JP5892831B2 - Cutting equipment - Google Patents

Description

  The present invention relates to a cutting apparatus having a cutting blade.

  Workpieces such as ceramic substrates, resin substrates, and glass substrates used for semiconductor wafers, electronic components, and optical components are divided into individual chips by a cutting device, and the divided chips are widely used in various electric devices. .

  In these cutting devices, cutting of a workpiece is performed by cutting into a workpiece while a cutting blade in which superabrasive grains such as diamond and CBN (Cubic Boron Nitride) are hardened with metal, resin, glass, or the like is rotating. Done.

  The cutting blade is worn with the cutting, and the cutting blade that is worn and cannot be cut is replaced with a new cutting blade. The cutting blade is clamped by a jig called a mount or a flange and attached to the spindle. Usually, immediately after the cutting blade is mounted on the spindle, the center of the cutting blade and the shaft center of the spindle are mounted slightly deviated and are eccentric.

  Thus, when the spindle center and the rotation center of the cutting blade mounted on the spindle are slightly eccentric, the cutting blade is orthogonal to the spindle axis when the spindle with the cutting blade is rotated at high speed. Vibrates in the direction, that is, the cutting direction.

  When the wafer is cut along the wafer street in a state where the cutting blade vibrates, there is a problem that relatively large chipping (chipping) occurs on both sides of the cutting groove, thereby deteriorating the quality of the device.

  Therefore, after the cutting blade is mounted on the spindle, a rounding dressing for correcting the outer diameter of the cutting blade is performed in order to make the center of the cutting blade coincide with the axis of the spindle.

  This round dressing is performed by cutting a dressboard in which general abrasive grains such as GC (Green Carbonundum) and WA (White Alundum) are hardened with resin or glass with a cutting blade. As a result of wear, the outer shape of the cutting blade is corrected.

  In addition, the cutting blade after the rounding dressing has a finer grain size than the dressboard used in the rounding dressing in order to adjust the cutting blade condition by protruding the abrasive grains. Dressing dressing is performed to cut the dressboard mixed with grains. Also, when dressing continues after cutting, sharp dressing is necessary.

JP 2006-218571 A

  Cutting blades vary greatly in wear properties depending on the size of the abrasive grains contained, the type of bonding agent, and the thickness (blade thickness) of the cutting blade. Therefore, if an operator selects dressing conditions that are not appropriate and performs dressing, the cutting blade may be excessively worn and the cutting blade may be damaged.

  The present invention has been made in view of such points, and the object of the present invention is to reduce the risk of excessive wear and damage of a new cutting blade and to reduce the processing quality due to the deviation of a perfect circle. It is providing the cutting device which can prevent deterioration of this.

According to the present invention, there is provided a cutting apparatus for cutting a workpiece, a chuck table that holds the workpiece, a spindle that is rotationally driven, and a workpiece that is mounted on the tip of the spindle and held on the chuck table. Cutting means including a cutting blade for cutting an object, input means for inputting type information of the cutting blade, processing feed means for relatively moving the chuck table and the cutting means in the processing feed direction, and the chuck table Indexing means for relatively moving the cutting means in an indexing feed direction orthogonal to the machining feed direction, positioning means for positioning the cutting blade at a predetermined height position, the machining feed means and the index feed means, comprising control means for controlling the said positioning means, and control means, status selectable dress condition corresponding to each type of the cutting blade In accordance with a plurality memorized dress condition storage unit, to the corresponding address condition corresponding to the seed such information the cutting blade entered by said input means is selected from the dress condition storage unit, the chuck table and the cutting and means have a, a dress actuating unit carrying out the dressing of the cutting blade so cut the said cutting blade dressing board held by the chuck table while relatively moving in the processing-feed direction, the cutting blade exchange If the dressing board has been replaced, a suitable dressing board is held on the chuck table in accordance with the corresponding dress condition selected from the dress condition storage unit according to the cutting blade after replacement, and the cutting blade is in accordance with the corresponding dress condition. There is provided a cutting device characterized by performing a rounding dressing .

  In the cutting apparatus of the present invention, the control unit has a dress condition storage unit that stores a dress condition corresponding to each type of cutting blade, and the corresponding dress condition based on the type information of the cutting blade input by the input unit Is selected and the dress is performed.

  Accordingly, it is possible to prevent the operator from performing dressing by mistake under a dress condition that is not suitable for the cutting blade, and to reduce the possibility that the new cutting blade is excessively worn or damaged. In addition, it is possible to prevent deterioration of processing quality due to deviation of a perfect circle by performing an appropriate perfect circle.

It is a perspective view of the cutting device concerning the embodiment of the present invention. It is a perspective view of the semiconductor wafer supported by the annular frame via the dicing tape. It is a disassembled perspective view which shows a mode that a blade mount is fixed to the front-end | tip of a spindle. It is a disassembled perspective view which shows a mode that a washer blade is mounted | worn with a blade mount. It is a disassembled perspective view which shows a mode that a hub blade is mounted | worn with a blade mount. It is a top view of the braid | blade accommodation case which has a barcode which accommodated the washer blade. It is a perspective view of the hub blade which has a barcode. It is a disassembled perspective view which shows a mode that a dressboard is stuck on the dicing tape with which the outer peripheral part was mounted | worn with the annular frame. It is a perspective view which shows an example of a wafer cassette. It is a side view which shows a dressing operation | work. FIG. 11A is a perspective view showing a state in which a true circle deviation amount is detected by the contact setup sensor, and FIG. 11B is a schematic front view thereof.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Referring to FIG. 1, a perspective view of a cutting device 2 according to an embodiment of the present invention is shown. On the front side of the cutting apparatus 2, an operation panel 4 is provided for an operator to input instructions to the apparatus such as machining conditions. In the upper part of the apparatus, a display monitor 6 such as a CRT on which a guidance screen for an operator and an image captured by an imaging unit described later are displayed is provided.

  As shown in FIG. 2, the semiconductor wafer 11 to be cut by the cutting apparatus 2 is made of a silicon wafer having a thickness of 100 μm, for example, and a plurality of streets (division lines) are formed in a lattice pattern on the surface 11a. In addition, devices 15 such as ICs and LSIs are formed in each region partitioned by a plurality of streets 13.

  A plurality of semiconductor wafers (hereinafter sometimes simply referred to as wafers) 11 are affixed to a dicing tape T attached to an annular frame F, and then housed in a plurality of wafer cassettes 8 shown in FIG. The wafer cassette 8 is placed on a cassette elevator 9 that can move up and down.

  Behind the wafer cassette 8, a loading / unloading unit 10 is provided for unloading the wafer 11 from the wafer cassette 8 and loading the wafer after cutting into the wafer cassette 8.

  Between the wafer cassette 8 and the carry-in / out unit 10, a temporary placement area 12, which is an area on which the wafer 11 to be carried in / out, is temporarily placed, is provided. An alignment mechanism 14 is provided for aligning the position at a certain position.

  A transport unit 16 having a swivel arm that sucks and transports the wafer 11 is disposed in the vicinity of the temporary placement area 12, and the wafer 11 that has been transported to the temporary placement area 12 and aligned is transported by the transport unit 16. Is sucked and conveyed onto the chuck table 18 and sucked and held by the chuck table 18.

  The chuck table 18 is configured to be rotatable and reciprocally movable in the X-axis direction by a machining feed mechanism (not shown). An area to be cut of the wafer 11 is formed above the movement path of the chuck table 18 in the X-axis direction. An alignment unit 22 for detection is provided. Reference numeral 20 denotes a clamp for clamping the annular frame F.

  The alignment unit 22 includes an imaging unit 24 that images the surface of the wafer 11, and can detect a region to be cut by processing such as pattern matching based on an image acquired by imaging. The image acquired by the imaging unit 24 is displayed on the display monitor 6.

  On the left side of the alignment unit 22, a cutting unit 26 for cutting the wafer 11 held on the chuck table 18 is disposed. The cutting unit 26 is configured integrally with the alignment unit 22, and both move together in the Y-axis direction and the Z-axis direction.

  The cutting unit 26 is configured by mounting a washer-shaped cutting blade (washer blade) 30 on the tip of a rotatable spindle 28 and is movable in the Y-axis direction and the Z-axis direction. The cutting blade 30 is located on the extended line of the imaging unit 24 in the X-axis direction. The movement of the cutting unit 26 in the Y-axis direction is achieved by an index feed mechanism (not shown).

  Reference numeral 34 denotes a spinner cleaning unit that cleans the wafer 11 that has been subjected to the cutting process. The wafer 11 that has been subjected to the cutting process is transported to the spinner cleaning unit 34 by the transport unit 32, and is subjected to spin cleaning and spin drying by the spinner cleaning unit 34. .

  A barcode reader 36 is attached to the front side of the cutting device 2. The barcode reader 36 reads a barcode attached to a hub blade, which will be described later, or a barcode attached to a blade housing case of a washer blade. A contacted setup sensor 38 is disposed adjacent to the chuck table 18.

  Referring to FIG. 3, an exploded perspective view showing how the blade mount 44 is attached to the tip of the spindle 28 is shown. In the spindle housing 40 of the cutting unit 26, a spindle 28 that is rotationally driven by a servo motor (not shown) is rotatably accommodated. The spindle 28 has a tapered portion 28a and a small distal end portion 28b, and a male screw 42 is formed on the small distal end portion 28b.

  A blade mount 44 includes a boss portion 46 and a fixed flange 48 formed integrally with the boss portion 46, and a male screw 50 is formed on the boss portion 46. Further, the blade mount 44 has a mounting hole 51.

  In the blade mount 44, the mounting hole 51 is inserted into the small diameter portion 28b and the tapered portion 28a of the spindle 28, and the nut 52 is screwed into the male screw 50 and tightened, so that the small diameter of the tip of the spindle 28 is shown in FIG. It is attached to the part 28b.

  Referring to FIG. 4, there is shown an exploded perspective view showing how a washer-like cutting blade 30 is mounted on a blade mount 44 fixed to the tip of the spindle 22. The cutting blade 30 is composed of a cutting blade (electroforming grindstone) electroformed entirely.

  The cutting blade 30 is inserted into the boss portion 46 of the blade mount 44, the detachable flange 54 is further inserted into the boss portion 46, the fixing nut 56 is screwed onto the male screw 52, and the cutting blade 30 is fixed to the fixing flange 48. And is attached to the spindle 28 by being sandwiched from both sides by the detachable flange 54.

  Referring to FIG. 5, there is shown an exploded perspective view showing how the cutting blade 58 is mounted on the blade mount 44 fixed to the tip of the spindle 28. The cutting blade 58 is called a hub blade, and is configured by electrodepositing a cutting edge 58 a in which diamond abrasive grains are dispersed in a nickel base material on the outer periphery of a circular base 60 having a circular hub 62.

  The hub blade 58 is attached to the spindle 28 by inserting the mounting hole 63 of the hub blade 58 into the boss portion 46 of the blade mount 44 and screwing the fixing nut 64 into the male screw 50 of the boss portion 46 and tightening.

  The cutting blades 30 and 58 are worn with the cutting, and the cutting blades that are worn and cannot be cut are replaced with new cutting blades. To replace the washer blade 30, loosen the fixing screw 56, remove the old washer blade 30 together with the attachment / detachment flange 54, insert a new washer blade 30 into the boss portion 46 of the blade mount 44, and further attach the attachment / detachment flange 54 to the boss portion 46. By inserting and fixing the fixing nut 56 to the male screw 50 and tightening, the new washer blade 30 is sandwiched from both sides by the fixing flange 48 and the detachable flange 54 and attached to the spindle 28.

  To replace the hub blade 58, loosen the fixing nut 64, remove the old hub blade 58, insert the new hub blade 58 into the boss portion 46 of the blade mount 44, and screw the fixing nut 64 into the male screw 50 of the boss portion 46. Then, a new hub blade 58 is attached to the spindle 28 by tightening.

  However, immediately after the new cutting blades 30 and 58 are mounted on the spindle 28, the center of the cutting blade and the shaft center of the spindle are slightly decentered. If cutting is performed as it is, the processing quality may be deteriorated. There is.

  Therefore, after the cutting blades 30 and 58 are mounted on the spindle 28, a perfect circle for correcting the outer diameter of the cutting blades 30 and 58 in order to make the centers of the cutting blades 30 and 58 coincide with the axis of the spindle 28. Dressing is carried out.

  This round dressing is performed by cutting a dressboard made of general abrasive grains such as GC and WA with a bonding agent such as resin or glass with a cutting blade. The wear resistance varies greatly depending on the type of bonding agent and the thickness of the cutting blade (blade thickness).

  Therefore, if the operator selects dressing conditions that are not appropriate and performs dressing, the cutting blade may be excessively worn and the cutting blade may be damaged.

  Therefore, in the present invention, by cutting a plurality of types of dress boards for each type of cutting blade, the optimum dress conditions are extracted, and the optimum dress conditions are stored in a dress condition storage unit of a controller (not shown) of the cutting apparatus 2. Keep it. The optimum dress condition is input by operating the operation panel 4. A plurality of dress conditions corresponding to each type of cutting blade are stored in the dress condition storage unit of the controller.

  The type information of the cutting blade includes, for example, a washer blade, a hub blade, an abrasive particle size, a blade blade thickness, a blade blade tip amount, a type of a bond material that fixes the abrasive particles, and the like.

  As the dress board, in addition to the perfectly round dress board 74, the dress board is called a sharp dress board in which abrasive grains having a finer particle diameter are mixed as compared to the dress board used in the completely round dressing, or a pre-cut board. Includes general abrasive-containing metal, resin, vitrified dressboards, glass, silicon, GaAs wafers.

  Examples of the information included in the dress condition include a dressboard type, a cutting blade cutting amount into the dressboard, a feed speed during cutting, an index amount, a cutting distance (the number of processing pieces), and the like.

  When the washer blade 30 is replaced with a new one, a barcode 70 for identifying the internal washer blade is attached to a blade housing case 68 for housing the washer blade according to the type of the washer blade, as shown in FIG. Keep it.

  The operator reads the barcode 70 with the barcode reader 36 to display the optimum dress condition on the monitor 6 and performs dressing of the new washer blade 30 according to the dress condition.

  On the other hand, when the hub blade 58 is replaced with a new hub blade 58, as shown in FIG. 7, for example, a barcode 72 for identifying the hub blade 58 is formed in the hub 62 portion of the hub blade 58.

  The operator reads the barcode 72 with the barcode reader 36 to display the optimum dress condition on the monitor 6 and performs dressing of the new hub blade 58 according to the dress condition.

  As shown in FIG. 8, the dress board 74 is attached to a dicing tape T, which is an adhesive tape having an outer peripheral portion attached to the annular frame F, and is accommodated in the wafer cassette 8. The wafer cassette 8 has a configuration as shown in FIG. 9, for example.

  Without attaching the dressboard to the dicing tape T, a storage rack for storing the dressboard separately and a dedicated holding board for holding the dressboard directly in the dress are provided. You may make it provide the exclusive conveyance unit which conveys.

  The wafer cassette 8 shown in FIG. 9 has a right side wall 76 and a left side wall 78 facing each other, and the right side wall 76 and the left side wall 78 are connected to each other by a top plate 80 and a bottom connecting plate 82 to form a square shape. Is formed. The right side wall 76, the left side wall 78, and the top plate 80 define the accommodating portion 8a.

  The wafer cassette 8 has a front opening 8 b for taking a workpiece into and out of the wafer cassette 8. The rear surface of the wafer cassette 8 is also open. A plurality of shelves 84 extending in the front-rear direction are formed inside the right wall 76.

  Similarly, a plurality of stages of shelves 86 extending in the front-rear direction are also formed inside the left side wall 78. The shelf 84 of the right side wall 76 and the shelf 86 of the left side wall 78 are formed so as to face each other correspondingly.

  A stopper 88 extending in a direction orthogonal to the shelf 84 of the right side wall 76 and the shelf 86 of the left side wall 78 is disposed in the rear opening of the wafer cassette 8, and is accommodated in the wafer cassette 8 by the stopper 88. The processed workpiece is prevented from falling off from the back side.

  In the present embodiment, the upper shelves 84 and 86 indicated by symbol A are dressboard accommodating portions that accommodate a plurality of types of dressboards, and the lower shelves 84 and 86 indicated by symbol B accommodate workpieces. It is a workpiece storage part. The dressing board housing portion A of the wafer cassette 8 has a housing position determined according to the type of dress board, and stores each dress board in a predetermined position.

  When a worker performs dressing of a new washer blade 30 in a perfect circle, as shown in FIG. 6, the barcode 70 of the blade housing case 68 that houses the new washer blade 30 is read by the barcode reader 36. Various dress conditions are displayed on the monitor 6.

  In response to the reading of the bar code 70, the carry-in / out unit 10 takes out the optimum dressboard from the dressboard accommodating part A of the wafer cassette 8, aligns it in the temporary placement area 12, and then moves the dressboard 74 in the transport unit 16. Is brought into the chuck table 18, the dress board 74 is sucked and held by the chuck table 18 through the dicing tape T, and the annular frame F is clamped and fixed by the clamp 20.

  Then, as shown in FIG. 10, according to the dress conditions displayed on the monitor 6, the hub blade 30 is cut into the dressboard 74 while rotating at high speed in the direction of arrow A, and the chuck table 18 is moved at a predetermined speed in the direction of arrow X1. The round washer dressing of the washer blade 30 is performed by processing and feeding.

  After performing the dressing, as shown in FIG. 11, it is detected whether or not the washer blade 30 is completely circled by the contact setup sensor 38. As shown in FIG. 11A, the upper half of the hub blade 30 is covered with a blade cover 92, and cutting water supply nozzles 94 extend on both sides of the hub blade 30.

  The contact setup sensor 38 includes a block 96 having a notch 97, and a light emitting unit 98 and a light receiving unit 100 are attached so as to face the notch 97, as shown in FIG. The light emitting unit 98 is connected to the light emitting element, and the light receiving unit 100 is connected to the light receiving element.

  The washer blade 30 is inserted into the notch 97 of the contacted setup sensor 38 while rotating at a high speed in the direction of arrow A, and the light emitted from the light emitting unit 98 is detected by the light receiving unit 100, and the amount of light received by the light receiving unit 100 is detected. Accordingly, it is detected whether or not the washer blade 30 is eccentric.

  If the amount of received light is constant, it is determined that there is no eccentricity, and it is determined that the perfect circle dressing of the washer blade 30 has been properly performed. If there is a change in the amount of received light, it is determined that there is eccentricity, and true circle dressing using the dress board 74 is performed again.

  If the amount of received light is substantially constant and the round motion is less than the allowable value, the workpiece is processed. Or depending on the case, dressing dressing or pre-cutting is performed, and then the workpiece is processed.

T dicing tape F annular frame 8 wafer cassette 11 semiconductor wafer 18 chuck table 26 cutting unit 28 spindle 30 cutting blade (washer blade)
44 Blade mount 48 Fixed flange 54 Detachable flange 58 Cutting blade (hub blade)
68 Blade housing case 70, 72 Bar code 74 Dress board

Claims (1)

A cutting device for cutting a workpiece,
A chuck table for holding the workpiece;
A cutting means including a spindle that is rotationally driven, and a cutting blade that cuts a workpiece that is attached to the tip of the spindle and held on the chuck table;
Input means for inputting the type information of the cutting blade;
A machining feed means for relatively moving the chuck table and the cutting means in a machining feed direction;
Index feed means for relatively moving the chuck table and the cutting means in an index feed direction orthogonal to the machining feed direction;
Positioning means for positioning the cutting blade at a predetermined height position;
Control means for controlling the processing feed means, the index feed means, and the positioning means,
The control means includes a dress condition storage unit that stores a plurality of dress conditions corresponding to each type of cutting blade in a selectable manner ;
In response to the cutting blade that species such information entered by said input means follow the corresponding address conditions selected from the dress condition storage unit, and the chuck table and the cutting means are moved relative to the machining feed direction while organic and dress actuating portion, a which was cut to the cutting blade dressing board held by the chuck table to implement the dressing the cutting blade,
When the cutting blade is replaced, a suitable dressing board is held by the chuck table in accordance with the corresponding dress condition selected from the dress condition storage unit according to the cutting blade after replacement, and in accordance with the corresponding dress condition. A cutting apparatus for performing a perfect circle dressing of the cutting blade .

Images