JPH1177520A - Polishing method and polishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lower manufacturing costs by extending the life of a polishing pad for a polishing process of a wafer and the like. SOLUTION: This polishing device is equipped with a polishing pad 1 polishing a wafer 10 while it is being rotated, a rotation driving part 11 drivingly rotating the polishing pad 1, a rocking mechanism 15 making rocking movement in such a way that the wafer 10 is reciprocated in the diametrical direction over the polishing pad 1, a position detecting device 19 detecting the position of the wafer 10 in the diametrical direction over the polishing pad 1, and with a rocking velocity control device 16 changing the velocity of rocking movement in response to the detected position of the wafer 10. The aforesaid device is provided with a press control device 18 controlling a pressing mechanism 17 in such a way that pressing force pressing the wafer 10 onto the polishing pad 1 is changed in response to the detected position of the wafer 10. And furthermore, the device is provided with rotation angular velocity control devices 12 and 14 which execute control in such a way that both the rotational velocity of the polishing pad 1 and the angular velocity of the wafer 10 can be changed in response to the detected position of the wafer 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing method and a polishing apparatus for flattening a material to be polished such as a wafer by a polishing member in the manufacture of a semiconductor device or the like.

[0002]

2. Description of the Related Art Although the density of semiconductor devices has continued to evolve without showing a limit, one of various problems to be overcome with the increase in density is the global (in a relatively large area) device. There is flattening of the surface. As the degree of device integration increases, further lamination of electrodes and the like is inevitable. In consideration of the reduction in the depth of focus at the time of exposure accompanying the shortening of the wavelength of lithography, there is a great demand for improving the accuracy of flattening the interlayer layer at least in the range of the exposure area. In addition, a so-called inlay (plug, damasc) formed by embedding a metal electrode layer is formed.
ene)) is also high. In this case, it is absolutely necessary to remove and planarize an extra metal layer after lamination.

A number of methods for locally smoothing an interlayer layer by improving a film forming method and the like have been proposed and implemented, but an efficient flattening technique for a larger area, which is required in the future, is required. A polishing process called CMP is attracting attention. CMP (Chemical M
technical Polishing or Pla
The process of removing the surface irregularities of a wafer by using physical polishing and chemical polishing by a chemical action (dissolution by an abrasive or a solution) in combination with physical polishing. It is the leading candidate. Specifically, using an abrasive called a slurry in which abrasive particles (typically silica, alumina, cerium oxide, etc.) are dispersed in a soluble solvent of the abrasive, such as an acid and an alkali, using an appropriate polishing cloth, Polishing is advanced by pressing the wafer surface and rubbing by relative motion. By making the pressure and the relative movement speed uniform over the entire surface of the wafer, uniform polishing within the surface becomes possible.

[0004] This process still has many problems in terms of matching with a conventional semiconductor process. One of the problems is that the process cost is high, which is largely due to the insufficient life of the polishing pad, which is a polishing consumable.

A polishing pad usually has a two-layer structure of a polishing layer made of a foam material such as urethane and an elastic layer for providing elasticity. The elastic layer deteriorates (so-called sag), and as a result, the uniformity of wafer polishing is impaired. This is considered to be the life of the pad, and many of them are currently replaced with about 1000 wafers. As described above, the polishing pad in the CMP polishing step has a life due to its wear or elastic deterioration. In order to extend the life of the polishing pad, improvement of the material of the polishing pad itself is awaited.

[0006]

On the other hand, in addition to the above-mentioned improvement of the material of the polishing pad, it is also necessary to extend the life of the polishing pad by averaging the wear amount and elastic deterioration of the polishing pad itself in the polishing pad surface. Conceivable.

SUMMARY OF THE INVENTION It is an object of the present invention to prevent abrasion and deterioration of a polishing pad, which is a polishing member, from being offset in the surface of a polishing pad, and to prolong the life of a polishing pad in a polishing process of a wafer, etc., to be polished. An object of the present invention is to provide a polishing method and a polishing apparatus capable of reducing costs.

[0008]

In order to achieve the above object,
The inventor of the present invention puts an object to be polished on a disk-shaped polishing member, rotates the polishing member, and polishes the object to be polished while swinging the material to reciprocate in the diameter direction of the polishing member. It has been found that the degree of wear and deterioration of the polishing member changes depending on the position of the material to be polished in the diametrical direction, and as a result of earnest efforts based on such knowledge, the present invention has been achieved.

That is, in the first polishing method of the present invention, a polishing target is placed on a rotating disk-shaped polishing member, and the polishing target is oscillated so as to reciprocate in the diameter direction of the polishing member. In the polishing method for polishing flat while polishing, a position detecting step of detecting a position of the polished material in a diameter direction of the polishing member, and changing a speed of the oscillating motion according to the detected position of the polished material. And a swing speed control step of causing the swing speed to be controlled.

According to the first polishing method of the present invention, the amount of wear and the degree of deterioration on the polished surface of the polishing member are changed by changing the speed of the oscillating motion in accordance with the position of the polished material being oscillated. Can be controlled, so that the wear amount and deterioration of the polishing member can be averaged. Therefore, it is possible to extend the life of the polishing member, and to reduce the manufacturing cost related to polishing. Note that the present polishing method can also be applied to a case where the workpiece is polished while rotating the workpiece itself.

In a second polishing method according to the present invention, a material to be polished is placed on a rotating disk-shaped polishing member, and the material to be polished is oscillated so as to reciprocate in the diameter direction of the polishing member. In the polishing method for polishing flat while polishing, a position detecting step of detecting a position of the polished member in a diameter direction of the polishing member, and the polished member is polished according to the detected position of the polished member. And a pressurizing control step of changing a pressurizing force applied to the pressurizing member.

According to the second polishing method of the present invention, by changing the pressing force for pressing the polished material against the polishing member in accordance with the position of the polished material while swinging, the wear on the polished surface of the polishing member is changed. Since the amount and degree of deterioration can be controlled, the wear amount and deterioration of the polishing member can be averaged. Therefore, the life of the polishing member can be extended,
A reduction in manufacturing cost for polishing can be achieved. Note that the present polishing method can also be applied to a case where the workpiece is polished while rotating the workpiece itself.

In a third polishing method according to the present invention, a material to be polished is placed on a rotating disk-shaped polishing member, and the material to be polished is oscillated so as to reciprocate in a diameter direction of the polishing member. In the polishing method of polishing flat while, the position detection step of detecting the position of the material to be polished in the diameter direction of the polishing member, while rotating the material to be polished, when polishing the material to be polished, A rotational angular velocity control step of changing at least one of a rotational angular velocity of the polishing member and a rotational angular velocity of the workpiece according to the detected position of the workpiece.

According to the third polishing method of the present invention, by changing at least one of the rotational angular velocity of the polishing member and the rotational angular velocity of the workpiece according to the position of the workpiece during swinging, Since the wear amount and the degree of deterioration on the polishing surface of the polishing member can be controlled, the wear amount and deterioration of the polishing member can be averaged. Therefore, it is possible to extend the life of the polishing member, and to reduce the manufacturing cost related to polishing.

Further, in the above-mentioned first polishing method, a pressurizing control step of changing a pressing force for pressing the polished material against the polishing member in accordance with the detected position of the polished material; When polishing the workpiece while rotating the workpiece itself, at least one of the rotation angular velocity of the polishing member and the rotation angular velocity of the workpiece is changed according to the detected position of the workpiece. And / or at least one of the rotational angular velocity control steps.

Thus, the wear amount and the deterioration of the polishing surface of the polishing member can be further averaged, so that the life of the polishing member can be further extended, which is preferable.

Further, the first polishing apparatus of the present invention comprises a disk-shaped polishing member for polishing a material to be polished while rotating, a rotary drive for rotating the polishing member, and the polishing member on the polishing member. A oscillating mechanism for oscillating the abrasive so as to reciprocate in the diameter direction of the polishing member; and a polishing apparatus for polishing the material to be polished flat, wherein the position of the object to be polished in the diameter direction of the polishing member is provided. And a rocking speed control device that controls the rocking mechanism to change the speed of the rocking motion according to the detected position of the workpiece. I do.

This first polishing apparatus can execute the first polishing method described above. Note that the present polishing apparatus may include another rotation drive unit that rotates the workpiece itself on the polishing member.

The polishing apparatus according to the second aspect of the present invention includes a disk-shaped polishing member for polishing the material to be polished while rotating, a rotation drive section for driving the polishing member to rotate, and the polishing member on the polishing member. A polishing apparatus that includes a swinging mechanism that swings an abrasive so as to reciprocate in the diameter direction of the polishing member and a pressing mechanism that presses the workpiece to the abrasive member, and that polishes the workpiece flat. A position detecting device for detecting a position of the polishing target in a diameter direction of the polishing member, and changing a pressing force for pressing the polishing target against the polishing member according to the detected position of the polishing target. And a pressurizing control device for controlling the pressurizing mechanism.

With the second polishing apparatus, the above-described second polishing method can be performed. Note that the present polishing apparatus may include another rotation drive unit that rotates the workpiece itself on the polishing member.

A third polishing apparatus according to the present invention includes a disk-shaped polishing member for polishing a material to be polished while rotating, a first rotation drive section for rotating and driving the polishing member, A oscillating mechanism for oscillating the polishing target so as to reciprocate in the diameter direction of the polishing member, and a second rotation drive unit for rotating the polishing target itself on the polishing member; In a polishing apparatus for polishing an abrasive material flatly, a position detecting device for detecting a position of the object to be polished in a diameter direction of the polishing member, and a rotational angular velocity of the polishing member according to the detected position of the object to be polished And a rotational angular velocity control device that controls at least one of the first rotational drive section and the second rotational drive section to change at least one of the rotational angular velocities of the workpiece.

With the third polishing apparatus, the above-described third polishing method can be performed.

Further, in the above-mentioned first polishing apparatus, a pressing mechanism for pressing the material to be polished against the polishing member, and the material to be polished to the polishing member in accordance with the detected position of the material to be polished. And a pressurizing control device that controls the pressurizing mechanism to change the pressing force.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view schematically showing a polishing apparatus according to an embodiment of the present invention. The polishing apparatus shown in FIG. 1 includes a polishing pad 1, a polishing platen 2 that fixes and rotates the polishing pad 1, a wafer head 3 that sandwiches a wafer 10 to be polished with the polishing pad 1, and a polishing platen 2. A polishing member rotation drive motor 11 that rotates around the rotation shaft 4 in the direction of arrow A, a polishing member rotation angular speed controller 12 that controls the rotation drive motor 11 to control the rotation angular speed of the polishing pad 1, and a wafer head 3 with an arrow. An object-to-be-polished material rotation drive motor 13 that is driven to rotate around the rotation axis 5 in the C direction, a material-to-be-polished rotation angle control device 14 that controls the rotation drive motor 13 and controls the rotation angular speed of the wafer head 3, and a wafer head 3. A swinging mechanism 15 for reciprocating in both directions of arrow B to make a swinging movement, a swinging speed controller 16 for controlling the swinging speed of the swinging mechanism 15, and a polishing head 1
Pressurizing mechanism 17 for pressing against
7 is provided with a pressurizing control device 18 for controlling the pressing force.

The polishing apparatus shown in FIG. 1 further includes a position detecting device 19 for detecting the position of the wafer 10 in the diameter direction of the polishing pad 1 and a CPU 20 to which a detection signal based on the position detection result of the position detecting device 10 is input. Prepare. CPU
20 sends control signals to the polishing member rotational angular velocity control device 12, the polished material rotational angular velocity control device 14, the oscillating velocity control device 16 and the pressurization control device 18 based on this detection signal, and based on this control signal. Control devices 12, 14, 1
Reference numerals 6 and 18 denote respective rotary drive motors 11 and 13 and a swing mechanism 15.
And the pressure mechanism 17 are controlled.

FIG. 2 is a plan view showing the position of the wafer 10 to be polished on the polishing pad 1. Polishing pad 1
1 is rotated in the direction A in FIG. 1 together with the polishing table 2 by the rotary drive motor 11 in FIG. 1, and the wafer 10 is polished by the swing mechanism 15 so as to reciprocate in the direction B, which is the diameter direction of the polishing pad 1. The wafer 10 is swung between the right end position R1 and the left end position R2 of the wafer 10 shown by oblique lines on the pad 1, and the wafer 10
It is driven to rotate in the direction.

FIG. 3 shows details of the pressure mechanism 17 shown in FIG. As shown in FIG. 3, the pressurizing mechanism 17 includes a fluid supply pump 17a, a passage 7a provided in the rotary shaft 5 so that the fluid from the pump 17a passes, and a pressure measurement sensor for detecting the pressure in the passage 7a. 17b, and annular openings 7b, 7c, 7d communicating with the passage 7a and provided on the contact surface 3a of the wafer head 3 with the wafer 10. Each of the openings 7b, 7c, 7d is formed in a concentric annular groove centered on the rotating shaft 5. As the fluid, a gas such as air and a liquid such as water can be used.

The fluid pressurized by the fluid supply pump 17a presses the wafer 10 against the polishing pad 1 at the annular openings 7b, 7c, 7d via the passage 7a. The pressing force is controlled by changing the fluid supply pressure of the pump 17a via the pressurizing control device 18 by a control signal sent from the CPU 20 based on the diametrical position of the wafer 10 on the polishing pad 1.

The swinging mechanism 15 engages, for example, the rotary shaft 5 in a straight guide groove (not shown) provided in the diameter direction of the polishing pad 1 so that the rotary shaft 5 is moved in the direction B in FIG. It can be constituted by a mechanism for reciprocating while moving straight by a stepping motor (not shown) or the like.

Further, the position detecting device 19 can be composed of, for example, an encoder for detecting a linear position of a linear motion of the rotating shaft 5 in the B direction.

The operation of the above polishing apparatus will be described. After the wafer 10 is placed on the polishing pad 1 and the upper surface of the wafer 10 is covered with the wafer head 3, as shown in FIG. 3, the wafer is moved from the pump 17a of the pressurizing mechanism 17 via the passage 7a to the annular openings 7b, 7c, 7d. Press against
Next, the polishing pad 2 on which the wafer 10 is mounted is rotated in the direction A by rotating the polishing platen 2 by the rotation drive motor 11. At the same time, by rotating the wafer head 3 in the direction C by the rotation drive motor 13, the wafer 10 itself pressed against the wafer head 3 is rotated.
Then, the swinging mechanism 15 moves the wafer head 3 to the position B in FIG.
The wafer 10 is swung in the diameter direction of the polishing pad 1 by reciprocating in the direction. While performing this operation, a slurry-like abrasive is discharged from the discharge port (not shown) of the polishing material nozzle onto the polishing pad 1, and the wafer 10 to be polished is placed on the lower surface of the polishing pad 1 as a polishing member. CM
Polish by the P polishing method.

In the operation described above, the polishing pad 1
The position of the wafer head 3 oscillating in the diameter direction is detected by the position detecting device 19. In accordance with a control signal from the CPU 20 based on the detected position information, each of the rotary drive motors 11 and 13, the swing mechanism 15 and the pressure mechanism 17 are controlled in accordance with the position of the wafer 10 in the diameter direction of the polishing pad 1.

Next, according to the position of the wafer 10 in the diameter direction of the polishing pad 1, each of the rotary drive motors 11, 1
3. How to control the swing mechanism 15 and the pressurizing mechanism 17 will be described.

First, the Preston's formula for polishing will be described. Polishing is performed by applying pressure between a polishing member (polishing pad 1) to be polished and a material to be polished (wafer 10), and further performing relative movement between the two. Here, there is a basic formula called the Preston's formula for polishing, which means that the polishing rate is proportional to the product of the pressure applied to the portion, the relative speed, and the polishing time. Normal appropriate polishing is performed within a range in which this relationship holds.

Next, based on this formula, an experiment was conducted in which the wafer was polished with a polishing pad larger than the wafer by a conventional polishing method while moving in the directions A, B and C shown in FIG. Will be described. The next-generation main wafer, 12 inch (about 30 cm) diameter wafer, 600m diameter
Polishing was performed with a polishing pad of m, 800 mm, and 1000 mm. Usually, in the CMP polishing, the wafer surface is uniformly pressurized. This is performed by giving a buffer effect to the polishing pad or the wafer holder by using an elastic member or the like. Therefore, from the Preston's equation, to achieve uniform polishing in the wafer plane, uniformity of the relative speed in the plane is required, and this makes the rotational speeds of the wafer and the pad equal in the same direction. It becomes possible by doing. Here, all were set to 40 rpm.

The swing speed is a general sinusoidal wave.
In the direction B in FIG. 2, the wafer is rotated at a speed of 10 seconds from the pad end (position R1 in FIG. 2) to the pad end (position R2 in FIG. 2) with uniform pressing and uniform relative speed. Was polished. In this case, it was found that the wafer surface was uniformly polished, but the polishing pad surface was worn or elastically degraded in accordance with Preston's formula, and distributions were produced in the manner of reduction and degree of degradation.

FIG. 4 shows the distribution of the amount of wear on the polishing pad surface according to the experiment conducted by the present inventor. The horizontal axis represents the distance from the center of the polishing pad, and the vertical axis represents the polishing rate of the polishing pad. 5 (when the diameter is also 800 mm) and FIG. 6 (when the diameter is 1000 mm).
mm). From FIG. 4 to FIG. 6, if the polishing time is sufficiently long, the wear amount distribution of the polishing pad becomes the central target,
Also, it can be seen that the wear amount of the polishing pad (represented by the wear amount speed in FIGS. 4 to 6) is considerably smaller at the outer peripheral portion than at the central portion.

By making the wear amount of the polishing pad uniform within the pad surface, the wear amount distribution of the polishing pad is obtained as shown in FIGS. 4 to 6, and the wear amount of the portion of the polishing pad where the wear amount is small is increased. Can be performed. That is,
In a portion of the polishing pad where the wear amount is small, a step of increasing the stay time of the wafer, a step of increasing the relative speed between the polishing pad and the wafer (an increase in the swing speed and an increase in the rotation speed), and This can be realized by a step of increasing the pressure. Even if these steps are performed, the actual polishing rate does not decrease, which is preferable in terms of productivity.

In the present embodiment, by performing these steps alone or in combination, it is possible to improve the average of the wear amount and the degree of deterioration of the pad surface of the polishing pad. That is, the wear amount and the degree of deterioration of the polishing pad are averaged according to the position of the wafer 10 in the diameter direction of the polishing pad 1 in the polishing apparatus of FIGS. The oscillating mechanism 15 and the pressing mechanism 17 are appropriately controlled to change the speed of the oscillating movement of the wafer 10, to change the pressing force for pressing the wafer 10 against the polishing pad 1, or to change the rotational angular speed of the polishing pad 1 and the wafer 10. It can be realized by changing the rotation angular velocity of.

More specifically, the swing speed of the wafer 10 is reduced near the outer periphery of the polishing pad 1 or stopped at the outermost peripheral portions of the positions R1 and R2 in FIG. Or by increasing the pressing force near the outer periphery of the polishing pad 1.

Next, an example in which a 12-inch wafer is actually polished by the polishing apparatus in the above embodiment will be described.

Example 1 The diameter of the polishing pad was 800 mm
In polishing the oxide film of a 12-inch wafer, the wear amount of the polishing pad was examined. The abrasive used was a slurry in which silica particles were dispersed in an alkaline solvent, and 100 g / cm
The wafer 10 was polished while pressing the wafer 10 against the polishing pad 1 at a constant pressure of about 2. As a material of the polishing pad 1, a CEP (Car
Bon Epoxy Polisher) was used.

In FIG. 1, the swinging speed of the wafer 10 is reduced near the outer periphery of the polishing pad 1 based on the actual wear amount distribution shown in FIG. The outermost portion (positions R1, R in FIG. 2)
By oscillating the wafer 10 stopped in 2), the wear amount of the polishing pad was averaged.

By controlling the stop time to an appropriate value,
A polishing amount distribution of the polishing pad 1 as shown in FIG. 7 can be obtained, and when compared with a conventional polishing method of polishing the same number of wafers with the same polishing amount, the wear of the most polished portion of the polishing pad is reduced. The amount could be reduced by about 40%. Therefore, the life of the polishing pad is extended by about 40% as compared with the conventional method.

<Second Embodiment> In the second embodiment, when the wafer is polished under the same conditions as those in the first embodiment except for the control of the swing speed, the pressing force for pressing the wafer 10 from the wafer head 3 onto the polishing pad 1 is used. , The wear of the polishing pad 1 was averaged. The swing speed is sinusoidal,
Based on the actual wear amount distribution shown in FIG. 4, the pressing force was controlled by the water pressure of the pump 17a in FIG. 3, and the outer peripheral portion was made larger (the maximum polishing pressure was about 140 g / cm ² ). in this way,
By increasing the pressure in a place where the polishing amount is small, the wear amount of the polishing pad could be averaged as shown in FIG.

According to the results of further study by the present inventor, the effect of increasing the swing speed for increasing the relative speed is relatively small, and it is difficult to rapidly change the rotation speed. Adjustment of the dwell time of the wafer during operation,
Adjusting the pressure on the wafer has been found to be more effective.

It should be noted that the present invention is not limited to the above-described first and second embodiments, and various modifications can be made within the scope of the technical idea of the present invention. The adjustment of the pressing force may be controlled simultaneously.
Further, both rotational angular velocities of the polishing pad 1 and the wafer 10 may be further controlled.

Further, the material of the polishing member is not limited to the above-mentioned one, and may be, for example, a urethane foaming agent or the like, and the polishing agent also depends on the state of the polished portion of the material to be polished. It can be selected as appropriate.

[0049]

According to the present invention, it is possible to prevent the amount of wear and deterioration of the polishing member from being offset in the plane of the polishing member, to prolong the life of the polishing member in the polishing step of the material to be polished, and to reduce the manufacturing cost. It is possible to provide a polishing method and a polishing apparatus that can be used.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a polishing apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view showing a polishing pad and a wafer of the polishing apparatus of FIG.

FIG. 3 is a view showing details of a pressing mechanism of the polishing apparatus of FIG. 1;

FIG. 4 shows a case where a 12-inch diameter silicon wafer is polished with a polishing pad having a diameter of 600 mm by a conventional polishing method.
FIG. 4 is a diagram showing a wear amount distribution of the polishing pad based on a relationship between a polishing speed of the polishing pad and a distance from a center of the polishing pad.

FIG. 5 shows a case where a 12-inch diameter silicon wafer is polished with an 800 mm-diameter polishing pad by a conventional polishing method.
FIG. 4 is a diagram showing a wear amount distribution of the polishing pad based on a relationship between a polishing speed of the polishing pad and a distance from a center of the polishing pad.

FIG. 6 shows a distribution of abrasion amount of a polishing pad when a 12-inch diameter silicon wafer is polished with a polishing pad having a diameter of 1000 mm by a conventional polishing method, based on a relationship between a polishing speed of the polishing pad and a distance from the center of the polishing pad. FIG.

FIG. 7 is a graph showing the relationship between the polishing rate of the polishing pad and the distance from the center of the polishing pad when the silicon wafer having a diameter of 12 inches is polished with the polishing pad of 800 mm in Example 1. FIG.

FIG. 8 is a graph showing the relationship between the polishing rate of the polishing pad and the distance from the center of the polishing pad when the silicon wafer having a diameter of 12 inches is polished with the polishing pad having a diameter of 800 mm in Example 2. FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Polishing pad (polishing member) 2 Polishing platen 3 Wafer head 10 Wafer (material to be polished) 11 Polishing member rotation drive motor (first rotation drive unit) 12 Polishing member rotation angular velocity control device 13 Polishing material rotation drive motor ( Second rotation drive unit) 14 Abrasive material rotation angular velocity control device 15 Oscillating mechanism 16 Oscillation speed control device 17 Pressurizing mechanism 17a Fluid supply pump 18 Pressurization control device 19 Position detecting device 20 CPU A Polishing pad rotation direction B Direction of swing motion of wafer C Rotation direction of wafer

Claims (8)

[Claims] 1. A polishing method in which a material to be polished is placed on a rotating disk-shaped polishing member, and the material to be polished is polished flat while being oscillated so as to reciprocate in the diameter direction of the polishing member. A position detecting step of detecting a position of the polished material in a diameter direction of the polishing member; and a swing speed controlling step of changing a speed of the oscillating motion according to the detected position of the polished material. A polishing method characterized by the above-mentioned. 2. A polishing method in which a material to be polished is placed on a rotating disk-shaped polishing member, and the material to be polished is polished flat while being oscillated so as to reciprocate in the diameter direction of the polishing member. A position detecting step of detecting a position of the polishing target in a diameter direction of the polishing member; and a pressurizing control for changing a pressing force for pressing the polishing target against the polishing member according to the detected position of the polishing target. And a polishing method. 3. A polishing method in which a material to be polished is placed on a rotating disk-shaped polishing member, and the material to be polished is polished flat while being oscillated so as to reciprocate in the diameter direction of the polishing member. A position detection step of detecting a position of the polished material in a diameter direction of a polishing member, and while rotating the polished material itself, when polishing the polished material, the detected position of the polished material is A rotational angular velocity control step of changing at least one of the rotational angular velocity of the polishing member and the rotational angular velocity of the workpiece to be polished. 4. A pressure control step of changing a pressing force for pressing the material to be polished against the polishing member according to the detected position of the material to be polished, and a step of rotating the material to be polished itself while rotating the material to be polished. When polishing an abrasive, at least one of a rotational angular velocity control step of changing at least one of a rotational angular velocity of the polishing member and a rotational angular velocity of the workpiece according to the detected position of the workpiece. 2. The polishing method according to claim 1, further comprising the step of: 5. A disk-shaped polishing member for polishing a material to be polished while rotating; a rotation drive unit for driving the polishing member to rotate; A polishing device, comprising: a swing mechanism for swinging back and forth, wherein the polishing device polishes the material to be polished flatly; a position detection device that detects a position of the material to be polished in a diameter direction of the polishing member; A oscillating speed control device that controls the oscillating mechanism so as to change the speed of the oscillating motion according to the position of the polished workpiece. 6. A disk-shaped polishing member for polishing a material to be polished while rotating; a rotation drive unit for rotating and driving the polishing member; A polishing mechanism, comprising: a swinging mechanism for swinging to reciprocate; and a pressing mechanism for pressing the material to be polished against the polishing member, wherein the polishing device polishes the material to be polished flat, A position detecting device for detecting a position of the polished material; and a pressurizing device for controlling the pressurizing mechanism to change a pressing force for pressing the polished material against the polishing member in accordance with the detected position of the polished material. A polishing apparatus, comprising: a control device. 7. A disk-shaped polishing member for polishing a material to be polished while rotating, a first rotation drive section for rotating and driving the polishing member, and A polishing apparatus, comprising: a swing mechanism that swings back and forth in a diametrical direction; and a second rotation drive unit that rotates the workpiece itself on the polishing member. A position detecting device for detecting a position of the polishing target in a diameter direction of the polishing member; and a rotational angular velocity of the polishing member and a rotational angular velocity of the polishing target according to the detected position of the polishing target. A polishing apparatus, comprising: a rotation angular velocity control device that controls at least one of the first rotation drive unit and the second rotation drive unit so as to change at least one of them. 8. A pressing mechanism for pressing the material to be polished against the polishing member; and a pressure mechanism for changing the pressure for pressing the material to be polished to the polishing member in accordance with the detected position of the material to be polished. A pressure control device that controls a pressure mechanism, and the first rotation drive that changes at least one of a rotation angular velocity of the polishing member and a rotation angular velocity of the workpiece according to the detected position of the workpiece. The polishing apparatus according to claim 5, further comprising: a rotation angular velocity control device that controls at least one of the unit and the second rotation drive unit.