Cleaning apparatus and wafer manufacturing method

Abstract

To shorten a cleaning time in a washing device that sprays two fluids, which are a mixture of water and air.SOLUTION: A washing device 10 that sprays two fluids F, which are a mixture of water and air, from a two-fluid nozzle 14 placed above an object to be cleaned (for example, a wafer W or a porous plate 32) to clean the upper surface of the object to be cleaned includes a plate 11 arranged above the top surface of the object to be cleaned with a gap G, and an opening 111 that is formed in the plate 11 and allows the two fluids F sprayed from the two-fluid nozzle 14 to pass through the area without being obstructed and sprayed onto the object to be cleaned. The two fluids F that passed through the opening 111 are sprayed onto the top surface of the object to be cleaned, and then the water flows radially through a gap G between the upper surface of the object to be cleaned and the lower surface of the plate 11 in a direction away from the opening 111, thereby cleaning the object to be cleaned.SELECTED DRAWING: Figure 3

Description

TECHNICAL FIELD

[0001] The present invention relates to a cleaning apparatus that cleans the upper surface of an object to be cleaned by ejecting a two-fluid mixture of water and air from a two-fluid nozzle.

BACKGROUND ART

[0002] Conventionally, the upper surface of a wafer held on a chuck table is cleaned by ejecting a two-fluid mixture of water and air from a two-fluid nozzle toward the upper surface of the wafer.

[0003] The two-fluid mixture ejected from the two-fluid nozzle may reflect off the upper surface of the wafer and scatter inside the processing apparatus. To prevent such scattering, a cleaning apparatus has been proposed that includes a box surrounding the two-fluid nozzle, which confines the scattered two-fluid mixture inside the box and separates the two-fluid mixture into gas and liquid (for example, see Patent Documents 1 and 2).

PRIOR ART DOCUMENTS

PATENT DOCUMENTS

[0004]

PATENT DOCUMENT 1

PATENT DOCUMENT 2

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0005] When a box surrounding the two-fluid nozzle is used as described above, a water layer is formed on the upper surface of the wafer enclosed by the box. As a result, the momentum of the two-fluid mixture ejected from the two-fluid nozzle is impeded by the water layer, and the cleaning area becomes smaller. This leads to the problem of extended cleaning time. This problem is not limited to cases where the object to be cleaned is a wafer, and similarly occurs in cases where the object to be cleaned is another workpiece or the chuck table itself that suction-holds the workpiece.

[0006] The objective of the present invention is to shorten the cleaning time in a cleaning device that sprays two fluids, a mixture of water and air. [Means for solving the problem]

[0007] In one embodiment, the cleaning device cleans the upper surface of an object to be cleaned by spraying a mixture of water and air from a two-fluid nozzle positioned above the object to be cleaned, the device comprising a plate positioned above the upper surface of the object to be cleaned with a gap between them, and an opening formed in the plate that allows the two fluids sprayed from the two-fluid nozzle to pass through without obstructing the area and be sprayed onto the object to be cleaned, wherein the two fluids that pass through the opening are sprayed onto the upper surface of the object to be cleaned, and then flow radially away from the opening through the gap between the upper surface of the object to be cleaned and the lower surface of the plate, cleaning the object to be cleaned. [Effects of the Invention]

[0008] According to the above embodiment, in a cleaning device that sprays two fluids, a mixture of water and air, the cleaning time can be shortened. [Brief explanation of the drawing]

[0009] [Figure 1] This is a perspective view showing a cleaning device, etc., according to one embodiment. [Figure 2] This is a plan view illustrating the flow of two fluids from an opening in a plate in one embodiment. [Figure 3] This is a front view illustrating the injection of two fluids by three two-fluid nozzles in one embodiment. [Figure 4] This is a plan view illustrating the flow of two fluids injected by three two-fluid nozzles in one embodiment. [Figure 5] This is a schematic front view showing the internal structure of a cleaning device in one embodiment (when the object to be cleaned is a chuck table). [Figure 6] This is a schematic front view showing the internal structure of a cleaning apparatus in one embodiment (when the object to be cleaned is the upper surface of a wafer). [Modes for carrying out the invention]

[0010] A cleaning apparatus according to one embodiment of the present invention will be described below with reference to the attached drawings.

[0011] Figure 1 is a perspective view showing a cleaning device 10, etc., according to one embodiment.

[0012] Note that the X-axis, Y-axis, and Z-axis directions shown in Figure 1 and Figures 2 to 6 (described later) are perpendicular to each other. The X-axis and Y-axis directions are horizontal, while the Z-axis direction is vertical. In each figure, of the two arrows indicating the X-axis direction, the side marked with +X is forward, and the side marked with -X is backward. Of the two arrows indicating the Y-axis direction, the +Y side is left, and the side marked with -Y is right. Of the two arrows indicating the Z-axis direction, the side marked with +Z is upward, and the side marked with -Z is downward.

[0013] As shown in Figure 1, the cleaning device 10 is integrally arranged with a base unit 20, a chuck table 30, a grinding mechanism 40, and a grinding lifting mechanism 50. The cleaning device 10 cleans the objects to be cleaned, such as the chuck table 30 itself (see Figure 5) and the wafer W (see Figure 6) held by the chuck table 30. Furthermore, the cleaning device 10 can clean not only wafer W that has been ground by the grinding mechanism 40, but also any workpiece (object to be cleaned), such as ceramic substrates and package substrates.

[0014] Furthermore, the cleaning device 10 can be considered a cleaning device or a cleaning system even if it integrates at least one of the base unit 20, the chuck table 30, and the grinding mechanism 40. Also, a device comprising at least the cleaning device 10 and the grinding mechanism 40 can be considered a grinding device or a grinding system. Moreover, if the grinding mechanism 40 is considered an example of a processing mechanism, a device comprising at least the cleaning device 10 and the processing mechanism can be considered a processing device.

[0015] The cleaning apparatus 10 includes a plate 11, a box 12, a two-fluid nozzle 14, an elevating unit 15, a horizontal moving unit 16, and an air source 17, a water source 18, and a control unit 19 shown in FIG. 5 which will be described later.

[0016] The plate 11 has, for example, a rectangular or circular plate shape, and is horizontally disposed parallel to the upper surface (surface to be cleaned) of the object to be cleaned so as to extend in the X-axis direction and the Y-axis direction. The plate 11 is formed with openings 111 shown in FIGS. 2 to 4 so as to penetrate in the vertical direction.

[0017] For example, one opening 111 is formed directly below one two-fluid nozzle 14. The opening 111 is preferably formed in a shape larger than the region of the jetted two-fluid F so as to allow the region of the two-fluid F jetted from the two-fluid nozzle 14 to pass therethrough without obstruction. The shape of the opening 111 may be appropriately set according to the shape of the ejection port of the two-fluid nozzle 14, etc., and is preferably circular if the shape of the ejection port of the two-fluid nozzle 14 is circular, and rectangular if the shape of the ejection port is rectangular. The number of the two-fluid nozzles 14 is arbitrary, but when only one two-fluid nozzle 14 is disposed, only one opening 111 is provided, and when three two-fluid nozzles 14 are disposed as shown in FIGS. 3 and 4, three openings 111 are preferably provided.

[0018] Further, the opening 111 is formed in a size that does not obstruct the region of the two-fluid F that is jetted from the ejection port in a divergent conical or pyramidal shape onto the surface to be cleaned.

[0019] The box 12 has four side plates 121 surrounding the two-fluid nozzle 14, and a top plate 122 connected to the upper ends of these side plates 121. The four side plates 121 are, for example, a front plate fixed to the upper part of the front end of the plate 11, a left side plate fixed to the upper part of the left end of the plate 11, a right side plate fixed to the upper part of the right end of the plate 11, and a back plate fixed to the upper part of the rear end of the plate 11, for a total of four arranged.

[0020] Since the space inside the box 12 is enclosed by the plate 11 and the box 12 (four side plates 121 and a top plate 122), the pressure in the space inside the box 12 increases as the two-fluid F is jetted by a two-fluid nozzle 14 described later. Therefore, an exhaust port 123 indicated by a broken line (hidden line) in FIG. 1 is formed in the side plate 121 which is a back plate. This exhaust port 123 may be formed in the top plate 122 or another side plate 121. Further, when the box 12 itself (or at least one of the side plates 121 and the top plate 122) is omitted, the exhaust port 123 is accordingly omitted.

[0021] The two-fluid nozzle 14 jets the two-fluid F shown in FIG. 3, which is a mixture of water and air, for example, vertically downward. The two-fluid nozzle 14 is preferably fixed to the box 12 or the plate 11 directly or indirectly inside the box 12. As a result, the plate 11, the box 12, and the two-fluid nozzle 14 are integrally moved up and down and horizontally by the driving of an elevating unit 15 and a horizontal moving unit 16 described later. The air (high-pressure air) mixed into the two-fluid F is supplied as air from an air source 17 shown in FIG. 5, and the water mixed into the two-fluid F is supplied from a water source 18 shown in FIG. 5. The water may be a liquid such as a cleaning liquid to which an additive is added.

[0022] Further, when the two-fluid nozzle 14 is indirectly arranged on the box 12 or the plate 11, a nozzle elevating mechanism for moving the two-fluid nozzle 14 toward and away from the surface to be cleaned may be provided to adjust the distance from the surface to be cleaned.

[0023] As described above, since an opening 111 is formed in the plate 11, the two fluids F ejected by the two-fluid nozzle 14 pass through the opening 111 and are sprayed onto the holding surface 321 of the porous plate 32 (chuck table 30) shown in Figure 5 or the upper surface Wa of the wafer W shown in Figure 6, which are examples of objects to be cleaned. The sprayed two fluids F then flow radially away from the opening 111 in the gap G between the upper surface of the object to be cleaned and the lower surface of the plate 11, as shown in Figures 2 and 4. This cleans the object to be cleaned. When multiple openings 111 are formed as shown in Figure 4, the two fluids F ejected from adjacent openings 111 may interfere with each other, but the two fluids F generally flow radially. Note that the two fluids F only need to flow radially at least immediately after being ejected toward the object to be cleaned through the opening 111. Also, although the plate 11 is shown as a circle with a dashed line (dandination line) in Figure 2, the plate 11 can be, for example, a rectangular plate as shown in Figure 4. However, the shape of plate 11 is arbitrary.

[0024] The lifting mechanism 15 shown in Figure 1 is an air cylinder, which is an example of a lifting mechanism (actuator). Two rods 151 protrude downward from the lower part of the lifting mechanism 15. The rods 151 are connected to the box 12. Therefore, when the two rods 151 move up and down by the drive of the air cylinder, the box 12 and the plate 11 and two-fluid nozzle 14 fixed to the box 12 move up and down. Note that the configuration of the lifting mechanism 15 is arbitrary and is not limited to an air cylinder; it can be anything that moves the plate 11 up and down.

[0025] The horizontal movement section 16 includes a motor 161, a ball screw 162, a slider 163, and a pair of upper and lower guide rails 164.

[0026] The motor 161 is positioned at the right end of the ball screw 162 and rotates the ball screw 162. The ball screw 162 is positioned in the Y-axis direction, and as the ball screw 162 rotates, the slider 163, which is screwed onto the ball screw 162, moves in the Y-axis direction along two guide rails 164. The aforementioned lifting and lowering section 15 is fixed to the slider 163. Therefore, when the slider 163 moves horizontally in the Y-axis direction, the lifting and lowering section 15, and the box 12, plate 11, and two-fluid nozzle 14 connected to this lifting and lowering section 15, move horizontally. The pair of upper and lower guide rails 164 are fixed to the gantry frame 24 of the base section 20, which will be described later, and extend in the Y-axis direction from the upper and lower parts of the ball screw 162, respectively. The configuration of the horizontal movement section 16 is arbitrary and only needs to move the plate 11 horizontally.

[0027] As described above, the air source 17 shown in Figure 5 supplies air to the two-fluid nozzle 14, and the water source 18 supplies water to the two-fluid nozzle 14. These air and water mix to produce two fluids F.

[0028] The control unit 19 includes a processor (e.g., CPU: Central Processing Unit) that functions as an arithmetic processing unit to control the operation of each part of the cleaning device 10, and a memory such as a ROM (Read Only Memory), which is a read-only semiconductor memory in which a predetermined control program is pre-recorded, and a RAM (Random Access Memory), which is a semiconductor memory that can be written to and read at any time and used as a working memory area as needed when the processor executes various control programs. The control unit 19 may be provided for each of the following: for example, the two-fluid nozzle 14, the lifting unit 15, the horizontal moving unit 16, etc., and the cleaning device 10 may have multiple control units 19. Furthermore, the control unit 19 of the cleaning device 10 may also serve as the control unit for other devices (e.g., the grinding mechanism 40). Alternatively, the control unit of another device may also serve as the control unit 19 of the cleaning device 10, or a control unit that controls both the cleaning device 10 and other devices may be provided.

[0029] The base section 20 shown in Figure 1 includes a base 21, a movable plate 22, a waterproof cover 23, a gantry frame 24, and a column 25.

[0030] The base 21 has a rectangular parallelepiped shape with its longitudinal direction in the X-axis direction. A portion of the upper surface of the base 21 has a rectangular opening that is long in the X-axis direction. A movable plate 22 is positioned in this opening so as to be movable in the X-axis direction. This movable plate 22 is positioned horizontally and has a rectangular frame shape that surrounds the chuck table 30, which will be described later, and moves in the X-axis direction together with the chuck table 30. A waterproof cover 23 is provided in a bellows-like shape to close the above-mentioned opening of the base 21. The gantry frame 24 includes two vertical portions that extend upward from a position separated in the Y-axis direction from the upper surface of the base 21, flanking the above-mentioned opening, and one horizontal portion that extends in the Y-axis direction, connecting the upper ends of these two vertical portions. A pair of upper and lower guide rails 164 of the above-mentioned horizontal movement section 16 are fixed to the horizontal portion of the gantry frame 24. The column 25 is positioned at the rear of the upper surface of the base 21. Column 25 has a rectangular parallelepiped shape with its longitudinal direction in the Z-axis direction.

[0031] The chuck table 30 has a frame 31 and a porous plate 32. The chuck table 30 rotates with the Z-axis as its center of rotation by a table rotation mechanism (not shown) located inside the base portion 20. The chuck table 30 also moves in the X-axis direction within the opening of the base 21 by a table movement mechanism (not shown) located inside the base portion 20.

[0032] The frame 31 has a disc shape, and as shown in Figure 5, a recess 311 is provided on its upper surface. The frame 31 also has a connecting passage 312 that extends from the recess 311 to the lower end of the chuck table 30. This connecting passage 312 is connected to a suction source (not shown) and functions as a suction path for drawing air from the recess 311.

[0033] The porous plate 32 is disc-shaped and is housed in the recess 311 of the frame 31. The porous plate 32 is made of a porous material such as ceramics, and fine pores are formed throughout it. With the porous plate 32 installed in the recess 311 of the frame 31, the upper surface of the frame 31 and the upper surface of the porous plate 32 are flush. The upper surface of the porous plate 32 constitutes a holding surface 321 that holds the wafer W by suction of air through the aforementioned communication passage 312.

[0034] The grinding mechanism 40 shown in Figure 1 includes a spindle 41, a spindle housing 42, a holder 43, a spindle motor 44, a mount 45, a grinding wheel 46, and a grinding wheel 47.

[0035] The spindle 41 rotates with the Z-axis as its center of rotation. The spindle housing 42 rotatably supports the spindle 41. The holder 43 is fixed to the slider 53 of the grinding lifting mechanism 50 (described later) and holds the spindle housing 42. The spindle motor 44 rotates the spindle 41. The mount 45 is attached to the lower end of the spindle 41. The grinding wheel 46 is mounted on the mount 45. The grinding wheel 47 is provided in an annular shape on the lower surface of the grinding wheel 46 and grinds the workpiece, such as a wafer W, which is held by suction on the holding surface 321 of the chuck table 30. The wafer W that has been ground moves in the X-axis direction together with the chuck table 30 so that it is positioned directly below the two-fluid nozzle 14.

[0036] The grinding lifting mechanism 50 includes a motor 51, a ball screw 52, ​​a slider 53, and a pair of guide rails 54, one on the left and one on the right.

[0037] The motor 51 is positioned at the upper end of the ball screw 52 and rotates the ball screw 52. The ball screw 52 is positioned in the Z-axis direction, and as the ball screw 52 rotates, a slider 53 that screws onto the ball screw 52 moves in the Z-axis direction along two guide rails 54. The holder 43 of the grinding mechanism 40 is fixed to this slider 53 as described above. The pair of left and right guide rails 54 are fixed to the column 25 described above and extend in the Z-axis direction on the right and left sides of the ball screw 52, ​​respectively.

[0038] Here, the ejection of the two fluids F in the cleaning apparatus 10 will be explained, omitting any details that overlap with the above explanation. In the example of Figure 5, the object to be cleaned is the porous plate 32 (chuck table 30), and in the example of Figure 6, it is the wafer W.

[0039] First, as shown in Figure 5, the control unit 19 controls the horizontal movement unit 16 to move the lifting unit 15, the box 12, plate 11, and two-fluid nozzle 14, which move horizontally (in the Y-axis direction) together with the lifting unit 15, in the Y-axis direction to any desired cleaning position of the two-fluid nozzle 14.

[0040] Next, the control unit 19 controls the lifting unit 15 to raise and lower the box 12, the plate 11 which moves up and down together with the box 12, and the two-fluid nozzle 14 so that the gap G between the lower surface of the plate 11 and the holding surface 321 of the porous plate 32 is a preset gap. This preset gap is often narrower than the height of the water layer of the two fluids F that would be formed on the holding surface 321 of the porous plate 32 if the plate 11 were not in place, and is, for example, 1 mm or 2 mm. If the upper surface of the object to be cleaned is not horizontal, the shape of the lower surface of the plate 11 may be parallel to the upper surface of the object to be cleaned rather than being flat. Also, the preset gap G may be larger or smaller as it moves away from the opening 111, depending on the shape of the upper surface of the object to be cleaned and the shape of the lower surface of the plate 11.

[0041] Next, the control unit 19 controls the two-fluid nozzle 14 and injects the two fluids F from the two-fluid nozzle 14. Since an opening 111 is formed in the plate 11 directly below the two-fluid nozzle 14, the two fluids F pass through the opening 111 and flow radially away from the opening 111 in the gap G between the holding surface 321 of the porous plate 32 and the lower surface of the plate 11, as shown in Figures 2 and 4, and clean the porous plate 32. This removes debris such as grinding chips from the holding surface 321. During the cleaning process, the two-fluid nozzle 14 may be moved in the Y-axis direction by the horizontal movement unit 16, or the chuck table 30 may be moved or rotated in the X-axis direction as appropriate.

[0042] Even when the object to be cleaned is a wafer W held by adsorption on the holding surface 321 of the chuck table 30 as shown in Figure 6, the operation of the cleaning device 10 is the same, and the cleaning by the cleaning device 10 removes debris such as grinding shavings from the upper surface Wa of the wafer W. After cleaning, the wafer W is transported to a storage cassette or other device by a robot arm (not shown).

[0043] As shown in Figure 6, an air source 61 and a water source 62 communicating with the passage 312 of the frame 31 may be arranged below the chuck table 30. In this case, the underside of the object to be cleaned (wafer W in Figure 6) can be cleaned with air supplied by the air source 61 and water supplied by the water source 62. Similarly, if the object to be cleaned is a porous plate 32 (chuck table 30), the porous plate 32 can be cleaned from below with air supplied by the air source 61 and water supplied by the water source 62.

[0044] In the embodiment described above, the cleaning device 10 is a cleaning device 10 that cleans the upper surface of an object to be cleaned (for example, a wafer W or a chuck table 30) by spraying a two-fluid mixture F of water and air from a two-fluid nozzle 14 positioned above the object to be cleaned, and comprises a plate 11 positioned above the upper surface of the object to be cleaned with a gap G, and an opening 111 formed in the plate 11 that allows the two-fluid mixture F sprayed from the two-fluid nozzle 14 to pass through without obstructing the area and be sprayed onto the object to be cleaned. After the two-fluid mixture F passes through the opening 111 and is sprayed onto the upper surface of the object to be cleaned, it flows radially away from the opening 111 through the gap G between the upper surface of the object to be cleaned and the lower surface of the plate 11, cleaning the object to be cleaned.

[0045] By arranging the plate 11 with the opening 111 formed in this manner, it is possible to suppress the formation of a water layer on the upper surface of the object to be cleaned, which would otherwise hinder the force of the two fluids F. Furthermore, since the flow path of the two fluids F sprayed onto the object to be cleaned is partitioned in the gap G between the plate 11 and the upper surface of the object to be cleaned, the two fluids F can flow more easily over the upper surface of the object to be cleaned. Therefore, the force of the two fluids F is not hindered, and a decrease in cleaning power is prevented. Thus, according to this embodiment, the cleaning time can be shortened. Moreover, by arranging the plate 11, it is also possible to suppress the splashing and scattering of the two fluids F sprayed from the two-fluid nozzle 14 away from the object to be cleaned.

[0046] In this embodiment, the cleaning device 10 comprises a box 12 surrounding the two-fluid nozzle 14, for example, four side plates 121 surrounding the two-fluid nozzle 14, and a top plate 122 connected to the upper ends of the side plates 121, and exhaust ports 123 formed in the side plates 121 (or top plate 122), and the plate 11 is connected to the lower end of the box 12.

[0047] Therefore, the increase in air pressure inside the box 12 caused by the injection of the two fluids F from the two-fluid nozzle 14 can be suppressed by the exhaust from the exhaust port 123. This prevents the injection of the two fluids F by the two-fluid nozzle 14 from being hindered by the increase in air pressure inside the box 12. Consequently, the cleaning time can be shortened even further.

[0048] Furthermore, in this embodiment, the cleaning device 10 includes a lifting unit 15, which is an example of a lifting means for raising and lowering the plate 11. The object to be cleaned is the holding surface 321 of the table (e.g., chuck table 30) or the upper surface of the workpiece (e.g., wafer W) held on the holding surface 321. The cleaning device 10 includes a control unit 19 that controls the lifting unit 15 so that the gap G between the holding surface 321 of the chuck table 30 and the lower surface of the plate 11, and the gap G between the upper surface Wa of the wafer W and the lower surface of the plate 11, are set to preset gaps.

[0049] This allows the gap G between the lower surface of the plate 11 and the upper surface of the object to be cleaned to be adjusted in accordance with the ease of flow of the two fluids F, which varies depending on factors such as the amount of two fluids F injected and the material of the plate 11 and the object to be cleaned. As a result, the two fluids F injected by the two-fluid nozzle 14 can flow more easily through the gap G between the plate 11 and the object to be cleaned, further shortening the cleaning time.

[0050] In this embodiment, the plate 11 has an area smaller than the surface to be cleaned, but it may have an area larger than the surface to be cleaned. By arranging a plate 11 with an area larger than the surface to be cleaned, a gap G is formed across the entire surface to be cleaned, and the two fluids F are discharged from the outer periphery of the surface to be cleaned, thereby preventing the dirt removed from the surface from re-adhering to the surface.

[0051] It goes without saying that the cleaning apparatus according to the present invention is not limited to the embodiments described above, and may be implemented in various different forms within the scope of its technical concept. Furthermore, the shapes of each component shown in the attached drawings are not limited thereto and can be appropriately modified within the scope that allows the effects of the present invention to be achieved. [Industrial applicability]

[0052] As described above, the present invention enables a cleaning device that sprays a two-fluid mixture F of water and air, thereby shortening the cleaning time. Therefore, it is particularly useful for cleaning workpieces such as wafers and for cleaning chuck tables that adsorb and hold workpieces. [Explanation of Symbols]

[0053] 10: Washing device 11: Plate 111:Aperture 12:Box 121: Side panel 122: Tabletop 123: Exhaust vent 14:2 Fluid Nozzle 15: Lifting mechanism (lifting means) 151: Rod 16: Horizontal movement part (transportation means) 161: Motor 162: Ball screw 163: Slider 164: Guide rail 17: Air source 18: Water source 19: Control Unit 20: Base section 21: Base 22: Mobile board 23: Waterproof cover 24: Gate-type frame 25: Column 30: Chuck Table 31:Frame body 311: Recess 312: Communication path 32: Porous plate 321: Holding surface 40: Grinding mechanism 41: Spindle 42: Spindle Housing 43: Holder 44: Spindle motor 45: Mount 46: Grinding Wheel 47: Sharpening stone 50: Grinding lifting mechanism 51: Motor 52: Ball screw 53: Slider 54: Guide rail 61: Air source 62: Water source F:2 fluid G: Gap W: Wafer Wa: Top surface

Claims

1. A cleaning device that cleans the upper surface of an object to be cleaned by spraying a mixture of water and air from two fluid nozzles positioned above the object to be cleaned, A plate is positioned above the upper surface of the object to be cleaned, leaving a gap between them. The plate is provided with an opening formed therein that allows the two fluids sprayed from the two-fluid nozzle to pass through without obstructing the area and be sprayed onto the object to be cleaned, The device comprises a box surrounding the two fluid nozzles, a side plate surrounding the two fluid nozzles, and a top plate connected to the upper end of the side plate, and an exhaust port formed in the top plate or the side plate. The plate is connected to the lower end of the box, A cleaning device in which two fluids passing through the opening are sprayed onto the upper surface of the object to be cleaned, and then flow radially away from the opening through the gap between the upper surface of the object to be cleaned and the lower surface of the plate to clean the object.

2. The plate is equipped with a lifting mechanism for raising and lowering it, The object to be cleaned is the holding surface of the table or the upper surface of the workpiece held on the holding surface, The system includes a control unit that controls the lifting mechanism so that the gap between the holding surface and the lower surface of the plate, and the gap between the upper surface of the workpiece and the lower surface of the plate, become preset gaps. The cleaning apparatus according to claim 1.

3. A method for manufacturing a wafer, comprising cleaning a wafer, which is an object to be cleaned, using the cleaning apparatus described in Claim 1, A holding process in which the wafer is held on the holding surface of the chuck table, A method for manufacturing a wafer, comprising a cleaning step of cleaning the upper surface of a wafer held on the holding surface with two fluids sprayed from the two-fluid nozzle of the cleaning apparatus.

4. The method for manufacturing a wafer according to claim 3, further comprising a holding surface cleaning step, in which the holding surface is cleaned with two fluids sprayed from the two-fluid nozzle of the cleaning device before the holding step.

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