JP2013082073A - Polishing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently transmit rotation by uniforming a contact state of rollers with the peripheral surface of a carrier surface plate, in a polishing system rotating the carrier surface plate through the rollers.SOLUTION: The carrier surface plate 40 is rotated by a plurality of roller drive units 100 which include roller drive motors 115 for rotatively driving the rollers 110 and roller movement structures 150 for radially moving the rollers, and which are arranged around the carrier surface plate 40. The polishing system includes a radial position detection section 160 that detects the position of the outer peripheral surface 45 of the surface plate passing through an area with the roller drive units 100 arranged when the carrier surface plate 40 is rotated, and is configured such that a control device controls the movement position and rotational speed of the rollers 110 of the roller drive units according to the position of the outer peripheral surface 45 detected by the radial position detection section 160.

Description

The present invention relates to a polishing system that polishes a substrate flatly. More specifically, the present invention relates to a carrier that has a substrate container for holding a substrate and is disposed between upper and lower surface plates, and more than the upper and lower surface plates. The present invention relates to a polishing system equipped with a carrier surface plate formed in a large-diameter annular shape and a carrier surface plate driving mechanism for rotating a carrier sandwiched between upper and lower surface plates by rotating the carrier surface plate.

Equipped with an upper surface plate, a lower surface plate, a carrier having a substrate holding part for holding the substrate, disposed between the upper and lower surface plates, and a carrier driving mechanism for rotating the carrier sandwiched between the upper and lower surface plates As a polishing system, polishing apparatuses such as a double-sided lapping apparatus and a double-side CMP apparatus that polish the upper and lower surfaces of a substrate flatly are widely known. The carrier driving mechanism of such a polishing apparatus is generally formed on the outer periphery of the sun gear that protrudes upward through the center of the lower surface plate, the internal gear that surrounds the outer surface of the lower surface plate, and the carrier. And a planetary gear that meshes with the sun gear and the internal gear, and a sun gear drive structure that rotationally drives the sun gear around a central axis extending vertically. Then, hold the substrate to be polished in the substrate receiving portion of the carrier and sandwich it between the upper and lower surface plates, rotate the upper and lower surface plates while supplying the polishing liquid, and rotate the sun gear to rotate the upper and lower surface plates. The carrier is moved in a planetary motion between the two, whereby the upper and lower surfaces of the substrate are polished flatly (see, for example, Patent Document 1 and Patent Document 2).

JP 2003-31608 A JP2007-301650A

However, in the conventional polishing apparatus as described above, the sun gear is disposed so as to protrude upward in the center of the lower surface plate, so that the substrate size that can be polished is limited to half or less of the surface plate diameter. In recent years, along with the increase in size of liquid crystal display devices, there has been a need for a polishing system that flatly polishes a large glass substrate on both sides. However, if the conventional polishing device as described above is increased in size as it is, the entire device becomes enormous. End up. Therefore, a carrier surface plate having an annular shape with a larger diameter than the upper and lower surface plates and having a carrier connected to the inner periphery and supported so as to be rotatable about a virtual center axis extending vertically, and a carrier that rotationally drives the carrier surface plate. A polishing system equipped with a surface plate drive mechanism has been intensively studied.

In the polishing system provided with the carrier surface plate as described above, the carrier surface plate has a hollow annular shape, so that an axis cannot be provided at the center of rotation. Therefore, the carrier surface plate drive mechanism includes a plurality of roller drive units around the carrier surface plate, each having a roller in contact with the peripheral surface (outer peripheral surface or inner peripheral surface) of the carrier surface plate and a roller drive motor that rotationally drives the roller. The carrier platen is configured to rotate via each roller by synchronously rotating the roller drive motor of each unit. The carrier surface plate of such a polishing system has a diameter of about 3 m or more and is difficult to be formed by turning or the like. For example, a steel material cut into a strip-like shape is formed into an arc shape by a bending roll or the like. It is formed by molding and welding annular members up and down. For this reason, the circumferential surface that the roller contacts does not have a clean circular shape, and a situation occurs in which the circumferential surface greatly shakes in the radial direction when the carrier surface plate is rotated.

As a result, there is a problem that smooth rotation transmission is difficult, for example, when the roller is separated from the peripheral surface due to the finish of the carrier surface plate and the rotational driving force is not transmitted or an excessive load is generated on the roller. In addition, when the rotational speed (rad / sec) of the carrier surface plate is constant, the peripheral speed (linear speed m / sec) differs on the peripheral surface at different radial positions from the center of rotation. For each unit, there is a difference between the rotation speed of the roller and the peripheral speed of the peripheral surface with which the roller comes into contact, and there is a problem that it is difficult to make the contact state uniform and efficiently transmit the rotation.

The present invention has been made in view of such a problem, and provides a polishing system that makes it possible to efficiently transmit rotation by making the contact state between the roller of the roller driving unit and the peripheral surface of the carrier surface plate uniform. For the purpose.

In order to achieve the above object, the polishing system of the present invention has a disk-shaped upper and lower surface plates provided facing each other in the vertical direction, a substrate container for holding the substrate, and an upper surface plate and a lower surface plate. A carrier surface plate, a carrier surface plate formed in an annular shape having a larger diameter than the upper surface plate and the lower surface plate, the carrier surface being connected to the inner periphery, and an upper surface plate by rotating the carrier surface plate A carrier surface plate driving mechanism for rotating the carrier held between the lower surface plate and the lower surface plate is provided. The carrier surface plate driving mechanism includes a roller whose outer peripheral surface is in contact with the peripheral surface of the carrier surface plate and is supported so as to be rotatable about a roller shaft extending vertically, a roller drive motor for rotating the roller, and a roller for the carrier surface plate. It has a roller moving structure that moves in the radial direction, and comprises a plurality of roller drive units that rotate the carrier surface plate by rotating the rollers by a roller drive motor. In this polishing system, radial position detection means for detecting the radial position of the peripheral surface of the carrier surface plate that passes through the roller arrangement area in each roller drive unit (for example, the radial position detection unit 160 in the embodiment, 160 ′) and a control device for controlling the roller movement position by the roller movement structure of each roller drive unit and the rotation speed of the roller by the roller drive motor, and the control device detects the circumference detected by the radial position detection means. In accordance with the radial position of the surface, the moving position and rotational speed of the roller in each roller drive unit are controlled so that the contact state between the peripheral surface of the carrier surface plate and the roller of each roller drive unit is constant. Composed.

The radial position detection means (for example, the radial position detection unit 160 in the embodiment)
Consists of a memory in which the shape of the peripheral surface of the carrier surface plate is set and stored in advance, and an angular position detection device for detecting the rotational angle position of the carrier surface plate, and the shape and angular position of the peripheral surface set and stored in the memory It is preferable that the radial position of the circumferential surface passing through the roller arrangement region in the roller drive unit is detected based on the rotation angle position of the carrier surface plate detected by the detection device.

Alternatively, the radial position detector (for example, the radial position detector 16 in the embodiment)
0 ′) comprises a peripheral surface displacement detection device that detects the displacement state of the peripheral surface that is displaced in accordance with the rotation of the carrier surface plate, and based on the displacement state of the peripheral surface detected by the peripheral surface displacement detection device, It is preferable to configure so as to detect the radial position of the circumferential surface passing through the roller arrangement region in the roller drive unit.

Each of the roller drive units includes a roller arm provided with a roller, a slide block that supports the roller arm so as to be movable in the radial direction of the carrier surface plate, and is moved in the radial direction of the carrier surface plate by a roller moving structure. It is preferable that a spring is provided between the roller arm and the slide block to bias the roller to the circumferential surface, and the roller is pressed against the circumferential surface with a substantially constant biasing force.

The polishing system of the present invention includes a radial position detection means for detecting the radial position of the peripheral surface of the carrier surface plate, and a control device for controlling the moving position and the rotational speed of the roller in each roller driving unit. However, according to the radial position of the peripheral surface detected by the radial position detecting means, the moving position and the rotational speed of the rollers of each roller drive unit are controlled so that the contact state of the rollers of each roller drive unit is constant. Is done. According to such a configuration, even if there is a radial runout on the peripheral surface of the carrier surface plate, the position and rotational speed of the rollers of each roller drive unit are controlled according to this radial runout. A contact state between the peripheral surface of the surface plate and the roller can be made uniform, and a polishing system capable of efficiently transmitting rotation can be provided.

It is the outline | summary block diagram which looked at the roller drive unit of the grinding | polishing system to which this invention is applied from the side. It is a conceptual diagram of the state which looked at the grinding | polishing system to which this invention is applied from the side. It is the top view seen in the III-III arrow direction in FIG. It is a block diagram which mainly shows the radial direction position detection part of the grinding | polishing system of a 1st structure form. It is the schematic diagram which looked at the carrier surface plate of the grinding | polishing system of a 1st structure form from upper direction. It is explanatory drawing which shows the arrangement | positioning state of a some rotation detection sensor. It is a block diagram which mainly shows the radial direction position detection part of the grinding | polishing system of a 2nd structure form. It is the schematic diagram which looked at the carrier surface plate of the grinding | polishing system of a 2nd structure form from upper direction. It is a schematic diagram of the displacement waveform of the outer peripheral surface detected in a peripheral surface position detection sensor.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. FIG. 2 is a conceptual diagram of the polishing system 1 to which the present invention is applied as viewed from the side, and FIG. 3 is a plan view of the polishing system 1 as viewed in the direction of arrows III-III in FIG. The overall configuration will be described. For convenience of explanation, FIG. 2 shows the carrier and the carrier surface plate in a sectional view.

The polishing system 1 has a disk-shaped upper surface plate 10 and lower surface plate 20 that are provided facing each other in the vertical direction, and a substrate container that holds the substrate W, and is disposed between the upper surface plate 10 and the lower surface plate 20. Career 3
The upper surface plate 10 and the lower surface plate are rotated by rotating the carrier surface plate 40 and the carrier surface plate 40 which are formed in an annular shape larger in diameter than the upper and lower surface plates 10 and 20 and to which the carrier 30 is connected. 2
The carrier platen driving mechanism 50 that rotates the carrier 30 sandwiched between 0 and 0, and the controller 80 that controls the operation of the polishing system 1 are provided.

The upper surface plate 10 and the lower surface plate 20 have a large and approximately the same diameter disk shape with a diameter of about 2 to 4 [m],
An upper surface plate rotating shaft 12 extending upward is fixed to the upper surface center of the upper surface plate 10, and a lower surface plate rotating shaft 22 extending downward is fixed to the lower surface center of the lower surface plate 20. The upper surface plate rotating shaft 12 has an upper surface plate driving mechanism 15,
A lower surface plate driving mechanism 25 is connected to the lower surface plate rotation shaft 22, and the upper and lower surface plates are respectively connected to each rotation 12.
Each of the 22 axes is configured to be independently rotatable in a horizontal plane. The lower surface of the upper surface plate 10,
The upper surface of the lower surface plate 20 is processed to have a high flatness, and grooves for supplying the processing liquid to each part are formed in a lattice shape to form the polished surfaces 11 and 21. When performing double-side CMP processing with the polishing system 1, for example, a polishing pad made of polyurethane containing fine closed-cell foamed cells is attached to form a polishing surface.

The upper surface plate 10 can be moved to an opposed position facing the lower surface plate 20 and a retreat position retracted from the upper side of the lower surface plate 20 to the side by an upper surface plate moving mechanism (not shown), and can be moved up and down at the opposed position. And a pressurizing structure that pressurizes the substrate W in a state where the substrate W is sandwiched between the upper and lower polishing surfaces 11, 21, and the substrate is subjected to an arbitrary polishing pressure set in the control device 80. Both sides of W are configured to be polished.

The carrier 30 has a disk shape that is somewhat thinner than the thickness of the substrate W, and a substrate accommodating portion 31 that holds the substrate W is formed in the disk so as to penetrate vertically. The substrate housing portion is formed in a frame shape slightly larger than the outer dimensions of the substrate W to be polished, and the substrate W is mounted on the substrate housing portion 31 of the carrier 30 supported on the upper surface of the lower surface plate 20. Thus, the outer peripheral end surface of the substrate W is held in the substrate accommodating portion 31.

The carrier surface plate 40 has an annular shape larger in diameter than the upper surface plate 10 and the lower surface plate 20, for example,
It is formed in an annular shape with a diameter of about 3 to 5 [m] and a width and height of the annular portion of about 150 to 200 [mm]. The carrier surface plate 40 is supported by a plurality of cylindrical rollers 42 provided on the outer peripheral side of the lower surface plate 20, and is rotatably disposed on the outer peripheral side of the upper and lower surface plates. . A carrier engaging portion that engages with the outer peripheral portion of the carrier 30 and transmits rotational torque is formed on the inner peripheral side of the carrier surface plate 40, and the carrier 30 is connected to the carrier 30 connected via the carrier engaging portion. The rotational torque of the surface plate 40 is transmitted.

The carrier surface plate drive mechanism 50 includes a plurality of roller drive units (four roller drive units in the illustrated configuration example) 100 provided on the outer periphery of the carrier surface plate 40. By rotating the surface plate 40, the carrier 30 is rotated through the carrier engaging portion. The carrier surface plate driving mechanism 50 will be described in detail later. Each roller driving unit 100 includes a roller 110 that contacts the outer peripheral surface 45 of the carrier surface plate 40 and a roller driving motor 115 that rotationally drives the roller 110. ,
The control device 80 controls the rotation of the roller driving motor 115 to rotate the carrier surface plate 40 clockwise or counterclockwise in plan view via the roller 110. The plurality of roller driving mechanisms 100, 100... Of the carrier surface plate rotating mechanism 50 are fixed to the base frame 151 of the carrier surface plate rotating mechanism 50, and the entire carrier surface plate rotating mechanism 50 is the upper and lower surface plates 1.
It is configured to swing relative to the rotation centers of 0 and 20.

When polishing the substrate W in the polishing system 1, first, the upper surface plate 10 is changed to the lower surface plate 20.
The substrate W is loaded from above, accommodated in the substrate accommodating portion 31 of the carrier 30 and supported by the lower surface plate 20. Next, the upper surface plate 10 is set at a facing position above the lower surface plate 20 and moved downward to sandwich the substrate W between the polishing surfaces 11 and 21 of the upper and lower surface plates. Then, the upper and lower surface plates 10 and 20 are rotated in the reverse direction or the same direction by the upper surface plate driving mechanism 15 and the lower surface plate driving mechanism 25 while supplying the processing liquid to the polishing processing unit, and a predetermined processing pressure is applied by the pressure structure. In the state set to, the carrier 30 is rotated by the carrier surface plate driving mechanism 50. As a result, the upper and lower surfaces of the substrate W are simultaneously polished with the set processing pressure.

In the polishing system 1 configured as described above, the carrier surface plate 40 is a large-diameter and hollow annular shape as described above, and therefore, this is cut out from an integral member and formed by turning or the like. Is difficult from the viewpoints of production cost and material weight. Therefore, in general, a pair of upper and lower circular members are formed by joining plate-shaped arc members divided into a plurality of rings by welding, bolt fastening, etc., and matched to the height of the carrier surface plate. A strip-shaped member is formed into an arc shape in accordance with the curvature of the outer peripheral surface by a bending roll or a press brake to form a plurality of peripheral members, and the peripheral members are joined to the outer periphery of the upper and lower annular members, etc. By means, it is formed into an integral annular shape.

From such a configuration, the profile (contour shape) of the outer peripheral surface 45 of the carrier surface plate 40 is
Although it is circular as a whole, it is a shape with irregularities with waviness, and the radial distance from the virtual center to the outer peripheral surface 45 when the contour shape is approximated to a circle varies depending on the angular position in the circumferential direction (FIG. 5). See). This means that when the carrier surface plate 40 is rotated, the outer peripheral surface 45 passing through the roller position is displaced in the radial direction. According to the inventors' research, the outer diameter is φ3.
. When a plurality of the 5 m carrier surface plates were measured, it was confirmed that the outer peripheral surface 45 was shaken in the radial direction by about 5 to 15 mm (hereinafter referred to as “surface runout”).

As a result, the roller 110 is attached to the tip of a swing arm that is swingably displaceable in the radial direction of the carrier surface plate 40, and the roller 110 is biased in the inner diameter direction of the carrier surface plate by a spring, so that the roller 110 is fixed to the carrier surface. When configured to elastically contact the outer peripheral surface of the board and the surface runout of the outer peripheral surface 45 of the carrier surface plate is larger than the swing range of the swing arm, the roller 110 rotates away from the outer peripheral surface 45. There is a case where the driving force is not transmitted or an excessive force is applied to the roller and the swing arm. Further, if the swinging range of the swinging arm is expanded, the elastic contact between the outer peripheral surface 45 of the carrier surface plate and the roller 110 can be maintained, but the change in the position of the swinging arm has a pressing force proportional to this. As a result, the load resistance changes and smooth rotation transmission is difficult.

Further, when the rotation speed ω [rad / sec] of the carrier surface plate 40 is constant, the linear velocity of the outer peripheral surface at different radial distances from the rotation center, that is, the circumferential speed v [mm / sec] is different. . For this reason, when the roller drive motor is controlled at the same rotational speed for the plurality of roller drive units 100, the peripheral speed of the outer peripheral surface of the roller 110 and the peripheral speed of the outer peripheral surface of the roller position where the roller contacts each unit. There is a difference, and in some roller drive units, the roller acts in the braking direction at the contact part, and in other units the roller acts in the acceleration direction. This also makes the contact state uniform and efficient rotation transmission Is difficult.

The polishing system 1 includes a radial position detection unit 160 that detects the radial position of the outer peripheral surface 45 of the carrier surface plate that passes through the roller position of each roller drive unit 100, and each roller drive unit 100 includes a roller 110 as a carrier. A roller moving structure 150 for moving in the radial direction of the surface plate 40 is provided, and the control device 80 determines the outer peripheral surface 45 of the carrier surface plate and each roller drive unit according to the radial position detected by the radial position detecting unit 160. The roller moving position by the roller moving structure 150 and the rotation speed of the roller by the roller driving motor 115 are controlled so that the contact state with the roller 110 becomes constant.

As shown in FIG. 1, the roller drive unit 100 includes a roller 1
A roller arm 120 and a roller arm 12 which rotatably support the roller 10 around the roller shaft 112
A roller driving motor 115 that rotates and drives the roller 110 via a speed reducer, a slide block 130 that supports the roller arm 120 movably in the radial direction of the carrier surface plate 40 via a slide guide 125, and the roller arm 120. And a spring 127 that is interposed between the slide block 130 and urges the roller arm 120 toward the inner diameter of the carrier surface plate 40.
Roller moving structure 150 for moving the slide block 130 in the radial direction of the carrier surface plate 40
And so on.

The roller moving structure 150 includes a base frame 15 that is a common base for each roller driving unit.
1 and a slide guide 152 that is provided between the base frame 151 and the slide block 130 and slidably supports the slide block 130 in the radial direction of the carrier surface plate 40.
A ball screw 154 extending in the radial direction of the carrier base plate 40 and rotatably supported, and a roller moving motor 1 coupled to the shaft end of the ball screw 154 to drive the ball screw 154 to rotate.
55, a ball nut 1 provided on the slide block 130 and screwed into the ball screw 154
A nut flange 136 and the like 56 are coupled to each other.

The controller 80 controls the roller moving motor 155 and the roller driving motor 11 in the roller moving structure 150 according to the radial position of the outer peripheral surface 45 detected by the radial position detector.
5 controls the rotation speed of the roller 110.

In the polishing system 1 of the first configuration form, the radial position detection unit 160 detects the rotational angle position of the memory 81 in which the shape of the outer peripheral surface 45 of the carrier surface plate is preset and stored, and the carrier surface plate 40. The roller 100 in each roller drive unit 100 based on the shape of the outer peripheral surface set and stored in the memory 81 and the rotational angle position of the carrier surface plate 40 detected by the angular position detector 161. It is comprised so that the radial direction position of the outer peripheral surface which passes the arrangement | positioning area | region may be detected. The polishing system 1 will be described with reference to the block diagram shown in FIG.

The contour shape (profile) of the outer peripheral surface 45 of the carrier surface plate is measured in advance, and the control device 80
The setting is stored in the memory 81. Specifically, as shown in FIG. 5 which is a schematic diagram when the carrier surface plate 40 is viewed from above, the profile Pf of the outer peripheral surface 45 measured in advance is approximated to a circle C by a known image processing method, and is virtually calculated. The center O and the radius R are obtained, a coordinate system passing through the virtual center O and a reference angle posture is set, and an arbitrary position P on the outer peripheral surface is set to a radial distance r from the virtual center O and a circumferential angle θ. The profile Pf defined as P (r, θ) is set and stored in the memory 81.

On the other hand, the angular position detection device 161 includes a reference position detection sensor 162 for detecting a reference angular position of the carrier surface plate 40 set corresponding to the coordinate system, and a rotation detection sensor for detecting the rotation speed of the carrier surface plate 40. 165, and the CP of the control device 80 from these detection signals.
A U (arithmetic processing unit) 82 is configured to calculate the angular orientation of the carrier surface plate 40.

The reference position detection sensor 162 detects the reference angle position of the carrier surface plate 40 by detecting the reference member set on the carrier surface plate 40 while the carrier surface plate 40 is rotating. For example,
As shown in FIG. 5, while the shield plate 163 is erected on the upper surface of the carrier surface plate 40, the shield plate 1
A reference position detection sensor 162 in the form of a photo interrupter comprising a light projecting portion 162a and a light receiving portion 162b is provided on the inner peripheral side and the outer peripheral side of the passing position of 63, and the passing timing of the shielding plate 163 accompanying the rotation of the carrier surface plate 40 is detected. By doing so, the reference rotation position (for example, θ = 0 degree) of the carrier surface plate 40 is detected.

On the other hand, the rotation detection sensor 165 is a sensor for detecting the actual rotation speed of the rotating carrier surface plate 40, and is detected to be fixed to the carrier surface plate 40 at a predetermined angular pitch centered on the virtual center O. The body 166 is detected. As the carrier surface plate 40 rotates, the rotation detection sensor 16
5 is a pulse-like signal having a frequency proportional to the rotation speed of the carrier surface plate 40, and the number of pulses per unit time of the detection signal is counted to determine the rotation speed ω of the carrier surface plate 40. [rad / sec] can be calculated. For example, the magnet (detected body) 166 is fixed to the outer peripheral surface 45 of the carrier surface plate at a pitch of 5 degrees around the virtual center O,
When detected by the rotation detection sensor 165 in the form of a magnetic sensor, 72 pulses are detected when the carrier surface plate 40 rotates 360 degrees. Therefore, if 12 pulses are detected per second, the rotational speed ω of the carrier surface plate 40 at that time is calculated as 10 [rpm] = π / 3 [rad / sec].

Then, from the reference angle position of the carrier surface plate 40 detected by the reference position detection sensor 162 and the rotation speed ω of the carrier surface plate 40 detected based on the detection signal of the rotation detection sensor 165 at an arbitrary time. The angular orientation of the carrier surface plate 40 can be detected, and the roller driving unit 100 (100A, 100B, 100C, 100D) is rotated by rotating the profile Pf of the outer peripheral surface 45 set and stored in the memory 81 to the angular orientation. ) In the radial direction of the outer peripheral surface 45 where the roller 110 should be located. For example, from the position P _A (r _A , θ _A ) of the outer peripheral surface 45 passing through the roller position of the roller drive unit 100A, the radial position where the roller 110 of the roller drive unit 100A should be located is obtained.

The control device 80 controls the rotation speed of the roller 110 by the roller movement motor 155 and the roller drive motor 115 in the roller movement structure 150 according to the radial position and the rotation speed thus obtained. For example, for the roller drive unit 100A in which the outer peripheral surface 45 of the carrier surface plate swings δ _A outside the approximate circle C when the radial position of the approximate circle C is used as a reference for the roller movement position and the roller rotation speed, _A roller moving motor 155 so that the slide block 130 moves δ _{A in the} direction of the outer diameter of the carrier surface plate 40 according to the change of the radial position.
And the roller 110 biased by the spring 127 is controlled to be pressed against the outer peripheral surface 45 of the carrier surface plate with a predetermined contact pressure. Further, the peripheral speed of the outer peripheral surface of the roller 110, to control the rotational speed of the roller drive motor 115 to match the peripheral speed of the outer peripheral surface of the radial position r _A.

Similarly, the outer peripheral surface 45 is about [delta] _C swings roller drive unit 100C to the inside of the approximate circle C of the carrier plate, the slide block 130 radially inward of the carrier plate 40 in response to a change in radial position of the outer peripheral surface 45 [delta] _C to control the rotation of the roller movement motor 155 to move,
Control is performed so that the roller 110 of the roller drive unit 100C is pressed against the outer peripheral surface 45 of the carrier surface plate with the same contact pressure as the roller of the roller drive unit 100A. Further, the rotational speed of the roller drive motor 115 is controlled so that the peripheral speed of the outer peripheral surface of the roller 110 matches the peripheral speed of the outer peripheral surface of the radial position r _C.

That is, the control device 80 controls the speed of the entire roller driving unit based on the rotational speed ω [rad / sec] of the carrier surface plate 40 detected by the detection signal of the rotation detection sensor 165, and uses the radial position detector. The movement position and rotational speed of each roller 110 of each roller drive unit are controlled according to the difference δ _A , δ _C, etc. between the detected approximate circle C and the radial position of each roller drive unit.

For this reason, the carrier surface plate 40 is driven to rotate at a constant rotational speed ω around an axis about a virtual rotation axis that extends vertically through the virtual center O of the approximate circle C. At this time, in each roller drive unit 100 (100A, 100B, 100C, 100D), each roller 110
Is always pressed against the outer peripheral surface 45 of the carrier surface plate with a constant contact pressure, and the rotational driving force is transmitted in a state where all the rollers have no speed difference from the outer peripheral surface of the carrier surface plate. Therefore, stable and efficient rotation transmission is possible without causing uneven wear of each roller or energy loss due to a difference in peripheral speed. Further, since the carrier 30 and the carrier surface plate 40 are smoothly rotated around the virtual center axis, the rotation axis of the substrate W held by the carrier 30 does not shake or discontinuously move, As a result, the polishing process can be stabilized and the polishing quality can be improved.

Note that the outer peripheral surface 45 of the carrier surface plate not only causes surface wobbling in the radial direction but is also distorted and wavy in the vertical direction, and when the carrier surface plate 40 is rotated, the magnet array that is the detection object Is displaced in the radial direction and the vertical direction. Therefore, when the rotation detection sensor 165 is fixed to the base frame 151, the detection target 166 may be out of the detection area of the rotation detection sensor 165. Therefore, in the polishing system 1, the rotation detection sensor 165 is connected to the roller arm 12.
The rotation detection sensor 165 is provided at the leading end of 0 and is configured to always face the outer peripheral surface 45 of the carrier surface plate at a constant interval.

In addition, as shown in FIG. 6, when a plurality of rotation detection sensors 165 are arranged in the vertical direction at the tip of the roller arm 120 and the detected body 166 is relatively displaced in the vertical direction as the carrier surface plate 40 rotates. At least one of the rotation detection sensors 165 is disposed so as to detect the detected object 166. The output circuits of the plurality of rotation detection sensors 165, 165,... Are connected in parallel to form a wired OR circuit, and a low-pass filter circuit is interposed to prevent chattering. For this reason, the detected object 166 is reliably detected by the rotation detection sensor 165 in a state where the carrier surface plate 40 is rotated, and the rotation speed ω of the carrier surface plate 40 is always stably detected with high accuracy. ing. The detected actual rotation speed of the carrier platen 40 is fed back to the speed control of the entire roller drive unit as described above and displayed on the rotation display 88 provided in the control device 80.

A rotation detection sensor 165 is disposed at the tip of the roller arm 120 so as to be movable up and down corresponding to the height range in which the detected object 166 is relatively displaced.
5 may be provided so that the control device 80 moves the rotation detection sensor 165 up and down in accordance with the rotation angle posture of the carrier surface plate 40. That is, the detected object 166 together with the contour shape of the outer peripheral surface 45 of the carrier surface plate in the coordinate system described above.
Are stored in the memory 81, the rotational angle and orientation of the carrier surface plate 40 detected by the angular position detection device 161, and the height of the detected object 166 corresponding to the angular position stored in the memory 81. The rotation detection sensor 165 is controlled to move up and down based on the position. Even in such a configuration, the detection object 166 is reliably detected by the rotation detection sensor 165, and the rotation speed of the carrier surface plate 40 can be stably detected with high accuracy.

Next, the polishing system 1 'of the second configuration form will be described with reference to the block diagram shown in FIG. 7 corresponding to FIG. 4 and the schematic diagram shown in FIG. 8 corresponding to FIG. This polishing system 1
′, The radial position detection unit 160 ′ includes a circumferential surface displacement detection device 261 that detects a displacement state of the outer circumferential surface 45 that is displaced as the carrier surface plate 40 rotates, and is detected by the circumferential surface displacement detection device. Based on the displacement state of the peripheral surface, it is configured to detect the radial position of the peripheral surface passing through the roller arrangement region in each roller driving unit.

The peripheral surface displacement detection device 261 mainly includes a peripheral surface position detection sensor 262 that detects the radial position of the outer peripheral surface 45 of the carrier surface plate 40 and a rotation detection sensor 165 that detects the rotation state of the carrier surface plate. The displacement state of the peripheral surface is calculated by a CPU (arithmetic processing unit) 82 from the detected signal.

The circumferential surface position detection sensor 262 is provided at a predetermined angular position with respect to the roller drive unit 100 (in the illustrated configuration form, an angular position of θ _a = π / 4 [rad] with respect to the roller drive unit 100A). For example, a laser displacement meter provided facing the outer peripheral surface 45 of the carrier surface plate, or a CCD camera provided above the outer peripheral surface 45 of the carrier surface plate, and an image processing device for analyzing an image photographed by the CCD camera The radial position of the outer peripheral surface 45 at the angular position displaced in the radial direction with the rotation of the carrier surface plate 40 is detected.

Further, the rotation detection sensor 165 for detecting the rotation state of the carrier surface plate is configured in the same manner as the polishing system 1 of the first configuration form, and the outer peripheral surface 45 of the carrier surface plate 40 is arranged at a predetermined angular pitch around the virtual center O. By detecting a plurality of fixed detection bodies 166 by a rotation detection sensor 165 arranged at the tip of the roller arm 120 and counting the number of pulses detected per unit time, the rotation speed ω of the carrier surface plate 40 is detected. Configured to detect [rad / sec].

Based on the radial position of the outer peripheral surface 45 at the arrangement angle position of the peripheral surface position detection sensor 262 detected in this way and the rotational speed of the carrier surface plate 40, the control device 80 detects each roller drive unit 100. The moving position and rotational speed of the roller 110 are controlled.

For example, the relative angle θ _a = π / 4 [rad] formed by the arrangement angle position of the circumferential surface position detection sensor 262 and the arrangement angle position of the roller drive unit 100A, and the rotational speed ω [rad / sec]
The outer peripheral surface 45 detected by the peripheral surface position detection sensor 262 is the roller driving unit 1
A time t _a [sec] required to reach the angle position of 00A is calculated. That is, at the arrangement position of the roller drive unit 100A, the outer peripheral surface 45 of the displacement amount δ _p detected by the peripheral surface position detection sensor 262 arrives at a certain moment with _a delay of t _a [sec], and the same displacement waveform is delayed. Time t _a [sec]
Is played back periodically. The same applies to the other roller drive units 100B, 100C, and 100D, and the same displacement waveform is reproduced with a delay time corresponding to the relative angle to the circumferential surface position detection sensor 262.

FIG. 9 is a diagram schematically showing this state, and the displacement waveform of the outer peripheral surface 45 detected by the peripheral surface position detection sensor 262 is a base line in which a virtual circle C centered on the virtual center O is developed in a straight line. The displacement waveform swings up and down with respect to B, and is repeated at a constant period T. At the positions at which the roller drive units 100A, 100B, 100C, and 100D are arranged at 90 pitch equiangular positions, the displacement waveform of the outer peripheral surface 45 detected by the peripheral surface position detection sensor 262 is used as the delay times T / 8 and 3T, respectively. / 8, 5T / 8, 7T / 8 delayed waveform passing through each roller position 45
It becomes a waveform of the radial direction position.

Based on the displacement waveform of the outer peripheral surface 45 detected by the peripheral surface position detection sensor 262, the control device 80 controls the rotation of the roller moving motor 155 so that the roller 110 is positioned at the moving position delayed by each delay time. The outer peripheral surface 45 of the carrier platen with each roller 110 at a predetermined contact pressure
It is controlled so that it is pressed against. The rotational speed of each roller is the same as the peripheral speed at the radial position of the outer peripheral surface 45 detected by the peripheral surface position detection sensor 262 (the radius R of the virtual circle C + the displacement amount δ). The rotational speed of the roller drive motor 115 is controlled so as to match.

According to such a polishing system 1 ′, the carrier surface plate 40 is rotationally driven at a constant rotational speed ω about the virtual rotation axis as in the polishing system 1 of the first configuration form. In each roller drive unit 100 (100A, 100B, 100C, 100D), each roller 110 is always pressed against the outer peripheral surface 45 of the carrier surface plate with a constant contact pressure, and the outer periphery of the carrier surface plate is used for all rollers. The rotational driving force is transmitted with no speed difference from the surface 45. Therefore, stable and efficient rotation transmission is possible without causing uneven wear of each roller or energy loss due to a difference in peripheral speed. Further, since the carrier 30 is driven to rotate smoothly around the virtual center axis together with the carrier surface plate 40, the rotation axis of the substrate W held on the carrier 30 does not shake or discontinuously move, As a result, the polishing process can be stabilized and the polishing quality can be improved.

Similar to the polishing system 1, a reference member is provided on the carrier surface plate 40 to provide a carrier surface plate 40.
And a displacement amount δ to be detected at the reference angular position.
Is stored in the memory, and the base line B of the displacement waveform is preferably calibrated in comparison with the amount of displacement detected by the circumferential surface position detection sensor 262 at the reference angular position. Thereby, the movement position and rotation speed of each roller can be controlled with higher accuracy.

Further, in this configuration mode, the configuration in which the peripheral surface position detection sensor 262 is provided at one location on the outer peripheral side of the carrier surface plate is exemplified, but a plurality of configurations may be provided, for example, corresponding to each roller driving unit. You may comprise so that it may arrange | position.

Further, in each of the above-described configuration forms, as the means for detecting the rotation speed ω [rad / sec] of the carrier surface plate, the detected bodies 166 are provided on the outer peripheral surface 45 of the carrier surface plate 40 at an equiangular pitch, and the rotation detection sensor The configuration of calculating from the number of pulses detected per unit time by 165 is illustrated.
However, the means for detecting the rotation speed of the carrier surface plate 40 may have other configurations, for example,
Objects to be detected 166 at regular intervals (for example, 100 mm pitch) in the circumferential direction on the outer peripheral surface 45 of the carrier surface plate.
From the number of pulses detected per unit time by the rotation detection sensor 165.
5 is calculated, that is, the rotational speed ω [rad / sec] is calculated from this and the radial distance r [mm] of the outer peripheral surface, or the peripheral speed v [mm / sec] is calculated. The rotation speed of each roller may be directly controlled by [sec].

Furthermore, although the configuration in which the roller drive unit 100 is provided at four locations has been illustrated, it is sufficient if the configuration is such that the hollow annular carrier surface plate rotates about the axis of the virtual center O. It can be appropriately increased or decreased according to the size, weight, etc.

W Substrate 1,1 ′ Polishing system 10 Upper surface plate 20 Lower surface plate 30 Carrier 31 Substrate receiving portion 40 Carrier surface plate 50 Carrier surface plate drive mechanism 80 Controller 81 Memory 100 (100A, 100B, 100C, 100D) Roller drive unit 110 Roller 112 Roller shaft 115 Roller drive motor 120 Roller arm 125 Slide guide 127 Spring 130 Slide block 150 Roller moving structure 152 Slide guide 154 Ball screw 155 Roller moving motor 156 Ball nuts 160 and 160 ′ Radial position detecting section (radial position detecting means )
161 Angular position detection device 162 Reference position detection sensor 165 Rotation detection sensor 166 Detected object 261 Peripheral surface displacement detection device 262 Peripheral surface position detection sensor

The present invention relates to a polishing system that flat polished substrate, noted in particular, the carrier plate for supporting the substrate is disposed between the upper and lower platens, and Ruki Yaria platen carrier plate is rotated The present invention relates to a polishing system having a drive mechanism.

In order to achieve the above object, a polishing system of the present invention is provided between an upper surface plate and a lower surface plate, which are provided facing each other vertically, and between a top surface plate and a lower surface plate, and a carrier surface that supports a substrate. and board, constituted by a Ruki Yaria platen drive mechanism to rotate the carrier plate. Then, the carrier plate drive mechanism biases and against the outer circumferential surface rotation rotatably supported roller carrier plate, a roller roller driving motor for rotating and the roller on the outer peripheral surface side of the carrier plate And an urging portion that elastically contacts the outer peripheral surface, and is configured to rotate the carrier surface plate by rotating the roller by a roller drive motor.

In the polishing system configured as described above, the carrier surface plate driving mechanism preferably includes a roller moving mechanism that moves the roller in the radial direction of the carrier surface plate .

Further, in the polishing system having the above-described configuration, a radial position detection unit that detects a radial position of an outer peripheral surface of the carrier surface plate with which the roller in the carrier surface plate driving mechanism contacts, and the outer periphery detected by the radial position detection unit Depending on the radial position of the surface, the roller moving position by the roller moving mechanism and the rotation of the roller by the roller driving motor so that the contact state between the roller in the carrier surface driving mechanism and the outer peripheral surface of the carrier surface is constant. And a control device for controlling the speed .

In the polishing system configured as described above, it is preferable that the carrier surface plate driving mechanism includes a plurality of roller driving units each having a roller, a roller driving motor, and an urging portion . Moreover, it is preferable that a carrier surface plate is comprised so that a board | substrate may be supported via the carrier which has a board | substrate accommodating part.

In the polishing system of the present invention, the carrier surface plate driving mechanism includes a biasing portion that biases the roller toward the outer peripheral surface side of the carrier surface plate and elastically contacts the outer peripheral surface. Therefore , even if there is radial runout on the peripheral surface of the carrier surface plate, this radial runout can be absorbed by the biasing part, so the contact state between the peripheral surface of the carrier surface plate and the roller is made uniform. Thus, a polishing system capable of efficiently transmitting rotation can be provided.

In the polishing system 1 of the first configuration form, the radial position detection unit 160 detects the rotational angle position of the memory 81 in which the shape of the outer peripheral surface 45 of the carrier surface plate is preset and stored, and the carrier surface plate 40. The roller 110 in each roller drive unit 100 based on the shape of the outer peripheral surface set and stored in the memory 81 and the rotational angular position of the carrier surface plate 40 detected by the angular position detector 161. It is comprised so that the radial direction position of the outer peripheral surface which passes the arrangement | positioning area | region may be detected. The polishing system 1 will be described with reference to the block diagram shown in FIG.

A carrier at an arbitrary time is determined from the reference angle position of the carrier surface plate 40 detected by the reference position detection sensor 162 and the rotational speed ω of the carrier surface plate 40 detected based on the detection signal of the rotation detection sensor 165. Each roller drive unit 100 (100A, 100B, 100C, 100D) can be detected by rotating the profile Pf of the outer peripheral surface 45 set and stored in the memory 81 to the angular posture. The radial position of the outer peripheral surface 45 where the roller 110 should be located can be obtained. For example, the radial position where the roller 110 of the roller drive unit 100A should be located is obtained from the position PA (rA, θA) of the outer peripheral surface 45 passing through the roller position of the roller drive unit 100A.

In addition, as shown in FIG. 6, when a plurality of rotation detection sensors 165 are arranged in the vertical direction at the tip of the roller arm 120 and the detected body 166 is relatively displaced in the vertical direction as the carrier surface plate 40 rotates. At least one of the rotation detection sensors 165 is disposed so as to detect the detected object 166. The output circuits of the plurality of rotation detection sensors 165, 165,... Are connected in parallel to form a wired OR circuit, and a low-pass filter circuit is interposed to prevent chattering. Therefore, the detected body 166 is reliably detected by the rotation detection sensor 165 in a state where the carrier surface plate 40 is rotated, and the rotation speed ω of the carrier surface plate 40 is always stably detected with high accuracy. ing. The detected actual rotation speed of the carrier platen 40 is fed back to the speed control of the entire roller drive unit as described above and displayed on the rotation display 88 provided in the control device 80.

Claims (1)

Disc-shaped upper and lower surface plates provided facing each other vertically, a carrier having a substrate housing portion for holding a substrate and disposed between the upper surface plate and the lower surface plate, the upper surface plate And a carrier surface plate formed in an annular shape having a larger diameter than the lower surface plate and having the carrier connected to the inner periphery thereof, and the carrier surface plate being rotated between the upper surface plate and the lower surface plate. A carrier surface plate drive mechanism for rotating the sandwiched carrier,
The carrier surface plate driving mechanism includes a roller whose outer peripheral surface is in contact with the peripheral surface of the carrier surface plate and is supported so as to be rotatable about a roller shaft extending vertically, a roller driving motor for rotating the roller, and the roller It has a roller movement structure that moves in the radial direction of the carrier surface plate, and comprises a plurality of roller drive units that rotate the carrier surface plate by rotating the roller by the roller drive motor,
A radial position detecting means for detecting a radial position of the peripheral surface of the carrier surface plate passing through a region where the roller is provided in each roller driving unit;
A control device for controlling the moving position of the roller by the roller moving structure of each roller driving unit and the rotational speed of the roller by the roller driving motor;
According to the radial position of the peripheral surface detected by the radial position detecting means, the control device makes the contact state between the peripheral surface of the carrier surface plate and the roller of each roller drive unit constant. The polishing system is configured to control the moving position and the rotational speed of the roller in each of the roller driving units.

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