Method and apparatus for processing workpiece

Abstract

To provide a new work-piece processing method in which a time required for completing a cutting process can be shortened.SOLUTION: A work-piece processing method includes: a first processing step in which a work-piece is cut on a first processing scheduled line, by making a first cutting blade being rotated cut into the work-piece, without making a second cutting blade cut into the work-piece, while moving a chuck table, a first cutting unit and a second cutting unit relatively in a first direction along a processing and feeding shaft; and a second processing step in which, after the first processing step, the work-piece is cut on a second processing scheduled line, by making the second cutting blade being rotated cut into the work-piece, without making the first cutting blade cut into the work-piece, while moving the chuck table, the first cutting unit and the second cutting unit relatively in a second direction which is opposite to the first direction.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a method and apparatus for machining a workpiece that is used when cutting the workpiece. [Background technology]

[0002] In semiconductor packaging technologies such as CSP (Chip Size Package) and QFN (Quad Flat Non-leaded Package), a package substrate is manufactured by encapsulating multiple device chips, each equipped with a device such as an electronic circuit, with resin. Each device chip is placed in one of multiple areas of the package substrate, which are partitioned by linear processing lines, and the package substrate is cut along these processing lines to obtain a package device in which the device chips are encapsulated with resin.

[0003] However, the sealing resin used in the package substrate is prone to shrinkage due to heat, etc., and if the package substrate is deformed due to this resin shrinkage, the actual position and orientation of the processing lines will deviate from the position and orientation assumed when the package substrate was designed. For example, if multiple processing lines designed to be parallel to each other are not actually parallel to each other, cutting the package substrate under the assumption that these are parallel to each other will increase the possibility of damaging the device chip.

[0004] To prevent such problems, a method has been proposed in which information about the positions and orientations of all planned processing lines is obtained using a camera or the like, and a cutting blade is inserted into each planned processing line on the package substrate based on this information (see, for example, Patent Document 1). Also proposed is a method in which the positions and orientations of the remaining planned processing lines are estimated from the positions and orientations of two planned processing lines located on both ends of the package substrate, and the cutting blade is inserted based on these positions and orientations (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 9-52227 [Patent Document 2] Japanese Patent Application Laid-Open No. 2002-33295 Summary of the Invention [Problem to be solved by the invention]

[0006] However, with the method of Patent Document 1, each time the cutting blade is cut into the target planned processing line, the package substrate must be rotated based on the acquired information to adjust the orientation of the target planned processing line. As a result, it is not possible to simultaneously cut multiple planned processing lines using multiple cutting blades, and the package substrate is cut with one cutting blade, which poses the problem of taking a long time to complete the cutting process.

[0007] In contrast, the method of Patent Document 2 estimates the position and orientation of other planned processing lines from the positions and orientations of two planned processing lines, so the time required to complete cutting is shorter than a method in which information on the positions and orientations of all planned processing lines is obtained using a camera, etc. However, the estimated positions and orientations may deviate from the actual positions and orientations of the planned processing lines, and high cutting accuracy cannot necessarily be achieved.

[0008] Therefore, an object of the present invention is to provide a new method for processing a workpiece that can shorten the time required to complete cutting, and a new processing device used in this method for processing a workpiece. [Means for solving the problem]

[0009] According to one aspect of the present invention, there is provided a method for machining a workpiece, the method comprising: a chuck table having a holding surface for holding a workpiece and rotatable about a rotation axis intersecting the holding surface; a first cutting unit having a first spindle to which an annular first cutting blade is attached and rotatable about an axis; a second cutting unit having a second spindle to which an annular second cutting blade is attached at a position opposite to the first cutting blade and rotatable about an axis; and a machining feed mechanism for relatively moving the chuck table, the first cutting unit, and the second cutting unit along a machining feed axis; a holding step; a first processing step of cutting the workpiece along the first planned processing line by relatively moving the chuck table, the first cutting unit, and the second cutting unit in a first direction along the processing feed axis, and causing the rotated first cutting blade to cut into the workpiece without causing the second cutting blade to cut into the workpiece; and a second processing step after the first processing step of cutting the workpiece along the second planned processing line by relatively moving the chuck table, the first cutting unit, and the second cutting unit in a second direction opposite to the first direction, and causing the rotated second cutting blade to cut into the workpiece without causing the first cutting blade to cut into the workpiece. an angle information acquisition step, after the holding step, of acquiring first information on the angle of the first planned processing line with respect to the processing feed axis and second information on the angle of the second planned processing line with respect to the processing feed axis; a first orientation control step, after the angle information acquisition step and before the first processing step, of controlling the orientation of the chuck table about the rotation axis based on the first information so that the first planned processing line becomes parallel to the processing feed axis; and a second orientation control step, after the first processing step and before the second processing step, of controlling the orientation of the chuck table about the rotation axis based on the second information so that the second planned processing line becomes parallel to the processing feed axis. and rotating the first cutting blade and the second cutting blade so that the relationship of the rotational direction of the first cutting blade to the first direction at a first processing point where the first cutting blade cuts into the workpiece is equal to the relationship of the rotational direction of the second cutting blade to the second direction at a second processing point where the second cutting blade cuts into the workpiece.

[0010] Preferably, The processing device further includes a first nozzle having a first outlet for discharging liquid toward the first cutting blade, and a second nozzle having a second outlet for discharging liquid toward the second cutting blade, and in the first processing step, the first cutting blade is rotated and cuts into the workpiece while liquid is being discharged from the first outlet toward the first cutting blade, and in the second processing step, the second cutting blade is rotated and cuts into the workpiece while liquid is being discharged from the second outlet toward the second cutting blade, and liquid is discharged from the first outlet and the second outlet while an orientation of the first outlet based on the first direction and an orientation of the second outlet based on the second direction are equal. .

[0011] According to another aspect of the present invention, there is provided a cutting machine including a chuck table having a holding surface for holding a workpiece and rotatable about a rotation axis intersecting the holding surface, a first cutting unit having a first spindle on which an annular first cutting blade is attached and rotatable about an axis, a second cutting unit having a second spindle on which an annular second cutting blade is attached at a position opposite to the first cutting blade and rotatable about an axis, a processing feed mechanism for relatively moving the chuck table, the first cutting unit, and the second cutting unit along a processing feed axis, and a cutting mechanism for moving the first cutting blade relative to the first cutting blade. A method for processing a workpiece, using a processing device including a first nozzle having a first outlet for discharging a liquid and a second nozzle having a second outlet for discharging a liquid toward the second cutting blade, to cut the workpiece along a first planned processing line and a second planned processing line set on the workpiece, the method comprising: a holding step of holding the workpiece on the chuck table; and a step of rotating the second cutting blade without cutting into the workpiece while moving the chuck table, the first cutting unit, and the second cutting unit relatively in a first direction along the processing feed axis. a first processing step of cutting the workpiece along the first planned processing line by cutting a first cutting blade into the workpiece; and a second processing step of, after the first processing step, cutting the workpiece along the second planned processing line by cutting the rotated second cutting blade into the workpiece without cutting the first cutting blade into the workpiece while relatively moving the chuck table, the first cutting unit, and the second cutting unit in a second direction opposite to the first direction. The first cutting blade and the second cutting blade are rotated so that a relationship of a rotation direction of the first cutting blade with respect to the first direction at a first processing point where the first cutting blade cuts into the workpiece is equal to a relationship of a rotation direction of the second cutting blade with respect to the second direction at a second processing point where the second cutting blade cuts into the workpiece, and in the first processing step, the rotated first cutting blade is caused to cut into the workpiece while liquid is being discharged from the first discharge port onto the first cutting blade, and in the second processing step,The method for processing a workpiece includes cutting the rotated second cutting blade into the workpiece, and discharging liquid from the first discharge port and the second discharge port in a state where the direction in which the first discharge port discharges liquid based on the first direction is the same as the direction in which the second discharge port discharges liquid based on the second direction.

[0012] The present invention FurthermoreAccording to another aspect, the present invention provides a cutting machine including: a chuck table having a holding surface for holding a workpiece and rotatable around a rotation axis intersecting the holding surface; a first cutting unit having a first spindle to which an annular first cutting blade is attached and rotatable around an axis; a second cutting unit having a second spindle to which an annular second cutting blade is attached at a position opposite the first cutting blade and rotatable around an axis; a processing feed mechanism that moves the chuck table, the first cutting unit, and the second cutting unit relatively along a processing feed axis; and a control unit having a processing unit and a memory unit, and that controls the first cutting unit, the second cutting unit, and the processing feed mechanism according to a program stored in the memory unit. a first nozzle having a first outlet for discharging a liquid toward the first cutting blade; and a second nozzle having a second outlet for discharging a liquid toward the second cutting blade. Including, the first nozzle and the second nozzle are arranged such that a direction of the first discharge port based on a first direction along the processing feed axis is equal to a direction of the second discharge port based on a second direction opposite to the first direction; A processing device is provided in which the control unit rotates the first spindle, on which the first cutting blade is attached, and the second spindle, on which the second cutting blade is attached, in opposite directions when viewed from the same side according to the program. [Effects of the Invention]

[0014] In one aspect of the present invention, a method for processing a workpiece involves moving the chuck table, the first cutting unit, and the second cutting unit relatively in a first direction along the processing feed axis while causing the first cutting blade to cut into the workpiece, thereby cutting the workpiece along a first planned processing line (outbound path), and then moving the chuck table, the first cutting unit, and the second cutting unit relatively in a second direction opposite to the first direction while causing the second cutting blade to cut into the workpiece, thereby cutting the workpiece along a second planned processing line (return path).Therefore, unlike conventional processing methods that only repeat cutting by relative movement in the first direction (outbound path), the time spent on relative movement in the second direction (return path) is effectively utilized, and the time required to complete cutting is shortened.

[0015] In addition, in a method for processing a workpiece according to one aspect of the present invention, the relationship between the rotational direction of the first cutting blade relative to the first direction and the relationship between the rotational direction of the second cutting blade relative to the second direction are equal, and the cutting conditions of the first planned processing line and the cutting conditions of the second planned processing line are equal, so variation in the quality of the cutting is kept small and high cutting precision is achieved.

[0016] Furthermore, in the method for processing a workpiece according to one aspect of the present invention, the time required to complete the cutting process is shortened by continuously cutting the workpiece on the outward and return paths of relative movement, so that, for example, even when information on the positions and orientations of all planned processing lines is acquired using a camera or the like to achieve higher cutting precision, the time required to complete the cutting process is shorter than in conventional methods in which the workpiece is cut only on the outward path. Therefore, it is possible to achieve high cutting precision while shortening the time required to complete the cutting process.

[0017] In addition, when liquid is supplied to the first cutting blade and the second cutting blade by ejecting liquid from the first outlet and the second outlet while the orientation of the first outlet relative to the first direction and the orientation of the second outlet relative to the second direction are the same, variation in the quality of the cutting process is further reduced, and even higher cutting precision is achieved. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a perspective view showing a cutting device. [Figure 2] FIG. 2 is a plan view showing the package substrate. [Figure 3] FIG. 3 is a bottom view showing the package substrate. [Figure 4] FIG. 4 is a plan view showing the package substrate supported by an annular frame via a dicing tape. [Figure 5] FIG. 5 is a plan view showing the angle formed by the first line to be processed with respect to the X axis. [Figure 6] FIG. 6 is a plan view showing the angle formed by the second line to be processed with respect to the X axis. [Figure 7] FIG. 7 is a plan view showing how the package substrate is cut on the first processing line. [Figure 8] FIG. 8 is a side view showing how the package substrate is cut on the first processing line. [Figure 9] FIG. 9 is a plan view showing how the package substrate is cut on the second processing line. [Figure 10] FIG. 10 is a side view showing how the package substrate is cut on the second processing line. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a perspective view showing a cutting device (processing device) 2 according to this embodiment. Note that in Fig. 1, some components are expressed as functional blocks. Furthermore, the X-axis (processing feed axis), Y-axis (indexing feed axis), and Z-axis (vertical axis) used in the following description are perpendicular to one another.

[0020] As shown in Fig. 1, the cutting device 2 includes a base 4 that supports various components. An opening 4a is formed in a corner of the top surface of the base 4, and a cassette table 6 that is raised and lowered by a lifting mechanism (not shown) is disposed within this opening 4a. A cassette 8 that can accommodate plate-shaped workpieces is placed on the top surface of the cassette table 6. For ease of explanation, only the outline of the cassette 8 is shown in Fig. 1.

[0021] Fig. 2 is a plan view showing a package substrate 11 as an example of a plate-shaped workpiece, and Fig. 3 is a bottom view showing the package substrate 11. As shown in Figs. 2 and 3, the package substrate 11 includes a substrate 13 having a rectangular front surface 13a and a rectangular back surface 13b opposite to the front surface 13a.

[0022] The substrate 13 is made of a metal such as 42 alloy (an alloy of iron and nickel) or copper, and the surface 13a side is divided into a plurality of device regions 15 (three in this embodiment) and a surplus region 17 surrounding each device region 15. Each device region 15 is further divided into a plurality of small regions by a plurality of processing lines (streets) 19, and a stage 21 is disposed in each small region.

[0023] Device chips 23 including devices such as ICs (Integrated Circuits), LEDs (Light Emitting Diodes), and MEMS (Micro Electro Mechanical Systems) are arranged on the back surface of each stage 21 (the back surface 13b side of the substrate 13). Areas corresponding to each device area 15 on the back surface 13b side of the substrate 13 are covered with a sealing resin layer (mold resin layer) 25 made of hardened sealing resin, and the device chips 23 arranged on the back surface of each stage 21 are sealed with this sealing resin layer 25.

[0024] A plurality of structures 27 made of a conductive material such as metal and insulated from one another are arranged around each stage 21 so as to overlap the processing lines 19. The structures 27 are exposed on the front surface 13a of the substrate 13 and are connected to the electrodes of the device chips 23 via metal wires (not shown) or the like. For example, one structure 27 is connected to the electrodes of the device chips 23 arranged on two adjacent stages 21 with the structure 27 sandwiched between them.

[0025] When this package substrate 11 is cut along the processing lines 19 to form package devices in which device chips 23 are sealed, the structures 27 are also divided along the processing lines 19. After division, the structures 27 become electrodes (terminals) of each package device. Marks 29 are formed in the excess region 17 (surface 13a) of the substrate 13 to indicate the positions of the processing lines 19.

[0026] In this embodiment, the workpiece is a package substrate 11 in which a portion of the back surface 13b of a substrate 13 having a rectangular front surface 13a and a back surface 13b is covered with a sealing resin layer 25, but there are no limitations on the material, shape, structure, size, etc. of the workpiece. Similarly, there are no limitations on the type, number, material, shape, structure, size, arrangement, etc. of the device chips and structures.

[0027] 4 is a plan view showing the package substrate 11 supported by an annular frame 33 via a dicing tape 31. When the package substrate 11 is cut by the cutting device 2, for example, a circular dicing tape 31 larger than the package substrate 11 is attached to the sealing resin layer 25 side of the package substrate 11, as shown in FIG.

[0028] In addition, an annular frame 33 is fixed to the outer periphery of the dicing tape 31 so as to surround the package substrate 11. In this manner, the package substrate 11 is housed in the cassette 8 while being supported by the annular frame 33 via the dicing tape 31, for example, and is then cut by the cutting device 2.

[0029] 1, an opening 4b that is long in the direction along the X-axis is formed at a position adjacent to cassette table 6 along the Y-axis. A ball screw type chuck table moving mechanism (processing feed mechanism) 10 is disposed within opening 4b. Chuck table moving mechanism 10 includes a rotational drive source (not shown) such as a motor connected to the ball screw, and an X-axis moving table (not shown), and moves the X-axis moving table along the X-axis.

[0030] The top of the X-axis moving table is covered by a table cover 10a. In addition, accordion-shaped dustproof and drip-proof covers 10b that expand and contract in accordance with the movement of the X-axis moving table (table cover 10a) are attached to both ends of the table cover 10a in the direction along the X-axis. A chuck table 12 that holds a package substrate 11, which is the workpiece, is arranged above the X-axis moving table in a manner that it is exposed from the table cover 10a.

[0031] The chuck table 12 is connected to a rotary drive source (not shown) such as a motor, and rotates around a rotation axis that is roughly parallel to the Z axis. The chuck table 12 is also moved along the X axis together with the X axis moving table by the chuck table moving mechanism 10 (processing feed).

[0032] The chuck table 12 includes a disk-shaped frame 14 made of a metal such as stainless steel. A recess 14a (see FIG. 8, etc.) with a circular opening at the top end is formed on the upper surface of the frame 14. A disk-shaped holding plate 16 that matches the shape of the recess 14a is fitted into the recess 14a. Four clamps 18 are arranged around the periphery of the frame 14 to secure an annular frame 33 that supports the package substrate 11.

[0033] The holding plate 16 is formed into a porous plate shape using a material such as ceramics, and holds the package substrate 11 on its upper surface (holding surface) 16a. The upper surface 16a of the holding plate 16 is formed so as to be approximately parallel to the X-axis and Y-axis when the holding plate 16 is fitted into the recess 14a. In other words, the chuck table 12 rotates around a rotation axis that intersects the upper surface 16a of the holding plate 16 at a substantially right angle.

[0034] A suction source (not shown) is connected to the bottom of the recess 14a of the frame 14 via a flow path 14b (see FIG. 8, etc.) provided inside the frame 14 and a valve (not shown) located outside the frame 14. Therefore, when the valve is opened, negative pressure from the suction source acts on the upper surface 16a of the holding plate 16 through the flow path 14b, etc. As the suction source, for example, a vacuum pump or the like that combines an air supply source and an ejector is used. However, a rotary pump or the like may also be used as the suction source.

[0035] Above the opening 4b, one or more transport mechanisms (not shown) are arranged that can transport the above-mentioned package substrate 11 (frame 33) to the chuck table 12, etc. The package substrate 11 transported by the transport mechanism is placed on the upper surface 16a of the chuck table 12 so that the surface 13a of the substrate 13 is exposed upward, for example.

[0036] A gate-shaped support structure 20 is provided on the upper surface of the base 4, spanning the opening 4b along the Y axis. A pair of cutting unit movement mechanisms (indexing feed mechanism, cutting feed mechanism) 22 are arranged above the support structure 20. The structures of the cutting unit movement mechanisms 22 are substantially the same except that they are configured to be symmetrical with respect to planes parallel to both the X axis and the Z axis.

[0037] Each cutting unit movement mechanism 22 shares a pair of Y-axis guide rails 24 that are fixed to the front (surface) of the support structure 20 and are generally parallel to the Y-axis. A Y-axis movement plate 26 that constitutes each cutting unit movement mechanism 22 is slidably attached to the Y-axis guide rails 24. A nut portion (not shown) that constitutes a ball screw is provided on the rear side (back side) of each Y-axis movement plate 26, and a screw shaft 28 that is generally parallel to the Y-axis guide rails 24 is rotatably connected to each nut portion.

[0038] A rotary drive source 30 such as a motor is connected to one end of each screw shaft 28. By rotating each screw shaft 28 with each rotary drive source 30, the corresponding Y-axis moving plate 26 moves along the Y-axis guide rails 24. A pair of Z-axis guide rails 32 that are generally parallel to the Z-axis are fixed to the front (surface) of each Y-axis moving plate 26. A Z-axis moving plate 34 is attached to the Z-axis guide rails 32 fixed to each Y-axis moving plate 26 in a manner that allows it to slide.

[0039] A nut portion (not shown) constituting a ball screw is provided on the rear side (back surface side) of each Z-axis moving plate 34, and a screw shaft 36 that is generally parallel to the Z-axis guide rail 32 is rotatably connected to each nut portion. A rotation drive source 38 such as a motor is connected to one end of each screw shaft 36. By rotating the screw shaft 36 with each rotation drive source 38, the corresponding Z-axis moving plate 34 moves along the Z-axis guide rail 32.

[0040] A cylindrical first spindle housing 42a constituting the first cutting unit 40a is fixed to the lower part of the Z-axis moving plate 34 constituting one cutting unit moving mechanism 22. The first spindle housing 42a accommodates a first spindle 44a (see FIG. 7, etc.) that serves as a rotation axis generally parallel to the Y-axis.

[0041] The tip of the first spindle 44a, located in an inner region of the cutting device 2, is exposed to the outside from the inner end of the first spindle housing 42a. A disk-shaped (annular) first cutting blade 46a (see FIG. 7, etc.) made of a binder with abrasive grains dispersed therein is attached to the tip of the first spindle 44a. A rotational drive source (not shown), such as a motor, that can rotate the first spindle 44a around its axis is connected to the base end of the first spindle 44a, located in an outer region of the cutting device 2.

[0042] A first cover 48a (see FIG. 8, etc.) that can partially cover the first cutting blade 46a attached to the first spindle 44a is provided at the inner end of the first spindle housing 42a. A pair of first lower nozzles 50a (see FIG. 8, etc.) that can supply a cutting liquid (cutting fluid) such as pure water to the first cutting blade 46a are arranged below the first cover 48a so as to sandwich the first cutting blade 46a.

[0043] Furthermore, a first upper nozzle (first nozzle) 52a (see FIG. 8, etc.) that can supply cutting liquid to the first cutting blade 46a is disposed on one side of the first cover 48a in two different directions along the X axis. A first discharge port 54a that opens so that the liquid can be discharged toward the other side of the two different directions along the X axis (first direction X1 in FIG. 8) is provided at the tip of the first upper nozzle 52a. Therefore, the first upper nozzle 52a can discharge liquid to the first cutting blade 46a located on the other side of the two different directions along the X axis (first direction X1).

[0044] A camera 56 capable of capturing images of the package substrate 11 and the like held on the chuck table 12 is provided adjacent to the first cutting unit 40a. When one Y-axis moving plate 26 is moved along the Y-axis by one cutting unit moving mechanism 22, the first cutting unit 40a and the camera 56 move along the Y-axis (indexing feed). When one Z-axis moving plate 34 is moved along the Z-axis by one cutting unit moving mechanism 22, the first cutting unit 40a and the camera 56 move along the Z-axis (cutting feed).

[0045] A cylindrical second spindle housing 42b constituting the second cutting unit 40b is fixed to the lower part of the Z-axis moving plate 34 constituting the other cutting unit moving mechanism 22. The second spindle housing 42b accommodates a second spindle 44b (see FIG. 7, etc.) that serves as a rotation axis generally parallel to the Y-axis.

[0046] The tip of the second spindle 44b, located in an inner region of the cutting device 2, is exposed to the outside from the inner end of the second spindle housing 42b. A disk-shaped (annular) second cutting blade 46b (see FIG. 7, etc.) made of a binder with abrasive grains dispersed therein is attached to the tip of the second spindle 44b. A rotation drive source (not shown), such as a motor, that can rotate the second spindle 44b around its axis is connected to the base end of the second spindle 44b, located in an outer region of the cutting device 2.

[0047] A second cover 48b (see FIG. 10, etc.) that can partially cover the second cutting blade 46b attached to the second spindle 44b is provided at the inner end of the second spindle housing 42b. A pair of second lower nozzles 50b (see FIG. 10, etc.) that can supply cutting liquid, such as pure water, to the second cutting blade 46b are arranged below the second cover 48b so as to sandwich the second cutting blade 46b.

[0048] Additionally, a second upper nozzle (second nozzle) 52b (see FIG. 10, etc.) capable of supplying cutting liquid to the second cutting blade 46b is disposed on the other side of the second cover 48b in two different directions along the X axis. A second outlet 54b is provided at the tip of the second upper nozzle 52b, and is open so that the liquid can be discharged in one of the two different directions along the X axis (the second direction X2 in FIG. 10). Therefore, the second upper nozzle 52b can discharge liquid to the second cutting blade 46b located in one of the two different directions along the X axis (the second direction X2).

[0049] A camera 56 capable of capturing images of the package substrate 11 and the like held on the chuck table 12 is also provided at a position adjacent to the second cutting unit 40b. When the other Y-axis moving plate 26 is moved along the Y-axis by the other cutting unit moving mechanism 22, the second cutting unit 40b and the camera 56 move along the Y-axis (indexing feed). When the other Z-axis moving plate 34 is moved along the Z-axis by the other cutting unit moving mechanism 22, the second cutting unit 40b and the camera 56 move along the Z-axis (cutting feed).

[0050] Thus, the cutting device 2 of this embodiment includes a first cutting unit 40a having a first spindle 44a to which a first cutting blade 46a is attached and which is rotatable around an axis, as well as a second cutting unit 40b having a second spindle 44b to which a second cutting blade 46b is attached in a position opposite the first cutting blade 46a and which is rotatable around an axis.

[0051] However, unlike a typical dual dicer equipped with two cutting units, in the first cutting unit 40a and the second cutting unit 40b according to this embodiment, some of the components are not arranged symmetrically with respect to a plane parallel to both the X-axis and the Z-axis. For example, as described above, the first upper nozzle 52a and the second upper nozzle 52b are not arranged symmetrically with respect to a plane parallel to both the X-axis and the Z-axis, and the first outlet 54a of the first upper nozzle 52a faces in the opposite direction to the second outlet 54b of the second upper nozzle 52b.

[0052] 1, an opening 4c is formed at a position opposite to opening 4a with respect to opening 4b. A cleaning unit 58 is disposed within opening 4c for cleaning package substrate 11 and the like after cutting. A control unit 60 is connected to components such as chuck table moving mechanism 10, a rotation drive source connected to chuck table 12, the transport mechanism, cutting unit moving mechanism 22, first cutting unit 40a, second cutting unit 40b, camera 56, and cleaning unit 58. The operation of each component is controlled by this control unit 60.

[0053] The control unit 60 is configured by a computer including, for example, a processing unit 60a which is a processing device such as a CPU (Central Processing Unit), and a storage unit 60b which is a main storage device such as a DRAM (Dynamic Random Access Memory) or an auxiliary storage device such as a hard disk drive or flash memory. The processing unit 60a operates in accordance with a program (software) stored in the storage unit 60b, thereby realizing the functions of the control unit 60. However, the control unit 60 may also be realized by hardware alone.

[0054] In this embodiment, a program for rotating the first spindle 44a, on which the first cutting blade 46a is mounted, and the second spindle 44b, on which the second cutting blade 46b is mounted, in opposite directions as viewed from one of two different directions along the Y axis (i.e., the same side) is stored (recorded) in the storage unit 60b. This reduces variations in the quality of the cutting process, as will be described later.

[0055] Next, a description will be given of a method for processing a workpiece in which the package substrate 11, which is the workpiece, is continuously cut along any two of the planned processing lines 19. However, the method for processing a workpiece according to the present invention can also be similarly applied when three or more planned processing lines 19 are continuously cut.

[0056] In the method for processing a workpiece according to this embodiment, first, the control unit 60 holds the package substrate 11 on the chuck table 12 (holding step). The control unit 60, for example, operates the transport mechanism to carry out the package substrate 11 from the cassette 8, and places the package substrate 11 on the upper surface 16a of the chuck table 12 so that the surface 13a of the substrate 13 is exposed upward.

[0057] Then, the control unit 60 opens the valve to apply negative pressure from the suction source to the upper surface 16a of the holding plate 16 on which the package substrate 11 is placed. The control unit 60 also fixes the annular frame 33 that supports the package substrate 11 with the clamp 18. As a result, the package substrate 11 is held by the chuck table 12.

[0058] After the package substrate 11 is held by the chuck table 12, the control unit 60 acquires information (first information, second information) regarding the angle that each of the planned processing lines 19 forms with respect to the X-axis (processing feed axis) (angle information acquisition step). Fig. 5 is a plan view showing the angle θ1 (θ1>0) that the first planned processing line 19a forms with respect to the X-axis, and Fig. 6 is a plan view showing the angle θ2 (θ2<0) that the second planned processing line 19b forms with respect to the X-axis. Note that, for ease of explanation, the angles θ1 and θ2 are exaggerated in Figs. 5 and 6.

[0059] The control unit 60, for example, operates the chuck table moving mechanism 10 and the cutting unit moving mechanism 22 to capture images of two areas of the package substrate 11 including two marks 29 corresponding to both ends of the first line to be processed 19a with the camera 56. Then, the control unit 60 extracts the X-axis coordinates and Y-axis coordinates (first information) of each mark 29 from the two obtained images. From the X-axis coordinates and Y-axis coordinates of each mark 29, the control unit 60 can recognize the angle θ1 that the first line to be processed 19a forms with respect to the X-axis.

[0060] Similarly, the control unit 60, for example, operates the chuck table moving mechanism 10 and the cutting unit moving mechanism 22 to capture images of two areas including two marks 29 corresponding to both ends of the second line to be processed 19b with the camera 56. Then, the control unit 60 extracts the X-axis coordinates and Y-axis coordinates (second information) of each mark 29 from the two obtained images. From the X-axis coordinates and Y-axis coordinates of each mark 29, the control unit 60 can recognize the angle θ2 that the second line to be processed 19b makes with respect to the X-axis.

[0061] In this embodiment, the X-axis coordinates and Y-axis coordinates of the two marks 29 corresponding to both ends of the first planned processing line 19a are used as the first information regarding the angle θ1 that the first planned processing line 19a makes with respect to the X-axis, but the first information may be any information that allows the control unit 60 to recognize the angle θ1 that the first planned processing line 19a makes with respect to the X-axis.

[0062] Similarly, in this embodiment, the X-axis coordinates and Y-axis coordinates of the two marks 29 corresponding to both ends of the second planned processing line 19b are used as the second information regarding the angle θ2 that the second planned processing line 19b makes with respect to the X-axis, but the second information may be any information that allows the control unit 60 to recognize the angle θ2 that the second planned processing line 19b makes with respect to the X-axis.

[0063] After the first information and the second information are acquired, the control unit 60 controls the orientation of the chuck table 12 around the rotation axis based on the first information so that the first planned processing line 19a becomes parallel to the X-axis (first orientation control step). That is, the control unit 60 operates the rotation drive source connected to the chuck table 12 to rotate the chuck table 12 clockwise by an angle θ1 when viewed from above.

[0064] After the first planned processing lines 19a are made parallel to the X-axis, the control unit 60 cuts the package substrate 11 along the first planned processing lines 19a by rotating the first cutting blade 46a (first processing step). Fig. 7 is a plan view showing how the package substrate 11 is cut along the first planned processing lines 19a, and Fig. 8 is a side view showing how the package substrate 11 is cut along the first planned processing lines 19a. Note that Fig. 8 shows the first cutting unit 40a as viewed from one of two different directions along the Y-axis.

[0065] Specifically, the control unit 60, for example, operates the chuck table moving mechanism 10 and the cutting unit moving mechanism 22 to move the first cutting blade 46a to immediately above the extension line of the first planned processing line 19a on the first direction X1 side, as shown in Fig. 7. In addition, the control unit 60, for example, operates the cutting unit moving mechanism 22 to move the lower end of the first cutting blade 46a to a position slightly lower than the lower end of the package substrate 11. Here, the control unit 60 maintains the lower end of the second cutting blade 46b at a position higher than the upper end of the package substrate 11 so that the second cutting blade 46b does not cut into the package substrate 11.

[0066] 8, for example, the control unit 60 operates the chuck table moving mechanism 10 while rotating the first cutting blade 46a in the rotation direction R1, to move the chuck table 12 together with the package substrate 11 in the first direction X1. At this time, the control unit 60 causes the first lower nozzle 50a and the first upper nozzle 52a to eject liquid onto the first cutting blade 46a.

[0067] As a result, the rotated first cutting blade 46a cuts into the package substrate 11, and the package substrate 11 is cut along the first planned processing line 19a. In this embodiment, the position of the lower end of the first cutting blade 46a is lower than the position of the lower end of the package substrate 11, so the package substrate 11 is cut along the first planned processing line 19a. After the package substrate 11 is cut along the first planned processing line 19a, the control unit 60 stops the movement of the chuck table 12 in the first direction X1.

[0068] In this way, the control unit 60 moves the chuck table 12 and the first cutting unit 40a and second cutting unit 40b relatively in the first direction X1 along the X-axis, and cuts the package substrate 11 along the first planned processing line 19a by causing the rotated first cutting blade 46a to cut into the package substrate 11 without causing the second cutting blade 46b to cut into the package substrate 11.

[0069] After the package substrate 11 has been cut along the first planned processing line 19a, the control unit 60 controls the orientation of the chuck table 12 around the rotation axis based on the second information so that, for example, the second planned processing line 19b becomes parallel to the X-axis (second orientation control step). That is, the control unit 60 operates the rotation drive source connected to the chuck table 12 to rotate the chuck table 12 clockwise by an angle θ2-θ1 when viewed from above.

[0070] After the second planned processing lines 19b are made parallel to the X-axis, the control unit 60 cuts the package substrate 11 along the second planned processing lines 19b by causing the rotated second cutting blade 46b to cut into the package substrate 11 (second processing step). Fig. 9 is a plan view showing how the package substrate 11 is cut along the second planned processing lines 19b, and Fig. 10 is a side view showing how the package substrate 11 is cut along the second planned processing lines 19b.

[0071] 9 shows a kerf (cut) 19c formed by cutting the first cutting blade 46a into the package substrate 11. Also, Fig. 10 shows the second cutting unit 40b as viewed from the other of the two directions along the Y axis (i.e., the opposite side to Fig. 8).

[0072] Specifically, the control unit 60, for example, operates the cutting unit moving mechanism 22 to move the second cutting blade 46b to immediately above an extension line of the second planned processing line 19b on the second direction X2 side, as shown in Fig. 9. Furthermore, the control unit 60, for example, operates the cutting unit moving mechanism 22 to move the lower end of the second cutting blade 46b to a position slightly lower than the lower end of the package substrate 11. Here, the control unit 60 moves the lower end of the first cutting blade 46a to a position higher than the upper end of the package substrate 11 so that the first cutting blade 46a does not cut into the package substrate 11.

[0073] 10, for example, the control unit 60 operates the chuck table moving mechanism 10 while rotating the second cutting blade 46b in the rotation direction R2 to move the chuck table 12 together with the package substrate 11 in the second direction X2. At this time, the control unit 60 also causes the second lower nozzle 50b and the second upper nozzle 52b to eject liquid onto the second cutting blade 46b.

[0074] As a result, the rotated second cutting blade 46b cuts into the package substrate 11, and the package substrate 11 is cut along the second planned processing line 19b. In this embodiment, the position of the lower end of the second cutting blade 46b is lower than the position of the lower end of the package substrate 11, so the package substrate 11 is cut along the second planned processing line 19b. After the package substrate 11 is cut along the second planned processing line 19b, the control unit 60 stops the movement of the chuck table 12 in the second direction X2.

[0075] In this way, the control unit 60 moves the chuck table 12 and the first cutting unit 40a and second cutting unit 40b relatively in the second direction X2 opposite to the first direction X1, and cuts the package substrate 11 along the second planned processing line 19b by causing the rotated second cutting blade 46b to cut into the package substrate 11 without causing the first cutting blade 46a to cut into the package substrate 11.

[0076] In this embodiment, the control unit 60 rotates the second cutting blade 46b in the opposite direction to the first cutting blade 46a when viewed from one side (the same side) of two different directions along the Y axis. In other words, the relationship of the rotational direction R1 of the first cutting blade 46a with respect to the first direction X1 is equal to the relationship of the rotational direction R2 of the second cutting blade 46b with respect to the second direction X2 opposite to the first direction X1.

[0077] More specifically, the relationship between the rotation direction R1 of the first cutting blade 46a and the first direction X1 at the first processing point where the first cutting blade 46a cuts into the package substrate 11 is equal to the relationship between the rotation direction R2 of the second cutting blade 46b and the second direction X2 at the second processing point where the second cutting blade 46b cuts into the package substrate 11. Therefore, variation in the quality of the cutting process between the first cutting blade 46a and the second cutting blade 46b is kept small, achieving high cutting precision.

[0078] In addition, in this embodiment, the control unit 60 supplies liquid to the first cutting blade 46a by ejecting liquid from the first outlet 54a of the first upper nozzle 52a, which opens in the first direction X1, and supplies liquid to the second cutting blade 46b by ejecting liquid from the second outlet 54b of the second upper nozzle 52b, which opens in the second direction X2.

[0079] That is, the control unit 60 supplies the liquid to the first cutting blade 46a and the second cutting blade 46b by discharging the liquid from the first discharge port 54a and the second discharge port 54b while the orientation of the first discharge port 54a relative to the first direction X1 and the orientation of the second discharge port 54b relative to the second direction X2 are the same. This further reduces variations in the quality of the cutting process, achieving even higher cutting precision.

[0080] As described above, in the method for processing a workpiece according to this embodiment, the chuck table 12 and the first cutting unit 40a and the second cutting unit 40b are moved relatively in a first direction X1 along the X-axis (processing feed axis) while the first cutting blade 46a is cut into the package substrate (workpiece) 11, thereby cutting the package substrate 11 along the first planned processing line 19a (outbound path), and then the chuck table 12 and the first cutting unit 40a and the second cutting unit 40b are moved relatively in a second direction X2 opposite to the first direction X1 while the second cutting blade 46b is cut into the package substrate 11, thereby cutting the package substrate 11 along the second planned processing line 19b (return path).Therefore, unlike conventional processing methods that only repeat cutting by relative movement in the first direction X1 (outbound path), the time for relative movement in the second direction X2 (return path) is effectively utilized, and the time required to complete cutting is shortened.

[0081] Furthermore, in the method for processing a workpiece according to this embodiment, the relationship between the rotational direction R1 of the first cutting blade 46a relative to the first direction X1 and the relationship between the rotational direction R2 of the second cutting blade 46b relative to the second direction X2 are equal, and the cutting conditions of the first planned processing line 19a and the cutting conditions of the second planned processing line 19b are equal, so that variation in the quality of the cutting is kept small and high cutting precision is achieved.

[0082] Furthermore, in the method for processing a workpiece according to this embodiment, the package substrate 11 is continuously cut on the outward and return paths of relative movement, thereby shortening the time required to complete the cutting process, so that, for example, even when information on the positions and orientations of all of the planned processing lines 19 is acquired using the camera 56 or the like to achieve higher cutting accuracy, the time required to complete the cutting process is shorter than in the conventional method in which the package substrate 11 is cut only on the outward path. Therefore, it is possible to achieve high cutting accuracy while shortening the time required to complete the cutting process.

[0083] In addition, in the method for processing a workpiece according to this embodiment, the orientation of the first outlet 54a based on the first direction X1 and the orientation of the second outlet 54b based on the second direction X2 are the same, and liquid is thereby supplied to the first cutting blade 46a and the second cutting blade 46b, thereby further reducing variation in the quality of the cutting process and achieving even higher cutting precision.

[0084] The present invention is not limited to the above-described embodiment and can be implemented with various modifications. For example, in the above-described embodiment, information (first information, second information) relating to the angle of each of the planned processing lines 19 relative to the X-axis (processing feed axis) is acquired, but when a workpiece that is unlikely to deform is to be cut, it is sufficient to acquire information relating to the angle of at least one of the planned processing lines 19 relative to the X-axis and control the orientation of the chuck table 12 around the rotation axis based on this information.

[0085] Furthermore, in the above-described embodiment, the liquid is ejected from the first outlet 54a and the second outlet 54b in a state where the orientation of the first outlet 54a based on the first direction X1 and the orientation of the second outlet 54b based on the second direction X2 are the same. However, in cases where there is a margin for error in the precision of the cutting process, the liquid may be ejected from the first outlet 54a and the second outlet 54b in a state where the orientation of the first outlet 54a based on the first direction X1 and the orientation of the second outlet 54b based on the second direction X2 are different.

[0086] Furthermore, in the above-described embodiment, the program for realizing the cutting process is stored (recorded) in the storage unit 60b in the control unit 60, but this program may be recorded, for example, on any non-transitory recording medium that can be read by a computer, etc. For example, this program may be recorded on an optical disc such as a CD (Compact Disc) that can be distributed at low cost.

[0087] In addition, the structures, methods, etc. according to the above-described embodiments and modifications can be modified as appropriate without departing from the scope of the present invention. [Explanation of symbols]

[0088] 11: Package substrate (workpiece) 13: Substrate 13a: Surface 13b: Back side 15: Device area 17: Excess area 19: Processing line (street) 19a: First processing line 19b: Second processing line 19c: Calf (cut) 21: Stage 23: Device chip 25: Sealing resin layer (mold resin layer) 27 :Structure 29: Mark 31: Dicing tape 33: Frame 2: Cutting equipment (processing equipment) 4: Base 4a: Opening 4b: Opening 4c: opening 6: Cassette table 8: Cassette 10: Chuck table moving mechanism (processing feed mechanism) 10a: Table cover 10b: Dustproof / waterproof cover 12: Chuck table 14:Frame body 14a: recess 14b: Flow path 16: Holding plate 16a:Top surface (holding surface) 18: Clamp 20:Support structure 22: Cutting unit movement mechanism (indexing feed mechanism, cutting feed mechanism) 24: Y-axis guide rail 26: Y-axis moving plate 28: Screw shaft 30: Rotation drive source 32: Z-axis guide rail 34: Z-axis moving plate 36: Screw shaft 38: Rotation drive source 40a: First cutting unit 40b: Second cutting unit 42a: First spindle housing 42b: Second spindle housing 44a: First spindle 44b: Second spindle 46a: First cutting blade 46b: Second cutting blade 48a: First cover 48b: Second cover 50a: First lower nozzle 50b: Second lower nozzle 52a: First upper nozzle 52b: Second upper nozzle 54a: 1st discharge port 54b: 2nd discharge port 56: Camera 58: Cleaning unit 60: Control unit 60a: Processing section 60b: Storage section

Claims

1. A method for processing a workpiece, which uses a processing device including: a chuck table having a holding surface for holding a workpiece and rotatable about a rotation axis intersecting the holding surface; a first cutting unit having a first spindle to which an annular first cutting blade is attached and rotatable about an axis; a second cutting unit having a second spindle to which an annular second cutting blade is attached at a position opposite to the first cutting blade and rotatable about an axis; and a processing feed mechanism that moves the chuck table, the first cutting unit, and the second cutting unit relatively along a processing feed axis, the method comprising: cutting the workpiece along a first planned processing line and a second planned processing line set on the workpiece, a holding step of holding the workpiece on the chuck table; a first processing step of cutting the workpiece along the first planned processing line by relatively moving the chuck table, the first cutting unit, and the second cutting unit in a first direction along the processing feed axis and causing the rotated first cutting blade to cut into the workpiece without causing the second cutting blade to cut into the workpiece; a second processing step after the first processing step, in which the chuck table, the first cutting unit, and the second cutting unit are moved relatively in a second direction opposite to the first direction, and the second cutting blade is rotated and cuts into the workpiece without cutting into the workpiece with the first cutting blade, thereby cutting the workpiece along the second planned processing line; After the holding step, an angle information acquiring step of acquiring first information regarding an angle formed by the first planned processing line with respect to the processing feed axis and second information regarding an angle formed by the second planned processing line with respect to the processing feed axis; a first orientation control step, after the angle information acquisition step and before the first processing step, of controlling the orientation of the chuck table around the rotation axis based on the first information so that the first planned processing line is parallel to the processing feed axis; a second orientation control step of controlling, after the first processing step and before the second processing step, an orientation of the chuck table around the rotation axis based on the second information so that the second planned processing line is parallel to the processing feed axis, A method for processing a workpiece, in which the first cutting blade and the second cutting blade are rotated so that the relationship of the rotational direction of the first cutting blade to the first direction at a first processing point where the first cutting blade cuts into the workpiece is equal to the relationship of the rotational direction of the second cutting blade to the second direction at a second processing point where the second cutting blade cuts into the workpiece.

2. The processing device further includes a first nozzle having a first outlet for discharging a liquid toward the first cutting blade, and a second nozzle having a second outlet for discharging a liquid toward the second cutting blade, In the first processing step, the first cutting blade is rotated and cuts into the workpiece while liquid is being discharged from the first discharge port onto the first cutting blade; In the second processing step, the second cutting blade is rotated and cuts into the workpiece while liquid is being discharged from the second outlet onto the second cutting blade; 2. A method for processing a workpiece as described in claim 1, wherein the liquid is ejected from the first ejection outlet and the second ejection outlet in a state where the direction in which the first ejection outlet ejects the liquid based on the first direction is the same as the direction in which the second ejection outlet ejects the liquid based on the second direction.

3. a first cutting unit having a first spindle on which an annular first cutting blade is attached and which is rotatable about an axis of rotation intersecting the holding surface; a second cutting unit having a second spindle on which an annular second cutting blade is attached at a position opposite the first cutting blade and which is rotatable about an axis of rotation; a processing feed mechanism that moves the chuck table, the first cutting unit, and the second cutting unit relatively along a processing feed axis; a first nozzle having a first outlet for discharging a liquid toward the first cutting blade; and a second nozzle having a second outlet for discharging a liquid toward the second cutting blade, a holding step of holding the workpiece on the chuck table; a first processing step of cutting the workpiece along the first planned processing line by relatively moving the chuck table, the first cutting unit, and the second cutting unit in a first direction along the processing feed axis and causing the rotated first cutting blade to cut into the workpiece without causing the second cutting blade to cut into the workpiece; a second processing step after the first processing step, in which the chuck table, the first cutting unit, and the second cutting unit are moved relatively in a second direction opposite to the first direction, and the second cutting blade is rotated and cuts into the workpiece without cutting into the workpiece with the first cutting blade, thereby cutting the workpiece along the second planned processing line, rotating the first cutting blade and the second cutting blade so that a relationship between a rotation direction of the first cutting blade and the first direction at a first processing point where the first cutting blade cuts into the workpiece is equal to a relationship between a rotation direction of the second cutting blade and the second direction at a second processing point where the second cutting blade cuts into the workpiece; In the first processing step, the first cutting blade is rotated and cuts into the workpiece while liquid is being discharged from the first discharge port onto the first cutting blade; In the second processing step, the second cutting blade is rotated and cuts into the workpiece while liquid is being discharged from the second outlet onto the second cutting blade; A method for processing a workpiece in which liquid is ejected from the first ejection port and the second ejection port in a state in which the direction in which the first ejection port ejects the liquid based on the first direction is the same as the direction in which the second ejection port ejects the liquid based on the second direction.

4. a chuck table having a holding surface for holding a workpiece and rotatable about a rotation axis intersecting the holding surface; a first cutting unit having a first spindle on which an annular first cutting blade is attached and which is rotatable about an axis; a second cutting unit having a second spindle rotatable about an axis and having an annular second cutting blade mounted at a position opposite to the first cutting blade; a processing feed mechanism that moves the chuck table, the first cutting unit, and the second cutting unit relatively along a processing feed axis; a control unit having a processing unit and a storage unit, and controlling the first cutting unit, the second cutting unit, and the processing feed mechanism in accordance with a program stored in the storage unit; a first nozzle having a first outlet for discharging liquid toward the first cutting blade; a second nozzle having a second outlet for discharging liquid toward the second cutting blade; the first nozzle and the second nozzle are arranged such that a direction of the first discharge port based on a first direction along the processing feed axis is equal to a direction of the second discharge port based on a second direction opposite to the first direction; The control unit, according to the program, A processing device that rotates the first spindle, on which the first cutting blade is attached, and the second spindle, on which the second cutting blade is attached, in opposite directions when viewed from the same side.

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