Processing equipment

Abstract

To clean a wider range of a processing chamber cover than that of fluid jet from a nozzle.SOLUTION: A processing device includes: a chuck table which holds a workpiece; a processing unit which has spindles and processes the workpiece suctioned and held by the chuck table with processing tools respectively attached to lower end parts of the spindles; a processing chamber cover which has a top plate and a side wall and covers the lateral side and the upper side of the chuck table and the processing tool; and a vibration application unit which has a vibration element and applies vibration to the side wall and the top plate of the processing chamber cover.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a processing apparatus having a chuck table, a processing unit equipped with a processing tool for processing a workpiece held by suction on the chuck table, and a processing chamber cover for covering the chuck table and the processing tool. [Background technology]

[0002] Device chips are mounted on electronic devices such as mobile phones. The device chips are manufactured, for example, by grinding the back side of a wafer on which a plurality of planned division lines (streets) are set in a lattice pattern on the surface and devices such as ICs (Integrated Circuits) are formed in each area partitioned by the plurality of streets, and then dividing the wafer along each street.

[0003] For grinding the wafers, a grinding device having a rough grinding unit and a finish grinding unit is used (see, for example, Patent Document 1). Each of the rough grinding unit and the finish grinding unit has a cylindrical spindle housing.

[0004] A portion of a cylindrical spindle is rotatably accommodated in the spindle housing. The lower end of the spindle protrudes downward below the bottom of the spindle housing, and an annular grinding wheel is attached to the lower end of the spindle.

[0005] A rough grinding wheel is attached to the lower end of the spindle of the rough grinding unit, and a finish grinding wheel is attached to the lower end of the spindle of the finish grinding unit. The back side of the wafer is thinned to a predetermined thickness through rough grinding and finish grinding.

[0006] One chuck table is disposed immediately below the rough grinding unit, and another chuck table is disposed immediately below the finish grinding unit. The one chuck table and the rough grinding wheel, and the other chuck table and the finish grinding wheel are covered with a machining chamber cover (see, for example, Patent Document 2).

[0007] The machining chamber cover limits the scattering range of grinding chips generated during grinding, mist generated by atomizing grinding water supplied during grinding, etc. However, as the scattering of grinding chips, grinding water, etc. is limited by the machining chamber cover, the grinding chips adhere to and accumulate on the inner surfaces of the top plate, side plates, etc. of the machining chamber cover.

[0008] If the accumulated grinding debris falls onto the backside of the wafer during grinding, it will have a negative effect on the grinding accuracy, and if it falls onto the backside of the wafer after grinding, it will have a negative effect on the wafer during the processing steps after grinding. To prevent this, the inside of the processing chamber cover is cleaned.

[0009] For example, it is known to clean the inside of a processing chamber cover by providing multiple nozzles on the inner surface of the top plate of the processing chamber cover and spraying a gas-liquid mixed fluid of water and air from each nozzle (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0010] [Patent Document 1] JP 2000-288881 A [Patent Document 2] JP 2010-247272 A Summary of the Invention [Problem to be solved by the invention]

[0011] However, it is difficult to completely spread the gas-liquid mixed fluid over the entire inside of the top plate and side plate of the processing chamber cover. The present invention has been made in consideration of the above problems, and has an object to clean a wider area of ​​the processing chamber cover than by fluid injection from a nozzle. [Means for solving the problem]

[0012] According to one aspect of the present invention, a machining apparatus includes a chuck table for holding a workpiece, a processing unit having a spindle and processing the workpiece held by suction on the chuck table with a processing tool attached to a lower end of the spindle, a processing chamber cover having a top plate and a side wall and covering the sides and above of the chuck table and the processing tool, and a vibration imparting unit having a vibration element for imparting vibration to the side wall and the top plate of the processing chamber cover. The processing chamber cover is supported via a cushioning material on a base on which the processing unit is supported. A processing apparatus is provided.

[0013] Preferably, the vibration element comprises an ultrasonic transducer. 。 Effect of the Invention

[0014] A processing device according to one aspect of the present invention includes a vibration imparting unit having a vibration element, which applies vibration to the side walls and top plate constituting the processing chamber cover to remove grinding debris adhering to the processing chamber cover, thereby cleaning a wider area of ​​the processing chamber cover than by fluid injection from a nozzle. [Brief description of the drawings]

[0015] [Figure 1] FIG. 2 is a perspective view of the grinding apparatus with the machining chamber cover removed. [Diagram 2] FIG. 2 is a perspective view of the grinding apparatus with the machining chamber cover attached. [Diagram 3] FIG. 4 is a partial cross-sectional side view showing the inside of the processing chamber cover. [Figure 4] 11 is a partial cross-sectional side view showing the inside of a processing chamber cover in a second embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] An embodiment according to one aspect of the present invention will be described with reference to the accompanying drawings. First, a grinding device (processing device) 2 according to a first embodiment will be described with reference to Fig. 1. The grinding device 2 has a base 4 that supports each of its components.

[0017] Cassette mounting tables 6a and 6b are provided on the front side of the base 4. For example, a cassette 8a that accommodates a wafer (workpiece) 11 before grinding is mounted on the cassette mounting table 6a, and for example, a cassette 8b that accommodates a wafer 11 after grinding is mounted on the cassette mounting table 6b.

[0018] A wafer transport robot 10 for transporting a wafer 11 adjacent to the cassette mounting stages 6a and 6b is provided on the base 4. In addition, a positioning table 12 for determining the position of the wafer 11 is provided behind the cassette mounting stage 6a.

[0019] A base end of a loading arm 18 is provided behind the positioning table 12. A first suction and holding unit that sucks the wafer 11 by negative pressure is provided at the tip of the loading arm 18.

[0020] The loading arm 18 carries the wafer 11 onto the disk-shaped turntable 14 provided behind the base end of the loading arm 18. The base end of an unloading arm 20 is provided adjacent to the base end of the loading arm 18 in the lateral direction.

[0021] A second suction and holding unit that uses negative pressure to suck the wafer 11 is provided at the tip of the unloading arm 20. The unloading arm 20 carries the wafer 11 out of the turntable .

[0022] The turntable 14 is configured to be rotatable about a predetermined rotation axis. On the upper surface of the turntable 14, three chuck tables 16 are arranged at approximately equal intervals along the circumferential direction of the turntable 14.

[0023] The upper surface side of the turntable 14 is divided into three sector-shaped areas by a plurality of linear partition plates (not shown) arranged radially. The sector-shaped area closest to the base ends of the loading arm 18 and the unloading arm 20 is a loading / unloading area A where the wafer 11 is loaded onto or unloaded from the turntable 14.

[0024] The sector-shaped area approximately 120 degrees clockwise from the loading / unloading area A when viewed from above is the rough grinding area B where rough grinding of the wafers 11 is performed, and the sector-shaped area approximately 120 degrees counterclockwise from the loading / unloading area A when viewed from above is the finish grinding area C where finish grinding of the wafers 11 is performed.

[0025] Each sector-shaped region is provided with one chuck table 16. The upper surface of the chuck table 16 functions as a holding surface 16a that suction-holds the wafer 11. A rotation drive source (not shown), such as a motor, for rotating the chuck table 16 around a predetermined rotation axis is provided below the chuck table 16.

[0026] A wall portion 4a is provided behind the turntable 14. Ball screw type grinding feed mechanisms 22a and 22b are provided in front of the wall portion 4a. The grinding feed mechanism 22a moves a rough grinding unit (processing unit) 24a along the Z-axis direction. The rough grinding unit 24a is supported by the base 4 via the grinding feed mechanism 22a.

[0027] The area directly below the rough grinding unit 24a corresponds to the above-mentioned rough grinding region B. The rough grinding unit 24a has a cylindrical spindle housing 26. A part of a columnar spindle 28 is rotatably accommodated inside the spindle housing 26.

[0028] A rotation drive source 30 such as a motor is provided at the upper end of the spindle 28. The lower end of the spindle 28 protrudes downward from the bottom of the spindle housing 26, and a rough grinding wheel (machining tool) 34a is attached to the lower end of the spindle 28 via a disk-shaped mount 32.

[0029] The rough grinding wheel 34a has an annular wheel base made of metal such as an aluminum alloy. On one side of the wheel base, a plurality of segment-shaped rough grinding stones are arranged at approximately equal intervals along the circumferential direction of the wheel base.

[0030] The rough grinding unit 24a roughly grinds (processes) the back side of the wafer 11 that is suction-held by the chuck table 16 arranged in the rough grinding region B. The sides and above of the chuck table 16 and the rough grinding wheel 34a arranged in the rough grinding region B are covered by a rough grinding chamber cover 38 of a processing chamber cover 36 made of a metal such as stainless steel.

[0031] Like the grinding feed mechanism 22a, the grinding feed mechanism 22b moves the finish grinding unit (processing unit) 24b along the Z-axis direction. The finish grinding unit 24b is supported by the base 4 via the grinding feed mechanism 22b. The area directly below the finish grinding unit 24b corresponds to the above-mentioned finish grinding region C.

[0032] The finish grinding unit 24b also has a spindle housing 26, a spindle 28, a rotary drive source 30, and a mount 32. A finish grinding wheel (machining tool) 34b is attached via the mount 32 to the lower end of the spindle 28 of the finish grinding unit 24b.

[0033] On one side of the wheel base of the finish grinding wheel 34b, a plurality of segment-shaped finish grinding stones are arranged at approximately equal intervals along the circumferential direction of the wheel base. The finish grinding stones have abrasive grains with a smaller average grain size than the rough grinding stones, and a bond material that fixes the abrasive grains.

[0034] The finish grinding unit 24b finish-grinds (processes) the back side of the wafer 11 that is suction-held by the chuck table 16 arranged in the finish grinding area C. The sides and above of the chuck table 16 and the finish grinding wheel 34b arranged in the finish grinding area C are covered by a finish grinding chamber cover 40 that constitutes the processing chamber cover 36.

[0035] Next, the machining chamber cover 36 (the rough grinding chamber cover 38 and the finish grinding chamber cover 40) will be described in more detail. Fig. 1 is a perspective view of the grinding device 2 with the machining chamber cover 36 removed, and Fig. 2 is a perspective view of the grinding device 2 with the machining chamber cover 36 attached.

[0036] As shown in FIG. 1, the rough grinding chamber cover 38 has a boundary side wall 36a, a front side wall 38a, a rear side wall 38b, an outer side wall 38c, a top plate 38d, etc., and these components form a predetermined space.

[0037] A cylindrical portion 38e that surrounds the outer periphery of the spindle housing 26 is provided on the upper surface of the top plate 38d. In addition, a door portion 38f that allows an operator to access the inside of the rough grinding chamber cover 38 is provided on the top plate 38d near the cylindrical portion 38e.

[0038] Similarly, the finish grinding chamber cover 40 has a boundary side wall 36a, a front side wall 40a, a rear side wall 40b, an outer side wall 40c, a top plate 40d, etc., and these components form a predetermined space.

[0039] A cylindrical portion 40e that surrounds the outer periphery of the spindle housing 26 is provided on the upper surface of the top plate 40d. In addition, a door portion 40f that allows an operator to access the inside of the finish grinding chamber cover 40 is provided on the top plate 40d near the cylindrical portion 40e.

[0040] In this embodiment, the rough grinding chamber cover 38 and the finish grinding chamber cover 40 are integrally formed. That is, the top plates 38d and 40d are connected to each other near the boundary side wall 36a located at the boundary between the rough grinding chamber cover 38 and the finish grinding chamber cover 40.

[0041] The front sidewalls 38a, 40a join adjacent the boundary sidewall 36a, and similarly the rear sidewalls 38b and 40b join adjacent the boundary sidewall 36a.

[0042] In addition, the gap between the front side walls 38a, 40a and the upper surface of the turntable 14 is approximately closed by a partition plate (not shown) fixed to the upper surface of the turntable 14 to prevent grinding chips and the like from scattering from inside the processing chamber cover 36 into the loading / unloading area A.

[0043] In this embodiment, one vibration imparting unit 42 is attached to the outside of the outer side wall 40c. The vibration imparting unit 42 includes a rectangular plate-shaped ultrasonic transducer (vibration element) 44 that includes piezoelectric ceramics such as lead zirconate titanate (PZT) (see FIG. 3).

[0044] Fig. 3 is a partially sectional side view showing the inside of the processing chamber cover 36. As shown in Fig. 3, an AC voltage of a predetermined frequency at which the ultrasonic transducer 44 resonates is applied to the ultrasonic transducer 44 from a high-frequency power generator 46 such as an oscillator.

[0045] The ultrasonic transducer 44 is disposed so that its polarization direction is approximately perpendicular to the outer sidewall 40c. When the ultrasonic transducer 44 vibrates at a predetermined ultrasonic frequency of about 100 kHz to 1 MHz (see the double-headed arrow in FIG. 3), the vibration of the outer sidewall 40c is transmitted to the entire processing chamber cover 36.

[0046] In this manner, ultrasonic vibrations are applied to the front sidewall 38a, the rear sidewall 38b, the outer sidewall 38c and the top plate 38d, the front sidewall 40a, the rear sidewall 40b, the outer sidewall 40c and the top plate 40d, and the boundary sidewall 36a.

[0047] In this embodiment, the vibration imparting unit 42 imparts ultrasonic frequency vibrations to the side walls and top plate that constitute the processing chamber cover 36, causing grinding chips adhering to the processing chamber cover 36 to fall and removing the grinding chips from the processing chamber cover 36.

[0048] In contrast, when the inside of the processing chamber cover 36 is cleaned by jetting fluid from a nozzle, a dead angle may be formed where the fluid does not reach. However, by directly vibrating the processing chamber cover 36, a wider area of ​​the processing chamber cover 36 can be cleaned compared to the case of jetting fluid from a nozzle.

[0049] Furthermore, since the ultrasonic frequency vibrations are transmitted to the entire machining chamber cover 36, if grinding water is attached to the machining chamber cover 36, not only the grinding chips but also the grinding water can be dropped and removed.

[0050] Next, there will be described a method of using the grinding apparatus 2. First, a predetermined number of wafers 11 contained in a cassette 8a are sequentially carried into the chuck table 16 located in the carry-in / carry-out area A.

[0051] The first wafer 11 is roughly ground in the rough grinding area B and then finish ground in the finish grinding area C. During this finish grinding, the second wafer 11 is roughly ground, and the third wafer 11 is loaded onto the chuck table 16 in the load / unload area A.

[0052] When the first wafer 11 is returned to the carry-in / carry-out area A, the second wafer 11 is finish-ground in the finish grinding area C, and the third wafer 11 is rough-ground in the rough grinding area B. During the finish grinding of the second wafer 11 and the rough grinding of the third wafer 11, the first wafer 11 is carried out from the carry-in / carry-out area A, and the fourth wafer 11 is carried in instead.

[0053] After finish grinding, the wafer 11 is carried out from the loading / unloading area A to a spinner cleaning device 48, where the surface to be ground (i.e., the back surface) is mainly cleaned, and then the wafer 11 is dried (processing step).

[0054] The dried wafers 11 are transferred to the cassette 8b by the wafer transfer robot 10. In this manner, all the wafers 11 in the cassette 8a are successively ground and cleaned, and then transferred to the cassette 8b.

[0055] After the processing step, the vibration imparting unit 42 is operated to impart ultrasonic frequency vibration to the processing chamber cover 36. This causes grinding debris, grinding water, and the like adhering to the processing chamber cover 36 to fall and be removed from the processing chamber cover 36 (cleaning step). At this time, the wafer 11 shown by the dashed line in FIG. 3 is not on the holding surface 16a.

[0056] Grinding chips may fall onto the holding surface 16a. However, grinding chips that have fallen onto the holding surface 16a are washed and removed by a cleaning unit (not shown) provided near the carry-in / carry-out area A. The cleaning unit has, for example, a nozzle that sprays cleaning water such as pure water, and a leveling stone made of alumina or the like and having a predetermined hardness.

[0057] In this embodiment, a vibration imparting unit 42 having an ultrasonic vibrator 44 imparts vibrations to the processing chamber cover 36, thereby removing grinding debris adhering to the processing chamber cover 36. This makes it possible to clean a wider area of ​​the processing chamber cover 36 than when the processing chamber cover 36 is cleaned by spraying fluid from a nozzle.

[0058] During the machining process, the machining chamber cover 36 may be vibrated at ultrasonic frequencies. This makes it difficult for grinding debris and grinding water to adhere to the machining chamber cover 36. Therefore, in the cleaning process after the grinding process, grinding debris and the like can be more reliably removed from the machining chamber cover 36.

[0059] Next, a second embodiment will be described. Fig. 4 is a partial cross-sectional side view showing the inside of a processing chamber cover 36 in the second embodiment. In the second embodiment, the processing chamber cover 36 is supported on the upper surface of the base 4 via a cushioning material 50.

[0060] The cushioning material 50 is, for example, a typical vibration-isolating rubber or vibration-proof rubber used in machine tools, but may be made of an elastic material such as rubber, resin, etc. By providing the cushioning material 50, the transmission of ultrasonic frequency vibrations to the base 4 can be reduced.

[0061] Therefore, even if the vibration imparting unit 42 is operated during the processing of the wafer 11, ultrasonic frequency vibrations are less likely to be transmitted to the rough grinding unit 24a, the finish grinding unit 24b, or the chuck table 16, thereby reducing the impact of the vibrations of the vibration imparting unit 42 on the processing accuracy.

[0062] In addition, the structures, methods, and the like according to the above-described embodiments can be appropriately modified and implemented without departing from the scope of the present invention. In the above-described embodiment, the vibration imparting unit 42 is provided on the outer side of the outer side wall 40c.

[0063] However, the vibration imparting unit 42 may be provided on another side wall or on the top plate. Also, the vibration imparting unit 42 may be provided on the inside of the processing chamber cover 36 instead of on the outside.

[0064] In the above-mentioned example in which the rough grinding chamber cover 38 and the finish grinding chamber cover 40 are integrally formed, it is sufficient to attach one vibration imparting unit 42 to the processing chamber cover 36, but multiple vibration imparting units 42 may be attached to the processing chamber cover 36.

[0065] However, when a plurality of vibration imparting units 42 are attached to the processing chamber cover 36, the arrangement, vibration frequency, amplitude, etc. of each vibration imparting unit 42 are appropriately adjusted so that the vibrations do not interfere with each other and cancel each other out.

[0066] Incidentally, when the rough grinding chamber cover 38 and the finish grinding chamber cover 40 are not connected to each other but are separated, one or more vibration imparting units 42 are provided on each of the rough grinding chamber cover 38 and the finish grinding chamber cover 40 . [Explanation of symbols]

[0067] 2: grinding device (processing device), 4: base, 4a: wall 6a, 6b: cassette placement table, 8a, 8b: cassette, 10: wafer transport robot 11: wafer (workpiece), 12: positioning table, 14: turntable 16: chuck table, 16a: holding surface 18: loading arm, 20: unloading arm 22a, 22b: Grinding feed mechanism 24a: Rough grinding unit (processing unit) 24b: Finish grinding unit (processing unit) 26: spindle housing, 28: spindle, 30: rotation drive source, 32: mount 34a: Rough grinding wheel (machining tool), 34b: Finish grinding wheel (machining tool) 36: Processing chamber cover, 36a: Boundary side wall 38: Rough grinding chamber cover, 40: Finish grinding chamber cover 38a, 40a: Front side wall, 38b, 40b: Back side wall, 38c, 40c: Outer side wall 38d, 40d: Top plate, 38e, 40e: Cylinder section, 38f, 40f: Door section 42: vibration imparting unit, 44: ultrasonic vibrator (vibration element), 46: high-frequency power generator 48: Spinner cleaning device, 50: Cushioning material A: Loading / unloading area, B: Rough grinding area, C: Finish grinding area

Claims

1. A chuck table for holding the workpiece; a processing unit having a spindle and processing the workpiece held by the chuck table with a processing tool attached to a lower end of the spindle; a machining chamber cover having a top plate and a side wall and covering the sides and the top of the chuck table and the machining tool; a vibration imparting unit having a vibration element and imparting vibration to the side wall and the top plate of the processing chamber cover, The processing apparatus is characterized in that the processing chamber cover is supported via a cushioning material on a base on which the processing unit is supported.

2. 2. The processing apparatus according to claim 1, wherein the vibration element comprises an ultrasonic vibrator.

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