Grinding equipment and processing equipment

Abstract

To keep the distance between a surface to be washed and an injection port of a nozzle constant to always properly perform washing in a grinding device having a two-fluid washing mechanism.SOLUTION: A grinding device 1 includes a chuck table 30 that holds a workpiece 90 on a holding surface 302, a grinding mechanism 5 that grinds the workpiece 90 held on the holding surface 302 with a grinding wheel 541, a top surface height measuring device 382 that measures the top surface height of the workpiece 90 held on the holding surface 302, a two-fluid nozzle 71 that has an injection port 710 and injects two fluids in which water and air are mixed, a nozzle height adjustment mechanism 6 that adjusts the height of the two-fluid nozzle 71, and a first control unit 81 that controls the nozzle height adjustment mechanism 6 such that the distance between the top surface of the workpiece 90 held by the holding surface 302 and the injection port 710 is the preset first distance on the basis of the value measured by the top surface height measuring device 382.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a processing apparatus such as a grinding apparatus for grinding a workpiece such as a semiconductor wafer. [Background technology]

[0002] For example, in a grinding device such as those disclosed in Patent Document 1, Patent Document 2, or Patent Document 3, a wafer ground with a grinding wheel is held on a chuck table, and two fluids, a mixture of water and air, are sprayed from a nozzle onto the upper surface of the wafer to clean it. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-200785 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-135343 [Patent Document 3] Japanese Patent Publication No. 2020-116665 Summary of the Invention [Problem to be solved by the invention]

[0004] When cleaning wafers, the nozzle is positioned at a cleaning position above the chuck table. The nozzle moves up and down using a lifting mechanism between two positions: a cleaning position where the wafer is cleaned, and a retracted position. Therefore, even if the thickness of the ground wafer varies greatly, the nozzle is positioned at a fixed cleaning position for cleaning, and the distance between the top surface of the wafer and the nozzle may become closer or farther. This can lead to the problem of some areas of the wafer being unable to be cleaned. In addition, there are times when it is necessary to clean the holding surface of the chuck table with the two fluids sprayed from the nozzle.

[0005] Therefore, processing equipment such as grinding equipment equipped with a dual-fluid cleaning mechanism that sprays two fluids from a nozzle for cleaning has a problem of maintaining a desired constant distance between the surface to be cleaned and the nozzle outlet so that cleaning can always be performed appropriately. [Means for solving the problem]

[0007] The present invention, which solves the above-mentioned problems, is a processing apparatus comprising: a chuck table which holds a workpiece on a holding surface; a processing mechanism which is provided with a processing tool and processes the top surface of the workpiece held on the holding surface to reduce its thickness; a thickness measurement unit which measures the thickness of the workpiece held on the holding surface; a spinner cleaning mechanism which cleans the top surface of the workpiece machined by the processing tool; a transport mechanism which transports the workpiece from the chuck table to the spinner cleaning mechanism; and a spinner control unit, wherein the thickness measurement unit comprises an top surface height measuring device which measures the height of the top surface of the workpiece held on the holding surface; a holding surface height measuring device which measures the height of the holding surface; and a calculation unit which calculates the difference between the value of the top surface height measuring device and the value of the holding surface height measuring device as the thickness of the workpiece, The cleaning mechanism comprises a spinner holding mechanism that holds the workpiece and rotates around the center of the workpiece, a spinner two-fluid nozzle that sprays a mixture of water and air from a spinner nozzle onto the top surface of the workpiece held by the spinner holding mechanism, and a spinner nozzle height adjustment mechanism that adjusts the height of the spinner two-fluid nozzle.The spinner control unit comprises a setting unit that pre-sets a distance suitable for cleaning between the surface to be cleaned and the spinner nozzle, and controls the spinner nozzle height adjustment mechanism based on the value set in the setting unit and the value measured by the thickness measurement unit so that the distance between the top surface of the workpiece held by the spinner holding mechanism and the spinner nozzle becomes the pre-set distance, thereby cleaning the top surface of the workpiece held by the spinner holding mechanism. [Effects of the Invention]

[0008] The grinding apparatus according to the present invention controls the nozzle height adjustment mechanism using a first control unit so that the distance between the top surface of the workpiece and the nozzle of the two-fluid nozzle is a predetermined first distance based on the height of the top surface of the workpiece held on the holding surface of the chuck table measured by the top surface height measuring device. This enables the top surface of the workpiece to be consistently and appropriately cleaned with two fluids. For example, if multiple chuck tables of different heights are arranged on the turntable, the height of the two-fluid nozzle can be adjusted for each chuck table that holds the workpiece by suction. Furthermore, even if grinding is terminated before the workpiece reaches the planned finish grinding thickness, the height of the two-fluid nozzle is adjusted based on the height of the top surface of the workpiece measured by the top surface height measuring device, thereby consistently optimizing the two-fluid cleaning of the workpiece. Furthermore, when the grinding device of the present invention grinds (self-grinds) the holding surface of the chuck table at an appropriate timing during the process of continuously grinding multiple workpieces, for example, even if the height of the holding surface changes before and after self-grinding, the nozzle height adjustment mechanism can be controlled so that the distance between the holding surface and the injection nozzle becomes a preset second distance based on the value measured by the upper surface height measuring device or the holding surface height measuring device, thereby making it possible to properly clean the holding surface with two fluids.

[0009] In the processing apparatus of the present invention, the spinner cleaning mechanism comprises a spinner holding mechanism that holds the workpiece and rotates around the center of the workpiece, a spinner two-fluid nozzle that sprays a mixture of water and air from the spinner nozzle onto the top surface of the workpiece held by the spinner holding mechanism, and a spinner nozzle height adjustment mechanism that adjusts the height of the spinner two-fluid nozzle.The spinner control unit comprises a setting unit that pre-sets a distance suitable for cleaning between the surface to be cleaned and the spinner nozzle, and controls the spinner nozzle height adjustment mechanism so that the distance between the top surface of the workpiece held by the spinner holding mechanism and the spinner nozzle becomes a pre-set third distance based on the value set in the setting unit and the value measured by the thickness measurement unit.By constantly adjusting the distance between the top surface of the workpiece held by the spinner holding mechanism and the spinner nozzle to an appropriate third distance, for example, corresponding to the thickness of the workpiece held on the spinner holding surface after grinding is completed, the top surface of the workpiece can be two-fluid cleaned. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view showing an example of a grinding device. [Figure 2] This is a side view showing the state in which the top surface of the first workpiece having a finishing thickness held on the holding surface of the chuck table is being properly cleaned with the distance between the top surface and each of the nozzles of the first two-fluid nozzle to the third two-fluid nozzle set to a predetermined first distance. [Figure 3] FIG. 3 is a plan view showing an example of an arrangement pattern of first to third two-fluid nozzles. [Figure 4] FIG. 10 is a plan view showing another example of the arrangement pattern of the first to third two-fluid nozzles. [Figure 5] This is a side view showing a state in which the top surface of a second workpiece, which is thicker than the finishing thickness and held on the holding surface of the chuck table, is not properly cleaned because the distance between the top surface and each of the nozzles of the first two-fluid nozzle to the third two-fluid nozzle is shorter than the predetermined first distance. [Figure 6]This is a side view showing a state in which the top surface of a second workpiece held on the holding surface of the chuck table is being properly cleaned with the distance between the top surface of the second workpiece and each of the nozzles of the first two-fluid nozzle to the third two-fluid nozzle set to a predetermined first distance. [Figure 7] This is a side view showing a state in which the top surface of a third workpiece, which is thinner than the finishing thickness and held on the holding surface of the chuck table, is not properly cleaned because the distance between the top surface and each of the nozzles of the first two-fluid nozzle to the third two-fluid nozzle is longer than the predetermined first distance. [Figure 8] This is a side view showing a state in which the top surface of a third workpiece held on the holding surface of the chuck table is being properly cleaned with the distance between the top surface of the third workpiece and each of the nozzles of the first two-fluid nozzle to the third two-fluid nozzle set to a predetermined first distance. [Figure 9] This is a side view showing the state in which the top surface of the first workpiece is being properly cleaned with the distance between the top surface of the first workpiece of finishing thickness held on the holding surface of the chuck table and the injection port of the slit nozzle set to a preset first distance. [Figure 10] This is a side view showing a state in which the top surface of the second workpiece, which is thicker than the finishing thickness and held on the holding surface of the chuck table, is not properly cleaned because the distance between the top surface and the injection port of the slit nozzle is shorter than the preset first distance. [Figure 11] This is a side view showing a state in which the top surface of the third workpiece, which is thinner than the finishing thickness and held on the holding surface of the chuck table, is not properly cleaned because the distance between the top surface and the injection port of the slit nozzle is longer than the preset first distance. [Figure 12] This is a side view showing the state in which the holding surface of the chuck table after self-grinding is properly cleaned with the distance between the holding surface and each of the nozzles of the first to third two-fluid nozzles set to a predetermined second distance. [Figure 13] FIG. 1 is a perspective view showing an example of a processing apparatus equipped with a spinner cleaning mechanism. [Figure 14] 10 is a side view showing a state in which the thickness measuring unit is measuring the thickness of the workpiece after it is held on the chuck table and grinding is completed. FIG. [Figure 15] This is a side view that explains the case where the top surface of a workpiece held on the spinner holding surface of the spinner table is properly cleaned when the distance between the top surface of the workpiece and each of the spinner jet nozzles of the first spinner two-fluid nozzle to the third spinner two-fluid nozzle is set to a preset third distance. DETAILED DESCRIPTION OF THE INVENTION

[0011] 1 is an apparatus that grinds a workpiece 90 held on a chuck table 30 using a grinding mechanism 5. The front (-Y direction side) of a base 10 of the grinding apparatus 1 is a loading / unloading area where the workpiece 90 is loaded and unloaded onto the chuck table 30, and the rear (+Y direction side) of the base 10 is a processing area where the grinding mechanism 5 performs grinding of the workpiece 90 held on the chuck table 30. The grinding device 1 may be configured to have two grinding mechanisms, a rough grinding mechanism and a finish grinding mechanism, and a rotating turntable may be configured so that multiple chuck tables 30, each holding a workpiece 90 and arranged at equal intervals around the periphery of the turntable, can be positioned below each grinding mechanism.

[0012] The workpiece 90 shown in FIG. 1 is, for example, a circular semiconductor wafer made of a silicon base material or the like. A plurality of devices are formed on a surface 900 (lower surface 900) of the workpiece 90 facing downward in FIG. 1, and is protected by a protective tape (not shown). A rear surface 903 (upper surface 903) of the workpiece 90 facing upward becomes the processing surface to be subjected to grinding. Note that the workpiece 90 may be made of gallium arsenide, sapphire, gallium nitride, resin, ceramics, silicon carbide, or the like in addition to silicon, or may be a package substrate, a bonded workpiece, a wafer to be ground to a very thin finishing thickness, or the like.

[0013] The chuck table 30, which has a circular outer shape in a plan view, includes, for example, a circular plate-shaped porous member 300 and a frame 301 that supports the porous member 300. The porous member 300 is connected to a suction source (not shown), such as an ejector mechanism or a vacuum generator, and the suction force generated by the suction source is transmitted to a holding surface 302, which is the upper surface of the porous member 300, allowing the chuck table 30 to suction-hold the workpiece 90 on the holding surface 302.

[0014] As shown in FIG. 1, the chuck table 30 is surrounded by a cover 39, and is rotatable about a rotation axis whose axial direction is the Z-axis direction (vertical direction) and passes through the center of the holding surface 302. The chuck table 30 can be moved back and forth in the Y-axis direction on the base 10 by a Y-axis feed unit (not shown), such as an electric slider, disposed below the cover 39 and a bellows cover 390 connected to the cover 39 and extending and contracting in the Y-axis direction.

[0015] A column 11 is erected on the rear side of the base 10, and a grinding feed unit 17 is arranged on the front surface of the column 11 on the -Y direction side, which moves the grinding mechanism 5 in a vertical direction (Z-axis direction) perpendicular to the holding surface 302 of the chuck table 30. The grinding feed unit 17 is composed of a ball screw 170 whose axial direction is the Z-axis direction, a pair of guide rails 171 extending parallel to the ball screw 170, a motor 172 connected to the ball screw 170 and rotating the ball screw 170, and a lifting plate 173 whose internal nut is threaded onto the ball screw 170 and whose sides slide against the pair of guide rails 171. When the motor 172 rotates the ball screw 170, the lifting plate 173 is guided by the guide rails 171 and moves in the Z-axis direction, and the grinding mechanism 5 attached to the lifting plate 173 also moves in the Z-axis direction.

[0016] The grinding mechanism 5 includes a rotating shaft 50 whose axial direction is in the Z-axis direction, a housing 51 that rotatably supports the rotating shaft 50 by an air bearing or the like formed inside, a motor 52 that rotates the rotating shaft 50, a disk-shaped mount 53 connected to the lower end of the rotating shaft 50, a grinding wheel 54 that is detachably attached to the lower surface of the mount 53, and a holder 55 that supports the housing 51 and is connected to the lifting plate 173.

[0017] The grinding wheel 54 includes a wheel base 542 and a plurality of roughly rectangular parallelepiped segment grinding wheels arranged in a ring shape on the bottom surface of the wheel base 542. The segment grinding wheels are formed by, for example, fixing diamond abrasive grains with a resin bond, a vitrified bond, or the like. The plurality of segment grinding wheels arranged in a ring shape form a ring-shaped grinding wheel 541. It is also possible to arrange a so-called continuous arrangement grinding wheel, in which the segment grinding wheels are arranged in a ring shape with no gaps between them, on the underside of the wheel base 542.

[0018] Inside the rotating shaft 50, a flow path (not shown) that is connected to a grinding water supply source and serves as a passage for grinding water is provided, penetrating the axial direction of the rotating shaft 50, and the flow path (not shown) further passes through the mount 53 and opens at the bottom surface of the wheel base 542 so that grinding water can be sprayed toward the annular grinding wheel 541.

[0019] A thickness measurement unit 38 that measures the thickness of the workpiece 90 during grinding, for example, by contact, is disposed near the grinding wheel 54 that has been lowered to a height at which the workpiece 90 is ground. The thickness measurement unit 38 includes, for example, a pair of measuring devices (height gauges), that is, a holding surface height measuring device 381 that measures the height of the holding surface 302 that is the upper surface of the chuck table 30 (actually, the upper surface of the frame 301 that is flush with the holding surface 302), and an upper surface height measuring device 382 that measures the height of the upper surface 903 of the workpiece 90 that is held by suction on the chuck table 30.

[0020] The holding surface height measuring device 381 and the upper surface height measuring device 382 are each equipped with a contact at its tip that comes into contact with each measurement surface. The contacts of the holding surface height measuring device 381 and the upper surface height measuring device 382 are supported so that they can move up and down, and can be pressed against each measurement surface with an appropriate force. Each measuring surface is equipped with a scale that reads the height of the contact whose tip is in contact with the corresponding measurement surface, and the holding surface height and the upper surface height of the workpiece 90 are measured based on the value on the scale. The thickness measurement unit 38 is equipped with a calculation unit 383 that calculates the difference between the holding surface height measured by the holding surface height measuring device 381 and the top surface height of the workpiece 90 measured by the top surface height measuring device 382.

[0021] A second column 12 is erected in the -X direction region on the base 10 shown in FIG. 1 , and a nozzle height adjustment mechanism 6 is disposed on the +X direction side of the second column 12, which adjusts the heights of the first two-fluid nozzle 71, the second two-fluid nozzle 72, and the third two-fluid nozzle 73, for example, relative to the holding surface 302 of the chuck table 30.

[0022] The nozzle height adjustment mechanism 6 is composed of a ball screw 60 whose axial direction is the Z-axis direction, a guide rail 61 extending parallel to the ball screw 60, a motor 62 connected to the ball screw 60 and rotating the ball screw 60, and a lifting block 63 whose internal nut is threaded onto the ball screw 60 and whose side is in sliding contact with the guide rail 61.When the motor 62 rotates the ball screw 60, the lifting block 63 is guided by the guide rail 61 and moves back and forth in the Z-axis direction, and the first two-fluid nozzle 71 to the third two-fluid nozzle 73 attached to the lifting block 63 also move up and down in the Z-axis direction.

[0023] For example, the nozzle height adjustment mechanism 6 is equipped with a height detection unit 66 that detects the heights of the first to third two-fluid nozzles 71 to 73 from the height of the lifting block 63. The height detection unit 66 is equipped with a scale 660 that extends in the Z-axis direction along the guide rail 61, and a reader 662 that is attached to the lifting block 63, moves up and down together with the lifting block 63 along the scale 660, and optically reads the graduations of the scale 660. The height detection unit 66 may read the heights of the first to third two-fluid nozzles 71 to 73 using an encoder connected to the rotation shaft of the motor 62 instead of the scale 660 .

[0024] As shown in Fig. 1, the grinding apparatus 1 according to the present invention is equipped with a control unit 8 that controls the entire apparatus. The control unit 8 is composed of a CPU that performs calculations according to a control program, a storage medium such as a memory, and the like. The control unit 8 is electrically connected to the grinding feed unit 17, the grinding mechanism 5, and the like via, for example, a wired or wireless communication path. Under the control of the control unit 8, the grinding feed unit 17 moves the grinding mechanism 5 up and down, and the grinding wheel 54 in the grinding mechanism 5 rotates, and the like.

[0025] The control unit 8 is also electrically connected to, for example, the motor 62 of the nozzle height adjustment mechanism 6, and can supply an operating signal to the motor 62 to control the up and down movement of the first two-fluid nozzle 71 to the third two-fluid nozzle 73 by the nozzle height adjustment mechanism 6. In addition, the reader 662 of the height detection section 66 transmits the read height information of the first two-fluid nozzle 71 to the third two-fluid nozzle 73 to the control unit 8.

[0026] 1 is connected to the lower surface of the lifting block 63 via a rod-shaped connecting member 634. A rectangular opening 750 is formed in the lower surface of the box 75, and the movement path of the chuck table 30 is located below the opening 750.

[0027] The grinding apparatus 1 of this embodiment is provided with a plurality of (e.g., three) two-fluid nozzles each having an ejection port for ejecting a mixture of water and air, so as to correspond to a radial area 904 from the center 902 to the outer periphery of the workpiece 90 held on the holding surface 302 of the chuck table 30. Specifically, the first two-fluid nozzle 71 shown in FIG. 1 has its ejection port 710 facing the center 902 of the workpiece 90, which is held by suction on the holding surface 302 of the chuck table 30 with their centers aligned, in the Z-axis direction. A second two-fluid nozzle 72 and a third two-fluid nozzle 73 are also provided radially outwardly of the workpiece 90, spaced evenly apart, so that their ejection ports 720 and 730 face the upper surface 903 of the workpiece 90. For example, as shown in FIG. 2, the ejection port 730 of the third two-fluid nozzle 73 is positioned a predetermined distance toward the center of the workpiece 90 from the outer periphery. That is, as shown in FIG. 3 , the first two-fluid nozzle 71, the second two-fluid nozzle 72, and the third two-fluid nozzle 73 are arranged at equal intervals so as to spray the two-fluid T onto a radial area 904 of the workpiece 90. As shown in FIG. 3 , for example, the circular spray areas of the two-fluid T sprayed downward from the first two-fluid nozzle 71 to the third two-fluid nozzle 73 in a conical spray pattern may slightly overlap when viewed from above and contact the upper surface 903 of the workpiece 90. Note that the overlapping spray areas overlap so that their cleaning powers do not cancel each other out. Note that, although the first two-fluid nozzle 71, the second two-fluid nozzle 72, and the third two-fluid nozzle 73 are arranged in a line in the radial direction of the workpiece 90 in FIG. 3 , they may also be arranged staggered in the circumferential direction as shown in FIG. 4 . 4 , the two-fluid T jetted from the first two-fluid nozzle 71 located closest to the center 902 of the workpiece 90 cleans an annular region including the center 902 of the upper surface 903 of the relatively rotating workpiece 90, the two-fluid T jetted from the third two-fluid nozzle 73 located farthest from the center 902 of the workpiece 90 cleans an annular region including the outer periphery of the upper surface 903 of the rotating workpiece 90, and the two-fluid T jetted from the second two-fluid nozzle 72 cleans an annular region between the annular cleaning region by the first two-fluid nozzle 71 and the annular cleaning region by the third two-fluid nozzle 73, thereby cleaning the entire upper surface 903. Note that the annular regions may overlap slightly.

[0028] The first two-fluid nozzle 71, the second two-fluid nozzle 72, and the third two-fluid nozzle 73 have similar structures, so only the structure of the first two-fluid nozzle 71 will be described below. In this embodiment, the first two-fluid nozzle 71 has a linear outer shape extending in the Z-axis direction and is a flat pattern nozzle in which the two fluids sprayed from the nozzle 710 formed at its bottom spread out in a fan-like flat spray pattern, or a full cone pattern nozzle in which a conical spray pattern is obtained, but the present invention is not limited to these. The spread angle of the two fluids sprayed from the nozzle 710 is recognized in advance by the control unit 8.

[0029] A cleaning water supply source 77, which is made up of a pump or the like and can deliver, for example, pure water as cleaning water, is connected to the upper side of the first two-fluid nozzle 71 via a water pipe 76, such as a joint or the like and a resin tube. Although not shown in FIG. 1, the cleaning water supply source 77 is also connected to the second two-fluid nozzle 72 and the third two-fluid nozzle 73.

[0030] An air supply source 79, which may be a compressor or the like and is capable of delivering compressed air, is connected to the upper side of the first two-fluid nozzle 71 via piping 78, which may be a joint, a resin tube, or the like. Although not shown in FIG. 1, the air supply source 79 is also connected to the second two-fluid nozzle 72 and the third two-fluid nozzle 73.

[0031] The first two-fluid nozzle 71, the second two-fluid nozzle 72, and the third two-fluid nozzle 73 are attached so as to be positioned in the internal space of the box 75, and are arranged at the same height. The box 75 is intended to prevent the two fluids sprayed onto the upper surface 903 of the workpiece 90 from scattering over an unnecessarily wide area when cleaning the workpiece 90 held by suction on the holding surface 302 of the chuck table 30. Note that the grinding apparatus 1 may be configured without the box 75.

[0032] 1, the control unit 8 includes, for example, a first control unit 81, a second control unit 82, and a third control unit 83. Based on the height value of the upper surface 903 of the workpiece 90 held by suction on the holding surface 302 of the chuck table 30 measured by the upper surface height measuring device 382, ​​the first control unit 81 controls the nozzle height adjustment mechanism 6 so that the distances between the upper surface 903 of the workpiece 90 held on the holding surface 302 and the nozzles 710 of the first two-fluid nozzle 71 to 730 of the third two-fluid nozzle 73 become preset first distances.

[0033] The second control unit 82 controls the nozzle height adjustment mechanism 6 based on the height value of the holding surface 302 of the chuck table 30 measured by the top surface height measuring device 382 so that the distance between the holding surface 302 and the nozzle 710 of the first two-fluid nozzle 71 to the nozzle 730 of the third two-fluid nozzle 73 becomes a predetermined second distance.

[0034] The third control unit 83 controls the nozzle height adjustment mechanism 6 based on the height value of the holding surface 302 of the chuck table 30 measured by the holding surface height measuring device 381 so that the distance between the holding surface 302 and the nozzle 710 of the first two-fluid nozzle 71 to the nozzle 730 of the third two-fluid nozzle 73 becomes a predetermined second distance.

[0035] The following describes the operation of the grinding apparatus 1 when grinding a workpiece 90 held on the chuck table 30. First, in the attachment / detachment area, the first workpiece 90 is placed on the holding surface 302 of the chuck table 30 with their centers substantially aligned. A suction force generated by a suction source (not shown) is transmitted to the holding surface 302, and the chuck table 30 holds the workpiece 90 on the holding surface 302 by suction.

[0036] Next, the chuck table 30 holding the workpiece 90 is moved in the +Y direction by a Y-axis feed unit (not shown) to below the grinding mechanism 5. Then, the center of rotation of the grinding wheel 541 of the grinding mechanism 5 is shifted by a predetermined distance in the horizontal direction relative to the center of rotation of the workpiece 90, and the grinding wheel 541 is positioned so that its rotational trajectory passes through the center of rotation 902 of the workpiece 90.

[0037] To start grinding, the motor 52 rotates the grinding wheel 54, the grinding mechanism 5 is lowered by the grinding feed unit 17, and the rotating grinding stone 541 comes into contact with the upper surface 903 of the workpiece 90, thereby performing grinding. During grinding, the chuck table 30 rotates at a predetermined rotational speed, and the workpiece 90 held on the holding surface 302 also rotates, so that the grinding stone 541 grinds the entire upper surface 903 of the workpiece 90. In addition, grinding water passing through a flow path (not shown) is supplied to the contact portion between the grinding stone 541 and the workpiece 90, thereby cooling the contact portion.

[0038] During grinding, the thickness measurement unit 38 measures the height of the holding surface 302 serving as a reference surface (the height of the top surface of the frame 301 on which the workpiece 90 is not placed) using the holding surface height measuring device 381, measures the height of the top surface 903 of the workpiece 90 to be ground using the top surface height measuring device 382, ​​and calculates the difference between the two measurements, thereby sequentially measuring the thickness of the workpiece 90 during grinding. After the workpiece 90 has been ground to the desired thickness (the planned finish thickness), the grinding mechanism 5 rises, and the grinding wheel 541 moves away from the workpiece 90, thereby completing the grinding. Here, in the grinding apparatus 1 according to the present invention, information about the height of the top surface 903 of the workpiece 90 at the end of grinding, measured by the top surface height measuring device 382, ​​is sent to the control unit 8 and stored.

[0039] The chuck table 30, which holds the workpiece 90 by suction after grinding, moves in the -Y direction, and as shown in Figure 2, the nozzle 710 of the first two-fluid nozzle 71 is positioned above the center of rotation 902 of the upper surface 903 of the workpiece 90, and the second two-fluid nozzle 72 and the third two-fluid nozzle 73 are positioned above it along the radial area 904 of the workpiece 90.

[0040] 1 controls the nozzle height adjustment mechanism 6 based on the height Z1 shown in FIG. 2 of the upper surface 903 of the workpiece 90 after grinding that is held on the holding surface 302, which height Z1 is measured by the upper surface height measuring device 382 and stored in a storage medium of the control unit 8. The storage medium of the control unit 8 stores in advance first distances L1 between the upper surface 903 of the workpiece 90 that is held on the holding surface 302 and the nozzles 710 of the first two-fluid nozzle 71 to 730 of the third two-fluid nozzle 73. The first distance L1 is a value that prevents the cleaning powers of the two fluids sprayed from the first two-fluid nozzle 71, the second two-fluid nozzle 72, and the third two-fluid nozzle 73 from canceling each other out in the areas sprayed onto the upper surface 903 of the workpiece 90, and is a distance that allows the upper surface 903 of the workpiece 90 to be properly cleaned by the two fluids sprayed from the first two-fluid nozzle 71 to the third two-fluid nozzle 73. The first distance L1 may be a value that prevents the areas from overlapping. The first distance L1 may be determined by performing a cleaning experiment at different distances, capturing an image of the upper surface 903 of the workpiece 90 after cleaning with a camera, and determining the distance at which no circular or annular stains remain in the captured image.

[0041] 1 reads the heights of the nozzle 710 of the first two-fluid nozzle 71 to the nozzle 730 of the third two-fluid nozzle 73 from the value on the scale 660, and transmits this height information to the first control unit 81. Upon receiving this information, the first control unit 81 adjusts and supplies an operating signal to the motor 62 of the nozzle height adjustment mechanism 6 to rotate it forward or backward, thereby lowering or raising the first two-fluid nozzle 71 to the third two-fluid nozzle 73, so that the nozzle 710 of the first two-fluid nozzle 71 to the nozzle 730 of the third two-fluid nozzle 73 are positioned a first distance L1 above the upper surface 903 of the workpiece 90 held on the holding surface 302, as shown in FIG. For example, by positioning the first two-fluid nozzle 71 to the third two-fluid nozzle 73 at height Z2, the nozzle 710 of the first two-fluid nozzle 71 to the nozzle 730 of the third two-fluid nozzle 73 are positioned a first distance L1 above the upper surface 903 of the workpiece 90 held on the holding surface 302. In addition, an encoder may detect the rotation speed of the motor 62 of the nozzle height adjustment mechanism 6 shown in Figure 1, and the first control unit 81, upon receiving an encoder signal from the encoder, may feedback control the operating signal supplied to the motor 62 to position the first two-fluid nozzle 71 to the third two-fluid nozzle 73 at an appropriate height Z2.

[0042] 2 supplies cleaning water to the first to third bi-fluid nozzles 71 to 73, and high-pressure air is supplied from an air supply source 79 to the first to third bi-fluid nozzles 71 to 73. The cleaning water and air are mixed in the first to third bi-fluid nozzles 71 to 73 to form bi-fluid T, which is then sprayed toward the top surface 903 of the workpiece 90 from the nozzles 710 to 730 of the first to third bi-fluid nozzles 71 to 73. As the chuck table 30 rotates, the entire top surface 903 of the workpiece 90 is cleaned by the bi-fluid T, and fine grinding chips and other deposits adhering to the top surface 903 of the workpiece 90 are washed away. The cleaning water of the two fluids T that has washed away the deposits flows down from above the chuck table 30 and flows into a water case (not shown), for example, through drainage holes formed on the sides of the cover 39 and the bellows cover 390 shown in FIG. 1.

[0043] As shown in Figure 2, in this embodiment, the first two-fluid nozzle 71 to the third two-fluid nozzle 73 are arranged above a radial area 904 from the center 902 to the outer peripheral edge of the workpiece 90, and the nozzle 710 of the first two-fluid nozzle 71 to the nozzle 730 of the third two-fluid nozzle 73 are positioned a first distance L1 above the top surface 903 of the workpiece 90.Therefore, the radial area 904 is properly cleaned without leaving any residue by the two-fluid T sprayed from the nozzle 710 of the first two-fluid nozzle 71 to the nozzle 730 of the third two-fluid nozzle 73 and spread out, for example, in a fan shape.

[0044] After the two-fluid cleaning of the upper surface 903 of the workpiece 90 has been performed for a predetermined time, for example, the supply of cleaning water from the cleaning water supply source 77 is stopped while the supply of air from the air supply source 79 is continued, and the workpiece 90 is dried by the air. Note that the supply of air from the air supply source 79 may also be stopped, and the workpiece 90 may be spin-dried by rotating the chuck table 30.

[0045] Next, the first workpiece 90 that has been ground and cleaned is carried out from the chuck table 30 shown in Figure 1, and a new second workpiece 90 is suction-held on the chuck table 30 in the same manner as the first workpiece 90. Thereafter, the second workpiece 90 is also subjected to grinding in the same manner as the first workpiece 90.

[0046] During grinding of the second workpiece 90 after the thickness measurement by the thickness measurement unit 38 shown in FIG. 1, an abnormal condition such as surface burn may occur on the top surface 903 of the workpiece 90, preventing the second workpiece 90 from being ground to the predetermined thickness, resulting in the second workpiece 90 being thicker than the predetermined finished thickness. In this case, information about the height of the top surface 903 of the second workpiece 90 after grinding measured by the top surface height measuring device 382 (e.g., height Z3 shown in FIG. 5) is sent to and stored in the control unit 8. Note that even if the second workpiece 90 is a wafer of a different type from the first workpiece 90 or if the second workpiece 90 has a thicker originally planned finished thickness than the first workpiece 90, the height Z3 of the top surface 903 of the second workpiece 90 after grinding shown in FIG. 5 will be higher than the height Z1 of the top surface 903 of the first workpiece 90.

[0047] Figure 5 shows a case in which, for example, unlike conventional grinding devices, the heights of the nozzles 710 of the first two-fluid nozzle 71 to the nozzles 730 of the third two-fluid nozzle 73 are not adjusted according to the height value of the upper surface 903 of the workpiece 90, but rather the nozzle height adjustment mechanism 6 positions the nozzles 710 of the first two-fluid nozzle 71 to the nozzles 730 of the third two-fluid nozzle 73 at height Z2 when the first workpiece 90 shown in Figure 2 was cleaned, and the second workpiece 90 is cleaned.

[0048] In this case, the distance from height Z3 of the upper surface 903 of the second workpiece 90 to height Z2 of the nozzles 710 of the first two-fluid nozzle 71 to 730 of the third two-fluid nozzle 73 is shorter than the predetermined appropriate first distance L1 shown in Figure 2.Therefore, as shown in Figure 5, the fan-shaped spread of the two-fluids T sprayed from the nozzles 710 of the first two-fluid nozzle 71 to 730 of the third two-fluid nozzle 73 is insufficient when the two-fluids T reach the radial area 904 of the rotating workpiece 90, resulting in the creation of areas 905 in the radial area 904 where it is difficult for the two-fluids T to reach, and the upper surface 903 of the workpiece 90 is not sufficiently cleaned.

[0049] On the other hand, in the grinding apparatus 1 according to the present invention, the first control unit 81 shown in Fig. 1 controls the nozzle height adjustment mechanism 6 while receiving information on the height Z3 of the upper surface 903 of the workpiece 90 after grinding, measured by the upper surface height measuring device 382, ​​and information sent from the reader 662 of the height detection unit 66 shown in Fig. 1. The nozzle height adjustment mechanism 6 then raises the first to third two-fluid nozzles 71 to 73, and positions the first to third two-fluid nozzles 71 to 73 at, for example, height Z4 shown in Fig. 6, whereby the ejection ports 710 of the first to third two-fluid nozzles 71 to 730 are positioned a first distance L1 above the upper surface 903 of the second workpiece 90 held on the holding surface 302.

[0050] In this state, while the chuck table 30 rotates, the two-fluid T is sprayed from the nozzles 710 of the first two-fluid nozzle 71 to the nozzles 730 of the third two-fluid nozzle 73 and spreads out, for example, in a fan shape, to thoroughly and properly clean the radial area 904 of the upper surface 903 of the second workpiece 90, and fine grinding debris and the like adhering to the entire upper surface 903 is properly washed away.

[0051] Next, the second workpiece 90, which has been cleaned and dried, is removed from the chuck table 30, and a new third workpiece 90 is suction-held to the chuck table 30 in the same manner as the first and second workpieces 90, and the third workpiece 90 is ground.

[0052] For example, a thickness thinner than the set thickness set for the first workpiece 90 is set for the third workpiece 90. In this state, thickness measurement is performed by the thickness measurement unit 38 shown in FIG. 1 during grinding. As a result, the ground third workpiece 90 is ground thinner than the first workpiece 90. In this case, information about the height of the top surface 903 of the third workpiece 90 at the end of grinding measured by the top surface height measuring device 382 (for example, height Z5 shown in FIG. 7) is sent to the control unit 8 and stored.

[0053] Figure 7 assumes a case in which, for example, unlike conventional grinding devices, the heights of the nozzles 710 of the first two-fluid nozzle 71 to the nozzles 730 of the third two-fluid nozzle 73 are not adjusted according to the height value of the upper surface 903 of the workpiece 90, but rather the nozzle height adjustment mechanism 6 shown in Figure 1 positions the nozzles 710 of the first two-fluid nozzle 71 to the nozzles 730 of the third two-fluid nozzle 73 at height Z2 when the first workpiece 90 was cleaned, and the third workpiece 90 is cleaned.

[0054] Because the distance from height Z5 of the top surface 903 of the third workpiece 90 to height Z2 of the nozzles 710 of the first two-fluid nozzle 71 to 730 of the third two-fluid nozzle 73 is longer than a predetermined appropriate first distance L1 (see FIG. 2 ), the two fluids T sprayed from the nozzles 710 of the first two-fluid nozzle 71 to 730 of the third two-fluid nozzle 73 spread out too far in a fan shape, causing the two fluids T to collide and interfere with each other in the air before reaching a radial area 904 of the rotating workpiece 90. As a result, a location 906 is created in the radial area 904 where it is difficult for the two fluids T to reach, resulting in insufficient cleaning of the top surface 903 of the workpiece 90.

[0055] On the other hand, in the grinding apparatus 1 according to the present invention, the first control unit 81 shown in Fig. 1 controls the nozzle height adjustment mechanism 6 while receiving information on the height Z5 of the upper surface 903 of the workpiece 90 after grinding, measured by the upper surface height measuring device 382, ​​and information sent from the reader 662 shown in Fig. 1. Then, the nozzle height adjustment mechanism 6 lowers the first to third two-fluid nozzles 71 to 73 as shown in Fig. 8, and positions the first to third two-fluid nozzles 71 to 73 at height Z6, for example, so that the ejection ports 710 of the first to third two-fluid nozzles 71 to 73 are positioned a first distance L1 above the upper surface 903 of the third workpiece 90 held on the holding surface 302.

[0056] In this state, the chuck table 30 rotates, and the two-fluid T sprayed from the nozzle 710 of the first two-fluid nozzle 71 to the nozzle 730 of the third two-fluid nozzle 73 and spreading out in a fan shape thoroughly and properly cleans the radial area 904 of the top surface 903 of the third workpiece 90, properly washing away any fine grinding chips and other adhesions adhering to the entire top surface 903.

[0057] The two-fluid nozzles provided in the grinding apparatus 1 are not limited to the first two-fluid nozzle 71 to the third two-fluid nozzle 73 shown in Fig. 1 and Fig. 2. For example, as shown in Fig. 9, a rectangular slit nozzle 70 may be disposed above the movement path of the chuck table 30 shown in Fig. 1 so as to be movable up and down by a nozzle height adjustment mechanism 6.

[0058] 9 extends in the X-axis direction with a length equal to or greater than the radial area 904 of the workpiece 90, and has a slit-shaped injection port 700 formed in its lower surface. A cleaning water supply source 77 and an air supply source 79 are connected to the slit nozzle 70.

[0059] Below, we will explain the case where, in a process similar to that described above when cleaning the top surfaces 903 of the first to third workpieces 90, the slit nozzle 70 shown in Figure 9 is used instead of the first two-fluid nozzle 71 to the third two-fluid nozzle 73 shown in Figures 1 and 2.

[0060] The first control unit 81, which receives information about the height of the slit nozzle 70 from the height detection unit 66 shown in FIG. 1, controls the nozzle height adjustment mechanism 6 to lower or raise the slit nozzle 70 so that the injection port 700 of the slit nozzle 70 is positioned a predetermined first distance L1 above the upper surface 903 of the workpiece 90 at height Z1 held on the holding surface 302 of the chuck table 30, as shown in FIG. 9.

[0061] With the nozzle 700 of the slit nozzle 70 positioned at a height Z2 a first distance L1 above the top surface 903 of the workpiece 90 held on the holding surface 302, two fluids T are sprayed in a band from the nozzle 700 of the slit nozzle 70 toward the top surface 903 of the workpiece 90, and the entire top surface 903 of the rotating workpiece 90 is cleaned with the two fluids, properly washing away grinding debris and the like.

[0062] The second workpiece 90 after grinding shown in Fig. 10 is thicker than the planned finish thickness, and the height of the top surface 903 of the second workpiece 90 at the end of grinding, measured by the top surface height measuring device 382 shown in Fig. 1, is height Z3, which is higher than height Z1 of the top surface 903 of the first workpiece 90. Fig. 10 also illustrates a case in which the nozzle height adjustment mechanism 6 shown in Fig. 1 positions the injection port 700 of the slit nozzle 70 at height Z2 when the first workpiece 90 was washed, without adjusting the height of the injection port 700 of the slit nozzle 70 according to the height value of the top surface 903 of the workpiece 90 as in a conventional grinding device, for example.

[0063] In this case, the distance from height Z3 of the upper surface 903 of the second workpiece 90 to height Z2 of the jetting port 700 of the slit nozzle 70 is shorter than the predetermined appropriate first distance L1 shown in Fig. 9, so the band-like two-fluid T jetted from the jetting port 700 reaches the radial area 904 of the rotating workpiece 90 with a force stronger than appropriate, resulting in the generation of locations in the radial area 904 where the two-fluid T bounces off the upper surface 903. As a result, the upper surface 903 of the workpiece 90 is not sufficiently cleaned.

[0064] To prevent such inappropriate cleaning from occurring, in the grinding apparatus 1 of the present invention, the first control unit 81 shown in FIG. 1 receives information on the height Z3 of the upper surface 903 of the workpiece 90 after grinding measured by the upper surface height measuring device 382 and information sent from the reader 662 of the height detection unit 66 shown in FIG. 1, and controls the nozzle height adjustment mechanism 6 to raise the slit nozzle 70 shown in FIG. 10 from the state shown in the figure to position it at height Z4, and then sets the distance between the upper surface 903 of the second workpiece 90 held on the holding surface 302 and the injection port 700 of the slit nozzle 70 to a predetermined first distance L1, and then properly performs two-fluid cleaning of the upper surface 903 of the workpiece 90.

[0065] The third workpiece 90 after grinding shown in Fig. 11 is thinner than the planned finish thickness, and the height of the top surface 903 of the third workpiece 90 at the end of grinding, measured by the top surface height measuring device 382 shown in Fig. 1, is height Z5, which is lower than height Z1 of the top surface 903 of the first workpiece 90 shown in Fig. 9. Fig. 11 also illustrates a case where the nozzle height adjustment mechanism 6 positions the injection port 700 of the slit nozzle 70 at height Z2 when the first workpiece 90 shown in Fig. 9 was washed, without adjusting the height of the injection port 700 of the slit nozzle 70 according to the height value of the top surface 903 of the workpiece 90 as in a conventional grinding device, for example.

[0066] In this case, the distance from height Z5 of the top surface 903 of the third workpiece 90 to height Z2 of the nozzle 700 of the slit nozzle 70 is longer than the predetermined appropriate first distance L1, so the band-like two-fluid T sprayed from the nozzle 700 reaches the radial area 904 of the workpiece 90, which is rotating with a force weaker than the appropriate force, resulting in insufficient cleaning of the top surface 903 of the workpiece 90.

[0067] To prevent such inappropriate cleaning from occurring, in the grinding apparatus 1 of the present invention, the first control unit 81 shown in FIG. 1 receives information on the height Z3 of the upper surface 903 of the workpiece 90 after grinding measured by the upper surface height measuring device 382 and information sent from the reader 662 of the height detection unit 66 shown in FIG. 1, and controls the nozzle height adjustment mechanism 6 to lower the slit nozzle 70 shown in FIG. 11 from the state shown in the figure to position it at height Z6, and then sets the distance between the upper surface 903 of the third workpiece 90 held on the holding surface 302 and the injection port 700 of the slit nozzle 70 to a predetermined first distance L1, and then properly performs two-fluid cleaning of the upper surface 903 of the workpiece 90.

[0068] For example, when the grinding process described above is performed successively on a plurality of workpieces 90 one by one, grinding debris may adhere to the holding surface 302 of the chuck table 30 shown in FIG. 1, resulting in poor grinding of the workpieces 90. To address this issue, self-grinding is performed by grinding the holding surface 302 with a grinding wheel 541 to make the holding surface 302 parallel to the underside of the grinding wheel 541, thereby optimizing the condition for grinding the workpieces 90 to a uniform thickness. Note that before performing self-grinding, the grinding wheel 54 used to grind the workpieces 90 may be removed and replaced with another grinding wheel suitable for grinding the holding surface 302.

[0069] Specifically, self-grinding is performed at an appropriate timing after grinding of a certain workpiece 90 is completed and before the next new workpiece 90 is suction-held by the chuck table 30. The chuck table 30, which is not holding the workpiece 90, moves to below the grinding mechanism 5, and the center of rotation of the grinding wheel 541 is shifted a predetermined distance in the horizontal direction relative to the center of rotation of the workpiece 90, and the grinding wheel 541 is positioned so that its rotational path passes through the center of rotation of the chuck table 30.

[0070] The grinding wheel 541, which rotates and descends, comes into contact with the holding surface 302 of the rotating chuck table 30, and grinds the entire surface of the holding surface 302. Grinding water passing through a flow path (not shown) is supplied to the contact area between the grinding wheel 541 and the holding surface 302 to cool the contact area. During self-grinding, the height of the holding surface 302 is measured, for example, by the upper surface height measuring device 382 or the holding surface height measuring device 381 shown in FIG. 1. After self-grinding is performed for a predetermined time and the holding surface 302 is adjusted to an optimal state, the grinding wheel 541 is separated from the holding surface 302.

[0071] In the grinding apparatus 1 according to the present invention, information about the height Z7 of the holding surface 302 shown in Fig. 12 at the end of self-grinding measured by the upper surface height measuring device 382, ​​or information about the height Z7 of the holding surface 302 at the end of self-grinding measured by the holding surface height measuring device 381, is sent to and stored in the control unit 8. The measured value of the upper surface height measuring device 382 and the measured value of the holding surface height measuring device 381 are the same, and the height Z7 of the holding surface 302 after self-grinding is lower than the height of the holding surface 302 before self-grinding.

[0072] Next, the self-ground chuck table 30 moves in the -Y direction, and as shown in Figure 12, the nozzle 710 of the first two-fluid nozzle 71 is positioned above the center of rotation of the holding surface 302 of the chuck table 30, and the second two-fluid nozzle 72 and the third two-fluid nozzle 73 are positioned above it along the radius of the holding surface 302.

[0073] 1 to the control unit 8, the second control unit 82 of the control unit 8 controls the nozzle height adjustment mechanism 6. Alternatively, when measurement information is sent from the holding surface height measurement device 381 of the control unit 8 to the control unit 8, the third control unit 83 of the control unit 8 controls the nozzle height adjustment mechanism 6.

[0074] 12 between the holding surface 302 and the nozzle 710 of the first two-fluid nozzle 71 to the nozzle 730 of the third two-fluid nozzle 73 is stored in advance in the storage medium of the control unit 8. The second distance L2 is a value selected experimentally, empirically, or theoretically, and is a distance at which the holding surface 302 can be appropriately cleaned by the two fluids sprayed from the first two-fluid nozzle 71 to the third two-fluid nozzle 73. Note that the second distance L2 may be the same value as the first distance L1.

[0075] 1 measures the heights of the nozzle 710 of the first two-fluid nozzle 71 to the nozzle 730 of the third two-fluid nozzle 73, and transmits information about the heights to the second control unit 82 or the third control unit 83. Upon receiving this information, the second control unit 82 or the third control unit 83 controls the nozzle height adjustment mechanism 6 to lower and position the first two-fluid nozzle 71 to the third two-fluid nozzle 73 so that the nozzle 710 of the first two-fluid nozzle 71 to the nozzle 730 of the third two-fluid nozzle 73 are positioned at height Z8, a second distance L2 above the holding surface 302.

[0076] With the above positioning performed, the two fluids T are sprayed toward the holding surface 302 from the spray nozzle 710 of the first two fluid nozzle 71 to the spray nozzle 730 of the third two fluid nozzle 73. Then, the entire surface of the rotating holding surface 302 is properly cleaned by the two fluids T. After the two-fluid cleaning of the holding surface 302 is performed for a predetermined time, the spraying of the two fluids T onto the holding surface 302 is stopped, and the holding surface 302 is air-dried or spin-dried.

[0077] It goes without saying that the grinding device 1 according to the present invention is not limited to the above embodiment and may be embodied in various different forms within the scope of its technical concept. Furthermore, the configuration of each part of the grinding device 1 shown in the accompanying drawings, the cleaning process for the upper surface 903 of the workpiece 90, and the cleaning process for the holding surface 302 after self-grinding are not limited to those shown in the accompanying drawings and may be modified as appropriate within the scope of the effects of the present invention.

[0078] 13 shows an example of a processing device 19 equipped with a spinner cleaning mechanism 2. The processing device 19 is, for example, a fully automatic grinding device 19, and parts configured in the same manner as the grinding device 1 in FIG. 1 are assigned the same reference numerals as in FIG. 1.

[0079] The front (-Y direction side) of the base 190 of the grinding device 19 is a loading / unloading area where the workpiece 90 is loaded and unloaded onto the chuck table 30, and the rear (+Y direction side) of the base 190 is a processing area where grinding processing of the workpiece 90 held on the chuck table 30 is performed by the grinding mechanism 5, which is a processing mechanism.

[0080] A first cassette stage 150 and a second cassette stage 151 are provided on the front side (-Y direction side) of the base 190, and a first cassette 157 is placed on the first cassette stage 150, in which a plurality of unprocessed workpieces 90 are stored in a shelf-like manner, and a second cassette 158 is placed on the second cassette stage 151, in which a plurality of processed workpieces 90 are stored in a shelf-like manner.

[0081] A robot 154 is disposed behind the opening on the +Y side of the first cassette 157, which transports the workpiece 90 before processing from the first cassette 157 and transports the workpiece 90 after processing into the second cassette 158.

[0082] A temporary placement area 152 is provided adjacent to the robot 154, and an alignment unit 153 is disposed in the temporary placement area 152. The alignment unit 153 aligns (centers) the unprocessed workpiece 90, which has been carried out from the first cassette 157 and placed in the temporary placement area 152, at a predetermined position using a diameter-reducing alignment pin.

[0083] 13, a carry-in arm 161 configured with a suction pad or the like is disposed near the temporary placement area 152 and carries the workpiece 90 onto the chuck table 30. Next to the carry-in arm 161 is disposed a transport mechanism 162, which is an unloading arm that carries the workpiece 90 out of the chuck table 30 and transports the workpiece 90 to the spinner cleaning mechanism 13. The transport mechanism 162 holds the workpiece 90 by suction with a suction pad and is capable of rotating and moving the workpiece 90 within a horizontal plane.

[0084] 1, a single-wafer type spinner cleaning mechanism 2 is disposed in the vicinity of the transport mechanism 162, which cleans the upper surface 903 of the processed workpiece 90 transported by the transport mechanism 162. The spinner cleaning mechanism 2, which cleans the upper surface 903 of the workpiece 90 ground by the grinding wheel 54, includes a spinner holding mechanism 20 that holds the workpiece 90 and rotates around a center 902 of the workpiece 90, a spinner two-fluid nozzle that sprays a two-fluid mixture of water and air from a spinner spray nozzle onto the upper surface 903 of the workpiece 90 held by the spinner holding mechanism 20, and a spinner nozzle height adjustment mechanism 22 that adjusts the height of the spinner two-fluid nozzle. The workpiece 90 cleaned and dried by the spinner cleaning mechanism 2 is carried into a second cassette 158 by the robot 154 .

[0085] For example, the spinner two-fluid nozzles are a first spinner two-fluid nozzle 211, a second spinner two-fluid nozzle 212, and a third spinner two-fluid nozzle 213, and have the same structure as the first two-fluid nozzle 71 to the third two-fluid nozzle 73 previously described using Figure 1.

[0086] Spinner holding mechanism 20 is capable of suction-holding workpiece 90 on a spinner table 201 having a flat spinner holding surface 200 made of a porous material or the like. Also, a rotary shaft 202 whose axial direction is the Z-axis and which can be rotated by a spinner motor 203 (see FIG. 15) is connected to the underside of spinner table 201. Spinner table 201 may be an edge-clamp type spinner table that can clamp the annular frame when workpiece 90 is supported by the annular frame.

[0087] Spinner nozzle height adjustment mechanism 22, which is disposed on column 193 erected to the side of spinner holding mechanism 20 shown in Fig. 13, has a structure similar to that of nozzle height adjustment mechanism 6 described above with reference to Fig. 1. That is, when motor 222 rotates ball screw 220, lifting block 223 is accordingly guided by guide rail 221 and moves back and forth in the Z-axis direction, and first spinner bi-fluid nozzle 211 to third spinner bi-fluid nozzle 213 housed in box 225 attached to lifting block 223 via connecting member 224 also move up and down in the Z-axis direction.

[0088] For example, spinner nozzle height adjustment mechanism 22 includes height detection unit 24 having reader 242 that optically reads the graduations of scale 240 extending in the Z-axis direction. Height detection unit 24 may read the heights of first spinner two-fluid nozzle 211 to third spinner two-fluid nozzle 213 using encoder 227 connected to the rotating shaft of motor 222 instead of scale 240.

[0089] The third spinner two-fluid nozzle 213 shown in Figure 13 is arranged so that its spinner injection port 216 faces the center 902 of the workpiece 90, which is held by suction on the spinner holding surface 200 of the spinner table 201 with their centers aligned, in the Z-axis direction, and the second spinner two-fluid nozzle 212 and the first spinner two-fluid nozzle 211 are arranged at equal intervals radially outside the workpiece 90 so that their respective spinner injection ports 215 and spinner injection ports 214 face the upper surface 903 of the workpiece 90.

[0090] A cleaning water supply source 77 is connected to the upper sides of the first spinner two-fluid nozzle 211 to the third spinner two-fluid nozzle 213 via a water pipe 76. In addition, an air supply source 79 is connected to the upper sides of the first spinner two-fluid nozzle 211 to the third spinner two-fluid nozzle 213 via a pipe 78.

[0091] For example, the control unit 8 that controls the entire apparatus includes a spinner control unit 84. The spinner control unit 84 is provided with a setting unit 840 that sets in advance distances (for example, distance L11 shown in FIG. 15) suitable for cleaning between the surface to be cleaned and the spinner jet nozzle 214 of the first spinner two-fluid nozzle 211 to the spinner jet nozzle 216 of the third spinner two-fluid nozzle 213.

[0092] 13, the chuck table 30 can be moved back and forth in the Y-axis direction on the base 190 by a table feed mechanism 37 disposed below the chuck table 30. When a motor 372 rotates a ball screw 370, the table feed mechanism 37 causes a movable plate 373 to move linearly in the Y-axis direction while being guided by a guide rail 371, thereby allowing the chuck table 30 disposed on the movable plate 373 via a table rotation mechanism to move linearly in the Y-axis direction.

[0093] The processing mechanism 5 shown in Figure 13 is equipped with a grinding wheel 54 as a processing tool and processes the upper surface 903 of the workpiece 90 held on the holding surface 302 of the chuck table 30 to reduce its thickness, and is similar to the grinding mechanism 5 shown in Figure 1. The processing mechanism 5 may be a polishing mechanism equipped with a polishing pad as a processing tool, or a cutting tool mechanism equipped with a cutting tool as a processing tool.

[0094] In addition, as shown in Figure 13, the grinding device 19 is also equipped with a first two-fluid nozzle 71 to a third two-fluid nozzle 73, and similar to the grinding device 1 shown in Figure 1, it is also possible to perform two-fluid cleaning of the upper surface 903 of the workpiece 90 held by suction on the holding surface 302 of the chuck table 30.

[0095] 13, the operation of the grinding apparatus 19 when grinding the workpiece 90 held on the chuck table 30 will be described below. First, the robot 154 pulls out the workpiece 90 from the first cassette 157 and moves the workpiece 90 to the temporary placement area 152. Next, the alignment unit 153 centers the workpiece 90 on the temporary placement area 152. Note that a protective tape 92 is attached to the underside 900 of the workpiece 90.

[0096] The carry-in arm 161 holds the upper surface 903 of the workpiece 90 by suction and transports it onto the chuck table 30, and aligns it so that the holding surface 302 of the chuck table 30 and the center of the workpiece 90 approximately coincide with each other. Then, the workpiece 90 is held by the chuck table 30 by suction.

[0097] Thereafter, the workpiece 90 is ground by the grinding mechanism 5. During grinding, the thickness measurement unit 38 shown in FIG. 14 measures the height of the holding surface 302 serving as a reference surface (the height of the upper surface of the frame 301 on which the workpiece 90 is not placed) using the holding surface height measurer 381, measures the height of the upper surface 903 of the workpiece 90 using the upper surface height measurer 382, ​​and calculates the difference between the two measured values ​​using the calculation unit 383, thereby sequentially measuring the thickness of the workpiece 90 during grinding. Then, after the workpiece 90 has been ground to the desired thickness, the grinding mechanism 5 shown in FIG. 13 rises, and the grinding wheel 541 moves away from the workpiece 90, completing the grinding. Here, in the grinding device 19 according to the present invention, information on the thickness value of the workpiece 90 at the end of grinding measured by the thickness measurement unit 38 (in this embodiment, this is a thickness value including the thickness of the protective tape 92, for example, thickness value L10 shown in Figure 14) is sent to the spinner control unit 84 of the control unit 8 and stored.

[0098] 13, which holds the workpiece 90 by suction after grinding, is moved in the -Y direction and positioned near the transfer mechanism 162. Then, the workpiece 90 held by suction by the transfer mechanism 162 is transferred to the spinner cleaning mechanism 2. The workpiece 90 is held by suction on the spinner table 201 with their centers substantially aligned, and the transport mechanism 162 is removed from the workpiece 90 .

[0099] 15 by dashed lines are set to the origin height Z12 through cleaning experiments. The distance between the spinner holding surface 200, which is the surface to be cleaned before the workpiece 90 is suction-held, and the spinner jet nozzle 214 of the first spinner two-fluid nozzle 211 through the spinner jet nozzle 216 of the third spinner two-fluid nozzle 213 is set in the setting unit 840 to a distance (e.g., distance L11) suitable for cleaning the spinner holding surface 200. In this way, the distance between the spinner holding surface 200 and the spinner ejection nozzle 214 of the first spinner two-fluid nozzle 211 to the spinner ejection nozzle 216 of the third spinner two-fluid nozzle 213 may be set to distance L11, and the spinner holding surface 200 that is not holding the workpiece 90 may be cleaned.

[0100] 15, when the ground workpiece 90 is sucked and held on the spinner holding surface 200, the surface to be cleaned by the spinner bi-fluid nozzles 211 to 213 is switched from the spinner holding surface 200 to the top surface 903 of the workpiece 90. Then, the spinner control unit 84 controls the spinner nozzle height adjustment mechanism 22 so that the distance between the top surface 903 of the workpiece 90 held on the spinner table 201 and the spinner jet nozzles 214 to 216 of the third spinner bi-fluid nozzle 211 to 213 becomes the preset third distance L13, based on the distance L11 set in the setting unit 840 and the thickness value L10 of the ground workpiece 90 measured by the thickness measurement unit 38. In this embodiment, the third distance L13 is the same as the distance L11.

[0101] In this embodiment, the distance L11 set in the setting unit 840 is the same as the third distance L13, so that the spinner nozzle height adjustment mechanism 22 specifically controls the spinner nozzle nozzles 214 to 216 of the first spinner bi-fluid nozzle 211 to the third spinner bi-fluid nozzle 213, which are at the origin height Z12 immediately after the workpiece 90 is sucked and held on the spinner table 201, by the thickness value L10 of the workpiece 90. For example, an operation signal is supplied to the motor 222 from the spinner control unit 84, which is electrically connected to the motor 222 of the spinner nozzle height adjustment mechanism 22 and also functions as a servo amplifier, via a wired or wireless communication path, and the rotation speed of the motor 222 detected by the encoder 227 is output as an encoder signal to the input interface of the spinner control unit 84. Then, the spinner control unit 84, which receives the rotation speed of the motor 222 as an encoder signal, performs feedback control to accurately control the lift distance of the first spinner two-fluid nozzle 211 to the third spinner two-fluid nozzle 213, and positions the spinner nozzle 214 of the first spinner two-fluid nozzle 211 to the spinner nozzle 216 of the third spinner two-fluid nozzle 213, which were at the origin height Z12, at a height Z13 which is a third distance L13 (the same distance as distance L11 in this embodiment) suitable for two-fluid cleaning of the upper surface 903 of the workpiece 90. The spinner nozzle height adjusting mechanism 22 may be controlled using height detection information from the height detector 24 shown in FIG.

[0102] With the workpiece 90 positioned as described above, the two fluids are sprayed toward the top surface 903 of the workpiece 90 from the spinner jet nozzle 214 of the first spinner two-fluid nozzle 211 to the spinner jet nozzle 216 of the third spinner two-fluid nozzle 213. Then, the entire top surface 903 of the rotating workpiece 90 is properly cleaned by the two fluids. After the two-fluid cleaning has been performed for a predetermined time, the workpiece 90 is dried by spraying only air from at least the spinner nozzle 216 of the third spinner two-fluid nozzle 213 out of the spinner nozzle 214 of the first spinner two-fluid nozzle 211 to the spinner nozzle 216 of the third spinner two-fluid nozzle 213, or spin drying is performed by rotating the spinner table 201 at a higher speed than during cleaning, and then the robot 154 shown in Figure 13 removes the workpiece 90 after the two-fluid cleaning from the spinner cleaning mechanism 2 and places it in the second cassette 158. [Explanation of symbols]

[0103] 1: Grinding device 10: Base 11: Column 17: Grinding feed unit 170: Ball screw 172: Motor 30: Chuck table 300: Porous member 301: Frame 302: Holding surface 38: Thickness measurement unit 381: Holding surface height measuring device 382: Upper surface height measuring device 383: Calculation unit 39: Cover 390: Bellows cover 5: Grinding mechanism 50: Rotating shaft 54: Grinding wheel 541: Grinding stone 6: Nozzle height adjustment mechanism 60: Ball screw 61: Guide rail 62: Motor 63: Lifting block 634: Connecting member 66: Height detector 660: Scale 662: Reader 70: Slit nozzle 700: Injection nozzle 71: First two-fluid nozzle 710: Jet nozzle 72: Second two-fluid nozzle 720: Injection port 73: Third two-fluid nozzle 730: Injection port 75: Box 750: Opening 76: Water piping 77: Cleaning water supply source 78: Air piping 79: Air supply source 8: Control unit 81: First control section 82: Second control section 83: Third control section 19: Processing device (grinding device) equipped with spinner cleaning mechanism 190: Base 193: Column 152: Temporary placement area 153: Alignment unit 154: Robot 157: First cassette 158: Second cassette 161: Loading arm 162: Transfer mechanism 2: Spinner cleaning mechanism 20: Spinner holding mechanism 200: Spinner holding surface 201: Spinner table 211: First spinner two-fluid nozzle 214: Spinner jet nozzle 212: Second spinner two-fluid nozzle 215: Spinner jet nozzle 213: Third spinner two-fluid nozzle 216: Spinner jet nozzle 22: Spinner nozzle height adjustment mechanism 220: Ball screw 221: Guide rail 222: Motor 223: Lifting block 224: Connecting member 225: Box 227: Encoder 24: Height detection unit 84: Spinner control unit 840: Setting unit 90: Workpiece 903: Upper surface of workpiece 900: Lower surface of workpiece 92: Protective tape

Claims

[Claim 1] a chuck table that holds a workpiece on a holding surface; a processing mechanism that has a processing tool and processes the upper surface of the workpiece held on the holding surface to reduce its thickness; and a thickness measurement unit that measures the thickness of the workpiece held on the holding surface. a spinner cleaning mechanism that cleans an upper surface of a workpiece that has been machined by the processing tool; a transport mechanism that transports the workpiece from the chuck table to the spinner cleaning mechanism; and a spinner control unit, the thickness measurement unit includes an upper surface height measuring device that measures the height of the upper surface of the workpiece held on the holding surface, a holding surface height measuring device that measures the height of the holding surface, and a calculation unit that calculates the difference between the value of the upper surface height measuring device and the value of the holding surface height measuring device as the thickness of the workpiece; The spinner cleaning mechanism includes a spinner holding mechanism that holds a workpiece and rotates around the center of the workpiece, a spinner two-fluid nozzle that injects two fluids, which are a mixture of water and air, from a spinner injection port onto the upper surface of the workpiece held by the spinner holding mechanism, and a spinner nozzle height adjustment mechanism that adjusts the height of the spinner two-fluid nozzle, The spinner control unit is equipped with a setting unit that presets a distance suitable for cleaning between the surface to be cleaned and the spinner nozzle, and controls the spinner nozzle height adjustment mechanism based on the value set in the setting unit and the value measured by the thickness measurement unit so that the distance between the top surface of the workpiece held in the spinner holding mechanism and the spinner nozzle becomes the preset distance, thereby cleaning the top surface of the workpiece held in the spinner holding mechanism.

Images