Method for manufacturing a holding device

Abstract

To provide a method for manufacturing a holding device which can suppress occurrence of particles.SOLUTION: A method for manufacturing an electrostatic chuck 1 having a ceramic member 10 formed with a seal band 13 and a mesa 14 for holding a semiconductor wafer W includes: a preparation step P1 of preparing the ceramic member 10; a dummy mesa formation step P2 of forming a dummy mesa 41 and a dummy seal band 42 having top faces 41a and 42a, and a dummy recess 43 having a bottom surface 43a, on an upper surface 17 of the ceramic member 10; a dummy mesa removing and polishing step P3 of polishing the dummy mesa 41 and the dummy seal band 42, and removing at least a part of the dummy mesa 41 and the dummy seal band 42; and a mesa-seal band formation step of forming the seal band 13 and the mesa 14 at a position where the dummy mesa 41 and the dummy seal band 42 are formed, after the dummy mesa removing and polishing step P3.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a holding device that holds an object.

Background Art

[0002] As a document related to a method for manufacturing a holding device, Patent Document 1 discloses a method for manufacturing an electrostatic chuck that holds a wafer with a plate-shaped ceramic body. And in the method for manufacturing the electrostatic chuck disclosed in this Patent Document 1, the mounting surface of the wafer on the plate-shaped ceramic body is polished.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, by polishing the mounting surface of the wafer, there is a risk of cracks occurring on the mounting surface of the wafer. Then, when the wafer is placed on the mounting surface for processing, there is a risk of particles being generated where a part of the plate-shaped ceramic body peels off from the crack part.

[0005] Therefore, the present disclosure has been made to solve the above-described problems, and an object thereof is to provide a method for manufacturing a holding device capable of suppressing the generation of particles.

Means for Solving the Problems

[0006] One aspect of the present disclosure made to solve the above problems is a method for manufacturing a holding device having a ceramic plate-shaped member formed with a convex portion for holding an object, the method including: a preparation step of preparing the ceramic plate-shaped member; a temporary convex portion forming step of forming a temporary convex portion having a top surface and a temporary concave portion having a bottom surface on one surface of the ceramic plate-shaped member; a temporary convex portion polishing step of polishing the temporary convex portion from the top surface side toward the bottom surface side to remove at least a part of the temporary convex portion; and a convex portion forming step of forming the convex portion at a position where the temporary convex portion was formed after performing the temporary convex portion polishing step.

[0007] According to this aspect, in the method for manufacturing a holding device, by performing the temporary convex portion forming step and the temporary convex portion polishing step, cracks existing on one surface of the ceramic plate-shaped member can be removed. At this time, since the area to be polished in the temporary convex portion polishing step is reduced by previously performing the temporary convex portion forming step, in the temporary convex portion polishing step, the temporary convex portion can be polished and removed under polishing conditions that cause little damage to the surface to be polished without taking much time, so that the occurrence of cracks can be suppressed. Therefore, even in the ceramic plate-shaped member formed by performing the convex portion forming step thereafter, the occurrence of cracks that can cause particles can be suppressed on one surface thereof. Accordingly, in the holding device, the generation of particles on one surface of the ceramic plate-shaped member can be suppressed. Note that the "polishing conditions that cause little damage to the surface to be polished" are, for example, conditions in which the size of the abrasive grains of the abrasive, the polishing speed (the rotational speed of the polishing tool (such as a polishing head or a polishing table)), the polishing load (the load applied from the polishing tool to the surface to be polished), etc. are reduced.

[0008] In the above aspect, it is preferable that the preparation step is a step of preparing the ceramic plate-shaped member to which a base member is joined.

[0009] According to this aspect, in the holding device having a base member, the generation of particles can be suppressed.

[0010] In the above aspect, in the temporary convex portion forming step, it is preferable that the width of the temporary convex portion is made larger than the width of the convex portion.

[0011] According to this aspect, even if the position where the convex portion is formed in the convex portion forming step is slightly deviated from the target position, the target dimensions of the convex portion can be ensured.

[0012] In the above aspect, it is preferable that the preparation step includes a one-sided polishing step of polishing one surface of the ceramic plate-like member.

[0013] According to this aspect, in the preparation step, by previously polishing one surface of the ceramic plate-like member in the one-sided polishing step, the shape of the ceramic plate-like member can be adjusted, or the flatness of one surface of the ceramic plate-like member can be improved. And at this time, even if cracks occur when polishing in the one-sided polishing step, these cracks can be removed in the subsequent temporary convex portion forming step or temporary convex portion polishing step. Therefore, a ceramic plate-like member without cracks can be formed while adjusting the shape of the ceramic plate-like member or improving the flatness of one surface of the ceramic plate-like member.

[0014] In the above aspect, it is preferable that the preparation step includes a bonding step of bonding the base member to the other surface of the ceramic plate-like member opposite to the one surface, and a flatness adjustment polishing step of polishing the one surface of the ceramic plate-like member to which the base member is bonded to adjust the flatness.

[0015] According to this aspect, even if the flatness of one surface of the ceramic plate-like member to which the base member is joined by performing the joining process changes, the flatness can be adjusted and improved in the flatness adjustment polishing process. And even if cracks occur when polishing in the flatness adjustment polishing process, these cracks can be removed in the subsequent temporary convex portion forming process and temporary convex portion polishing process. Therefore, it is possible to form a ceramic plate-like member without cracks while improving the flatness of one surface of the ceramic plate-like member.

[0016] In the above aspect, it is preferable that the size of the abrasive grains of the abrasive used in the temporary convex portion polishing process is smaller than the size of the abrasive grains of the abrasive used in the flatness adjustment polishing process.

[0017] According to this aspect, in the temporary convex portion polishing process, polishing is performed under polishing conditions that cause little damage to the surface to be polished, so the occurrence of cracks can be suppressed. On the other hand, in the flatness adjustment polishing process, by performing polishing under polishing conditions that emphasize polishing efficiency, it is possible to surely improve the flatness of one surface of the ceramic plate-like member in a short time. Note that "polishing conditions that emphasize polishing efficiency" are conditions that emphasize efficiently polishing the surface to be polished, for example, conditions in which the size of the abrasive grains of the abrasive, the polishing speed, the polishing load, etc. are increased.

[0018] In the above aspect, it is preferable that a part of the temporary convex portion is left in the temporary convex portion polishing process.

[0019] According to this aspect, even if not all of the temporary convex portion is removed, for example, when the cracks are removed, the temporary convex portion polishing process can be terminated, so the manufacturing time of the holding device can be shortened.

[0020] In the above aspect, it is preferable that all of the temporary convex portion is removed in the temporary convex portion polishing process.

[0021] According to this aspect, the cracks existing in the temporary convex portion can be surely removed.

[0022] In the above aspect, it is preferable that the ceramic plate-like member includes at least one of an adsorption electrode, a heater electrode, and a high-frequency electrode.

[0023] According to this aspect, generation of particles on one surface of the ceramic plate-like member provided with electrodes such as an adsorption electrode, a heater electrode, and a high-frequency electrode can be suppressed.

Advantages of the Invention

[0024] According to the manufacturing method of the holding device of the present disclosure, a holding device capable of suppressing generation of particles can be manufactured.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0026] Hereinafter, embodiments of the manufacturing method of the holding device of the present disclosure will be described. In the following embodiments, the case where the holding device of the present disclosure is applied to the electrostatic chuck 1 for holding the semiconductor wafer W will be described.

[0027] <Configuration of Electrostatic Chuck> First, the configuration of the electrostatic chuck 1 of the present embodiment will be described.

[0028] The electrostatic chuck 1 is a device that adsorbs and holds the semiconductor wafer W (object) by electrostatic attraction, and is used, for example, to fix the semiconductor wafer W in the vacuum chamber of a semiconductor manufacturing apparatus. As shown in FIG. 1, the electrostatic chuck 1 includes a ceramic member 10, a base member 20, and a bonding layer 30 that bonds the ceramic member 10 and the base member 20. Note that the electrostatic chuck 1 is an example of the "holding device" of the present disclosure. Further, the ceramic member 10 is an example of the "ceramic plate-like member" of the present disclosure.

[0029] In the following description, for convenience of explanation, the XYZ axes are defined as shown in FIG. 1. Here, the Z axis is the axis in the axial direction (the vertical direction in FIG. 1) of the electrostatic chuck 1, and the X axis and the Y axis are the axes in the radial direction of the electrostatic chuck 1.

[0030] As shown in Fig. 1, the ceramic member 10 is a disk-shaped member formed of ceramics. Various ceramics can be used as the ceramics, but from the viewpoints of strength, wear resistance, plasma resistance, etc., for example, ceramics mainly composed of aluminum oxide (alumina, Al2O3) or aluminum nitride (AlN) are preferably used. Here, the main component means the component with the highest content ratio (for example, the component with a volume content ratio of 90 vol% or more).

[0031] Also, the diameter of the ceramic member 10 is, for example, about 150 to 300 mm. The thickness of the ceramic member 10 is, for example, about 2 to 6 mm. The thermal conductivity of the ceramic member 10 is desirably in the range of 10 to 50 W / mK (more preferably, 18 to 30 W / mK).

[0032] As shown in Figs. 1 and 2, the ceramic member 10 includes a holding surface 11 for holding the semiconductor wafer W and a lower surface 12 provided on the side opposite to the holding surface 11 in the thickness direction (Z-axis direction, up and down direction) of the ceramic member 10. Note that the holding surface 11 is an example of "one surface" of the present disclosure. Also, the lower surface 12 is an example of "the other surface" of the present disclosure.

[0033] The holding surface 11 of the ceramic member 10 has an uneven shape. Specifically, as shown in Figs. 2 and 3, an annular seal band 13 (annular convex portion) is formed near the outer edge of the holding surface 11, and a plurality of independent columnar mesas 14 (convex portions) are formed inside the seal band 13. In this way, a seal band 13 is formed on the holding surface 11 so as to surround all of the plurality of mesas 14. The shape of the cross section (XZ cross section) of the seal band 13 is substantially rectangular as shown in Fig. 2. The height Hs1 (dimension in the Z-axis direction) of the seal band 13 is, for example, about 10 μm to 20 μm. Also, the width δs1 (dimension in the X-axis direction) of the seal band 13 is, for example, about 0.5 mm to 5.0 mm. Note that the seal band 13 and the mesa 14 are each an example of the "convex portion" of the present disclosure.

[0034] As shown in FIG. 3, each mesa 14 is substantially circular in a Z-axis direction view (plan view) and is arranged at substantially equal intervals. Further, as shown in FIG. 2, the shape of the cross section (XZ cross section) of each mesa 14 is substantially rectangular. The height Hm1 of the mesa 14 is substantially the same as the height Hs1 of the seal band 13 and is, for example, about 10 to 20 μm. Further, the width δm1 of the mesa 14 (the maximum diameter of the mesa 14 in the Z-axis direction view) is, for example, about 0.5 to 1.5 mm. Note that, inside the seal band 13 on the holding surface 11 of the ceramic member 10, the portion where the mesa 14 is not formed is a recess 15.

[0035] Then, the semiconductor wafer W is supported by the seal band 13 on the holding surface 11 of the ceramic member 10 and a plurality of mesas 14, and is held by the electrostatic chuck 1. In a state where the semiconductor wafer W is held by the electrostatic chuck 1, a space S exists between the surface (lower surface) of the semiconductor wafer W and the holding surface 11 of the ceramic member 10 (specifically, the recess 15 of the holding surface 11) (see FIG. 2). An inert gas (for example, helium gas) is supplied to this space S through a gas hole (not shown).

[0036] Further, as shown in FIG. 2, the ceramic member 10 includes an electrode 16. Although not clearly shown in FIG. 2 for convenience of explanation, the ceramic member 10 includes at least one of a suction electrode, a heater electrode, and a high-frequency electrode as the electrode 16.

[0037] As shown in FIG. 1, the base member 20 is formed in a columnar shape. This base member 20 is preferably a metal member formed of a metal (for example, aluminum, an aluminum alloy, etc.), but may be formed of other than metal.

[0038] Then, as shown in FIGS. 1 to 3, the base member 20 includes an upper surface 21 and a lower surface 22 provided on the side opposite to the upper surface 21 in the thickness direction of the base member 20 (i.e., the Z-axis direction). The upper surface 21 of the base member 20 is thermally connected to the lower surface 12 of the ceramic member 10 via the bonding layer 30.

[0039] The diameter of the base member 20 is, for example, about 180 mm to 350 mm. The thickness of the base member 20 (dimension in the Z-axis direction) is, for example, about 20 mm to 50 mm. The thermal conductivity of the base member 20 (assuming aluminum) is greater than that of the ceramic member 10 and is desirably in the range of 180 to 250 W / mK (preferably about 230 W / mK).

[0040] The bonding layer 30 is disposed between the lower surface 12 of the ceramic member 10 and the base member 20 and joins the ceramic member 10 and the base member 20. Through this bonding layer 30, the lower surface 12 of the ceramic member 10 and the base member 20 are thermally connected. The bonding layer 30 is composed of an adhesive such as a silicone-based resin, an acrylic-based resin, or an epoxy-based resin. The thickness of the bonding layer 30 (dimension in the Z-axis direction) is, for example, about 0.1 to 1.0 mm. The thermal conductivity of the bonding layer 30 is, for example, 1.0 W / mK. The thermal conductivity of the bonding layer 30 (assuming a silicone-based resin) is desirably in the range of 0.1 to 2.0 W / mK (preferably 0.5 to 1.5 W / mK).

[0041] <Method for manufacturing an electrostatic chuck> Next, a method for manufacturing the electrostatic chuck 1 will be described.

[0042] In the method for manufacturing the electrostatic chuck 1 of the present embodiment, as shown in FIG. 4, in order of steps, there are a preparation step P1, a dummy mesa-dummy seal band forming step P2 (hereinafter simply referred to as "dummy mesa forming step P2"), a dummy mesa-dummy seal band removing and polishing step P3 (hereinafter simply referred to as "dummy mesa removing and polishing step P3"), and a mesa-seal band forming step P4.

[0043] Note that the dummy mesa formation step P2 is an example of the "temporary convex portion formation step" of the present disclosure. Further, the dummy mesa removal polishing step P3 is an example of the "temporary convex portion polishing step" of the present disclosure. Furthermore, the mesa / seal band formation step P4 is an example of the "convex portion formation step" of the present disclosure.

[0044] (Preparation Step) First, as the preparation step P1, a ceramic member 10 to which a base member 20 is joined is prepared. This preparation step P1 includes, in order of process, a primary polishing step P1a, a bonding step P1b, and a flat polishing step P1c.

[0045] Note that the primary polishing step P1a is an example of the "one-sided polishing step" of the present disclosure. Further, the bonding step P1b is an example of the "bonding step" of the present disclosure. Furthermore, the flat polishing step P1c is an example of the "flatness adjustment polishing step" of the present disclosure.

[0046] Therefore, first, as the primary polishing step P1a, the upper surface 17 of the ceramic member 10 is polished. Here, the upper surface 17 is the surface on the side where the holding surface 11 is formed later, and is a surface provided on the side opposite to the lower surface 12 in the thickness direction (Z-axis direction, vertical direction) of the ceramic member 10. As a method for polishing this upper surface 17, for example, a polishing method using a rotating grindstone, a polishing method by lapping, etc. can be considered. And thereby, as shown in FIG. 5, the upper surface 17 is polished and the flatness of the upper surface 17 is improved. However, at this time, on the upper surface 17, cracks CL are generated due to polishing. Note that the upper surface 17 is an example of the "one surface" of the present disclosure.

[0047] These cracks CL cause particles to be generated when the semiconductor wafer W is held by the electrostatic chuck 1 and processed. That is, a part of the holding surface 11 of the ceramic member 10 peels off from the crack CL portion, and this peeled-off portion becomes particles. Therefore, in the present embodiment, in the dummy mesa formation step P2 and the dummy mesa removal polishing step P3, which are steps described in detail later, a step for removing the cracks CL is performed.

[0048] After performing the primary polishing step P1a in this manner, as the bonding step P1b, as shown in FIG. 6, the base member 20 is bonded to the lower surface 12 of the ceramic member 10 via the bonding layer 30 to form a bonded body of the ceramic member 10 and the base member 20.

[0049] Next, as the flat polishing step P1c, the upper surface 17 of the ceramic member 10 to which the base member 20 is bonded is polished to adjust the flatness of the upper surface 17. And thereby, the flatness of the upper surface 17 (specifically, the later holding surface 11) is improved. However, at this time, as shown in FIG. 7, on the upper surface 17, new cracks CL are generated by being polished.

[0050] And after performing the preparation step P1 in this manner, in this embodiment, the dummy mesa forming step P2 and the dummy mesa removal polishing step P3 are performed to remove the cracks CL.

[0051] (Dummy Mesa Forming Step) First, as the dummy mesa forming step P2, as shown in FIG. 8, on the upper surface 17 of the ceramic member 10, a dummy mesa 41 having a top surface 41a and a dummy seal band 42 having a top surface 42a are formed by blasting. Also, at this time, a dummy recess 43 having a bottom surface 43a is formed on the upper surface 17.

[0052] Note that the dummy mesa 41 and the dummy seal band 42 are each an example of the "temporary convex portion" of the present disclosure. Also, the dummy recess 43 is an example of the "temporary concave portion" of the present disclosure.

[0053] A plurality of dummy mesas 41 are formed. As shown by the dashed line in FIG. 12 to be described later, they are substantially circular in a Z-axis direction view (plan view) and are arranged at substantially equal intervals. As shown in FIG. 8, the cross-sectional shape (XZ cross-section) of each dummy mesa 41 is substantially rectangular. Also, the dummy seal band 42 is formed annularly near the outer edge of the upper surface 17. In this way, a dummy seal band 42 is formed on the upper surface 17 so as to surround all of the plurality of dummy mesas 41. As shown in FIG. 8, the cross-sectional shape (XZ cross-section) of the dummy seal band 42 is substantially rectangular.

[0054] And in this way, by forming the dummy mesa 41 and the dummy seal band 42 by blasting, on the upper surface 17, cracks CL existing in the portion to be removed by blasting, that is, the portion other than the dummy mesa 41 and the portion other than the dummy seal band 42 are removed.

[0055] Here, as shown in FIG. 9, the width δm0 of the dummy mesa 41 is made larger than the width δm1 of the mesa 14, and the width δs0 of the dummy seal band 42 is made larger than the width δs1 of the seal band 13. For example, while the width δm1 of the mesa 14 is 1 mm, the width δm0 of the dummy mesa 41 is 1.4 mm. Also, while the width δs1 of the seal band 13 is 3.0 mm, the width δs0 of the dummy seal band 42 is 3.4 mm.

[0056] Also, in the dummy mesa forming step P2, as shown in FIG. 9, the height Hm0 of the dummy mesa 41 and the height Hs0 of the dummy seal band 42 are made larger than the height HC (depth) of the crack CL (crushed layer) existing on the upper surface 17 of the ceramic member 10. For example, when the height HC of the crack CL is 5 μm to 10 μm, the height Hm0 of the dummy mesa 41 and the height Hs0 of the dummy seal band 42 are made 15 μm to 20 μm.

[0057] (Dummy Mesa Removal and Polishing Step) Next, as the dummy mesa removal and polishing step P3, as shown in FIG. 10, the dummy mesa 41 is polished and removed from its top surface 41a side toward its bottom surface 43a side, and the dummy seal band 42 is polished and removed from its top surface 42a side toward its bottom surface 43a side. As a result, the cracks CL existing in the dummy mesa 41 and the dummy seal band 42 are removed, so that all the cracks CL existing on the upper surface 17 are removed.

[0058] In the dummy mesa removal and polishing step P3, at least a part of the dummy mesa 41 (specifically, at least a part of each of the plurality of formed dummy mesas 41), and at least a part of the dummy seal band 42 may be removed. That is, as shown in FIG. 10, all of the dummy mesa 41 and the dummy seal band 42 may be removed, or the polishing may be stopped when the crack CL is removed, leaving a part of the dummy mesa 41 and the dummy seal band 42.

[0059] Also, in the present embodiment, since the dummy mesa forming step P2 is performed before the dummy mesa removal and polishing step P3, the area to be polished when performing the dummy mesa removal and polishing step P3 is small. Therefore, in the dummy mesa removal and polishing step P3, polishing may be performed under polishing conditions that cause little damage to the surface to be polished, so the size of the abrasive grains of the abrasive used is reduced. Therefore, the size of the abrasive grains of the abrasive used in the dummy mesa removal and polishing step P3 is made smaller than the size of the abrasive grains of the abrasive used in the flat polishing step P1c in the preparation step P1. And thereby, in the dummy mesa removal and polishing step P3, by performing polishing while reducing the damage to the upper surface 17, the generation of new cracks CL can be suppressed. For example, when the size of the abrasive grains of the abrasive used in the flat polishing step P1c is 30 μm, the size of the abrasive grains of the abrasive used in the dummy mesa removal and polishing step P3 is made 0.5 μm.

[0060] Also, since the top surface 41a of the dummy mesa 41 and the top surface 42a of the dummy seal band 42 are polished in the dummy mesa removal polishing step P3, the portion where the dummy mesa 41 and the dummy seal band 42 were formed on the top surface 17, or the portion where the dummy mesa 41 and the dummy seal band 42 partially remain on the top surface 17, becomes a super mirror surface state.

[0061] As a modification, after performing the dummy mesa removal polishing step P3, further polishing may be performed under polishing conditions that cause little damage to the surface to be polished, so that the top surface 17 is polished while preventing the crack CL from occurring.

[0062] (Mesa and Seal Band Forming Step) Next, after performing the dummy mesa removal polishing step P3, as the mesa and seal band forming step P4, as shown in FIG. 11, the seal band 13 and the mesa 14 are formed by blasting. At this time, the top surface 17 is shaved to form the holding surface 11. Also, at this time, as shown in FIG. 12, when the holding surface 11 of the ceramic member 10 is viewed in plan, the mesa 14 is formed so as to fit into the position where the dummy mesa 41 was formed, and the seal band 13 is formed so as to fit into the position where the dummy seal band 42 was formed.

[0063] Here, in the dummy mesa forming step P2, the width δm0 of the dummy mesa 41 was made larger than the width δm1 of the mesa 14, and the width δs0 of the dummy seal band 42 was made larger than δWs1 of the seal band 13. Therefore, the mesa 14 can be easily formed at the position where the dummy mesa 41 was formed, and the seal band 13 can be easily formed at the position where the dummy seal band 42 was formed. Thus, even if the positions where the seal band 13 and the mesa 14 are formed in the mesa and seal band forming step P4 deviate slightly from the target positions, the seal band 13 and the mesa 14 can be formed so as to fit into the positions where the dummy mesa 41 and the dummy seal band 42 were formed.

[0064] Also, as described above, by performing the dummy mesa removal polishing step P3, the portion where the dummy mesa 41 and the dummy seal band 42 were formed on the upper surface 17, or the portion where the dummy mesa 41 and the dummy seal band 42 partially remain on the upper surface 17, is in a super mirror finish state. Therefore, the top surface 14a of the mesa 14 formed at the position where the dummy mesa 41 was formed (or partially remains), and the top surface 13a of the seal band 13 formed at the position where the dummy seal band 42 was formed (or partially remains) can also be in a super mirror finish state.

[0065] Also, according to the remaining amounts of the dummy mesa 41 and the dummy seal band 42 after performing the dummy mesa removal polishing step P3, the processing conditions of the blasting process in the mesa-seal band forming step P4 are changed.

[0066] For example, when the height Hs1 of the seal band 13 and the height Hm1 of the mesa 14 are set to 20 μm, if all of the dummy mesa 41 and the dummy seal band 42 are removed and none remain after performing the dummy mesa removal polishing step P3, then in the mesa-seal band forming step P4, 20 μm is cut at the position corresponding to the concave portion 15 on the upper surface 17 by blasting to make the height Hs1 of the seal band 13 and the height Hs1 of the mesa 14 equal to 20 μm.

[0067] Also, when the height Hs1 of the seal band 13 and the height Hm1 of the mesa 14 are set to 20 μm, if 5 μm of the dummy mesa 41 and the dummy seal band 42 remain after performing the dummy mesa removal polishing step P3, then in the mesa-seal band forming step P4, 15 μm is cut at the position corresponding to the concave portion 15 on the upper surface 17 by blasting to make the height Hs1 of the seal band 13 and the height Hm1 of the mesa 14 equal to 20 μm.

[0068] <The effects of this embodiment> As described above, in this embodiment, in the manufacturing method of the electrostatic chuck 1, it includes a preparation step P1, a dummy mesa forming step P2, a dummy mesa removal polishing step P3, and a mesa-seal band forming step P4.

[0069] Thus, in the method for manufacturing the electrostatic chuck 1, by performing the dummy mesa formation step P2 and the dummy mesa removal and polishing step P3, the crack CL existing on the upper surface 17 of the ceramic member 10 (i.e., the surface on the side where the holding surface 11 is to be formed later) can be removed. At this time, since the area to be polished in the dummy mesa removal and polishing step P3 is reduced by previously performing the dummy mesa formation step P2, in the dummy mesa removal and polishing step P3, the dummy mesa 41 and the dummy seal band 42 can be polished and removed under polishing conditions with little damage to the surface to be polished without taking much time, so that the generation of the crack CL can be suppressed. Therefore, also in the ceramic member 10 formed by performing the mesa - seal band formation step P4 thereafter, the generation of the crack CL that can cause particles can be suppressed at the holding surface 11. Accordingly, in the electrostatic chuck 1, the generation of particles at the holding surface 11 of the ceramic member 10 can be suppressed.

[0070] Also, the preparation step P1 is a step of preparing the ceramic member 10 to which the base member 20 is joined. Thereby, in the electrostatic chuck 1 having the base member 20, the generation of particles can be suppressed.

[0071] Also, in the dummy mesa formation step P2, the width δm0 of the dummy mesa 41 is made larger than the width δm1 of the mesa 14, and the width δs0 of the dummy seal band 42 is made larger than the width δs1 of the seal band 13.

[0072] Thereby, even if the positions where the seal band 13 and the mesa 14 are formed in the mesa - seal band formation step P4 deviate somewhat from the target positions, the seal band 13 and the mesa 14 can be formed so as to fit into the positions where the dummy mesa 41 and the dummy seal band 42 are formed, and the target dimensions of the seal band 13 and the mesa 14 can be ensured.

[0073] In the dummy mesa formation step P2, the height Hm0 of the dummy mesa 41 and the height Hs0 of the dummy seal band 42 are made larger than the size of the crack CL present on the upper surface 17 of the ceramic member 10.

[0074] As a result, in the subsequent dummy mesa removal and polishing step P3, for the dummy mesa 41 and the dummy seal band 42, the size of the crack CL is polished respectively, and the crack CL present in the dummy mesa 41 and the dummy seal band 42 can be surely removed.

[0075] The preparation step P1 includes a primary polishing step P1a.

[0076] In this way, in the preparation step P1, by previously polishing the upper surface 17 of the ceramic member 10 in the primary polishing step P1a, the shape of the ceramic member 10 can be adjusted, or the flatness of the upper surface 17 of the ceramic member 10 can be improved. And at this time, even if a crack CL occurs when polishing in the primary polishing step P1a, this crack CL can be removed in the subsequent dummy mesa formation step P2 and dummy mesa removal and polishing step P3. Therefore, a ceramic member 10 without cracks CL can be formed while adjusting the shape of the ceramic member 10 and improving the flatness of the holding surface 11 of the ceramic member 10.

[0077] The preparation step P1 also includes a bonding step P1b and a flat polishing step P1c.

[0078] As a result, even if the flatness of the upper surface 17 of the ceramic member 10 joined with the base member 20 changes by performing the bonding step P1b, the flatness can be adjusted and improved in the flat polishing step P1c. And even if a crack CL occurs when polishing in the flat polishing step P1c, this crack CL can be removed in the subsequent dummy mesa formation step P2 and dummy mesa removal and polishing step P3. Therefore, a ceramic member 10 without cracks CL can be formed while improving the flatness of the holding surface 11 formed based on the upper surface 17 later.

[0079] Also, the size of the abrasive grains of the abrasive used in the dummy mesa removal polishing step P3 is made smaller than the size of the abrasive grains of the abrasive used in the flat polishing step P1c.

[0080] As a result, in the dummy mesa removal polishing step P3, polishing is performed under polishing conditions that cause little damage to the surface to be polished, so that the generation of cracks CL can be suppressed. On the other hand, in the flat polishing step P1c, by performing polishing under polishing conditions that emphasize polishing efficiency, the flatness of the upper surface 17 of the ceramic member 10 can be surely improved in a short time.

[0081] Also, in the dummy mesa removal polishing step P3, a part of the dummy mesa 41 and / or a part of the dummy seal band 42 are left.

[0082] As a result, even if not all of the dummy mesa 41 and the dummy seal band 42 are removed, for example, when the crack CL is removed, the dummy mesa removal polishing step P3 can be terminated, so that the manufacturing time of the electrostatic chuck 1 can be shortened.

[0083] Also, in the dummy mesa removal polishing step P3, all of the dummy mesa 41 and / or all of the dummy seal band 42 are removed.

[0084] As a result, the cracks CL existing in the dummy mesa 41 and the dummy seal band 42 can be surely removed.

[0085] Also, the ceramic member 10 includes, as the electrode 16, at least one of a suction electrode, a heater electrode, and a high-frequency electrode.

[0086] As a result, the generation of particles on the holding surface 11 of the ceramic member 10 including the electrode 16 such as a suction electrode, a heater electrode, and a high-frequency electrode can be suppressed.

[0087] Note that the above-described embodiments are merely illustrative and do not limit the present disclosure in any way. Of course, various improvements and modifications can be made without departing from the gist thereof.

[0088] For example, the preparation step P1 may include a primary polishing step P1a and a bonding step P1b, but not include a flat polishing step P1c.

[0089] Also, as the preparation step P1, a ceramic member 10 to which the base member 20 is not joined may be prepared. That is, in the preparation step P1, after only performing the primary polishing step P1a without performing the bonding step P1b and the flat polishing step P1c, the dummy mesa formation step P2, the dummy mesa removal polishing step P3, and the mesa / seal band formation step P4 may be performed, and then the bonding step P1b may be performed.

Explanation of Reference Numerals

[0090] 1 Electrostatic chuck 10 Ceramic member 11 Holding surface 12 Bottom surface 13 Seal band (annular convex portion) 13a Top surface 14 Mesa (convex portion) 14a Top surface 15 Concave portion 16 Electrode 17 Top surface 20 Base member 21 Top surface 22 Bottom surface 30 Bonding layer 41 Dummy mesa 41a Top surface 42 Dummy seal band 42a Top surface 43 Dummy concave portion 43a Bottom surface W Semiconductor wafer Hs0 Height of (dummy seal band) Hs1 Height of (seal band) Hm0 Height of (dummy mesa) Height of Hm1 (mesa) Height of HC (crack) Width of δs0 (dummy seal band) Width of δs1 (seal band) Width of δm0 (dummy mesa) Width of δm1 (mesa) S space P1 Preparation process P1a Primary grinding process P1b Bonding process P1c Flat grinding process P2 Dummy mesa formation process (dummy mesa·dummy seal band formation process) P3 Dummy mesa removal grinding process (dummy mesa·dummy seal band removal grinding process) P4 Mesa·seal band formation process CL Crack a region β region γ arrow

Claims

1. In a method for manufacturing a holding device having a ceramic plate-shaped member formed with convex portions for holding an object, a preparation step of preparing the ceramic plate-shaped member; a temporary convex portion forming step of forming a temporary convex portion having a top surface and a temporary concave portion having a bottom surface on one surface of the ceramic plate-shaped member; a temporary convex portion polishing step of polishing the temporary convex portion from the top surface side toward the bottom surface side to remove at least a part of the temporary convex portion; a convex portion forming step of forming the convex portion by blasting at the position where the temporary convex portion was formed after performing the temporary convex portion polishing step; having, A method for manufacturing a holding device, characterized by the above.

2. In the method for manufacturing a holding device according to Claim 1, the preparation step is a step of preparing the ceramic plate-shaped member to which a base member is joined, A method for manufacturing a holding device, characterized by the above.

3. In the method for manufacturing a holding device according to Claim 1 or 2, in the temporary convex portion forming step, making the width of the temporary convex portion larger than the width of the convex portion; A method for manufacturing a holding device, characterized by the above.

4. In the method for manufacturing a holding device according to any one of Claims 1 to 3, the preparation step includes a one-sided polishing step of polishing one surface of the ceramic plate-shaped member; A method for manufacturing a holding device, characterized by the above.

5. In the method for manufacturing a holding device according to Claim 2, the preparation step includes a joining step of joining the base member to the other surface of the ceramic plate-shaped member, which is opposite to the one surface; a flatness adjustment polishing step of polishing the one surface of the ceramic plate-shaped member to which the base member is joined to adjust the flatness; being included, A method for manufacturing a holding device, characterized by the above.

6. In the method for manufacturing a holding device according to Claim 5, making the grain size of the abrasive grains of the abrasive used in the temporary convex portion polishing step smaller than the grain size of the abrasive grains of the abrasive used in the flatness adjustment polishing step; A method for manufacturing a holding device, characterized by the above.

7. In the method for manufacturing a holding device according to any one of Claims 1 to 6, leaving a part of the temporary convex portion in the temporary convex portion polishing step; A method for manufacturing a holding device, characterized by the above.

8. In the method for manufacturing a holding device according to any one of Claims 1 to 6, removing all of the temporary convex portion in the temporary convex portion polishing step; A method for manufacturing a holding device, characterized by the above.

9. In the method for manufacturing a holding device according to any one of Claims 1 to 8, The ceramic plate-like member includes at least one of an adsorption electrode, a heater electrode, and a high-frequency electrode. A method for manufacturing a holding device, characterized thereby.

10. In a method for manufacturing a holding device having a ceramic plate-like member formed with a convex portion for holding an object, a preparation step of preparing the ceramic plate-like member to which a base member is joined; a temporary convex portion forming step of forming a temporary convex portion having a top surface and a temporary concave portion having a bottom surface on one surface of the ceramic plate-like member; a temporary convex portion polishing step of polishing the temporary convex portion from the top surface side toward the bottom surface side to remove at least a part of the temporary convex portion; a convex portion forming step of forming the convex portion at a position where the temporary convex portion is formed after the temporary convex portion polishing step; which has, In the preparation step, a joining step of joining the base member to the other surface of the ceramic plate-like member, which is opposite to the one surface; a flatness adjustment polishing step of polishing one surface of the ceramic plate-like member to which the base member is joined to adjust flatness; is included, A method for manufacturing a holding device, characterized thereby.

11. In a method for manufacturing a holding device having a ceramic plate-like member formed with a convex portion for holding an object, a preparation step of preparing the ceramic plate-like member to which a base member is joined; a temporary convex portion forming step of forming a temporary convex portion having a top surface and a temporary concave portion having a bottom surface on one surface of the ceramic plate-like member; a temporary convex portion polishing step of polishing the temporary convex portion from the top surface side toward the bottom surface side to remove at least a part of the temporary convex portion; a convex portion forming step of forming the convex portion at a position where the temporary convex portion is formed after the temporary convex portion polishing step; which has, In the preparation step, a joining step of joining the base member to the other surface of the ceramic plate-like member, which is opposite to the one surface; a flatness adjustment polishing step of polishing one surface of the ceramic plate-like member to which the base member is joined to adjust flatness; is included, The size of the abrasive grains of the abrasive used in the temporary convex portion polishing step is made smaller than the size of the abrasive grains of the abrasive used in the flatness adjustment polishing step. A method for manufacturing a holding device, characterized thereby.

12. In a method for manufacturing a holding device having a ceramic plate-like member formed with a convex portion for holding an object, a preparation step of preparing the ceramic plate-like member; A temporary convex portion forming step of forming a temporary convex portion having a top surface and a temporary concave portion having a bottom surface on one surface of the ceramic plate-like member; A temporary convex portion polishing step of polishing the temporary convex portion from the top surface side toward the bottom surface side to remove all of the temporary convex portion; A convex portion forming step of forming the convex portion at the position where the temporary convex portion was formed after performing the temporary convex portion polishing step; having; A method for manufacturing a holding device, characterized by the above.

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