JP2006332550A - Polishing pad dressing-property evaluation method and polishing pad dressing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polishing pad dressing-property evaluation which can perform a precise dressing-property evaluation and a polishing pad dressing method which reflects its evaluation result. <P>SOLUTION: It is the polishing pad dressing-property evaluation method when dressing the polishing pad in a polishing equipment 10 which carries out a polishing process, supplying slurry, and making the work in contact with the polishing pad 50. After adding a phosphor to the slurry and making a polishing process, the polishing pad is irradiated with ultraviolet rays, and the slurry remaining on the polishing pad is detected. Then the polishing pad dressing-property is evaluated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a polishing pad dressing evaluation method and a polishing pad dressing method, and more particularly to a polishing pad dressing evaluation 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. And a method for dressing a polishing pad.

  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.

  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.

  Further, the polishing pad is often subjected to a grid-like or concentric groove processing. This groove is generally formed with a depth of about 500 μm. Further, there may be a configuration in which a through hole is provided in the polishing pad for automatic end point detection of polishing and the through hole is closed with a transparent sheet.

  Thus, when a groove | channel or a through-hole is formed, the abrasive | polishing agent which aggregated in the bottom part (boundary with a transparent sheet) of a groove | channel or a through-hole is often difficult to remove by the conventional dressing method. That is, the diamond abrasive grains that protrude from the surface of the pad dresser often do not reach the abrasive aggregated at the bottom of the groove or through hole. And the abrasive | polishing agent which aggregated to the bottom part of this groove | channel or a through-hole falls, and a workpiece | work (electronic device etc.) may produce a scratch.

On the other hand, a dressing method using a high-pressure spray has been proposed by the present applicant (see, for example, Patent Document 2), and an excellent effect not found in conventional dressing methods has been confirmed. That is, according to this proposal, the polishing debris accumulated on the surface and the deep layer of the polishing pad can be removed regardless of the depth of the groove or the through hole, and a remarkable effect is obtained for preventing scratches.
JP 2001-54854 A Japanese Patent No. 2997804

  However, the conventional polishing pad dressing methods (including Patent Document 2) have no evaluation method for how much dressing has been made, and time management based on experience and polishing of products (including dummy workpieces) are performed. However, only the method of performing feedback by quality evaluation was adopted.

  In such a method, it is very difficult to perform the minimum dressing, and excessive dressing may result in a long downtime, resulting in a decrease in product quality (including a decrease in yield) due to insufficient dressing. There was a strong demand for improvement.

  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 evaluation method capable of performing accurate dressing evaluation and a polishing pad dressing method reflecting the evaluation result. And

  To achieve the above object, the present invention according to claim 1 is directed to dressing the polishing pad when dressing the polishing pad in a polishing apparatus that performs polishing by bringing a workpiece into contact with the polishing pad while supplying slurry. A method of evaluating the dressing of the polishing pad by adding a phosphor to the slurry and performing polishing, and then irradiating the polishing pad with ultraviolet rays to detect the slurry remaining on the polishing pad. A method for evaluating dressing properties of a polishing pad is provided.

  According to the first aspect of the present invention, the polishing pad is dressed by detecting the slurry remaining on the polishing pad by irradiating the polishing pad with ultraviolet rays after polishing by adding a phosphor to the slurry. Assess sex. Therefore, the dressing property of the polishing pad can be evaluated accurately and quantitatively, and as a result, the minimum necessary dressing can be realized.

  The present invention according to claim 2 is characterized in that the polishing pad is irradiated with the ultraviolet light after the slurry on the polishing pad is poured off after the polishing process is performed. Provide an evaluation method.

  According to the second aspect of the present invention, since the slurry on the polishing pad is poured off and then irradiated with ultraviolet rays, the abrasive that has agglomerated in the groove of the polishing pad, the bottom of the through hole (boundary with the transparent sheet), etc. Detection can be performed selectively, and detection accuracy can be improved.

  According to a third aspect of the present invention, there is provided the polishing pad dressing evaluation method according to the first or second aspect, wherein the phosphor is calcein or umbelliferone. According to the third aspect of the present invention, calcein or umbelliferone is adopted as the phosphor. These are inactive even when added to the slurry and can be detected in a small amount, which is preferable for the use of the present invention.

  The present invention according to claim 4 is a polishing pad dressing method for performing dressing of the polishing pad according to an evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3, wherein A polishing pad dressing method is characterized in that a cleaning liquid of 1 μm or more and 300 μm or less is ejected from a nozzle and collides with 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. To do.

  According to the fourth aspect of the present invention, since the dressing of the polishing pad is performed according to the evaluation result obtained by the dressing property evaluation method for the polishing pad, the necessary minimum dressing can be realized. Since the cleaning liquid having a particle size of 1 μm or more and 300 μm or less is ejected from the nozzle and collides with the polishing pad at a speed of 10 m / second or more and 500 m / second or less, the dressing is performed. Can be removed, and a remarkable effect can be obtained for the prevention of scratches.

  The present invention according to claim 5 is a polishing pad dressing method for performing dressing of the polishing pad according to an evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3, wherein The polishing pad is dressed by pressing a pad dresser against the pad, and the polishing pad is dressed by mixing two or more fluids including a cleaning liquid and gas and ejecting the fluid from a nozzle toward the polishing pad. A polishing pad dressing method is provided.

  According to the fifth aspect of the present invention, since the dressing of the polishing pad is performed according to the evaluation result of the dressing property evaluation method for the polishing pad, the minimum necessary dressing can be realized. Then, the dressing is performed by pressing the pad dresser against the polishing pad, and the dressing is performed by mixing two or more fluids including a cleaning liquid and a gas and ejecting from the nozzle. be able to. 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.

  Furthermore, since the size of the mist and the collision speed of the cleaning liquid that mixes two or more fluids including the cleaning liquid and gas and collide with the polishing pad are optimized, the cleaning liquid reaches the depth of the polishing pad sufficiently. The pad dresser can strike the polishing pad and push and wash the polishing pad. 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 6 is a polishing pad dressing method for performing dressing of the polishing pad according to the evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2, or 3, wherein the polishing pad A polishing pad that performs dressing of the polishing pad by pressing a pad dresser against the pad, and performs dressing of the polishing pad by spraying a cleaning liquid to which ultrasonic vibration is applied toward the polishing pad from a nozzle A dressing method is provided.

  According to the sixth aspect of the present invention, the dressing of the polishing pad is performed according to the evaluation result obtained by the above-described method for evaluating the dressing of the polishing pad, so that the minimum necessary dressing can be realized. Then, in addition to the conventional dressing method using a pad dresser, the cleaning liquid applied with ultrasonic vibrations is jetted from the nozzle toward the polishing pad to perform dressing of the polishing pad, so the polishing scrapes scraped by the pad dresser are immediately washed away. be able to. 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.

  Furthermore, since the cleaning liquid applied with ultrasonic vibration collides with the polishing pad so that the cleaning liquid reaches the depth of the polishing pad sufficiently, the pad dresser strikes the polishing pad and pushes the polishing pad. be able to. 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 7 is a polishing pad dressing method for performing dressing of the polishing pad according to the evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3, comprising: There is provided a dressing method for a polishing pad, characterized in that a dressing of the polishing pad is performed by pressing a pad dresser, which is a plate-like body on which a large number of diamond abrasive grains are fixed, against the polishing pad.

  According to the seventh aspect of the present invention, since the dressing of the polishing pad is performed according to the evaluation result by the dressing property evaluation method of the polishing pad, the necessary minimum dressing can be realized. And since the dressing is performed by pressing the pad dresser, which is a plate-like body having a large number of diamond abrasive grains fixed on the surface, against the polishing pad, a good dressing effect can be obtained. Such a pad dresser can be formed by diamond electrodeposition or metal bond (resin bond or vitrified bond is also possible) diamond grindstone.

  The present invention according to claim 8 is a polishing pad dressing method for performing dressing of the polishing pad according to an evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3, comprising a cleaning liquid and Two or more fluids containing 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 rinse liquid having a flow rate larger than that of the cleaning liquid. A method for dressing a polishing pad is provided.

  The present invention according to claim 9 is a polishing pad dressing method for performing dressing of the polishing pad according to the evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3, comprising a cleaning liquid and Two or more fluids including 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 rinse liquid having a flow rate larger than that of the cleaning liquid. A polishing pad dressing method is provided.

  The present invention according to claim 10 is a polishing pad dressing method for performing dressing of the polishing pad in accordance with an evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2, or 3, comprising ultrasonic waves The polishing pad is dressed by spraying a cleaning liquid to which vibration is applied toward the polishing pad from a nozzle, and the polishing pad is cleaned with a rinse liquid having a larger flow rate than the cleaning liquid. Provide a method.

  The present invention according to claim 11 is a polishing pad dressing method in which dressing of the polishing pad is performed according to the evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2, or 3, comprising ultrasonic waves A polishing liquid applied with vibration is sprayed from a nozzle toward the polishing pad to perform dressing of the polishing pad, and then the polishing pad is cleaned with a rinse liquid having a larger flow rate than the cleaning liquid. Provide a dressing method.

  According to the eighth to eleventh aspects of the present invention, since the dressing of the polishing pad is performed according to the evaluation result of the dressing property evaluation method for the polishing pad, the minimum necessary dressing can be realized. And 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, so that the polishing pad is contaminated. There are no drawbacks and good dressing results are obtained.

  The present invention according to claim 12 provides the polishing pad dressing method according to any one of claims 4 to 11, wherein dressing of the polishing pad is performed simultaneously with the polishing process.

  According to the twelfth aspect of the present invention, since the dressing of the polishing pad is performed simultaneously with the polishing process, the dressing performed after the polishing process can be shortened.

  According to the present invention, the dressing property of the polishing pad can be evaluated accurately and quantitatively. As a result, the minimum necessary dressing can be realized.

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

  As shown in FIG. 1, the polishing apparatus 10 mainly includes a polishing surface plate 52, and rotatably supports a polishing device body 10 </ b> A that rotates the polishing surface plate 52 and a wafer holding head 51 that holds a workpiece W. Polishing head 10B, slurry supply means (45, 47, 49) for supplying a slurry (a solution in which an abrasive is dispersed, and mechanochemical abrasive is used in many cases), and dressing of the polishing pad 50 It is comprised with the slurry detection means 25 etc. which evaluate property.

  In FIG. 1, a polishing pad dressing unit 90 to be described later is not shown.

  The polishing apparatus main body 10A is fixed on a friction table 10C, and the friction table 10C is fixed on a vibration isolation table 10D.

  The polishing surface plate 52 is formed in a disk shape, and is rotated in one direction by driving a motor (not shown) connected to the lower surface thereof. 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 the tip of the slurry pipe 47.

  The slurry supply means includes a slurry pipe 47, a peristaltic pump 45 provided in the middle of the slurry pipe 47, and a slurry tank 49 to which the base end of the slurry pipe 47 is connected.

  The wafer holding head 51 is a disk-like member that holds a workpiece W (not shown) on its lower surface, so that the pressing force is transmitted from the pressing means 10E in the direction of the arrow by the pressing shaft 51A connected to the center of the upper surface. It has become. Then, according to the rotation of the polishing surface plate 52, it rotates (rotates) in the same direction as the rotation of the polishing surface plate 52.

  Next, the slurry detection means 25 that is a characteristic part of the present invention will be described. The slurry detection unit 25 includes a UV (ultraviolet) lamp 27 and a camera system 29. These are supported by the upper ends of the support columns that are provided upright in the vicinity of the polishing apparatus main body 10A. The UV lamp 27 is set so as to be able to irradiate the surface of the polishing pad 50, and the camera system 29 is set so as to be able to photograph the surface of the polishing pad 50 irradiated with UV.

  That is, after polishing by adding phosphor to the slurry, the UV lamp 27 irradiates the polishing pad 50 with ultraviolet (UV) so that the slurry remaining on the polishing pad 50 can be detected by the camera system 29. It has become.

  As the UV lamp 27, various known ultraviolet irradiation means can be employed. As the camera system 29, various known imaging means can be employed, and in particular, a camera system using a CCD imaging device can be preferably employed.

  According to the slurry detection means 25 described above, the dressing property of the polishing pad 50 can be accurately and quantitatively evaluated. As a result, the minimum necessary dressing without excess or deficiency can be realized.

  Next, the dressing means 90 for the polishing pad will be described with reference to FIG. In this polishing pad dressing means 90, a pad dresser 90A to which abrasive grains such as diamond are attached is brought into contact with the polishing pad 50, and the surface of the polishing pad 50 is scraped off or the surface of the polishing pad 50 is roughened. Thus, a process for restoring the retention of the slurry and maintaining the polishing ability is performed.

  Since the polishing pad dressing means 90 is contact processing by the pad dresser 90A, in particular, the polishing pad 50 that has not been subjected to groove processing or the through hole for automatic end point detection of polishing processing is not provided. This is effective for dressing the polishing pad 50.

  The pad dresser 90A may be composed of a diamond abrasive grain 80B electrodeposited on the lower surface or a bond layer (metal bond, vitrified bond or resin bond) in which the abrasive grain 80B is dispersed. The pad dresser 90 </ b> A is pressed against the polishing pad 50 with a force F while being rotated about the shaft 92 to dress the polishing pad 50.

  The thickness of the pad dresser 90A is generally about 10 to 30 mm, and the outer diameter is generally about 100 to 250 mm (4 to 10 inches). The base of the pad dresser 90A is generally made of metal.

  And although illustration is abbreviate | omitted, it is preferable that the pad dresser 90A and the axis | shaft 92 are connected via the flexible joint (for example, universal joint: registered trademark). With this configuration, the surface (lower surface) of the pad dresser 90A and the surface of the polishing pad 50 are in contact with each other, and the surface of the pad dresser 90A follows the surface of the polishing pad 50 even during dressing work.

  Next, a polishing pad dressing evaluation method and a polishing pad dressing method using the polishing apparatus 10 configured as described above will be described. Here, an example in which the present invention is applied to polishing of a wafer by CMP will be described.

  As the polishing pad 50, a polishing pad for CMP, for example, one manufactured by Rodel (trade name: IC-1000) or one made by Freudenberg (trade name: FX-9) can be used. As the workpiece W, a silicon wafer can be used.

  As the stock solution of the abrasive slurry for CMP, for example, a product manufactured by Fujimi Incorporated (trade name: PL (PLANERLITE) -4217) can be used. As the phosphor to be added thereto, calcein or umbelliferone can be used, and the addition amount can be, for example, 2 g / L.

  After polishing the workpiece W (silicon wafer) for a predetermined time (for example, 10 hours), the slurry on the polishing pad 50 is removed (washed away), and then dressing of the polishing pad 50 is performed by the dressing means 90. The slurry remaining on the polishing pad 50 is detected by irradiating the polishing pad 50 with ultraviolet rays. This detection is performed based on the fluorescence luminance imaged by the camera system 29. Then, when the detected fluorescence luminance is equal to or lower than a predetermined threshold, it is determined that the dressing end level of the polishing pad 50 is reached. As a result, the minimum necessary dressing without excess or deficiency can be realized.

  Next, another embodiment (second embodiment) of the dressing property evaluation method for a polishing pad and the dressing method for a polishing pad according to the present invention will be described in detail. FIG. 3 is a front view of a polishing apparatus 10 ′ to which the polishing pad dressing evaluation method and the polishing pad dressing method of the present invention are applied, and FIG. 4 is a plan view of the same part.

  In the present embodiment, the slurry detection means 25 is the same as that of the first embodiment described above, and therefore the illustrations in FIG. 3 and FIG. 4 and the detailed description thereof are omitted.

  The dressing means for the polishing pad in FIGS. 3 and 4 is based on high-pressure spraying, and in particular, the polishing pad 50 provided with a groove and a polishing pad 50 provided with a through hole for automatic end point detection of polishing. Effective for dressing.

  As shown in FIGS. 3 and 4, the polishing apparatus 10 mainly includes a polishing surface plate 52, a wafer holding head 51 that holds a workpiece W, a slurry supply arm 53 that is a slurry supply unit, and a dressing unit for a polishing pad. It is comprised with the nozzle 14 (others, such as a pipe 16, pump 20).

  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, dressing means for the polishing pad will be described. The dressing means for the polishing pad includes a nozzle 14 and the like. The nozzle 14 is supported by the pump 20 via the arm 42 and the pipe 16. The dressing means for the polishing pad dresses the polishing pad 50 by spraying a cleaning liquid such as pure water from the dressing nozzle 14 onto the polishing pad 50 on the surface plate 52 of the polishing apparatus.

  The nozzle 14 is arranged at a predetermined distance from the surface of the polishing pad 50. FIGS. 5 and 6 illustrate the nozzle 14. FIG. 5 is a cross-sectional view of the nozzle 14 and FIG. 6 is a bottom view of the nozzle 14.

  The nozzle 14 includes a nozzle chip 36 having a discharge port 34 and a nozzle case 38 in which the nozzle chip 36 is inserted. As shown in FIG. 6, the discharge port 34 is vertically long and has an elliptical shape with a short diameter of 200 μm and a long diameter of 500 μm with the central portion expanding toward the front (lower side in FIG. 5).

  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, the nozzle 14 can be caused to swing in the left-right direction around the rotary stage 18 as the rotation center. The swinging motion of the nozzle 14 is controlled via a motor 30 by a control unit (not shown). FIG. 4 shows this oscillating motion, and the nozzle 14 can oscillate 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 37 provided on a base 35, and an end of the table 32 is connected to an air cylinder 39 supported by the base 35 via a rod 40. It is connected. Therefore, by operating the air cylinder 39, the nozzle 14 can be moved in the arrow a direction via the table 32 or the like.

  Note that the movement direction of the table 32 may be changed by changing the arrangement of the rail 37, the air cylinder 39, and the like, and the nozzle 14 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, a polishing pad dressing evaluation method and a polishing pad dressing method by the polishing apparatus 10 ′ configured as described above will be described. Here, as in the first embodiment described above, an example applied to polishing a wafer by CMP will be described. Accordingly, the description of the polishing pad 50 and the abrasive slurry is omitted.

  After polishing the workpiece W (silicon wafer) for a predetermined time (for example, 10 hours), the slurry on the polishing pad 50 is removed (washed away), and then dressing of the polishing pad 50 by dressing means, The slurry remaining on the polishing pad 50 is detected by irradiating the polishing pad 50 with ultraviolet light.

  When dressing the polishing pad 50, the air cylinder 39 is operated to position the nozzle 14 on the polishing pad 50, and the pump 20 is operated to spray the cleaning liquid from the nozzle 14. The cleaning liquid sprayed from the nozzles 14 is atomized and collides with the polishing pad 50, and the polishing debris accumulated in the polishing pad 50 is knocked out and washed away.

  Then, while the cleaning liquid is ejected from the nozzle 14, the polishing pad 50 is rotated by the motor 56 and the nozzle 14 is moved by the air cylinder 39. Thereby, the polishing pad 50 can be dressed over the entire surface.

  It is necessary to adjust the size of the mist of the cleaning liquid colliding with the polishing pad 50 and the collision speed according to the material of the polishing pad 50. For example, when the polishing pad 50 is made of hard porous polyurethane, the particle size of the mist of the cleaning liquid is preferably 1 μm or more and 300 μm or less, and more preferably 1 μm or more and 100 μm or less. This is because in order for the cleaning liquid mist to enter the hole clogged with the polishing dust of the polishing pad 50 and to wash away the polishing dust from there, the size of the mist is equal to or larger than the polishing dust and the polishing pad 50 It must be smaller than the hole.

  In other words, mist particles that are too small compared to the polishing debris have a weak force for washing away the polishing debris. On the other hand, since the mist larger than the hole of the polishing pad 50 cannot enter the hole as it is, the polishing debris clogged there cannot be beaten out.

  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. If the collision speed of the mist is too low, the kinetic energy is insufficient to beat out the polishing debris. On the other hand, if the collision speed of the mist is too high, the polishing pad 50 may be damaged. In order to realize the above-described size and collision speed of the cleaning liquid, it is preferable to supply the cleaning liquid to the nozzle 14 at a pressure of 15 MPa to 30 MPa.

  The size of the mist of the cleaning liquid and the collision speed with the polishing pad 50 can be controlled by adjusting the nozzle diameter of the nozzle 14 and the supply pressure of the cleaning liquid to the nozzle 14 by the pump 20.

  The distance between the tip of the nozzle 14 and the surface of the polishing pad 50 can be set to an appropriate value according to the nozzle diameter of the nozzle 14, the supply pressure of the cleaning liquid by the pump 20, the material of the polishing pad 50, the size of the polishing pad 50, and the like. For example, 100 mm can be adopted.

  As the cleaning liquid, pure water is generally used, but besides this, a PH adjusting liquid, a liquid obtained by removing abrasive grains from an abrasive slurry, or the like can also be used. As the pH adjusting liquid, an alkaline adjusting liquid, specifically, commercially available alkaline ionized water or the like can be used. As the liquid from which the abrasive grains are removed from the abrasive slurry, a liquid prepared without adding only the abrasive grains when the abrasive slurry is prepared can be used.

  The detection of the slurry remaining on the polishing pad 50 is performed in the same manner as in the first embodiment described above. Then, when the detected fluorescence luminance is equal to or lower than a predetermined threshold, it is determined that the dressing end level of the polishing pad 50 is reached. As a result, the minimum necessary dressing without excess or deficiency can be realized.

  Next, still another embodiment (third embodiment) of the polishing pad dressing evaluation method and the polishing pad dressing method according to the present invention will be described in detail. FIG. 7 is a front view of a polishing apparatus 10 ″ to which the dressing evaluation method and the polishing pad dressing method of the present invention are applied, and FIG. 8 is a plan view of the same part. FIG. 9 is a cross-sectional view of the nozzle 114.

  In the present embodiment, the slurry detection means 25 is the same as that of the first embodiment described above, and therefore, illustrations and detailed descriptions in FIGS. 7 and 8 are omitted. The same or similar members as those in the first and second embodiments are similarly denoted by the same reference numerals, and detailed description thereof is omitted.

  Since the dressing means for the polishing pad in FIGS. 7 and 8 is based on the spray of two fluids, in particular, polishing with a polishing pad 50 that has been grooved and a through hole for automatic end point detection of the polishing process is provided. This is effective for dressing the pad 50.

  Next, dressing means for the polishing pad will be described. The polishing pad dressing means includes a pad dresser 60 and a nozzle 114. Among these, the pad dresser 60 has the same specifications as the pad dresser 90A described above.

  The nozzle 114 has a discharge port 122. The compressed air supplied from the compressed air supply port 124 and the cleaning water supplied from the cleaning water supply port 126 are mixed in the nozzle 114 and atomized from the discharge port 122. It is the structure of ejecting.

  Various patterns such as a circular pattern, an oval or oval pattern, a rectangular pattern, etc. can be adopted as the spray pattern (spray pattern) ejected from the discharge port 122, and according to this, the type of the nozzle 114 has various specifications. Things can be adopted.

  One end of a flexible pressure-resistant hose 15 that is a compressed air supply pipe is connected to the compressed air supply port 124 of the nozzle 114, 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-resistant hose 15 is not shown in FIG.

  The nozzle 114 is connected to the pump 20 via the pipe 16, and the pump 20 is connected to the tank 24 via the flexible hose 22. The cleaning liquid stored in the tank 24 is pressurized by the pump 20 and sent to the nozzle 114, 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 114 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 114 and the pad dresser 60 is controlled via the motor 30 by a control unit (not shown). FIG. 8 shows this oscillating motion, and the nozzle 114 and the pad dresser 60 can oscillate 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 37 provided on a base 35, and an end of the table 32 is connected to an air cylinder 39 supported by the base 35 via a rod 40. It is connected. Therefore, by operating the air cylinder 39, the nozzle 114 and the pad dresser 60 can be moved in the arrow a direction via the table 32 or the like.

  As the cleaning liquid sprayed from the nozzle 114, 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, a polishing pad dressing evaluation method and a polishing pad dressing method using the polishing apparatus 10 ″ configured as described above will be described. Here, as in the first embodiment described above, an example applied to polishing a wafer by CMP will be described. Accordingly, the description of the polishing pad 50 and the abrasive slurry is omitted.

  After polishing the workpiece W (silicon wafer) for a predetermined time (for example, 10 hours), the slurry on the polishing pad 50 is removed (washed away), and then dressing of the polishing pad 50 by dressing means, The slurry remaining on the polishing pad 50 is detected by irradiating the polishing pad 50 with ultraviolet light.

  When dressing the polishing pad 50, the pad dresser 60 is pressed onto the polishing pad 50, and the pump 24 and the compressed air supply source 15A are operated to inject the cleaning liquid from the nozzle 114.

  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 114 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.

  As described above, the polishing pad 50 (polishing surface plate 52) is rotated in the direction of the arrow in FIG. 8 while rotating the pad dresser 60 and spraying the cleaning liquid from the nozzle 114. Further, by dressing the arm 42 while swinging in the directions of arrows d and e in FIG. 8, the entire surface of the polishing pad 50 is dressed without draining 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.

  For this reason, the supply pressure of the cleaning liquid to the nozzle 114 can be set to 0.5 MPa, for example, and the supply pressure of the compressed air to the nozzle 114 can be set to 1.0 MPa, for example.

  The detection of the slurry remaining on the polishing pad 50 is performed in the same manner as in the first embodiment described above. Then, when the detected fluorescence luminance is equal to or lower than a predetermined threshold, it is determined that the dressing end level of the polishing pad 50 is reached. As a result, the minimum necessary dressing without excess or deficiency can be realized.

  Next, still another embodiment (fourth embodiment) of the polishing pad dressing evaluation method and the polishing pad dressing method according to the present invention will be described in detail. FIG. 10 is a plan view of an essential part of a polishing apparatus 10 ′ ″ to which the polishing pad dressing evaluation method and the polishing pad dressing method of the present invention are applied. FIG. 11 is a sectional view of the nozzle 214.

  In addition, in this embodiment, since the slurry detection means 25 is the same as 1st Embodiment mentioned above, illustration to FIG. 10 and detailed description are abbreviate | omitted. In addition, members that are the same as or similar to those in the first, second, and third embodiments are denoted by the same reference numerals, and detailed descriptions thereof are omitted.

  The present embodiment differs from the third embodiment in the configuration of the dressing means (pad dresser 60 and nozzle 214) and the configuration of the slurry supply arm 53.

  First, the nozzle 214 will be described. As shown in FIG. 11, the nozzle 214 includes a nozzle body 216, which is a cylindrical member whose inner diameter increases from the substantially central portion toward the rear (base end portion), and a predetermined clearance in the inner peripheral portion of the nozzle body 216. The inner tube 218 is inserted and fixed.

  The base ends of the nozzle body 216 and the inner tube 218 are a compressed air supply port 216A and a cleaning water supply port 218A, 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 tube 218.

  As for the dressing means, in this embodiment, the pad dresser 60 is rotatably supported at the tip of the arm 42 as in the third embodiment, but the nozzle 214 is different from the third embodiment. It is fixed to the side of the arm 42. The cleaning liquid is supplied to the nozzle 214 from the pump 20 (see FIG. 7) through the supply pipe 14A.

  Note that, unlike the third embodiment, the arm 42 is configured to be rotated by a rotation means (not shown) around the rotation center 42A.

  Although the configuration of the dressing means described above is different from that of the third embodiment, this basic action is substantially the same as that of the third embodiment. The operation of the dressing means for the polishing pad (pad dresser 60 and nozzle 214) configured as described above is substantially the same as that of the third embodiment, and thus the description thereof is omitted.

  The slurry supply nozzle 53A is fixed to the tip of the slurry supply arm 53 as in the third embodiment, but in this embodiment, in addition to this, six rinse liquid supply nozzles 55, 55... Are fixed to the lower surface of the slurry supply arm 53 at a predetermined interval.

  Due to the configuration of the slurry supply arm 53 described above, unlike the third 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. 10, 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 214 or after dressing by the nozzle 214, 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. It is preferable that the supply flow rate of the rinse liquid is larger than the flow rate of the cleaning liquid ejected from the nozzle 214. 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 214 is 1 liter / minute, the supply flow rate of the rinsing liquid is preferably 2 to 100 liters / minute. Will change.

  The detection of the slurry remaining on the polishing pad 50 is performed in the same manner as in the first embodiment described above. Then, when the detected fluorescence luminance is equal to or lower than a predetermined threshold, it is determined that the dressing end level of the polishing pad 50 is reached. As a result, the minimum necessary dressing without excess or deficiency can be realized.

  Next, another embodiment (fifth embodiment) of the polishing pad dressing evaluation method and the polishing pad dressing method according to the present invention will be described in detail. FIG. 12 is a plan view of an essential part of a polishing apparatus 10 ″ ″ ″ to which the polishing pad dressing evaluation method and the polishing pad dressing method of the present invention are applied. FIG. 13 is a cross-sectional view of the nozzle 314.

  In addition, in this embodiment, since the slurry detection means 25 is the same as 1st Embodiment mentioned above, illustration to FIG. 12 and detailed description are abbreviate | omitted. The same or similar members as those in the first, second, third, and fourth embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

  This embodiment is different from the fourth embodiment in the configuration of the nozzle 314 of the dressing means (the type and fixing method of the nozzle 314). That is, the nozzle 314 is common to the fourth embodiment in that the nozzle 314 is arranged on the side surface of the arm 42, but the nozzle 314 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 314 is performed from the pump 20 (see FIG. 7) through the supply pipe 14A.

  As shown in FIG. 13, the nozzle 314 is a flowing water type ultrasonic cleaning machine, and includes a nozzle body 316, a cleaning water supply port 318 formed on a side surface of the nozzle body 316, and a rear end portion inside the nozzle body 316. Are provided with an ultrasonic transducer 320, a drive circuit (not shown) for driving the ultrasonic transducer 320, and a discharge port 322 formed at the tip of the nozzle body 316.

  In the nozzle 314, the cleaning water supplied from the cleaning water supply port 318 is applied with ultrasonic vibration 324 by the ultrasonic vibrator 320, and is atomized and ejected from the discharge port 322 in this state.

  As the type of the nozzle 314, nozzles having various specifications can be adopted depending on the spray pattern, the effect of the ultrasonic vibration 324, 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. However, depending on the type of polishing pad 50, the type of slurry, etc. It is necessary to change the frequency and output.

  The detection of the slurry remaining on the polishing pad 50 is performed in the same manner as in the first embodiment described above. Then, when the detected fluorescence luminance is equal to or lower than a predetermined threshold, it is determined that the dressing end level of the polishing pad 50 is reached. As a result, the minimum necessary dressing without excess or deficiency can be realized.

  The operation of the fifth 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. 12 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 314 is Dressing is performed.

  At this time, the nozzle 314 can be slid in the longitudinal direction while the position of the pad dresser 60 is fixed. Accordingly, the cleaning liquid is ejected from the nozzle 314 toward the polishing pad 50 while the position of the pad dresser 60 is fixed, so that the substantially entire surface of the polishing pad 50 can be dressed.

  As described above, according to the fifth 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 324 is applied is applied from the nozzle 314 to the polishing pad 50. 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.

  Further, since the cleaning liquid applied with the ultrasonic vibration 324 collides with the polishing pad 50 so that 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.

  As mentioned above, although each embodiment of the dressing property evaluation method of a polishing pad and the dressing method of a polishing pad concerning this invention was described, this invention is not limited to the said embodiment, Various aspects can be taken.

  For example, in this embodiment, calcein or umbelliferone is used as the phosphor to be added to the slurry, but other phosphors can also be used.

  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).

  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.

  The dressing property of the polishing pad was evaluated using the polishing apparatus 10 shown in FIG. The abrasive slurry used for polishing is a product manufactured by Fujimi Incorporated (trade name: PL (PLANERLITE) -4217) diluted to a weight ratio of 25% and injected with 2 g of calcerin as a phosphor per liter. did.

  Carserine is a metal indicator that is a fusion of two iminodiacetic acids with fluorescein. It is easily dissolved in an alkaline aqueous solution and emits strong yellow-green fluorescence having a peak wavelength of 450 nm when irradiated with UV light.

  When evaluating the dressing property of the polishing pad in the polishing apparatus 10 of FIG. 1, a glass wafer was used as a workpiece (workpiece). Then, as shown in FIG. 14, the polishing pad 50 can be evaluated through the glass wafer G.

  The detected light emission signal means that if the thickness of the slurry under the glass wafer G is thick, the intensity of the light emission signal is increased and the slurry residue inside the pad groove is increased.

  The experimental procedure (flow) is shown in the flowchart of FIG. 15, and the processing conditions and dressing conditions are shown in the table of FIG.

  First, using a # 100 count (100 grid) diamond disc, break-in dressing is performed for 30 minutes for pad habituation while dripping ultrapure water (step S-1).

  Next, in order to leave the fluorescent slurry in a groove (groove) of the polishing pad 50, continuous polishing is performed with the slurry for 10 hours while dropping the fluorescent slurry (step S-2).

  After the continuous polishing process, the slurry is fixed in the groove of the polishing pad 50, and left to stand for 24 hours in a dark room and dried at room temperature in order to make the slurry remain in the pad groove in a pseudo manner (step S-3).

  After the polishing pad 50 was dried for 24 hours, the surface of the pad was photographed through a glass wafer G with a CCD camera and the fluorescence emission intensity in the measurement area was measured. The groove portion was compared with the portion other than the groove, The emission signal was strong, and it was confirmed that slurry residue remained in the groove.

  In order to compare the removal ability of the slurry left in the groove of the polishing pad 50 between the conventional diamond dressing (step S-4) and the spray dressing (step S-5), dressing is performed every 30 seconds, and the emission intensity is set. taking measurement.

  The wafer to be processed (work W) is obtained by forming an oxide film on a silicon wafer, the wafer pressure (processing pressure) is 20.7 kPa (3 psi), and the relative speed between the polishing pad 50 and the wafer is 0.62 m / Second, and the slurry flow rate is 80 ml / min.

  As the polishing pad 50, a black pad was used to detect fluorescence, and a pad processed by Freudenberg (model number: FX-9) grid and concentric grooves was used. . When the cross-section of each pad groove is observed with a microscope in advance, the grid-like groove of the grid has a groove width of 0.7 mm and a depth of 1.12 mm, and the concentric groove has a groove width of 0.2 mm and a depth. It was 0.45 mm.

  The dressing method was ex-situ dressing for both diamond dressing and spray dressing.

  In the dressing with a diamond disk (step S-4), a 100 grid TBW diamond disk is used, the pressure is set to 3.5 kPa, the reciprocating cycle of the disk is set to 20 times per minute, and the number of rotations of the diamond disk is set. Dressing was carried out while dropping at 30 rpm and a conventional Fujimi Incorporated product (PL-4217, slurry weight ratio 25%) into which calcein was not injected at a flow rate of 80 ml / min.

  On the other hand, in the spray dressing (step S-5), the spraying pressure is 10 MPa, the distance between the nozzle and the pad is 10 mm, the spraying fan angle of the nozzle is 15 degrees, and when spraying from the nozzle at 10 MPa, 1.15 liter / Using a nozzle with a flow rate of minutes, ultrapure water was sprayed to perform dressing. The reciprocating cycle of the nozzle was 10 times / minute.

  17 is a graph showing the results of the dressing property evaluation of the polishing pad, and shows the light intensity (Intensity AU) after performing each dressing every 30 seconds. Among these, (A) is of a grid-like groove on the grid, and (B) is of a concentric groove. In each graph, the results of diamond dressing and spray dressing are shown.

  In FIG. 17A of the grid-like grooves on the grid, the light intensity is saturated at about 180 (AU) in 90 seconds in both the diamond dressing and the spray dressing. That is, the slurry residue in the pad groove is removed in 90 seconds.

  In FIG. 17B of concentric grooves, in the case of spray dressing, the light intensity is saturated at 180 (AU) in 90 seconds as in (A), whereas in diamond dressing, In this case, the light intensity at 90 seconds is 210 (AU), and is saturated at 180 (AU) at 150 seconds.

  That is, it can be seen that in the concentric groove pad dressing, the efficiency of removing the slurry residue at the bottom of the pad groove is lower in the diamond disk than in the spray dressing.

  The opening of the grid-like grooves on the grid is 0.7 mm, whereas the concentric grooves have a groove width of 0.2 mm. Therefore, as shown in FIG. Since it does not reach the bottom of the pad groove 50G, it becomes difficult to clean the pad groove bottom.

  On the other hand, in the case of a grid-like groove on the grid, the bottom of the groove can be cleaned by tilting the diamond disk or deforming the pad. In the case of spray dressing, it can be seen that it is effective for cleaning a narrow groove opening such as a concentric groove type.

1 is a perspective view of a polishing apparatus to which a dressing property evaluation method for a polishing pad and a dressing method for a polishing pad according to the present invention are applied. Front view of polishing pad dressing means Front view of another polishing apparatus to which dressing property evaluation method for polishing pad and dressing method for polishing pad of the present invention are applied FIG. 3 is a plan view of the main part of the polishing apparatus of FIG. Cross section of nozzle Nozzle bottom view Front view of still another polishing apparatus to which the dressing evaluation method for a polishing pad and the dressing method for a polishing pad according to the present invention are applied. FIG. 7 is a plan view of the main part of the polishing apparatus. Cross section of nozzle The principal part top view of the further another polishing apparatus to which the dressing property evaluation method of the polishing pad of this invention and the dressing method of a polishing pad are applied Cross section of nozzle The principal part top view of the further another polishing apparatus to which the dressing property evaluation method of the polishing pad of this invention and the dressing method of a polishing pad are applied Cross section of nozzle The figure which shows the state which transmits a glass wafer and evaluates a polishing pad The figure which shows the flow of dressing property evaluation of a polishing pad Table showing conditions for evaluating dressing properties of polishing pads Graph showing results of dressing evaluation of polishing pad Partial enlarged view showing the cross-sectional shape of the groove of the polishing pad

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Polishing apparatus 14, 114, 214, 314 ... Nozzle, 15 ... Flexible pressure hose, 16 ... Pipe, 20 ... Pump, 22 ... Hose, 24 ... Tank, 25 ... Slurry detection means, 27 ... UV lamp, 29 ... Camera system 45 ... pump 47 ... slurry pipe 49 ... slurry tank 50 ... polishing pad 51 ... wafer holding head 52 ... polishing platen 53 ... slurry supply arm 60 ... pad dresser W ... workpiece

Claims (12)

A method of evaluating the dressing property of the polishing pad when dressing the polishing pad in a polishing apparatus that performs polishing by bringing a workpiece into contact with the polishing pad while supplying slurry,
After performing polishing by adding a phosphor to the slurry, the dressing property of the polishing pad is evaluated by detecting the slurry remaining on the polishing pad by irradiating the polishing pad with ultraviolet rays. A method for evaluating dressing properties of a polishing pad.   The polishing pad dressing evaluation method according to claim 1, wherein after the polishing process, the ultraviolet light is irradiated after the slurry on the polishing pad is poured off.   The method for evaluating dressing properties of a polishing pad according to claim 1, wherein the phosphor is calcein or umbelliferone. A polishing pad dressing method for performing dressing of the polishing pad according to an evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3,
A polishing pad dressing method characterized in that a cleaning liquid having a particle size of 1 μm or more and 300 μm or less is ejected from a nozzle and collides with 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. . A polishing pad dressing method for performing dressing of the polishing pad according to an evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3,
Dressing the polishing pad by pressing a pad dresser against the polishing pad, and mixing two or more fluids including a cleaning liquid and a gas, and ejecting the polishing pad from the nozzle toward the polishing pad. A polishing pad dressing method characterized by the above. A polishing pad dressing method for performing dressing of the polishing pad according to an evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3,
The polishing pad is dressed by pressing a pad dresser against the polishing pad, and the polishing pad is dressed by ejecting a cleaning liquid to which ultrasonic vibration is applied from the nozzle toward the polishing pad. Polishing pad dressing method. A polishing pad dressing method for performing dressing of the polishing pad according to an evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3,
A polishing pad dressing method, wherein a dressing of the polishing pad is performed by pressing a pad dresser, which is a plate-like body having a large number of diamond abrasive grains fixed on the surface, against the polishing pad. A polishing pad dressing method for performing dressing of the polishing pad according to an evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3,
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 for performing dressing of the polishing pad according to an evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3,
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 for performing dressing of the polishing pad according to an evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3,
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 for performing dressing of the polishing pad according to an evaluation result by the dressing property evaluation method of the polishing pad according to claim 1, 2 or 3,
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. 12. The polishing pad dressing method according to claim 4, wherein dressing of the polishing pad is performed simultaneously with the polishing process.

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