JP2019042835A - Method and device for polishing substrate - Google Patents

Abstract

To provide a method for polishing a peripheral edge part of a substrate that can prevent clogging of a polishing tool at polishing by increasing the polishing speed thereof and reduce an amount of use of the polishing tool, and to provide a polishing device.SOLUTION: A method for polishing a peripheral edge part of a substrate W includes: holding the substrate W with a substrate holding part 10; and circularly moving a polishing tool support structure that constitutes at least part of a polishing head 50 while the polishing head 50 brings a polishing tape 31 into contact with the peripheral edge part of the substrate W to polish the peripheral edge part of the substrate W.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a polishing method and a polishing apparatus for polishing a substrate such as a semiconductor wafer, and more particularly to a polishing method and a polishing apparatus for polishing a peripheral portion of a substrate.

  From the viewpoint of yield improvement in the manufacture of semiconductor devices, management of the surface state of a substrate has recently attracted attention. In the semiconductor device manufacturing process, various materials are deposited on a silicon wafer. For this reason, an unnecessary film | membrane and surface roughening are formed in the peripheral part of a board | substrate. In recent years, a method of transporting a substrate by holding only the peripheral portion of the substrate with an arm has become common. Under such a background, the unnecessary film remaining on the peripheral portion is peeled off during various steps and adheres to the device formed on the substrate, which lowers the yield. Therefore, in order to remove an unnecessary film formed on the peripheral portion of the substrate, the peripheral portion of the substrate is polished using a polishing apparatus.

  This type of polishing apparatus polishes the peripheral portion of a substrate by bringing a polishing tool into sliding contact with the peripheral portion of the substrate. Specifically, the substrate is held on a stage, and the peripheral portion of the substrate is polished by pressing a polishing tool such as a polishing tape against the peripheral portion of the substrate by a polishing head while rotating or swinging the stage.

JP, 2006-303112, A

  However, the conventional apparatus described above has problems such as slow polishing speed and clogging of the polishing tool during polishing. In addition, it is required to reduce the amount of use of the polishing tool from the viewpoint of cost reduction.

  The present invention has been made to solve the above-mentioned conventional problems, and by effectively using the polishing tool, it is possible to increase the polishing rate and prevent clogging of the polishing tool during polishing. An object of the present invention is to provide a method and apparatus for polishing the peripheral portion of a substrate which can reduce the amount of use of a polishing tool.

  In order to achieve the above-described object, one aspect of the present invention is a method of polishing the peripheral portion of a substrate, wherein the substrate holding portion holds the substrate and a polishing head applies a polishing tool to the peripheral portion of the substrate. According to another aspect of the present invention, there is provided a polishing method comprising: rotating a polishing tool supporting structure constituting at least a part of the polishing head while making contact, and polishing the peripheral portion of the substrate.

A preferred aspect of the present invention is characterized in that the circular motion is a translational rotational motion.
A preferred embodiment of the present invention is characterized in that the peripheral portion of the substrate is a bevel of the substrate.
In a preferred aspect of the present invention, the peripheral portion of the substrate is a notch of the substrate.
A preferred embodiment of the present invention is characterized in that the polishing tool support structure is the entire polishing head.
In a preferred aspect of the present invention, the polishing head has a pressing mechanism for pressing the polishing tool against the peripheral portion of the substrate, and the polishing tool support structure is the pressing mechanism. I assume.
In a preferred aspect of the present invention, the polishing tool is a polishing tape having abrasive grains on the surface, and the polishing tool support structure is a plurality of guide rollers for supporting the polishing tape.

  One aspect of the present invention circularly moves a substrate holding portion for holding a substrate, a polishing head for bringing a polishing tool into contact with the peripheral portion of the substrate, and a polishing tool support structure that constitutes at least a part of the polishing head. And a circular motion mechanism.

In a preferred aspect of the present invention, the circular motion mechanism is a translation and rotation mechanism that translates and rotates the polishing tool support structure.
In a preferred aspect of the present invention, the circular motion mechanism is coupled to the polishing head, and the polishing tool support structure is the entire polishing head.
In a preferred aspect of the present invention, the polishing head has a pressing mechanism for pressing the polishing tool against the peripheral portion of the substrate, and the polishing tool support structure is the pressing mechanism. I assume.
In a preferred aspect of the present invention, the polishing tool is a polishing tape having abrasive grains on the surface, and the circular motion mechanism is connected to a plurality of guide rollers supporting the polishing tape, and the polishing tool support structure The body is characterized by being the plurality of guide rollers.

  According to the present invention, since the polishing tool is moved relative to the peripheral portion of the substrate by circularly moving the polishing tool support structure, the polishing tool can be used effectively. As a result, the polishing speed can be increased, and clogging of the polishing tool during polishing can be prevented. Furthermore, since the polishing tool can be effectively used, the usage amount of the polishing tool can be reduced and the life of the polishing tool can be improved.

FIG. 1A and FIG. 1B are enlarged cross-sectional views showing the peripheral portion of the substrate. It is a top view which shows the notch part of a board | substrate typically. It is a schematic diagram which shows one Embodiment of a grinding | polishing apparatus. It is a schematic diagram which shows one Embodiment of the circular motion mechanism for circularly moving a grinder support structure. It is a schematic diagram which shows an example of a grinding | polishing tape. It is a schematic diagram which shows the other example of an abrasive tape. FIG. 4 is a schematic view of the polishing head assembly shown in FIG. 3 as viewed from above. It is a schematic diagram which shows the state which inclined the grinding head and the circular motion mechanism upwards by the tilt mechanism. It is a schematic diagram which shows the state which inclined the grinding head and the circular motion mechanism downward by the tilt mechanism. It is a schematic diagram which shows other embodiment of a grinding | polishing apparatus. It is a schematic diagram which shows other embodiment of a grinding | polishing apparatus. It is a schematic diagram which shows other embodiment of a grinding | polishing apparatus. It is the schematic diagram which looked at operation | movement of the board | substrate when driving a swing mechanism from the upper direction of a board | substrate. It is a schematic diagram which shows the state which inclined the grinding head and the circular motion mechanism upwards by the tilt mechanism. It is a schematic diagram which shows the state which inclined the grinding head and the circular motion mechanism downward by the tilt mechanism. It is a schematic diagram which shows other embodiment of a grinding | polishing apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In this specification, in order to specify the crystal orientation, the peripheral portion of the substrate is identified by the bevel portion located at the outermost periphery of the substrate, the top edge portion and the bottom edge portion located radially inward of the bevel portion, and It is defined as a region including notches formed in the peripheral portion.

  FIG. 1A and FIG. 1B are enlarged cross-sectional views showing the peripheral portion of the substrate. More specifically, FIG. 1 (a) is a cross-sectional view of a so-called straight type substrate, and FIG. 1 (b) is a cross-sectional view of a so-called round type substrate. In the substrate W of FIG. 1A, the bevel portion is a substrate W including an upper inclined portion (upper bevel portion) P, a lower inclined portion (lower bevel portion) Q, and a side portion (apex) R. It is the outermost circumferential surface (indicated by a symbol B). In the substrate W of FIG. 1B, the beveled portion is a portion (indicated by reference numeral B) having a curved cross section which constitutes the outermost peripheral surface of the substrate W. The top edge portion is a flat portion E1 located radially inward of the bevel portion B. The bottom edge portion is a flat portion E2 located on the opposite side to the top edge portion and located radially inward of the bevel portion B. The top edge portion E1 may include an area in which a device is formed.

  FIG. 2 is a plan view schematically showing the notch portion of the substrate. In the substrate W of FIG. 2, the notch portion is a notch formed in the peripheral portion indicated by reference numeral N. The polishing apparatus for polishing the peripheral portion of the substrate can be roughly classified into a bevel polishing apparatus for polishing the bevel portion and a notch polishing apparatus for polishing the notch portion.

  FIG. 3 is a schematic view showing an embodiment of the polishing apparatus. The polishing apparatus shown in FIG. 3 is suitably used in a bevel polishing apparatus for polishing a bevel portion which is a peripheral portion of a substrate. As shown in FIG. 3, the polishing apparatus holds the substrate W which is a polishing target, and polishes a bevel portion of the substrate W held by the substrate holding unit 10 and the substrate holding unit 10 to rotate. And a polishing head assembly 49 for removing foreign matter and scratches from the bevel portion.

  In FIG. 3, a state in which the substrate holding unit 10 holds the substrate W is shown. The substrate holding unit 10 includes a holding stage 4 for holding the substrate W by vacuum suction, a shaft 5 connected to the central portion of the holding stage 4, and a holding stage drive mechanism 7 connected to the lower end of the shaft 5. ing.

  The holding stage drive mechanism 7 includes a motor and an air cylinder (not shown) for rotating and moving the holding stage 4 up and down. That is, the holding stage drive mechanism 7 is configured to be capable of rotating the holding stage 4 about its axis Cr and moving the holding stage 4 up and down along the axis Cr.

  The substrate W is mounted on the upper surface of the holding stage 4 by a transfer mechanism (not shown) such that the center O1 of the substrate W is on the axis Cr of the holding stage 4. The substrate W is held on the upper surface of the holding stage 4 with its surface (device surface) facing upward. With such a configuration, the substrate holding unit 10 rotates the substrate W around the axis Cr of the holding stage 4 (that is, the axis of the substrate W), and along the axis Cr of the holding stage 4. It can be raised and lowered.

  The polishing head assembly 49 has a polishing head 50 for polishing the bevel portion of the substrate W by bringing the polishing tape 31 which is an example of the polishing tool into contact with the bevel portion of the substrate W held by the substrate holder 10; A circular motion mechanism 61 is provided to cause the structure to circularly move relative to the substrate W. In the present specification, the polishing tool support structure is defined as a structure that supports the polishing tool and constitutes at least a part of the polishing head 50. In the present embodiment, the polishing tool is the polishing tape 31, and the polishing tool support structure is the entire polishing head 50. The polishing head 50 faces the peripheral portion of the substrate W when the substrate W is held by the substrate holding unit 10.

  FIG. 4 is a schematic view showing an embodiment of a circular movement mechanism 61 for circularly moving the polishing tool support structure. A circular motion mechanism 61 shown in FIG. 4 includes a motor 62, an eccentric rotary body 65 fixed to a rotary shaft 63 of the motor 62, a table 69 connected to the eccentric rotary body 65 via a bearing 67, and a table 69. A plurality of cranks 70 to support is provided. Although only one crank 70 is shown in FIG. 4, at least three cranks 70 are arranged around the eccentric rotor 65. The motor 62 is fixed to the base 71.

  The axial center 65 a of the eccentric rotary body 65 is separated from the axial center 63 a of the rotation shaft 63 of the motor 62 by a distance e. Thus, when the motor 62 is actuated, the eccentric rotator 65 performs a circular motion of radius e. The crank 70 has a first shaft 72 and a second shaft 73 fixed to each other. The axis 72 a of the first shaft 72 and the axis 73 a of the second shaft 73 are also separated by the distance e. The first shaft body 72 is rotatably supported by a bearing 75 held on a table 69, and the second shaft body 73 is rotatably supported by a bearing 77. The bearing 77 is fixed to a support member 79 fixed to the base 71.

  According to the above configuration, when the motor 62 rotates, the eccentric rotating body 65 performs circular movement of the radius e, and the table 69 connected to the eccentric rotating body 65 via the bearing 67 also performs circular movement of the radius e. Circular motion is defined herein as motion in which an object moves on a circular orbit.

  Since the table 69 is supported by the plurality of cranks 70, the table 69 itself does not rotate when the table 69 is performing a circular motion. Such movement of the table 69 is also referred to as translational rotational movement. In the present specification, the movement of an object moving on a circular orbit without rotation of the object itself is defined as translational rotation movement. This translational rotational movement is an example of circular movement. In the present embodiment, the polishing head 50 is fixed to the table 69 via the holding member 89. Thus, the polishing head 50 performs circular motion (translational rotational motion) with the table 69. In the present embodiment, the circular motion mechanism 61 is a translational rotation mechanism that causes the polishing tool support structure (the entire polishing head 50) to translate and rotate. The circular movement (translational rotational movement) in the present embodiment is a circular movement (translational rotational movement) in a plane in which the direction of the polishing head 50 is a normal direction.

  Returning to FIG. 3, the polishing apparatus of the present embodiment supplies the partition 100 and the polishing tool supply and recovery mechanism 41 for supplying the polishing tape 31 to the polishing head 50 and recovering it from the polishing head 50, and It further comprises a liquid supply nozzle 28 for supplying. The substrate holding unit 10, the polishing head assembly 49, and the liquid supply nozzle 28 are disposed inside the partition 100, and the polishing tool supply and recovery mechanism 41 is disposed outside the partition 100.

  In the present embodiment, a polishing tape 31 having abrasive grains on the surface is used as a polishing tool. FIG. 5 is a schematic view showing an example of the polishing tape 31. As shown in FIG. The polishing tape 31 shown in FIG. 5 has a base tape 33 and a polishing layer 35. The surface of the base tape 33 is covered with the polishing layer 35. The polishing layer 35 includes abrasive grains 37 and a binder (resin) 39 that holds the abrasive grains 37. The surface of the polishing layer 35 constitutes a polishing surface for polishing the substrate W. FIG. 6 is a schematic view showing another example of the polishing tape 31. As shown in FIG. The abrasive tape 31 shown in FIG. 6 has a base tape 33, an abrasive layer 35, and an elastic layer 40 located therebetween. The elastic layer 40 is made of an elastic material such as non-woven fabric made of polypropylene, polyurethane, polyester or nylon, or silicone rubber.

  Returning to FIG. 3, the polishing tool supply and recovery mechanism 41 includes a supply reel 43 for supplying the polishing tape 31 to the polishing head 50 and a recovery reel 44 for recovering the polishing tape 31 used for polishing the substrate W. . A tension motor (not shown) is connected to the supply reel 43 and the recovery reel 44 respectively. Each tension motor can apply a predetermined torque to the supply reel 43 and the recovery reel 44 and apply a predetermined tension to the polishing tape 31.

  The polishing tape 31 is supplied to the polishing head 50 such that the polishing surface of the polishing tape 31 faces the surface to be polished of the bevel portion of the substrate W. The polishing tape 31 is supplied from the supply reel 43 to the polishing head 50 through an opening (not shown) provided in the partition 100, and the used polishing tape 31 is collected on the collection reel 44 through the opening.

  The polishing head 50 includes a pressing mechanism 52 that presses the polishing tape 31 against the bevel portion of the substrate W. The polishing tape 31 is supplied so as to pass through the end surface of the pressing mechanism 52. In the present embodiment, the pressing mechanism 52 includes a pressing pad 52a for supporting the back surface of the polishing tape 31, and an air cylinder 52b connected to the pressing pad 52a. In one embodiment, the polishing tool may be a grindstone instead of the polishing tape 31. In this case, the grindstone is held by the air cylinder 52b constituting the pressing mechanism 52, and the polishing tool supply and recovery mechanism 41 and the pressing pad 52a can be omitted.

  The pressing mechanism 52 presses the polishing tape 31 from its back side and brings the polishing surface of the polishing tape 31 into contact with the bevel portion of the substrate W, thereby polishing the bevel portion of the substrate W. The polishing head 50 further includes a plurality of guide rollers 53 a, 53 b, 53 c, 53 d, 53 e, 53 f for supporting the polishing tape 31. The polishing tool supply and recovery mechanism 41 further includes a plurality of guide rollers 53 g and 53 h for supporting the polishing tape 31. The advancing direction of the polishing tape 31 is guided by guide rollers 53a, 53b, 53c, 53d, 53e, 53f, 53g, 53h. In particular, the guide rollers 53a and 53c disposed at the tip of the polishing head 50 guide the polishing tape 31 so that the polishing tape 31 advances in the direction parallel to the polishing surface of the bevel portion of the substrate W.

  The liquid supply nozzle 28 is disposed above the substrate W held by the substrate holder 10. The liquid supply nozzle 28 is connected to a liquid supply not shown. The liquid supply nozzle 28 is disposed facing the center O1 of the substrate W, and the liquid is supplied to the surface of the substrate W from the liquid supply nozzle 28. The liquid supplied to the surface of the substrate W spreads over the entire surface of the substrate W by centrifugal force to form a flow of liquid on the bevel portion of the substrate W. The beveled portion of the substrate W is polished in the presence of liquid. The liquid flows downward from the peripheral portion of the substrate W, whereby polishing debris can be removed from the beveled portion of the substrate W. Further, the above-described liquid prevents the liquid including polishing debris and foreign matter generated by the polishing of the substrate W from adhering to the surface of the substrate W. As a result, the surface of the substrate W can be kept clean. In the present embodiment, pure water or alkaline water is used as the above-mentioned liquid.

  FIG. 7 is a schematic view of the polishing head assembly 49 shown in FIG. 3 as viewed from above. As shown in FIG. 7, the polishing head assembly 49 further includes a tilt mechanism 81 for tilting the polishing head 50 with respect to the surface of the substrate W on the substrate holding unit 10. The circular motion mechanism 61 is fixed to the tilt mechanism 81, and the polishing head 50 is fixed to the circular motion mechanism 61 via the holding member 89. The polishing head 50 may be directly fixed to the circular motion mechanism 61.

  The tilt mechanism 81 includes a rotational drive device 82 and a crank arm 85. The rotational drive device 82 includes a motor, a pulley, a belt, and the like (not shown). One end of the crank arm 85 is connected to the circular motion mechanism 61, and the other end is connected to the rotary drive 82. The crank arm 85 is rotated about the rotation axis Ct of the rotary drive 82. The rotation axis Ct extends in the tangential direction of the substrate W on the substrate holder 10. When the rotary drive 82 rotates the crank arm 85 clockwise and counterclockwise about the rotation axis Ct by a predetermined angle, the circular motion mechanism 61 and the polishing head 50 connected to the crank arm 85 also rotate about the rotation axis Ct. Rotate clockwise and counterclockwise about a predetermined angle.

  The polishing surface of the polishing tape 31 supported by the polishing head 50 is located on the extension of the rotation axis Ct of the rotation drive device 82. Therefore, when the rotation drive device 82 is driven, the polishing head 50 rotates clockwise and counterclockwise around the polishing surface of the polishing tape 31 by a predetermined angle.

  By thus rotating the polishing head 50 about the rotation axis Ct, it is possible to change the angle of the polishing head 50 with respect to the bevel portion of the substrate W. The rotary drive 82 employs a motor capable of precisely controlling the position and speed of a servomotor, stepping motor or the like, and the polishing head 50 is configured to be rotatable at a desired speed to a desired programmed angle. There is.

  FIG. 8 is a schematic view showing a state in which the polishing head 50 and the circular motion mechanism 61 are tilted upward by the tilt mechanism 81. FIG. 9 is a diagram in which the polishing head 50 and the circular motion mechanism 61 are tilted downward by the tilt mechanism 81. It is a schematic diagram which shows a state. In FIG. 8, the polishing tape 31 is in contact with the lower region of the bevel portion of the substrate W, and in FIG. 9, the polishing tape 31 is in contact with the upper region of the bevel portion of the substrate W. Thus, by changing the angle of the polishing head 50 along the bevel portion of the substrate W, the entire bevel portion of the substrate W can be polished. When the cross-sectional shape of the bevel portion has a curvature, the angle of the polishing head 50 may be finely changed for polishing, or the rotational speed of the polishing head 50 may be moderated to continuously perform the polishing head 50. It is also possible to change the angle.

  As shown in FIG. 7, the polishing head assembly 49 is connected to the polishing head moving mechanism 105. The polishing head moving mechanism 105 is fixed to the rotary drive 82 of the tilt mechanism 81, and the polishing head 50 is connected to the polishing head moving mechanism 105 via the tilt mechanism 81 and the circular motion mechanism 61. The polishing head moving mechanism 105 is configured to be capable of moving the polishing head assembly 49 in the radial direction of the substrate W. The polishing head moving mechanism 105 can be composed of a linear actuator such as an air cylinder. The polishing head moving mechanism 105 is electrically connected to the operation control unit 180 shown in FIG. 3, and the operation is controlled by the operation control unit 180.

  When the substrate W is transported onto the holding stage 4 of the substrate holding unit 10 and when the substrate W is taken out of the holding stage 4 of the substrate holding unit 10, the polishing head moving mechanism 105 holds the polishing head assembly 49 as a stage. Move in the direction away from 4. When the bevel portion of the substrate W held by the holding stage 4 is polished, the polishing head moving mechanism 105 moves the polishing head assembly 49 toward the substrate W.

  The polishing apparatus of this embodiment comprises one set of polishing head assembly 49 and polishing tool supply and recovery mechanism 41, but in one embodiment two or more sets of polishing head assembly 49 and polishing tool supply A recovery mechanism 41 may be provided. In one embodiment, more than one liquid supply nozzle 28 may be provided.

  Next, the operation of the polishing apparatus of the present embodiment will be described. The operation of the polishing apparatus described below is controlled by an operation control unit 180 shown in FIG. The operation control unit 180 is electrically connected to the substrate holding unit 10, the polishing head assembly 49, and the polishing tool supply and recovery mechanism 41. Operations of the substrate holding unit 10, the liquid supply nozzle 28, the polishing head assembly 49, and the polishing tool supply and recovery mechanism 41 are controlled by the operation control unit 180. The operation control unit 180 is configured of a dedicated computer or a general-purpose computer.

  The substrate W to be polished is held by the holding stage 4 such that the center O1 of the substrate W is positioned on the axial center Cr of the holding stage 4 with the surface (device surface) facing upward by a transport mechanism not shown. Ru. The substrate W is then rotated about the axis Cr of the holding stage 4 (that is, the axis of the substrate W). Next, the liquid is supplied to the surface of the substrate W from the liquid supply nozzle 28. The liquid supplied to the surface of the substrate W spreads over the entire surface of the substrate W by centrifugal force to form a flow of liquid on the bevel portion of the substrate W.

  The polishing tape 31 is supplied to the polishing head 50 in advance. The operation control unit 180 drives the polishing tool supply and recovery mechanism 41 and advances the polishing tape 31 in a direction parallel to the end surface of the pressing mechanism 52 while applying a predetermined tension.

  Then, while the liquid is supplied to the surface of the substrate W, and the polishing tape 31 is brought into contact with the bevel portion of the rotating substrate W, the polishing tool support structure (entire polishing head 50) is moved circularly by the circular motion mechanism 61. The bevel portion of the substrate W is polished. By moving the entire polishing head 50 circularly, the polishing tape 31 is moved relative to the bevel portion of the substrate W. Thus, the polishing tape 31 can be effectively used, the polishing rate can be increased, and clogging of the polishing tape 31 during polishing can be prevented. Furthermore, since the abrasive tape 31 can be used effectively, the usage amount of the abrasive tape 31 can be reduced and the life of the abrasive tape 31 can be improved. In one embodiment, the bevel portion of the substrate W may be polished by circularly moving the entire polishing head 50 while changing the angle of the polishing head 50 with respect to the substrate W by the tilt mechanism 81.

  After a predetermined time has elapsed, the operation control unit 180 stops the operation of the substrate holding unit 10, the polishing head assembly 49, and the polishing tool supply and recovery mechanism 41, and finishes the polishing.

  FIG. 10 is a schematic view showing another embodiment of the polishing apparatus. The configuration and operation of the present embodiment, which is not particularly described, is the same as that of the embodiment described with reference to FIGS. In the present embodiment, the circular motion mechanism 61 is connected to the pressing mechanism 52. More specifically, the pressing pad 52a is fixed to the table 69 (see FIG. 4) of the circular motion mechanism 61 via the holding member 90, and the circular motion mechanism 61 is connected to the air cylinder 52b. The circular motion mechanism 61 is incorporated in the pressing mechanism 52. With such a configuration, the circular motion mechanism 61 can make the pressing pad 52a perform a circular motion (translational rotational motion) while the air cylinder 52b presses the circular motion mechanism 61 and the pressing pad 52a toward the bevel portion of the substrate W. . In the present embodiment, the polishing tool is a polishing tape 31. Further, in the present embodiment, the polishing tool support structure is the pressing mechanism 52, more specifically, the pressing pad 52a.

  In the present embodiment, the circular motion mechanism 61 is a translational rotation mechanism that causes the pressing pad 52a to translate and rotate. The circular movement (translational rotational movement) in the present embodiment is a circular movement (translational rotational movement) in a plane in which the direction of the polishing head 50 is a normal direction. Also in the present embodiment, the polishing tape 31 can be moved relative to the bevel portion of the substrate W by circularly moving the pressing pad 52a.

  In one embodiment, the circular motion mechanism 61 may be coupled to the air cylinder 52b to circularly move the entire pressure mechanism 52, including the pressure pad 52a and the air cylinder 52b. In this case, the polishing tool support structure is the entire pressing mechanism 52.

  FIG. 11 is a schematic view showing still another embodiment of the polishing apparatus. The configuration and operation of the present embodiment, which is not particularly described, is the same as that of the embodiment described with reference to FIGS. The guide rollers 53 a and 53 c of the polishing apparatus shown in FIG. 11 are connected to the circular motion mechanism 61. More specifically, the guide rollers 53a and 53c are fixed to the table 69 (see FIG. 4) of the circular motion mechanism 61 via the holding member 91. Therefore, the guide rollers 53 a and 53 c perform circular motion (translational rotational motion) by the circular motion mechanism 61. That is, the guide rollers 53a and 53c perform the same circular movement in synchronization with the movement of the table 69.

  In the present embodiment, the circular motion mechanism 61 is a translational rotation mechanism that causes the guide rollers 53a and 53c to translate and rotate. The circular movement (translational rotational movement) in the present embodiment is a circular movement (translational rotational movement) in a plane in which the direction of the polishing head 50 is a normal direction. Also in this embodiment, the polishing tape 31 can be moved relative to the bevel portion of the substrate W by circularly moving the guide rollers 53a and 53c. In the present embodiment, the polishing tool is the polishing tape 31, and the polishing tool support structure is the guide rollers 53a and 53c.

  FIG. 12 is a schematic view showing still another embodiment of the polishing apparatus. The configuration and operation of the present embodiment, which is not particularly described, is the same as that of the embodiment described with reference to FIGS. The polishing apparatus shown in FIG. 12 is suitably used for a notch polishing apparatus that polishes a notch which is a peripheral portion of a substrate. As shown in FIG. 12, the polishing apparatus holds a substrate W which is a polishing target, and polishes a notch portion of the substrate W held by the substrate holding portion 110 and the substrate W held by the substrate holding portion 110. The polishing head assembly 149 removes foreign substances and flaws from the notch, and the swing mechanism 120 swings the substrate W around the notch in a plane.

  FIG. 12 shows a state in which the substrate holder 110 holds the substrate W. The substrate holder 110 includes a holding stage 114 for holding the substrate W by vacuum suction, a first shaft 115 connected to the central portion of the holding stage 114, and a first end connected to the lower end of the first shaft 115. And a holding stage drive mechanism 117. The first holding stage drive mechanism 117 includes a motor and an air cylinder (not shown) for rotating and moving the holding stage 114 up and down. The first holding stage drive mechanism 117 is configured to be able to rotate the holding stage 114 about its axis Cp and move it vertically along the axis Cp.

  The swing mechanism 120 includes a second shaft 125, a second holding stage drive mechanism 127, and a swing arm 130. The first holding stage drive mechanism 117 of the substrate holding unit 110 is connected to the second shaft 125 by the swing arm 130. That is, one end of the swing arm 130 is fixed to the first holding stage drive mechanism 117, and the other end of the swing arm 130 is fixed to the second shaft 125. The second holding stage drive mechanism 127 includes a motor (not shown). The second shaft 125 and the swing arm 130 are configured to be rotatable about an axial center Cq of the second shaft 125 by the second holding stage drive mechanism 127. The first shaft 115 and the second shaft 125 extend parallel to each other.

  The second holding stage drive mechanism 127 is configured to rotate the second shaft 125 and the swing arm 130 clockwise and counterclockwise by a predetermined angle. When the second holding stage drive mechanism 127 rotates the second shaft 125 and the swing arm 130 clockwise and counterclockwise, the substrate holder 110 also rotates clockwise and counterclockwise by a predetermined angle. The axial center Cp of the first shaft 115 is separated from the axial center Cq of the second shaft 125 by a distance d, and is held by the holding stage 114 on the extension of the axial center Cq of the second shaft 125 The notch of the substrate W is located.

  FIG. 13 is a schematic view of the operation of the substrate W when the swing mechanism 120 is driven, as viewed from above the substrate W. As shown in FIG. 13, when the second holding stage drive mechanism 127 is driven, the substrate W rotates (that is, swings) by a predetermined angle clockwise and counterclockwise around the notch in the plane. Is configured.

  Returning to FIG. 12, the second holding stage drive mechanism 127 further includes an air cylinder (not shown) for moving the second shaft 125, the swing arm 130, and the substrate holding portion 110 up and down. That is, the second holding stage drive mechanism 127 is configured to be able to vertically move the second shaft 125, the swing arm 130, and the substrate holding portion 110 along the axial centers Cq and Cp.

  The substrate W is mounted on the upper surface of the holding stage 114 by a transfer mechanism (not shown) such that the center O1 of the substrate W is on the axial center Cp of the holding stage 114. The substrate W is held on the upper surface of the holding stage 114 with the surface (device surface) facing upward. With such a configuration, the substrate holding unit 110 can rotate the substrate W about the axial center Cp of the holding stage 114 (that is, the axial center of the substrate W), and the second holding stage drive mechanism 127 W can be raised and lowered along the axis Cp of the holding stage 114 together with the substrate holding unit 110.

  The polishing head assembly 149 according to the present embodiment has a polishing head 150 for polishing the notch portion of the substrate W by bringing the polishing tape 160 which is an example of a polishing tool into contact with the notch portion of the substrate W held by the substrate holding portion 110. A circular motion mechanism 61 is provided to circularly move the polishing tool support structure relative to the substrate W. The basic configuration of the polishing head 150 is the same as that of the polishing head 150 shown in FIG. 3, but the polishing head 150 differs from the polishing head 150 in that the pressing mechanism 52 is not provided.

  The configuration and the operation of the circular motion mechanism 61 are the same as the configuration and the operation of the circular motion mechanism 61 shown in FIG. In the present embodiment, the polishing head 150 is fixed to the table 69 (see FIG. 4) of the circular motion mechanism 61 via the holding member 89. Also in this embodiment, the polishing tool support structure is defined as a structure that supports the polishing tool and constitutes at least a part of the polishing head 150. In the present embodiment, the polishing tool is a polishing tape 160, and the polishing tool support structure is the entire polishing head 150. The polishing head 150 faces the peripheral portion of the substrate W when the substrate W is held by the substrate holding unit 110.

  Although the basic configuration of the polishing tape 160 is the same as the configuration of the polishing tape 31 shown in FIGS. 5 and 6, the polishing tape 160 is used in the embodiment shown in FIG. The width is smaller than that of the polishing tape 31. Like the polishing tape 31, the polishing surface of the polishing tape 160 is composed of the surface of the polishing layer having abrasive grains.

  The polishing apparatus according to the present embodiment supplies the partition 190 and the polishing tape 150 to the polishing head 150, and the polishing tool supply and recovery mechanism 141 for recovering from the polishing head 150, and the liquid supply nozzle for supplying liquid to the surface of the substrate W And 128 are further provided. The liquid supply nozzle 128 is connected to the second shaft 125 of the swing mechanism 120 via the holding member 129, and rotates integrally with the holding stage 114 by a predetermined angle around the notch of the substrate W. ing. In the present embodiment, the substrate holder 110, the polishing head assembly 149, the second shaft 125, the swing arm 130, and the liquid supply nozzle 128 are disposed inside the partition 190, and the polishing tool supply and recovery mechanism 141 and the second holding The stage drive mechanism 127 is disposed outside the partition wall 190.

  The polishing tool supply and recovery mechanism 141 includes a supply reel 143 for supplying the polishing tape 160 to the polishing head 150 and a recovery reel 144 for recovering the polishing tape 160 used for polishing the substrate W. A tension motor (not shown) is connected to the supply reel 143 and the recovery reel 144, respectively. Each tension motor can apply a predetermined torque to the supply reel 143 and the recovery reel 144, and can apply a predetermined tension to the polishing tape 160.

  The polishing tape 160 is supplied to the polishing head 150 such that the polishing surface of the polishing tape 160 faces the surface to be polished of the notch portion of the substrate W. The polishing tape 160 is supplied from the supply reel 143 to the polishing head 150 through an opening (not shown) provided in the partition 190, and the used polishing tape 160 is recovered to the recovery reel 144 through the opening.

  The polishing head 150 includes a plurality of guide rollers 153 a, 153 b, 153 c, 153 d, 153 e, 153 f for supporting the polishing tape 160. The polishing tool supply and recovery mechanism 141 further includes a plurality of guide rollers 153 g and 153 h for supporting the polishing tape 160. The advancing direction of the polishing tape 160 is guided by guide rollers 153a, 153b, 153c, 153d, 153e, 153f, 153g, 153h. In particular, guide rollers 153a and 153c disposed at the tip of the polishing head 150 guide the polishing tape 160 so that the polishing tape 160 advances in a direction parallel to the polishing surface of the notch portion of the substrate W. The polishing head 150 polishes the notch of the substrate W by bringing the polishing tape 160 extending between the guide rollers 153 a and 153 c into contact with the notch of the substrate W.

  The liquid supply nozzle 128 is disposed outside the holding stage 114. The liquid supply nozzle 128 is connected to a liquid supply not shown. The liquid supply nozzle 128 is disposed facing the center O1 of the substrate W. The liquid is supplied from the liquid supply nozzle 128 to the surface of the substrate W to form a flow of liquid on the notch of the substrate W. The notches of the substrate W are polished in the presence of liquid. The liquid flows downward from the peripheral portion of the substrate W, whereby polishing debris can be removed from the notch of the substrate W. Further, the above-described liquid prevents the liquid including polishing debris and foreign matter generated by the polishing of the substrate W from adhering to the surface of the substrate W. As a result, the surface of the substrate W can be kept clean. In the present embodiment, pure water or alkaline water is used as the above-mentioned liquid.

  As shown in FIG. 13, the polishing head assembly 149 further includes a tilt mechanism 81. The configuration and operation of the tilt mechanism 81 are the same as those of the tilt mechanism 81 shown in FIG.

  FIG. 14 is a schematic view showing a state in which the polishing head 150 and the circular motion mechanism 61 are inclined upward by the tilt mechanism 81. FIG. 15 is a diagram in which the polishing head 150 and the circular motion mechanism 61 are inclined downward by the tilt mechanism 81. It is a schematic diagram which shows a state. In the embodiment shown in FIG. 14, the polishing tape 160 is in contact with the lower region of the notch of the substrate W, and in the embodiment shown in FIG. 15, the polishing tape 160 is in the upper region of the notch of the substrate W. It is in contact. Thus, by changing the angle of the polishing head 150 along the notch of the substrate W, the entire notch of the substrate W can be polished. If the cross-sectional shape of the notch has a curvature, the angle of the polishing head 150 may be finely changed for polishing, or the rotational speed of the polishing head 150 may be moderated to continuously perform the polishing head 150. It is also possible to change the angle.

  As shown in FIG. 13, the polishing head assembly 149 is connected to the polishing head moving mechanism 155. The polishing head moving mechanism 155 is fixed to the rotary drive 82 of the tilt mechanism 81, and the polishing head 150 is connected to the polishing head moving mechanism 155 via the tilt mechanism 81 and the circular motion mechanism 61. The polishing head moving mechanism 155 is configured to be able to move the polishing head assembly 149 in the radial direction of the substrate W. The polishing head moving mechanism 155 can be composed of a linear actuator such as an air cylinder. The polishing head moving mechanism 155 is electrically connected to the operation control unit 180 shown in FIG. 12, and the operation is controlled by the operation control unit 180.

  When the substrate W is conveyed onto the holding stage 114 of the substrate holding unit 110 and when the substrate W is taken out of the holding stage 114 of the substrate holding unit 110, the polishing head moving mechanism 155 holds the polishing head assembly 149. Move in the direction away from 114. When the notch portion of the substrate W held on the holding stage 114 is polished, the polishing head moving mechanism 155 moves the polishing head assembly 149 toward the substrate W until the polishing tape 160 contacts the notch portion. .

  The polishing apparatus of this embodiment comprises one set of polishing head assembly 149 and polishing tool supply and recovery mechanism 141, but in one embodiment, two or more sets of polishing head assembly 149 and polishing tool supply A recovery mechanism 141 may be provided. Further, in one embodiment, two or more liquid supply nozzles 128 may be provided.

  Next, the operation of the polishing apparatus of the present embodiment will be described. The operation of the polishing apparatus described below is controlled by an operation control unit 180 shown in FIG. The operation control unit 180 is electrically connected to the substrate holding unit 110, the swing mechanism 120, the polishing head assembly 149, and the polishing tool supply and recovery mechanism 141. Operations of the substrate holding unit 110, the swing mechanism 120, the liquid supply nozzle 128, the polishing head assembly 149, and the polishing tool supply and recovery mechanism 141 are controlled by the operation control unit 180. The operation control unit 180 is configured of a dedicated computer or a general-purpose computer.

  The substrate W to be polished is held by the holding stage 114 such that the surface (device surface) is upward and the center O1 of the substrate W is at the axial center Cp of the holding stage 114 by a transport mechanism (not shown). A notch search unit (not shown) for detecting the notch portion of the substrate W held by the holding stage 114 is provided inside the partition wall 190. The notch search unit is configured to move between the notch search position and the retracted position by an actuator (not shown). When the notch is detected by the notch search unit, the holding stage 114 is rotated by the first holding stage drive mechanism 117 until the notch faces the polishing head 150. Furthermore, the liquid is supplied to the surface of the substrate W from the liquid supply nozzle 128. The liquid supply nozzle 128 continuously supplies the liquid while the substrate W is being polished.

  The polishing tape 160 is supplied to the polishing head 150 in advance. The polishing head moving mechanism 155 (see FIG. 13) moves the polishing head 150 toward the substrate W until the polishing tape 160 contacts the notch. The operation control unit 180 drives the polishing tool supply and recovery mechanism 141 to advance the polishing tape 160 in a direction parallel to the polishing surface of the notch portion of the substrate W while applying a predetermined tension.

  Then, the swing mechanism 120 is driven to rotate (swing) the substrate W clockwise or counterclockwise around a notch in a plane by a predetermined angle. While the polishing tape 160 is in contact with the notch portion of the substrate W, the circular motion mechanism 61 circularly moves the polishing tool support structure (the entire polishing head 150) to polish the notch portion of the substrate W. By circularly moving the entire polishing head 150, the polishing tape 160 can be moved relative to the notch portion of the substrate W. In one embodiment, while the angle of the polishing head 150 is changed by the tilt mechanism 81, the notch portion of the substrate W may be polished by circular movement of the entire polishing head 150.

  After a predetermined time has elapsed, the operation control unit 180 stops the operations of the swing mechanism 120, the polishing head assembly 149, and the polishing tool supply and recovery mechanism 141, and finishes the polishing.

  FIG. 16 is a schematic view showing still another embodiment of the polishing apparatus. The configuration and operation of the present embodiment, which is not particularly described, is the same as that of the embodiment described with reference to FIGS. Polishing device guide rollers 153 a and 153 c shown in FIG. 16 are connected to a circular motion mechanism 61. More specifically, the guide rollers 153a and 153c are fixed to the table 69 (see FIG. 4) of the circular motion mechanism 61 via the holding member 191. Also in the present embodiment, the polishing tape 160 can be moved relative to the notch portion of the substrate W by circularly moving the guide rollers 153a and 153c. In the present embodiment, the polishing tool is the polishing tape 160, and the polishing tool support structure is the guide rollers 153a and 153c.

  The embodiments described above are described for the purpose of enabling one skilled in the art to which the present invention belongs to to practice the present invention. Various modifications of the above-described embodiment can naturally be made by those skilled in the art, and the technical idea of the present invention can be applied to other embodiments. Accordingly, the present invention is not limited to the described embodiments, but is to be construed in the broadest scope in accordance with the technical concept defined by the claims.

4 holding stage 5 shaft 7 holding stage drive mechanism 10 substrate holding unit 28 liquid supply nozzle 31 polishing tape 33 base tape 35 polishing layer 37 abrasive grain 39 binder 40 elastic layer 41 polishing tool supply and recovery mechanism 43 supply reel 44 recovery reel 49 polishing Head assembly 50 Polishing head 52 Pressing mechanism 52a Pressing pad 52b Air cylinder 53a to 53h Guide roller 61 Circular motion mechanism 62 Motor 63 Rotation shaft 63a Shaft 65 Eccentric rotator 65a Shaft 67 Bearing 69 Table 70 Crank 71 Crank base 72 1 axis body 72a axis 73 second axis 73a axis 75 bearing 77 bearing 79 support member 81 support member 81 tilt mechanism 82 rotation drive device 85 crank arm 89 holding member 90 holding member 91 holding member 91 partition member 105 partition 105 polishing head moving mechanism 110 substrate holding Part 114 Holding stage 15 first shaft 117 first holding stage drive mechanism 120 swing mechanism 125 second shaft 127 second holding stage drive mechanism 128 liquid supply nozzle 129 holding member 130 swing arm 141 polishing tool supply and recovery mechanism 143 supply reel 144 recovery Reel 149 Polishing head assembly 150 Polishing head 153a to 153h Guide roller 155 Polishing head moving mechanism 160 Polishing tape 180 Operation control unit 191 Holding member

Claims (12)

A method of polishing the periphery of a substrate, comprising
The substrate holder holds the substrate,
Polishing characterized in that the polishing tool supporting structure constituting at least a part of the polishing head is circularly moved to polish the peripheral portion of the substrate while bringing the polishing tool into contact with the peripheral portion of the substrate by the polishing head. Method.   The polishing method according to claim 1, wherein the circular motion is translational rotational motion.   The polishing method according to claim 1, wherein a peripheral portion of the substrate is a bevel portion of the substrate.   The polishing method according to claim 1, wherein a peripheral portion of the substrate is a notch of the substrate.   The polishing method according to any one of claims 1 to 4, wherein the polishing tool support structure is the entire polishing head. The polishing head has a pressing mechanism for pressing the polishing tool against the peripheral portion of the substrate,
The polishing method according to any one of claims 1 to 3, wherein the polishing tool support structure is the pressing mechanism. The polishing tool is a polishing tape having abrasive grains on the surface,
The polishing method according to any one of claims 1 to 4, wherein the polishing tool support structure is a plurality of guide rollers for supporting the polishing tape. A substrate holding unit for holding a substrate;
A polishing head for bringing a polishing tool into contact with the peripheral portion of the substrate;
What is claimed is: 1. A polishing apparatus comprising: a circular motion mechanism configured to circularly move a polishing tool support structure that constitutes at least a part of the polishing head.   The polishing apparatus according to claim 8, wherein the circular motion mechanism is a translational rotation mechanism that translates and rotates the polishing tool support structure. The circular motion mechanism is coupled to the polishing head,
The polishing apparatus according to claim 8, wherein the polishing tool support structure is the entire polishing head. The polishing head has a pressing mechanism for pressing the polishing tool against the peripheral portion of the substrate,
The polishing apparatus according to claim 8, wherein the polishing tool support structure is the pressing mechanism. The polishing tool is a polishing tape having abrasive grains on the surface,
The circular motion mechanism is connected to a plurality of guide rollers supporting the polishing tape,
The polishing apparatus according to claim 8, wherein the polishing tool support structure is the plurality of guide rollers.

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