TW201934254A - Grinding apparatus comprises two cleansing nozzles to respectively spray cleansing water to an outer circumferential edge of a wafer during rough grinding and fine grinding respectively - Google Patents

Abstract

The object of the present invention prevents occurrence of chipping at an outer circumferential edge of a wafer. The solution of the present invention is a grinding apparatus 1 comprising cleansing nozzles 50A, 50B that spray cleansing water 53 to an outer circumferential edge Wc of a wafer W that is retained on a retaining platform 10 rotated by a rotating means 13, such that during rough grinding of wafer Q, the cleansing nozzle 50A sprays cleansing water 53 to the outer circumferential edge Wc of the wafer W to wash out chips 100 attached to the outer circumferential edge Wc, and during fine grinding of wafer W, the cleansing nozzle 50B sprays cleansing water 53 to the outer circumferential edge Wc of the wafer W that has been subjected to rough grinding for cleansing. Therefore, when applying fine grinding to thin the wafer W to a wafer thickness that is smaller than the chips 100, there would be no concern about the chips 100 that are attached to the outer circumferential edge Wc dragged onto the upper surface of the wafer Q. Thus, there would be no chipping at the outer circumferential edge Wc of the wafer W that has been thinned.

Description

Grinding device

The invention relates to a grinding device for grinding and processing a wafer.

A grinding device for grinding a wafer can grind the wafer to a predetermined thickness, and includes: a holding table for holding the wafer; and a grinding method, a grinding wheel is rotatably mounted, and the grinding stone is fixed on the grinding wheel and held against the grinding wheel. The wafer on the holding table is ground. In the grinding device, after exchanging the grinding wheel or the holding table, etc., in order to make the holding surface of the holding table parallel to the grinding surface of the grinding stone, self-grind grinding the holding surface with the grinding stone (for example, Refer to Patent Document 1) below.

The holding table is composed of a disc-shaped perforated plate and a frame surrounding the perforated plate, and the upper surface of the perforated plate and the top surface of the frame are made the same surface by self-grinding. The upper surface of the perforated plate becomes a holding surface for holding a wafer. On the one hand, the upper surface of the housing is brought into contact with the contact-type height measuring portion to be a measuring surface for measuring the height of the holding surface. In the grinding process, the height of the upper surface of the wafer held by the holding surface is measured, and the height of the upper surface of the frame is measured. The thickness of the wafer is calculated from the height difference, and the wafer is ground to the desired thickness. The grinding process includes rough grinding of the rough ground wafer and fine grinding of the rough ground wafer to a desired finished thickness, so that the thinned wafer is thinned to a thickness of, for example, 5 to 10 μm. Chipping occurs on the outer periphery of the finely ground wafer. Since the abrasive grains of the grinding grindstone used for fine grinding cause chipping, as a countermeasure, the grinding grain for fine grinding is constituted by small abrasive grains to prevent chipping of the outer periphery of the wafer.
[Xizhi technical literature]
[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2014-237210

[Problems to be Solved by the Invention]
However, even if the countermeasures mentioned above can be proposed to reduce chipping at the outer periphery of the wafer, it is still difficult to prevent chipping at all.

The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to prevent chipping at the outer periphery of a wafer.

[Technical means to solve the problem]
The present invention is a grinding apparatus including a holding table for holding a wafer in a disc shape, a rotating means for rotating the holding table, and a grinding wheel in which a grinding stone is arranged in a ring shape and rotated by the grinding stone. Grinding means for grinding the wafer held by the holding table; the grinding device has a cleaning nozzle, and sprays cleaning water on an outer peripheral edge of the wafer held by the holding table by rotating the rotating means.

Preferably, the cleaning nozzle includes a cleaning port, sprays the cleaning water on an outer peripheral edge of the wafer held by the holding table, and positions the cleaning nozzle in a direction from the outer peripheral side of the wafer held by the holding table to the holding surface. The outer peripheral edge of the upper wafer is further inside the tangential direction, and the ejection port is directed downward at a predetermined angle with respect to the holding surface, and the cleaning water is sprayed on the outer peripheral edge of the wafer.

In addition, the present invention is preferably provided with a pressing nozzle, spraying the cleaning water on the upper side of the outer peripheral portion of the wafer spraying the cleaning water from the cleaning nozzle, and pressing the wafer against the holding surface.

[Inventive effect]
The grinding device of the present invention is provided with a cleaning nozzle, and sprays cleaning water on the outer periphery of the wafer held by the holding table rotated by the rotating means. For example, when rough grinding a wafer, the cleaning nozzle can be sprayed on the outer periphery of the wafer. The cleaning water is used to wash away the grinding chips or abrasive particles attached to the outer periphery. In addition, when the wafer is finely ground, the washing nozzle can also be sprayed with the washing water on the outer periphery of the rough ground wafer to clean the wafer, without the grinding chips. Or the abrasive grains are attached to the outer periphery of the wafer, so there is no doubt that grinding chips or abrasive grains will be pulled to the upper surface of the wafer W during the fine grinding. Therefore, chipping of the outer periphery of the thinned wafer according to the present invention no longer occurs.

The cleaning nozzle is configured with a cleaning port, and sprays the cleaning water on an outer peripheral edge of the wafer held by the holding table; and the cleaning nozzle is positioned from the outer peripheral side of the wafer held by the holding table to the wafer in the holding surface direction. The tangential direction of the outer peripheral edge is further inward than the holding surface at a predetermined angle, and the cleaning water is sprayed on the outer peripheral edge of the wafer. Therefore, the cleaning effect of the outer peripheral edge of the wafer during grinding can be improved. The outer periphery of the thinned wafer will not be chipped.

In addition, the present invention includes a pressing nozzle that sprays cleaning water from an upper side of an outer peripheral portion of a wafer on which the cleaning water is sprayed from the cleaning nozzle and presses the wafer against a holding surface. Therefore, even if the predetermined angle of the cleaning nozzle is set to be relative Because the holding surface is close to a parallel angle, the outer peripheral edge of the wafer does not float from the holding table during cutting, and the outer peripheral edge can be cleaned well.

The grinding apparatus 1 shown in FIG. 1 is an example of a grinding apparatus for grinding a wafer W as a workpiece. The grinding device 1 includes a device base 2 extending in the Y-axis direction, and stands 3a and 3b are arranged adjacent to the -Y direction side of the device base 2. A cassette 4a for storing the wafer W before grinding is placed on the base 3a, and a cassette 4b for storing the wafer W after grinding is placed on the base 3b. A loading / unloading means 5 is disposed at a position facing the cassette 4a and the cassette 4b, and the wafer W is unloaded from the cassette 4a and the wafer W is loaded into the cassette 4b. Disposed in the movable range of the carry-in and carry-out means 5 are: a temporary means 6 for temporarily holding the wafer W; and a cleaning means 7 for cleaning the grinding chips attached to the wafer W after the grinding.

The grinding device 1 is provided with a rotatable rotary table 8; a holding table 10 having a holding surface 11a for holding a wafer W arranged on the rotary table 8; a rotation means 13 for rotating the holding table 10; a grinding means 20A; The wafer W held by the holding table 10 is subjected to rough grinding; and the grinding means 20B is used to perform grinding on the wafer W after the rough grinding is held by the holding table 10. A first transfer means 9 a is provided near the temporary means 6, and transfers the wafer W temporarily before the grinding to the temporary means 6 to the holding table 10. In addition, a second transfer means 9 b is provided near the cleaning means 7, and the ground wafer W held by the holding table 10 is transferred to the cleaning means 7.

The holding tables 10 are arranged at an angle with the center of the rotary table 8 as the center, for example, three holding tables are arranged. The holding table 10 is composed of a disc-shaped porous plate 11 and a frame 12 that houses the porous plate 11. The upper surface of the porous plate 11 is a holding surface 11 a that attracts and holds the wafer W. The ring-shaped outer peripheral side upper surface of the frame 12 surrounding the holding surface 11a of the holding table 10 is a reference surface 12a having the same height as the holding surface 11a. Rotating means 13 are respectively connected to the lower ends of the holding tables 10 so as to be able to rotate at a predetermined rotation speed. By rotating the rotary table 8, the holding table 10 can be rotated. In addition, the holding surface 11a of the holding table 10 is formed with its central portion as an apex, and the outer peripheral direction is inclined downward to form an inclined surface.

A post 14 a extending in the Z-axis direction is erected at an end portion on the + Y direction side of the device base 2. A grinding means 20A is disposed on the front side of the column 14a through a grinding feed means 30A. The grinding means 20A includes: a main shaft 21 having an axis in the Z-axis direction; a motor 22 connected to one end of the main shaft 21; a main shaft housing 23 to rotatably support the main shaft 21; a bracket 24 holding the main shaft housing 23; and a grinding wheel 26 The lower end of the main shaft 21 is detachably mounted through a mounting member 25; and a grinding grindstone 27a for rough grinding is arranged annularly at the lower portion of the grinding wheel 26. As the particle size of the abrasive grain of the grinding stone 27a, for example, # 600 (average particle size: 20 µm) is used. In addition, when the motor 22 is driven and the main shaft 21 is rotated, the grinding wheel 26 can be rotated at a predetermined rotation speed.

The grinding feed means 30A includes a ball screw 31 extending in the Z-axis direction, a motor 32 connected to one end of the ball screw 31, a pair of guide rails 33 extending in parallel with the ball screw 31 and disposed on the column 14a, and a lifting plate 34, One side surface is connected to the bracket 24. The guide rail 33 is slidably engaged with the other surface of the lifting plate 34, and the ball screw 31 is screwed with a nut formed at a central portion of the lifting plate 34. When the ball screw 31 is driven by the motor 32, the lifting plate 34 and the grinding means 20A can be raised and lowered simultaneously in the ± Z direction.

A column 14b is erected at a predetermined interval between the end portion on the + Y direction side of the device base 2 and the column 14a. A grinding means 20B is disposed on the front side of the column 14b through a grinding feed means 30B. The grinding means 20B includes a grinding wheel 26, which is detachably mounted on the lower end of the main shaft 21 through a mounting member 25, and a grinding grindstone 27b for fine grinding, which is arranged annularly below the grinding wheel 26; The structure is the same as that of the grinding means 20A. As the particle size of the abrasive grain of the grinding stone 27b, # 8000 is used, for example. The grinding means 20B drives the motor 22 and rotates the main shaft 21, whereby the grinding wheel 26 can be rotated at a predetermined rotation speed.

The grinding feed means 30B has the same structure as the grinding feed means 30A. That is, the grinding feed means 30B includes: a ball screw 31; a motor 32 connected to one end of the ball screw 31; a pair of guide rails 33 extending in parallel with the ball screw 31 and arranged on the column 14b; and a lifting plate 34 on one side The surface is connected to the bracket 24; the ball screw 31 is driven by the motor 32, so that the lifting plate 34 and the grinding means 20B can be raised and lowered in the ± Z direction at the same time.

A pillar 15 is erected in the center of the turntable 8. A case 16 is fixed to an upper end surface of the pillar 15. A thickness measuring means 40A is provided on a side surface of the grinding means 20A side (-X direction side) of the case 16, and measures the thickness of the wafer W roughly ground by the grinding means 20A, and the grinding means 20B of the case 16 A thickness measuring means 40B is disposed on the side surface (+ X direction side), and measures the thickness of the wafer W finely ground by the grinding means 20B. The thickness measuring means 40A and 40B are contact-type height gauges, which include a first gauge 41 that measures the height of the upper surface of the wafer W held on the holding surface 11a of the holding table 10, and a second gauge 42 that measures The holding surface height of the holding surface 11 a of the holding table 10.

The first gauge 41 has a measuring head that contacts the front surface of the object to be measured, and the position of the measuring head corresponds to the position of the holding surface 11 a of the holding table 10. In the first gauge 41, the height when the measuring head contacts the upper surface of the wafer W held by the holding table 10 can be measured as the upper surface height of the wafer W. The second gauge 42 has a measuring head that contacts the front surface of the object to be measured, and corresponds to the position of the reference surface 12 a of the holding table 10. In the second gauge 42, the height when the measuring head contacts the reference surface 12 a can be measured as the holding surface height of the holding table 10. The thickness measuring means 40A and 40B can calculate the difference between the measured value of the first gauge 41 and the measured value of the second gauge 42 as the thickness of the wafer W.

The grinding apparatus 1 includes cleaning nozzles 50A and 50B, and sprays cleaning water toward the outer peripheral edge Wc of the wafer W held by the holding table 10 rotated by the rotating means 13. The cleaning nozzle 50A is supported by a support portion 17 a provided on the outside of the turntable 8 on the grinding means 20A side (-X direction side). The cleaning nozzle 50A includes a spraying port 51 that sprays cleaning water on the outer periphery Wc of the wafer W held by the holding table 10, and the spraying port 51 is connected to a cleaning water supply source 52. The cleaning nozzle 50A can clean the outer periphery Wc of the wafer W during rough grinding of the wafer W by the grinding means 20A. The cleaning nozzle 50B is supported by a support portion 17 b provided on the outside of the turntable 8 on the grinding means 20B side (+ X direction side). The configuration of the cleaning nozzle 50B is the same as that of the cleaning nozzle 50A, and the spray port 51 is connected to a cleaning water supply source 52. The cleaning nozzle 50B can clean the outer peripheral edge Wc of the wafer W during the fine grinding of the wafer W by the grinding means 20B.

Next, an operation example of the grinding device 1 shown in FIG. 1 will be described. The wafer W before grinding is adhered with the adhesive film T on the lower surface opposite to the upper surface (the surface to be ground) and is accommodated in the cassette 4 a in a plurality of pieces. The carrying-in means 5 takes out one wafer W before grinding from the cassette 4 a, and temporarily holds the wafer W in the temporary means 6. After the wafer W is aligned by the temporary means 6, the wafer W is transferred from the temporary means 6 to the holding table 10 by the first transfer means 9a. The holding table 10 sucks and holds the wafer W through the adhesive film T by the holding surface 11 a that acts as a suction force of the suction source.

When the rotary table 8 is rotated, the holding table 10 holding the wafer W is moved below the grinding means 20A. By the rotation means 13, as shown in FIG. 2, the holding table 10 is rotated in the direction of arrow A, for example. Next, the grinding feed means 30A shown in FIG. 1 lowers the grinding means 20A in the -Z direction, and the grinding means 20A rotates the main shaft 21 to rotate the grinding grindstone 27a in, for example, the direction of the arrow A to perform grinding grinding. The stone 27a performs rough grinding while pressing the upper surface of the wafer W.

During rough grinding, cleaning water 53 is sprayed from the cleaning nozzle 50A toward the outer peripheral edge Wc of the wafer W to perform cleaning. Here, as shown in FIG. 2, in the rotation locus of the grinding grindstone 27 a rotating in the direction of the arrow A, the arc-shaped area where the grinding grindstone 27 a actually contacts the upper surface of the wafer W and grinds becomes the grind area P. In the rough grinding, the grinding stone 27 a continues to pass through the center Wo of the wafer W, and the grinding surface of the grinding stone 27 a contacts the upper surface of the wafer W in the grinding region P to perform rough grinding.

When cleaning the outer peripheral edge Wc of the wafer W during rough grinding, it is preferable to position the cleaning nozzle 50A from the outer peripheral side of the wafer W held by the holding table 10 to the outer peripheral edge Wc of the wafer W in the holding surface direction. The tangential direction is further inside, and the spray port 51 is directed downward at a predetermined angle with respect to the holding surface 11a of the holding table 10 shown in FIG. 3, and the cleaning water 53 is sprayed on the outer peripheral edge Wc of the wafer W. The cleaning nozzle 50A shown in this embodiment is positioned at a spray position SP1 slightly inward from the tangential direction of the outer peripheral edge Wc of the wafer W shown in FIG. 2, and from the spray port 51 facing the crystal rotating in the direction of arrow A. The rotation direction of the circle W is such that the washing water 53 is sprayed toward the outer periphery Wc.

The position of the cleaning nozzle 50A is not limited to the above-mentioned spraying position SP1. For example, the cleaning nozzle 50A may be positioned at the spraying position SP2 of the jettable cleaning water 53 along the tangential direction of the outer periphery Wc of the wafer W, or the cleaning nozzle 50A may be positioned opposite to the spraying positions SP1 and SP2. The side position is toward the outer peripheral edge Wc of the wafer W, and the spray position SP3 at which the cleaning water 53 can be sprayed.

As shown in FIG. 3, as a predetermined angle at which the cleaning water 53 is sprayed from the spray port 51 of the cleaning nozzle 50A, for example, it is set to face downward at 45 ° with respect to the holding surface 11 a of the holding table 10. While the cleaning water 53 is sprayed from the spray port 51 of the cleaning nozzle 50A positioned as described above to the outer peripheral edge Wc of the wafer W, rough grinding is performed to wash away the chips 100 attached to the outer peripheral edge Wc of the wafer W. The chips 100 include grinding chips or abrasive particles. Although the predetermined angle of the cleaning nozzle 50A is not particularly limited, when the angle is smaller than 45 °, the wafer W will float from the holding table 10 by the cleaning water 53 sprayed from the spray port 51, and when the angle is larger than 45 ° , The grinding chips or abrasive particles cannot be completely removed from the outer periphery Wc of the wafer W, and the cleaning effect becomes poor. Therefore, the predetermined angle of the cleaning nozzle 50A is preferably 45 °, and the cleaning effect of the outer peripheral edge Wc of the wafer W can be improved.

In the rough grinding, the thickness measurement means 40A shown in FIG. 1 is used to continuously monitor the change in the thickness of the wafer W, and the rough grinding is finished when the wafer W has a desired thickness. The thickness of the wafer W after rough grinding is set to 100 to 200 μm. In addition, the chip 100 generated during rough grinding is 10 to 20 µm. Thereafter, the rotary table 8 is further rotated to move the holding table 10 holding the wafer W after the rough grinding to a position below the grinding means 20B. The holding table 10 is rotated, while the grinding means 20B rotates the main shaft 21 and the grinding grindstone 27b rotates at a predetermined rotation speed. The grinding feed means 30B lowers the grinding means 20B in, for example, the -Z direction. The grinding stone 27b grinds the upper surface of the wafer W to a desired completed thickness. Even when the fine grinding is performed by the grinding means 20B, as in the grinding means 20A, the grinding grindstone 27b contacts the upper surface of the wafer W in the grinding area P shown in FIG. 2 to perform fine grinding. The desired finished thickness is set to, for example, 5 to 10 μm.

Even when the outer periphery Wc of the wafer W is cleaned during fine grinding, the cleaning nozzle 50B is positioned at the spray position SP1 shown in FIG. 2 and is 45 to the holding surface 11a of the holding table 10 shown in FIG. 3, for example. With the spray port 51 facing downward, spray the cleaning water 53 on the outer peripheral edge Wc of the wafer W. While spraying the cleaning water 53 from the spray port 51 of the cleaning nozzle 50B positioned as described above to the outer peripheral edge Wc of the wafer W, the outer peripheral edge Wc of the wafer W is cleaned by fine grinding. During fine grinding, a large amount of chips 100 are removed from the outer peripheral edge Wc, and even if the chips 100 generated after the rough grinding of the outer peripheral edge Wc are temporarily left, they can be washed away with the washing water 53. In the fine grinding, the thickness measurement means 40B shown in FIG. 1 is used to continuously monitor the change in the thickness of the wafer W, and the fine grinding is finished when the wafer W has a desired finished thickness. In addition, the cleaning nozzle 50B may be positioned at the spray position SP2 or the spray position SP3.

As described above, since the grinding device 1 of the present invention includes the cleaning nozzles 50A and 50B spraying the cleaning water 53 on the outer periphery Wc of the wafer W held by the holding table 10 rotated by the rotation means 13, the grinding means 20A performs rough grinding of the crystal. In the circle W, the cleaning nozzle 50A sprays the cleaning water 53 on the outer peripheral edge Wc of the wafer W, and the chips 100 adhering to the outer peripheral portion Wc can be washed away. In addition, when the wafer W is finely ground by the grinding method 20B, the outer peripheral edge Wc of the rough ground wafer W can be sprayed with the cleaning water 53 by the cleaning nozzle 50B. Therefore, for example, the wafer W is thinned by fine grinding. When the wafer thickness is made smaller than the chip 100, there is no doubt that the chip 100 adhering to the outer peripheral edge Wc is pulled to the upper surface of the wafer W. Therefore, chipping of the outer periphery Wc of the thinned wafer W according to the present invention no longer occurs.

The grinding apparatus 1 may include, for example, as shown in FIG. 4, a pressing nozzle 60 that sprays cleaning water 62 from the cleaning nozzle 50A (50B) above the outer peripheral portion of the wafer W and sprays the cleaning water 62 and presses the wafer on the holding surface 11 a. W. The pressing nozzle 60 is provided with an ejection port 61 that ejects the washing water 62 and is positioned directly above the outer peripheral edge Wc portion of the wafer W. In the example of FIG. 4, as a predetermined angle at which the washing water 53 is sprayed from the spray port 51 of the washing nozzle 50A (50B), for example, it is set to face downward by 25 ° with respect to the holding surface 11 a of the holding table 10. While spraying the cleaning water 53 from the spray port 51 of the cleaning nozzle 50A (50B) positioned as described above to the outer periphery Wc of the wafer W, the spray is sprayed from the spray port 61 that presses the nozzle 60 toward the outer peripheral portion while cleaning The cleaning water 62 presses the outer peripheral edge Wc on the holding surface 11a, and the chips 100 attached to the outer peripheral edge Wc of the wafer W are washed away to perform rough grinding and fine grinding of the wafer W.

As described above, in the case where the grinding apparatus 1 includes the pressing nozzle 60, the cleaning water 62 can be sprayed from the pressing nozzle 60 to press the wafer W downward, and even if the predetermined angle of the cleaning nozzle 50A (50B) is set to an angle smaller than 45 ° During the grinding, the outer periphery Wc of the wafer W does not float from the holding table, and the outer periphery Wc can be cleaned well.

The present invention is also applicable to a case where the chamfered portion of the outer peripheral edge Wc of the wafer W is ground and removed before the rough grinding and fine grinding of the wafer W (trimming). That is, when the outer peripheral edge Wc of the wafer W is trimmed, the outer peripheral edge Wc of the wafer W may be sprayed with cleaning water by a cleaning nozzle.

Although the grinding device 1 shown in the above-mentioned embodiment is a two-axis device provided with two grinding means 20A and 20B, it is not limited to this device configuration, and the present invention is also applicable to a single-axis device provided with one grinding means. .

1‧‧‧Grinding device

2‧‧‧ device base

3a, 3b ‧‧‧ pedestal

4a, 4b‧‧‧ Cassette

5‧‧‧ Means of moving out

6‧‧‧ temporary table

7‧‧‧ cleaning methods

8‧‧‧ Turntable

9a‧‧‧The first transfer means

9b‧‧‧ 2nd transfer method

10‧‧‧ holding table

11‧‧‧ multi-well plate

12‧‧‧Frame

13‧‧‧ Rotation means

14a, 14b‧‧‧pillars

15‧‧‧ pillar

16‧‧‧shell

17a, 17b‧‧‧ support

20A, 20B ‧ ‧ grinding methods

21‧‧‧ Spindle

22‧‧‧ Motor

23‧‧‧ Spindle housing

24‧‧‧ Bracket

25‧‧‧Mounting parts

26‧‧‧grinding wheel

27a, 27b ‧ ‧ grinding grinding stone

30A, 30B ‧‧‧ Grinding feed means

31‧‧‧ball screw

32‧‧‧ Motor

33‧‧‧Guide

34‧‧‧ Lifting plate

40A, 40B‧‧‧‧Thickness measuring means

41‧‧‧The first gauge

42‧‧‧ 2nd gauge

50A 、 50B‧‧‧Cleaning nozzle

51‧‧‧jet port

52‧‧‧ source of washing water

53‧‧‧washing water

60‧‧‧Press the nozzle

61‧‧‧jet port

62‧‧‧washing water

FIG. 1 is a perspective view showing the structure of the grinding device.

FIG. 2 is an explanatory view showing a grinding area of a grinding stone and also explaining a position of a cleaning nozzle.

3 is a cross-sectional view showing a state where a wafer is sprayed with cleaning water from a cleaning nozzle on the outer periphery of the wafer and the wafer is ground with a grinding stone.

FIG. 4 shows a state in which the wafer is grinded with a grinding stone while spraying the cleaning water from the cleaning nozzle on the outer periphery of the wafer and spraying the cleaning water from the upper side of the outer peripheral portion of the wafer with the pressing nozzle while pressing. Sectional view.

Claims (3)

A grinding device includes a holding table for holding a wafer in a disc shape, a rotating means for rotating the holding table, and a grinding wheel in which a grinding grindstone is arranged annularly, and the holding is grinded by the grinding grindstone. The wafer grinding method maintained by the platform; The grinding apparatus includes a cleaning nozzle, and sprays cleaning water on an outer peripheral edge of a wafer held by the holding table while being rotated by the rotating means. The grinding device according to item 1 of the scope of patent application, wherein the cleaning nozzle is provided with a cleaning port, and the cleaning water is sprayed on the outer peripheral edge of the wafer held by the holding table; The cleaning nozzle is positioned further in the tangential direction from the outer peripheral side of the wafer held by the holding table to the outer peripheral edge of the wafer in the holding surface direction, and the ejection port faces downward at a predetermined angle with respect to the holding surface. And spray the cleaning water on the outer periphery of the wafer. The grinding device according to item 2 of the scope of patent application, further comprising a pressing nozzle that sprays cleaning water on an upper side of an outer peripheral portion of the wafer spraying the cleaning water from the cleaning nozzle, and presses the wafer against the holding surface.