Grinding device

Abstract

To provide a polishing device that can polish a work-piece with good accuracy.SOLUTION: A CMP device 1 comprises: a chuck 19 that can hold a work-piece W; second airbags 16A-16D that are arranged in parallel along a circumferential direction of the chuck 19, and inflated with air to enable a portion of the work-piece W to be pressed toward a polishing pad 5; and a controller 6 that can adjust pressure of air supplied to the second airbags 16A-16D.SELECTED DRAWING: Figure 2

Description

Technical Field

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[0001] The present invention relates to a polishing apparatus for polishing a workpiece.

Background Art

[0002] In the semiconductor manufacturing field, a CMP apparatus for polishing and planarizing a silicon wafer or the like (hereinafter referred to as "workpiece") is known.

[0003] The polishing apparatus described in Patent Document 1 is a polishing apparatus applying chemical mechanical polishing, so-called CMP (Chemical Mechanical Polishing) technology. This CMP apparatus presses a workpiece mounted on a polishing head against a polishing pad to polish the workpiece.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in back-surface reference polishing in which the back surface of the workpiece is held by the chuck of the polishing head and the front surface of the workpiece is pressed against the polishing pad for polishing, since the pressure distribution acting on the workpiece is set to be substantially uniform in the circumferential direction of the workpiece, there may be cases where the shape of the workpiece after polishing is inclined due to the crystal orientation of the workpiece, or a workpiece having an uneven initial film thickness in the circumferential direction cannot be polished to a uniform thickness.

[0006] Therefore, a technical problem to be solved in order to polish the workpiece with high accuracy arises, and an object of the present invention is to solve this problem.

Means for Solving the Problems

[0007] To achieve the above objective, the polishing apparatus according to the present invention is a polishing apparatus that polishes a workpiece held in a polishing head by pressing it against a polishing pad on a platen, On the holding surface as an abrasive surface A chuck capable of holding the workpiece, and arranged in parallel along the circumferential direction of the chuck, which are inflated by air. The pressure distribution within the polishing surface acting on the entire surface of the workpiece via the chuck is made non-uniform in the circumferential direction of the workpiece, and the non-uniform pressure distribution in the circumferential direction of the workpiece The aforementioned Ku The system includes multiple partial pressing sections that press toward the polishing pad, and a controller that can adjust the air pressure supplied to each partial pressing section.

[0008] With this configuration, by expanding and contracting multiple partial pressurizing sections, the pressure distribution acting on the workpiece can be freely adjusted in the circumferential direction of the workpiece. This allows the pressure distribution to be adjusted in the circumferential direction of the workpiece, taking into account the crystal orientation and non-uniform initial film thickness of the workpiece, and applying different polishing pressures to the workpiece within the polishing surface, thereby enabling the workpiece to be polished flat with high precision. [Effects of the Invention]

[0009] This invention enables the precise and flat grinding of a workpiece. [Brief explanation of the drawing]

[0010] [Figure 1] A schematic perspective view showing a CMP device according to one embodiment of the present invention. [Figure 2] A schematic longitudinal cross-sectional view showing the main parts of the polishing head. [Figure 3] A plan view showing the relative positions of the first and second airbags. [Figure 4] A plan view showing the positional relationship between the workpiece and the second airbag. [Figure 5] (a) is a schematic diagram showing the pressure distribution by the first airbag, and (b) is a schematic diagram showing the pressure distribution by the first airbag and the second airbag. [Figure 6] This image shows the pressure exerted on the workpiece W when each of the four second airbags was inflated and deflated. [Figure 7]A schematic diagram illustrating the process of calculating the air pressure supplied to the second airbag when a desired pressure is applied at an arbitrary peak position. [Figure 8] (a) is a graph showing the amount of material removed by polishing on the X axis in Examples 1 and 2 and Comparative Example 1, and (b) is a graph showing the amount of material removed by polishing on the Y axis in Examples 1 and 2 and Comparative Example 1. [Figure 9] (a) is a graph showing the amount of material removed by polishing on the X axis in Examples 3 and 4 and Comparative Example 2, and (b) is a graph showing the amount of material removed by polishing on the Y axis in Examples 3 and 4 and Comparative Example 2. [Figure 10] (a) is a graph showing the thickness of the workpiece on the X-axis in Example 5, and (b) is a graph showing the thickness of the workpiece on the Y-axis in Example 5. [Figure 11] (a) is a graph showing the amount of material removed by polishing on the X axis in Example 5, and (b) is a graph showing the amount of material removed by polishing on the Y axis in Example 5. [Figure 12] This graph shows the range of variation in workpiece thickness during each step of Example 5. [Modes for carrying out the invention]

[0011] One embodiment of the present invention will be described with reference to the drawings. In the following, when referring to the number, numerical values, quantities, ranges, etc., of components, unless specifically indicated or clearly limited to a particular number in principle, the number is not limited to that particular number and may be greater than or less than that number.

[0012] Furthermore, when referring to the shape, positional relationship, etc. of constituent elements, unless otherwise explicitly stated or it is clearly considered not to be so in principle, this includes things that are substantially similar or alike to those shapes, etc.

[0013] In addition, the drawings may be exaggerated, for example, by enlarging characteristic parts to make the features easier to understand, and the dimensional ratios of the components are not necessarily the same as the actual ones. Also, in sectional views, in order to make the sectional structure of the components easier to understand, the hatching of some components may be omitted.

[0014] FIG. 1 is a perspective view schematically showing a CMP apparatus 1 according to an embodiment of the present invention. The CMP apparatus 1 is for planar polishing of one surface of a workpiece W. The CMP apparatus 1 includes a platen 2 and a polishing head 10. The workpiece W is, for example, a silicon wafer, but is not limited thereto.

[0015] The platen 2 is formed in a disk shape and is connected to a rotating shaft 3 disposed below the platen 2. When the rotating shaft 3 rotates by driving of a motor 4, the platen 2 rotates in the direction of arrow D1 in FIG. 1. A polishing pad 5 is attached to the upper surface of the platen 2, and a CMP slurry, which is a mixture of an abrasive and a chemical, is supplied onto the polishing pad 5 from a nozzle (not shown).

[0016] The polishing head 10 is formed to have a smaller diameter than the platen 2 and is connected to a rotating shaft 10a disposed above the polishing head 10. When the rotating shaft 10a rotates by driving of a motor (not shown), the polishing head 10 rotates in the direction of arrow D2 in FIG. 1. The polishing head 10 is configured to be movable in the vertical and horizontal directions by a head moving mechanism (not shown). The polishing head 10 descends when polishing the workpiece W and presses the workpiece W against the polishing pad 5.

[0017] The operation of the CMP apparatus 1 is controlled by a controller 6. The controller 6 controls each of the components constituting the CMP apparatus 1. The controller 6 is, for example, a computer and is composed of a CPU, a memory, etc. Note that the functions of the controller 6 may be realized by control using software or may be realized by an operation using hardware.

[0018] Next, the structure of the polishing head 10 will be described. Figure 2 is a schematic longitudinal cross-sectional view showing the main part of the polishing head 10.

[0019] The polishing head 10 includes a head body 11 connected to a rotating shaft 10a. The head body 11 is connected to a base member 13 via a rotation transmission unit 12, and the head body 11, rotation transmission unit 12, and base member 13 rotate together with the rotating shaft 10a.

[0020] A plate holder 14 made of PPS is fastened to the upper part of the base member 13 via bolt B1. As a result, the rotational driving force input to the polishing head 10 is transmitted to the plate holder 14 via the base member 13.

[0021] A first airbag 15 and a second airbag 16 are interposed between the plate holder 14 and the head body 11.

[0022] The first airbag 15 is formed in a substantially annular shape. The first airbag 15 can be inflated and deflated by air supplied from a compressed air source (not shown) via a compressed air line 15a. The pressure of the air supplied from the compressed air source is adjusted by a regulator (not shown) controlled by a controller 6. The first airbag 15 adjusts the polishing pressure at which the entire workpiece W is pressed against the polishing pad 5 by pressurizing the entire plate holder 14 in accordance with the pressure of the supplied air.

[0023] There are four second airbags 16. The second airbags 16 are housed within the first airbags 15. As shown in Figure 3, the four second airbags 16 are each formed in a substantially circular shape and are arranged in substantially concentric circles around the rotation center of the polishing head 10 when viewed from above.

[0024] As shown in Figure 4, the four second airbags 16 are arranged one in the positive region and one in the negative region on each of the mutually orthogonal X-axis or Y-axis passing through the center of the workpiece W. Hereafter, when distinguishing between the four second airbags 16, the second airbag 16 located in the negative region on the Y-axis close to the orientation flat OF will have "a" appended to the end of its designation, and the second airbags 16 will be labeled "B", "C", and "D" in clockwise order when viewed from a plane, with the second airbag 16A as the reference. Note that the number of second airbags 16 installed is not limited to four; it may be three or less, or five or more.

[0025] The second airbag 16 is capable of being inflated and deflated by air supplied from a compressed air source (not shown) via a compressed air line 16a. The pressure of the air supplied from the compressed air source is adjusted by a regulator (not shown) controlled by a controller 6. The second airbag 16, in accordance with the pressure of the supplied air, pressurizes a portion of the plate holder 14 located directly below it, thereby locally changing the polishing pressure applied to the polishing pad 5 against the workpiece W in the circumferential direction of the workpiece W. Furthermore, because the second airbag 16 is fixed to the lower surface of the highly rigid head body 11 and configured to be inflatable downwards, the inflation and deflation of the second airbag 16 can be easily controlled compared to, for example, a case where the second airbag 16 is stacked on the lower surface of an inflatable first airbag 15.

[0026] Returning to Figure 2, a porous chuck 17 is provided below the base member 13. The porous chuck 17 comprises an alumina chuck table 18 and a porous alumina chuck 19.

[0027] The chuck table 18 is fastened to the base member 13 via bolts B2. This allows the rotational driving force input to the polishing head 10 to be transmitted to the porous chuck 17 via the base member 13.

[0028] The chuck 19 is embedded in the underside of the chuck table 18. The chuck 19 is connected to a vacuum source and a cooling water source (not shown) via line 18a. By activating the vacuum source, the workpiece W is held by suction on the holding surface 17a of the porous chuck 17. The cooling water supplied from the cooling water source is temperature-controlled to approximately room temperature, and the chuck 19 is cooled by passing the water through it after polishing.

[0029] In this way, the polishing head 10 holds the back surface of the workpiece W by suction to the chuck 19, and the front surface of the workpiece W is pressed against the polishing pad 5. As the first airbag 15 and the second airbag 16 inflate, a load is transmitted to the workpiece W, and the workpiece W is polished so that the shape of the holding surface 17a, which serves as the polishing surface, is transferred to it (back surface reference polishing). The holding surface 17a is set to a flatness of approximately 1 μm or less by lapping.

[0030] Next, a procedure for adjusting the load applied to the workpiece W by the first airbag 15 or the second airbag 16 will be described.

[0031] First, as shown in Figure 5(a), with the load from the first airbag 15 (hereinafter referred to as "normal load"), a convex pressure distribution is obtained in which the pressure is high near the center of the workpiece W and gradually decreases from the center to the outer circumference of the workpiece W. Since such a pressure distribution with a normal load is formed almost uniformly in the circumferential direction of the workpiece W, it is not suitable for polishing a workpiece W that has tilted after polishing due to crystal orientation or has an uneven initial film thickness to a nearly uniform thickness.

[0032] The pressure distribution acting on the workpiece W can be changed by adjusting the air pressure supplied to the second airbags 16A to 16D. Figures 6(a) to (i) are images showing the pressure acting on the workpiece W when the second airbags 16A to 16D are inflated and deflated while the first airbag 15 is deflated, using the Nitta Corporation surface pressure distribution measurement system "I-SCAN". Brighter areas indicate stronger pressure. Note that the images in Figures 6(a) to (i) show the pressure distribution acting on the workpiece W as viewed from the bottom, and the positive and negative directions of the X-axis are reversed compared to Figure 4.

[0033] Figure 6(a) shows the pressure acting on the workpiece W when air at a pressure of 8.5 psi is supplied to the second airbags 16C and 16D, respectively. Figure 6(b) shows the pressure acting on the workpiece W when air at a pressure of 12 psi is supplied to the second airbag 16C. Figure 6(c) shows the pressure acting on the workpiece W when air at a pressure of 8.5 psi is supplied to the second airbags 16B and 16C, respectively. Figure 6(d) shows the pressure acting on the workpiece W when air at a pressure of 12 psi is supplied to the second airbag 16D. Figure 6(e) shows the pressure acting on the workpiece W when air at a pressure of 12 psi is supplied to any of the second airbags 16A to 16D. Figure 6(f) shows the pressure acting on the workpiece W when no air is supplied, Figure 6(g) shows the pressure acting on the workpiece W when air at a pressure of 12 psi is supplied to the second airbag 16B, Figure 6(h) shows the pressure acting on the workpiece W when air at a pressure of 8.5 psi is supplied to the second airbags 16A and 16D respectively, Figure 6(i) shows the pressure acting on the workpiece W when air at a pressure of 8.5 psi is supplied to the second airbags 16A and 16B respectively.

[0034] As shown in Figures 6(b), (d), (f), and (h), when any one of the second airbags 16A to 16D is pressurized, the pressure acting directly below and around the pressurized second airbag 16A to 16D increases.

[0035] Furthermore, as shown in Figures 6(a), (c), (g), and (i), when two adjacent second airbags 16A to 16D are pressurized, the pressure acting directly below and around the two pressurized second airbags 16A to 16D, as well as the pressure acting between them, increases.

[0036] In this way, when the pressure distribution is moved in the circumferential direction of the workpiece W, as shown in Figure 7, the pressure F to be applied to the peak position P is vector-decomposed according to the coordinates of the peak position P where the pressure distribution in the circumferential direction of the workpiece W is maximum, and the pressure of the air to be supplied to the two adjacent second airbags 16A to 16D on either side of the peak position P is calculated.

[0037] That is, as shown in Figure 7, when setting the peak position P between the second airbags 16C and 16D, if Θ is the angle between the line segment connecting the peak position P and the origin O and the X-axis, then the pressure applied to the second airbag 16C is set to FsinΘ and the pressure applied to the second airbag 16D is set to FcosΘ. For example, if the angle Θ is set to 60 degrees and the pressure applied to the peak position P is set to 12 psi, then the air pressure supplied to the second airbag 16C is set to 10.4 psi and the air pressure supplied to the second airbag 16D is set to 6 psi.

[0038] In this way, as shown in Figure 5(b), the load from the second airbag 16 (hereinafter referred to as "partial load") yields a pressure distribution with a different shape than that under normal load. That is, the pressure distribution under partial load is formed non-uniformly in the circumferential direction of the workpiece W. As a result, by combining normal load and partial load, an appropriate pressure distribution can be set according to the crystal orientation and initial film thickness of the workpiece W, and a workpiece W with a substantially uniform film thickness after polishing can be obtained.

[0039] Since the second airbag 16 is housed within the first airbag 15, when the second airbag 16 is inflated while the first airbag 15 is inflated, the air pressure supplied to the second airbag 16 is set to be higher than the air pressure supplied to the first airbag 15.

[0040] Specifically, if Pall is the pressure of the air supplied to the first airbag 15, Sw is the area of ​​the workpiece W, Sa is the area of ​​the first airbag 15, and WP is the pressure at which the porous chuck 17 pressurizes the workpiece W, then the air pressure Pz supplied to the second airbag 16 is set such that Pz > Pall = (Sw / Sa) * WP.

[0041] Furthermore, the combination of normal load and partial load can be simultaneous or sequential. For example, the area around the orientation flat OF of the workpiece W becomes a singularity, and a phenomenon called discontinuous increase in material removal (sagging) may occur during grinding and polishing. Therefore, after normal polishing in which only the first airbag 15 is inflated to polish the workpiece W, the first airbag 15 is deflated, and then the second airbags 16B to 16D are inflated in sequence to polish the workpiece W excluding the area around the orientation flat OF. By polishing the entire surface of the workpiece W excluding the area around the orientation flat OF, sagging around the orientation flat OF can be eliminated. [Examples]

[0042] Next, we will describe the case where CMP polishing is performed on a workpiece W made of LiTaO3 (lithium tantalate) with a normal load (Comparative Example 1), and the case where CMP polishing is performed using a combination of normal load and partial load (Examples 1 and 2).

[0043] Table 1 shows the polishing conditions for Comparative Example 1 and Examples 1 and 2. Figure 8(a) shows the distribution of polishing removal amount on the X-axis (Y-coordinate: 0) for Comparative Example 1 and Examples 1 and 2, and Figure 8(b) shows the distribution of polishing removal amount on the Y-axis (X-coordinate: 0). In Table 1, "Zone 3" and "Zone 4" correspond to the second airbags 16C and 16D, respectively. [Table 1]

[0044] As shown in Figures 8(a) and (b), in Comparative Example 1, the amount of material removed by polishing in the negative X-coordinate region (especially below -25 mm) is relatively larger than the amount of material removed by polishing in the positive X-coordinate region, and the amount of material removed by polishing in the negative Y-coordinate region (especially below -25 mm) is relatively larger than the amount of material removed by polishing in the positive Y-coordinate region. This indicates that there is a bias in the amount of material removed by polishing within the W-plane of the workpiece.

[0045] On the other hand, in Example 1, by applying partial loads from the second airbags 16C and 16D in addition to the normal load from the first airbag 15, the amount of material removed by polishing in the region where the X coordinate is positive and the amount of material removed by polishing in the region where the Y coordinate is positive are increased, and it can be seen that the unevenness of the amount of material removed by polishing within the surface of the workpiece W is mitigated.

[0046] Furthermore, in Example 2, by further increasing the pressure of the air supplied to the second airbags 16C and 16D, the amount of polishing removed in the positive X-coordinate region and the amount of polishing removed in the positive Y-coordinate region are further increased. As a result, the amount of polishing removed in the positive X-coordinate region is relatively larger than the amount of polishing removed in the negative X-coordinate region, and the amount of polishing removed in the positive Y-coordinate region is relatively larger than the amount of polishing removed in the negative Y-coordinate region. Therefore, the bias in the amount of polishing removed within the W-plane of the workpiece is in contrast to that of Comparative Example 1.

[0047] Next, we will describe the case where CMP polishing is performed on a workpiece W made of SiC (silicon carbide) with a normal load (Comparative Example 2), and the case where CMP polishing is performed using a combination of normal load and partial load (Examples 3 and 4).

[0048] Table 2 shows the polishing conditions for Comparative Example 2 and Examples 3 and 4. Figure 9(a) shows the distribution of polishing removal amount on the X axis (Y coordinate: 0) for Comparative Example 2 and Examples 3 and 4, and Figure 9(b) shows the distribution of polishing removal amount on the Y axis (X coordinate: 0). Note that "Zone 4" in Table 1 corresponds to the second airbag 16D. [Table 2]

[0049] As shown in Figures 9(a) and (b), in Comparative Example 2, the amount of material removed by polishing in the negative X-coordinate region tends to be relatively larger than the amount removed by polishing in the positive X-coordinate region, indicating a bias in the amount of material removed by polishing within the W-plane of the workpiece.

[0050] On the other hand, in Example 3, by applying a partial load from the second airbag 16D in addition to the normal load from the first airbag 15, it can be seen that the amount of material removed by polishing increases in the region where the X coordinate is positive, and the unevenness of the amount of material removed by polishing within the surface of the workpiece W is mitigated.

[0051] Furthermore, in Example 4, by further increasing the pressure of the air supplied to the second airbag 16D, the amount of polishing removed in the positive X-coordinate region increases further, and the amount of polishing removed in the positive X-coordinate region tends to be relatively larger than the amount of polishing removed in the negative X-coordinate region. This shows that the bias in the amount of polishing removed within the workpiece W surface is in contrast to that of Comparative Example 2.

[0052] Next, we will describe the case in which the workpiece W, made of LiTaO3, is partially pressurized in stages to improve the sagging around the orientation flat OF (Example 5). The polishing conditions in Example 5 are shown in Table 3. In Table 3, "Zone 1" corresponds to the first airbag 16A, "Zone 2" corresponds to the first airbag 16B, "Zone 3" corresponds to the first airbag 16C, and "Zone 4" corresponds to the first airbag 16D. [Table 3]

[0053] Figure 10(a) shows the thickness of the workpiece W on the X-axis (Y-coordinate: 0) in each process, and Figure 10(b) shows the thickness of the workpiece W on the Y-axis (X-coordinate: 0) in each process. Furthermore, Figure 11(a) shows the distribution of polishing removal amount on the X-axis (Y-coordinate: 0) in each process, and Figure 11(b) shows the distribution of polishing removal amount on the Y-axis (X-coordinate: 0) in each process. Figure 12 is a graph showing the variation in thickness within the surface of the workpiece W in each process.

[0054] In Figures 10(a), (b), and 12, "Before Polishing" indicates the workpiece W before CMP polishing under normal load. As shown in Figure 10(b), it can be seen that sagging occurs around the orientation flat OF (Y coordinate: -50 mm or less), where the thickness of the workpiece W is significantly reduced. Furthermore, as shown in Figure 12, it can be seen that there is a thickness variation of approximately 0.34 μm within the surface of the workpiece W.

[0055] For such a workpiece W, first, only the first airbag 15 is inflated to polish the workpiece W (normal polishing). As shown in Figures 10(a) and (b), the workpiece W after normal polishing is polished to a concave shape, with the thinnest point near the center and gradually becoming thicker towards the outer edge. Also, as shown in Figures 11(a) and (b), the amount of material removed during normal polishing is greatest near the center and gradually decreases towards the outer edge. However, as shown in Figure 12, there is no significant change in the thickness variation within the surface of the workpiece W before and after normal polishing.

[0056] Next, after contracting the first airbag 15, the second airbags 16B to 16D are inflated in order to perform partial polishing (partial polishing 1) on the entire surface of the work W excluding the periphery of the orifice OF. In partial polishing 1, as shown in FIGS. 11(a) and 11(b), on the Y-axis, the periphery of the orifice OF is hardly polished, and it can be seen that the polishing removal amount in the region extending from the middle to the periphery of the work W (X < -about 25 mm and about 25 mm < X, about 25 mm < Y) is significantly larger than that near the center of the work W. As a result, as shown in FIGS. 10(a) and 10(b), after partial polishing 1, the entire surface of the work W excluding the periphery of the orifice OF is polished, and the concave shape of the work W is alleviated. Further, as shown in FIG. 12, it can be seen that the thickness variation within the surface of the work W is improved to 0.25 μm or less.

[0057] In this embodiment, after partial pressurization 1, a second-stage partial pressurization (partial polishing 2) is performed in which the second airbags 16A to 16D are inflated in order to further polish the work W. Partial polishing 2 is for improving the concave shape generated by normal polishing to form the work W substantially flat, and may be omitted when the polishing removal amount in normal polishing is small and the concave of the work W after normal polishing is shallow.

[0058] In partial polishing 2, as shown in FIGS. 11(a) and 11(b), it can be seen that the polishing removal amount in the region extending from the middle to the periphery of the work W (X < -about 25 mm and about 25 mm < X, Y < -about 25 mm and about 25 mm < Y) is significantly larger than that near the center of the work W. As a result, as shown in FIGS.  10(a) and 10(b), after passing through partial polishing 2, the concave shape of the work W is further alleviated. Further, as shown in FIG. 12, the thickness variation within the surface of the work W is further improved to 0.2 μm or less.

[0059] Thus, the CMP apparatus 1 according to this embodiment is a polishing apparatus that polishes a workpiece W held in a polishing head 10 by pressing it against a polishing pad 5 on a platen 2, and comprises a chuck 19 capable of holding the workpiece W, second airbags 16A to 16D arranged in parallel along the circumferential direction of the chuck 19 and capable of being inflated by air to press a part of the workpiece W toward the polishing pad 5, and a controller 6 capable of adjusting the pressure of the air supplied to the second airbags 16A to 16D.

[0060] With this configuration, the pressure distribution acting on the workpiece W can be freely adjusted in the circumferential direction of the workpiece W by inflating and deflating the second airbags 16A to 16D respectively. This allows the pressure distribution to be adjusted in the circumferential direction of the workpiece W, taking into account the crystal orientation and non-uniform initial film thickness of the workpiece W. By applying different polishing pressures to the workpiece W within the polishing surface, the workpiece W can be polished to a flat surface with high precision.

[0061] Furthermore, the CMP apparatus 1 according to this embodiment further includes a first airbag 15 provided around the entire circumference of the chuck 19, which inflates with air to press the entire surface of the workpiece W toward the polishing pad 5, and the second airbags 16A to 16D are housed within the first airbag 15.

[0062] With this configuration, the second airbags 16A to 16D are arranged so as to overlap the first airbag 15 when viewed from above. This allows for easy adjustment of the pressure distribution acting on the workpiece W by combining the uniform pressure distribution in the circumferential direction of the workpiece W provided by the first airbag 15 with the non-uniform pressure distribution in the circumferential direction of the workpiece W provided by the second airbags 16A to 16D.

[0063] Furthermore, the present invention can be modified in various ways other than those described above, as long as it does not deviate from the spirit of the invention, and it goes without saying that the present invention extends to such modified forms.

[0064] In the above-described embodiment, a CMP device 1 was described as an example, comprising a first airbag 15 that pressurizes the workpiece W with a substantially uniform pressure distribution in the circumferential direction, and second airbags 16A to 16D that pressurize the workpiece W with a non-uniform pressure distribution in the circumferential direction. However, for example, instead of the second airbags 16A to 16D, the first airbag 15 may be divided into multiple air chambers, and all air chambers may be inflated when pressurizing the workpiece W with a substantially uniform pressure distribution in the circumferential direction, and at least one air chamber may be inflated when pressurizing the workpiece W with a non-uniform pressure distribution in the circumferential direction. [Explanation of symbols]

[0065] 1:CMP equipment 2: Platen 3: (Platen's) axis of rotation 4: Motor 5: Polishing pad 6: Controller 10: Polishing head 10a: Rotation axis (of the polishing head) 11: Head body 12: Rotation transmission section 13: Base component 14: Plate holder 15: First airbag (overall pressure area) 16, 16A~16D: Second airbag (partial compression section) 17: Porous Chuck 17a: Holding surface 18: Chuck Table 19: Chuck W: Work

Claims

[Claim 1] A polishing device that polishes a workpiece held in a polishing head by pressing it against a polishing pad on a platen, A chuck capable of holding the workpiece on the holding surface which serves as the polishing surface, Multiple partial pressing sections are arranged in parallel along the circumferential direction of the chuck, and are expanded by air to form a non-uniform pressure distribution within the polishing surface that acts on the entire surface of the workpiece via the chuck, thereby pressing the workpiece toward the polishing pad with a non-uniform pressure distribution in the circumferential direction of the workpiece. A controller that allows for adjustment of the air pressure supplied to each individual pressing section, A total pressing section is provided around the entire circumference of the chuck, which expands with air and acts on the entire surface of the workpiece via the chuck, forming a uniform pressure distribution within the polishing surface in the circumferential direction of the workpiece, and pressing the entire surface of the workpiece toward the polishing pad with a uniform pressure distribution in the circumferential direction of the workpiece. Equipped with, The polishing apparatus is characterized in that the partial pressing portion is housed within the overall pressing portion.

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