JP2023104215A - Grinding device - Google Patents

Abstract

To provide a grinding device, which is configured so that ground chips are ejected from a holding surface and porous members constituting the holding surface, without being enlarged in size.SOLUTION: Ground chips intruding from a holding surface 22 into a porous member 21 can be ejected from the porous member 21 and the holding surface 22, by flowing binary fluid 200 from below the porous member 21 toward the holding surface 22, with the holding surface 22 covered with a wafer 100. In order to eject the ground chips from the porous member 21, the wafer 100 which is a work-piece and a carry-out mechanism 172 which is an existing structure are used. This can reduce structures that are added to eject the ground chips from the porous member 21 and from the holding surface 22, which can execute ejection of the ground chips, while avoiding a grinding device 1 from being enlarged in size.SELECTED DRAWING: Figure 3

Description

The present invention relates to grinding equipment.

In the grinding apparatus, the plate-like object sucked and held by the holding surface of the porous member of the chuck table is ground with a grinding wheel, and grinding dust is discharged. Therefore, the holding surface sucks the grinding dust from the outer peripheral portion of the plate-shaped object held by suction. Also, the sucked grinding dust is sucked at the outer peripheral portion of the holding surface and remains on the outer peripheral portion of the holding surface to reduce the suction force of the outer peripheral portion of the holding surface and reduce the thickness of the outer peripheral portion of the plate-like object.

In order to prevent such a reduction in the suction force of the holding surface, self-grinding of the holding surface is periodically performed to remove grinding dust from the outer peripheral portion of the holding surface. However, grinding dust generated when the holding surface is ground by self-grinding enters the porous member, and after self-grinding, grinding dust is left between the lower surface of the plate-like object held by the holding surface and the holding surface. may intervene. As a result, the thickness of the plate may be partially reduced, or cross-shaped cracks may occur in the plate.

Therefore, in the technique disclosed in Patent Document 1, a cover having an area covering the holding surface is provided. Grinding debris is removed from the porous member that constitutes the

JP 2015-060922 A

However, the technique disclosed in Patent Document 1 requires a cover that covers the holding surface and a moving mechanism that moves the cover, which makes the device large.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to discharge grinding dust from a holding surface and a porous member that constitutes the holding surface without increasing the size of the apparatus so that the grinding dust is interposed between the holding surface and the lower surface of the plate-like object. To grind a plate-like object to have a uniform thickness by suppressing it from being broken.

A grinding apparatus (this grinding apparatus) of the present invention comprises a chuck table for sucking and holding a plate-like object by a holding surface of a porous member; a grinding mechanism for grinding the plate-like object sucked and held by the holding surface with a grinding wheel; A grinding apparatus comprising: a carry-in mechanism for holding a plate-shaped object and carrying it into the holding surface; a carry-out mechanism for holding a plate-shaped object and carrying it out from the holding surface; holding the plate-shaped object on the surface by suction, holding the plate-shaped object sucked and held by the holding surface by the carry-out mechanism or the carry-in mechanism, and holding the plate-shaped object in a state covered by the plate-shaped object. Ejecting two fluids, which are a mixture of water and air, from the holding surface, and the two fluids ejected from the holding surface flow between the holding surface and the plate-shaped object. It flows diametrically outward and removes debris from the porous member and the retaining surface.
The grinding apparatus may further include a bottom surface cleaning mechanism that cleans the bottom surface of the plate-shaped object held by the carry-out mechanism or the carry-in mechanism, and the control unit ejects the two fluids from the holding surface. , the lower surface of the plate-shaped object separated from the holding surface is washed by the lower surface washing mechanism, the holding surface is covered with the plate-shaped object again, the two fluids are ejected from the holding surface, and the porous Grinding debris may be removed from the member and the retaining surface.

In this grinding apparatus, the two fluids are caused to flow through the porous member while the holding surface is covered with the plate-shaped object, so that the grinding dust entering the porous member from the holding surface can be discharged from the porous member and the holding surface. . Therefore, it is possible to suppress the presence of grinding dust between the holding surface and the workpiece during grinding by the grinding mechanism, so that the workpiece can be ground to have a uniform thickness.

In addition, in this grinding apparatus, a carry-out mechanism or a carry-in mechanism having an existing configuration is used in order to discharge grinding dust from the porous member and the holding surface. Therefore, since the structure added for discharging grinding waste can be reduced, it is possible to discharge grinding waste while avoiding an increase in the size of the present grinding apparatus.

It is a perspective view which shows the structure of a grinding apparatus. It is explanatory drawing which shows a 1st holding process and a 2nd holding process. It is explanatory drawing which shows a fluid ejection process. It is explanatory drawing which shows a lower surface washing process. It is explanatory drawing which shows the modification of the pad of a carrying out mechanism.

As shown in FIG. 1, a grinding apparatus 1 according to this embodiment is an apparatus for grinding a wafer 100, which is an example of a workpiece. A wafer 100 is, for example, a circular plate-like workpiece and has a front surface 101 and a back surface 102 . A back surface 102 of the wafer 100 is a surface to be ground. Further, the wafer 100 also functions as a plate-like object used when removing grinding dust from the porous member 21 and the holding surface 22 .

The grinding device 1 has a first device base 10 and a second device base 11 arranged behind the first device base 10 (on the +Y direction side).

A first cassette stage 160 and a second cassette stage 162 are provided on the -Y direction side of the first device base 10 . A first cassette 161 containing wafers 100 before processing is mounted on the first cassette stage 160 . A second cassette 163 that accommodates the processed wafers 100 is mounted on the second cassette stage 162 .

The first cassette 161 and the second cassette 163 are internally provided with a plurality of shelves, each containing one wafer 100 . That is, the first cassette 161 and the second cassette 163 accommodate a plurality of wafers 100 like shelves.

The openings (not shown) of the first cassette 161 and the second cassette 163 face the +Y direction. A robot 155 is arranged on the +Y direction side of these openings. The robot 155 has a holding surface for holding the wafer 100 . The robot 155 loads (stores) the processed wafer 100 into the second cassette 163 . Further, the robot 155 takes out the unprocessed wafer 100 from the first cassette 161 and places it on the temporary placement table 154 of the temporary placement mechanism 152 .

The temporary placement mechanism 152 is used to temporarily place the wafers 100 taken out from the first cassette 161 and is provided at a position adjacent to the robot 155 . The temporary placement mechanism 152 has a temporary placement table 154 and an alignment member 153 . The alignment member 153 includes a plurality of alignment pins arranged outside so as to surround the temporary placement table 154 and a slider for moving the alignment pins in the radial direction of the temporary placement table 154 . In the alignment member 153 , the alignment pins are moved toward the center in the radial direction of the temporary placement table 154 , thereby reducing the diameter of the circle connecting the alignment pins. As a result, the wafer 100 placed on the temporary placement table 154 is aligned (centered) at a predetermined position where the center of the temporary placement table 154 and the center of the wafer 100 are aligned.

A loading mechanism 170 is provided at a position adjacent to the temporary placement mechanism 152 . The loading mechanism 170 holds the wafer 100 temporarily placed on the temporary placement mechanism 152 and loads and places it on the holding surface 22 of the chuck table 20 .

The chuck table 20 is an example of a holding member that holds the wafer 100 and has a holding surface 22 that holds the wafer 100 by suction. The holding surface 22 can be connected to a suction source 47 (see FIG. 2) to hold the wafer 100 by suction. The chuck table 20 is rotatable about a central axis passing through the center of the holding surface 22 and extending in the Z-axis direction, while holding the wafer 100 by suction on the holding surface 22 .

In this embodiment, two chuck tables 20 are arranged on a circle around the center of the turntable 6 on the upper surface of the turntable 6 arranged on the second device base 11 . A rotation shaft (not shown) for rotating the turntable 6 is arranged at the center of the turntable 6 . The turntable 6 can rotate about an axis extending in the Z-axis direction by this rotating shaft. The two chuck tables 20 revolve as the turntable 6 rotates. Thereby, the chuck table 20 can be positioned near the temporary placement mechanism 152 and below the grinding mechanism 70 .

A column 15 is erected on the +Y direction side of the second device base 11 . A grinding mechanism 70 for grinding the wafer 100 and a grinding feed mechanism 60 are provided on the front surface of the column 15 .

The grinding feed mechanism 60 relatively moves the chuck table 20 and the grinding wheel 77 of the grinding mechanism 70 in the Z-axis direction (grinding feed direction) perpendicular to the holding surface 22 . In this embodiment, the grinding feed mechanism 60 is configured to move the grinding wheel 77 in the Z-axis direction with respect to the chuck table 20 .

The grinding feed mechanism 60 includes a pair of Z-axis guide rails 61 parallel to the Z-axis direction, a Z-axis moving table 63 sliding on the Z-axis guide rails 61, a Z-axis ball screw 62 parallel to the Z-axis guide rails 61, a Z It has an axis motor 64 and a holder 66 attached to the Z-axis movement table 63 . Holder 66 supports grinding mechanism 70 .

The Z-axis moving table 63 is slidably installed on the Z-axis guide rail 61 . A nut portion (not shown) is fixed to the Z-axis moving table 63 . A Z-axis ball screw 62 is screwed into this nut portion. The Z-axis motor 64 is connected to one end of the Z-axis ball screw 62 .

In the grinding feed mechanism 60 , the Z-axis motor 64 rotates the Z-axis ball screw 62 to move the Z-axis moving table 63 along the Z-axis guide rail 61 in the Z-axis direction. As a result, the holder 66 attached to the Z-axis moving table 63 and the grinding mechanism 70 supported by the holder 66 also move together with the Z-axis moving table 63 in the Z-axis direction.

The grinding mechanism 70 grinds the wafer 100 suction-held by the holding surface 22 of the chuck table 20 with a grinding wheel 77 . The grinding mechanism 70 includes a spindle housing 71 fixed to a holder 66, a spindle 72 rotatably held by the spindle housing 71, a spindle motor 73 for rotating the spindle 72, a wheel mount 74 attached to the lower end of the spindle 72, and a grinding wheel 75 supported on a wheel mount 74 .

The spindle housing 71 is held by the holder 66 so as to extend in the Z-axis direction. The spindle 72 extends in the Z-axis direction perpendicular to the holding surface 22 of the chuck table 20 and is rotatably supported by the spindle housing 71 .

The spindle motor 73 is connected to the upper end side of the spindle 72 . The spindle motor 73 rotates the spindle 72 around a rotation axis extending in the Z-axis direction.

The wheel mount 74 is disc-shaped and fixed to the lower end (tip) of the spindle 72 . A wheel mount 74 supports a grinding wheel 75 .

The grinding wheel 75 is formed to have an outer diameter approximately the same as the outer diameter of the wheel mount 74 . Grinding wheel 75 includes an annular wheel base 76 formed from a metallic material. A plurality of grinding wheels 77 arranged in an annular shape are fixed to the lower surface of the wheel base 76 over the entire circumference. The grinding wheel 77 is rotated about its center by the spindle motor 73 together with the spindle 72 to grind the back surface 102 of the wafer 100 held on the chuck table 20 .

The wafer 100 after grinding is unloaded by the unloading mechanism 172 . The unloading mechanism 172 holds the wafer 100 held on the holding surface 22 of the chuck table 20 and unloads it from the holding surface 22 . The unloading mechanism 172 transports the wafer 100 unloaded from the holding surface 22 to the spinner table 157 of the single-wafer spinner cleaning mechanism 156 . The configuration of the unloading mechanism 172 will be described later.

A spinner cleaning mechanism 156 is a spinner cleaning unit that cleans the wafer 100 . The spinner cleaning mechanism 156 has a spinner table 157 that holds the wafer 100 and a nozzle 158 that sprays cleaning water and dry air toward the spinner table 157 .

In the spinner cleaning mechanism 156, a spinner table 157 holding the wafer 100 rotates, and cleaning water is sprayed toward the wafer 100 to clean the wafer 100 with the spinner. Dry air is then blown onto the wafer 100 to dry the wafer 100 .

The wafers 100 cleaned by the spinner cleaning mechanism 156 are transferred to the second cassette 163 on the second cassette stage 162 by the robot 155 .

A lower surface cleaning mechanism 180 is arranged between the turntable 6 and the spinner cleaning mechanism 156 . The undersurface cleaning mechanism 180 is used to clean the surface 101 that is the underside of the wafer 100 transferred from the chuck table 20 to the spinner cleaning mechanism 156 by the unloading mechanism 172 . That is, the lower surface cleaning mechanism 180 cleans the front surface 101 of the wafer 100 held by the unloading mechanism 172 .

Here, the configuration of the chuck table 20 will be described.
As shown in FIG. 2, the chuck table 20 is a circular plate-shaped table for holding the wafer 100 . The chuck table 20 includes a circular plate-shaped porous member 21 and a frame 23 that supports the porous member 21 . The porous member 21 can be communicated with a suction source 47 . The suction force from the suction source 47 is transmitted to the holding surface 22 , which is the top surface of the porous member 21 , so that the chuck table 20 can hold the wafer 100 by suction on the holding surface 22 of the porous member 21 .

Also, the chuck table 20 is rotatable by a rotating mechanism 30 . The rotating mechanism 30 is, for example, a pulley mechanism, and includes a motor 31 serving as a drive source, a driving pulley 32 attached to the shaft of the motor 31, a driven pulley 34 connected to the driving pulley 32 via an endless belt 33, and a rotating shaft 35 that supports the driven pulley 34 .

The rotary shaft 35 is connected directly below the center of the holding surface 22 on the lower surface of the chuck table 20 and extends perpendicularly to the holding surface 22 of the chuck table 20 . When the motor 31 rotates the driving pulley 32 , the endless belt 33 rotates with the rotation of the driving pulley 32 . As the endless belt 33 rotates, the driven pulley 34 and the rotating shaft 35 rotate. Thereby, the chuck table 20 is rotated around the center of the holding surface 22 .

The grinding machine 1 also includes a fluid circulation mechanism 40 . The fluid circulation mechanism 40 is a mechanism for supplying air or water, which is a fluid, to the holding surface 22 of the chuck table 20 or for applying a suction force to the holding surface 22 .

The fluid circulation mechanism 40 includes a suction groove 403 , a suction channel 470 communicating with the suction groove 403 , a rotary joint 460 connected to the rotary shaft 35 , and a suction pipe 471 communicating with the suction channel 470 . there is

The suction groove 403 is provided on the bottom surface of the recess of the frame 23 of the chuck table 20 so as to contact the bottom surface of the porous member 21 . The suction groove 403 is formed concentrically around the center of the chuck table 20 .

The suction channel 470 extends from the bottom surface of the suction groove 403 so as to pass through the frame 23 , the rotating shaft 35 and the rotary joint 460 .

The suction channel 470 is connected to a suction pipe 471 outside the rotary joint 460 . One end of the suction pipe 471 communicates with the suction channel 470 . A suction source 47 is connected to the other end of the suction pipe 471 . The suction source 47 has, for example, an ejector mechanism, a vacuum generator, or the like, communicates with the porous member 21 of the chuck table 20, and is used to apply a suction force to the holding surface 22, which is the upper surface thereof.

A suction opening/closing valve 475 and a suction flow rate adjusting section 473 are arranged in order from the suction source 47 toward the suction channel 470 side in the suction pipe 471 . The suction opening/closing valve 475 switches the state of communication between the suction pipe 471 and the suction source 47 . The suction flow rate adjusting unit 473 is, for example, a proportional control valve, and changes the diameter of the internal orifice when the suction opening/closing valve 475 is open to change the suction power transmitted from the suction source 47 to the holding surface 22 of the porous member 21 . Used to regulate force.
The suction flow rate adjusting unit 473 may be a needle valve or a gate valve for manually adjusting the orifice diameter.

Furthermore, an air pipe 481 is communicated with the suction pipe 471 . The air pipe 481 is a pipe for communicating between the holding surface 22 of the chuck table 20 and the air supply source 48 .

One end side of the air pipe 481 communicates with the suction flow path 470 via the suction pipe 471 . An air supply source 48 is connected to the other end of the air pipe 481 . The air supply source 48 has a compressor or the like and is used to supply air to the holding surface 22 of the chuck table 20 .

An air supply opening/closing valve 485 and an air adjuster 483 are arranged in order from the air supply source 48 toward the suction flow path 470 in the air pipe 481 . The air supply opening/closing valve 485 switches the state of communication between the air pipe 481 and the air supply source 48 . The air adjustment unit 483 is, for example, a proportional control valve, and adjusts the flow rate of air sent from the air supply source 48 to the holding surface 22 by changing the internal orifice diameter when the air supply opening/closing valve 485 is open. used to
The air adjusting portion 483 may be a needle valve or a gate valve for manually adjusting the orifice diameter.

A pressure sensor 487 is provided in the air pipe 481 . The pressure sensor 487 detects the suction force of the holding surface 22 by detecting the pressure value of this air pipe 481 .

A water pipe 491 is connected to the air pipe 481 . The water pipe 491 is a pipe for communicating the holding surface 22 of the chuck table 20 and the water supply source 49 .

One end side of the water pipe 491 communicates with the suction flow path 470 via the air pipe 481 and the suction pipe 471 . A water supply source 49 is connected to the other end of the water pipe 491 . The water supply source 49 has a pump or the like and is used to supply water to the holding surface 22 of the chuck table 20 .

A water supply opening/closing valve 495 and a water adjustment unit 493 are arranged in order from the water supply source 49 toward the suction flow path 470 side in the water pipe 491 . The water supply opening/closing valve 495 switches the state of communication between the water pipe 491 and the water supply source 49 . The water adjustment unit 493 is, for example, a proportional control valve, and adjusts the flow rate of water sent from the water supply source 49 to the holding surface 22 by changing the internal orifice diameter when the water supply opening/closing valve 495 is open. used to
The water adjustment unit 493 may be a needle valve or gate valve for manually adjusting the orifice diameter.

Next, configurations of the loading mechanism 170 and the unloading mechanism 172 will be described. In addition, in this embodiment, the carrying-in mechanism 170 and the carrying-out mechanism 172 have the same configuration. Therefore, the configuration of the unloading mechanism 172 will be described below.

As shown in FIG. 2, the carry-out mechanism 172 includes a disc-shaped pad 80 and an arm 81 that suspends the pad 80 vertically. One end of the arm 81 is connected to the upper end of a rotating column 82 extending in the Z-axis direction from the first device base 10 (see FIG. 1). The rotating column portion 82 is connected to a motor 94 that rotates the rotating column portion 82 together with the arm 81 and a vertical movement mechanism 95 that vertically moves the rotating column portion 82 together with the arm 81 .

A disk member 84 is connected to the other end of the arm 81 via a support 83 . A plurality of (for example, three) through-holes 85 are formed through the disk member 84 at equal intervals on the circumference. A bolt 86 connected to the pad 80 is inserted into the through hole 85 .

The bolt 86 has a shaft portion 87 having a slightly smaller diameter than the through hole 85 and a head portion 88 formed at the upper end of the shaft portion 87 .
The shaft portion 87 is loosely fitted through the through hole 85 . A lower end of the shaft portion 87 is connected to the upper surface of the frame 91 of the pad 80 . The head 88 is formed to have a larger diameter than the through hole 85 and limits the lowering range of the bolt 86 .
Also, the bolt 86 has a spring 860 as a shock absorbing member around the shaft portion 87 . The upper end of the spring 860 is in contact with the lower surface of the disk member 84 , while the lower end of the spring 860 is in contact with the upper surface of the frame 91 of the pad 80 . A spring 860 urges the disk member 84 and the pad 80 away from each other.

The arm 81 can suspend the pad 80 while absorbing impact applied to the pad 80 via the disc member 84 and the bolt 86 having such a configuration.

The disk-shaped pad 80 has, for example, an area slightly larger than the area of the wafer 100, and includes a pad holding portion 90 made of a porous material and a frame 91 that supports the pad holding portion 90. there is The lower surface of the pad holding portion 90 serves as a pad holding surface 92 for sucking and holding the back surface 102 of the wafer 100 .

The carry-out mechanism 172 also includes a suction path 89 . The suction path 89 extends through the arm 81 , the strut 83 , the disk member 84 and the frame 91 of the pad 80 , and its lower end is connected to the upper surface of the pad holding portion 90 . Also, the upper end of the suction path 89 is connected to a suction source 99 .

Therefore, in the unloading mechanism 172 , the suction source 99 is connected to the suction path 89 in a state where the pad holding surface 92 is in contact with the wafer 100 held on the holding surface 22 of the chuck table 20 . is transmitted to the pad holding surface 92, and the wafer 100 can be held by the pad holding surface 92 by suction.

By rotating and raising and lowering the rotary column 82 and the arm 81 by the motor 94 and the vertical movement mechanism 95, the pad 80 holding the wafer 100 is rotated and raised, and the wafer 100 is unloaded from the chuck table 20. can do.

The grinding machine 1 also has a control unit 7 for controlling the grinding machine 1 therein, as shown in FIG. The control unit 7 includes a CPU that performs arithmetic processing according to a control program, a storage medium such as a memory, and the like. The control unit 7 executes various processes and centrally controls each component of the grinding apparatus 1 .

For example, the control unit 7 controls the above-described members of the grinding device 1 to grind the wafer 100 .

In addition, the control unit 7 periodically performs self-grinding for grinding the holding surface 22 with the grinding wheel 77 of the grinding mechanism 70 in order to prevent the suction force of the holding surface 22, which is the surface of the porous member 21, of the chuck table 20 from decreasing. Grinding dust on the outer peripheral portion of the holding surface 22 is removed.
In addition, when the holding surface 22 is ground, the fluid may or may not be ejected from the holding surface 22 .

In this self-grinding, the grinding dust of the porous member 21 generated by grinding the holding surface 22, the grinding dust of the wafer 100 remaining on the outer peripheral portion of the holding surface 22, and the grinding of the holding surface 22 are performed. Grinding waste including abrasive grains dropped from the grinding wheel 77 may enter the inside of the porous member 21 . Therefore, the control unit 7 performs a cleaning process to remove the grinding dust from the porous member 21 and the holding surface 22 .
The cleaning process in this embodiment will be described below.

[First holding step]
In the cleaning process, the controller 7 first takes out the wafer 100 before processing from the first cassette 161 by the robot 155, places it on the temporary placement table 154 of the temporary placement mechanism 152, and places the wafer 100 in a predetermined position. to align.

Furthermore, the controller 7 controls the loading mechanism 170 to hold the wafer 100 on the temporary placement mechanism 152 . That is, the controller 7 causes the pad holding surface 92 to come into contact with the wafer 100 on the temporary placement mechanism 152 by rotating and raising and lowering the pad 80 by means of the motor 94 and the vertical movement mechanism 95 of the loading mechanism 170 shown in FIG. Let By connecting the suction source 99 to the suction path 89 in this state, the loading mechanism 170 suction-holds the wafer 100 with the pad holding surface 92 of the pad 80 .

After that, the controller 7 places the wafer 100 on the holding surface 22 of the chuck table 20 positioned near the temporary placement mechanism 152 by rotating and raising and lowering the pad 80 of the loading mechanism 170 , and lifts the pad 80 . The chuck table 20 is retracted. As a result, the holding surface 22 is covered with the wafer 100 as shown in FIG.

After that, the control unit 7 opens the suction opening/closing valve 475 shown in FIG. 2 and adjusts the orifice diameter of the suction flow rate adjusting unit 473 to allow the porous member 21 of the chuck table 20 to communicate with the suction source 47 . Thereby, the holding surface 22 of the chuck table 20 holds the wafer 100 by suction. The orifice diameter of the suction flow rate adjusting section 473 may be fully open.

[Second holding step]
Next, the controller 7 holds the wafer 100 suction-held by the holding surface 22 by the unloading mechanism 172 . That is, the controller 7 moves the pad holding surface 92 onto the wafer 100 held on the holding surface 22 of the chuck table 20 by turning and raising/lowering the pad 80 by means of the motor 94 and the vertical movement mechanism 95 of the unloading mechanism 172 . make contact. By connecting the suction source 99 to the suction path 89 in this state, the unloading mechanism 172 suction-holds the wafer 100 by the pad holding surface 92 of the pad 80 .

As a result, the wafer 100 is held by the unloading mechanism 172 while covering the holding surface 22 of the chuck table 20, as shown in FIG. After that, the controller 7 closes the suction open/close valve 475 to stop the suction and holding of the wafer 100 by the holding surface 22 of the chuck table 20 .

[Fluid jetting process]
Next, the control unit 7 ejects two fluids, which are mixed fluids of water and air, from the holding surface 22 covered with the wafer 100 . As a result, the two fluids ejected from the holding surface 22 flow outward in the diametrical direction of the holding surface 22 between the holding surface 22 and the wafer 100 to remove grinding waste from the porous member 21 and the holding surface 22 of the chuck table 20. do.

That is, the control unit 7 opens the air supply opening/closing valve 485 and the water supply opening/closing valve 495, adjusts the orifice diameter of the air adjustment unit 483 and the orifice diameter of the water adjustment unit 493, and rotates the porous member 21 of the chuck table 20. , air supply 48 and water supply 49 . As a result, the control unit 7 supplies predetermined amounts of two fluids, air and water, to the porous member 21 as indicated by an arrow 501 in FIG.
The orifice diameter of the air adjusting portion 483 and the orifice diameter of the water adjusting portion 493 may be fully opened.

The two fluids supplied to the porous member 21 flow upward through the porous member 21 and are ejected from the holding surface 22 together with the grinding waste inside the porous member 21 . As a result, as shown in FIG. 3, the wafer 100 held by the unloading mechanism 172 while covering the holding surface 22 resists the biasing force of the spring 860 by the two fluids 200 as indicated by the arrow 503. , and rises from the holding surface 22 together with the pad 80 . Then, the two-fluid 200 containing the grinding dust flows out from the gap between the holding surface 22 and the wafer 100 to the outside in the radial direction of the holding surface 22 .
At this time, as shown in FIG. 3 , the spring 860 contracts as the pad 80 rises, and the head 88 of the bolt 86 rises from the upper surface of the disk member 84 .

After a predetermined period of time has elapsed from the start of ejection of the two fluids 200 , the controller 7 closes the air supply opening/closing valve 485 and the water supply opening/closing valve 495 to stop the ejection of the two fluids 200 . After that, the controller 7 causes the wafer 100 to separate from the holding surface 22 by rotating and raising and lowering the pad 80 of the unloading mechanism 172 holding the wafer 100 .

As described above, in the present embodiment, the holding surface 22 is covered with the wafer 100 , and the two fluids 200 are caused to flow from below the porous member 21 toward the holding surface 22 . Grinding debris that has entered can be discharged from the porous member 21 and the holding surface 22 . Therefore, when the wafer 100 is ground by the grinding mechanism 70, it is possible to suppress the presence of grinding debris between the holding surface 22 and the wafer 100, so that the wafer 100 can be ground to a uniform thickness. is.

In addition, in this embodiment, the wafer 100 which is the workpiece and the carry-out mechanism 172 which is an existing structure are used in order to discharge the grinding dust from the porous member 21 . Therefore, the configuration added for discharging the grinding waste from the porous member 21 and the holding surface 22 can be reduced, so it is possible to discharge the grinding waste while avoiding an increase in the size of the grinding apparatus 1. .

In the fluid jetting process, if the two fluids 200 are supplied to the porous member 21 in a state where the holding surface 22 is not covered with the wafer 100, the two fluids 200 pass through only the portion of the porous member 21 through which it is easy to pass. , from the holding surface 22 . Therefore, it is difficult to discharge the grinding dust from the entire porous member 21 .

In this regard, in this embodiment, the two fluids 200 are supplied to the porous member 21 while the holding surface 22 is covered with the wafer 100 held by the unloading mechanism 172 . As a result, the two fluids 200 can be ejected from the holding surface 22 while the holding surface 22 is under pressure. Therefore, it is possible to discharge the grinding dust from almost the entire area inside the porous member 21 .

After ejecting the two fluids 200 from the holding surface 22, the control unit 7 cleans the surface 101, which is the lower surface of the wafer 100 separated from the holding surface 22, by the lower surface cleaning mechanism 180 shown in FIG. The holding surface 22 may be covered with the wafer 100 again, and the two fluids 200 may be ejected from the holding surface 22 to remove grinding dust from the porous member 21 and the holding surface 22 .

In this case, the controller 7 performs the following lower surface cleaning process after the fluid jetting process.

[Lower surface washing process]
The controller 7 causes the wafer 100 to be separated from the holding surface 22 by turning and raising and lowering the pad 80 of the unloading mechanism 172 holding the wafer 100, so that the wafer 100 is positioned directly above the lower surface cleaning mechanism 180 as shown in FIG. to be placed.

The undersurface cleaning mechanism 180 includes a sponge roller 181, a hollow shaft 182 inserted into the sponge roller 181 to hold the sponge roller 181, and a base member 183 supporting the shaft 182 so as to rotate freely. The shaft 182 is connected to a water source 185 via a joint 184, and water supplied from the water source 185 can be supplied to the sponge roller 181 through holes provided on the surface of the shaft 182. .

Then, as shown in FIG. 4, the control unit 7 adjusts the position of the pad 80 of the unloading mechanism 172 holding the wafer 100 so that the front surface 101 of the wafer 100 is in contact with the sponge roller 181 of the lower surface cleaning mechanism 180. do. Further, while supplying water to the sponge rollers 181 of the lower surface cleaning mechanism 180, the controller 7 causes the lower surface cleaning mechanism 180 to move the pad 80 holding the wafer 100 as indicated by an arrow 505 in FIG. Move horizontally. Thereby, the sponge roller 181 containing water comes into contact with the surface 101 of the wafer 100 while rotating, and the surface 101 is cleaned.

After the entire front surface 101 of the wafer 100 has been cleaned, the controller 7 ends the lower surface cleaning step, rotates and raises and lowers the pad 80 of the unloading mechanism 172 , and covers the holding surface 22 of the chuck table 20 with the wafer 100 . . Then, the control unit 7 performs the above-described fluid jetting process again to remove grinding debris from the porous member 21 and the holding surface 22 .

In this configuration, removal of grinding dust from the porous member 21 and the holding surface 22 can be repeatedly performed while cleaning the front surface 101 that is the lower surface of the wafer 100 . Therefore, it is possible to satisfactorily remove grinding debris from the porous member 21 and the holding surface 22 .

Also, in the above-described embodiment, the area of the pad 80 in the unloading mechanism 172 is slightly larger than the area of the wafer 100, as shown in FIG. Alternatively, pad 80 may have an area smaller than the area of wafer 100, as shown in FIG.

In this configuration, pad 80 does not hold the outer peripheral portion of wafer 100 . Therefore, when the two fluids 200 are ejected from the holding surface 22 of the chuck table 20 in the fluid ejecting process, a gap is likely to occur between the holding surface 22 and the outer peripheral portion of the wafer 100 . Therefore, the two-fluid 200 containing the grinding waste is easily discharged from the gap between the holding surface 22 and the wafer 100 to the radially outer side of the holding surface 22, so that the grinding waste can be removed well from the porous member 21 and the holding surface 22. becomes possible.

Further, in the above-described embodiment, the wafer 100 is used as the plate-like object that covers the holding surface 22 of the chuck table 20 during the fluid jetting process. In this regard, a dummy wafer or a plate may be used as the plate-like object covering the holding surface 22 . A dummy wafer is, for example, a wafer that is not to be ground by the grinding apparatus 1 . Also, the flat plate is, for example, a plate for cleaning the porous member 21 . In this case, the dummy wafer or plate-like plate is stored in the first cassette 161 in advance, is taken out by the robot 155, and is held on the holding surface 22 of the chuck table 20 by suction in the first holding step.

In the above-described embodiment, the control unit 7 performs the fluid jetting process while the holding surface 22 of the chuck table 20 is covered with the wafer 100 held by the unloading mechanism 172 . Alternatively, the control unit 7 may perform the fluid jetting process while the holding surface 22 of the chuck table 20 is covered with the wafer 100 held by the loading mechanism 170 . In this case, in the second holding step, the loading mechanism 170 holds the wafer 100 suction-held on the holding surface 22 . Further, in this case, the undersurface cleaning mechanism 180 may be arranged near the loading mechanism 170 .

1: grinding device, 6: turntable, 7: control unit, 10: first device base,
11: second device base, 15: column, 20: chuck table,
21: porous member, 22: holding surface, 23: frame, 30: rotation mechanism, 31: motor,
32: driving pulley, 33: endless belt, 34: driven pulley, 35: rotating shaft,
40: fluid circulation mechanism, 47: suction source, 48: air supply source, 49: water supply source,
60: Grinding feed mechanism, 61: Z-axis guide rail, 62: Z-axis ball screw,
63: Z-axis moving table, 64: Z-axis motor, 66: Holder,
70: grinding mechanism, 71: spindle housing, 72: spindle,
73: spindle motor, 74: wheel mount, 75: grinding wheel,
76: Wheel base, 77: Grinding wheel,
80: Pad, 81: Arm, 82: Rotating Column, 83: Post, 84: Disc Member,
85: through hole, 86: bolt, 87: shaft, 88: head, 89: suction path,
90: pad holding part, 91: frame, 92: pad holding surface, 94: motor,
95: vertical movement mechanism, 99: suction source, 100: wafer, 101: front surface, 102: back surface,
152: temporary placement mechanism, 153: alignment member, 154: temporary placement table,
155: robots,
156: Spinner cleaning mechanism, 157: Spinner table, 158: Nozzle,
160: first cassette stage, 161: first cassette,
162: second cassette stage, 163: second cassette,
170: Carry-in mechanism, 172: Carry-out mechanism,
180: lower surface cleaning mechanism, 181: sponge roller, 182: shaft,
183: base member, 184: joint, 185: water source, 200: two fluids, 403: suction groove,
460: rotary joint, 470: suction channel, 471: suction pipe,
473: suction flow rate adjusting unit, 475: suction opening/closing valve, 481: air pipe,
483: Air adjustment unit, 485: Air supply opening/closing valve, 487: Pressure sensor,
491: water pipe, 493: water adjustment unit, 495: water supply opening/closing valve, 860: spring

Claims (2)

A chuck table for sucking and holding a plate-like object by the holding surface of the porous member, a grinding mechanism for grinding the plate-like object sucked and held by the holding surface with a grinding wheel, and a carrying-in for holding the plate-like object and carrying it into the holding surface. A grinding apparatus comprising a mechanism, a carry-out mechanism for holding a plate-shaped object and carrying it out from the holding surface, and a control unit,
The control unit
causing the holding surface to hold a plate-like object by suction;
holding the plate-like object sucked and held by the holding surface by the carry-out mechanism or the carry-in mechanism;
controlling the jetting of two fluids, which is a mixture of water and air, from the holding surface covered with the plate-like object;
The two fluids ejected from the holding surface flow outward in the diametrical direction of the holding surface between the holding surface and the plate-like object to remove grinding debris from the porous member and the holding surface.
grinding equipment. further comprising a lower surface cleaning mechanism for cleaning the lower surface of the plate-shaped object held by the carry-out mechanism or the carry-in mechanism;
After ejecting the two fluids from the holding surface, the control unit cleans the lower surface of the plate-like object separated from the holding surface by the lower surface washing mechanism, and again cleans the holding surface of the plate-like object. and ejecting the two fluids from the holding surface to remove grinding debris from the porous member and the holding surface.
The grinding apparatus according to claim 1.

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