishing pad is washed with a rinse liquid having a larger flow rate than the cleaning liquid.

The present invention is also 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 directs the cleaning liquid applied with ultrasonic vibration from the nozzle toward the polishing pad. There is provided a polishing pad dressing method characterized in that the polishing pad is dressed by jetting and the polishing pad is washed with a rinse liquid having a larger flow rate than the cleaning liquid.

The present invention is also 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 directs the cleaning liquid applied with ultrasonic vibration from the nozzle toward the polishing pad. A polishing pad dressing method is provided, wherein dressing of the polishing pad is performed by jetting, and then the polishing pad is cleaned with a rinse liquid having a flow rate larger than that of the cleaning liquid.

According to the present invention, since the polishing pad is washed with a large flow of rinsing liquid 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 jetting the cleaning liquid, the polishing pad is The disadvantage of fouling does not occur and good dressing results are obtained.

  According to the present invention, in addition to the conventional dressing method using a pad dresser, two or more fluids including cleaning liquid and gas are mixed and ejected from the nozzle toward the polishing pad to perform dressing of the polishing pad. The removed polishing debris can be washed away immediately.

  Further, according to the present invention, in addition to the conventional dressing method using the pad dresser, the cleaning liquid applied with ultrasonic vibrations is ejected from the nozzle toward the polishing pad to perform dressing of the polishing pad. The abrasive debris can be washed away immediately.

  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. FIG. 3 illustrates the nozzle 14 and is a cross-sectional view of the nozzle 14. The nozzle 14 has a discharge port 22, and the compressed air supplied from the compressed air supply port 24 and the cleaning water supplied from the cleaning water supply port 26 are mixed therein to atomize from the discharge port 22. It is the structure of ejecting.

  Various patterns such as a circular pattern, an oval or oval pattern, and a rectangular pattern can be adopted as the spray pattern (spray pattern) ejected from the discharge port 22, and the type of the nozzle 14 according to this has various specifications. Things can be adopted.

  One end of a flexible pressure hose 15 that is a compressed air supply pipe is connected to the compressed air supply port 24 of the nozzle 14, and the other end of the flexible pressure resistant hose 15 is a compressed air supply source (for example, an air compressor) 15A. It is connected to the. The flexible pressure hose 15 is not shown in FIG.

  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 and sent to the nozzle 14, mixed with compressed air, 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, the nozzle 14 and the pad dresser 60 can be caused to swing in the left-right direction around the rotary stage 18 as a rotation center. 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 and the compressed air supply source 15 </ b> A are 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 mist and collides with the polishing pad 50.

  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 scraps are washed away with the cleaning liquid in the form of mist, it is not necessary to rub the polishing pad 50 strongly with the pad dresser 60.

  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 this dressing means, the flow rate of the cleaning liquid, 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. It has been sent. 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 achieve the above cleaning liquid flow rate, cleaning liquid mist size, and collision speed, set the cleaning liquid supply volume, cleaning liquid supply pressure, compressed air supply volume, and compressed air supply pressure to appropriate values. It is preferable to do.

  Therefore, when the supply pressure of the cleaning liquid to the nozzle 14 can be set to 0.5 MPa, for example, and the supply pressure of the compressed air to the nozzle 14 is set to 0.5 MPa, for example, the supply flow rate of the cleaning liquid is 3 liters / minute and the air flow rate Can achieve the above-mentioned particle diameter and particle speed with a nozzle 14 of 150 liters / minute.

  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. 4 is a plan view of an essential 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.

  This embodiment differs from the first embodiment in the configuration of the dressing means (the pad dresser 60 and the nozzle 114) and the configuration of the slurry supply arm 53.

  First, the nozzle 114 will be described. FIG. 5 is a cross-sectional view of the nozzle 114. The nozzle 114 includes a nozzle body 116 that is a cylindrical member having an inner diameter extending from the substantially central portion toward the rear (base end portion), and an inner tube that is inserted and fixed to the inner peripheral portion of the nozzle body 116 with a predetermined clearance. 118.

  The base end portions of the nozzle body 116 and the inner pipe 118 are a compressed air supply port 116A and a cleaning water supply port 118A, respectively, so that compressed air and cleaning water can be supplied. The supplied compressed air and washing water are mixed, atomized, and ejected at the tip of the inner pipe 118.

  Regarding the dressing means, in this embodiment, the pad dresser 60 is rotatably supported at the tip of the arm 42 as in the first embodiment, but the nozzle 114 is different from the first embodiment. It is fixed to the side of the arm 42. The cleaning liquid is supplied to the nozzle 114 through the supply pipe 14A from the pump 20 (see FIG. 1).

  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 114) 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.

The configuration of the above slurry supply arm 53, unlike the first embodiment, Li Nsu liquid can be supplied over a wide range up to the outer periphery from the center of the polishing pad 50.

  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. 4, 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 114 or after dressing by the nozzle 114, the rinsing liquid is supplied onto the polishing pad 50 from the rinsing liquid supply nozzles 55, 55. 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, the entire surface of the polishing pad 50 can be completely dressed 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 114. 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 114 is 1 liter / minute, the supply flow rate of the rinsing liquid is preferably 2 to 100 liter / minute, but it is optimally supplied depending on conditions such as the size of the polishing surface plate 52. The flow rate changes.

  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 114 toward the polishing pad 50 to perform dressing of the polishing pad 50, and a rinse liquid having a larger flow rate than the cleaning liquid is supplied from the rinse 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 sprayed from the nozzle 114 toward the polishing pad 50 to dress the polishing pad 50, and then a 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. 4 of the second embodiment. In addition, about the same and similar member as FIG.1, FIG2 and FIG.4, the same code | symbol is attached | subjected and the detailed description is abbreviate | omitted.

  This embodiment is different from the second embodiment in the configuration of the nozzle 214 of the dressing means (the type and fixing method of the nozzle 214). That is, the nozzle 214 is common to the second embodiment in that the nozzle 214 is arranged on the side surface of the arm 42, but the nozzle 214 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 214 is performed from the pump 20 (see FIG. 1) through the supply pipe 14A.

  FIG. 8 is a cross-sectional view illustrating the configuration of the nozzle 214. The nozzle 214 is a flowing water type ultrasonic cleaner, and includes a nozzle body 216, a cleaning water supply port 218 formed on a side surface of the nozzle body 216, and an ultrasonic vibrator provided at a rear end portion inside the nozzle body 216. 220, a drive circuit (not shown) for driving the ultrasonic transducer 220, and a discharge port 222 formed at the tip of the nozzle body 216.

  In the nozzle 214, the cleaning water supplied from the cleaning water supply port 218 is applied with ultrasonic vibration 224 by the ultrasonic vibrator 220, and in this state, is atomized and ejected from the discharge port 222.

  As the type of the nozzle 214, nozzles having various specifications can be adopted depending on the spray pattern, the effect of the ultrasonic vibration 224, and the like. For example, a full cone having a circular injection pattern, an ultrasonic frequency of 2 kHz, an output of 1 kW, and a flow rate of 1 liter / min can be used. Depending on the type of polishing pad 50, the type of slurry, etc. It is necessary to change the frequency and output.

  The operation of the third embodiment corresponding to the above configuration will be described. During 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 214 is moved. Dressing is performed.

  At this time, the nozzle 214 can be slid in the longitudinal direction while the position of the pad dresser 60 is fixed. Therefore, while the position of the pad dresser 60 is fixed, the cleaning liquid is ejected from the nozzle 214 toward the polishing pad 50 to perform dressing on substantially the entire surface of the polishing pad 50.

  As described above, according to the third embodiment of the dressing method of the polishing pad according to the present invention, in addition to the conventional dressing method using the pad dresser 60, the cleaning liquid to which the ultrasonic vibration 224 is applied is applied to the polishing pad 50 from the nozzle 214. Since the polishing pad 50 is dressed by being jetted out, the polishing scraps scraped by the pad dresser 60 can be immediately washed away. Further, since the polishing pad 50 is washed away with the cleaning liquid, it is not necessary to dress the polishing pad 50 with the pad dresser 60 more strongly than necessary.

  Furthermore, since the cleaning liquid applied with the ultrasonic vibration 224 collides with the polishing pad 50 and the cleaning liquid reaches the depth of the polishing pad 50 sufficiently, the pad dresser 60 hits the polishing pad 50 and pushes the polishing pad 50. The effect of washing can be produced. Therefore, the polishing debris accumulated in the deep layer of the polishing pad 50 can float on the surface layer of the polishing pad 50 and be removed.

  Next, another embodiment (fourth embodiment) of the polishing pad dressing method 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. 8 shows the first embodiment, FIG. 4 shows the second embodiment, and FIG. This corresponds to FIG. 6 of the embodiment. In addition, the same code | symbol is attached | subjected about the same and similar member as FIG.1, FIG.2, FIG.4 and FIG.6, 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 illustration of the flexible pressure-resistant hose 15 is omitted.

  In the dressing means, the nozzle 14 (see FIG. 3) is employed. Instead, the nozzle 114 (see FIG. 5) of the second embodiment or the nozzle 214 (see FIG. 7) of the third embodiment. May be used.

  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. 8 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. 9 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. 9 shows the first embodiment, FIG. 4 shows the second embodiment, and FIG. This corresponds to FIG. 6 of the embodiment and FIG. 8 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.4, FIG.6 and FIG.8, 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 (which may be the nozzle 114 or the nozzle 214) is disposed on the back surface of the pad dresser 60, and the cleaning liquid is directed toward the polishing pad 50 from the through hole provided in the pad dresser 60 or the inner and outer periphery of the pad dresser 60. It comes to be ejected. The supply of the cleaning liquid to the nozzle 14 (114, 214) is performed from the pump 20 (see FIG. 1) through the supply pipe 14A.

  Hereinafter, details of the pad dresser 60 will be described. 10 to 13 are plan views (bottom views) of the pad dresser 60. The pad dresser 60 shown in FIG. 10 has a disc shape, and has a configuration 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. 11 has a disc shape and is provided with a plurality of (eight in the drawing) 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. 12 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. 13 has an annular shape, and a ring-shaped member 63 is provided on the inner peripheral side thereof, and a plurality (four in the figure) of through-holes 63A, 63A,. More cleaning liquid is ejected.

  As described above, by adopting any one of the configurations shown in FIGS. 10 to 13, a synergistic effect obtained by combining two kinds of dressing methods such as the pad dresser 60 and the nozzles 14 (114, 214) can be obtained.

  That is, in any configuration, since the pad dresser 60 and the nozzle 14 (114, 214) are arranged adjacent to each other, foreign matters such as polishing scraps scraped from the polishing pad 50 by the pad dresser 60 The washing liquid ejected from the nozzles 14 (114, 214) can be immediately washed away.

  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 nozzle 14 (114) employs a configuration in which two fluids of cleaning liquid and compressed air are mixed, but three or more fluids (for example, one type of liquid and two types of gas) or more. It is also possible to adopt a configuration that mixes these fluids. In the present embodiment, a configuration in which cleaning liquid and compressed air are mixed inside or at the tip of the nozzle 14 (114) is adopted, but a configuration in which two or more fluids are mixed upstream of the nozzle. May be adopted.

  In the second embodiment of the present invention (see FIG. 4), six rinse liquid supply nozzles 55, 55... Are fixed to the lower surface of the slurry supply arm 53 at a predetermined interval. In place of the nozzles 55, 55..., A nozzle 214 (running water type ultrasonic cleaning machine) may be provided.

  Further, in the present embodiment, either a nozzle configured to mix two fluids (14 or 114) or a flowing water type ultrasonic cleaner (214) is employed as a nozzle of the dressing means. It can also be used together. Thus, if both are used together, better dressing can be performed.

  Further, 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 (for example, polyurethane pad) of the semiconductor wafer polishing apparatus is taken as an example of the dressing target, but 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 The principal part top view of the other polishing apparatus to which the dressing method of the polishing pad of this invention is applied Cross section of nozzle 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 Cross section of nozzle 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, 114, 214 ... Nozzle, 15 ... Flexible pressure hose, 16 ... Pipe, 20 ... Pump, 50 ... Polishing pad, 51 ... Wafer holding head, 52 ... Polishing surface plate, 53 ... Slurry supply arm, 60 ... Pad dresser, W ... Work

Claims (4)

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,
Two or more fluids including a cleaning liquid and a gas are mixed and ejected from a nozzle toward the polishing pad to perform dressing of the polishing pad, and the polishing pad is cleaned with a rinsing liquid having a larger flow rate than the cleaning liquid. A method of dressing a 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,
Two or more fluids including a cleaning liquid and a gas are mixed and ejected from the nozzle toward the polishing pad to dress 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. 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,
A polishing pad characterized in that a cleaning liquid to which ultrasonic vibration is applied is jetted from a nozzle toward the polishing pad to dress the polishing pad, and the polishing pad is cleaned with a rinse liquid having a larger flow rate than the cleaning liquid. Dressing method. 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,
Polishing liquid characterized in that cleaning liquid to which ultrasonic vibration is applied is sprayed from a nozzle toward the polishing pad to dress the polishing pad, and then the polishing pad is cleaned with a rinsing liquid having a larger flow rate than the cleaning liquid. Pad dressing method.

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