Processing device

Abstract

To provide a processing device which enables improvement of cleaning effect of a workpiece.SOLUTION: A processing device 1 includes a grinding unit 20 which rotates a processing tool, which is formed by a grinding wheel 21 in which grinding stones 212 are disposed in an annular form, to process a workpiece held by a holding table. The grinding unit 20 includes: a spindle 22 which is connected at a lower end with a mount 221 to which the grinding wheel 21 is rotatably attached; and a fluid supply part 50. The fluid supply part 50 includes: a first communication passage 51 penetrating through the spindle 22 and allowing communication between a first fluid supply source 54 and a discharge port 53 of the mount 221 attached to the spindle 22; and a second communication passage 52 penetrating through the spindle 22 and allowing communication between a second fluid supply source 55 and the discharge port 53 of the mount 221 attached to the spindle 22. The discharge port 53 may supply a mixed fluid formed by mixing a first fluid 541 with a second fluid 551.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a processing device for processing a workpiece. [Background technology]

[0002] Grinding machines (processing machines) are used to grind workpieces such as semiconductor wafers. Grinding machines have a grinding wheel with grinding stones arranged in a ring, attached to a mount at the tip of a spindle.

[0003] The grinding machine grinds the workpiece held on a holding table by bringing a grinding wheel, which rotates together with the spindle, into contact with the workpiece. In the grinding machine, grinding water is supplied to the inner peripheral surface of the grinding wheel to remove grinding dust and heat generated during the grinding process (see, for example, Patent Document 1).

[0004] For example, in the grinding device shown in Patent Document 1, grinding water is supplied from the center of the spindle toward the workpiece held on the holding table below by a grinding water supply means connected to a through hole passing through the center of the spindle. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-221636 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the grinding device shown in Patent Document 1, the grinding water supplied from the grinding water supply means is pure water that is supplied so that it falls freely from above to below. Therefore, although it is effective in removing heat generated during grinding, it has the problem that it is not very effective in removing or cleaning grinding chips.

[0007] Therefore, there is a need to provide a processing apparatus that processes a workpiece with a processing tool, which has a relatively high cleaning effect on the workpiece held on the holding table.

[0008] An object of the present invention is to provide a processing apparatus that can improve the cleaning effect of a workpiece. [Means for solving the problem]

[0009] In order to solve the above-mentioned problems and achieve the object, the processing apparatus of the present invention is a processing apparatus comprising: a holding table for holding a workpiece; a processing unit disposed above the holding table for rotating a processing tool consisting of a grinding wheel with grinding stones arranged in an annular shape or a polishing pad with a through hole in the center to process the workpiece held by the holding table; and a moving unit for moving the holding table and the processing unit in directions in which they approach and move apart relatively, and the processing unit has a mount for rotatably mounting the processing tool, the center of the mount being aligned with the axis of the mount, connected to the lower end. the mount is provided with a spindle in contact with the spindle, a fluid supply unit disposed in the rotational center region of the mount and supplying fluid downward, a first communication passage penetrating the rotational center region of the spindle and communicating between a first fluid supply source and the fluid supply unit of the mount attached to the spindle, and a second communication passage penetrating the rotational center region of the spindle and communicating between a second fluid supply source and the fluid supply unit of the mount attached to the spindle, wherein the fluid supply unit is capable of supplying a mixed fluid obtained by mixing a first fluid supplied from the first fluid supply source and a second fluid supplied from the second fluid supply source.

[0010] The processing apparatus may further include a control unit, which controls the fluid supply unit to select and supply the fluid from the first fluid, the second fluid, and the mixed fluid.

[0011] In the processing device, the first fluid may be water and the second fluid may be air.

[0012] In the processing apparatus, the discharge port of the fluid supply unit that supplies the fluid downward may be divergent downward. [Effects of the Invention]

[0013] The present invention has an effect of improving the cleaning effect of the workpiece. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view showing an example of the configuration of a processing device according to the first embodiment. [Figure 2] FIG. 2 is a perspective view schematically showing a state in which the processing apparatus shown in FIG. 1 grinds a workpiece. [Figure 3] FIG. 3 is a side view, partly in section, schematically showing the configuration of the grinding unit of the processing apparatus shown in FIG. [Figure 4] FIG. 4 is a perspective view showing a configuration example of a processing device according to a first modification of the first embodiment. [Figure 5] FIG. 5 is a side view, partially in section, schematically showing the configuration of a polishing unit of a processing apparatus according to a second modification of the first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] Modes (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially the same. Furthermore, the configurations described below can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the configuration can be made within the scope of the gist of the present invention.

[0016] [Embodiment 1] A processing apparatus according to a first embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a perspective view showing an example of the configuration of the processing apparatus according to the first embodiment. Fig. 2 is a perspective view schematically showing a state in which the processing apparatus shown in Fig. 1 grinds a workpiece. Fig. 3 is a side view, partially in cross section, schematically showing the configuration of a grinding unit of the processing apparatus shown in Fig. 1.

[0017] (Workpiece) 1 according to the first embodiment is a grinding apparatus that grinds (corresponding to processing) a workpiece 200. The workpiece 200 to be processed by the processing apparatus 1 according to the first embodiment is, for example, a disk-shaped semiconductor wafer having a substrate made of silicon, sapphire, gallium, SiC, or the like, or a wafer such as an optical device wafer. The workpiece 200 has a surface 201 divided into a grid pattern by a plurality of mutually intersecting planned division lines, and devices are formed in each of the regions.

[0018] The device is, for example, an integrated circuit such as an IC (Integrated Circuit) or an LSI (Large Scale Integration), an image sensor such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor), or a memory (semiconductor storage device). A tape 210 having the same diameter as the workpiece 200 is attached to a front surface 201 of the workpiece 200, and a back surface 202 behind the front surface 201 is ground.

[0019] (Processing equipment) 1 according to the first embodiment is a grinding device that grinds a rear surface 202 of a workpiece 200. The processing device 1 according to the first embodiment is a grinding device that grinds an area corresponding to a device on the rear surface 202 of the workpiece 200 (an area that overlaps in the thickness direction with an area on the front surface 201 where the device is formed) to form a circular recess 203 and an annular protrusion 204 surrounding the circular recess 203, as shown in FIG.

[0020] As described above, the processing apparatus 1 according to the first embodiment is a grinding apparatus that performs so-called TAIKO (registered trademark) grinding on the workpiece 200. The circular recess 203 is formed in an area corresponding to a device on the rear surface 202 of the workpiece 200, and the annular protrusion 204 is formed in an area corresponding to a peripheral surplus area on the rear surface 202 of the workpiece 200 where no devices are formed, and the circular recess 203 and the annular protrusion 204 are arranged coaxially. The area corresponding to the peripheral surplus area is an area that overlaps in the thickness direction with the peripheral surplus area that surrounds the area on the front surface 201 where the devices are formed.

[0021] As shown in FIG. 1, the processing apparatus 1 includes an apparatus base 2, a holding table 10, a grinding unit 20, a processing feed unit 30, a grinding feed unit 40, and a control unit 100.

[0022] The holding table 10 holds the workpiece 200 with a holding surface 11 holding the front surface 201 side on which the device is formed, leaving the back surface 202 of the workpiece 200 exposed. The holding table 10 is disk-shaped, and the holding surface 11 that holds the workpiece 200 is made of porous ceramic or the like.

[0023] The holding table 10 has a holding surface 11 connected to a suction source (not shown), and the holding surface 11 is sucked by the suction source, thereby suction-holding the workpiece 200 placed on the holding surface 11. The holding table 10 is also rotatable about an axis parallel to the Z-axis direction by a rotation drive source (not shown). The Z-axis direction is parallel to the vertical direction (also referred to as the up-down direction) and is perpendicular to the holding surface 11. The holding table 10 suction-holds the workpiece 200 on the holding surface 11, and is rotated about the axis by the rotation drive source, thereby supporting the workpiece 200 so that it can rotate about the axis.

[0024] The grinding unit 20 is a processing unit that rotates a grinding wheel 21, which is a processing tool, around its axis to grind a workpiece 200 held by the holding table 10. The grinding unit 20 is supported by an upright column 3 that stands upright from one end of the device base 2 in the Y-axis direction parallel to the horizontal direction, via a grinding feed unit 40.

[0025] As shown in Figure 3, the grinding unit 20 has a spindle 22 extending along the Z-axis direction, a spindle motor 23 that rotates the spindle 22 around its axis, a spindle housing 24 (corresponding to a casing) that holds the spindle 22 rotatably around its axis, and a grinding wheel 21.

[0026] The spindle 22 is formed in a cylindrical shape with its axis aligned along the Z-axis direction, which is the up-down direction. A disk-shaped mount 221, to which the grinding wheel 21 can be attached, is disposed at the lower end of the spindle 22, which is the tip. In other words, the spindle 22 can have the grinding wheel 21 disposed at its lower end. The spindle 22 is disposed coaxially with the mount 221. In this way, the spindle 22 is connected to the mount 221 at its lower end with the center of the mount 221 coinciding with the axis of the spindle 22.

[0027] In the first embodiment, as shown in Fig. 3, the spindle 22 includes a cylindrical small diameter portion 222 and a cylindrical large diameter portion 223 that are coaxially arranged. In the first embodiment, the spindle 22 includes two small diameter portions 222 and two large diameter portions 223. In the first embodiment, one of the large diameter portions 223 is attached to the mount 221, and one of the small diameter portions 222 is disposed between the large diameter portions 223, so that the large diameter portions 223 and the small diameter portions 222 are alternately disposed in the axial direction. In the first embodiment, the outer diameter of the large diameter portion 223 is equal to the outer diameter of the mount 221.

[0028] The spindle motor 23 is attached to the upper end (corresponding to the base end) of the spindle 22. In the first embodiment, the spindle motor 23 includes a rotor 231 attached to the outer peripheral surface of the other small diameter portion 222, and a stator 232 attached to the inner peripheral surface of the spindle housing 24 via a cooling jacket 25. When power is applied to the coil of the stator 232, the rotor 231, i.e., the spindle 22, rotates around the axis.

[0029] The cooling jacket 25 includes a cooling water passage 251 for circulating cooling water to cool the stator 232 of the spindle motor 23 and the like.

[0030] The spindle housing 24 is cylindrically formed and includes a cylindrical portion 241 that surrounds the outer peripheral surfaces of the small diameter portion 222 and the other large diameter portion 223 of the spindle 22, a disk-shaped disk portion 242 that closes the upper end of the cylindrical portion 241, and a spindle cover 243. The cylindrical portion 241 has an inner diameter larger than the outer diameter of the large diameter portion 223 of the spindle 22. The disk portion 242 has an outer diameter equal to the outer diameter of the cylindrical portion 241. The spindle housing 24 accommodates the small diameter portion 222 and the other large diameter portion 223 of the spindle 22 within the cylindrical portion 241 and supports the spindle 22 rotatably about its axis via an air bearing 26.

[0031] Air bearing 26 includes an annular intrusion portion 261 that intrudes between large diameter portions 223 of spindle 22, air outlets 262 that open to the upper surface, lower surface and inner circumferential surface of intrusion portion 261, and an air supply path 263 that is provided inside spindle housing 24 and communicates with air outlet 262. Intrusion portion 261 is provided integrally with cylindrical portion 241 on the inner circumferential surface of cylindrical portion 241, and has an inner diameter larger than the outer diameter of small diameter portions 222 and a thickness thinner than the distance between large diameter portions 223.

[0032] A plurality of air outlets 262 are provided at equal intervals in the radial and circumferential directions on the upper surface of the intrusion portion 261. A plurality of air outlets 262 are provided at equal intervals in the radial and circumferential directions on the lower surface of the intrusion portion 261. A plurality of air outlets 262 are provided at equal intervals in the circumferential direction on the inner peripheral surface of the intrusion portion 261.

[0033] The air supply passage 263 is a passage provided inside the spindle housing 24, and is supplied with compressed air from an air supply source 264. The air bearing 26 ejects the compressed air supplied from the air supply source 264 from an air outlet 262 through the air supply passage 263, thereby supporting the spindle 22 rotatably about its axis.

[0034] The spindle cover 243 is formed in a cylindrical shape with inner and outer diameters equal to those of the spindle housing 24. The spindle cover 243 is attached to the lower end of the spindle housing 24 and accommodates one of the large diameter portions 223 of the spindle 22. In the first embodiment, the spindle cover 243 is disposed coaxially with the spindle housing 24.

[0035] The grinding wheel 21 is attached to the underside of the mount 221. That is, the mount 221 rotatably attaches the grinding wheel 21. The grinding wheel 21 includes a wheel base 211 formed in an annular shape and attached to the underside of the mount 221, and a plurality of grinding stones 212 arranged in an annular shape on the underside of the wheel base 211. The grinding stones 212 are arranged at equal intervals in the circumferential direction of the wheel base 211, and a plurality of grinding stones 212 are fixed to the underside of the wheel base 211.

[0036] The grinding wheel 212 is configured as a so-called segment grinding wheel formed into a single mass by mixing abrasive grains such as diamond or CBN (Cubic Boron Nitride) with a bonding material (also called a bond material) made of metal, ceramic, resin, etc. The grinding wheel 212 grinds the back surface 202 of the workpiece 200. In the first embodiment, the grinding wheel 21 is used for TAIKO grinding, so the diameter of the circle formed by connecting the outer edges of the grinding wheel 212 is smaller than the radius of the workpiece 200.

[0037] The processing feed unit 30 is installed on the device base 2, and moves the holding table 10 relative to the grinding unit 20 in the Y-axis direction, which is the processing feed direction parallel to the holding surface 11. By moving the holding table 10 in the Y-axis direction, the processing feed unit 30 moves the holding table 10 between a carry-in / out position where the workpiece 200 is carried in and out of the holding table 10, away from the grinding unit 20, and a processing position below the grinding unit 20 where the workpiece 200 is ground by the grinding unit 20. In other words, the grinding unit 20 is disposed above the holding table 10 positioned at the processing position.

[0038] The grinding feed unit 40 is attached to an upright column 3 that stands upright from the device base 2, and is a moving unit that moves the grinding unit 20 in the Z-axis direction, which is the vertical direction perpendicular to the holding surface 11. In other words, the grinding feed unit 40 is a moving unit that moves the holding table 10 and the grinding unit 20 in directions that bring them closer to and away from each other. The grinding feed unit 40 lowers the cylindrical holding member 28 attached to the spindle housing 24 of the grinding unit 20 to bring the grinding wheel 212 closer to the workpiece 200 held on the holding table 10 at the processing position, and raises the holding member 28 to move the grinding wheel 212 away from the workpiece 200 held on the holding table 10 at the processing position.

[0039] The machining feed unit 30 and the grinding feed unit 40 are equipped with a well-known ball screw that is rotatable around its axis, a well-known pulse motor that rotates the ball screw around its axis, and a well-known guide rail that supports the holding table 10 or the grinding unit 20 so that it can move freely in the X-axis or Z-axis direction.

[0040] 1 and 3, the grinding unit 20 of the processing apparatus 1 is provided with a fluid supply unit 50 that is disposed in the rotation center region of the mount 221 and supplies fluid below the grinding wheel 21. The rotation center region of the spindle 22 and the mount 221 refers to the region within the small diameter portion 222 of the spindle 22 and on the inner circumferential side of the wheel base 211 of the grinding wheel 21, for example, a region within ½ of the radius from the axis of the small diameter portion 222 in the radial direction, preferably a region within ⅓ of the radius, and more preferably a region within ¼ of the radius.

[0041] The fluid supply unit 50 includes a first communication passage 51, a second communication passage 52, and a discharge port 53. The first communication passage 51 is a flow path that passes through the rotation center region of the spindle 22 along the axis of the spindle 22. The first communication passage 51 is a flow path that communicates between a first fluid supply source 54 that supplies a first fluid 541 and a discharge port 53 that is attached to a mount 221 that is attached to the spindle 22.

[0042] The second communication passage 52 is a flow path that passes through the rotation center region of the spindle 22 along the axis of the spindle 22. The second communication passage 52 is a flow path that communicates between a second fluid supply source 55 that supplies a second fluid 551 and a discharge port 53 that is attached to a mount 221 that is attached to the spindle 22.

[0043] The first fluid supply source 54 supplies water, which is a liquid, as the first fluid 541. The second fluid supply source 55 supplies air, which is a gas, as the second fluid 551. Thus, in this embodiment, the first fluid 541 is water, and the second fluid 551 is air.

[0044] The discharge port 53 supplies fluids 541 and 551 from the first fluid supply source 54 and the second fluid supply source 55 to the inner peripheral side of the grinding stone 212 arranged in an annular shape below the grinding wheel 21. In the first embodiment, the discharge port 53 is attached to the lower surface of the mount 221 and is formed in a cylindrical shape with the inside communicating with the communication passages 51 and 52. The discharge port 53 is formed in a flared shape with its inner and outer diameters gradually increasing downward.

[0045] The control unit 100 controls each of the above-mentioned components constituting the machining apparatus 1. That is, the control unit 100 causes the machining apparatus 1 to execute a machining operation on the workpiece 200. The control unit 100 is a computer that has an arithmetic processing device having a microprocessor such as a CPU (central processing unit), a storage device having a memory such as a ROM (read only memory) or RAM (random access memory), and an input / output interface device, and is capable of executing a computer program.

[0046] The arithmetic processing unit of the control unit 100 executes a computer program stored in the ROM on the RAM to generate control signals for controlling the machining device 1. The arithmetic processing unit of the control unit 100 outputs the generated control signals to each component of the machining device 1 via the input / output interface device. The control unit 100 is also connected to a display means (not shown) configured by a liquid crystal display device or the like for displaying the status and images of the machining operation, and to an input means used by the operator to register machining conditions. The input means is configured by at least one of a touch panel provided on the display means, a keyboard, or the like.

[0047] (Machining operation) Next, a description will be given of the processing operation of the processing device 1 according to embodiment 1. In the processing device 1 having the above-described configuration, an operator or the like places the front surface 201 side of the workpiece 200 before grinding on the holding surface 11 of the holding table 10 at the carry-in / out position via tape 210, and the control unit 100 receives the processing conditions input by the operator or the like. The processing device 1 starts the processing operation when the control unit 100 receives the instruction to start the processing operation input by the operator.

[0048] When the machining operation is started, the control unit 100 of the machining apparatus 1 supplies compressed air from the air supply source 264 to the air supply path 263 of the spindle housing 24, and drives the spindle motor 23 to start rotating the spindle 22 and the grinding wheel 21 about their axes. Also, when the machining operation is started, the control unit 100 of the machining apparatus 1 operates the suction source to suck and hold the front surface 201 of the workpiece 200 on the holding surface 11 of the holding table 10, thereby exposing the back surface 202 of the workpiece 200 upward. During the machining operation, the control unit 100 controls the machining feed unit 30 to move the holding table 10, which is sucking and holding the workpiece 200, to the machining position.

[0049] In the machining operation, the control unit 100 of the machining apparatus 1 rotates the holding table 10 about its axis while discharging the first fluid 541 from only the first fluid supply source 54 through the first communication passage 51 and from the discharge port 53 at the machining position, and controls the grinding feed unit 40 to lower the grinding wheel 21 rotated about its axis. In the first embodiment, the machining apparatus 1 discharges the first fluid 541 from the discharge port 53 at a pressure of about 0.2 MPa (gauge pressure).

[0050] In the processing operation, the processing apparatus 1 brings the grinding stone 212 of the grinding wheel 21 rotating about its axis into contact with the back surface 202 of the workpiece 200 held on the holding table 10 rotating about its axis while supplying the first fluid 541, which is water, and grinds the back surface 202 of the workpiece 200 with the grinding stone 212. Thus, in the first embodiment, the processing apparatus 1 performs TAIKO grinding on the central portion of the back surface 202 of the workpiece 200, forming a circular recess 203 and an annular protrusion 204 on the back surface 202 of the workpiece 200, as shown in FIG.

[0051] In the processing operation, when the grinding wheel 212 thins the workpiece 200 to a predetermined thickness to form the circular recess 203, the control unit 100 controls the grinding feed unit 40 to raise the grinding wheel 21. At this time, the control unit 100 of the processing apparatus 1 supplies a first fluid 541 from the first fluid supply source 54 to the first communication passage 51, supplies a second fluid 551 from the second fluid supply source 55 to the second communication passage 52, mixes the first fluid 541 and the second fluid 551 at the discharge port 53, and discharges the mixed fluid of the first fluid 541, which is water, and the second fluid 551, which is air, from the discharge port 53.

[0052] In the first embodiment, the processing apparatus 1 discharges a mixed fluid of a first fluid 541 having a pressure of about 0.2 MPa (gauge pressure) and a second fluid 551 having a pressure of 0.3 MPa (gauge pressure) or more and about 0.5 MPa (gauge pressure) from the discharge port 53. The mixed fluid discharged from the discharge port 53 becomes atomized droplets, and when the droplets collide with the back surface 202 of the workpiece 200, shock waves and expansion waves are generated inside the droplets, centered at the point of contact with the workpiece 200. Furthermore, the droplets of the mixed fluid generate a jet water flow that flows along the back surface 202 of the workpiece 200.

[0053] When the droplets of the mixed fluid directly collide with the fine particles, the fine particles are pulled off from the back surface 202 of the workpiece 200 due to pressure fluctuations inside the droplets, and even when the droplets of the mixed fluid do not directly collide with the fine particles, the fine particles are washed away by the jet water flow, and the first fluid 541 containing grinding debris is washed away from the back surface 202, particularly from inside the circular recess 203. In this way, the mixed fluid discharged from the discharge port 53 has a higher cleaning effect on the back surface 202 of the workpiece 200 than the first fluid 541 discharged from the discharge port 53 alone.

[0054] In the processing operation, the processing device 1 discharges the mixed fluid from the discharge port 53 for a predetermined time after starting to lift the grinding wheel 21, and then the control unit 100 stops the supply of the first fluid 541 from the first fluid supply source 54 and discharges the second fluid 551 only from the second fluid supply source 55 through the second communication passage 52 from the discharge port 53 to dry the back surface 202 of the workpiece 200 held on the holding table 10. In the first embodiment, the processing device 1 discharges the second fluid 551 from the discharge port 53 at a pressure of 0.3 MPa (gauge pressure) or more and about 0.5 MPa (gauge pressure).

[0055] In this way, the control unit 100 controls the fluid supply section 50 so that the fluid to be supplied from the fluid supply section 59 is selected from the first fluid 541, the second fluid 551, and a mixed fluid of the first fluid 541 and the second fluid 551.

[0056] In the processing operation, the control unit 100 of the processing device 1 stops the rotation of the holding table 10 about its axis, and the control unit 100 controls the processing feed unit 30 to transport the holding table 10, which holds by suction the ground workpiece 200, to the carry-in / out position. In the processing operation, the processing device 1 stops the suction holding of the holding table 10 at the carry-in / out position, and ends the processing operation.

[0057] As described above, the processing apparatus 1 of embodiment 1 has a grinding unit 20 arranged in the rotation center area of ​​the mount 221 and equipped with a fluid supply section 50 that supplies fluid to the workpiece 200 or holding table 10 below, and the fluid supply section 50 has a first communication passage 51 that penetrates the rotation center area of ​​the spindle 22 and connects between a first fluid supply source 54 and an outlet 53 of the fluid supply section 50 of the mount 221 attached to the spindle 22, and a second communication passage 52 that penetrates the rotation center area of ​​the spindle 22 and connects between a second fluid supply source 55 and an outlet 53 of the fluid supply section 50 of the mount 221 attached to the spindle 22, and the outlet 53 of the fluid supply section 50 is capable of discharging a mixed fluid obtained by mixing the first fluid 541 and the second fluid 551.

[0058] Therefore, the processing apparatus 1 according to embodiment 1 can supply a mixed fluid to the workpiece 200 held on the holding table 10, thereby providing a processing apparatus 1 with a relatively high cleaning effect, thereby achieving the effect of improving the cleaning effect of the workpiece 200.

[0059] [Modification] A processing apparatus according to a modification of the first embodiment will be described with reference to the drawings. Fig. 4 is a perspective view showing an example of the configuration of a processing apparatus according to a first modification of the first embodiment. Fig. 5 is a side view, partially in cross section, showing a schematic configuration of a polishing unit of a processing apparatus according to a second modification of the first embodiment. In Figs. 4 and 5, the same parts as those in the first embodiment are designated by the same reference numerals, and their description will be omitted.

[0060] In the present invention, as shown in Fig. 4, the diameter of the circle formed by connecting the outer edges of the grinding stones 212 of the grinding wheel 21 of the grinding unit 20, which is a processing unit, may be equal to the diameter of the workpiece 200, in which case the entire back surface 202 of the workpiece 200 may be ground. Also, in the present invention, as shown in Fig. 5, the processing apparatus 1 may be a polishing apparatus that polishes the back surface 202 of the workpiece 200. In the case of Fig. 5, the processing apparatus 1 preferably includes a polishing unit 20-2 as a processing unit, and the polishing unit 20-2 preferably includes a polishing wheel 21-2 as a processing tool that includes an annular wheel base 211-2 and a polishing pad 212-2 that is attached to the wheel base 211-2 and has a through hole 213 in its center.

[0061] The present invention is not limited to the above-described embodiment. In other words, various modifications can be made without departing from the gist of the present invention. In the present invention, the processing device 1 may include a rough grinding unit as a processing unit and a finish grinding unit as a processing unit. In this case, a mixed fluid of the first fluid 541 and the second fluid 551 is discharged from the discharge port 53 when the grinding wheel 21 of the finish grinding unit is lowered to clean the contaminated first fluid 541 from the circular recess 203 after processing by the rough grinding unit. [Explanation of symbols]

[0062] 1 Processing equipment 10 Holding table 20 Grinding unit (processing unit) 21 Grinding wheels (machining tools) 22 Spindle 40 Grinding feed unit (moving unit) 50 Fluid supply section 51 1st communication passage 52 2nd communication passage 53 Discharge port 54 First fluid supply source 55 Second fluid supply source 100 control unit 200 Workpiece 221 Mount

Claims

1. a holding table for holding the workpiece; a processing unit disposed above the holding table, which processes the workpiece held by the holding table by rotating a processing tool consisting of a grinding wheel with grinding stones arranged in an annular shape or a polishing pad with a through hole in the center; a moving unit that moves the holding table and the processing unit in directions in which they approach and move away from each other; A processing device comprising: The processing unit comprises: a spindle having a mount for rotatably mounting the machining tool and connected to a lower end thereof with the center of the mount and its axis aligned; a fluid supply portion disposed in a rotation center region of the mount and supplying a fluid downward; a first communication passage that passes through a rotation center region of the spindle and communicates between a first fluid supply source and the fluid supply portion of the mount attached to the spindle; a second communication passage that passes through a rotation center region of the spindle and communicates between a second fluid supply source and the fluid supply portion of the mount attached to the spindle; Equipped with The processing apparatus is characterized in that the fluid supply unit is capable of supplying a mixed fluid obtained by mixing a first fluid supplied from the first fluid supply source and a second fluid supplied from the second fluid supply source.

2. Further comprising a control unit; 2. The processing apparatus according to claim 1, wherein the control unit controls the fluid supply unit to supply a fluid selected from the first fluid, the second fluid, and the mixed fluid.

3. 3. The processing apparatus according to claim 1, wherein the first fluid is water and the second fluid is air.

4. 2. The processing apparatus according to claim 1, wherein the fluid supply portion has a discharge port that supplies the fluid downward and that diverges downward.

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