Grinding device, program, non-transitory recording medium, and grinding device control method

Abstract

To provide a grinding device which can prevent an operator from forgetting execution of self-grinding.SOLUTION: A grinding device includes: a control unit which has a processing device and a storage device, and controls a chuck table, a grinding unit, and a movement mechanism according to a program stored in the storage device; and an input device which inputs a command to the control unit. The program causes the control unit to practice a procedure of stopping an operation of the grinding device after the command of stopping an operation of the grinding device is inputted to the control unit from the input device, and a procedure of grinding a holding surface by a grinding wheel after the command of stopping an operation of the grinding device is inputted to the control unit from the input device and before the procedure of stopping the operation of the grinding device is completed.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a grinding device used when grinding a workpiece such as a wafer, a program used to control the grinding device, a non-transitory recording medium on which the program is stored, and a method for controlling the grinding device. [Background technology]

[0002] In order to realize small and lightweight device chips, there are increasing opportunities to thin wafers with devices such as integrated circuits on their front side. For example, the front side of the wafer is held by the holding surface of a chuck table, and the chuck table and a grinding wheel with a grinding stone containing abrasive grains fixed thereto are rotated relative to each other, and the grinding stone is pressed against the back side of the wafer while a liquid (grinding fluid) such as pure water is supplied, thereby grinding the wafer to thin it.

[0003] Incidentally, when grinding a workpiece such as a wafer using the above-described method, a process called self-grinding is performed in which the holding surface of the chuck table is ground (see, for example, Patent Document 1). In this self-grinding, the holding surface is ground with a grinding wheel (grinding stone) in the same way as the workpiece. Therefore, when the workpiece is held by the holding surface after self-grinding, the distance between the grinding wheel and the holding surface becomes approximately constant over the entire area where the workpiece and the grinding wheel contact each other, and the workpiece is ground so that its overall thickness is approximately constant. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-87104 Summary of the Invention [Problem to be solved by the invention]

[0005] In a chuck table used for grinding a workpiece, the suction force generated by the negative pressure from a suction source acts on the workpiece through minute pores in the holding surface, thereby holding the workpiece. However, as grinding of the workpiece progresses, the pores in the holding surface may become clogged with debris generated from the workpiece, reducing the force holding the workpiece. Therefore, the self-grinding process described above is performed at any time before the pores in the holding surface become clogged with debris, thereby removing the debris adhering to the holding surface.

[0006] However, this self-grinding is performed based on the operator's instructions and is not always performed at the appropriate time. For example, if the operator forgets to perform the self-grinding and the holes in the holding surface become clogged with debris, the workpiece will not be held securely by the chuck table, which will have a negative impact on the grinding of the workpiece.

[0007] SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a grinding device or the like that can prevent an operator from forgetting to perform self-grinding. [Means for solving the problem]

[0008] According to one aspect of the present invention, a grinding apparatus includes a chuck table having a holding surface for holding a workpiece and rotatable about a rotation axis intersecting the holding surface, a grinding unit having a spindle that can rotate about an axis with a grinding wheel attached to its tip, a movement mechanism that moves the chuck table and the grinding unit relatively in a direction intersecting the holding surface, a control unit having a processing device and a memory device and controlling the chuck table, the grinding unit, and the movement mechanism in accordance with a program stored in the memory device, and an input device that inputs commands to the control unit, the program being transmitted from the input device to the control unit. The grinding device is shut down. a procedure for stopping the operation of the grinding device after a command to stop the operation of the grinding device is input; The grinding device is shut down.After a command to stop the operation of the grinding device is input, and before the procedure for stopping the operation of the grinding device is completed, the control unit executes a procedure for moving the grinding unit and the chuck table relative to each other by the moving mechanism while the chuck table and the spindle are rotating, and grinding the holding surface with the grinding wheel.

[0009] According to another aspect of the present invention, there is provided a program for use in controlling a grinding apparatus, the program comprising: a chuck table having a holding surface for holding a workpiece and rotatable about a rotation axis intersecting the holding surface; a grinding unit having a spindle that can rotate about an axis with a grinding wheel attached to its tip; a movement mechanism that moves the chuck table and the grinding unit relatively in a direction intersecting the holding surface; a control unit having a processing device and a storage device, the control unit controlling the chuck table, the grinding unit, and the movement mechanism in accordance with a program stored in the storage device; and an input device for inputting commands to the control unit, the input device inputting commands to the control unit. The grinding device is shut down. a procedure for stopping the operation of the grinding device after a command to stop the operation of the grinding device is input; The grinding device is shut down. A program is provided that causes the control unit to execute a procedure in which, after a command to stop the operation of the grinding device is input, and before the procedure for stopping the operation of the grinding device is completed, the grinding unit and the chuck table are moved relative to each other by the moving mechanism while the chuck table and the spindle are rotating, and the holding surface is ground by the grinding wheel.

[0010] Preferably, the program transmits the command to the control unit from the input device. The grinding device is shut down. After a command to stop the operation of the grinding device is input, the program causes the control unit to execute a procedure for adjusting the angle between the rotation axis of the chuck table and the axis of the spindle before the procedure for grinding the holding surface with the grinding wheel is started. The grinding device is shut down.After a command to stop the operation of the grinding device is input, the program causes the control unit to execute a procedure for grinding the holding surface with the grinding wheel without causing the control unit to execute a procedure for replacing the grinding wheel attached to the spindle. Preferably, the program causes the control unit to execute a procedure for stopping the operation of the grinding device and a procedure for grinding the holding surface with the grinding wheel so that the procedure for grinding the holding surface with the grinding wheel is completed before the procedure for stopping the operation of the grinding device is completed.

[0011] According to yet another aspect of the present invention, there is provided a non-transitory storage medium on which the program is stored.

[0012] According to yet another aspect of the present invention, there is provided a method for controlling a grinding apparatus, the method comprising: a chuck table having a holding surface for holding a workpiece and rotatable about a rotation axis intersecting the holding surface; a grinding unit having a spindle that can rotate about an axis with a grinding wheel attached to its tip; a movement mechanism that moves the chuck table and the grinding unit relatively in a direction intersecting the holding surface; a control unit having a processing device and a storage device and that controls the chuck table, the grinding unit, and the movement mechanism in accordance with a program stored in the storage device; and an input device that inputs commands to the control unit, the input device The grinding device is shut down. a step of inputting a command to stop the operation of the grinding device, and inputting the command from the input device to the control unit; The grinding device is shut down. a step of stopping the operation of the grinding device after a command to stop the operation of the grinding device is input; The grinding device is shut down. After a command to stop the operation of the grinding device is input, and before the step of stopping the operation of the grinding device is completed, the grinding unit and the chuck table are moved relative to each other by the moving mechanism while the chuck table and the spindle are rotating, and the holding surface is ground by the grinding wheel.

[0013] Preferably, the input device is connected to the control unit. The grinding device is shut down. The method further includes a step of adjusting an angle between the rotation axis of the chuck table and the axis of the spindle after a command to stop the operation of the grinding device is input and before the step of grinding the holding surface with the grinding wheel is started. The grinding device is shut down. After a command to stop the operation of the grinding device is input, the step of grinding the holding surface with the grinding wheel is performed without performing the step of replacing the grinding wheel attached to the spindle, and preferably, the step of grinding the holding surface with the grinding wheel is completed before the step of stopping the operation of the grinding device is completed. [Effects of the Invention]

[0014] In the grinding device, program, and control method for a grinding device according to the present invention, the control unit executes the following steps: a procedure for stopping the operation of the grinding device after an instruction to stop the operation of the grinding device is input from an input device to the control unit; and a procedure for grinding the holding surface with a grinding wheel after an instruction to stop the operation of the grinding device is input from the input device to the control unit and before the procedure for stopping the operation of the grinding device is completed.

[0015] In other words, when the grinding device is shut down, self-grinding, which grinds the holding surface with the grinding wheel, is always performed. Therefore, the grinding device, program, and grinding device control method of the present invention prevent the operator from forgetting to perform self-grinding. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is a perspective view schematically showing a grinding device. [Figure 2] FIG. 2 is a functional block diagram that schematically shows the functional structure of the control unit. [Figure 3] FIG. 3 is a flowchart showing the flow of processing when shutting down the grinding apparatus. [Figure 4] FIG. 4 is a cross-sectional view schematically showing how the holding surface of the chuck table is ground. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a perspective view that schematically shows a grinding apparatus 2 of this embodiment. In Fig. 1, some of the elements that make up the grinding apparatus 2 are expressed as functional blocks. In addition, the X-axis direction (front-rear direction), Y-axis direction (left-right direction), and Z-axis direction (vertical direction) used in the following description are perpendicular to one another.

[0018] As shown in Fig. 1, the grinding apparatus 2 includes a base 4 that supports various elements that make up the grinding apparatus 2. A recessed storage section 4a, whose upper end opens to the upper surface of the base 4, is provided at the front end of the upper surface of the base 4, and a first transport mechanism 6 used to transport a plate-shaped workpiece 11 is housed within this storage section 4a. The first transport mechanism 6 is typically a robot arm with multiple joints, and is capable of not only transporting the workpiece 11 but also turning the workpiece 11 upside down.

[0019] The workpiece 11 is, for example, a disk-shaped wafer made of a semiconductor material such as silicon. That is, the workpiece 11 has a circular front surface 11a and a circular back surface 11b opposite the front surface 11a. The front surface 11a side of the workpiece 11 is divided into a plurality of small regions by a plurality of intersecting streets (planned division lines), and a device such as an integrated circuit (IC) is formed in each small region.

[0020] The grinding device 2 of this embodiment is used, for example, when grinding the back surface 11b side of the workpiece 11. When grinding the back surface 11b side of the workpiece 11, it is desirable to attach a protective member made of a material such as resin to the front surface 11a side of the workpiece 11. By attaching the protective member to the front surface 11a side of the workpiece 11, the impact applied to the front surface 11a side when grinding the back surface 11b side is alleviated, and devices and the like of the workpiece 11 are protected.

[0021] In addition, in this embodiment, a disk-shaped wafer made of a semiconductor material such as silicon is used as the workpiece 11, but the material, shape, structure, size, etc. of the workpiece 11 are not limited to this embodiment. For example, a substrate made of other semiconductors, ceramics, resin, metal, etc. may be used as the workpiece 11. Similarly, the type, number, shape, structure, size, arrangement, etc. of the devices are not limited to the above embodiment. The workpiece 11 does not necessarily have to have any devices formed thereon.

[0022] 1, cassette tables 10a and 10b are provided in front of the storage unit 4a, on which cassettes 8a and 8b, each capable of storing a plurality of workpieces 11, are placed. A position adjustment mechanism 12 for adjusting the position of the workpieces 11 is provided diagonally behind the storage unit 4a. The position adjustment mechanism 12 includes a disk-shaped position adjustment table and a plurality of pins arranged around the periphery of the position adjustment table.

[0023] By moving the pins in the radial direction of the position adjustment table, for example, the center of the workpiece 11 carried out from the cassette 8a by the first transport mechanism 6 and placed on the position adjustment table is aligned to a predetermined position in the X-axis direction and the Y-axis direction. The workpiece 11 is placed on the position adjustment table so that its surface to be ground (in this embodiment, the back surface 11b) is exposed upward.

[0024] A second transport mechanism 14 that holds and transports the workpiece 11 rearward is provided on the side of the position adjustment mechanism 12. The second transport mechanism 14 includes, for example, an arm and a holding pad that is connected to the tip of the arm and can hold the top surface (surface to be ground) of the workpiece 11 by suction, and transports the workpiece 11, whose position has been adjusted by the position adjustment mechanism 12, rearward by rotating the holding pad with the arm.

[0025] A turntable 16 is provided behind the second transport mechanism 14. The turntable 16 is connected to a motor (not shown) or the like, and rotates around a rotation axis that is roughly parallel to the Z-axis direction by the power of the motor or the like. Three sets of cylindrical (disk-shaped) table bases 18 are provided on the upper surface of the turntable 16 at roughly equal angular intervals along the circumferential direction of the turntable 16. However, the number of table bases 18 is not limited to this.

[0026] Each table base 18 is connected to a motor (not shown) or the like, and rotates around a rotation axis that is roughly parallel to the Z-axis direction or a rotation axis that is slightly tilted with respect to the Z-axis direction by the power of this motor, etc. Each table base 18 is supported on the turntable 16 via an angle adjustment mechanism (not shown), and the angle of the rotation axis of each table base 18 is adjusted by this angle adjustment mechanism.

[0027] A disk-shaped chuck table 20 used to hold the workpiece 11 is fixed to the upper end of each table base 18 with bolts or the like. Each chuck table 20 includes a disk-shaped frame 20a (see FIG. 4) made of a material such as ceramics. A recess is provided in the upper part of the frame 20a, the upper end of which is circularly open to the upper surface of the frame 20a. A porous disk-shaped holding plate 20b (see FIG. 4) made of a material such as ceramics is fixed to this recess.

[0028] The upper surface of the holding plate 20b is configured, for example, in a shape corresponding to the side surface of a cone, and functions as a holding surface for holding the workpiece 11. The difference in height (height difference) between the center of the upper surface of the holding plate 20b, which corresponds to the apex of the cone, and the outer periphery of the upper surface of the holding plate 20b is approximately 10 μm to 30 μm.

[0029] The lower surface of the holding plate 20b is connected to a suction source (not shown) such as an ejector via a flow path provided inside the frame 20a or a valve (not shown) arranged outside the frame 20a. Therefore, when the valve is opened and negative pressure from the suction source is applied while the workpiece 11 or the like is in contact with the upper surface of the holding plate 20b, the workpiece 11 is sucked by the chuck table 20. In other words, the workpiece 11 is held by the holding surface of the chuck table 20.

[0030] With the chuck table 20 fixed to the table base 18, the turntable 16 rotates, for example, in the direction of the arrow in Fig. 1 and in the direction opposite to the arrow. As the turntable 16 rotates, the table base 18 and the chuck table 20 move in the circumferential direction of the turntable 16.

[0031] The turntable 16 moves the table base 18 and the chuck table 20, for example, in the order of a load-in / load-out area adjacent to the second transport mechanism 14, a rough grinding area behind the load-in / load-out area, a finish grinding area to the side of the rough grinding area, and then the load-in / load-out area. The second transport mechanism 14 transports the workpiece 11 held by a holding pad from the position adjustment table of the position adjustment mechanism 12 to the chuck table 20 arranged in the load-in / load-out area.

[0032] 1, columnar support structures 30 are provided behind the rough grinding area and the finish grinding area (i.e., behind the turntable 16), respectively. A Z-axis movement mechanism 32 is provided on the front side of each support structure 30. Each Z-axis movement mechanism 32 has a pair of guide rails 34 that are generally parallel to the Z-axis direction, and a movement plate 36 is attached to the guide rails 34 in a slidable manner.

[0033] A nut portion (not shown) constituting a ball screw is provided on the rear surface side (back surface side) of each moving plate 36, and a screw shaft 38 that is generally parallel to the guide rail 34 is rotatably connected to this nut portion. A motor 40 or the like is connected to one end of the screw shaft 38. By rotating the screw shaft 38 by the motor 40 or the like, the moving plate 36 moves along the guide rail 34 (in the Z-axis direction).

[0034] A fixture 42 is provided on the front surface (surface) of each moving plate 36. Each fixture 42 supports a grinding unit 44 that can grind the workpiece 11. Each grinding unit 44 has a spindle housing 46 fixed to the fixture 42. Each spindle housing 46 accommodates a spindle 48 whose rotation axis is parallel to the Z-axis direction or slightly inclined with respect to the Z-axis direction, in a manner that the spindle 48 can rotate about its axis.

[0035] The lower end of each spindle 48 is exposed from the lower end surface of the spindle housing 46, and a disk-shaped mount 50 is fixed to this lower end. For example, the outer edge of each mount 50 is provided with a plurality of holes (not shown) that penetrate the mount 50 in the thickness direction, and a bolt 52 or the like is inserted into each hole.

[0036] A grinding wheel 54 for rough grinding is attached to the underside of the mount 50 of the grinding unit 44 on the rough grinding area side with bolts 52. In other words, the grinding wheel 54 for rough grinding is attached to the spindle 48 on the rough grinding area side. Furthermore, a motor (not shown) and the like connected to the upper end side of the spindle 48 are housed in the spindle housing 46 of the grinding unit 44 on the rough grinding area side. The grinding wheel 54 for rough grinding rotates together with the spindle 48 by the power of this motor and the like.

[0037] On the other hand, a grinding wheel 54 for finish grinding is attached with bolts 52 to the underside of the mount 50 of the grinding unit 44 on the finish grinding area side. In other words, the grinding wheel 54 for finish grinding is attached to the spindle 48 on the finish grinding area side. Furthermore, a motor (not shown) and the like connected to the upper end side of the spindle 48 are housed in the spindle housing 46 of the grinding unit 44 on the finish grinding area side. The grinding wheel 54 for finish grinding rotates together with the spindle 48 by the power of this motor and the like.

[0038] Each grinding wheel 54 includes an annular wheel base 54a (see FIG. 4) made of metal such as stainless steel or aluminum. A plurality of grinding stones 54b (see FIG. 4), each made of abrasive grains such as diamond dispersed in a binder such as vitrified or resinoid, are fixed to the underside of the wheel base 54a along the circumferential direction of the wheel base 54a.

[0039] The average particle size of the abrasive grains contained in the grinding stone 54b of the grinding wheel 54 for finish grinding is smaller than the average particle size of the abrasive grains contained in the grinding stone 54b of the grinding wheel 54 for rough grinding. This allows for the realization of a grinding wheel 54 suitable for rough grinding and a grinding wheel 54 suitable for finish grinding. The specific size of the abrasive grains is appropriately set depending on the quality required of the workpiece 11 after grinding, etc.

[0040] A nozzle 56 capable of supplying a liquid (grinding fluid) 21 (see FIG. 4) such as pure water to the contact area between the workpiece 11 and the grinding stone 54b is disposed near the grinding wheel 54. Instead of or together with the nozzle 56, a liquid supply port used for supplying a liquid may be provided on the grinding wheel 54 or the like.

[0041] The workpiece 11 held on the chuck table 20 in the rough grinding area has its upper surface ground by the grinding unit 44 on the rough grinding area side. The workpiece 11 held on the chuck table 20 in the finish grinding area has its upper surface ground by the grinding unit 44 on the finish grinding area side.

[0042] That is, the chuck table 20 holding the workpiece 11 moves in the order of the carry-in / carry-out area, the rough grinding area, and the finish grinding area, thereby successively performing rough grinding and the finish grinding after the rough grinding of the workpiece 11. When the finish grinding of the workpiece 11 is completed, the chuck table 20 in the finish grinding area is again positioned in the carry-in / carry-out area.

[0043] A third transport mechanism 58 that holds and transports the ground workpiece 11 forward is provided in front of the loading / unloading area and to the side of the second transport mechanism 14. The third transport mechanism 58 includes a holding pad that holds the top surface of the workpiece 11 by suction, and an arm connected to this holding pad, and by rotating the holding pad with the arm, the ground workpiece 11 is transported forward from the chuck table 20 in the loading / unloading area.

[0044] A cleaning unit 60 is provided on the side of the third transport mechanism 58 to clean the workpiece 11 carried out by the third transport mechanism 58. The cleaning unit 60 includes, for example, a spinner table that rotates while holding the lower surface of the workpiece 11, and a cleaning nozzle that sprays a cleaning fluid onto the upper surface of the workpiece 11 held by the spinner table.

[0045] The cleaning fluid used in the cleaning unit 60 is typically a mixed fluid (two-fluid) of water and air. Of course, water not mixed with air may also be used as the cleaning fluid. The workpiece 11 cleaned in the cleaning unit 60 is transported by the first transport mechanism 6 and stored in, for example, a cassette 8b.

[0046] A control unit 62 is connected to each element of the grinding apparatus 2. This control unit 62 is configured by a computer including, for example, a processing device 62a and a storage device 62b, and controls the operation of each element of the grinding apparatus 2 described above, including the chuck table 20, the Z-axis moving mechanism 32, and the grinding unit 44, so that the workpiece 11 is properly ground.

[0047] The processing device 62a is typically a CPU (Central Processing Unit) and performs various processes required to control the above-mentioned elements. The storage device 62b includes, for example, a main storage device such as a DRAM (Dynamic Random Access Memory) and an auxiliary storage device such as a hard disk drive or flash memory. The functions of this control unit 62 are realized, for example, by the processing device 62a operating in accordance with software such as a program stored in the storage device 62b.

[0048] An input device 64 is connected to the control unit 62. The input device 64 is, for example, a touch panel, and is used by an operator to input commands to the control unit 62. This touch panel also serves as a display device that displays information output from the control unit 62. Note that a keyboard, a mouse, or the like may also be used as the input device 64.

[0049] In the grinding device 2 configured in this manner, when the device is shut down to stop operation, self-grinding is performed in which the holding surface of the chuck table 20 is ground by the grinding wheel 54. For example, a program for causing the control unit 62 to execute the necessary procedures is recorded in part of the storage device 62b, which is also a non-transitory recording medium that can be read by a computer or the like, and the control unit 62 controls the shutdown in accordance with this program.

[0050] 2 is a functional block diagram showing a functional structure of the control unit 62 implemented by the program of this embodiment. For ease of explanation, an input device 64 connected to the control unit 62 is also shown in FIG. 2. As shown in FIG. 2, the control unit 62 includes an input determination unit 66 that determines an input from the input device 64.

[0051] For example, when an operator inputs a shutdown command (a command to stop the operation of the grinding device 2) from the input device 64, the input determination unit 66 notifies the shutdown control unit 68 of the start of the shutdown procedure. The shutdown control unit 68 executes the shutdown procedure in accordance with the notification from the input determination unit 66.

[0052] For example, if the operating mode at the time of shutdown is set to "self-grind at shutdown" which performs self-grinding, the shutdown control unit 68 notifies the self-grind control unit 70 of the start of the self-grinding procedure when starting the shutdown procedure. The self-grind control unit 70 executes the self-grinding procedure in accordance with the notification from the shutdown control unit 68.

[0053] The control unit 62 further includes an operation mode setting unit 72 that sets the operation mode at the time of shutdown. For example, when an operation mode selected by the operator is input from the input device 64 to the input determination unit 66, the input determination unit 66 notifies the operation mode input from the input device 64 to the operation mode setting unit 72, and the operation mode setting unit 72 sets the operation mode notified from the input determination unit 66 as the operation mode at the time of shutdown. In addition to the above-mentioned "self-grind at shutdown," the operation modes at the time of shutdown include "normal shutdown," which does not perform self-grind at shutdown, etc.

[0054] The shutdown control unit 68 includes, for example, a power control unit 68a that controls the supply of power and a storage control unit 68b that controls the storage of information. When the input determination unit 66 notifies the shutdown control unit 68 of the start of the shutdown procedure, the storage control unit 68b executes a procedure for storing information that needs to be saved at the time of shutdown in the storage device 62b. For example, when the procedure for storing necessary information in the storage device 62b and other procedures necessary for shutdown are completed, the power control unit 68a executes a procedure for cutting off the supply of power to each element.

[0055] The self-grinding control unit 70 includes, for example, a wheel change control unit 70a that controls the change of the grinding wheel 54, and an angle adjustment unit 70b that adjusts the angle of the rotation axis of the chuck table 20 (the rotation axis of the table base 18). When starting the self-grinding procedure, the wheel change control unit 70a executes, as necessary, a procedure for changing the grinding wheel 54 from one suitable for grinding the workpiece 11 to one suitable for self-grinding (a procedure for changing the grinding wheel 54). Specifically, for example, the wheel change control unit 70a displays on a display device information and the like required to notify an operator that the grinding wheel 54 needs to be changed.

[0056] When starting the self-grinding procedure, the angle adjustment unit 70b executes a procedure to adjust the angle of the rotation axis of the chuck table 20 to a predetermined angle suitable for self-grinding. Specifically, for example, the angle adjustment unit 70b adjusts the angle of the rotation axis of the table base 18 using the angle adjustment mechanism described above. Note that the angle adjustment unit 70b may execute a procedure to adjust the angle of the axis of the spindle 48 instead of or in addition to the angle of the rotation axis of the chuck table 20.

[0057] 3 is a flowchart showing the flow of processing when shutting down the grinding apparatus 2. First, when the input device 64 inputs a shutdown command to the control unit 62 (step ST11), the input determination section 66 of the control unit 62 notifies the shutdown control section 68 of the start of shutdown.

[0058] The shutdown control unit 68, which has received notification from the input determination unit 66 that the shutdown procedure has begun, begins the shutdown procedure (step ST12). Specifically, for example, the storage control unit 68b begins a procedure for storing information that needs to be saved at the time of shutdown in the storage device 62b. Note that at this stage, the power control unit 68a does not begin a procedure for cutting off the supply of power to each element.

[0059] Furthermore, upon receiving notification of the start of the shutdown procedure from the input determination unit 66, the shutdown control unit 68 determines whether the operation mode set by the operation mode setting unit 72 is "shutdown self-grind," which performs self-grinding at the time of shutdown (step ST13). Note that, although Fig. 3 shows a flow in which the operation mode is determined after the shutdown procedure has started, the shutdown procedure may be started simultaneously with or after the operation mode is determined.

[0060] When "self-grind at end" is set as the operation mode (YES in step ST13), the shutdown control unit 68 notifies the self-grind control unit 70 of the start of the self-grind procedure. Upon receiving the notification of the start of the self-grind procedure from the shutdown control unit 68, the self-grind control unit 70 starts the self-grind procedure, for example, to grind the holding surface of the chuck table 20 with the grinding wheel 54 for finish grinding.

[0061] Specifically, for example, the angle adjustment unit 70b starts a procedure for adjusting the angle of the rotation axis of each chuck table 20 to a predetermined angle suitable for self-grinding (step ST14). That is, when each chuck table 20 is positioned in the finish grinding area, the angle adjustment unit 70b adjusts the angle between the rotation axis of that chuck table 20 and the axis of the spindle 48 to which the grinding wheel 54 for finish grinding is attached to a predetermined angle suitable for self-grinding.

[0062] Such an adjustment is necessary because, in general, the magnitude of the load applied when rotating the chuck table 20 or the grinding wheel 54 differs between grinding the workpiece 11 and grinding the holding surface of the chuck table 20. Note that if there is no substantial difference in the magnitude of the load during rotation, this angle adjustment may be omitted.

[0063] Once adjustment of the angle between the rotation axis of each chuck table 20 and the axis of the spindle 48 is complete, the self-grind control unit 70 starts the procedure of grinding the holding surface of the chuck table 20 with the grinding wheel 54 (step ST15). Figure 4 is a cross-sectional view that schematically shows how the holding surface of the chuck table 20 is ground. Specifically, first, the self-grind control unit 70 rotates each chuck table 20 around a rotation axis that intersects with the holding surface, and rotates the spindle 48, to which the grinding wheel 54 for finish grinding is attached, around its axis.

[0064] Next, with the chuck table 20 and the spindle 48 rotating, the self-grind control unit 70 causes the Z-axis movement mechanism 32 to lower the grinding wheel 54 for finish grinding while supplying the liquid 21 from the nozzle 56. In other words, the self-grind control unit 70 causes the Z-axis movement mechanism 32 to relatively move the chuck table 20 in the finish grinding area and the grinding unit 44 for finish grinding along the Z-axis direction that intersects with the holding surface of the chuck table 20.

[0065] As a result, the grinding stone 54b of the grinding wheel 54 for finish grinding comes into contact with the holding surface of the chuck table 20 in the finish grinding region, grinding the holding surface of the chuck table 20. The grinding amount (grinding thickness) of the holding surface is set arbitrarily within a range of, for example, 10 μm to 50 μm. However, the grinding amount of the holding surface is not limited to this range.

[0066] When grinding of the holding surfaces of the chuck table 20 in the finish grinding area is completed, the self-grinding control unit 70 rotates the turntable 16 to move another chuck table 20 to the finish grinding area, and similarly grinds the holding surfaces of this other chuck table 20. Rotation of the turntable 16 and grinding of the holding surfaces of the chuck tables 20 are alternately performed, and when the holding surfaces of all the chuck tables 20 have been ground, the self-grinding procedure is completed.

[0067] In the self-grinding procedure performed during this shutdown, it is desirable that the wheel change control unit 70a not execute the procedure for changing the grinding wheel 54. By not executing the procedure for changing the grinding wheel 54, which requires operator work, it is possible to more reliably prevent the operator from forgetting to execute self-grinding. In this case, however, the grinding wheel 54 needs to be configured so that it can grind both the workpiece 11 and the chuck table 20.

[0068] Of course, in the self-grinding procedure performed during shutdown, the wheel change control unit 70a may execute the procedure for replacing the grinding wheel 54. Furthermore, in general self-grinding procedures other than the self-grinding performed during shutdown, the wheel change control unit 70a may execute the procedure for replacing the grinding wheel 54.

[0069] When all procedures necessary for shutdown, including the self-grinding procedure, are completed, the power control unit 68a of the shutdown control unit 68 starts a procedure to cut off the supply of power to each element in order to complete the shutdown procedure (step ST16). When the supply of power to each element is cut off, all procedures to stop the operation of the grinding device 2 are completed, and the grinding device 2 enters a shut-down state.

[0070] As described above, according to the grinding apparatus 2, program, and grinding apparatus control method of this embodiment, when a predetermined operating mode is set, the control unit 62 executes the following steps: a procedure for stopping the operation of the grinding apparatus 2 after a command to stop the operation of the grinding apparatus 2 is input from the input device 64 to the control unit 62; and a procedure for grinding the holding surface with the grinding wheel 54 after a command to stop the operation of the grinding apparatus 2 is input from the input device 64 to the control unit 62 before the procedure for stopping the operation of the grinding apparatus 2 is completed.

[0071] In other words, when the grinding device 2 is shut down to stop operation, self-grinding, which grinds the holding surface with the grinding wheel 54, is always performed. Therefore, the grinding device 2, program, and grinding device control method according to this embodiment prevent the operator from forgetting to perform self-grinding. Furthermore, the grinding device 2, program, and grinding device control method according to this embodiment perform self-grinding during shutdown, which does not contribute to grinding of the workpiece 11, so productivity does not decrease due to self-grinding.

[0072] The present invention is not limited to the above-described embodiment and can be practiced with various modifications. For example, in the above-described embodiment, a self-grinding procedure is performed in which the holding surface of the chuck table 20 is ground with the grinding wheel 54 for finish grinding, but a self-grinding procedure in which the holding surface of the chuck table 20 is ground with the grinding wheel 54 for rough grinding may also be performed.

[0073] Furthermore, in the above-described embodiment, the program for executing the grinding device control method is recorded in the storage device 62b in the control unit 62, but this program may be recorded, for example, on any non-transitory recording medium that can be read by a computer, etc. For example, this program may be recorded on an optical disc such as a CD (Compact Disc) that can be distributed at low cost.

[0074] In addition, the structures, methods, etc. according to the above-described embodiments and modifications may be modified as appropriate without departing from the scope of the present invention. [Explanation of symbols]

[0075] 2: Grinding equipment 4: Base 4a: Storage section 6: First transport mechanism 8a: Cassette 8b: Cassette 10a: Cassette table 10b: Cassette table 12:Position adjustment mechanism 14: Second transport mechanism 16: Turntable 18: Table base 20: Chuck table 20a: Frame 20b: Holding plate 30:Support structure 32:Z-axis movement mechanism 34: Guide rail 36: Moving plate 38: Screw shaft 40: Motor 42: Fixture 44: Grinding unit 46: Spindle housing 48: Spindle 50: Mount 52: Bolt 54: Grinding wheel 54a: Wheel base 54b: Grinding wheel 56: Nozzle 58: Third transport mechanism 60: Cleaning unit 62: Control unit 62a: Processing device 62b: Storage device 64: Input device 66: Input judgment unit 68: Shutdown control section 68a: Power control section 68b: Memory control unit 70: Self-grind control unit 70a: Wheel change control section 70b: Angle adjustment section 72: Operation mode setting section 11: Workpiece 11a: Surface 11b: Back side 21: Liquid (grinding fluid)

Claims

1. A grinding device comprising: a chuck table having a holding surface for holding a workpiece and rotatable about a rotation axis intersecting the holding surface; a grinding unit having a spindle that can rotate around an axis with a grinding wheel attached to the tip thereof; a movement mechanism that moves the chuck table and the grinding unit relatively in a direction intersecting the holding surface; a control unit having a processing device and a storage device, and controlling the chuck table, the grinding unit, and the moving mechanism in accordance with a program stored in the storage device; an input device for inputting commands to the control unit; The program a step of stopping the operation of the grinding device after a command to stop the operation of the grinding device is input from the input device to the control unit so that the grinding device is shut down; a step of grinding the holding surface with the grinding wheel by moving the grinding unit and the chuck table relative to each other by the moving mechanism while the chuck table and the spindle are rotating, after a command to stop the operation of the grinding device so that the grinding device is shut down is input from the input device to the control unit, and before the step of stopping the operation of the grinding device is completed.

2. The program 2. The grinding apparatus according to claim 1, wherein after a command to stop operation of the grinding apparatus so as to shut down the grinding apparatus is input from the input device to the control unit, the control unit executes a procedure of adjusting the angle formed between the rotation axis of the chuck table and the axis of the spindle before a procedure of grinding the holding surface with the grinding wheel is started.

3. The program 3. The grinding device according to claim 1, wherein after a command to stop operation of the grinding device so that the grinding device is shut down is input from the input device to the control unit, the control unit executes a procedure for grinding the holding surface with the grinding wheel without executing a procedure for replacing the grinding wheel attached to the spindle.

4. The program 4. A grinding device according to claim 1, wherein the control unit executes a procedure for stopping the operation of the grinding device and a procedure for grinding the holding surface with the grinding wheel so that the procedure for grinding the holding surface with the grinding wheel is completed before the procedure for stopping the operation of the grinding device is completed.

5. a chuck table having a holding surface for holding a workpiece and rotatable about a rotation axis intersecting the holding surface; a grinding unit having a spindle that can rotate around an axis with a grinding wheel attached to the tip thereof; a movement mechanism that moves the chuck table and the grinding unit relatively in a direction intersecting the holding surface; a control unit having a processing device and a storage device, and controlling the chuck table, the grinding unit, and the moving mechanism in accordance with a program stored in the storage device; an input device for inputting commands to the control unit; and a program used to control a grinding machine comprising the program, a step of stopping the operation of the grinding device after a command to stop the operation of the grinding device is input from the input device to the control unit so that the grinding device is shut down; a program that causes the control unit to execute a procedure in which, after a command to stop operation of the grinding device so that the grinding device is shut down is input from the input device to the control unit, and before the procedure for stopping the operation of the grinding device is completed, the grinding unit and the chuck table are moved relative to each other by the moving mechanism while the chuck table and the spindle are rotating, and the holding surface is ground by the grinding wheel.

6. 6. The program according to claim 5, which causes the control unit to execute a procedure for adjusting the angle between the rotation axis of the chuck table and the axis of the spindle before starting a procedure for grinding the holding surface with the grinding wheel, after a command to stop operation of the grinding device so that the grinding device is shut down is input from the input device to the control unit.

7. 7. The program according to claim 5 or 6, which causes the control unit to execute a procedure for grinding the holding surface with the grinding wheel without causing the control unit to execute a procedure for replacing the grinding wheel attached to the spindle after a command to stop operation of the grinding device so that the grinding device is shut down is input from the input device to the control unit.

8. A program as described in any one of claims 5 to 7, which causes the control unit to execute a procedure for stopping the operation of the grinding device and a procedure for grinding the holding surface with the grinding wheel so that the procedure for grinding the holding surface with the grinding wheel is completed before the procedure for stopping the operation of the grinding device is completed.

9. A non-transitory recording medium storing the program according to any one of claims 5 to 8.

10. a chuck table having a holding surface for holding a workpiece and rotatable about a rotation axis intersecting the holding surface; a grinding unit having a spindle that can rotate around an axis with a grinding wheel attached to the tip thereof; a movement mechanism that moves the chuck table and the grinding unit relatively in a direction intersecting the holding surface; a control unit having a processing device and a storage device, and controlling the chuck table, the grinding unit, and the moving mechanism in accordance with a program stored in the storage device; an input device for inputting a command to the control unit, the input device inputting a command to the control unit to stop operation of the grinding device so that the grinding device is shut down; a step of stopping the operation of the grinding device after a command to stop the operation of the grinding device is input from the input device to the control unit so that the grinding device is shut down; a step of grinding the holding surface with the grinding wheel by moving the grinding unit and the chuck table relative to each other using the moving mechanism while the chuck table and the spindle are rotating, after a command to stop operation of the grinding device is input from the input device to the control unit so that the grinding device is shut down, and before the step of stopping the operation of the grinding device is completed.

11. 11. The method for controlling a grinding apparatus according to claim 10, further comprising the step of adjusting an angle formed between the rotation axis of the chuck table and the axis of the spindle before starting the step of grinding the holding surface with the grinding wheel, after a command to stop operation of the grinding apparatus is input from the input device to the control unit so that the grinding apparatus is shut down.

12. 12. A method for controlling a grinding apparatus according to claim 10 or 11, wherein after a command to stop operation of the grinding apparatus so that the grinding apparatus is shut down is input from the input device to the control unit, a step of grinding the holding surface with the grinding wheel is performed without performing a step of replacing the grinding wheel attached to the spindle.

13. 13. The method for controlling a grinding apparatus according to claim 10, wherein the step of grinding the holding surface with the grinding wheel is completed before the step of stopping the operation of the grinding apparatus is completed.

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