Workpiece polishing device and polishing method

Abstract

To provide a workpiece double-sided polishing device and double-sided polishing method capable of accurately controlling a polishing amount and applicable not only to a rotation machine but also to a revolution machine.SOLUTION: A workpiece double-sided polishing device includes: a temperature measurement unit that measures the temperature on the double-sided polishing device; and a control unit that controls a polishing amount of the workpiece on the basis of the vibration at the measured temperature. The temperature measurement unit measures the temperature of polishing slurry on the outer peripheral portion of the double-sided polishing device. The workpiece double-sided polishing method includes a temperature measurement step of the temperature measurement unit measuring the temperature on the double-sided polishing device, in the temperature measurement step, the temperature of the polishing slurry on the outer peripheral portion of the double-sided polishing device being measured. The method further includes a control step of the control unit controlling the polishing amount of the workpiece on the basis of the vibration at the temperature of the polishing slurry measured in the temperature measurement step.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an apparatus and method for polishing a workpiece. [Background technology]

[0002] In the manufacture of semiconductor wafers such as silicon wafers, which are typical examples of workpieces to be polished, a double-sided polishing process is generally adopted in which the front and back sides are polished simultaneously in order to obtain higher precision in the flatness and surface roughness quality of the wafer. The shapes required for semiconductor wafers (mainly the flatness of the entire surface and the periphery) vary depending on the application, etc., and it is necessary to determine the target amount of polishing for the wafer according to each requirement and to accurately control the amount of polishing. In particular, in recent years, as semiconductor elements have become finer and semiconductor wafers have become larger in diameter, the requirements for flatness of semiconductor wafers during exposure have become more stringent. In light of this, there is a strong demand for a method for appropriately controlling the amount of wafer polishing.

[0003] In response to this, for example, in Patent Document 1, the applicant has proposed a method in which, in a double-sided polishing apparatus in which the carrier plate is a rotating machine that does not revolve around a rotating table, the temperature of the carrier plate is measured from the side of the polishing apparatus, and the amount of polishing of the workpiece is controlled based on changes in the phase and / or amplitude of the measured temperature. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-166677 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the above method was only applicable to rotating machines in which the carrier plate does not move on a surface plate. In other words, in a revolving machine in which the carrier plate revolves on a rotating surface plate, it is difficult to continuously measure the temperature of the carrier plate moving on the surface plate because the carrier plate revolves, and it is difficult to analyze the change in the temperature amplitude.

[0006] SUMMARY OF THE PRESENT DISCLOSURE ... An object of the present invention is to provide an apparatus and method for polishing both sides of a workpiece, which can accurately control the amount of polishing and can be applied not only to rotating machines but also to revolution machines. [Means for solving the problem]

[0007] As a result of extensive research, the inventors discovered that by measuring the temperature of the polishing slurry on the outer periphery of a double-sided polishing device in a rotating machine and a revolving machine, it is possible to accurately measure the temperature amplitude and accurately control the amount of polishing, and thus completed the present invention. The gist and configuration of the present invention are as follows.

[0008] (1) An apparatus for polishing both sides of a workpiece, comprising: a rotatable carrier plate in which one or more holding holes for holding a workpiece to be polished are formed, at least one of the holding holes being eccentrically disposed; a lower surface plate on which the carrier plate is placed; an upper surface plate that forms a pair with the lower surface plate; and polishing pads attached to each of the lower surface plate and the upper surface plate, a temperature measuring unit that measures a temperature on the double-sided polishing apparatus; A control unit that controls the amount of polishing of the workpiece based on the measured temperature vibration, 13. An apparatus for polishing both sides of a workpiece, wherein the temperature measuring unit measures the temperature of a polishing slurry on an outer periphery of the apparatus.

[0009] (2) The double-sided polishing apparatus for a workpiece described in (1) above, wherein the outer periphery is a side surface of the polishing pad and / or a side surface of the lower platen.

[0010] (3) The double-sided polishing apparatus for a workpiece described in (1) above, wherein the outer peripheral portion is between the lower platen and the upper platen and is a portion radially outer than the center of the retaining hole when the retaining hole is at its outermost position.

[0011] (4) The double-sided polishing apparatus for a workpiece described in (2) above, wherein the temperature measuring unit measures the temperature from diagonally above the polishing pad.

[0012] (5) The double-sided polishing apparatus for a workpiece according to (1) or (2), wherein the temperature measuring unit is an infrared radiometer.

[0013] (6) A method for simultaneously polishing the front and back surfaces of a workpiece by holding the workpiece on a carrier plate having one or more holding holes for holding the workpiece, at least one of the holding holes being eccentrically positioned, and rotating at least the carrier plate between a lower platen and an upper platen to which a polishing pad is affixed while supplying a polishing slurry, comprising: a temperature measuring step of measuring a temperature on the double-side polishing apparatus by a temperature measuring unit; In the temperature measuring step, a temperature of the polishing slurry on an outer periphery of the double-sided polishing machine is measured, A method for polishing both sides of a workpiece, further comprising a control step of controlling the amount of polishing of the workpiece by a control unit based on the temperature fluctuation of the polishing slurry measured in the temperature measurement step. Effect of the Invention

[0014] According to the present invention, it is possible to provide an apparatus and method for polishing both sides of a workpiece, which can accurately control the amount of polishing and can be applied not only to rotating machines but also to revolution machines.

[0015] In addition, by accurately controlling the amount of polishing, the yield when manufacturing a workpiece and the yield when manufacturing a device from a workpiece (e.g., a wafer) can be improved. The improvement of the yield increases the manufacturing efficiency of semiconductor products, making it possible to produce more high-quality products, and contributes to the promotion of technological innovation and the sustainable development of the industry. The improvement of the yield also reduces the waste of materials consumed in the manufacturing process of semiconductor products and contributes to the efficient use of resources. Furthermore, the improvement of the yield reduces the waste of energy consumed in the manufacturing process of semiconductor products, and as a result, contributes to the reduction of greenhouse gas emissions. In other words, the present invention makes it possible to contribute to, for example, "Goal 9: Industry, Innovation, and Infrastructure," "Goal 12: Ensure Sustainable Consumption and Production," and "Goal 13: Climate Change Action" in the Sustainable Development Goals (SDGs). [Brief description of the drawings]

[0016] [Figure 1] 1 is a top view of an apparatus for polishing both sides of a workpiece according to an embodiment of the present invention; [Diagram 2] 2 is a cross-sectional view taken along line AA in FIG. 1. [Diagram 3] FIG. 2 is a cross-sectional view of FIG. [Figure 4] FIG. 11 is a diagram showing the relationship between polishing time and the temperature of the polishing slurry on the side surface of the polishing pad on the upper platen side. [Diagram 5] FIG. 1 is a graph showing the relationship between polishing time and the thickness of a silicon wafer. [Figure 6] FIG. 11 is a graph showing the relationship between polishing time and the PP value A of the temperature of the polishing slurry on the side surface of the polishing pad on the upper platen side. [Figure 7] FIG. 13 is a diagram for explaining measurement points. [Figure 8] FIG. 13 is a diagram showing the relationship between the polishing time and the temperature amplitude for each measurement point. [Figure 9] FIG. 13 is a diagram showing a difference in temperature oscillation that can be obtained when the temperature measurement range is adjusted. [Figure 10]13 is a diagram for explaining a PP value A, an amplitude B, and an actual measurement value C. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0018] <Double-sided workpiece polishing device> Fig. 1 is a top view of an apparatus for polishing both sides of a workpiece according to an embodiment of the present invention. Fig. 1 shows the apparatus for polishing both sides of a workpiece as viewed from above with an upper surface plate and a polishing pad attached to the upper surface plate removed. Fig. 2 is a cross-sectional view taken along line AA in Fig. 1, and Fig. 3 is a cross-sectional view taken along line BB in Fig. 1.

[0019] As shown in Figures 1 to 3, the double-sided polishing apparatus 1 for workpieces of this embodiment includes a rotatable carrier plate 3 having one or more (only one in the illustrated example) holding holes 4 for holding a workpiece 2 (in this embodiment, a silicon wafer) to be polished, with at least one of the holding holes 4 positioned eccentrically, a lower surface plate 5b on which the carrier plate 3 is placed, an upper surface plate 5a that forms a pair with the lower surface plate 5b, and polishing pads 6b, 6a affixed to the lower surface plate 5b and the upper surface plate 5a, respectively.

[0020] The double-sided polishing machine 1 is equipped with multiple motors (not shown), and the upper and lower plates 5a and 5b are rotated in opposite directions by the motors. In the illustrated example, the center of the holding hole 4 is located away from the center of the carrier plate 3. The upper and lower plates 5a and 5b can clamp the workpiece 2 held in the holding hole 4 with a constant pressure.

[0021] The carrier plate 3 is provided with an outer circumferential gear (not shown) for meshing with the sun gear 7 and the internal gear 8 provided between the upper and lower plates 5a and 5b. Here, the sun gear 7 and / or the internal gear 8 are a driving mechanism that is driven by a motor different from the motor that rotates the upper and lower plates and rotates the carrier plate 3. The outer circumferential gear of the carrier plate 3 meshes with the sun gear 7 and the internal gear 8 to rotate the carrier plate 3. Note that the gear meshing of the sun gear 7, the internal gear 8, and the outer circumferential gear is not shown in order to simplify the double-sided polishing apparatus 1. The internal gear 8 is also composed of individual axle pins that are a number of rotation drive axle pins arranged in the circumferential direction, and each axle pin meshes with the outer circumferential gear of the carrier plate 3 to rotate the carrier plate 3. However, each axle pin is not shown in order to simplify the double-sided polishing apparatus 1.

[0022] Due to such gear meshing, the carrier plate 3 rotates around the center of the carrier plate 3 as a central axis (hereinafter simply referred to as "rotation") in accordance with the rotation of the lower platen 5b and the rotation of the sun gear 7 and / or the internal gear 8, and rotates around the sun gear 7 as a central axis (hereinafter simply referred to as "revolution"). In this embodiment, the center of the holding hole 4 is located away from the center of the carrier plate 3, that is, the workpiece 2 is eccentric with respect to the center of the carrier plate 3, so that the distance between the center of the upper platen 5a and the lower platen 5b and the center of the workpiece 2 changes periodically with each rotation. In the workpiece polishing device 1 of this embodiment, the front and back surfaces of the workpiece 2 are simultaneously chemically mechanically polished by the polishing pads 6a and 6b and the polishing slurry 9 while the sandwiched carrier plate 3 is rotated and revolved.

[0023] The workpiece double-sided polishing apparatus 1 of this embodiment further includes a temperature measuring unit 10 for measuring the temperature on the double-sided polishing apparatus 1. The temperature measuring unit 10 is configured to measure the temperature of the polishing slurry 9 on the outer periphery of the double-sided polishing apparatus 1 (for example, flowing on the outer periphery). The outer periphery is preferably the side of the polishing pads 6a, 6b and / or the side of the lower platen 5b. When measuring the temperature of the polishing slurry 9 on the side of the polishing pads 6a, 6b and / or the side of the lower platen 5b, the temperature measuring unit 10 preferably measures the temperature from obliquely above the polishing pads 6a, 6b. In this case, the temperature measuring unit 10 is preferably an infrared radiometer, and can be, for example, an infrared camera (especially, for example, one using infrared thermography). Alternatively, the outer periphery is preferably a portion between the lower platen 5b and the upper platen 5a, radially outward from the center of the holding hole 4 when the holding hole 4 of the rotating carrier plate is located at the outermost position. In this case, the temperature measuring unit 10 is preferably a thermocouple.

[0024] The double-sided polishing machine 1 for workpieces of this embodiment further includes a control unit 11 that controls the amount of polishing of the workpiece 2 based on the vibration of the temperature measured by the temperature measuring unit 10. The control unit 11 can be any known processor. The control unit 11 is connected to a motor included in the double-sided polishing machine 1 so as to perform wired or wireless communication (not shown). The control unit 11 is also connected to a temperature control unit 10 so as to perform wired or wireless communication (not shown). For example, the temperature measuring unit 10 transmits the temperature measured by the temperature measuring unit 10 to the control unit 11 by wired communication. The control unit 11 transmits a signal for controlling the motor of the double-sided polishing machine 1 based on the received temperature by wired communication.

[0025] <How to polish both sides of a workpiece> Although the method for polishing both sides of a workpiece according to one embodiment of the present invention is not particularly limited, as an example, it can be performed using the apparatus for polishing both sides of a workpiece 1 according to the above-mentioned embodiment. The matters already described for the embodiment of the apparatus for polishing both sides of a workpiece 1 will not be described again.

[0026] The method for polishing both sides of a workpiece in this embodiment involves holding the workpiece 2 on a carrier plate 3 having one or more holding holes 4 for holding the workpiece 2, with at least one of the holding holes 4 being eccentrically positioned, and simultaneously polishing the front and back sides of the workpiece 2 by rotating at least the carrier plate 3 between a lower platen 5b and an upper platen 5a to which polishing pads 6a, 6b are affixed while supplying a polishing slurry 9.

[0027] The method for polishing both sides of a workpiece in this embodiment includes a temperature measurement step of measuring the temperature on the double-sided polishing machine 1 by a temperature measurement unit 10. In the temperature measurement step, the temperature of the polishing slurry on the outer periphery of the double-sided polishing machine 1 is measured. The method for polishing both sides of a workpiece in this embodiment further includes a control step of controlling the amount of polishing of the workpiece by a control unit 11 based on the vibration of the temperature of the polishing slurry 9 measured in the temperature measurement step. The effects of this embodiment will be described below.

[0028] The double-sided polishing apparatus 1 for workpieces in this embodiment is equipped with a temperature measuring unit 10 that measures the temperature on the double-sided polishing apparatus 1, and a control unit 11 that controls the amount of polishing of the workpiece 2 based on the vibration of the measured temperature, and the temperature measuring unit 10 measures the temperature of the polishing slurry 9 on the outer periphery of the double-sided polishing apparatus 1. This makes it possible to constantly measure the temperature on the double-sided polishing apparatus 1, regardless of the timing of the rotation and revolution of the carrier plate 3. In addition, since it is easy to grasp the temperature vibration of the polishing slurry 9 on the outer periphery of the double-sided polishing apparatus 1, it is possible to accurately control the amount of polishing based on the vibration. As described above, according to the double-side polishing apparatus 1 for workpieces of this embodiment, the amount of polishing can be accurately controlled, and it is applicable not only to rotating machines but also to revolution machines.

[0029] The outer periphery is preferably the side of the polishing pads 6a, 6b and / or the side of the lower platen 5b. As will be shown in the examples below, the temperature fluctuation of the polishing slurry 9 on the side of the polishing pads 6a, 6b and / or the side of the lower platen 5b is particularly easy to grasp, so the amount of polishing can be controlled more accurately. In this case, the temperature measuring unit 10 is preferably configured to measure the temperature from obliquely above the polishing pads 6a, 6b. This is because it is easy to measure the temperature of the polishing slurry 9 on the side of the polishing pads 6a, 6b and / or the side of the lower platen 5b. Furthermore, from the viewpoint of suppressing adhesion of the scattered polishing slurry 9 and the cleaning liquid used for cleaning the platen to the temperature measuring unit 10, it is preferable that the temperature measuring unit 10 is located obliquely above the polishing pads 6a, 6b. In addition, in this case, an infrared radiometer is suitable for the temperature measuring unit 10.

[0030] On the other hand, the outer peripheral portion can also be the portion between the lower platen 5b and the upper platen 5a, radially outward from the center of the retaining hole 4 when the retaining hole 4 of the rotating carrier plate is at its outermost position.

[0031] In addition, the method for polishing both sides of a workpiece in this embodiment includes a temperature measurement process in which the temperature on the double-sided polishing apparatus 1 is measured by a temperature measurement unit 10, and in the temperature measurement process, the temperature of the polishing slurry on the outer periphery of the double-sided polishing apparatus 1 is measured, and further includes a control process in which the control unit 11 controls the amount of polishing of the workpiece based on the vibration of the temperature of the polishing slurry 9 measured in the temperature measurement process. This makes it possible to constantly measure the temperature on the double-sided polishing apparatus 1, regardless of the timing of the rotation and revolution of the carrier plate 3. In addition, since it is easy to grasp the temperature vibration of the polishing slurry 9 on the outer periphery of the double-sided polishing apparatus 1, it is possible to accurately control the amount of polishing based on the vibration. As described above, according to the method for polishing both sides of a workpiece of this embodiment, the amount of polishing can be accurately controlled, and it is applicable not only to rotating machines but also to revolution machines.

[0032] Even in the invention of the double-sided polishing method of the workpiece, the outer periphery is preferably the side of the polishing pads 6a, 6b and / or the side of the lower platen 5b. As will be shown in the examples described later, the amplitude of the temperature of the polishing slurry 9 on the side of the polishing pads 6a, 6b and / or the side of the lower platen 5b is particularly easy to grasp, so that the amount of polishing can be controlled more accurately. In this case, the temperature measuring unit 10 is preferably configured to measure the temperature from obliquely above the polishing pads 6a, 6b. This is because it is easy to measure the temperature of the polishing slurry 9 on the side of the polishing pads 6a, 6b and / or the side of the lower platen 5b. In addition, in this case, an infrared radiometer is suitable for the temperature measuring unit 10. On the other hand, the outer periphery can also be a portion between the lower platen 5b and the upper platen 5a, and radially outward from the center of the holding hole 4 when the holding hole 4 of the rotating carrier plate is located at the outermost position. EXAMPLES

[0033] Examples of the present invention will be described below, but the present invention is not limited to these examples.

[0034] Fig. 4 is a diagram showing the relationship between the polishing time and the temperature of the polishing slurry on the side surface of the polishing pad on the upper platen side when a 300 mm diameter p-type silicon wafer is double-sided polished using the double-sided polishing machine for workpieces as shown in Figs. 1 to 3. As shown in Fig. 4, it is clear that the temperature fluctuations over time can be easily grasped regardless of the polishing time (i.e., the timing of the rotation and revolution of the carrier plate) and at any of the five different measurement points.

[0035] When the temperature measuring unit 10 is configured as an infrared radiometer, the temperature measuring unit 10 measures the temperature of a region having a certain area of ​​the measurement target. From the viewpoint of clearly grasping the temperature fluctuation, it is preferable that the range in which the temperature measuring unit 10 measures the temperature is narrow. FIG. 9 is a diagram showing the difference in temperature vibration that can be obtained when the temperature measurement range is adjusted. The dotted line graph shows the temperature change over time when the temperature measurement range is a square with one side measuring 15 cm. The solid line graph shows the temperature change over time when the temperature measurement range is a square with one side measuring 10 cm. It can be seen from FIG. 9 that the temperature vibration can be obtained more clearly when the temperature measurement range is a square with one side measuring 10 cm. The range in which the temperature measurement unit 10 measures the temperature is preferably an area that fits within a square with one side measuring 10 cm, and can be, for example, a square area with one side measuring 10 cm or less, or a circular area with a diameter of 10 cm or less.

[0036] FIG. 5 is a diagram showing the relationship between the polishing time and the thickness of the silicon wafer. FIG. 6 is a diagram showing the relationship between the polishing time and the PP value A of the temperature of the polishing slurry on the side of the polishing pad on the upper platen side. Here, the PP value A is defined as the difference between the maximum value and the minimum value in one period of vibration, as shown in FIG. 10. FIG. 5 and FIG. 6 show the results of polishing under three conditions of low, normal, and high pressure. As shown in FIG. 5, there is a relationship between the polishing time and the thickness of the silicon wafer such that the thickness of the silicon wafer becomes thinner (almost linearly) as the polishing time becomes longer, and as shown in FIG. 6, there is a relationship between the polishing time and the PP value A of the temperature such that the PP value A of the temperature becomes smaller (to the extent that it can be linearly approximated) as the polishing time becomes longer. Therefore, if it is possible to grasp the temperature fluctuations as shown in FIG. 4, it is possible to calculate (estimate) the thickness of the silicon wafer by analyzing the change in the P-P value A due to the temperature fluctuations, and it is possible to appropriately determine the end time of polishing and accurately control the amount of polishing. For example, a relational equation between the P-P value A of temperature and the thickness of a silicon wafer may be obtained in advance, a mapping may be created, or machine learning may be performed using a sufficient number of data, thereby making it possible to obtain the P-P value A of temperature corresponding to the thickness of a silicon wafer, and the time at which the temperature amplitude reaches a value corresponding to a desired thickness can be determined as the end time of polishing.

[0037] In addition, as an index used to control the polishing apparatus, in addition to the above-mentioned PP value A, a parameter obtained from the temperature oscillation may be used. As shown in FIG. 10, the amplitude B defined as the width from the center of oscillation to the maximum or minimum value within one oscillation cycle, or the actual temperature measurement value C for each oscillation cycle may also be used.

[0038] Next, in order to identify the most suitable measurement object, the temperature of the polishing slurry on each of the measurement points, namely, the side of the upper platen, the side of the polishing pad on the upper platen side, the side of the polishing pad on the lower platen side, and the side of the lower platen, was measured, and the relationship between the polishing time and the temperature amplitude was tested. Fig. 7 is a diagram for explaining the measurement points, and Fig. 8 is a diagram showing the relationship between the polishing time and the temperature amplitude for each measurement point. In Fig. 7 and Fig. 8, "upper pad" refers to the polishing pad affixed to the upper platen, and "lower pad" refers to the polishing pad affixed to the lower platen. As shown in Fig. 8, the polishing slurry flowing on the side of the polishing pad and / or the side of the lower platen is suitable as the measurement object from the viewpoint of obtaining the temperature fluctuation more clearly, and the side of the polishing pad is more suitable. On the other hand, as shown in Fig. 7 and Fig. 8, the slurry was not flowing at the measurement point of the upper platen, so it was difficult to obtain the temperature fluctuation. The temperature is measured by placing the measurement target within the measurement range of the temperature measuring device 10, but is not limited to a form in which only the measurement target exists within the temperature measurement range. For example, the temperature at the measurement point of the upper pad is measured by placing the side surface of the polishing pad attached to the upper surface plate within the measurement range of the temperature measuring device 10, but since the polishing pad itself is thin, part of the side surface of the upper surface plate is also included within the measurement range of the temperature measuring device 10, but it is possible to obtain the temperature vibration as shown in FIG. [Explanation of symbols]

[0039] 1: Double-sided polishing device for workpieces, 2: Work (wafer), 3: carrier plate, 4: Retention hole, 5a: Upper surface plate, 5b: Lower surface plate, 6a, 6b: polishing pads, 7: Sun gear, 8: Internal gear, 9: abrasive slurry, 10: Temperature measurement part, 11: Control unit

Claims

1. An apparatus for polishing both sides of a workpiece, comprising: a rotatable carrier plate in which one or more holding holes for holding a workpiece to be polished are formed, at least one of the holding holes being eccentrically disposed; a lower surface plate on which the carrier plate is placed; an upper surface plate that forms a pair with the lower surface plate; and polishing pads attached to each of the lower surface plate and the upper surface plate, a temperature measuring unit that measures a temperature on the double-sided polishing apparatus; A control unit that controls the amount of polishing of the workpiece based on the measured temperature vibration, 13. An apparatus for polishing both sides of a workpiece, wherein the temperature measuring unit measures the temperature of a polishing slurry on an outer periphery of the apparatus.

2. The apparatus for polishing both sides of a workpiece according to claim 1 , wherein the outer periphery is a side surface of the polishing pad and / or a side surface of the lower platen.

3. 2. The apparatus for polishing both sides of a workpiece according to claim 1, wherein the outer peripheral portion is between the lower platen and the upper platen and is a portion radially outward of the center of the retaining hole when the retaining hole is at its outermost position.

4. The apparatus for polishing both sides of a workpiece according to claim 2 , wherein the temperature measuring unit measures the temperature from obliquely above the polishing pad.

5. 3. The apparatus for polishing both sides of a workpiece according to claim 1, wherein the temperature measuring unit is an infrared radiometer.

6. A method for simultaneously polishing the front and back surfaces of a workpiece, comprising: holding the workpiece on a carrier plate having one or more holding holes for holding the workpiece, at least one of the holding holes being eccentrically disposed; and rotating at least the carrier plate between a lower platen and an upper platen to which a polishing pad is attached while supplying a polishing slurry, the method comprising: a temperature measuring step of measuring a temperature on the double-side polishing apparatus by a temperature measuring unit; In the temperature measuring step, a temperature of the polishing slurry on an outer periphery of the double-sided polishing machine is measured, A method for polishing both sides of a workpiece, further comprising a control step of controlling the amount of polishing of the workpiece by a control unit based on the temperature fluctuation of the polishing slurry measured in the temperature measurement step.

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