JP2021175586A - Grinding device and method - Google Patents

Abstract

To reduce pollution of a chuck table during idling.SOLUTION: A grinding device for grinding a workpiece comprises: a chuck table rotatable around a prescribed axis of rotation; a grinding unit which has a spindle and an annular grinding wheel installed in a lower end part of the spindle, and rotates the grinding wheel while supplying grinding water from a grinding water supply port provided in the grinding wheel; a cover member covering an upper part of the chuck table and the grinding wheel; a plate-like object housing part for housing a plate-like object for protecting at least a part of an upper surface of the chuck table; and a control unit for controlling operations of the chuck table and the grinding unit. The grinding water is supplied with the plate-like object being held by at least a part of the upper surface of the chuck table, and idling for rotating the grinding wheel and the chuck table is performed.SELECTED DRAWING: Figure 1

Description

The present invention relates to a grinding apparatus that grinds a workpiece while sucking and holding the workpiece on a chuck table, and a method of idling in the grinding apparatus.

For example, a grinding device is used to grind and thin the back surface side of a workpiece such as a semiconductor device wafer having a device formed on the front surface side. Before grinding with the grinding device, idling (that is, warm-up operation) is usually performed with the holding surface of the chuck table exposed.

By idling, it is confirmed that there is no problem with the grinding device, and the grinding unit including the grinding wheel and the chuck table that sucks and holds the workpiece are adjusted to the same temperature as during grinding to grind with a predetermined accuracy. Condition the grinding equipment so that it can be performed.

However, when idling, the grinding wheel is rotated while supplying grinding water from the grinding wheel (see, for example, Patent Document 1). Therefore, the grinding water is scattered in the grinding chamber where the grinding wheel and the chuck table are arranged.

The scattered grinding water may fall on the chuck table in a state of containing grinding dust adhering to the inner wall of the grinding chamber (particularly, the ceiling portion of the grinding chamber). Further, the scattered grinding water may fall on the chuck table in a state of containing the grinding dust adhering to the grinding wheel itself.

Japanese Unexamined Patent Publication No. 2003-326458

When grinding water containing grinding debris adheres to the chuck table, the chuck table is contaminated with work debris. When grinding a work piece using a chuck table contaminated with work chips or the like, the work piece is also contaminated, which may lead to poor device characteristics. The present invention has been made in view of the above problems, and an object of the present invention is to reduce contamination of the chuck table during idling.

According to one aspect of the present invention, it is a grinding device that grinds an workpiece, and is an annular grinding machine mounted on a chuck table, a spindle, and a lower end portion of the spindle, which can rotate around a predetermined rotation axis. A grinding unit having a wheel and rotating the grinding wheel while supplying grinding water from a grinding water supply port provided on the grinding wheel, a chuck table, and a cover member covering the upper part of the grinding wheel. The chuck table includes a plate-shaped material accommodating portion for accommodating a plate-shaped material for protecting at least a part of the upper surface of the chuck table, and a control unit for controlling the operation of the chuck table and the grinding unit. Provided is a grinding device characterized by supplying the grinding water and idling to rotate the grinding wheel and the chuck table while holding the plate-like object on at least a part of the upper surface.

Preferably, the chuck table is arranged so as to surround a disk-shaped porous plate and the outer periphery of the porous plate, and the annular porous member having a smaller average pore size than the porous plate and the annular porous member. The outer diameter of the upper surface of the porous plate is smaller than the outer diameter of the plate-shaped object, and the outer diameter of the upper surface of the porous plate is smaller than the outer diameter of the plate-like object. The entire upper surface of the porous plate is covered with the plate-like material.

Further, preferably, the outer diameter of the upper surface of the annular porous member is smaller than the outer diameter of the plate-shaped object, and when idling, the entire upper surface of the porous plate and the annular porous member is covered with the plate-shaped object. ..

Further, preferably, the outer diameter of the upper surface of the frame is smaller than the outer diameter of the plate, and when idling, the porous plate, the annular porous member, and the entire upper surface of the frame are the plate. Covered with.

Also, preferably, the plate-like material is made of a non-metal material.

According to another aspect of the present invention, there is a method of idling in a grinding apparatus, wherein a plate-shaped object holding step for holding a plate-shaped object on at least a part of the upper surface of a chuck table and a plate-shaped object holding step for holding the plate-shaped object. After that, in a state where the chuck table is arranged below the cover member, a grinding water supply provided on the grinding wheel of a grinding unit having a spindle and an annular grinding wheel mounted on the lower end of the spindle. Provided is a method for performing idling in a grinding apparatus, which comprises supplying grinding water from a mouth and an idling step for rotating the grinding wheel and the chuck table in a predetermined direction.

In the grinding apparatus according to one aspect of the present invention, while holding a plate-like object on the upper surface of the chuck table, grinding water is supplied and idling is performed to rotate the grinding wheel and the chuck table. Therefore, even if the grinding debris adhering to the inner wall of the cover member or the grinding wheel falls on the chuck table together with the grinding water, the contamination of the area covered with the plate-like material can be reduced.

It is a perspective view of the grinding apparatus which concerns on 1st Embodiment. It is sectional drawing of a chuck table and the like. It is a partial cross-sectional side view of a rough grinding unit and the like. It is a flow chart which shows the procedure such as idling. FIG. 5A is a partial cross-sectional side view of the protective substrate or the like according to the second embodiment, and FIG. 5B is a partial cross-sectional side view of the protective substrate or the like according to the third embodiment. be. It is a perspective view of the grinding apparatus which concerns on 4th Embodiment.

An embodiment according to one aspect of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a perspective view of the grinding device 2 according to the first embodiment. The X-axis direction, the Y-axis direction (front-back direction), and the Z-axis direction (vertical direction, grinding feed direction) shown in FIG. 1 are orthogonal to each other.

The grinding device 2 has a substantially rectangular parallelepiped base 4 that supports the components. A recess 4a is formed in front of the base 4 (one in the Y-axis direction), and a transfer robot 6 is provided in the recess 4a.

A cassette mounting area 8a and a cassette mounting area 8b exist on both sides of the recess 4a so as to sandwich the recess 4a in the X-axis direction. On the cassette mounting area 8a, a cassette 10a containing one or more workpieces 11 (plate-shaped objects) before processing is placed.

Each of the cassettes 10a contains one or a plurality of workpieces 11 to which a resin protective tape 13 is attached on the surface 11a side. Further, a cassette 10b for accommodating one or more workpieces 11 after processing is placed on the cassette mounting area 8b.

The workpiece 11 is, for example, a disk-shaped wafer (Si wafer) made of Si (silicon) in which a plurality of devices (not shown) are formed on the surface 11a side. However, the workpiece 11 is not limited to a Si wafer, and may be a wafer formed of a compound such as SiC (silicon carbide) or GaN (gallium nitride), or a wafer formed of another material. You may.

Behind the cassette mounting area 8a (the other in the Y-axis direction), a positioning table 12 for determining the position of the workpiece 11 carried out by the transfer robot 6 is provided. Three prismatic legs 14a are arranged around the positioning table 12, and a flat plate-shaped mounting table 14b is arranged on the three legs 14a.

On the mounting table 14b, a box-shaped accommodating portion (plate-shaped object accommodating portion) 14c accommodating one or more protective substrates (plate-shaped objects) 19 is provided. The protective substrate 19 is used to protect at least a part of the upper surface of the chuck table 20 as described later.

The protective substrate 19 of the present embodiment has substantially the same diameter as the workpiece 11 and is a disk-shaped substrate made of a non-metal material. By using the protective substrate 19 made of a non-metal material, it is possible to prevent the upper surface of the chuck table 20 from being contaminated with metal.

The protective substrate 19 may be made of the same material as the workpiece 11. For example, when the workpiece 11 is a Si wafer, a Si substrate (Si wafer) is used as the protective substrate 19, and when the workpiece 11 is a SiC wafer, the SiC substrate (SiC wafer) is used as the protective substrate 19. ) Is used.

By using the protective substrate 19 made of the same material as the work piece 11, it is possible to prevent the work piece 11 held by the chuck table 20 from being contaminated with a material different from the work piece 11.

A loading arm 16 having a disk-shaped pad at the tip for sucking and holding the workpiece 11 is provided in a region adjacent to the positioning table 12 in the X-axis direction. A disk-shaped turntable 18 is provided behind the base end portion of the loading arm 16.

A first rotary drive source (not shown) such as a motor is arranged on the lower surface side of the turntable 18. The first rotational drive source rotates the turntable 18 in a clockwise direction or a counterclockwise direction in a top view.

On the upper surface side of the turntable 18, three chuck tables 20 are provided so as to be separated from each other by approximately 120 degrees in the circumferential direction of the turntable 18. One chuck table 20 is arranged in the carry-in / carry-out area A closest to the loading arm 16.

There is one rough grinding area B that is approximately 120 degrees clockwise from the carry-in / carry-out area A and one finish grinding area C that is approximately 120 degrees counterclockwise from the carry-in / carry-out area A. The chuck table 20 is arranged.

Here, the structure of the chuck table 20 will be described with reference to FIG. FIG. 2 is a cross-sectional view of the chuck table 20 and the like. The chuck table 20 is fixed to the upper surface of the disk-shaped table base 22.

The chuck table 20 has a disk-shaped frame body 24 made of ceramics or the like. A disk-shaped recess 24a is formed on the upper surface side of the frame body 24, and the recess 24a has a disk-shaped porous plate 26 and an annular porous member arranged so as to surround the outer peripheral side surface 26a of the porous plate 26. 28 and are fixed.

That is, the outer peripheral side surface 28a of the annular porous member 28 is in contact with the inner peripheral side surface of the recess 24a and is surrounded by the frame body 24. Further, the porous plate 26 and the annular porous member 28 are supported by a support surface located at the bottom of the recess 24a. The support surface of the recess 24a is not shown in FIG.

On the bottom surface of the frame body 24, a plurality of flow paths 24b formed radially and flow paths 24c formed so as to penetrate the center of the bottom surface of the frame body 24 are formed. A suction source (not shown) such as a vacuum pump is connected to the flow path 24c, and when the suction source is operated, negative pressure is generated on the upper surface 26b of the porous plate 26 and the upper surface 28b of the annular porous member 28.

The annular porous member 28 is a barrier portion provided to prevent leakage, and the average pore size of the annular porous member 28 is smaller than the average pore size of the porous plate 26.

Since the annular porous member 28 is a dense porous member that is denser than the porous plate 26, the magnitude of the negative pressure generated on the upper surface 28b is the same as the negative pressure generated on the upper surface 26b even if they are connected to the same flow path 24b. Small compared to size.

Each of the upper surface 24d of the frame body 24, the upper surface 26b of the porous plate 26, and the upper surface 28b of the annular porous member 28 constitutes a part of the upper surface of the chuck table 20. The upper surfaces 24d, 26b, and 28b form a conical convex surface, and the convex surface serves as a holding surface 20a for sucking and holding the workpiece 11 and the like.

A second rotary drive source 22a (see FIG. 3) such as a motor is provided below the chuck table 20. The output shaft 22b of the second rotational drive source 22a is connected to the lower part of the table base 22. When the output shaft 22b is rotated, the chuck table 20 and the table base 22 rotate around the output shaft 22b (predetermined rotation shaft).

Returning to FIG. 1, a square columnar support structure 30a is provided behind the rough grinding region B of the turntable 18 so as to project from the upper surface of the base 4. A grinding feed unit 32 is provided on the front surface side of the support structure 30a.

The grinding feed unit 32 has a pair of Z-axis guide rails 34 fixed to the front surface of the support structure 30a and substantially parallel to the Z-axis direction. Note that FIG. 1 shows only one Z-axis guide rail 34. A Z-axis moving plate 36 is slidably attached to the pair of Z-axis guide rails 34.

A nut portion 38 (see FIG. 3) is provided on the rear (back surface) side of the Z-axis moving plate 36. A Z-axis ball screw 40 provided along the Z-axis direction between the pair of Z-axis guide rails 34 is connected to the nut portion 38 in a rotatable manner.

A Z-axis pulse motor 42 is connected to the upper end of the Z-axis ball screw 40. When the Z-axis ball screw 40 is rotated by the Z-axis pulse motor 42, the Z-axis moving plate 36 moves in the Z-axis direction along the Z-axis guide rail 34.

A rough grinding unit (grinding unit) 44a is fixed to the front surface of the Z-axis moving plate 36. Here, the configuration of the rough grinding unit 44a will be described with reference to FIGS. 1 and 3. FIG. 3 is a partial cross-sectional side view of the rough grinding unit 44a and the like.

The rough grinding unit 44a has a cylindrical holding member 46 fixed to the Z-axis moving plate 36. Inside the holding member 46, a cylindrical spindle housing 48 arranged substantially parallel to the Z-axis direction is provided.

A part of the cylindrical spindle 50 arranged substantially parallel to the Z-axis direction is housed in the spindle housing 48 in a rotatable state. A third rotary drive source 52 (see FIG. 1) such as a motor is connected to the upper end of the spindle 50.

A disk-shaped wheel mount 54 is fixed to the lower end of the spindle 50. An annular rough grinding wheel 56a is mounted on the lower surface of the wheel mount 54 by a fixing member (not shown) such as a screw.

Immediately below the rough grinding wheel 56a corresponds to the above-mentioned rough grinding region B. The rough grinding wheel 56a has an annular wheel base 58 made of a metal material such as an aluminum alloy, and a plurality of rough grinding wheels 60a mounted on the lower surface side of the wheel base 58.

The plurality of rough grinding wheels 60a are arranged in an annular shape along the circumference of the lower surface of the wheel base 58 so that a gap is provided between the adjacent rough grinding wheels 60a. The rough grinding wheel 60a is formed by mixing abrasive grains such as diamond and cBN (cubic boron nitride) with a binder such as metal, ceramics, and resin.

A plurality of openings (grinding water supply ports) 62 are provided inside the rough grinding wheel 60a of the wheel base 58 along the circumference of the lower surface of the wheel base 58. Further, the wheel base 58, the wheel mount 54, the spindle 50, and the like are provided with a flow path for supplying grinding water 64 such as pure water to the opening 62.

A grinding water supply unit 66 is connected to one end of the flow path. The grinding water supply unit 66 includes, for example, a tank in which the grinding water 64 is stored (not shown), a pump for supplying the grinding water 64 from the tank (not shown), and the like.

When the work piece 11 is ground by the rough grinding unit 44a, the chuck table 20 arranged in the rough grinding area B sucks and holds the surface 11a side of the work piece 11 via the protective tape 13. 20 and the rough grinding wheel 56a are each rotated in a predetermined direction.

At this time, while supplying the grinding water 64 from the opening 62, the grinding feed unit 32 grinds the rough grinding unit 44a downward. When the rough grinding wheel 60a comes into contact with the back surface 11b side of the workpiece 11, the contact region on the back surface 11b side is ground.

Here, the process returns to FIG. A square columnar support structure 30b is provided adjacent to one of the support structures 30a in the X-axis direction and behind the finish grinding region C. Similar to the support structure 30a, a grinding feed unit 32 is provided in front of the support structure 30b.

A finish grinding unit (grinding unit) 44b is connected to the grinding feed unit 32 of the support structure 30b. The finish grinding unit 44b, like the rough grinding unit 44a, also has a holding member 46, a spindle housing 48, a spindle 50, a third rotary drive source 52, and a wheel mount 54.

However, an annular finish grinding wheel 56b is mounted on the spindle 50 of the finish grinding unit 44b via a wheel mount 54. Immediately below the finish grinding wheel 56b corresponds to the above-mentioned finish grinding region C.

The finish grinding wheel 56b has a wheel base 58. Further, on the lower surface side of the wheel base 58 of the finish grinding unit 44b, a plurality of finish grinding wheels having an average particle size smaller than the average particle size of the abrasive grains of the rough grinding wheel 60a are arranged.

The plurality of finish grinding wheels are arranged in an annular shape along the circumference of the lower surface of the wheel base 58 in such a manner that a gap is provided between the adjacent finish grinding wheels. Further, a plurality of openings 62 are provided inside the plurality of finish grinding wheels along the circumference of the lower surface of the wheel base 58.

The wheel base 58, wheel mount 54, spindle 50, etc. of the finish grinding unit 44b are also provided with a flow path for supplying the grinding water 64 to the opening 62, and the grinding water is supplied to one end of the flow path. Unit 66 (see FIG. 3) is connected.

An unloading arm 68 having a disk-shaped pad at the tip for sucking and holding the workpiece 11 in a region in front of the loading / unloading region A and adjacent to the base end portion of the loading arm 16 in the X-axis direction. The base end portion of is provided.

A spinner cleaning unit 70 for cleaning and drying the workpiece 11 and the like is provided in front of the base end portion of the unloading arm 68. Between the spinner cleaning unit 70 and the cassette 10b, a foreign matter measuring device for measuring the amount of foreign matter adhering to the upper surface by imaging the upper surface side (that is, the back surface 11b side) of the workpiece 11 or the like. 72 is provided.

The foreign matter measuring device 72 is, for example, a camera, and has an objective lens and an image sensor (imaging element). The image captured by the foreign matter measuring device 72 is sent to the control unit 74. The control unit 74 performs, for example, binarization of the image to determine the presence or absence of foreign matter.

Specifically, the control unit 74 compares the pixel value of each pixel subjected to the binarization process with the threshold value, and when the pixel is equal to or greater than the threshold value (or less than or equal to the threshold value), a foreign object is placed at a position corresponding to the pixel. Is determined to be attached.

The control unit 74 may display the image after the binarization process on a display device (not shown). This makes it possible to provide visual information indicating whether or not foreign matter remains on the back surface 11b side. Further, the operator can determine whether or not the foreign matter is properly removed by the spinner cleaning unit 70, that is, whether or not the spinner cleaning unit 70 is abnormal, based on the image.

In addition to the foreign matter measuring device 72, the control unit 74 includes a transfer robot 6, a positioning table 12, a loading arm 16, a turntable 18, a chuck table 20, a grinding feed unit 32, a rough grinding unit 44a, a finish grinding unit 44b, and an unloading. It controls the operation of the arm 68, the spinner cleaning unit 70, and the like.

The control unit 74 is, for example, a processing device such as a processor represented by a CPU (Central Processing Unit) and a main memory such as a DRAM (Dynamic Random Access Memory), a SRAM (Static Random Access Memory), and a ROM (Read Only Memory). It is composed of a computer including a device and an auxiliary storage device such as a flash memory, a hard disk drive, and a solid state drive.

Software including a predetermined program is stored in the auxiliary storage device. The function of the control unit 74 is realized by operating the processing device or the like according to this software.

Next, the grinding chamber and the like of the grinding device 2 will be described with reference to FIGS. 1 and 3. First, the rough grinding chamber 76a in which the rough grinding wheel 56a is arranged will be described. As shown in FIG. 1, a metal prismatic cover member 78a is provided above the rough grinding region B.

The cover member 78a has a chuck table 20 arranged in the rough grinding region B, a wheel mount 54, and a top plate that covers above the rough grinding wheel 56a. A plurality of side plates are provided around the top plate so as to surround the top plate.

The cover member 78a forms a rough grinding chamber 76a that separates the rough grinding area B from the carry-in / carry-out area A and the finish grinding area C. Grinding debris 80 generated during the previous grinding is usually attached to the inner wall of the cover member 78a.

When grinding is performed again after a certain period of time has elapsed from the latest grinding, the grinding device 2 is idling (that is, warm-up operation). However, when idling, the rough grinding wheel 56a and the chuck table 20 are rotated while the grinding water 64 is supplied from the opening 62 of the rough grinding wheel 56a, so that the grinding water 64 is scattered in the rough grinding chamber 76a.

Due to the scattering of the grinding water 64, the grinding debris 80 adhering to the inner wall of the cover member 78a (particularly, the inner wall of the top plate) falls on the holding surface 20a of the chuck table 20 in a state of being mixed with the water droplets of the grinding water 64. Sometimes. Further, the grinding debris 80 adhering to the rough grinding wheel 56a itself may fall on the holding surface 20a together with the grinding water 64.

Therefore, in the present embodiment, as shown in FIGS. 2 and 3, idling is performed while the protective substrate 19 is held by the upper surface 26b of the porous plate 26. The outer diameter of the upper surface 26b of the porous plate 26 is smaller than the outer diameter of the protective substrate 19. Therefore, when idling, the entire upper surface 26b of the porous plate 26 is covered with the protective substrate 19.

As a result, even if the grinding debris 80 adhering to the inner wall of the cover member 78a or the rough grinding wheel 56a falls on the chuck table 20 together with the grinding water 64, the region covered with the protective substrate 19 (that is, the chuck table 20). At least a part of the upper surface of the surface) can be prevented from being contaminated. Therefore, the contamination of the chuck table 20 can be reduced.

A metal prismatic cover member 78b is provided above the finish grinding area C. The cover member 78b has a chuck table 20 arranged in the finish grinding area C, a wheel mount 54, and a top plate that covers the upper part of the finish grinding wheel 56b. A plurality of side plates are provided around the top plate so as to surround the top plate.

The cover member 78b forms a finish grinding chamber 76b that separates the finish grinding area C from the carry-in / carry-out area A and the rough grinding area B. Grinding debris 80 generated during the previous grinding is usually attached to the inner wall of the cover member 78b.

When idling, the entire upper surface 26b of the porous plate 26 of the chuck table 20 arranged in the finish grinding region C is covered with the protective substrate 19, so that the region covered with the protective substrate 19 can be prevented from being contaminated.

Next, a method of idling in the grinding device 2 will be described. FIG. 4 is a flow chart showing a procedure such as idling. First, a plate-shaped object holding step S10 for sucking and holding the protective substrate 19 on the plurality of chuck tables 20 is performed.

In S10, the transfer robot 6 conveys the protective substrate 19 (plate-like object) from the accommodating portion 14c to the positioning table 12, and then the loading arm 16 is arranged from the positioning table 12 in the loading / unloading area A of the chuck table 20. The protective substrate 19 is conveyed to the vehicle.

The loading arm 16 conveys the protective substrate 19 to the central portion of the chuck table 20. Then, by sucking and holding the protective substrate 19 on the chuck table 20, the protective substrate 19 is held on the upper surface 26b and the upper surface 28b (that is, at least a part of the upper surface of the chuck table 20).

After that, the turntable 18 is rotated about 120 degrees clockwise in the top view to move the chuck table 20 holding the protective substrate 19 to the rough grinding area B, and the chuck table arranged in the carry-in / carry-out area A. At 20, the protective substrate 19 is similarly sucked and held.

After S10, the turntable 18 is further rotated clockwise by approximately 120 degrees in the top view. As a result, the chuck table 20 holding the first protective substrate 19 is arranged below the cover member 78b, and the chuck table 20 holding the second protective substrate 19 is arranged below the cover member 78a. ..

Next, the grinding water 64 is supplied from the opening 62 of the rough grinding wheel 56a, and the rough grinding wheel 56a and the chuck table 20 arranged in the rough grinding region B are rotated in a predetermined direction. For example, the rough grinding wheel 56a and the chuck table 20 are rotated in the same direction, but they may be rotated in opposite directions.

Similarly, the grinding water 64 is supplied from the opening 62 of the finish grinding wheel 56b, and the finish grinding wheel 56b and the chuck table 20 arranged in the finish grinding area C are rotated in a predetermined direction (idling step S20). .. For example, the finish grinding wheel 56b and the chuck table 20 are rotated in the same direction, but may be rotated in opposite directions.

In S20, the state of the grinding device 2 is adjusted so that grinding can be performed with a predetermined accuracy by idling while supplying the grinding water 60 adjusted to a predetermined temperature (for example, 23 ° C.). The protective substrate 19 is not ground when idling.

In S20, even if the grinding debris 80 adhering to the inner walls of the cover members 78a and 78b falls on the chuck table 20 together with the grinding water 64, the region covered with the protective substrate 19 (that is, the upper surface of the chuck table 20). At least a part of) can be prevented from being contaminated. Therefore, the contamination of the chuck table 20 can be reduced.

After S20, the turntable 18 is rotated by approximately 240 degrees in the counterclockwise direction when viewed from above, and the chuck table 20 arranged in the finish grinding area C is moved to the carry-in / carry-out area A. At this time, the chuck table 20 arranged in the rough grinding area B moves to the finish grinding area C.

Then, the unloading arm 68 conveys the first protective substrate 19 from the chuck table 20 arranged in the carry-in / carry-out area A to the spinner cleaning unit 70. While cleaning the first protective substrate 19, the turntable 18 is rotated approximately 120 degrees clockwise in the top view to finish and hold the chuck table 20 that sucks and holds the second protective substrate 19 in the finishing grinding area. Move from C to the carry-in / carry-out area A.

Then, after the transfer robot 6 transfers the first protective substrate 19 from the spinner cleaning unit 70 to the cassette 10b, the unloading arm 68 moves the second protective substrate from the chuck table 20 to the spinner cleaning unit 70. 19 is transported. In this way, each protective substrate 19 is cleaned (plate-shaped object cleaning step S30).

While the protective substrate 19 after cleaning is being transferred from the spinner cleaning unit 70 to the cassette 10b using the transfer robot 6, the transfer robot 6 is stopped directly under the foreign matter measuring device 72 and protected by the foreign matter measuring device 72. The upper surface of the substrate 19 may be imaged. Thereby, it is possible to determine whether or not there is an abnormality in the spinner cleaning unit 70.

After all the protective substrates 19 are washed and conveyed to the cassette 10b, the workpiece 11 is sequentially carried from the cassette 10a to the chuck table 20. As a result, rough grinding, finish grinding, cleaning and the like on the back surface 11b side of the workpiece 11 are sequentially performed (fully automatic grinding step S40).

By the way, as a modification of the first embodiment, at least a part of the upper surface of the chuck table 20 may be covered with a plurality of workpieces 11 instead of the protective substrate 19. In this case, in the plate-shaped object holding step S10, the workpiece 11 is sequentially sucked and held by each of the two chuck tables 20.

After S10, the chuck table 20 holding the first workpiece 11 is arranged below the cover member 78b, and the chuck table 20 holding the second workpiece 11 is arranged below the cover member 78a. do. In this state, the idling step S20 is performed without grinding the workpiece 11.

In S20, even if the grinding debris 80 adhering to the inner walls of the cover members 78a and 78b falls on the chuck table 20 together with the grinding water 64, the region covered with the workpiece 11 (that is, the upper surface of the chuck table 20). At least a part of) can be prevented from being contaminated. Therefore, the contamination of the chuck table 20 can be reduced.

After S20, each workpiece 11 is sequentially cleaned by the spinner cleaning unit 70 (plate-shaped object cleaning step S30). After each of the workpieces 11 after cleaning is carried into the cassette 10b, the workpieces 11 are sequentially carried in from the cassette 10a to perform grinding, cleaning and the like (fully automatic grinding step S40).

Next, the second embodiment will be described. FIG. 5A is a partial cross-sectional side view of the protective substrate 19 and the like according to the second embodiment. The protective substrate 19 (plate-like object) of the second embodiment has a diameter larger than that of the workpiece 11.

Specifically, the protective substrate 19 has an outer diameter larger than the outer diameter of the upper surface 28b of the annular porous member 28 and smaller than the outer diameter of the upper surface 24d of the frame body 24. In other words, the outer diameter of the upper surface 28b is smaller than the outer diameter of the protective substrate 19.

By holding the protective substrate 19 on the chuck table 20, the entire upper surface 26b of the porous plate 26 and the upper surface 28b of the annular porous member 28 can be covered. Therefore, when idling, contamination of the upper surface 26b and the upper surface 28b (that is, at least a part of the upper surface of the chuck table 20) can be prevented. Therefore, the contamination of the chuck table 20 can be reduced.

Next, a third embodiment will be described. FIG. 5B is a partial cross-sectional side view of the protective substrate 19 and the like according to the third embodiment. The protective substrate 19 (plate-like object) of the third embodiment has a larger diameter than the protective substrate 19 of the second embodiment.

Specifically, the protective substrate 19 has an outer diameter larger than the outer diameter of the upper surface 24d of the frame body 24. In other words, the outer diameter of the upper surface 24d is smaller than the outer diameter of the protective substrate 19. By holding the protective substrate 19 on the chuck table 20, the entire upper surface 26b, upper surface 28b, and upper surface 24d can be covered. Therefore, when idling, it is possible to prevent contamination of the entire upper surface of the chuck table 20.

Next, a fourth embodiment will be described. FIG. 6 is a perspective view of the grinding device 2 according to the fourth embodiment. The accommodating portion 14c is located above the spinner cleaning unit 70, not above the positioning table 12. This point is different from that of the first embodiment.

Also in the fourth embodiment, by using the protective substrate 19, the area covered with the protective substrate 19 or the workpiece 11 is prevented from being contaminated during idling, as in the first to third embodiments. can. In addition, the structure, method, and the like according to the above-described embodiment can be appropriately modified and implemented as long as they do not deviate from the scope of the object of the present invention.

2: Grinding device 4: Base, 4a: Recess 6: Conveying robot 8a, 8b: Cassette mounting area 10a, 10b: Cassette 11: Work piece, 11a: Front surface, 11b: Back surface 12: Positioning table 13: Protective tape 14a: Leg, 14b: Mounting table, 14c: Accommodating part 16: Loading arm 18: Turntable 19: Protective substrate 20: Chuck table, 20a: Holding surface 22: Table base 22a: Second rotation drive source, 22b : Output shaft 24: Frame, 24a: Recessed, 24b, 24c: Flow path, 24d: Upper surface 26: Porous plate, 26a: Outer peripheral side surface, 26b: Upper surface 28: Circular porous member, 28a: Outer peripheral side surface, 28b: Upper surface 30a , 30b: Support structure 32: Grinding feed unit, 34: Z-axis guide rail, 36: Z-axis moving plate 38: Nut part, 40: Z-axis ball screw, 42: Z-axis pulse motor 44a: Rough grinding unit, 44b: Finishing Grinding unit 46: Holding member 48: Spindle housing 50: Spindle 52: Third rotary drive source 54: Wheel mount 56a: Rough grinding wheel, 56b: Finish grinding wheel 58: Wheel base 60a: Rough grinding grind 62: Opening 64 : Grinding water 66: Grinding water supply unit 68: Unloading arm 70: Spinner cleaning unit 72: Foreign matter measuring instrument 74: Control unit 76a: Rough grinding chamber 78a, 78b: Cover member 80: Grinding waste A: Carry-in / carry-out area B: Rough grinding area C: Finish grinding area

Claims (6)

A grinding device that grinds a work piece
With a chuck table that can rotate around a given axis of rotation,
A grinding unit having a spindle and an annular grinding wheel mounted on the lower end of the spindle, and rotating the grinding wheel while supplying grinding water from a grinding water supply port provided on the grinding wheel.
A cover member that covers the upper part of the chuck table and the grinding wheel, and
A plate-shaped material accommodating portion for accommodating a plate-shaped material for protecting at least a part of the upper surface of the chuck table, and a plate-shaped material accommodating portion.
A control unit for controlling the operation of the chuck table and the grinding unit is provided.
A grinding apparatus characterized in that, while holding the plate-like object on at least a part of the upper surface of the chuck table, the grinding water is supplied and idling is performed to rotate the grinding wheel and the chuck table. The chuck table is
With a disk-shaped porous plate
An annular porous member arranged so as to surround the outer circumference of the porous plate and having an average pore size smaller than that of the porous plate.
A frame body that surrounds the outer periphery of the annular porous member and supports the porous plate and the annular porous member is provided.
The first aspect of the present invention, wherein the outer diameter of the upper surface of the porous plate is smaller than the outer diameter of the plate-shaped material, and the entire upper surface of the porous plate is covered with the plate-shaped material when idling. Grinding device. The outer diameter of the upper surface of the annular porous member is smaller than the outer diameter of the plate-shaped object, and when idling, the entire upper surface of the porous plate and the annular porous member is covered with the plate-shaped object. The grinding apparatus according to claim 2. The outer diameter of the upper surface of the frame is smaller than the outer diameter of the plate, and when idling, the porous plate, the annular porous member, and the entire upper surface of the frame are covered with the plate. The grinding apparatus according to claim 2 or 3. The grinding apparatus according to any one of claims 1 to 4, wherein the plate-shaped material is made of a non-metallic material. It is a method of idling in a grinding machine.
A plate-like object holding step for holding a plate-like object on at least a part of the upper surface of the chuck table,
The grinding wheel of a grinding unit having a spindle and an annular grinding wheel mounted on the lower end of the spindle with the chuck table placed below the cover member after the plate-like object holding step. A method for performing idling in a grinding apparatus, which comprises supplying grinding water from a grinding water supply port provided in the above and an idling step for rotating the grinding wheel and the chuck table in a predetermined direction.

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