Processing equipment

Abstract

To reduce the weight of a mechanism which moves up or down a dressing grindstone so as to cause the dressing grindstone to contact with a processing surface of a polishing pad.SOLUTION: A processing device 1 includes: a mechanism 4 which causes a processing surface of a processing tool 45 to contact with a workpiece held by a table 3 to process the workpiece; and a mechanism 5 which dresses the processing surface with a ring-shaped dressing grindstone 50. The dress mechanism 5 includes: a grindstone 50 which is disposed so as to enclose the table 3; and a mechanism 51 which moves up or down the grindstone 50 relative to the processing surface. The lifting mechanism 51 includes: an airbag 511 disposed in a ring shape below the grindstone 50; an air valve 513 which supplies air to the airbag 511; and a suction valve 515 which allows the airbag 511 to communicate with a suction source 59 to suction air in the airbag 511. A control part 53 provides control in which air is supplied from the air valve 513 to the airbag 511 to cause the grindstone 50 to contact with the processing surface at the time of dressing of the processing surface and air is suctioned from the airbag 511 by the suction valve 515 to separate the grindstone 50 from the processing surface when the processing surface is not dressed.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] For example, as disclosed in Patent Literature 1, a polishing apparatus provided with an elevating mechanism for elevating a ring-shaped dresser board (dress grinding wheel) presses the dress grinding wheel against a polishing pad by using the elevating mechanism during polishing, and rotates it together with a chuck table that holds a workpiece to perform dressing. Therefore, the elevating mechanism is disposed on a rotating mechanism that rotates the chuck table.

Prior Art Documents

Patent Literature

[0003]

Patent Literature 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, since the above-described elevating mechanism is heavy, a large amount of power needs to be supplied to the motor of the rotating mechanism when starting the rotation of the chuck table. Also, when stopping the rotation of the chuck table, a large amount of power needs to be supplied to the brake that functions by electricity. Therefore, there is a problem in that it is desired to reduce the weight of the elevating mechanism that raises and lowers the ring-shaped dress grinding wheel to bring it into contact with the processing surface (lower surface) of a processing tool such as a polishing pad.

Means for Solving the Problems

[0005] The present invention, for solving the above problems, is a machining apparatus comprising: a chuck table that holds and rotates a workpiece on a holding surface; a machining mechanism that processes a workpiece by bringing the machining surface of a machining tool into contact with the workpiece held on the holding surface; and a dressing mechanism that dresses the machining surface with a ring-shaped dressing grinding wheel, wherein the dressing mechanism is ring-shaped and arranged on the outer circumference of the chuck table and has a plurality of radial grooves on its upper surface The chips pass through the groove and are discharged outside the chuck table while the machined surface is dressed. The processing apparatus comprises a dressing grinding wheel, a lifting mechanism for moving the dressing grinding wheel perpendicular to the processing surface, and a control unit, wherein the lifting mechanism includes an airbag arranged in a ring shape below the dressing grinding wheel, an air supply unit for supplying air into the airbag, and an air intake unit for connecting the airbag to a suction source and sucking in the air from the airbag, and the control unit controls the upper surface of the dressing grinding wheel, which rotates with the rotating chuck table, to contact the processing surface when dressing the processing surface of the processing tool while processing a workpiece by supplying air to the airbag with the air supply unit, and when not dressing the processing surface of the processing tool while processing a workpiece by sucking in air from the airbag with the air intake unit to move the upper surface of the dressing grinding wheel to a position lower than the upper surface of the workpiece, thereby separating the upper surface of the dressing grinding wheel from the processing surface. In the processing apparatus according to the present invention, for example, the control unit may alternately operate the air supply unit and the air intake unit to dress the processing surface of the processing tool while processing the workpiece by repeatedly bringing the dressing grinding wheel into contact with and separating from the processing surface. The processing apparatus according to the present invention comprises a pressure gauge for measuring the air pressure inside the airbag and an electro-pneumatic regulator capable of adjusting the air pressure inside the airbag to a predetermined pressure. Preferably, the control unit controls the electro-pneumatic regulator so that the pressure value of the pressure gauge becomes a preset pressure value, thereby adjusting the force with which the dressing wheel is pressed against the processing surface and dressing the processing surface. Furthermore, the present invention, which solves the above problems, processes the upper surface of a workpiece with a processing tool using the above processing apparatus. and manufacture the workpieceA method for manufacturing a workpiece, comprising: a holding step of holding the workpiece on the chuck table; a processing step of bringing the processing surface of the processing tool into contact with the upper surface of the workpiece, rotating the chuck table and the processing tool relative to each other, and processing the workpiece; and a dressing step in which, in the processing step, the upper surface of a dressing grinding wheel that rotates due to the rotation of the chuck table comes into contact with the processing surface, and dresses the processing surface. In the dressing process, when dressing the workpiece surface of the workpiece tool, the air supply unit supplies air to the airbag to bring the upper surface of the dressing grinding wheel, which rotates with the chuck table, into contact with the workpiece surface. When not dressing the workpiece surface of the workpiece tool, the air intake unit draws air from the airbag to move the upper surface of the dressing grinding wheel to a position lower than the upper surface of the workpiece, thereby separating the upper surface of the dressing grinding wheel from the workpiece surface. This process of contact and separation of the dressing grinding wheel with the workpiece surface is repeated. [Effects of the Invention]

[0006] The processing apparatus according to the present invention allows the dressing wheel to be raised and lowered by an airbag arranged in a ring shape beneath it, thus enabling a lighter mechanism for raising and lowering the dressing wheel compared to conventional methods. Furthermore, because the lifting mechanism incorporates an airbag, controlling the raising and lowering motion of the dressing wheel is less complex than in conventional methods. In the processing apparatus according to the present invention, radial grooves are formed on the upper surface of the dressing wheel, centered on the center of the dressing wheel. This allows tool scraps generated by dressing, as well as processing scraps generated during the processing of the workpiece performed simultaneously with dressing, to be discharged from the grooves to the outside of the chuck table. [Brief explanation of the drawing]

[0007] [Figure 1] This is a side view showing an example of a polishing device (processing device). [Figure 2] This is a perspective view showing an example of a chuck table and dressing mechanism. [Figure 3] This is a perspective view showing a cross-section of the chuck table and dressing mechanism. [Figure 4] This is a partial cross-sectional view illustrating the process of polishing a workpiece with a polishing pad, while simultaneously raising a dressing wheel using an airbag to bring it into contact with the workpiece surface of the polishing pad and dress the workpiece surface. [Figure 5] This is a partial cross-sectional view illustrating a state in which the upper surface of the dressing wheel is separated from the machining surface of the polishing pad by an airbag, and positioned at a height lower than the back surface of the workpiece. [Modes for carrying out the invention]

[0008] Figure 1 shows a polishing apparatus 1, which is an example of a processing apparatus according to the present invention. The processing apparatus according to the present invention may also be a grinding apparatus that thins the workpiece 90 by grinding it with a rotating grinding wheel. The polishing apparatus 1 comprises at least a chuck table 3 that holds the workpiece 90 on a holding surface 30, a processing mechanism 4 (hereinafter referred to as the polishing mechanism 4) that processes the workpiece 90 by bringing the processing surface 451 of a polishing pad 45, which is a processing tool, into contact with the workpiece 90 held on the holding surface 30, and a dressing mechanism 5 that dresses the processing surface 451 with a dressing wheel 50 which has a ring shape in plan view.

[0009] The workpiece 90 shown in Figure 1 is, for example, a circular semiconductor wafer made of a silicon matrix. In Figure 1, the surface 902 of the workpiece 90, which faces downwards, has multiple devices formed on it and is protected by protective tape (not shown). The back surface 901 of the workpiece 90, which faces upwards, is the work surface to be polished. The workpiece 90 may be made of materials other than silicon, such as gallium arsenide, sapphire, gallium nitride, resin, ceramics, or silicon carbide, or it may be a package substrate.

[0010] The chuck table 3 shown in Figures 1 and 2 has, for example, a circular outer shape, and a suction source 39, such as a vacuum generator, is connected to its upper surface, which is a holding surface 30 made of a porous material or the like. The suction force generated by the suction source 39 is transmitted to the holding surface 30, allowing the chuck table 3 to hold the workpiece 90 on the holding surface 30 by suction. The plate-shaped porous material that makes up this holding surface 30 is housed in a frame 31.

[0011] The frame 31 shown in Figures 1, 2, and 3 is made of a dense material such as ceramics, and comprises a frame base 311 whose outer shape is circular in plan view, and an annular wall 312 erected at a predetermined height in the outer peripheral region of the upper surface of the frame base 311. The annular region in plan view of the upper surface of the frame base 311, shown in Figure 1, outside the annular wall 312, is a flat arrangement surface 313 on which the lifting mechanism 51 and the dressing grinding wheel 50 are arranged. The region of the frame 31 inside the annular wall 312 is a circular recess that accommodates the plate-shaped porous member that constitutes the holding surface 30.

[0012] The chuck table 3 is capable of reciprocating in the Y-axis direction by a horizontal movement mechanism (not shown) consisting of a ball screw or motor, and is also capable of rotating around a rotation axis with the Z-axis direction (vertical direction) as its axis. The chuck table 3 may be mounted on a turntable and be capable of revolving in a horizontal plane by the turntable.

[0013] The polishing mechanism 4 shown in Figure 1 comprises a spindle 40 whose axis is the Z-axis direction, a motor 42 that rotates the spindle 40, a circular plate-shaped mount 43 connected to the lower end of the spindle 40, and a polishing pad 45 attached to the lower surface of the mount 43 via a circular plate-shaped platen 44. The polishing mechanism 4 is also capable of moving up and down in the Z-axis direction (vertical direction) by a vertical movement mechanism (not shown) consisting of a ball screw and a motor.

[0014] The disc-shaped polishing pad 45 is made of, for example, a nonwoven fabric such as felt, and is approximately the same size as the diameter of the mount 43, and is larger in diameter than, for example, the workpiece 90 held by the chuck table 3. The flat lower surface of the polishing pad 45 becomes the machining surface 451 that contacts the workpiece 90.

[0015] The polishing apparatus 1 in this embodiment dry-polishes the workpiece 90, but it may also be configured to perform CMP (Chemical Mechanical Polishing) using a polishing liquid. In this case, a polishing liquid flow path (not shown) extending in the Z-axis direction penetrates from the center of the spindle 40 shown in FIG. 1 to the center of the platen 44, and a polishing liquid supply source capable of delivering a polishing liquid (slurry) communicates with this polishing liquid flow path. The polishing liquid delivered from the polishing liquid supply source to the spindle 40 is supplied to the polishing pad 45 from the opening at the lower end of the polishing liquid flow path on the lower surface of the platen 44. For example, lattice-shaped grooves (not shown) are formed on the processing surface 451 of the polishing pad 45 that abuts against the back surface 901 of the workpiece 90, and the polishing liquid supplied to the polishing pad 45 mainly flows in the lattice-shaped grooves and spreads over the entire surface of the processing surface 451.

[0016] The dressing mechanism 5 shown in FIGS. 1 to 3 includes a ring-shaped dressing grindstone 50 arranged so as to surround the chuck table 3, a lifting mechanism 51 that moves the dressing grindstone 50 in the vertical direction (Z-axis direction) with respect to the processing surface 451, and a control unit 53.

[0017] The dressing grindstone 50 is, for example, a grindstone in which diamond abrasive grains are hardened in an annular plate shape with a resin bond, and its upper and lower surfaces are substantially flat surfaces. Note that the abrasive grains contained in the dressing grindstone 50 can be appropriately selected according to the type of the material of the polishing pad 45, etc., and in addition to diamond abrasive grains, for example, CBN (cubic boron nitride) abrasive grains, GC abrasive grains (green carbon), or alumina abrasive grains may also be used. Also, the bonding agent is not limited to the resin bond, and may be a ceramic bond or the like. As shown in FIGS. 2 to 3, in this embodiment, a plurality of grooves 505 are formed radially on the upper surface of the dressing grindstone 50 around the center of the dressing grindstone 50 so as to cross the ring width of the dressing grindstone 50.

[0018] The lifting mechanism 51 includes an airbag 511 arranged in a ring shape under the dress grinding wheel 50, an air valve 513 for supplying air to the cavity 510 inside the airbag 511, and an intake valve 515 for connecting the airbag 511 to a suction source 59 to intake the air inside the airbag 511.

[0019] The airbag 511 formed of an elastomer or the like, which is a soft polymer material having elasticity like rubber, is formed in a single-ring shape in a plan view in this embodiment, and its entire circumference bulges or shrinks mainly in the Z-axis direction simultaneously with substantially the same expansion rate. The inner diameter of the airbag 511 is set slightly larger than the outer diameter of the annular wall 312 of the frame body 31 in a circular ring shape in a plan view. For example, the airbag 511 and the dress grinding wheel 50 are set to have substantially the same diameter, and the dress grinding wheel 50 is adhered to the upper surface of the airbag 511 by an adhesive or the like. A slight gap 507 is formed between the inner surface of the airbag 511 and the inner surface of the dress grinding wheel 50 and the outer surface of the annular wall 312 of the frame body 31, and the gap 507 allows the expansion / contraction of the airbag 511 and the vertical movement of the dress grinding wheel 50.

[0020] The airbag 511 surrounds the annular wall 312 in a state where its lower surface is adhered to the arrangement surface 313 of the frame body 31 by an adhesive or the like. As shown in FIG. 1, an internal flow path 315 is formed inside the frame body 31, and one end of the internal flow path 315 communicates with a supply / exhaust port (not shown) of the airbag 511. The other end of the internal flow path 315 communicates with an external pipe 516.

[0021] The external pipe 516 branches into two, for example, by a three-way pipe or the like (not shown). One of the branched air suction pipes 517 communicates with an intake valve 515, which is an air intake part, for example, a solenoid valve or the like, and a suction source 59 such as a vacuum generator. Note that the suction source 39 communicating with the holding surface 30 and the suction source 59 may be the same.

[0022] The other air supply pipe 518, which branches off from the external piping 516, is connected to an air supply unit, such as an air valve 513 (e.g., a solenoid valve), and an air source 58 (e.g., a compressor). Furthermore, the air supply pipe 518 is equipped with a pressure gauge 581 for measuring the air pressure inside the airbag 511, and an electro-pneumatic regulator 582 that can adjust the air pressure inside the airbag 511 to a predetermined pressure and exhaust the air into the atmosphere.

[0023] The control unit 53 consists of a CPU that performs calculations according to a control program and a storage medium such as memory. The control unit 53 is connected to the air valve 513, intake valve 515, and electro-pneumatic regulator 582, for example, via a wired or wireless communication path.

[0024] For example, when the solenoid valve, the air valve 513, is energized from the control unit 53, it opens, connecting the air supply pipe 518 to the air source 58, and supplies air from the air source 58 to the airbag 511. When the power supply from the control unit 53 is cut off, it closes, disconnecting the air supply pipe 518 from the air source 58. For example, when the intake valve 515, which is a solenoid valve, is energized from the control unit 53, it opens up, connecting the air intake pipe 517 to the suction source 59, and transmits the suction force generated by the suction source 59 to the airbag. When the power supply from the control unit 53 is cut off, it closes, disconnecting the air intake pipe 517 from the suction source 59. For example, an electro-pneumatic regulator 582 equipped with an exhaust port (not shown) capable of exhausting air into the atmosphere can continuously adjust the pressure of the air supplied from the air source 58 to the airbag 511 in proportion to the power supplied from the control unit 53. The electro-pneumatic regulator 582 may also be installed in the air suction pipe 517. Alternatively, a manual regulator equipped with an exhaust port may be used instead of the electro-pneumatic regulator 582.

[0025] The operation of each component of the polishing apparatus 1 shown in Figure 1 when polishing a workpiece 90 held on the chuck table 3 will be described below. First, the workpiece 90 is placed on the holding surface 30 of the chuck table 3 with their centers roughly aligned, and the suction force generated by the suction source 39 is transmitted to the holding surface 30, causing the workpiece 90 to be held in place by the holding surface 30.

[0026] The chuck table 3 is moved horizontally to below the polishing mechanism 4 by a horizontal movement mechanism (not shown), and the workpiece 90 is positioned on the polishing pad 45. In this embodiment, during the polishing process, the chuck table 3 is always positioned so that the polishing surface 451 of the polishing pad 45 is in contact with the entire back surface 901 of the workpiece 90, that is, so that the polishing pad 45 covers the entire back surface 901 of the workpiece 90. In the example shown in Figure 1, for example, the polishing pad 45 is positioned so that a part of the outer edge and a part of the outer edge of the dressing wheel 50 overlap.

[0027] Next, as the spindle 40 is rotated by the motor 42, the polishing pad 45 rotates at a predetermined rotational speed. The polishing mechanism 4 also descends in the -Z direction by a vertical movement mechanism (not shown), and the polishing surface 451 of the polishing pad 45 comes into contact with the back surface 901 of the workpiece 90, thereby performing polishing. Furthermore, during polishing, as the chuck table 3 rotates, the workpiece 90 held on the holding surface 30 also rotates, and the polishing pad 45 polishes the entire back surface 901 of the workpiece 90.

[0028] In parallel with polishing the workpiece 90 with the polishing pad 45, the control unit 53 controls each component to dress the workpiece surface 451 of the polishing pad 45. Specifically, as shown in Figure 4, for example, the control unit 53 energizes the air valve 513, which is a solenoid valve, and opens the air supply pipe 518 to connect it to the air source 58. The air source 58 then supplies a predetermined amount of compressed air to the cavity 510 inside the airbag 511 through the air supply pipe 518, the external piping 516, and the internal flow path 315 of the frame 31.

[0029] As shown in Figure 4, the entire circumference of the ring-shaped airbag 511 supplied with compressed air inflates, causing the upper surface of the ring-shaped dressing wheel 50, which is positioned on the airbag 511 and lower than the back surface 901 of the workpiece 90, to rise, and the upper surface of the dressing wheel 50 comes into contact with the machining surface 451 of the polishing pad 45. As the workpiece 90 is polished, the entire machining surface 451 of the rotating polishing pad 45 is dressed by the ring-shaped dressing wheel 50 which rotates together with the chuck table 3, thus maintaining the machining surface 451 of the polishing pad 45 in an optimal state for polishing the workpiece 90 at all times.

[0030] For example, in this embodiment, the air pressure inside the airbag 511 is measured by a pressure gauge 581, and the control unit 53 receives information about the measured value. The control unit 53's storage medium stores a predetermined pressure value inside the airbag 511 that has been obtained theoretically or experimentally to ensure that the dressing wheel 50 contacts the work surface 451 of the polishing pad 45 with an appropriate pressing force. The control unit 53 then compares the received pressure reading from the pressure gauge 581 with the stored predetermined pressure value and adjusts the voltage supplied to the electro-pneumatic regulator 582 to adjust the air pressure inside the airbag 511 to the predetermined pressure value. That is, for example, when the work surface 451 of the polishing pad 45 is pressed against the dressing wheel 50, if the air pressure inside the airbag 511 is lower than the predetermined pressure, the voltage supplied to the electro-pneumatic regulator 582 is increased. Conversely, if the air pressure inside the airbag 511 is higher than the predetermined pressure value, the voltage supplied to the electro-pneumatic regulator 582 is decreased, and air is exhausted from the exhaust port. In this way, when the predetermined pressure value is also high, the electro-pneumatic regulator is adjusted to open the exhaust port more widely, increasing the amount of exhausted air, lowering the inflation rate of the airbag 511, and reducing the pressing force of the dressing wheel 50 against the workpiece surface 451. By adjusting the force with which the dressing wheel 50 presses the workpiece surface 451 of the polishing pad 45 while dressing the workpiece surface 451 in this way, the condition of the workpiece surface 451 of the polishing pad 45 can be kept at all times in an optimal state for polishing the workpiece 90.

[0031] As described above, as shown in Figures 1 and 4, polishing the workpiece 90 with the polishing pad 45 generates polishing debris 909 from the workpiece 90, and dressing the machined surface 451 of the polishing pad 45 with the dressing wheel 50 generates pad debris 459 from the polishing pad 45. In this embodiment, since a plurality of radial grooves 505 centered on the center of the dressing wheel 50 are formed on the upper surface of the dressing wheel 50 shown in Figure 2, the polishing debris 909 and pad debris 459 shown in Figure 2 that fall onto the back surface 901 of the workpiece 90 are moved radially outward from the workpiece 90 by the centrifugal force caused by the rotation of the chuck table 3, and are further discharged outside the chuck table 3 by passing through the grooves 505. Therefore, the occurrence of polishing defects in the workpiece 90 caused by the generated polishing debris 909 and pad debris 459 can be suppressed.

[0032] After the back surface 901 of the workpiece 90 shown in Figures 1 and 4 has been polished for a predetermined time, the polishing mechanism 4 is raised in the +Z direction by a vertical movement mechanism (not shown) to separate the polishing pad 45 from the workpiece 90. The workpiece 90 may also be moved back and forth horizontally relative to the polishing mechanism 4 during the polishing process. This is because, during polishing, a striped pattern may be formed on the back surface 901 of the workpiece 90, which can reduce the bending strength of the workpiece 90. Therefore, for example, during polishing, the polishing pad 45 may be made to slide horizontally relative to the back surface 901 of the workpiece 90 to prevent a decrease in the bending strength of the workpiece 90.

[0033] To stop the dressing of the polishing pad 45's workpiece surface 451, for example, the power supply from the control unit 53 to the air valve 513, which is a solenoid valve as shown in Figure 5, is stopped, causing the air valve 513 to close, disconnecting the airbag 511 from the air source 58, and stopping the supply of air to the airbag 511. Alternatively, for example, the control unit 53 powers the intake valve 515, which is a solenoid valve, opening the air intake pipe 517 to connect it to the suction source 59. The suction force generated by the suction source 59 is then transmitted to the airbag 511 through the air intake pipe 517, the external piping 516, and the internal flow path 315 of the frame 31. In other words, the intake valve 515 and the suction source 59 draw in the air that was filling the cavity 510 inside the airbag 511, causing the airbag 511 to contract, and the upper surface of the dressing wheel 50 is pulled down so that it is separated from the machining surface 451 of the polishing pad 45 and is at a height lower than, for example, the back surface 901 of the workpiece 90 after polishing.

[0034] Next, the polished workpiece 90 is removed from the chuck table 3, which is now stopped rotating. The transmission of suction force from the suction source 39 shown in Figure 1 to the chuck table 3 is stopped, and the suction holding of the workpiece 90 by the holding surface 30 is released. Then, the back surface 901 of the workpiece 90 is held by a suction pad (not shown) or the like, and the workpiece is removed from the chuck table 3. In this embodiment, as described above, the airbag 511 is retracted, and the upper surface of the dressing wheel 50 shown in Figure 5 is positioned at a lower height than the back surface 901 of the polished workpiece 90, so that the suction pad (not shown) or the like does not come into contact with the dressing wheel 50 and cause damage.

[0035] As described above, the polishing apparatus 1 according to the present invention allows the dressing wheel 50 to be raised and lowered by an airbag 511 arranged in a ring shape beneath the dressing wheel 50, thus enabling a lighter mechanism 51 for raising and lowering the dressing wheel 50 compared to conventional devices. Furthermore, because the lifting mechanism 51 is equipped with an airbag 511, controlling the raising and lowering operation of the dressing wheel 50 is not more complex than in conventional devices. It goes without saying that the polishing apparatus 1 (processing apparatus 1) according to the present invention is not limited to the above-described embodiment and may be implemented in various different forms within the scope of its technical concept. Furthermore, the shapes of each component of the polishing apparatus 1 shown in the attached drawings, as well as the polishing process for the workpiece 90, are not limited to these and can be appropriately modified within the scope that allows the effects of the present invention to be realized.

[0036] For example, the airbag 511 is not limited to being formed in the shape of a single ring as in this embodiment. For example, it may be formed in the shape of an arc in plan view, and a single ring-shaped airbag 511 may be formed by arranging a plurality of arc-shaped airbags 511 on the arrangement surface 313 of the frame 31. Furthermore, each airbag 511 may be able to inflate and deflate individually. In addition, the control unit 53 may, while performing the polishing process on the workpiece 90, alternately operate the air valve 513 and the intake valve 515 as described above, repeating the inflation and deflation of the airbag 511 at predetermined time intervals, thereby repeatedly bringing the dressing grinding wheel 50 into contact with and separating from the workpiece surface 451 of the polishing pad 45 to dress the workpiece surface 451. [Explanation of symbols]

[0037] 1: Polishing equipment (processing equipment) 3: Chuck table 30: Holding surface 31: Frame 311: Frame base 312: Annular wall 313: Placement surface 315: Internal flow path 39: Suction source 4: Polishing mechanism (processing mechanism) 40: Spindle 42: Motor 43: Mount 44: Platen 45: Polishing pad 451: Machined surface 5: Dressing mechanism 50: Dressing grinding wheel 505: Groove 51: Lifting mechanism 511: Airbag 513: Air valve (air supply unit) 515: Intake valve (air intake unit) 516: External piping 517: Air suction pipe 518: Air supply pipe 53: Control unit 58: Air source 581: Pressure gauge 582: Electro-pneumatic regulator 59: Suction source 90: Workpiece 901: Back surface of workpiece 902: Front surface of workpiece

Claims

1. A machining apparatus comprising: a chuck table that holds and rotates a workpiece on a holding surface; a machining mechanism that brings the machining surface of a tool into contact with the workpiece held on the holding surface to machine the workpiece; and a dressing mechanism that dresses the machining surface with a ring-shaped dressing grinding wheel, The dressing mechanism comprises a dressing wheel, which is ring-shaped and has multiple radial grooves on its upper surface, positioned on the outer circumference of the chuck table, and dresses the workpiece surface while discharging debris outside the chuck table as it passes through the grooves; a lifting mechanism for moving the dressing wheel perpendicular to the workpiece surface; and a control unit. The lifting mechanism comprises an airbag arranged in a ring shape beneath the dressing grinding wheel, an air supply unit that supplies air into the airbag, and an air intake unit that connects the airbag to a suction source and draws in the air from within the airbag. The control unit controls the upper surface of the dressing grinding wheel, which rotates with the chuck table, to contact the workpiece surface when dressing the workpiece surface of the workpiece tool while it is being processed, by supplying air to the air bag via the air supply unit; and controls the upper surface of the dressing grinding wheel, which rotates with the chuck table, to contact the workpiece surface when not dressing the workpiece surface of the workpiece tool while it is being processed, by drawing air from the air bag via the air intake unit, thereby moving the upper surface of the dressing grinding wheel to a position lower than the upper surface of the workpiece, and separating the upper surface of the dressing grinding wheel from the workpiece surface.

2. The system comprises a pressure gauge for measuring the air pressure inside the airbag, and an electro-pneumatic regulator capable of adjusting the air pressure inside the airbag to a predetermined pressure. The processing apparatus according to claim 1, wherein the control unit controls the electro-pneumatic regulator so that the pressure value of the pressure gauge becomes a preset pressure value, and dresses the processing surface while adjusting the force with which the dressing grinding wheel is pressed against the processing surface.

3. A method for manufacturing a workpiece, comprising processing the upper surface of the workpiece with a processing tool using the processing apparatus described in claim 1, A holding step of holding the workpiece on the chuck table, A machining process in which the machining surface of the tool is brought into contact with the upper surface of the workpiece, and the chuck table and the tool are rotated relative to each other to machine the workpiece, The machining process includes a dressing step in which the upper surface of the dressing grinding wheel, which rotates due to the rotation of the chuck table, is brought into contact with the machined surface, thereby dressing the machined surface. A method for manufacturing a workpiece.

4. The method for manufacturing a workpiece according to Claim 3, wherein the dressing step involves, when dressing the workpiece surface of the workpiece tool, supplying air to the airbag by the air supply unit to bring the upper surface of the dressing grinding wheel, which rotates together with the rotating chuck table, into contact with the workpiece surface; and when not dressing the workpiece surface of the workpiece tool, drawing air from the airbag by the air intake unit to move the upper surface of the dressing grinding wheel to a position lower than the upper surface of the workpiece, thereby separating the upper surface of the dressing grinding wheel from the workpiece surface, and repeating the contact and separation of the dressing grinding wheel with the workpiece surface.

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