Grinding equipment and grinding methods

Abstract

The grinding apparatus includes multiple retaining discs, a tool drive unit, a stage, and a stage cover. The retaining discs hold a substrate. The tool drive unit drives a grinding tool pressed against the substrate. The stage holds the multiple retaining discs about a rotation center line and rotates around the rotation center line. The stage cover rotates together with the stage. The stage cover includes an inclined portion that slopes downwards towards the rotation center line. The grinding apparatus includes a nozzle. The nozzle supplies cleaning fluid to the inclined portion between the top of the inclined portion and the retaining discs.

Description

Technical Field

[0001] This disclosure relates to grinding apparatus and grinding methods. Background Technology

[0002] The processing apparatus described in Patent Document 1 includes a turntable, a pair of holding tables, processing components, and a water tank. The water tank has an opening that exposes the turntable, receives processing waste liquid flowing down from the turntable, including processing chips generated during the processing of the workpiece, and drains water from a drain outlet.

[0003] The grinding apparatus described in Patent Document 2 comprises: a holding table; a grinding component that supplies grinding water and performs grinding; a rotary table having two or more holding tables arranged at equal angles around a rotation axis; and a table cover that covers the upper surface of the rotary table. The upper surface of the table cover is inclined downwards in the outward peripheral direction from the rotation axis. Grinding water is discharged from the outlet of a water tank. A screen for collecting grinding chips mixed in the grinding water is placed at the outlet of the water tank. The grinding chips are appropriately removed from the screen.

[0004] The planar machining apparatus described in Patent Document 3 includes a partition plate. The partition plate is fixed to an indexing table and is formed in a cross shape to separate four retaining discs disposed on the indexing table. The planar machining apparatus has a housing that houses the retaining discs and the indexing table, inside which grinding fluid is supplied to the substrate while grinding the substrate using a grinding stone. Brushes are mounted on the upper surface and sides of the housing. When the retaining discs are in the machining position, the brushes contact the upper surface and sides of the partition plate.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2017-222015

[0008] Patent Document 2: Japanese Patent Application Publication No. 2013-188813

[0009] Patent Document 3: Japanese Patent Application Publication No. 2010-124006 Summary of the Invention

[0010] The problem the invention aims to solve

[0011] One technical solution disclosed herein provides a technique for suppressing the deposition of grinding chips around the retaining disk.

[0012] Solution for solving the problem

[0013] A grinding apparatus according to this disclosure includes multiple retaining discs, a tool drive unit, a stage, and a stage cover. The retaining discs hold a substrate. The tool drive unit drives a grinding tool pressed against the substrate. The stage holds the multiple retaining discs about a rotation center line and rotates around the rotation center line. The stage cover rotates together with the stage. The stage cover includes an inclined portion that slopes downwards the further away from the rotation center line. The grinding apparatus includes a nozzle. The nozzle supplies cleaning fluid to the inclined portion between the top of the inclined portion and the retaining discs.

[0014] The effects of the invention

[0015] According to a technical solution disclosed herein, it is possible to suppress the deposition of grinding chips around the retaining disk. Attached Figure Description

[0016] Figure 1 This is a top view of a grinding apparatus according to one embodiment, shown through the upper panel of the housing.

[0017] Figure 2 This is a cross-sectional view showing an example of a tool drive unit.

[0018] Figure 3 This is a perspective view showing an example of a housing being fed into or out of its chamber.

[0019] Figure 4 Figure (A) is an example of a fixed partition wall. Figure 4 (B) is from Figure 4 The image observed in the direction of arrow B in (A), Figure 4 (C) is from Figure 4 The diagram (A) is viewed through the side wall in the direction of arrow C. Figure 4 (D) is along Figure 4 A cross-sectional view of line D-D of (C).

[0020] Figure 5 This is a cross-sectional view showing an example of a retaining disc cover, platform cover, and base cover.

[0021] Figure 6 (A) represents Figure 5 A top view of an example of the inner cylinder section shown. Figure 6 (B) indicates that Figure 6 A top view of an example of a state in which part of the inner cylinder of (A) has been removed.

[0022] Figure 7 It means to Figure 5 The cross-sectional view shows an example of a partially removed inner cylinder section.

[0023] Figure 8This is a top view illustrating an example of the flow of cleaning fluid.

[0024] Figure 9 (A) is a cross-sectional view showing an example of an exhaust box, and is along... Figure 9 A sectional view of line A-A in (B). Figure 9 (B) indicates from Figure 9 A diagram of an example of a side panel and fixed partition wall observed in the direction of arrow B in (A).

[0025] Figure 10 (A) is a cross-sectional view showing an example of a disk as viewed from the X-axis direction. Figure 10 (B) is a cross-sectional view showing an example of the disk as viewed from the negative Y-axis direction. Figure 10 (C) is a cross-sectional view of an example of a disk as viewed from the positive Y-axis direction.

[0026] Figure 11 It means Figure 8 A top view of an example of the housing and tool drive unit shown.

[0027] Figure 12 This is a top view showing an example of the configuration of a liquid level sensor.

[0028] Figure 13 It is along Figure 12 A cross-sectional view of line XIII-XIII.

[0029] Figure 14 (A) is a perspective view showing an example of the external assembly of a grinding device. Figure 14 (B) is a perspective view showing an example of a recycling section.

[0030] Figure 15 (A) is a cross-sectional view showing an example of a destination for grinding chips. Figure 15 (B) is a cross-sectional view representing an example of a switched storage destination. Detailed Implementation

[0031] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Furthermore, sometimes the same or corresponding structures are labeled with the same reference numerals in the various drawings, and descriptions are omitted. In this specification, the X-axis, Y-axis, and Z-axis are mutually perpendicular directions. The X-axis and Y-axis are horizontal directions, and the Z-axis is a vertical direction.

[0032] First, refer to Figure 1The grinding apparatus 1 is described below. The grinding apparatus 1 grinds a substrate W. The substrate W includes a semiconductor substrate such as a silicon wafer or a compound semiconductor wafer, or a glass substrate. The substrate W may also include a device layer formed on the surface of the semiconductor substrate or the glass substrate. The device layer includes electronic circuitry. Alternatively, the substrate W may be an overlay substrate formed by bonding multiple substrates together. Grinding includes polishing. The grinding apparatus 1, for example, includes a stage 10, four holding disks 20, three tool drive units 30, a housing 40, and a control unit 16.

[0033] The control unit 16 is, for example, a computer, including a CPU (Central Processing Unit) 17 and a storage medium 18 such as a memory. The storage medium 18 stores programs that control various processes executed in the grinding apparatus 1. The control unit 16 controls the operation of the grinding apparatus 1 by causing the CPU 17 to execute the programs stored in the storage medium 18.

[0034] Stage 10 holds four retaining disks 20 around the rotation center line R1 and rotates around R1. When viewed from above, the rotation direction of stage 10 switches between clockwise and counterclockwise.

[0035] Four holding discs 20 are arranged at equal intervals around the rotation center line R1 of the stage 10. Each holding disc 20 rotates together with the stage 10 and moves sequentially to the feed-in / feed-out position A0, the first grinding position A1, the second grinding position A2, the third grinding position A3, and the feed-in / feed-out position A0.

[0036] The feed-in / feed-out position A0 is the position for feeding the substrate W relative to the holding disk 20, and serves as both the feeding and feeding position for the substrate W. The first grinding position A1 is the position for the first grinding of the substrate W. The second grinding position A2 is the position for the second grinding of the substrate W. The third grinding position A3 is the position for the third grinding of the substrate W. Furthermore, in this embodiment, the feed-in and feed-out positions are the same, but they can also be different.

[0037] The four retaining discs 20 are positioned around their respective rotation center lines R2 (see reference). Figure 2 It is mounted on the platform 10 with the center 20 rotating freely. Each holding plate 20 is provided with a holding plate drive unit 19 for driving the holding plate 20.

[0038] The retaining disc drive unit 19 includes, for example, a motor 19a that rotates the retaining disc 20. The rotational driving force of the motor 19a is transmitted to the retaining disc 20 via a timing belt or the like. Alternatively, gears may be used instead of a timing belt.

[0039] One tool drive unit 30 drives the grinding tool D for primary grinding. The tool drive unit 30 causes the grinding tool D to rotate and move up and down. Another tool drive unit 30 drives the grinding tool D for secondary grinding. The remaining tool drive unit 30 drives the grinding tool D for tertiary grinding.

[0040] Next, refer to Figure 2 The tool drive unit 30 is described below. The tool drive unit 30 includes a movable part 31 for mounting the grinding tool D. The grinding tool D presses against the substrate W and grinds the substrate W. The grinding tool D includes, for example, a disc-shaped grinding wheel D1 and a plurality of grinding stones D2 arranged in a ring on the lower surface of the grinding wheel D1.

[0041] The movable part 31 has a flange 32 for mounting a grinding tool D, a spindle 33 with the flange 32 at its lower end, and a spindle motor 34 for rotating the spindle 33. The flange 32 is horizontally arranged, and the grinding tool D is mounted on its lower surface. The spindle 33 is vertically arranged. The spindle motor 34 rotates the spindle 33, which in turn rotates the grinding tool D mounted on the flange 32. The rotation center line R3 of the grinding tool D is the rotation center line of the spindle 33.

[0042] The tool drive unit 30 also includes a lifting unit 35 that raises and lowers the movable part 31. The lifting unit 35 includes, for example, a vertical Z-axis guide 36, a Z-axis slider 37 that moves along the Z-axis guide 36, and a Z-axis motor 38 that moves the Z-axis slider 37. The movable part 31 is fixed to the Z-axis slider 37, and the movable part 31 and the grinding tool D rise and fall together with the Z-axis slider 37. The lifting unit 35 also includes a position detector 39 that detects the position of the grinding tool D. The position detector 39 detects, for example, the rotation of the Z-axis motor 38, and thus the position of the grinding tool D.

[0043] The lifting unit 35 lowers the grinding tool D from the standby position. The grinding tool D rotates as it descends, contacting the upper surface of the rotating substrate W and grinding the entire upper surface of the substrate W. When the thickness of the substrate W reaches a set value, the lifting unit 35 stops the descent of the grinding tool D. Then, the lifting unit 35 raises the grinding tool D back to the standby position.

[0044] The grinding apparatus 1 includes a housing 40 that houses multiple retaining discs 20. The housing 40 prevents grinding chips and grinding fluid from being dispersed to the outside. Grinding chips are powder or fragments generated during the grinding of the substrate W. The powder includes powder emanating from the substrate W and abrasive grains detached from the grinding tool D. The fragments are, for example, arc-shaped flakes generated at the periphery of the substrate W. The housing 40 may also house a stage 10.

[0045] The housing 40 has an upper panel 41 located above the retaining plate 20 and a side panel 42 located to the side of the retaining plate 20. The upper panel 41 is horizontal, and the side panel 42 is vertical. The upper panel 41 is located above the side panel 42. An insertion port 41a for the movable part 31 is formed on the upper panel 41.

[0046] like Figure 1 As shown by the dashed lines, the upper panel 41 covers, for example, the area above the first grinding position A1, the second grinding position A2, and the third grinding position A3. Furthermore, the upper panel 41 opens the area above the feed / outfeed position A0. For example, when viewed from above, the upper panel 41 has a shape formed by removing one corner of a rectangle in an L-shape.

[0047] like Figure 2 As shown, the grinding apparatus 1 includes a nozzle 50 for supplying grinding fluid to the substrate W held by the holding plate 20. The grinding fluid is, for example, pure water such as DIW (Deionized Water). The grinding fluid enters between the substrate W and the grinding tool D, reducing grinding resistance and suppressing heat generation. The nozzle 50 can also supply pure water, which serves as a cleaning fluid for the holding plate 20, to the holding plate 20 after the substrate W has been fed out.

[0048] like Figure 1 As shown, the grinding apparatus 1 includes a fixed partition wall 45 that divides the interior of the housing 40 into multiple chambers around the rotation center line R1 of the stage 10. The fixed partition wall 45 is fixed to the lower surface of the upper panel 41. When viewed from above, the fixed partition wall 45 extends radially (in a direction orthogonal to the rotation center line R1) of the stage 10.

[0049] The fixed partition wall 45 is, for example, cross-shaped, dividing the interior of the housing 40 into four chambers B0 to B3 around the rotation center line R1 of the stage 10. Three chambers B1 to B3 are grinding chambers for grinding the substrate W. B1 is the primary grinding chamber, B2 is the secondary grinding chamber, and B3 is the tertiary grinding chamber. The remaining chamber B0 is the feed-in / feed-out chamber for feeding the substrate W. Feeding the substrate W includes the following actions: the external conveying device and the holding plate 20 exchange substrate W.

[0050] When viewed from above, the interior of the housing 40 is sequentially divided into an infeed / outfeed chamber B0, a primary grinding chamber B1, a secondary grinding chamber B2, and a tertiary grinding chamber B3 in a counter-clockwise direction. Alternatively, the order of the four chambers B0 to B3 can be reversed, and when viewed from above, the interior of the housing 40 can also be sequentially divided into an infeed / outfeed chamber B0, a primary grinding chamber B1, a secondary grinding chamber B2, and a tertiary grinding chamber B3 in a clockwise direction.

[0051] like Figure 3As shown, the grinding apparatus 1 includes a plurality of rotating partition walls 15 that rotate together with the stage 10. The plurality of rotating partition walls 15 are respectively located between a plurality of circumferentially adjacent retaining discs 20 on the stage 10, rotate together with the stage 10, stop directly below a fixed partition wall 45, and contact the lower end of the fixed partition wall 45. The fixed partition wall 45 and the rotating partition walls 15 inhibit the movement of grinding chips and grinding fluid between adjacent chambers. Furthermore, the upper end of the rotating partition wall 15 and the lower end of the fixed partition wall 45 may not be in contact.

[0052] For example, the fixed partition wall 45 and the rotating partition wall 15 prevent grinding chips from entering the feed and discharge chamber B0 from the primary grinding chamber B1 and the tertiary grinding chamber B3, thus keeping the feed and discharge chamber B0 clean. Furthermore, the fixed partition wall 45 and the rotating partition wall 15 prevent larger primary grinding chips from entering the secondary grinding chamber B2 from the primary grinding chamber B1, thereby reducing the roughness of the ground surface after secondary grinding. Moreover, the fixed partition wall 45 and the rotating partition wall 15 prevent larger secondary grinding chips from entering the tertiary grinding chamber B3 from the secondary grinding chamber B2, thereby reducing the roughness of the ground surface after tertiary grinding.

[0053] like Figure 4 As shown, the fixed partition wall 45 includes radial ( ) of the platform 10. Figure 4 The upper wall 100 extends along the Y-axis, a first upper piece 111 is suspended from the upper wall 100 along the upper wall 100, and a second upper piece 112 is spaced apart from the first upper piece 111. The first upper piece 111 and the second upper piece 112 are, for example, resin sheets or rubber sheets.

[0054] Unlike the brush described in Patent Document 3, the first upper plate 111 and the second upper plate 112 impede the movement of grinding chips and grinding fluid not in a linear manner but in a surface manner. Furthermore, the first upper plate 111 and the second upper plate 112 impede the movement of grinding chips and grinding fluid in a dual manner. Therefore, they are more effective than ever in impeding the movement of grinding chips and grinding fluid between adjacent chambers.

[0055] like Figure 4 As shown in (B), the upper wall 100 has a horizontal portion 101 extending radially in the platform 10 and a vertical portion 102 protruding downward from one end of the horizontal portion 101 in the width direction at its lower end. The horizontal portion 101 and the vertical portion 102 form an L-shaped angle 103. The fixed partition wall 45 has a fixing device for fixing the first upper piece 111 and the second upper piece 112 to the vertical portion 102. This fixing device is not particularly limited, and may be, for example, a bolt 120.

[0056] Multiple bolts 120 are provided radially at intervals on the platform 10. The shank 121 of the bolt 120 passes through the through holes of the first upper plate 111 and the second upper plate 112, and is screwed into the bolt hole of the vertical portion 102. The head 122 of the bolt 120 presses against the first upper plate 111 and the second upper plate 112 through the pressure plate 123, etc.

[0057] By loosening and tightening bolt 120, the first upper piece 111 or the second upper piece 112 can be replaced. The size or shape of the first upper piece 111 can also be changed before or after replacement. The same applies to the second upper piece 112.

[0058] When viewed from above, the first upper piece 111, the second upper piece 112, and the head 122 of the bolt 120 do not protrude from the horizontal portion 101. This helps to suppress interference between the head 122 of the bolt 120 and other components.

[0059] The first upper piece 111 and the second upper piece 112 are arranged with spacers 114 and 115 between them, and protrude downward beyond the spacers 114 and 115. Through holes are formed in the spacers 114 and 115 for the shank 121 of the bolt 120 to pass through.

[0060] The fixed partition wall 45 may also include a third upper sheet 113 disposed between the first upper sheet 111 and the second upper sheet 112. The third upper sheet 113 is, for example, a resin sheet or a rubber sheet. The first upper sheet 111, the second upper sheet 112 and the third upper sheet 113 impede the movement of grinding chips and grinding fluid in a triple manner.

[0061] The third upper piece 113 and the first upper piece 111 are arranged with a spacer 114 between them, and protrude downward beyond the spacer 114. In addition, the third upper piece 113 and the second upper piece 112 are arranged with a spacer 115 between them, and protrude downward beyond the spacer 115.

[0062] like Figure 4 As shown by the double-dotted line in (B), when viewed radially from the stage 10, the upper end of the rotating partition wall 15 may also have an upwardly convex curved surface. The third upper piece 113 contacts the upper end of the rotating partition wall 15. On the other hand, the first upper piece 111 and the second upper piece 112 do not contact the upper end of the rotating partition wall 15.

[0063] The third upper piece 113 contacts the upper end of the rotating partition wall 15. Therefore, the thickness T3 of the third upper piece 113 can also be thicker than the thickness T1 of the first upper piece 111 and the thickness T2 of the second upper piece 112. This balances the durability of the third upper piece 113 with the flexibility of the first upper piece 111 and the second upper piece 112. The first upper piece 111 and the second upper piece 112 can also contact the upper end of the rotating partition wall 15 and deform in a manner mimicking its upper end.

[0064] Furthermore, a component other than the third upper plate 113, such as a brush, may be disposed between the first upper plate 111 and the second upper plate 112. Alternatively, neither the third upper plate 113 nor a brush, or any component, may be disposed between the first upper plate 111 and the second upper plate 112. Various sealing components can be replaced using the bolts 120, and the number of sealing components can be changed. Without the third upper plate 113, either or both of the first upper plate 111 and the second upper plate 112 are in contact with the upper end of the rotating partition wall 15. Furthermore, without the third upper plate 113, neither the first upper plate 111 nor the second upper plate 112 may be in contact with the upper end of the rotating partition wall 15.

[0065] The fixed partition wall 45 includes a side wall 130 located between the upper wall 100 and the side panel 42 and projecting downward beyond the upper wall 100, a first horizontal piece 141 projecting from the side wall 130 toward the platform 10, and a second horizontal piece 142 spaced apart from the first horizontal piece 141. The first horizontal piece 141 and the second horizontal piece 142 are, for example, resin sheets or rubber sheets.

[0066] like Figure 4 As shown in (C), the first horizontal piece 141 is, for example, disposed on the same plane as the first upper piece 111. The thickness of the first horizontal piece 141 may also be the same as the thickness T1 of the first upper piece 111. Furthermore, the second horizontal piece 142 is, for example, disposed on the same plane as the second upper piece 112. The thickness of the second horizontal piece 142 may also be the same as the thickness T2 of the second upper piece 112.

[0067] Unlike the brush described in Patent Document 3, the first horizontal blade 141 and the second horizontal blade 142 impede the movement of grinding chips and grinding fluid not in a linear manner but in a surface manner. Furthermore, the first horizontal blade 141 and the second horizontal blade 142 impede the movement of grinding chips and grinding fluid in a dual manner. Therefore, they are more effective than before in impeding the movement of grinding chips and grinding fluid between adjacent chambers.

[0068] The fixed partition wall 45 may also include a third cross section 143 disposed between the first cross section 141 and the second cross section 142. The third cross section 143 is, for example, a resin sheet or a rubber sheet.

[0069] The third horizontal piece 143 is, for example, disposed on the same plane as the third upper piece 113. The thickness of the third horizontal piece 143 may also be the same as the thickness T3 of the third upper piece 113. The thickness of the third horizontal piece 143 is greater than the thickness of the first horizontal piece 141 and the thickness of the second horizontal piece 142.

[0070] like Figure 4As shown in (C), the third transverse blade 143 protrudes upwards from the first transverse blade 141 and the second transverse blade 142, entering between the first upper blade 111 and the second upper blade 112. As a result, even if a gap exists between the first upper blade 111 and the first transverse blade 141, the third transverse blade 143 can seal the gap, preventing the movement of grinding chips and grinding fluid through the gap. Similarly, even if a gap exists between the second upper blade 112 and the second transverse blade 142, the third transverse blade 143 can seal the gap, preventing the movement of grinding chips and grinding fluid through the gap.

[0071] like Figure 4 As shown in (D), the first upper plate 111 and the second upper plate 112 protrude toward the sidewall 130 more than the third upper plate 113. As a result, even if there is a gap between the third upper plate 113 and the third transverse plate 143, the gap can be hidden by the first upper plate 111 and the second upper plate 112, which can prevent grinding chips and grinding fluid from moving through the gap.

[0072] Next, refer to Figure 5 This indicates that the disk cover should be kept at 70 degrees. For example... Figure 5 As shown, the grinding apparatus 1 includes a retaining disk cover 70, which rotates together with the retaining disk 20. The retaining disk 20 includes a retaining platform 21 for holding the substrate W and a flange 23 provided at the lower edge of the retaining platform 21. The retaining platform 21 has a porous material 21a and a base 21b. A recess is formed on the upper surface of the base 21b, and a disc-shaped porous material 21a is embedded in the recess.

[0073] When the gas inside the porous body 21a is drawn out, and the gas pressure in the porous body 21a becomes a negative pressure lower than atmospheric pressure, the substrate W is adsorbed onto the porous body 21a. On the other hand, when the gas drawing stops and the gas pressure in the porous body 21a returns to atmospheric pressure, the adsorption of the substrate W is released.

[0074] The retaining plate 20 is placed on the rotary table 25 and secured to the rotary table 25 using a fixing device. This fixing device is not particularly limited, but may be, for example, bolts 24. Multiple bolts 24 are spaced apart circumferentially on the flange 23 of the retaining plate 20. The shank of the bolt 24 passes through a through hole in the flange 23 and is screwed into a bolt hole in the rotary table 25. The head of the bolt 24 presses against the flange 23 from above. By loosening and tightening the bolts 24, the retaining plate 20 can be replaced.

[0075] The retaining disc cover 70 includes an annular awning 71. An opening 71a is formed in the center of the annular awning 71 for the retaining platform 21 of the retaining disc 20 to enter. The upper surface of the awning 71 is positioned at the same height as or below the upper surface of the retaining platform 21 of the retaining disc 20. Furthermore, the upper surface of the awning 71 is positioned above the inclined portion 61 of the platform cover 60, which will be described later.

[0076] The upper surface of the visor 71 slopes downwards the further it is from the rotation center line R2 of the retaining disc 20. Alternatively, the upper surface of the visor 71 can be horizontal. However, if the upper surface of the visor 71 is sloped, the grinding fluid can be discharged downwards under gravity, thus suppressing the deposition of grinding chips mixed in the grinding fluid. The upper surface of the visor 71 may, for example, have a conical shape.

[0077] The visor 71 is positioned above the flange 23 of the retaining plate 20, covering the bolt 24, which serves as a fixing device, from above. The diameter of the opening 71a formed in the center of the visor 71 is larger than the diameter of the retaining plate 21 but smaller than the diameter of the flange 23. This allows the bolt 24 to be hidden directly below the visor 71, suppressing collision between the grinding fluid and the bolt 24 and preventing the grinding fluid from scattering.

[0078] According to this embodiment, the retaining disk cover 70 rotates together with the retaining disk 20. When the retaining disk 20 is rotated during grinding of the substrate W, the visor portion 71 rotates, and under centrifugal force, the grinding fluid adhering to the visor portion 71 is blown radially outward. Therefore, the deposition of grinding chips mixed with the grinding fluid can be suppressed, and the deposition of grinding chips around the retaining disk 20 can be suppressed. As a result, contamination of operators or robots can be prevented during maintenance such as changing the retaining disk 20 or the grinding tool D. Furthermore, the deposition of grinding chips can be prevented from peeling off and adhering to the retaining disk 20 or the substrate W.

[0079] A spacer 28 is provided between the awning portion 71 of the retaining disc cover 70 and the flange 23 of the retaining disc 20. Multiple spacers 28 are spaced apart circumferentially on the flange 23. The awning portion 71 is mounted on the multiple spacers 28. Alternatively, the spacers 28 may be integrated with the awning portion 71; in this case, the spacers 28 are mounted on the flange 23, and the shank of the bolt 29 (described later) is screwed into the bolt hole of the flange 23.

[0080] The spacer 28 forms a gap between the awning portion 71 and the flange 23. Compared to the case without a gap, the thickness of the awning portion 71 can be reduced, thus making the awning portion 71 lighter. In addition, space can be ensured between the awning portion 71 and the flange 23 for the head of the bolt 24.

[0081] The spacer 28 has bolt holes on its upper surface. A bolt 29, which secures the awning 71 to the spacer 28, is screwed into these bolt holes. The head of the bolt 29 presses down on the awning 71 from above. A groove 71b extending radially along the retaining disc 20 is formed on the upper surface of the awning 71. This groove 71b receives the head of the bolt 29, which presses down on the bottom surface of the groove 71b from above. The head of the bolt 29 and the bottom surface of the groove 71b are horizontal.

[0082] The upper surface of the awning portion 71 is inclined, while the lower surface of the awning portion 71 is horizontal. If the lower surface of the awning portion 71 is horizontal, the awning portion 71 can be stably placed on a plurality of spacers 28. The number of spacers 28 is preferably three or more.

[0083] The retaining cover 70 includes an outer cylindrical portion 77 extending downward from the periphery of the awning portion 71. The outer cylindrical portion 77... Figure 5 The outer cylinder 77 extends directly downwards, but it can also extend diagonally downwards. The outer cylinder 77 extends to a position lower than the upper end of the inner cylinder 67 of the platform cover 60 (described later), surrounding the inner cylinder 67. The inner cylinder 67 and the outer cylinder 77 together form a labyrinth that inhibits the intrusion of grinding fluid.

[0084] The junction between the visor portion 71 and the outer cylinder portion 77 has, for example, a chamfered shape and a curved shape. In the case of a zigzag-shaped junction, the surface tension of the droplets prevents them from crossing the junction. As a result, annular fluid accumulation is easily formed. If the junction between the visor portion 71 and the outer cylinder portion 77 has a curved shape, the droplets can easily cross the junction, and the grinding fluid can be easily discharged. Therefore, it is possible to suppress the annular deposition of grinding chips mixed in the grinding fluid.

[0085] like Figure 5 As shown, the grinding apparatus 1 has a stage cover 60 that rotates together with the stage 10. The stage cover 60 has an inclined portion 61 that tilts downwards the further away from the rotation center line R1 of the stage 10.

[0086] The inclined portion 61 is positioned below the upper surface of the holding platform 21 of the holding disc 20, and is positioned above the platform 10. Unlike the horizontal flat plate portion, the inclined portion 61 allows the grinding fluid to be discharged obliquely downwards under the action of gravity. This helps to suppress the deposition of grinding chips mixed with the grinding fluid.

[0087] The inclined portion 61, for example, has a conical shape with a fixed height in the circumferential direction of the platform 10. When the inclined portion 61 has a conical shape, such as... Figure 3 As indicated by the arrow, the grinding fluid can be discharged radially, which can suppress the deposition of grinding chips around the retaining disk 20.

[0088] Furthermore, the inclined portion 61 can also have a pyramidal shape. However, when the inclined portion 61 has a pyramidal shape, it forms... Figure 3 The groove G is indicated by a double-dotted line. The retaining disk 20 is located at the bottom of the groove G. Grinding fluid tends to accumulate near the retaining disk 20, and grinding chips mixed with the grinding fluid tend to deposit.

[0089] like Figure 5 As shown, the inclined portion 61 forms an opening 61a between its top and base for the rotary table 25 to enter. The openings 61a are formed for each rotary table 25, and a plurality of them are formed at intervals around the rotation center line R1 of the table 10. The plurality of openings 61a are formed, for example, at equal intervals.

[0090] The platform cover 60 includes an inner cylindrical portion 67 that rises upward from the opening edge of the opening 61a of the inclined portion 61. The inner cylindrical portion 67... Figure 5 It can stand upright directly upwards, but it can also stand diagonally upwards. The upper edge of the inner cylinder 67 is horizontal throughout the circumference. The inner cylinder 67 prevents grinding fluid from entering the opening 61a.

[0091] like Figure 6 As shown in (A), the inner cylinder portion 67 includes a first arcuate cylinder portion 67a, a second arcuate cylinder portion 67b, and a connecting portion 67c. The first arcuate cylinder portion 67a is fixed to the inclined portion 61. The second arcuate cylinder portion 67b is detachably connected to the first arcuate cylinder portion 67a. The connecting portion 67c connects the first arcuate cylinder portion 67a and the second arcuate cylinder portion 67b into a ring shape.

[0092] The connecting portion 67c includes, for example, a connecting plate 67c1 and a bolt 67c2. The connecting plate 67c1 is, for example, fixed to the inner circumferential surface of the second arcuate cylindrical portion 67b and extends to the inner circumferential surface of the first arcuate cylindrical portion 67a. The shank of the bolt 67c2 passes through a through hole in the first arcuate cylindrical portion 67a and is screwed into a bolt hole in the connecting plate 67c1. The head of the bolt 67c2 presses against the first arcuate cylindrical portion 67a from the radially outward side.

[0093] Furthermore, the construction of the connecting portion 67c is not particularly limited. For example, the connecting plate 67c1 may be fixed to the inner circumferential surface of the first arcuate cylindrical portion 67a and extend to the inner circumferential surface of the second arcuate cylindrical portion 67b. In this case, the shank of the bolt 67c2 passes through the through hole of the second arcuate cylindrical portion 67b and is screwed into the bolt hole of the connecting plate 67c1. The head of the bolt 67c2 presses against the second arcuate cylindrical portion 67b from the radially outward side.

[0094] Regardless, the second arc-shaped cylindrical section 67b can be disassembled and installed by loosening and tightening bolt 67c2. Figure 6 As can be seen from (B), the retaining plate 20 can be easily replaced by disassembling the second arc-shaped cylindrical part 67b.

[0095] like Figure 5 As shown, the second arc-shaped cylindrical portion 67b is positioned radially outward from the stage 10 compared to the first arc-shaped cylindrical portion 67a. Furthermore, at least a portion of the lower edge of the second arc-shaped cylindrical portion 67b is positioned below the upper surface of the rotary table 25.

[0096] As a result, if the second arc-shaped cylindrical section 67b is disassembled, it is possible to achieve the following: Figure 7 The retaining plate 20, which is placed on the upper surface of the rotary table 25, is pulled out laterally as shown. This is more effective when the clamping force between the retaining plate 20 and the rotary table 25 is strong enough that the retaining plate 20 cannot be peeled upwards.

[0097] like Figure 5 As shown, the inner cylinder portion 67 may also include a third arcuate cylinder portion 67d, which is used to house the second arcuate cylinder portion 67b. The third arcuate cylinder portion 67d may also be fixed to the inclined portion 61 and integrated with the first arcuate cylinder portion 67a.

[0098] The inner cylinder portion 67 may also include a positioning alignment portion 67e, which aligns the second arcuate cylinder portion 67b with the third arcuate cylinder portion 67d. The positioning alignment portion 67e is, for example, fixed to the inner circumferential surface of the second arcuate cylinder portion 67b, inserted into the inner side of the third arcuate cylinder portion 67d, and contacts the inner circumferential surface of the third arcuate cylinder portion 67d, thereby aligning the second arcuate cylinder portion 67b with the third arcuate cylinder portion 67d.

[0099] The platform cover 60 has a cylindrical portion 63 extending downward from the lower edge of the inclined portion 61. The cylindrical portion 63... Figure 5 It extends directly downwards, but it can also extend diagonally downwards. The cylindrical portion 63 causes the grinding fluid to fall outside the platform 10. The outer diameter of the cylindrical portion 63 is larger than the diameter of the platform 10.

[0100] The junction between the inclined portion 61 and the cylindrical portion 63 has, for example, a chamfered shape and a curved shape. Compared to a junction with a zigzag shape, the liquid can easily cross this junction, and the grinding fluid can be easily discharged. Therefore, it is possible to suppress the ring-shaped deposition of grinding chips mixed in the grinding fluid.

[0101] The inclined portion 61 forms an opening 61b at its top for the fixed shaft 11 to pass through. The platform cover 60 has a central cylindrical portion 69 that rises upwards from the opening edge of the opening 61b of the inclined portion 61. The central cylindrical portion 69... Figure 5 It can stand upright directly upwards, but it can also stand diagonally upwards. The central cylindrical portion 69 prevents grinding fluid from seeping into the opening 61b.

[0102] The stage cover 60 is divided into multiple partition covers in the circumferential direction of the stage 10. The number of partition covers is the same as the number of holding disks 20. Rotating partition walls 15 are arranged between adjacent partition covers in the circumferential direction.

[0103] Multiple partition covers are installed on the platform 10 in a manner that allows for individual removal. During maintenance, only the partition covers need to be removed individually, without having to disassemble the entire platform cover 60, thus improving workability.

[0104] The grinding apparatus 1 includes a base cover 90. The base cover 90 has a horizontal disc portion 91. The disc portion 91 is disposed below the table cover 60 and above the table 10, and is arranged concentrically with the table 10. The diameter of the disc portion 91 is larger than the diameter of the table 10.

[0105] The disk portion 91 forms an opening 91a around the rotation center line R1 of the stage 10, through which the rotation axis 26 of the holding disk 20 passes. Multiple openings 91a are formed at equal intervals around the rotation center line R1 of the stage 10.

[0106] The base cover 90 includes an inner cylinder portion 93 that rises upward from the opening edge of the opening portion 91a. The inner cylinder portion 93... Figure 5 It can stand upright directly upwards, but it can also stand diagonally upwards. The rotating shaft 26 passes through the inner cylinder 93.

[0107] The rotating shaft 26 extends vertically downward from the rotation center of the rotary table 25. An outer cylindrical portion 27 extending downward is provided around the periphery of the rotary table 25. The outer cylindrical portion 27... Figure 5 It extends directly downwards, but it can also extend diagonally downwards.

[0108] The outer cylinder portion 27 extends to a position slightly below the upper end of the inner cylinder portion 93 of the base cover 90, surrounding the inner cylinder portion 93. The inner cylinder portion 93 and the outer cylinder portion 27 can form a labyrinth that inhibits the intrusion of grinding fluid.

[0109] As described above, a plurality of openings 91a are arranged at equal intervals around the rotation center line R1 of the platform 10. A rotation partition wall 15 is arranged between adjacent openings 91a in the circumferential direction of the platform 10. The rotation partition wall 15 is provided on the disk portion 91.

[0110] The base cover 90 has a cylindrical portion 94 extending downward from the periphery of the disc portion 91. The cylindrical portion 94... Figure 5 It extends directly downwards, but it can also extend diagonally downwards.

[0111] The junction between the disc portion 91 and the cylindrical portion 94 has, for example, a chamfered shape and a curved shape. Compared to a zigzag shape, droplets can more easily cross this junction, and the grinding fluid can be more easily discharged. Therefore, it is possible to suppress the ring-shaped deposition of grinding chips mixed in the grinding fluid.

[0112] like Figure 5 As shown, the grinding apparatus 1 includes a nozzle 51 that supplies cleaning fluid to the inclined portion 61 between the top of the inclined portion 61 of the stage 60 and the retaining plate 20. The nozzle 51 supplies the cleaning fluid to the inclined portion 61 from above. The nozzle 51 may also be located in the central cylinder portion 69. The cleaning fluid is, for example, pure water. After being supplied to the inclined portion 61, the cleaning fluid flows downwards under gravity. Using the cleaning fluid, a wider area of ​​the inclined portion 61 can be cleaned, and the deposition of grinding chips around the retaining plate 20 can be suppressed. The nozzle 51 may also supply cleaning fluid to the inclined portion 61 at a position that allows the cleaning fluid to reach the top of the inclined portion 61. The entire inclined portion 61 can be cleaned from the top to the base.

[0113] For example, during the grinding of the substrate W, nozzle 51 sprays cleaning fluid to wash away the grinding fluid and grinding chips adhering to the inclined portion 61. Nozzle 51 is provided not only in the primary grinding chamber B1, but also in the secondary grinding chamber B2 and the tertiary grinding chamber B3. Nozzle 51 may also be provided in the feed and discharge chamber B0. Nozzle 51 may also spray cleaning fluid at times other than during the grinding of the substrate W.

[0114] The inclined portion 61 of the platform cover 60 forms an opening 61b at its top for the fixed shaft 11 to pass through. The central cylinder portion 69 rises from the opening edge of the opening 61b, and the nozzle 51 is disposed radially outward of the central cylinder portion 69. This prevents cleaning fluid from seeping into the inner side of the central cylinder portion 69.

[0115] The grinding apparatus 1 includes a measuring device 95 for measuring the thickness of a substrate W. The measuring device 95 includes a nozzle 51. Flow paths L1 and L2 for cleaning fluid are formed inside the measuring device 95. Flow path L2 passes through the base end of at least one of the first arm 95c and the second arm 95d (described later). The cleaning fluid passes through flow path L2, absorbs heat from the first height sensor 95a via the first arm 95c, and is ejected from the nozzle 51. Alternatively, the cleaning fluid passes through flow path L2, absorbs heat from the second height sensor 95b via the second arm 95d, and is ejected from the nozzle 51. At least one of the first height sensor 95a and the second height sensor 95b can be cooled using the cleaning fluid. Furthermore, the cooling flow path L2 can be formed independently of the flow path L1 for the nozzle.

[0116] The measuring device 95 includes, for example, a first height sensor 95a for measuring the height of the substrate W and a second height sensor 95b for measuring the height of the holding disk 20. Based on the difference between the height of the substrate W and the height of the holding disk 20, the thickness of the substrate W can be measured. Furthermore, the measuring device 95... Figure 5 It can be a contact type, but it can also be a non-contact type.

[0117] The measuring device 95 includes a first arm 95c holding a first height sensor 95a, a second arm 95d holding a second height sensor 95b, and a bracket 95e holding the first arm 95c and the second arm 95d. A nozzle 51 is provided on the lower surface of the bracket 95e.

[0118] The bracket 95e of the measuring instrument 95 is mounted on the upper surface of the fixed shaft 11 and protrudes radially outward from the fixed shaft 11. The nozzle 51 is provided on the lower surface of the bracket 95e, which protrudes radially outward from the fixed shaft 11, and supplies cleaning fluid to the inclined portion 61.

[0119] like Figure 8 As shown, multiple supply ports 51a of the nozzle 51 are provided at intervals along the circumference (rotation direction) of the stage 60. Multiple supply ports 51a can also be provided in a single chamber (e.g., primary grinding chamber B1). Using multiple supply ports 51a, a wider circumferential area of ​​the inclined portion 61 of the stage 60 can be cleaned simultaneously. Furthermore, the supply ports 51a of the nozzle 51 are arc-shaped slits along the circumference of the stage 60. Cleaning fluid can be supplied near the top of the inclined portion 61 of the stage 60. Additionally, the supply ports 51a of the nozzle 51 can also be straight slits or circular holes.

[0120] Furthermore, at the base of the inclined portion 61, the surface tension of the droplet prevents it from crossing the base. As a result, ring-shaped liquid accumulation is easily formed, and ring-shaped dirt easily adheres to it.

[0121] Therefore, the grinding apparatus 1 includes nozzles 52-1 and 52-2, which supply cleaning fluid from above to the base of the inclined portion 61 of the stage cover 60. The cleaning fluid is, for example, pure water. The cleaning fluid rinses away the grinding fluid contaminated by grinding chips and inhibits the adhesion of annular dirt.

[0122] Nozzle 52-1 is located, for example, near the boundary between the primary grinding chamber B1 and the feed / exit chamber B0. This boundary refers to the area within 50 mm of the fixed partition wall 45 that serves as the boundary. It is sufficient that at least a portion of the nozzle 52-1's outlet is located within this area.

[0123] On the other hand, the nozzle 52-2 is located near the boundary between the tertiary grinding chamber B3 and the feed / exit chamber B0. This boundary refers to the area within 50 mm of the fixed partition wall 45 that serves as the boundary. It is sufficient that at least a portion of the nozzle 52-2's outlet is located within this range.

[0124] During the clockwise rotation of the rotary table 10 when viewed from above by the control unit 16, cleaning fluid is supplied from the nozzle 52-1 disposed in the primary grinding chamber B1 to the base of the inclined portion 61 of the table cover 60. The base of the inclined portion 61 can be cleaned just before it moves from the primary grinding chamber B1 to the feed-in / feed-out chamber B0, preventing dirt from being carried into the feed-in / feed-out chamber B0.

[0125] On the other hand, during the period when the control unit 16 rotates the rotary table 10 counterclockwise when viewed from above, cleaning fluid is supplied from the nozzle 52-2 disposed in the tertiary grinding chamber B3 to the base of the inclined portion 61 of the table cover 60. Before the base of the inclined portion 61 moves from the tertiary grinding chamber B3 to the feed-in / feed-out chamber B0, the base of the inclined portion 61 can be cleaned, preventing dirt from being carried into the feed-in / feed-out chamber B0.

[0126] like Figure 8 As shown, the grinding apparatus 1 includes an exhaust box 43 located outside the housing 40, from which gas is discharged. The exhaust box 43 is connected via a pipe 44 to a suction source (not shown). The suction source is, for example, a vacuum pump or an ejector. The suction source may also be part of the factory facility. The pipe 44 is, for example, located at the top 43a of the exhaust box 43. The exhaust box 43 uses the suction force of the suction source to discharge gas from the inside of the housing 40, creating a negative pressure inside the housing 40 compared to the outside, thus suppressing the leakage of grinding chips and grinding fluid.

[0127] Three exhaust boxes 43 discharge gas independently from the three grinding chambers B1 to B3, creating a negative pressure in the three grinding chambers B1 to B3 relative to the outside of the housing 40. The gas pressure in the feed-in / feed-out chamber B0 is higher than the gas pressure in the grinding chambers B1 to B3. This pressure difference restricts the dispersion of grinding chips and grinding fluid from the grinding chambers B1 to B3 to the feed-in / feed-out chamber B0.

[0128] Furthermore, the number of exhaust boxes 43 and the number of grinding chambers are not limited to three. Additionally, the number of exhaust boxes 43 and the number of pipes 44 may not be the same. For example, a single pipe 44 may span and connect two adjacent exhaust boxes 43.

[0129] In addition, when the exhaust box 43 discharges gas from inside the housing 40, it also discharges droplets of grinding fluid from inside the housing 40. Moreover, grinding chips generated during grinding are mixed into the droplets of grinding fluid.

[0130] Therefore, as Figure 9 As shown, the side panel 42 of the housing 40 includes a liquid receiving section 42a, an exhaust port 42b, and a return port 42c to prevent grinding fluid contaminated by grinding chips from being discharged to the outside of the grinding apparatus 1 along with the gas.

[0131] The liquid receiving section 42a is located at the same height as the substrate W held in the holding plate 20, and receives the grinding fluid that is horizontally dispersed from the upper surface of the substrate W. The liquid receiving section 42a restricts a large amount of grinding fluid from entering the exhaust box 43.

[0132] The vent 42b is located above the liquid receiving section 42a, for example, directly above the liquid receiving section 42a. After the grinding fluid collides with the liquid receiving section 42a, it falls downwards under the influence of gravity, so it hardly enters the vent 42b.

[0133] The exhaust port 42b is connected to the interior of the exhaust box 43. The exhaust box 43 discharges gas from the interior of the housing 40 through the exhaust port 42b. Droplets of grinding fluid are mixed into this gas.

[0134] The exhaust box 43 separates the grinding fluid droplets from the gas inside. The grinding fluid droplets, having a density greater than that of the gas, separate from the gas under the influence of gravity and other forces. The separated grinding fluid then falls.

[0135] The return port 42c is located below the liquid receiving section 42a, for example, directly below the liquid receiving section 42a. The return port 42c allows the grinding fluid separated from the gas inside the exhaust box 43 to return to the interior of the housing 40. This prevents the grinding fluid contaminated by grinding chips from being discharged to the outside of the grinding apparatus 1 along with the gas.

[0136] The exhaust box 43 has an inclined surface 43b that guides the grinding fluid separated from the gas inside the exhaust box 43 obliquely downward toward the return port 42c of the side panel 42. The more downward the inclined surface 43b goes, the closer it is to the side panel 42. The grinding fluid flows down along the inclined surface 43b. This flow helps to prevent dirt from adhering to the inclined surface 43b.

[0137] The inclined surface 43b of the exhaust box 43 extends downwards from a position higher than the exhaust port 42b of the side panel 42 to a position at the same height as the return port 42c of the side panel 42, getting closer and closer to the side panel 42. After passing through the exhaust port 42b of the side panel 42 along with the gas, the grinding fluid droplets adhere to the inclined surface 43b of the exhaust box 43 and flow down along the inclined surface 43b.

[0138] The grinding device 1 may also include a nozzle 53 that supplies cleaning fluid to the interior of the housing 40 via the interior of the exhaust box 43. The cleaning fluid is, for example, pure water such as DIW. After being supplied to the interior of the exhaust box 43, the cleaning fluid passes through the return port 42c of the side panel 42 and is supplied to the interior of the housing 40. Unlike grinding fluid, the cleaning fluid does not contain grinding chips or other contaminants, thus enabling the cleaning of both the interior of the exhaust box 43 and the interior of the housing 40.

[0139] The nozzle 53 is provided, for example, on the inclined surface 43b of the exhaust box 43. The cleaning fluid flows down along the inclined surface 43b. This flow helps to prevent dirt from adhering to the inclined surface 43b. The nozzle 53 may or may not protrude upward from the inclined surface 43b.

[0140] In addition, such as Figure 8 As shown, when viewed from above, the gap between the circular platform 60 and the side panel 42 becomes narrowest at the junction between adjacent chambers (e.g., B1 and B2, or B0 and B3). This narrower gap is prone to clogging with grinding chips.

[0141] Furthermore, without the stage cover 60, when viewed from above, the gap between the stage 10 and the side panel 42 becomes the narrowest at the junction between adjacent chambers. This narrower gap is prone to clogging with grinding chips.

[0142] Therefore, in this embodiment, the return port 42 of the side panel 42 is disposed near the boundary between adjacent chambers (e.g., B1 and B2, or B0 and B3), and near the fixed partition wall 45. "Near the fixed partition wall 45" refers, for example, to a range within 50 mm of the fixed partition wall 45. It is sufficient that at least a portion of the return port 42c is located within this range.

[0143] The return port 42c of the side panel 42 is located near the boundary between adjacent chambers (e.g., B1 and B2, or B0 and B3), thereby supplying cleaning fluid into the gap between the stage cover 60 and the side panel 42, forming a fluid flow. This flow is used to suppress grinding chip clogging.

[0144] like Figure 9 As shown in (B), when viewed from the front of the side panel 42, the nozzle outlet 53a of the nozzle 53 can also be positioned as close as possible to the boundary between adjacent chambers, that is, as close as possible to the fixed partition wall 45.

[0145] For example, when viewed from the front of the side panel 42, the distance between the fixed partition wall 45 and the nozzle 53 outlet 53a and the distance between the fixed partition wall 45 and the return port 42c can be the same. Cleaning fluid can be supplied to the interior of the housing 40 from the end of the return port 42c closest to the fixed partition wall 45.

[0146] Furthermore, although not shown, a nozzle for supplying cleaning fluid to the interior of the housing 40 may be provided in the liquid receiving portion 42a of the side panel 42. This nozzle may be located, for example, at the upper part of the liquid receiving portion 42a. After being ejected from the nozzle, the cleaning fluid flows down along the liquid receiving portion 42a, washing away grinding debris adhering to the liquid receiving portion 42a.

[0147] like Figure 8 and Figure 10 As shown, the housing 40 includes a disk 46 located below a plurality of retaining disks 20, which receives falling grinding fluid and grinding chips. The disk 46 also receives cleaning fluid. Hereinafter, grinding fluid and cleaning fluid will be collectively referred to as liquids. Additionally, liquid contaminated by grinding chips will be referred to as contaminated liquid. The disk 46 has two inclined surfaces 210 and 220 on its upper surface.

[0148] like Figure 10 As shown in (A), the two inclined surfaces 210 and 220 combine to form a mountain shape, sloping downwards the further away from the boundary line BL between the two adjacent chambers B0 and B1 and the remaining two chambers B2 and B3. The two inclined surfaces 210 and 220 sandwich the boundary line BL, causing the sewage to flow down to both sides.

[0149] According to this embodiment, the two inclined surfaces 210 and 220 are combined to form a mountain shape. Therefore, compared to the case with only one inclined surface, if the height difference between the inclined surfaces is the same, the horizontal distance between the inclined surfaces is shorter and the slope of the inclination is steeper. As a result, the waste liquid can flow down more easily. Therefore, the flow of grinding chips and grinding fluid in the disc 46 can be improved.

[0150] like Figure 10 As shown in (A), the disk 46 has two flow channels 230 and 240 along the lower edges 211 and 221 of the two inclined surfaces 210 and 220. After flowing down the two inclined surfaces 210 and 220, the waste liquid enters the two flow channels 230 and 240.

[0151] like Figure 10 (B) and Figure 10 As shown in (C), each flow channel 230, 240 has a guide surface 231, 241 at its bottom that slopes downward from one end of its lower edge 211, 221 toward the other end. The guide surface 231, 241 can be used to collect waste liquid.

[0152] like Figure 10 As shown in (B), the flow channel 230 has a guide surface 231 at its bottom that slopes downward from the feed-in / out chamber B0 toward the primary grinding chamber B1. By utilizing the slope of the guide surface 231, it is possible to prevent primary grinding chips contained in the sludge from entering the feed-in / out chamber B0 from the primary grinding chamber B1, and to keep the feed-in / out chamber B0 clean.

[0153] In addition, such as Figure 10 As shown in (B), the flow channel 230 may also have a guide surface 232 at its bottom that is inclined in the opposite direction to the guide surface 231. The guide surface 232 is shorter than the guide surface 231 and is located at one end of the primary grinding chamber B1 on the side opposite to the feed-in and feed-out chamber B0.

[0154] like Figure 10As shown in (C), the flow channel 240 has a guide surface 241 at its bottom that slopes downward from the tertiary grinding chamber B3 toward the secondary grinding chamber B2. By utilizing the slope of the guide surface 241, it is possible to suppress the intrusion of larger secondary grinding chips from the secondary grinding chamber B2 into the tertiary grinding chamber B3, and to suppress the roughness of the grinding surface after tertiary grinding.

[0155] In addition, such as Figure 10 As shown in (C), the flow channel 240 may also have a guide surface 242 at its bottom that is inclined in the opposite direction to the guide surface 241. The guide surface 242 is shorter than the guide surface 241 and is located at one end of the secondary grinding chamber B2 on the side opposite to the tertiary grinding chamber B3.

[0156] Each flow channel 230, 240 includes a discharge port 233, 243 at its lowest point on the bottom of the channel to discharge the waste liquid. Pipes 250, 260 extending downward from the discharge ports 233, 243 are connected to the discharge ports 233, 243.

[0157] The wastewater flows down along guide surfaces 231 and 241 and is discharged from outlets 233 and 243 to pipes 250 and 260. Since outlets 233 and 243 are located at the lowest point, the collected wastewater can be discharged efficiently.

[0158] like Figure 11 As shown, the tool drive unit 30 includes a movable part 31 for mounting the grinding tool D and a lifting part 35 for raising and lowering the movable part 31. The lifting part 35 is not opposite to the lower edges 211, 221 of the inclined surfaces 210, 220, but rather to the mountain-shaped inclined edges 212, 222 of the inclined surfaces 210, 220. The lifting part 35 does not face the flow channels 230, 240, thus facilitating maintenance of the flow channels 230, 240.

[0159] As described above, grinding fluid and cleaning fluid are supplied to the interior of housing 40. Grinding chips flow into outlets 233 and 243 along with these liquids. As a result, outlets 233 and 243 may become clogged.

[0160] Therefore, as Figure 12 As shown, the grinding apparatus 1 includes first liquid level sensors 80-1 and 80-2 located inside the housing 40. The first liquid level sensors 80-1 and 80-2 detect the liquid level of liquid remaining inside the housing 40. When the detected liquid level exceeds a preset height, the control unit 16 determines that the drain outlets 233 and 243 are blocked.

[0161] Furthermore, the grinding apparatus 1 includes sensor covers 81-1 and 81-2, which are located between the holding plate 20 and the first liquid level sensors 80-1 and 80-2. The sensor covers 81-1 and 81-2 block contaminants flowing from the substrate W held in the holding plate 20 to the first liquid level sensors 80-1 and 80-2. Therefore, it is possible to suppress the adhesion of contaminants to the first liquid level sensors 80-1 and 80-2, and to prevent malfunctions of the first liquid level sensors 80-1 and 80-2. In addition, it is possible to reduce the impact applied to the first liquid level sensors 80-1 and 80-2, and to suppress malfunctions of the first liquid level sensors 80-1 and 80-2.

[0162] The housing 40 includes four side panels 42-1, 42-2, 42-3, and 42-4 located on the side of the retaining disk 20. These side panels 42 are combined to form a rectangle, creating four corners CR0 to CR3. CR0 is the corner of the feed-in / feed-out chamber B0, CR1 is the corner of the primary grinding chamber B1, CR2 is the corner of the secondary grinding chamber B2, and CR3 is the corner of the tertiary grinding chamber B3.

[0163] The first liquid level sensor 80-1 is located at corner CR1, and the other first liquid level sensor 80-2 is located at another corner CR2. By configuring the first liquid level sensors 80-1 and 80-2 at corners CR1 and CR2, interference with other components can be prevented.

[0164] When viewed from above, the sensor cover 81-1 has an inclined plate 81a-1, which is inclined relative to the two side panels 42-1 and 42-2 forming the angle CR1. Furthermore, the first liquid level sensor 80-1 is located in the space enclosed by the two side panels 42-1 and 42-2 and the inclined plate 81a-1. The inclined plate 81a-1 conceals the angle CR1, thereby preventing dirt from accumulating in the angle CR1.

[0165] Furthermore, when viewed from above, the sensor cover 81-2 has an inclined plate 81a-2, which is inclined relative to the two side panels 42-2 and 42-3 forming the angle CR2. Moreover, the first liquid level sensor 80-2 is located in the space enclosed by the two side panels 42-2 and 42-3 and the inclined plate 81a-2. The inclined plate 81a-2 conceals the angle CR2, thereby preventing dirt from accumulating in the angle CR2.

[0166] When viewed from above, the first liquid level sensor 80-1 overlaps with the flow channel 230, and the other first liquid level sensor 80-2 overlaps with the other flow channel 240. The first liquid level sensors 80-1 and 80-2 can be located either inside the flow channels 230 and 240 or above them. Regardless of the location, they can detect the liquid level at the point where liquid accumulates in the flow channels 230 and 240.

[0167] When viewed from above, the first liquid level sensors 80-1 and 80-2 are located near the outlets 233 and 243. By positioning the first liquid level sensors 80-1 and 80-2 near the outlets 233 and 243, blockages in the outlets 233 and 243 can be reliably detected. "Near" the outlets 233 and 243 is, for example, a range within 50 mm of the outlets 233 and 243.

[0168] The grinding apparatus 1 includes second level sensors 82-1 and 82-2, independent of the first level sensors 80-1 and 80-2, which detect the level of liquid remaining inside the housing 40. The first level sensor 80-1 and the second level sensor 82-1 are positioned at the same angle CR1 and detect the same level. Similarly, the first level sensor 80-2 and the second level sensor 82-2 are positioned at the same angle CR2 and detect the same level. This allows for dual detection of the same level using both sensors. Even if one sensor malfunctions, the remaining sensor can still detect the level. Furthermore, the second level sensors 82-1 and 82-2 can also detect levels higher than the detection range of the first level sensors 80-1 and 80-2.

[0169] Next, refer to Figure 13 This describes a set of level sensors, namely, level sensor 80-1 and level sensor 82-1. Furthermore, another set of level sensors, namely, level sensor 80-2 and level sensor 82-2, is similarly constructed, therefore their description is omitted.

[0170] The grinding apparatus 1 has a vertical tube 83 on the outside of the housing 40 that communicates with the inside of the housing 40. A horizontal tube 86 extending from the lower end of the vertical tube 83 is inserted into the interior of the flow channel 230, for example. A horizontal tube 87 extending from the upper end of the vertical tube 83 is positioned, for example, above the upper panel 41 of the housing 40.

[0171] External air enters the interior of the plumb tube 83. Therefore, the liquid level inside the plumb tube 83 is the same as the liquid level inside the housing 40. A second liquid level sensor 82-1 is installed in the plumb tube 83 to detect the liquid level inside the plumb tube 83.

[0172] The second liquid level sensor 82-1 differs from the first liquid level sensor 80-1 in that it is disposed outside the housing 40. Therefore, it is possible to prevent contaminants from splashing onto the second liquid level sensor 82-1 and to prevent malfunctions and failures of the second liquid level sensor 82-1.

[0173] The first liquid level sensor 80-1 includes a displacement gauge for measuring the displacement of the liquid level. For example, the first liquid level sensor 80-1 has a float 80a that rises and falls with changes in the liquid level, a guide 80b for the float 80a, and a displacement gauge 80c for measuring the displacement of the float 80a. Furthermore, the displacement gauge is not limited to a float type. The displacement gauge continuously measures the height of the liquid level within a specified range.

[0174] On the other hand, the second liquid level sensor 82-1 includes a switch for detecting when the liquid level reaches a set value. The switch is, for example, a proximity switch. The type of proximity switch is not particularly limited; for example, it can be optical. An optical proximity switch detects the transmitted light from a transparent plumb line 83, and detects when the liquid level reaches the set value based on changes in the amount of light. Alternatively, the proximity switch can also be capacitive. In this case, the plumb line 83 can also be opaque. By using a sensor of a different type than the first liquid level sensor 80-1 as the second liquid level sensor 82-1, it is possible to avoid simultaneous malfunctions or failures in both sensors.

[0175] The second liquid level sensor 82-1 includes a switch for detecting when the liquid level reaches a set value. This set value can also be lower than the top 201 of the two inclined surfaces 210, 220 that form a mountain shape (see reference). Figure 10 The height H of (A)). Before the flow along inclined surfaces 210 and 220 disappears and grinding chips begin to settle, blockage of outlets 233 and 243 can be detected.

[0176] like Figure 12 As shown, the grinding apparatus 1 may also have a corner cover 84 with an independent coverage angle CR3 relative to the sensor covers 81-1 and 81-2. The corner cover 84 has an inclined plate 84a that is inclined relative to the two side panels 42-3 and 42-4 forming the corner CR3. By using the inclined plate 84a to hide the corner CR3, it is possible to prevent dirt from accumulating in the corner CR3. The corner cover 84 may also be omitted from the feed inlet / outlet chamber B0.

[0177] Alternatively, the grinding apparatus 1 may also have a second corner cover 85 covering the angle between the side panel 42 and the fixed partition wall 45. The second corner cover 85 has a second inclined plate 85a, which is inclined relative to both the side panel 42 and the fixed partition wall 45. By using the second inclined plate 85a to conceal the angle, it is possible to prevent dirt from accumulating in the angle. The second corner cover 85 is provided in the primary grinding chamber B1, the secondary grinding chamber B2, and the tertiary grinding chamber B3. The second corner cover 85 may also not be provided in the feed-in / feed-out chamber B0.

[0178] like Figure 14 As shown in (A), the grinding apparatus 1 includes an outer casing 300 forming the outer surface of the grinding apparatus 1. The outer casing 300 internally houses a stage 10, a holding disc 20, a holding disc drive unit 19, a tool drive unit 30, a housing 40, and a recovery unit 320. The recovery unit 320 recovers grinding chips. Grinding chips, for example, flow into the recovery unit 320 along with liquids such as grinding fluid. The recovery unit 320 separates the liquid from the grinding chips, discharges the liquid, and leaves the grinding chips. Details of the recovery unit 320 will be described later.

[0179] The outer casing 300 has a first opening 301 and a second opening 302. The first opening 301 allows the operator or robot to access the holding disc 20 or the tool drive unit 30 from the outside. On the other hand, the second opening 302 allows the operator or robot to access the retraction unit 320 from the outside.

[0180] The grinding apparatus 1 has a first gate 311 for opening and closing a first opening 301 and a second gate 312 for opening and closing a second opening 302 independently of the first gate 311. An operator or a work robot operates the first gate 311 to open and close the first opening 301. Similarly, an operator or a work robot operates the second gate 312 to open and close the second opening 302.

[0181] According to this embodiment, a first opening 301 and a second opening 302 are formed on the outer surface of the grinding apparatus 1. The second opening 302 is formed closer to the collection section 320 than the first opening 301. As a result, when the operator or the robot contacts the collection section 320, it is not necessary to operate the first door 311 or open the first opening 301. Therefore, the operator or the robot does not need to contact the holding plate 20 or the tool drive section 30. Thus, while the holding plate 20 and the grinding tool D are driven, the grinding chips can be removed to the outside of the grinding apparatus 1 without interrupting the grinding of the substrate W. In other words, the grinding chips can be removed to the outside of the grinding apparatus 1 during the grinding of the substrate W.

[0182] The first opening 301 and the second opening 302 are formed, for example, on the same side facing the same direction as the grinding apparatus 1. Alternatively, the first opening 301 and the second opening 302 may also be formed on the opposite side facing the grinding apparatus 1, and there may be multiple first openings 301 and second openings 302. Furthermore, there may also be multiple collection sections 320. The collection section 320 is located at a location that is more than... Figure 13 The grinding chips falling from the discharge ports 233 and 243 of the housing 40 are collected at the lower part of the housing 40.

[0183] like Figure 14 As shown in (A), the grinding apparatus 1 includes a door sensor 321, which detects the opening of the first opening 301 via the first door 311. The door sensor 321 is not particularly limited; for example, it could be a proximity switch. When the door sensor 321 detects the opening of the first opening 301, it sends a signal indicating this opening to the control unit 16 (see reference 16). Figure 1 )send.

[0184] During the operation of the holding disc 20 and the grinding tool D, when the opening of the first opening 301 is detected by the door sensor 321, the control unit 16 stops the operation of the holding disc 20 and the grinding tool D. Similarly, during the operation of the stage 10, when the opening of the first opening 301 is detected by the door sensor 321, the control unit 16 stops the operation of the stage 10. This prevents contact between objects during the operation and the operator or the robot.

[0185] On the other hand, even when the second gate 312 opens the second opening 302 during the driving of the holding disc 20 and the grinding tool D, the control unit 16 continues to drive the holding disc 20 and the grinding tool D. Similarly, even when the second gate 312 opens the second opening 302 during the driving of the stage 10, the control unit 16 continues to drive the stage 10. The grinding of the substrate W does not need to be interrupted in order to remove grinding chips to the outside of the grinding apparatus 1.

[0186] As described above, even if the second door 312 opens the second opening 302, the control unit 16 continues to drive the object. Therefore, it is not necessary to install a door sensor to detect the opening of the second opening 302.

[0187] like Figure 14 As shown in (B), the recovery unit 320 includes walls 341, 342, 343, 344, and 345, which restrict access from the second opening 302 to the holding disc 20 or the tool drive unit 30. The walls 341, 342, 343, 344, and 345 form a box 340. The box 340 opens toward the second opening 302.

[0188] like Figure 15As shown, a grinding chip inlet 346 is formed in the wall 341, which serves as the top of the housing 340. The inlet 346 is connected to the outlet 233 or 243 of the housing 40 via pipes 250 or 260. The inlet 346 may also be connected to the outlet 233 or 243 via either pipes 250 or 260. The grinding chips pass through the inlet 346 of the housing 340 and fall into the interior of the housing 340.

[0189] The recycling section 320 may also include a pair of guide walls 351, 352 inside the bin 340, which guide the grinding chips falling from the inlet 346 of the bin 340.

[0190] like Figure 15 As shown, the recycling unit 320 includes multiple containers 331 and 332 for collecting grinding chips. Each of the multiple containers 331 and 332 can be removed from the interior of the housing 340. For example, grinding chips can be collected using one container 331 while another container 332 is removed and emptied. However, the number of containers can also be only one.

[0191] like Figure 14 As shown in (B), container 340 has doors 347 and 348 for opening and closing containers 331 and 332. Doors 347 and 348 are independent of the second door 312, but can also be used as the second door 312. An operator or robot opens doors 347 and 348 and removes containers 331 and 332 to the outside of container 340. Then, the operator or robot returns the empty containers 331 and 332 to the inside of container 340 and closes doors 347 and 348.

[0192] like Figure 15 As shown, the collection unit 320 includes a switching mechanism 360 for changing the destination of grinding chips. The switching mechanism 360, for example, has a rotating plate 361 and an operating lever 362. The rotating plate 361 is tilted in the path where the grinding chips fall. The operating lever 362 rotates the rotating plate 361, changing its tilt direction. By changing the tilt direction of the rotating plate 361, the destination of the grinding chips can be changed.

[0193] The rotation diameter of the rotating plate 361 is greater than the interval between the pair of guide walls 351 and 352. The pair of guide walls 351 and 352 are located within the rotation range of the rotating plate 361. The pair of guide walls 351 and 352 also function as stops to prevent the rotation of the rotating plate 361 from stopping. The rotation axis 363 of the rotating plate 361 is horizontally arranged and located directly below the horizontal center of the pair of guide walls 351 and 352.

[0194] like Figure 15As shown in (A), the rotating plate 361 tilts to the lower left while in contact with the guide wall 352 on the right, causing the grinding chips to fall into the container 331 on the left. In this case, the grinding chips are collected in the container 331 on the left.

[0195] On the other hand, such as Figure 15 As shown in (B), the rotating plate 361 tilts downward to the right while in contact with the guide wall 351 on the left, causing the grinding chips to fall into the container 332 on the right. In this case, the grinding chips are collected in the container 332 on the right.

[0196] The recycling unit 320 includes a locking mechanism 370. The locking mechanism 370 restricts the removal of the container 331, which serves as the destination for grinding chips, while allowing the removal of other containers 332. Alternatively, the locking mechanism 370 restricts the removal of the container 332, which serves as the destination for grinding chips, while allowing the removal of other containers 331. During the grinding chip collection process, it prevents the accidental removal of the container serving as the destination and prevents grinding chips from scattering inside the box 340.

[0197] As a locking mechanism 370, an operating lever 362 is used, for example, as part of a switching mechanism 360. The operating lever 362 extends linearly from the rotation axis 363 of the rotating plate 361 into the container's channel, restricting the removal of the container. For example, as... Figure 14 As shown in (B), the lever 362 restricts the removal of container 331 by pressing door 347. Additionally, the lever 362 restricts the removal of another container 332 by pressing another door 348. The lever 362 switches between a state where only door 347 is pressed and a state where only the other door 348 is pressed. If the lever 362 is a locking mechanism 370, the locking target can be switched simultaneously with the storage destination, preventing the locking target from being forgotten.

[0198] Containers 331 and 332 include mesh to trap grinding chips and separate liquid from them. Containers 331 and 332 are entirely mesh baskets, but may only have mesh on their lower walls. Furthermore, the recovery section 320 includes a mesh-like holding section 333 that supports containers 331 and 332 from below, allowing the liquid to drip downwards. A partition plate 334 may also be provided above the holding section 333 to separate adjacent containers 331 and 332. After dripping from containers 331 and 332, the liquid passes through the holding section 333 and is discharged to the outside of the recovery section 320. By trapping only grinding chips inside the recovery section 320, the frequency of removing containers 331 and 332 from the tank 340 can be reduced.

[0199] The grinding apparatus and grinding method of this disclosure have been described above, but this disclosure is not limited to the above-described embodiments. Various modifications, alterations, substitutions, additions, deletions, and combinations are possible within the scope of the claims. These, of course, also fall within the technical scope of this disclosure.

[0200] For example, the number of tool drive units 30 only needs to be one or more. Additionally, the number of retaining discs 20 only needs to be greater than the number of tool drive units 30. Furthermore, the interior of the housing 40 is divided into four chambers B0 to B3 by a fixed partition wall 45, but the number of these chambers is not limited to four; two or more are sufficient.

[0201] This application claims priority based on Japan Patent Application No. 2020-161265, filed with the Japan Patent Office on September 25, 2020, the entire contents of which are incorporated herein by reference.

[0202] Explanation of reference numerals in the attached figures

[0203] 1. Grinding device; 10. Table; 20. Holding plate; 30. Tool drive unit; 51. Nozzle; 60. Table cover; 61. Inclined part; W. Base plate.

Claims

1. A grinding apparatus, wherein, This grinding device has the following features: Multiple holding disks, which hold the substrate; A tool drive unit that drives a grinding tool pressed against the substrate; A platform, which holds a plurality of said holding disks about a rotation center line and rotates about said rotation center line; and The platform cover rotates together with the platform. The platform cover includes an inclined portion that tilts downwards the further away from the rotation center line. The grinding apparatus is equipped with a nozzle that supplies cleaning fluid to the inclined portion between the top of the inclined portion and the retaining plate when grinding the substrate.

2. The grinding apparatus according to claim 1, wherein, The nozzle supplies the cleaning fluid to the inclined section at a position that allows the cleaning fluid to reach the top of the inclined section.

3. The grinding apparatus according to claim 1 or 2, wherein, The nozzles have multiple supply ports spaced apart around the circumference of the platform.

4. The grinding apparatus according to claim 1 or 2, wherein, The nozzle's supply port is an arc-shaped slit or a straight slit along the circumference of the platform.

5. The grinding apparatus according to claim 1 or 2, wherein, The grinding apparatus includes a measuring device that measures the thickness of the substrate. The measuring device includes the nozzle.

6. The grinding apparatus according to claim 5, wherein, The measuring device includes a first height sensor for measuring the height of the substrate and a second height sensor for measuring the height of the holding plate.

7. The grinding apparatus according to claim 6, wherein, The measuring device includes a first arm for holding the first height sensor, a second arm for holding the second height sensor, and a bracket for holding the first arm and the second arm. The nozzle is located on the lower surface of the bracket.

8. The grinding apparatus according to claim 7, wherein, The grinding apparatus includes a fixed axis, which is positioned along the rotation center line of the table. The bracket of the measuring instrument is mounted on the upper surface of the fixed shaft and protrudes radially outward from the fixed shaft. The nozzle is located on the lower surface of the bracket, protruding radially outward toward the fixed axis.

9. The grinding apparatus according to claim 1 or 2, wherein, The grinding apparatus includes a fixed axis, which is positioned along the rotation center line of the table. The nozzle is mounted on the upper surface of the fixed shaft and protrudes radially outward from the fixed shaft.

10. The grinding apparatus according to claim 8, wherein, The inclined portion forms an opening at its top for the fixed shaft to pass through. The platform cover has a central cylindrical portion that rises from the opening edge of the opening portion of the inclined portion. The nozzle is positioned radially outward from the central cylinder.

11. The grinding apparatus according to claim 1 or 2, wherein, The grinding device includes a second nozzle that supplies cleaning fluid from above to the base of the inclined portion of the platform.

12. The grinding apparatus according to claim 11, wherein, The grinding apparatus includes: a housing that houses a plurality of the retaining discs; and a fixed partition wall that divides the interior of the housing into a plurality of chambers about the rotation center line of the stage. The plurality of chambers include a grinding chamber for grinding the substrate and a feeding and unloading chamber for feeding and unloading the substrate. The second nozzle is located near the boundary between the grinding chamber and the feed and discharge chambers.

13. The grinding apparatus according to claim 12, wherein, When viewed from above, if either the clockwise or counterclockwise direction is designated as the first direction, and the remaining direction as the second direction, then the interior of the housing is sequentially divided in the first direction into the feed-in / feed-out chamber, the first grinding chamber for performing the first grinding of the substrate, the second grinding chamber for performing the second grinding of the substrate after the first grinding, and the third grinding chamber for performing the third grinding of the substrate after the second grinding. The second nozzle is located near both the boundary between the primary grinding chamber and the feed / ejection chamber, and the boundary between the tertiary grinding chamber and the feed / ejection chamber. The grinding apparatus includes a control unit that performs the following control: when the table is rotated in the first direction, cleaning fluid is supplied from above to the base from the second nozzle disposed in the third grinding chamber; and when the table is rotated in the second direction, cleaning fluid is supplied from above to the base from the second nozzle disposed in the first grinding chamber.

14. The grinding apparatus according to claim 1 or 2, wherein, The nozzle does not supply the cleaning fluid to the holding plate and the substrate held on the holding plate.

15. A grinding method for grinding a substrate using a grinding apparatus, the grinding apparatus comprising: a plurality of holding discs holding the substrate; a stage holding the plurality of holding discs about a rotation center line and rotating about the rotation center line; and a stage cover rotating together with the stage, the stage cover including an inclined portion that tilts downwards the further away from the rotation center line, wherein... The grinding method includes the following steps: when grinding the substrate, a cleaning fluid is supplied to the inclined portion between the top of the inclined portion and the retaining disk.

16. The grinding method according to claim 15, wherein, During the grinding of the substrate, the cleaning fluid is not supplied to the holding disk and the substrate held in the holding disk.

Images