CMP device

Abstract

To provide a CMP device which inhibits scattering of slurry during processing, increases an amount of the slurry to be recovered to improve utilization efficiency, and facilitates regeneration of the slurry.SOLUTION: A CMP device 10 presses one surface of a wafer W rotating integrally with a polishing head 13 to a rotating platen 12 and polishes the one surface of the wafer W with slurry supplied to a space between the wafer W and the platen 12. The CMP device 10 is provided with a slurry scattering prevention cover 46 which covers a periphery of the polishing head 13 from above.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a CMP apparatus, and more particularly to a CMP apparatus capable of suppressing the scattering of slurry when polishing a wafer by CMP. [Background technology]

[0002] BACKGROUND ART In the field of semiconductor manufacturing, chemical mechanical polishing (CMP) is known as a technique for planarizing the surface of semiconductor wafers (hereinafter referred to as "wafers") such as silicon wafers (see, for example, Patent Document 1).

[0003] As shown in FIG. 8, a conventional CMP apparatus includes a platen 101, a polishing head 102, a slurry nozzle 103, and other components arranged in a processing chamber 100. A wafer W to be polished (not shown) is attached to the polishing head 102. A retaining ring 104 and the wafer W rotate integrally with the polishing head 102. As the polishing head 102 rotates, it presses one surface of the wafer W against the platen 101, which is also rotating, with a predetermined pressure. The slurry nozzle 103 ejects slurry from its slurry ejection port 103a onto the platen 101, supplying the slurry between the platen 101 and the wafer W. The position at which the slurry is ejected from the slurry ejection port 103a of the slurry nozzle 103 is on the rotational path of the platen 101, indicated by reference symbol T2 in FIG. 8. This position is close to the rotation center O2 of the platen 101, on the outer periphery of the polishing head 102, and at a position that intersects with the retaining ring 104.

[0004] That is, polishing by CMP is performed by attaching the wafer W to a rotating polishing head 102 so that the wafer W can rotate integrally with the rotating polishing head 102, pressing one surface of the wafer W against a rotating platen 101 with a predetermined pressure, and supplying abrasive (slurry), which is a mixture of abrasives and chemicals, between the wafer W and the platen 101 from a slurry outlet 103a of a slurry nozzle 103.

[0005] In conventional CMP apparatuses, the rotation speed of the polishing mechanism, such as the platen 101 and polishing head 102, is not particularly high, at about 120 rpm, and the slurry on the platen 101 rarely scatters even when it collides with the polishing head 102 or the platen 101. For this reason, in conventional CMP apparatuses, the polishing head 102, the platen 101, etc. are not provided with measures to prevent slurry from scattering. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-73993 Summary of the Invention [Problem to be solved by the invention]

[0007] However, today, polishing mechanisms are being designed to rotate at higher speeds, with the rotation speeds of the platen and polishing head both reaching 200 to 300 rpm. As a result, when the slurry carried by the platen rotating at high speed hits the retaining ring, which is also rotating at high speed together with the polishing head, it is repelled by the retaining ring and scattered, resulting in the problem of the slurry adhering to the walls and ceiling of the processing chamber.

[0008] Furthermore, because slurry is expensive, used slurry is often collected in a tray installed on the floor of the processing chamber and reused. Therefore, if the slurry adheres to the walls or ceiling of the processing chamber, the amount of slurry that can be recovered when the slurry is reused decreases, which is a problem in that the efficiency of slurry utilization decreases.

[0009] In addition, slurry that has scattered on the ceiling and walls of the processing chamber is washed off with a shower of water (pure water) and collected in a tray also installed on the floor for reuse. However, because the slurry contains abrasives and chemicals, using water to wash off the slurry that has scattered on the ceiling and walls of the processing chamber dilutes the chemicals (resulting in a decrease in dilution rate), making reuse difficult.

[0010] Therefore, there is a technical problem that needs to be solved in order to suppress the scattering of slurry during processing, increase the amount of slurry recovered, improve utilization efficiency, and at the same time, make it easier to regenerate the slurry.The present invention aims to solve this problem. [Means for solving the problem]

[0011] The present invention has been proposed to achieve the above-mentioned object, and the invention described in claim 1 provides a CMP apparatus that presses one side of a wafer, which rotates integrally with a polishing head, against a rotating platen and polishes the one side of the wafer with slurry supplied between the wafer and the platen, and that is provided with a cover that covers the periphery of the polishing head from above to prevent slurry from scattering.

[0012] According to this configuration, the slurry that splashes due to collisions with the polishing head or retainer ring, which are rotating at high speed, is captured by the slurry splash prevention cover that covers the polishing head from above, thereby preventing the slurry from splashing outside the polishing head. This allows the slurry used for polishing wafers to be always returned to its designated location and easily reused. Furthermore, by eliminating the slurry that splashes and adheres to the ceiling and walls of the processing chamber and reducing the need to wash the slurry off with water on the ceiling and walls of the processing chamber, the dilution of the recovered slurry is prevented.

[0013] A second aspect of the present invention provides a CMP apparatus having the first aspect, wherein the slurry scattering prevention cover is detachable from the polishing head.

[0014] According to this configuration, the slurry scattering prevention cover, which can be retracted from the polishing head, can be temporarily retracted when replacing consumables on the retainer ring side, so as not to interfere with maintenance work.

[0015] A third aspect of the present invention provides a CMP apparatus according to the first or second aspect, wherein the slurry is supplied on a rotational path that passes through the center of rotation of the polishing head in a plan view.

[0016] With this configuration, the slurry supply position is moved from a conventional position close to the center of the platen in a planar view to a rotational orbit that passes near the rotation center of the polishing head, thereby suppressing the scattering of slurry caused by collision with the rapidly rotating polishing head or retaining ring.

[0017] A fourth aspect of the present invention provides a CMP apparatus having the configuration according to any one of the first to third aspects, further comprising a wall material for preventing slurry from scattering, which is provided to surround the periphery of the platen.

[0018] According to this configuration, the wall material for preventing slurry scattering captures the slurry scattered from the platen and always returns it to a predetermined position, allowing it to be easily reused.

[0019] The invention described in claim 5 provides a CMP apparatus that presses one side of a wafer, which rotates integrally with a polishing head, against a rotating platen and polishes the one side of the wafer with slurry supplied between the wafer and the platen, wherein the slurry is supplied on a rotational orbit that passes near the center of rotation of the polishing head in a planar view.

[0020] With this configuration, the slurry supply position is moved from a conventional position close to the center of the platen in a planar view to a rotational orbit that passes near the rotation center of the polishing head, thereby suppressing the scattering of slurry caused by collision with the rapidly rotating polishing head or retaining ring. [Effects of the Invention]

[0021] According to the invention, the slurry that is scattered when it collides with the polishing head or retainer ring rotating at high speed is captured by the slurry scattering prevention cover that covers the polishing head from above, and the slurry used for polishing wafers can always be returned to the designated location and easily reused. This improves the reuse rate of the slurry and contributes to cost reduction. Furthermore, this eliminates the need for slurry to scatter and adhere to the ceiling and walls of the processing chamber, and also eliminates the need to wash it off with water, making it easier to regenerate the slurry. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a diagram schematically illustrating a CMP apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view schematically showing the configuration of the main part of the CMP apparatus. [Figure 3] 1A and 1B are diagrams showing a schematic view of the main part of the polishing head in the CMP apparatus, in which (a) is a longitudinal cross-sectional view and (b) is an enlarged view of part B in (a). [Figure 4] FIG. 2 is a perspective view showing a part of a cover for preventing slurry from scattering provided on the polishing head, with a part cut away. [Figure 5] FIG. 2 is a perspective view schematically showing the configuration of a wall material for preventing slurry scattering in the CMP apparatus. [Figure 6] FIG. 10 is a diagram illustrating the position of the wall material for preventing slurry scattering. [Figure 7] FIG. 1 is a diagram showing slurry loss evaluation data for the CMP apparatus of the present invention and a conventional CMP apparatus. [Figure 8] FIG. 1 is a diagram schematically illustrating a main part of a conventional CMP apparatus. DETAILED DESCRIPTION OF THE INVENTION

[0023] In order to achieve the objectives of suppressing slurry scattering during processing, increasing the amount of slurry recovered to improve utilization efficiency, and at the same time facilitating the regeneration of slurry, the present invention provides a CMP apparatus in which one side of a wafer rotating integrally with a polishing head is pressed against a rotating platen, and the one side of the wafer is polished with slurry supplied between the wafer and the platen, and the apparatus is configured to include a cover for preventing slurry scattering that covers the polishing head from above. [Example]

[0024] An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. In the following embodiment, when the number, value, amount, range, etc. of components is mentioned, the number is not limited to the specific number, and may be more or less than the specific number, unless otherwise specified or when it is clearly limited to a specific number in principle.

[0025] Furthermore, when referring to the shape or positional relationship of components, etc., it includes things that are substantially similar or approximate to those shapes, etc., unless otherwise specified or when it is clearly considered otherwise in principle.

[0026] In addition, the drawings may exaggerate characteristic parts to make the features easier to understand, and the dimensional proportions of the components may not be the same as in reality. In addition, in cross-sectional views, hatching of some components may be omitted to make the cross-sectional structure of the components easier to understand.

[0027] In the following description, expressions indicating directions such as up, down, left, and right are not absolute, but are appropriate when each part of the CMP apparatus of the present invention is in the illustrated position, but if the position changes, they should be interpreted accordingly. Furthermore, the same elements are designated by the same reference numerals throughout the description of the embodiments.

[0028] Fig. 1 is a diagram schematically illustrating a CMP apparatus 10 according to one embodiment of the present invention. The CMP apparatus 10 shown in Fig. 1 polishes one surface of a wafer W (see Fig. 3) to a flat surface, and includes a platen 12, a polishing head 13, a slurry nozzle 14, a dressing unit 15, and the like arranged within a processing chamber 11. The processing chamber 11 is formed into a substantially sealed space by providing an opening 11B in a front wall surface 11a that is opened and closed by an opening / closing door 11A.

[0029] In the processing chamber 11, the wafer W to be polished is attached to the polishing head 13. The retainer 40 and the wafer W rotate integrally with the polishing head 13. As the polishing head 13 rotates, it presses one side of the wafer W against the platen 12, which is also rotating, with a predetermined pressure. The slurry nozzle 14 ejects slurry from the slurry ejection port 14a onto the platen 12, supplying a polishing material (not shown), which is a mixture of an abrasive and a chemical agent, i.e., CMP slurry (hereinafter simply referred to as "slurry"), between the wafer W held by the retainer ring 41A and the platen 12. In the CMP apparatus 10 of this embodiment, the position at which the slurry is ejected from the slurry ejection port 14a of the slurry nozzle 14 is on the rotational orbit indicated by the symbol T1 in FIG. 1. This position corresponds to the rotational center O1 of the polishing head 13 and the wafer W in a plan view.

[0030] The processing chamber 11 also includes a slurry tray 70 for receiving the slurry, and a wall member 80 for preventing the slurry from scattering, which is provided to surround the side surface of the platen 12.

[0031] The slurry receiving pan 70 is a receiving pan for receiving and recovering used slurry that has been discharged from the slurry nozzle 14. The slurry receiving pan 70 is provided with a slurry discharge port 70a at an appropriate position for discharging the slurry that has dropped onto the slurry receiving pan 70 toward a predetermined slurry recovery layer (not shown).

[0032] FIG. 2 is a perspective view showing a schematic configuration of the main part of the CMP apparatus 10 shown in FIG. 1, and shows the platen 12 and the polishing head 13. As shown in FIG.

[0033] The platen 12 is formed in a disk shape and is connected to a rotary shaft 16 disposed below the platen 12. When the rotary shaft 16 is rotated by the drive of a motor 17, the platen 12 rotates in the direction of arrow D1 in Fig. 2. A polishing pad 18 is attached to the upper surface of the platen 12, and a slurry is supplied onto the polishing pad 18 from a slurry nozzle 14.

[0034] The polishing head 13 is formed in a disk shape with a smaller diameter than the platen 12, and is connected to a rotary shaft 19 disposed above the polishing head 13. The rotary shaft 19 is rotated by a motor (not shown), causing the polishing head 13 to rotate in the direction of arrow D2 in FIG. 2. The polishing head 13 can be raised and lowered in the vertical direction V by an elevator (not shown). When polishing a wafer W, the polishing head 13 descends to press the wafer W against the polishing pad 18. The wafer W to be polished by the polishing head 13 is transferred by a wafer transfer mechanism (not shown).

[0035] The operation of the CMP apparatus 10 is controlled by a control means (not shown). The control means controls each of the components that make up the CMP apparatus 10. The control means is, for example, a computer, and is composed of a CPU, memory, etc. The functions of the control means may be realized by control using software, or may be realized by something that operates using hardware.

[0036] Next, we will explain the polishing head 13. Figure 3 shows a schematic diagram of the main part of the polishing head 13, where (a) is a vertical cross-sectional view and (b) is an enlarged view of part B in (a).

[0037] The polishing head 13 includes a head body 20 , a carrier 30 , a retainer 40 , a membrane film 50 , and a backing film 60 .

[0038] The head body 20 is connected to the rotary shaft 19 and rotates together with the rotary shaft 19. The head body 20 is connected to a carrier 30 disposed below the head body 20 via a rotating part 21, and the head body 20 and the carrier 30 rotate in unison.

[0039] The carrier 30 is provided with air lines 31 arranged at equal intervals around the periphery of the carrier 30. The lower ends of the air lines 31 open into an air chamber A formed between the underside 30a of the carrier 30 and the membrane film 50. The air lines 31 are connected to an air supply source serving as air supply means (not shown), and air is introduced into the air chamber A via the air lines 31. The pressure of the air supplied to the air lines 31 is adjusted by a regulator (not shown). The air supplied into the air chamber A forms an air layer above the membrane film 50 by a rim formed on the outer periphery of the carrier 30, and presses the entire surface of the membrane film 50 downward.

[0040] A carrier pressing means 32 is provided between the head main body 20 and the carrier 30. The carrier pressing means 32 is an air bag or the like that is inflated by air supplied from an air supply source (not shown). The pressure of the air supplied from the air supply source is adjusted by a regulator (not shown). The carrier pressing means 32 presses the wafer W against the polishing pad 18 via the carrier 30 in accordance with the pressure of the supplied air.

[0041] The retainer 40 is disposed so as to surround the periphery of the carrier 30. The retainer 40 includes a retainer ring 41A and a retainer ring holder 41B that can contact the polishing pad 18. The retainer ring 41A and the retainer ring holder 41B are attached to a retainer pressing member 43 via a snap ring 42. The retainer ring 41A is formed in an annular shape and includes a storage pocket 41a in the center that stores the wafer W, and a membrane film 50 is attached to the upper surface.

[0042] A retainer pressing means 44 is provided between the head body 20 and the retainer pressing member 43. Reference numeral 45 denotes a snap ring cover that covers the top of the snap ring 42, and reference numeral 46 denotes a cover attached to the snap ring cover 45 to prevent slurry from scattering.

[0043] The retainer pressing means 44 is an air bag or the like that is inflated by air supplied from an air supply source (not shown). The pressure of the air supplied from the air supply source is adjusted by a regulator (not shown). The retainer pressing means 44 presses the retainer 40 against the polishing pad 18 via the retainer pressing means 44 in accordance with the pressure of the supplied air.

[0044] The membrane film 50 is attached to the retainer ring 41A so as to cover the storage pocket 41a, and when compressed air is introduced into the air chamber A, the membrane film 50 is elastically deformed toward the inside of the storage pocket 41a by the air pressure.

[0045] The backing film 60 is, for example, a suede film. The backing film 60 is attached to the membrane film 50 with its center positioned on the rotation axis 19 of the polishing head 13. When compressed air is introduced into the air chamber A, the backing film 60 elastically deforms in accordance with the elastic deformation of the membrane film 50, thereby applying pressure to the wafer W.

[0046] The slurry-splash prevention cover 46 is attached to the outside of the snap ring cover 45, covering the lower peripheral surface of the polishing head 13 from above. That is, as shown in FIG. 3, the slurry-splash prevention cover 46 is attached to the polishing head 13, covering the side surfaces of the snap ring cover 45 and the side surfaces of the retainer ring 41A. As shown in FIG. 4, the slurry-splash prevention cover 46 is an annular member, and an inward flange portion 46a having an opening 47 in the center is provided on the upper end side. When the slurry-splash prevention cover 46 is placed over the snap ring cover 45, i.e., from above the polishing head 13, the central protrusion 45a of the snap ring cover 45 is received in the opening 47, and the inner surface of the inward flange portion 46a abuts against the shoulder portion 45b of the snap ring cover 45, thereby attaching the snap ring cover 45. After attachment, the cover 46 is fixed to the snap ring cover 45 (not shown) and rotates integrally with the polishing head 13. The bottom length of the cover 46 for preventing slurry scattering is set to a distance S3 of approximately 2.8 to 3.6 mm from the underside of the retainer ring 41A to the bottom of the cover 46 for preventing slurry scattering, as shown in Figure 3(b). The cover 46 for preventing slurry scattering is made of a material such as polyacetal, which has excellent abrasion resistance, impact resistance, and chemical resistance.

[0047] The slurry scattering prevention wall material 80 is shown in Figures 1 and 5. The slurry scattering prevention wall material 80 is made up of a first strip-shaped wall material 80a and a second strip-shaped wall material 80b, and a pair of fixing brackets 81 connecting the first strip-shaped wall material 80a and the second strip-shaped wall material 80b to each other.

[0048] The pair of fixing brackets 81 are made of metal members such as stainless steel, and as shown in Fig. 5, have a horizontal piece 81a and a vertical piece 81b that rises upward from one side of the horizontal piece 81a, and are formed into a generally L-shaped cross section. The pair of fixing brackets 81 are arranged with the vertical pieces 81b facing each other and adjacent to the opposing left and right side walls 11b, 11c of the processing chamber 11, with the platen 12 sandwiched between them, and the horizontal piece 81a is fixedly attached to the slurry receiving pan 70.

[0049] The first strip-shaped wall material 80a and the second strip-shaped wall material 80b in the wall material 80 for preventing slurry scattering are made of polyester film, for example, about 0.35 mm thick, which has excellent chemical resistance, is easy to process so that it can be installed in the complex processing chamber 11, and is also easy to attach and detach, and each is bent into an approximately U-shape when viewed from above.

[0050] The first band-shaped wall material 80a surrounds the outer peripheral surface of the front half of the platen 12 with both ends 80aa of the first band standing vertically, and is brought into face-to-face contact with the vertical pieces 81b of a pair of fixed brackets 81, with each end 80aa being fixed to the vertical pieces 81b with a fixed pin 83. The first band-shaped wall material 80a and the fixed bracket 81 are fixed in place in such a way that the first band-shaped wall material 80a can rotate up and down relative to the fixed bracket 81 around the fixed pin 83 as an axis, and can also be easily attached and detached.

[0051] On the other hand, the second strip-shaped wall material 80b, like the first strip-shaped wall material 80a, has both sides of the strip standing vertically, surrounding the outer periphery of the rear half of the platen 12, and both end portions 80ba are respectively abutted against the vertical piece portions 81b of a pair of fixing brackets 81, with each end portion 80aa and the vertical piece portions 81b fixed with a fixing pin 83.

[0052] As a result, the first strip-shaped wall material 80a and the second strip-shaped wall material 80b are connected at a pair of both end portions 80aa and 80ba via a pair of fixing brackets 81, and the entire outside of the outer circumferential surface of the platen 12 is surrounded by the first strip-shaped wall material 80a and the second strip-shaped wall material 80b. The reason why the first strip-shaped wall material 80a arranged on the opening 11B side of the processing chamber 11 can rotate up and down about the fixing pin 83 as an axis and is also easily attached and detached is to prevent the slurry-splash prevention wall material 80 from getting in the way when replacing consumables such as the polishing head 13 and the polishing pad 18.

[0053] As shown in FIG. 6, the installation specifications of the slurry-scattering prevention wall material 80 in this embodiment are as follows: the minimum distance S1 between the inner surface of the slurry-scattering prevention wall material 80 and the peripheral surface of the platen 12 is set to approximately 4 mm, and the height S2 from the upper surface of the platen 12 (polishing pad 18) to the upper edge 80c of the slurry-scattering prevention wall material 80 is set to 28 mm.

[0054] In the CMP apparatus 10 configured as described above, the wafer W to be polished is attached to the polishing head 13 in the processing chamber 11. The retainer ring 41A and the wafer W rotate integrally with the polishing head 13, and while rotating, the polishing head 13 presses one surface of the wafer W against the platen 12, which is also rotating, with a predetermined pressure. Slurry is supplied from the slurry discharge port 14a of the slurry nozzle 14 onto the platen 12, and the supplied slurry enters between the polishing pad 18 on the platen 12 and the polishing head 13, i.e., between the polishing pad 18 and one surface of the wafer W, thereby polishing one surface of the wafer W to a flat surface.

[0055] When the slurry supplied onto the rotating platen 12 is sent to the polishing head 13, which is also rotating, it passes through the gap between the slurry splash prevention cover 46 and the platen 12, enters the underside of the retaining ring 41A, and further enters the underside (one side) of the wafer W placed in the storage pocket 41a, thereby contributing to the CMP polishing of the wafer W. However, during processing, some of the slurry, indicated by reference numeral 84 in FIG. 3(b), collides with the peripheral surface of the retaining ring 41A, which rotates integrally with the polishing head 13, and splashes. However, in the CMP apparatus 10 of this embodiment, the slurry splash prevention cover 46 is attached to the outside of the snap ring cover 45, covering the lower peripheral surface of the polishing head 13. Therefore, the slurry that hits the peripheral surface of the retainer ring 41A and bounces off hits the inner surface of the slurry splash prevention cover 46 and falls onto the platen 12, then flows toward the outer periphery on the platen 12 and falls from the outer periphery of the platen 12 onto the slurry receiving pan 70. This suppresses the slurry that hits the peripheral surface of the retainer ring 41A and bounces off, and reliably prevents the slurry from splashing onto the ceiling or side surfaces inside the processing chamber 11 and adhering to them.

[0056] Furthermore, the slurry supplied onto the platen 12 and used for CMP polishing is forced to flow toward the outer periphery by the centrifugal force of the rotating platen 12 and falls from the outer periphery of the platen 12 onto the slurry receiving tray 70. The slurry that falls onto the slurry receiving tray 70 is discharged out of the processing chamber 11 through the slurry outlet 70a and collected in a predetermined location for reuse. However, some of the slurry is scattered far outward due to the centrifugal force of the platen 12. However, in the CMP apparatus 10 of this embodiment, a slurry scattering prevention wall material 80 is provided surrounding the side of the platen 12. The slurry scattered outward by the centrifugal force of the platen 12 hits the inner surface of the slurry scattering prevention wall material 80, falls onto the slurry receiving tray 70, is discharged out of the processing chamber 11 through the slurry outlet 70a, and collected in a predetermined location for reuse. This prevents the slurry thrown outward by the centrifugal force of the platen 12 from scattering and adhering to the wall surfaces and the like within the processing chamber 11.

[0057] Therefore, in the CMP apparatus 10 of this embodiment, by suppressing the scattering and adhesion of slurry to the ceiling and walls of the processing chamber 11, the work of washing off the slurry by pouring water on the ceiling and walls can be reduced. This simplifies the work and contributes to improving workability. At the same time, eliminating the work of washing off the slurry by pouring water can prevent the slurry from becoming diluted, making it easier to regenerate the slurry.

[0058] Furthermore, in the CMP apparatus 10 of this embodiment, the slurry scattering prevention cover 46 is provided so that it can be temporarily retracted from the polishing head 13, and therefore can be removed when replacing consumables on the retainer 40 side, etc., so as not to interfere with maintenance work.

[0059] In addition, in the CMP apparatus 10 of this embodiment, the first strip-shaped wall material 80a of the wall material 80 for preventing slurry scattering, which is installed on the opening 11B side of the processing chamber 11, is arranged to be rotatable and detachable in the vertical direction relative to the platen 12, with the fixing pin 83 as the axis, so that it does not interfere with maintenance work on the platen 12 or the polishing head 13.

[0060] Furthermore, in the CMP apparatus 10 of this embodiment, the position at which the slurry is supplied onto the platen 12 is set on the rotational orbit T1 of the platen 12, which passes near the rotation center O1 of the polishing head 13 (wafer W) when viewed in a plane, thereby reducing the amount of slurry that splashes due to contact with the retainer ring 41A, etc., which rotates at high speed together with the polishing head 13.

[0061] The supply position of the slurry onto the platen 12 may be any position as long as the rotational path of the slurry on the platen 12 does not oppose the outer circumferential path of the polishing head 13 (wafer W). In other words, the rotational path T1 of the platen 12, which indicates the supply position of the slurry, may be any position as long as it passes near the rotation center O1 of the polishing head 13 (wafer W).

[0062] Next, we will explain the evaluation data of the slurry loss rate shown in Figure 7. Figure 7 shows the loss (cc) of slurry recovered during 10 minutes when 200 ml / min of slurry was supplied. In Figure 7, (a) to (g) show the loss of slurry recovered during 10 minutes when the following configurations were implemented. (a) shows the amount of slurry loss when the platen 12 and polishing head 13 are rotated at 200 rpm without either the slurry scattering prevention cover 46 or the slurry scattering prevention wall material 80, and the loss amount is approximately 620 cc. (b) shows the amount of slurry loss when the platen 12 and polishing head 13 are rotated at 200 rpm without the slurry scattering prevention cover 46 and only the slurry scattering prevention wall material 80, and the amount of loss is approximately 490 cc. (c) shows, like (b), the amount of loss when the slurry scattering prevention cover 46 is not provided and only the slurry scattering prevention wall material 80 is provided, and the platen 12 and polishing head 13 are rotated at 300 rpm, and the amount of loss is approximately 529 cc. (d) shows the amount of slurry loss when the platen 12 and polishing head 13 are rotated at 200 rpm without the slurry scattering prevention wall material 80 and only the slurry scattering prevention cover 46 is installed, and the amount of loss is approximately 191 cc. (e) shows the amount of slurry loss when the platen 12 and polishing head 13 were rotated at 300 rpm without the slurry scattering prevention wall material 80 and only the slurry scattering prevention cover 46 was installed, and the amount of loss was approximately 297 cc. (f) shows the amount of slurry loss when the platen 12 and polishing head 13 are rotated at 300 rpm without the slurry scattering prevention cover 46 or the slurry scattering prevention wall material 80, and the slurry is supplied onto the platen 12 at the rotation center O1 of the polishing head 13, i.e., on the central path of the wafer W to be polished, and the amount of loss is approximately 207 cc. (g) shows the amount of slurry loss when the platen 12 and polishing head 13 are rotated at 300 rpm, with a cover 46 for preventing slurry scattering and a wall material 80 for preventing slurry scattering installed, and the position at which the slurry is supplied onto the platen 12 is the center of rotation O1 of the polishing head 13, i.e., on the central path of the wafer W to be polished. The amount of loss is approximately 185 cc. Therefore, it can be seen that the amount of slurry loss can be further reduced by providing a cover 46 for preventing slurry scattering and a wall material 80 for preventing slurry scattering, and by adjusting the position at which the slurry is supplied onto the platen 12 so that it is supplied at the center O1 of rotation of the polishing head 13, i.e., on the central path of the wafer W to be polished.

[0063] The present invention can be modified in various ways without departing from the spirit of the present invention, and it goes without saying that the present invention also covers such modifications. [Explanation of symbols]

[0064] 10:CMP equipment 11: Processing room 11A: Opening and closing door 11B: Opening 11a: Front wall 11b: Side wall 11c: Side wall 12: Platen 13: Polishing head 14: Slurry nozzle 14a: Slurry discharge port 16: Rotation axis 17: Motor 18: Polishing pad 19: Rotation axis 20: Head body 21: Rotating part 30: Career 30a: Bottom surface 31:Airline 32: Carrier pressing means 40: Retainer 41A: Retainer ring 41B: Retainer ring holder 41a: Storage pocket 42: Snap ring 43: Retainer pressing member 44: Retainer pressing means 45: Snap ring cover 45a: Central convex part 45b: Shoulder 46: Slurry splash prevention cover 46a: Inward flange 47 :Aperture 50:Membrane film 60: Backing film 70: Slurry tray 70a: Slurry outlet 80: Wall material for preventing slurry scattering 80a: First strip wall material 80aa: end 80b: Second wall strip 80ba: Both ends 81: Fixed bracket 81a: Horizontal piece 81b: Vertical piece 83: Fixed pin A: Air chamber O1: Center of rotation S1 :Distance S2: Height S3: Distance T1: Rotation orbit V: Vertical direction W: Wafer

Claims

1. 1. A CMP apparatus in which one surface of a wafer attached to a retainer ring and rotating integrally with a polishing head is pressed against a rotating platen, and one surface of the wafer is polished with a slurry supplied between the wafer and the platen, a slurry scattering prevention cover that covers the polishing head from above; A CMP apparatus characterized by:

2. 2. The CMP apparatus according to claim 1, wherein the slurry scattering prevention cover is retractable relative to the polishing head.

3. 3. The CMP apparatus according to claim 1, wherein the slurry is supplied on a rotational path passing near the center of rotation of the polishing head in a plan view.

4. 4. The CMP apparatus according to claim 1, further comprising a wall member surrounding the periphery of the platen for preventing slurry from scattering.

5. 1. A CMP apparatus in which one surface of a wafer rotating integrally with a polishing head is pressed against a rotating platen, and the one surface of the wafer is polished with a slurry supplied between the wafer and the platen, CMP apparatus, characterized in that the slurry is supplied on a rotational orbit that passes near the center of rotation of the polishing head in a plan view.

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