Processing device

Abstract

To reduce power consumption while balancing with processing device throughput.SOLUTION: A grinding apparatus 1 includes a chuck table 40, a grinding mechanism 80 that processes a workpiece held on the chuck table 40, and a movement mechanism that relatively moves the chuck table 40 and the grinding mechanism 80. The grinding apparatus 1 includes: servo motors that drive the chuck table 40, the grinding mechanism 80, and the movement mechanism, respectively; a motor driver 120 that operates the servo motors; a switch 110 that turns on / off power supplied to the motor driver 120; a processing condition setting unit 101 that sets processing conditions; a period calculation unit 102 that calculates drive periods of the servo motors on the basis of the processing conditions; a motor selection unit 103 that selects a servo motor that is not in operation on the basis of the drive period; and a switch control unit 104 that turns off the power to the motor driver 120 that operates the selected servo motor.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] There is known a processing device equipped with a servo motor that processes workpieces such as semiconductor wafers (see, for example, Patent Document 1). A servo system using such a servo motor is composed of a servo motor, a driver, and a controller, and the driver precisely controls the servo motor based on commands from the controller and feedback signals from the encoder of the servo motor.

[0003] On the other hand, in a servo system, power is supplied to the driver even when the servo motor is not being driven, so power consumption is high. In particular, when a servo system is used in a grinding machine with a long grinding time, such as that described in Patent Document 2, the standby time becomes long, and the power consumed by each driver while it is on standby increases relatively.

[0004] A technique related to such a problem is described, for example, in Patent Document 3. The technique describes a technique for reducing power consumption by slowing down the operating clock of the CPU in the servo amplifier (driver). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-091035 [Patent Document 2] Japanese Patent Application Laid-Open No. 2006-237333 [Patent Document 3] Japanese Patent Application Laid-Open No. 2008-067562 Summary of the Invention [Problem to be solved by the invention]

[0006] As described in Patent Document 3, power consumption can be reduced by slowing down the operating clock. However, this slows down the operating speed and lengthens the processing time, which reduces the throughput of the processing device.

[0007] The present invention has been made in consideration of the above circumstances, and has an object to provide a technique for reducing the power consumption of a processing device while maintaining a balance with throughput. [Means for solving the problem]

[0008] A machining apparatus according to one embodiment of the present invention is a machining apparatus comprising at least a holding mechanism that holds and rotates a workpiece, a machining mechanism that processes the workpiece held by the holding mechanism, and a moving mechanism that relatively moves the holding mechanism and the machining mechanism to a machining position where the workpiece is machined by the machining mechanism, and further comprising: servo motors that drive the holding mechanism, the machining mechanism, and the moving mechanism, respectively; a motor driver that operates the servo motors; a switch that turns on / off the power supplied to the motor driver; a machining condition setting unit that sets the machining conditions for machining the workpiece; a period calculation unit that calculates the planned drive period for operation of each of the servo motors based on the machining conditions set in the machining condition setting unit; a motor selection unit that selects a servo motor that is not operating based on the drive period calculated by the period calculation unit; and a switch control unit that turns off the power to the motor driver that operates the servo motor selected by the motor selection unit.

[0009] Another aspect of the present invention is a processing apparatus comprising at least a holding mechanism that holds and rotates a workpiece, a processing mechanism that processes the workpiece held by the holding mechanism, and a moving mechanism that relatively moves the holding mechanism and the processing mechanism to a processing position where the workpiece is processed by the processing mechanism, and further comprising: servo motors that drive the holding mechanism, the processing mechanism, and the moving mechanism; a motor driver that operates the servo motors; a processing condition setting unit that sets processing conditions for processing the workpiece; a period calculation unit that calculates a drive period for which each of the servo motors is scheduled to operate based on the processing conditions set in the processing condition setting unit; a motor selection unit that selects a servo motor that is not operating based on the drive period calculated by the period calculation unit, or a servo motor that may have a slow processing speed; and a clock frequency change unit that slows the clock frequency of the motor driver that operates the servo motor selected by the motor selection unit. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a technique for reducing the power consumption of a processing device while maintaining a balance with throughput. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view showing a grinding device according to an embodiment; [Figure 2] 1 is a Gantt chart showing a plan of processing to be performed by a grinding device according to an embodiment. [Figure 3] FIG. 10 is a diagram showing an example of a plan of a control state of a motor driver included in the grinding machine according to an embodiment. [Figure 4] 10 is a Gantt chart illustrating an adjusted plan for processing by a grinding device according to one embodiment. [Figure 5] FIG. 10 is a diagram showing another example of a plan of the control state of the motor driver included in the grinding machine according to the embodiment. [Figure 6] FIG. 10 is a diagram showing yet another example of a plan of the control state of the motor driver included in the grinding machine according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] FIG. 1 is a perspective view showing a grinding apparatus 1 according to one embodiment. The X-axis, Y-axis, and Z-axis directions shown in FIG. 1 are perpendicular to one another. The X-axis and Y-axis directions are substantially horizontal, and the Z-axis direction is an up-down direction (vertical direction). Of the two arrows indicating the X-axis direction, the +X side is the front and the -X side is the rear. Of the two arrows indicating the Y-axis direction, the +Y side is the left and the -Y side is the right. Of the two arrows indicating the Z-axis direction, the +Z side is the up and the -Z side is the down.

[0013] The grinding apparatus 1 is a processing device that performs grinding on wafers, which are workpieces. The grinding apparatus 1 is configured to perform a series of wafer loading, grinding, cleaning, and unloading processes, for example, fully automatically. The wafers are loaded into the grinding apparatus 1 while housed in a cassette C. The wafers processed by the grinding apparatus 1 are, for example, semiconductor wafers such as silicon and gallium arsenide, but may also be ceramic, glass, or sapphire optical device wafers.

[0014] Two cassettes C, each capable of accommodating a plurality of wafers, are placed on the front portion of the base 10 of the grinding apparatus 1. One cassette C accommodates wafers before grinding, and the other cassette C accommodates wafers after grinding. Behind the cassettes C, a robot hand 11 is provided for loading and unloading wafers into and from the cassettes C.

[0015] A positioning mechanism 20 on which unground wafers are placed is provided diagonally to the rear right of the robot hand 11, and a spinner cleaning device 30 for cleaning ground wafers is provided diagonally to the rear left of the robot hand 11. The robot hand 11 transports unground wafers from a cassette C to the positioning mechanism 20 and transports ground wafers from the spinner cleaning device 30 to the cassette C. The robot hand 11 is driven by a servo motor 12.

[0016] The positioning mechanism 20 is configured by arranging a plurality of positioning pins 22 around the temporary placement table 21, which are movable toward and away from the center of the temporary placement table 21. In the positioning mechanism 20, the plurality of positioning pins 22 abut against the outer periphery of the wafer placed on the temporary placement table 21, thereby positioning the center of the wafer to the center of the temporary placement table 21.

[0017] The spinner cleaning device 30 cleans the wafer by supplying a cleaning liquid from a cleaning nozzle 32 onto the upper surface of the wafer held by a spinner table 31 that rotates at high speed. The spinner table 31 is driven by a servo motor 33.

[0018] Between the positioning mechanism 20 and the spinner cleaning device 30, there are provided a first transfer mechanism 51 that transfers unground wafers from the positioning mechanism 20 to the chuck table 40, and a second transfer mechanism 52 that transfers ground wafers from the chuck table 40 to the spinner cleaning device 30. In each of the first transfer mechanism 51 and the second transfer mechanism 52, a transfer pad suction-holds the wafer from above, and a support arm that supports the transfer pad rotates about an axis in the Z-axis direction and moves up and down in the Z-axis direction to transfer the wafer. The first transfer mechanism 51 and the second transfer mechanism 52 are driven by a servo motor 53.

[0019] A rectangular opening extending in the X-axis direction is formed in the rear part of the base 10 of the grinding device 1. This opening is covered by a movable plate 13 that can move in the X-axis direction together with the chuck table 40, and a bellows-shaped waterproof cover 14.

[0020] A table moving mechanism 60 that moves the chuck table 40 in the X-axis direction is provided below the waterproof cover 14. The table moving mechanism 60 includes a pair of guide rails 61 extending in the X-axis direction, a ball screw 62, and a moving base 63, and is configured such that a servo motor 64 rotates the ball screw 62, causing the moving base 63, to which the chuck table 40 is fixed, to move in the X-axis direction along the guide rails 61. The table moving mechanism 60 is driven by the servo motor 64.

[0021] Further provided below the waterproof cover 14 is a table rotation mechanism 70 that rotates the chuck table 40 on the movable base 63. The table rotation mechanism 70 includes a driven pulley 71 provided on the rotation shaft of the chuck table 40, a drive pulley 72 provided on the rotation shaft of a servo motor 74, and an endless belt 73 stretched between the driven pulley 71 and the drive pulley 72. The table rotation mechanism 70 rotates the chuck table 40 as the servo motor 74 rotates. The table rotation mechanism 70 is driven by the servo motor 74.

[0022] The chuck table 40 includes a porous plate 41 made of a porous material with fine pores formed therein. When a suction source (not shown) performs a suction operation, a suction force is generated on the upper surface of the porous plate 41, and the chuck table 40 holds the wafer by suction. That is, the upper surface of the porous plate 41 forms a holding surface 411 that holds the wafer.

[0023] A thickness measuring device 42 is also provided on the base 10. The thickness measuring device 42 includes a first height gauge that measures the height position of the upper surface of the wafer held on the holding surface 411 of the chuck table 40, and a second height gauge that measures the height position of the upper surface of the chuck table 40. The thickness measuring device 42 measures the thickness of the wafer based on the difference between the measurement value of the first height gauge and the measurement value of the second height gauge.

[0024] A column 15 is erected further rearward of a rectangular opening formed in the rear portion of the base 10. The column 15 is provided with a grinding mechanism 80 and an elevating mechanism 90 that moves the grinding mechanism 80 up and down in the Z-axis direction.

[0025] The lifting mechanism 90 includes a pair of guide rails 91 extending in the Z-axis direction and disposed on the front side of the column 15, a ball screw 92, and a lifting table 93, and is configured so that when a servo motor 94 rotates the ball screw 92, the lifting table 93, to which the grinding mechanism 80 is fixed, moves in the Z-axis direction along the guide rails 91. In other words, the lifting mechanism 90 is driven by the servo motor 94.

[0026] The grinding mechanism 80 includes a grinding wheel 82 having a plurality of grinding stones 81 arranged in a ring shape. The grinding wheel 82 is attached to a spindle 84 via a mount 83. The spindle 84 is rotatably supported by a spindle housing 85 fixed to the front surface of the lift table 93 via a holder 86. The grinding mechanism 80 grinds the upper surface of the wafer, which is suction-held on the holding surface 411 of the chuck table 40, with the grinding stones 81 arranged on the grinding wheel 82 by rotating the spindle 84 using a servo motor 87. That is, the grinding mechanism 80 is driven by the servo motor 87.

[0027] In the grinding apparatus 1 configured as described above, first, the unground wafer is removed from the cassette C by the robot hand 11 and transferred to the positioning mechanism 20. The wafer positioned by the positioning mechanism 20 has its upper surface sucked and held by the transfer pad of the first transfer mechanism 51, and is then transferred from the positioning mechanism 20 onto the chuck table 40. When the wafer is transferred from the transfer pad of the first transfer mechanism 51 to the chuck table 40, the table moving mechanism 60 positions the chuck table 40 at a transfer position near the first transfer mechanism 51 (toward the front in the X-axis direction).

[0028] When the wafer is transferred to the chuck table 40, the table moving mechanism 60 moves the chuck table 40 to position the wafer below the grinding mechanism 80. The wafer on the chuck table 40 is then ground by the grinding mechanism 80. During grinding, the rotation of the chuck table 40, the rotation of the grinding mechanism 80, and the elevation of the grinding mechanism 80 are controlled. After grinding, the table moving mechanism 60 moves the chuck table 40 to position the ground wafer at the transfer position.

[0029] Thereafter, the ground wafer is transported by the second transport mechanism 52 to the spinner cleaning device 30, where it is cleaned. After cleaning, the ground wafer is carried out of the spinner cleaning device 30 by the robot hand 11 and stored in the cassette C.

[0030] The grinding device 1 will be described in further detail below. The grinding device 1 is equipped with a holding mechanism, a processing mechanism, and a moving mechanism, and further equipped with a plurality of servo motors (servo motor 12, servo motor 33, servo motor 53, servo motor 64, servo motor 74, servo motor 87, servo motor 94) that drive these holding mechanism, processing mechanism, and moving mechanism, respectively.

[0031] More specifically, the robot hand 11, spinner table 31, first transport mechanism 51, second transport mechanism 52, and chuck table 40 are examples of holding mechanisms that hold and rotate a wafer, which is a workpiece. Therefore, the servo motor 12 that drives the robot hand 11, the servo motor 33 that drives the spinner table 31, the servo motor 53 that drives the first transport mechanism 51 and the second transport mechanism 52, and the servo motor 64 and servo motor 74 that drive the chuck table 40 via the table moving mechanism 60 and the table rotating mechanism 70 are examples of servo motors that drive holding mechanisms.

[0032] The grinding mechanism 80 is an example of a processing mechanism that processes a wafer, which is a workpiece, held on the chuck table 40, which is a holding mechanism. Therefore, the servo motor 87 that drives the grinding mechanism 80 is an example of a servo motor that drives a processing mechanism.

[0033] Furthermore, the lifting mechanism 90 and the table moving mechanism 60 are examples of moving mechanisms that relatively move the chuck table 40, which is a holding mechanism, and the grinding mechanism 80, which is a processing mechanism, to a processing position where the wafer is processed by the grinding mechanism 80. Therefore, the servo motor 94 that drives the lifting mechanism 90 and the servo motor 64 that drives the table moving mechanism 60 are examples of servo motors that drive moving mechanisms.

[0034] The grinding apparatus 1 further includes motor drivers (motor driver 121, motor driver 122, motor driver 123, motor driver 124, motor driver 125, motor driver 126, motor driver 127) that operate the respective servo motors. The driving of each servo motor included in the grinding apparatus 1 is controlled by these motor drivers. Hereinafter, when there is no need to distinguish between the respective motor drivers, each motor driver or all of them will be referred to as motor driver 120.

[0035] The grinding apparatus 1 further includes switches (switch 111, switch 112, switch 113, switch 114, switch 115, switch 116, switch 117) that turn on / off the power supplied to each motor driver 120. The power supply to each motor driver 120 is individually controlled by a switch between the power supply 130 and each motor driver 120. In the following description, when there is no need to distinguish between the individual switches, each switch or all of them will be referred to as switch 110.

[0036] The grinding apparatus 1 further includes a control unit 100. The operation of each unit of the grinding apparatus 1 is controlled by the control unit 100. The control unit 100 is configured, for example, with a processor that executes various processes and a storage unit (memory) that stores various parameters, programs, etc., and includes a processing condition setting unit 101, a period calculation unit 102, a motor selection unit 103, a switch control unit 104, and a clock frequency change unit 105 that are realized when the processor executes the program.

[0037] The processing condition setting unit 101 sets processing conditions for processing a wafer, which is a workpiece. In the grinding apparatus 1, the processing conditions set in the processing condition setting unit 101 are a grinding recipe, which is set in advance by an operator or the like. The grinding recipe includes the thickness of the wafer before grinding, the finished thickness of the wafer (thickness after grinding) for determining whether grinding is complete (ground), the rotation speed of the chuck table 40, the rotation speed of the grinding mechanism 80, the feed speed for lowering the grinding mechanism 80, etc.

[0038] The period calculation unit 102 calculates a drive period for which the operation of each of the servo motors included in the grinding apparatus 1 is scheduled based on the machining conditions set in the machining condition setting unit 101. Specifically, the period calculation unit 102 calculates the drive periods for the servo motor 12 that drives the robot hand 11, the servo motor 33 that drives the spinner table 31, the servo motor 53 that drives the first transport mechanism 51 and the second transport mechanism 52, the servo motor 64 that drives the table moving mechanism 60, the servo motor 74 that drives the table rotating mechanism 70, the servo motor 87 that drives the grinding mechanism 80, and the servo motor 94 that drives the lifting mechanism 90.

[0039] The motor selection unit 103 selects a servo motor that is not in operation based on the drive period calculated by the period calculation unit 102. The motor selection unit 103 may also select a servo motor that may have a slow processing speed based on the drive period calculated by the period calculation unit 102.

[0040] The switch control unit 104 controls the switch 110. As an example of control, the switch control unit 104 turns off the power supply to the motor driver that operates the servo motor selected by the motor selection unit 103. In other words, the switch control unit 104 turns off the power supplied to the motor driver that operates the servo motor selected by the motor selection unit 103.

[0041] The clock frequency change unit 105 controls the motor driver 120. As an example of control, the clock frequency change unit 105 slows down the clock frequency of the motor driver 120 that operates the servo motor selected by the motor selection unit 103. In other words, the clock frequency change unit 105 sets the clock frequency of the motor driver 120 that operates the servo motor selected by the motor selection unit 103 to a frequency lower than the normal clock frequency. Note that the clock frequency change unit 105 may further perform processing to return the clock frequency of the motor driver 120 that operates at a clock frequency lower than the normal clock frequency to the normal clock frequency.

[0042] In the grinding apparatus 1 configured as described above, the drive period of each servo motor is calculated from the grinding recipe, and control is performed based on the drive period to reduce the power supplied to the motor driver 120 or the power consumed by the motor driver 120. Therefore, the grinding apparatus 1 makes it possible to reduce power consumption while maintaining a balance with the throughput, and as an example, it is possible to reduce power consumption while maintaining the throughput of the grinding apparatus 1. The throughput of the grinding apparatus 1 is, for example, the number of wafers processed per unit time.

[0043] 2 and 3, an example of control performed by the grinding apparatus 1 will be specifically described below. When a series of processes for a wafer is started, the control unit 100 sets a grinding recipe in the grinding apparatus 1 based on information input by an operator (setting process), and calculates a drive period for which the operation of each servo motor is scheduled based on the set grinding recipe (calculation process).

[0044] In the calculation step, the control unit 100 first calculates the processing time of each process constituting a series of processes for a wafer based on the grinding recipe. In this example, the control unit 100 calculates the processing time of seven processes (take-out, carry-in, move, process, move, carry-out, cleaning, and storage) performed for each wafer.

[0045] The take-out process is a process in which the robot hand 11 takes out a wafer from the cassette C and places it on the positioning mechanism 20. The carry-in process is a process in which the first transport mechanism 51 suction-holds a wafer from the positioning mechanism 20 and transports it to the chuck table 40. The two movement processes are a process in which the table moving mechanism 60 moves the chuck table 40 from the transfer position to the processing position, and a process in which the table moving mechanism 60 moves the chuck table 40 from the processing position to the transfer position. The processing process is a process in which the wafer is ground, and includes a process in which the table rotation mechanism 70 rotates the chuck table 40, a process in which the grinding mechanism 80 rotates the grinding wheel 82, and a process in which the lifting mechanism 90 raises and lowers the grinding mechanism 80. The take-out process is a process in which the second transport mechanism 52 suction-holds a wafer from the chuck table 40 and transports it to the spinner cleaning device 30. The cleaning process is a process in which the spinner cleaning device 30 cleans the wafer. The storing process is a process in which the robot hand 11 stores the wafers cleaned by the spinner cleaning device 30 in the cassette C.

[0046] Next, the control unit 100 determines the timing of each process, i.e., the execution period of each process, based on the calculated processing time for each process and the constraints on the execution of each process. Note that the constraints on the execution of each process include, for example, the order of processes on the same or preceding wafers.

[0047] FIG. 2 is a Gantt chart showing the process plan performed by the grinding apparatus 1, visualizing the execution period of each process. As shown in FIG. 2, the execution periods of the preceding and following processes are planned so that there is no time lag, unless there are circumstances that restrict this. Note that the load process following the wafer unload process is constrained by the completion of the preceding wafer unload process. For this reason, in FIG. 2, the load process for the second and third wafers is not performed immediately after the unload process for the second and third wafers, but is scheduled to be performed after the preceding first and second wafer unload processes are completed.

[0048] When the execution period of each process is specified, the control unit 100 specifies the servo motor to be used for each process, and calculates the execution period of each process as the drive period of the servo motor to be used for that process.

[0049] 3 is a diagram showing an example of a plan of the control state of the motor driver provided in the grinding apparatus 1. After the calculation step is completed, the control unit 100 plans the control state of the motor driver based on the calculated drive period (planning step). Specifically, for example, as shown in FIG. 3, the control unit 100 plans the control state of the motor driver corresponding to each servo motor to be in the ON state during the drive period of each servo motor, and plans the control state of the motor driver corresponding to each servo motor to be in the OFF state during the other periods.

[0050] In Fig. 3, the controlled objects of the servo motors are listed on the vertical axis, and an example is shown in which the control states of one or more servo motors that drive the same controlled object are collectively controlled. Specifically, the transport mechanisms in Fig. 3 are the first transport mechanism 51 and the second transport mechanism 52, and the row for the transport mechanisms shows the planned control state of the servo motor 53. Furthermore, the processing units in Fig. 3 are the table rotation mechanism 70, the grinding mechanism 80, and the lifting mechanism 90, and the row for the processing units shows the planned control states of the servo motor 74, the servo motor 87, and the servo motor 94.

[0051] Moreover, the ON state, which is one of the control states, refers to a state in which the switch 110 of the motor driver 120 is in the ON state and power is supplied from the power supply 130 to the motor driver 120. The OFF state, which is one of the control states, refers to a state in which the switch 110 of the motor driver 120 is in the OFF state and power is not supplied from the power supply 130 to the motor driver 120.

[0052] When the planning step is completed, the control unit 100 controls the grinding device 1 so that a series of processes are performed on the wafer while controlling the control state of the motor driver based on the plan created in the planning step (control step).

[0053] Specifically, when the control state of a motor driver is planned to be in the ON state, the control unit 100 controls the switch 110 corresponding to that motor driver to be in the ON state, and when the control state of the motor driver is planned to be in the OFF state, the control unit 100 controls the switch 110 corresponding to that motor driver to be in the OFF state, and controls the grinding device 1 so that a series of processes are executed.

[0054] By controlling the motor driver so as to realize the control state shown in Figure 3, it is possible to cut off the power supply to the motor driver 120 of the servo motor outside of the driving period. Therefore, it is possible to reduce the power consumed by each servo system consisting of the servo motor and the motor driver 120 during standby, and as a result, it is possible to reduce the power consumption of the grinding apparatus 1 consumed in a series of processes on wafers. Furthermore, because the power supply to the motor driver during the driving period is ensured, it is possible to avoid any impact on throughput. Therefore, according to the grinding apparatus 1 that performs the control shown in Figure 3, it is possible to reduce power consumption while maintaining throughput.

[0055] Another example of control performed by the grinding apparatus 1 will be specifically described below with reference to Figures 4 and 5. This example is similar to the example described with reference to Figures 2 and 3 in that the control unit 100 first performs a setting step and a calculation step. After the calculation step is completed, the control unit 100 adjusts the execution period of each process based on the calculated drive period, and calculates a drive period corresponding to the adjusted execution period (adjustment step).

[0056] In the adjustment process, the control unit 100 first identifies processes for which it is acceptable for the processing speed to be slowed down. Note that a process for which it is acceptable for the processing speed to be slowed down refers to a process for which the throughput does not decrease, or does not decrease significantly, even if the processing speed is slowed down. Here, an example is shown in which the throughput does not decrease even if the processing speed is slowed down.

[0057] The control unit 100, for example, identifies processes that make up a critical path of a series of processes, and identifies other processes as processes for which it is okay for the processing speed to be slower. The critical path can be identified, for example, from the schedule of driving periods shown in FIG.

[0058] In this example, the critical path is the removal, loading, movement, processing, movement, and removal of the first wafer, and the loading, movement, processing, movement, and removal of the second and subsequent wafers. In other words, the processing speed can be slowed down for the processes (cleaning, storage) after the removal of the first wafer, and the processes (removal) before the removal of the second and subsequent wafers and the processes (cleaning, storage) after the removal of the second and subsequent wafers without affecting throughput. The control unit 100 identifies these processes as processes for which the processing speed can be slowed down.

[0059] When processes that can be slowed down are identified, the control unit 100 extends the processing time of those processes. Furthermore, the control unit 100 adjusts the execution period of each process that arises as the processing time is extended. Figure 4 is a Gantt chart showing the adjusted plan of processes to be performed by the grinding device 1, and visualizes the adjusted execution period of each process.

[0060] Figure 4 shows that the processing time for the processes (cleaning, storage) after the unloading of the first wafer is extended. It also shows that the processing time for the processes (unloading) before the loading of the second and subsequent wafers and the processing time for the processes (cleaning, storage) after the unloading are extended. In particular, it shows that the start time of the unloading process for the third and subsequent wafers (N+2th wafer) is delayed due to the extension of the processing time for the storage process for the first and subsequent wafers (Nth wafer).

[0061] When the adjusted execution period of each process is identified, the control unit 100 identifies the servo motor used for each process, and calculates the adjusted execution period of each process as the drive period of the servo motor used for that process.

[0062] After the adjustment process is completed, the control unit 100 plans the control state of the motor driver based on the newly calculated drive period (planning process). Specifically, for example, as shown in FIG. 5, the control unit 100 plans the control state of the motor driver corresponding to each servo motor to be in the OFF state outside the drive period of each servo motor. This is similar to the plan shown in FIG. 3. Furthermore, during the drive period corresponding to a process on the critical path, the control unit 100 plans the control state of the motor driver 120 corresponding to that servo motor to be in the ON state and the clock frequency to be a normal frequency. Furthermore, during the drive period corresponding to a process not on the critical path (a process for which the processing speed may be slower), the control unit 100 plans the control state of the motor driver 120 corresponding to that servo motor to be in the ON state and the clock frequency to be a frequency lower than the normal frequency.

[0063] When the planning step is completed, the control unit 100 controls the grinding device 1 so that a series of processes are performed on the wafer while controlling the control state of the motor driver based on the plan created in the planning step (control step).

[0064] Specifically, when the control state of a motor driver is planned to be in the ON state, the control unit 100 controls the switch 110 corresponding to that motor driver to be in the ON state, and when the control state of a motor driver is planned to be in the OFF state, the control unit 100 controls the switch 110 corresponding to that motor driver to be in the OFF state, while controlling the grinding apparatus 1 so that a series of processes is executed. Furthermore, when controlling the switch 110 to be in the ON state, the control unit 100 switches the clock frequency of the motor driver 120 depending on whether a normal frequency or a frequency lower than the normal frequency is planned as the clock frequency of the motor driver 120.

[0065] 5, motor driver 121 of servo motor 12 that drives robot hand 11 and motor driver 122 of servo motor 33 that drives spinner table 31 may be operated at a frequency lower than normal except when the first wafer is removed. Also, motor driver 123 of servo motor 53 that drives first transport mechanism 51 and second transport mechanism 52, motor driver 124 of servo motor 64 that drives table moving mechanism 60, motor driver 125 of servo motor 74 that drives table rotating mechanism 70, motor driver 126 of servo motor 87 that drives grinding mechanism 80, and motor driver 127 of servo motor 94 that drives lifting mechanism 90 may be operated at normal frequencies.

[0066] 5, it is possible to cut off the power supply to the motor driver 120 of the servo motor outside the driving period, thereby reducing the power consumed by each servo system while it is on standby. In addition, since the power supply to the motor driver is ensured during the driving period, it is possible to avoid any impact on throughput.

[0067] Furthermore, by identifying processes that are not on the critical path from the drive period in which operation is scheduled and processing those processes at a clock frequency lower than normal, it is possible to reduce the power consumed by the motor driver 120 during the drive period. Therefore, according to the grinding apparatus 1 that performs the control shown in Fig. 5, it is possible to further reduce power consumption while maintaining throughput.

[0068] It should be noted that when the control shown in FIG. 5 is executed, the same level of throughput as when the control shown in FIG. 3 is executed can be confirmed by the fact that in both the cases of FIG. 4 and FIG. 2, the storage of the second wafer is completed at time t50.

[0069] The embodiments of the present invention are not limited to the above-described embodiments, and may be variously modified, substituted, or altered without departing from the spirit and scope of the technical idea of ​​the present invention. Furthermore, if the technical idea of ​​the present invention can be realized in a different way due to technological advances or other derived technologies, it may be implemented using that method. Therefore, the claims cover all embodiments that may fall within the scope of the technical idea of ​​the present invention.

[0070] In the above-described embodiment, for example, as shown in Fig. 3, an example was shown in which the control unit 100 cuts off the power supply to the motor driver 120 with the switch 110 outside the drive period of the servo motor, but it is not necessary to cut off the power supply as long as the amount of power consumed outside the drive period can be reduced. For this reason, as shown in Fig. 6, outside the drive period of the servo motor, the clock frequency of the motor driver 120 may be set to a clock frequency lower than normal, in other words, a clock frequency lower than during the drive period, to reduce power consumption.

[0071] Furthermore, in the above-described embodiment, a grinding device 1 was given as an example of a processing device, but the processing device may be any device equipped with a servo motor, and may be, for example, a processing device that performs other processing processes such as a cutting device or a polishing device, or may be a processing device that performs multiple processing processes.

[0072] Furthermore, in the above-described embodiment, servo motors that drive the robot hand 11, spinner table 31, first conveying mechanism 51, second conveying mechanism 52, table moving mechanism 60, table rotating mechanism 70, grinding mechanism 80, and lifting mechanism 90 are exemplified, but the control unit 100 may also perform the above-described control on any servo motor provided in the processing apparatus, such as a servo motor that drives the positioning mechanism 20, a servo motor that drives the cleaning nozzle 32, or a servo motor that drives the thickness measuring device 42. [Industrial Applicability]

[0073] As described above, the machining device of the present invention can reduce power consumption by calculating the drive period of the servo motor based on the machining conditions and controlling the state of the motor driver based on the calculated drive period, which is extremely useful for reducing power consumption in machining devices. [Explanation of symbols]

[0074] 1: Grinding equipment 11: Robot Hand 12, 33, 53, 64, 74, 87, 94: Servo motor 31: Spinner table 40: Chuck table 51: First conveying mechanism 52: Second conveying mechanism 60: Table movement mechanism 70: Table rotation mechanism 80: Grinding mechanism 90: Lifting mechanism 100: Control unit 101: Processing condition setting section 102: Period calculation section 103: Motor selection unit 104: Switch control section 105: Frequency change unit 110, 111, 112, 113, 114, 115, 116, 117: Switches 120, 121, 122, 123, 124, 125, 126, 127: Motor drivers

Claims

1. A processing device comprising at least a holding mechanism that holds and rotates a workpiece, a processing mechanism that processes the workpiece held by the holding mechanism, and a moving mechanism that relatively moves the holding mechanism and the processing mechanism to a processing position where the workpiece is processed by the processing mechanism, servo motors for driving the holding mechanism, the processing mechanism, and the moving mechanism; a motor driver that operates the servo motor; a switch for turning on / off the power supplied to the motor driver; a processing condition setting unit that sets processing conditions for processing the workpiece; a period calculation unit that calculates a drive period during which each operation of the servo motor is scheduled based on the machining conditions set in the machining condition setting unit; a motor selection unit that selects the servo motor that is not in operation based on the drive period calculated by the period calculation unit; a switch control unit that turns off the power supply of the motor driver that operates the servo motor selected by the motor selection unit, Processing equipment.

2. A processing device comprising at least a holding mechanism that holds and rotates a workpiece, a processing mechanism that processes the workpiece held by the holding mechanism, and a moving mechanism that relatively moves the holding mechanism and the processing mechanism to a processing position where the workpiece is processed by the processing mechanism, servo motors for driving the holding mechanism, the processing mechanism, and the moving mechanism; a motor driver that operates the servo motor; a processing condition setting unit that sets processing conditions for processing the workpiece; a period calculation unit that calculates a drive period during which each operation of the servo motor is scheduled based on the machining conditions set in the machining condition setting unit; a motor selection unit that selects the servo motor that is not in operation or the servo motor that may have a slow processing speed based on the drive period calculated by the period calculation unit; a clock frequency changing unit that slows down the clock frequency of the motor driver that operates the servo motor selected by the motor selecting unit, Processing equipment.

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