JP4975422B2 - Cutting equipment - Google Patents

Description

  The present invention relates to a cutting apparatus including two blades arranged to face each other.

  A wafer on which a plurality of devices such as IC and LSI are formed is ground to a predetermined thickness by grinding the back surface, and is divided into individual devices by a processing device such as a dicing device and used for electronic devices such as mobile phones and personal computers. Is done. The dicing machine is configured to reciprocate the chuck table holding the wafer in the machining feed direction, which not only increases the stroke of the reciprocating movement of the chuck table, but also increases the work time due to the large stroke. Has the problem of being bad. Thus, as a technique for improving the movement stroke, for example, there are the following proposed examples.

  First, a structure (facing dicer) in which two blades for cutting are arranged so as to face each other so that their axes are in a substantially straight line (facing dicer) is used to improve cutting efficiency by simultaneously performing two-line processing. There is something. At this time, according to Patent Document 1, a semiconductor wafer having a circular shape is simultaneously processed with the same stroke. In the structure shown in Patent Document 1, the two spindles are arranged on a common base so that the axes are substantially aligned, and the first spindle and the second spindle are independent of each other. The chuck table is movable in the X-axis direction orthogonal to the Y-axis direction when the axis direction of the spindle is the Y-axis direction, and the first spindle, the second spindle, Can move independently in the Z-axis direction orthogonal to the X-axis direction and the Y-axis direction. The conventional facing dicer has such a structure, and cuts the semiconductor wafer by moving the chuck table in the X-axis direction. It is a dual cut that simultaneously cuts using two blades of the same shape. However, the present invention can also be applied to a step cut in which the same cutting line is cut in two stages using two blades having different shapes.

  Secondly, as a configuration example of a different dicing apparatus, a chuck that can move the spindle axis in the Y-axis direction, which is the axial direction, and can also move in the X-axis direction orthogonal to the Y-axis, and further holds the wafer There is also a table in which the movement stroke is improved by making the table also movable in the X-axis direction and allowing both the spindle shaft and the chuck table to move in the X-axis direction (for example, see Patent Document 2).

Japanese Patent No. 3493282 Japanese Patent No. 2678487

  However, in the case of the facing dicer described in Patent Document 1, there are the following problems. For example, when dial cutting is performed with the facing dicer described in Patent Document 1, two blades are indexed and fed in the direction of approaching from both sides toward the center portion in order to simultaneously cut a circular wafer with the same stroke. (Or, conversely, indexing and feeding are performed in a direction away from the center toward both sides). For this reason, in the central portion of the wafer, when the interval at which the blades are closest to each other is larger than the predetermined interval that is sequentially indexed and fed, the blades may collide with each other. Therefore, in order to cut the central part while avoiding the collision between the blades, the cutting of the central part is switched to cutting with one of the blades, there are restrictions on the processing operation, and the dual cut using two blades It is not possible to maximize the benefits of.

  Also, if one blade is positioned at the center of the circular wafer and the other blade is positioned at the end of the circular wafer so that both blades are indexed and fed in the same direction, the collision of the blade operation will occur. Although there is no fear, there is a restriction in the machining operation, and a wasteful stroke is generated in the machining feed of the blade, so that the advantage of the dial cut using two blades cannot be fully exhibited.

  In addition, when processing a wafer with a TEG having a TEG (test element group) line, for example, by step-cutting using the facing dicer described in Patent Document 1, two blades are used due to the limitations of the TEG line that requires low-speed machining. It is not possible to maximize the benefits of step cut.

  None of these points can be solved even if both the two blades and the chuck table are processed and fed in the X-axis direction as shown in Patent Document 2.

  The present invention has been made in view of the above, and provides a cutting apparatus capable of maximizing the merits of dual cut or step cut when two blades arranged to face each other are provided. With the goal.

In order to solve the above-described problems and achieve the object, a cutting apparatus according to the present invention includes a chuck table that holds a workpiece, and a first blade that cuts the workpiece held by the chuck table. A second blade that is disposed so as to face the first blade and that cuts a workpiece held on the chuck table; and the first blade is arranged around an axis set in the Y-axis direction. A first spindle that is rotatably mounted and is movable up and down in the Z-axis direction with respect to the upper surface of the chuck table, and the second blade is rotatably mounted around an axis set in the Y-axis direction. And a second spindle that is movable up and down independently of the first spindle in the Z-axis direction with respect to the upper surface of the chuck table, wherein the first spindle is moved in the Y-axis direction and the Z-axis direction. In A first feeding means for processing feed the interlinked X-axis direction, and the first spindle the second spindle in the X-axis direction and the second feeding means for processing feed is independent, the first First index feeding means for indexing and feeding one spindle in the Y-axis direction; and second index feeding means for indexing and feeding the second spindle in the Y-axis direction independently of the first spindle ; It is characterized by providing.

Also, in the above SL invention, the first feeding means is mounted on the first X Jikumoto stand disposed for movement in the Y-axis direction on the fixed base, said second machining feed The means is mounted on a second X-axis base disposed on the fixed base so as to be movable in the Y-axis direction, and the first indexing means is the first index feeding means with respect to the fixed base. The first spindle is indexed and moved by moving the X-axis base in the Y-axis direction, and the second index-feeding means moves the second X-axis base with respect to the fixed base in the Y-axis direction. It is preferable that the second spindle is indexed and fed by being moved to .

  According to the cutting device of the present invention, the first and second spindles having the first and second blades can be independently processed and fed in the X-axis direction, and are independently indexed and fed in the Y-axis direction. Since it is possible, the first and second spindles can be processed with respect to the wafer at different processing feed speeds and strokes and are not restricted by the other spindle. It is possible to perform an optimum operation for wafer processing every time, and therefore, it is possible to maximize the advantages of dual cut and step cut when two blades arranged to face each other are provided. .

  DESCRIPTION OF THE PREFERRED EMBODIMENTS A cutting apparatus that is the best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic front view showing the main part of the cutting device of the present embodiment, FIG. 2 is a plan view thereof, and FIG. 3 is a schematic side view seen from the direction of arrow A in FIG. is there. The cutting apparatus 1 according to the present embodiment includes a chuck table 11 that holds a workpiece 10, first cutting means 20 a and second cutting means 20 b that cut the workpiece 10 held on the chuck table 11. Is provided. The first cutting means 20a includes a first blade 21a formed of a disk-shaped blade, and a first spindle 22a on which the first blade 21a is rotatably mounted around an axis. The axis of the spindle 22a is set in the Y-axis direction which is the index feed direction. The second cutting means 20b has a second blade 21b made of a disk-shaped blade, and a second spindle 22b on which the second blade 21b is rotatably mounted about its axis. The axis of the spindle 22b is set in the Y-axis direction. Here, the first blade 21a and the second blade 21b, which are rotatably mounted around the axial centers of the first and second spindles 22a and 22b, are disposed so as to face each other in the Y-axis direction. It is configured as a single dicer. The first blade 21a and the second blade 21b may be the same type for dual cut or different types for step cut.

  The chuck table 11 is provided so as to be fixed in position, and is configured to hold the workpiece 10 on the mounting surface by suction means (not shown). Further, the chuck table 11 is configured to be rotatable by a rotation mechanism (not shown) in order to rotate the workpiece 10 by 90 degrees.

  The cutting apparatus 1 according to the present embodiment includes a fixed base 12 that is formed in a gate shape that crosses over the chuck table 11 in the Y-axis direction and is fixed to the apparatus main body. The first elevating feed means 30a, the second elevating feed means 30b, the first machining feed means 40a, the second machining feed means 40b, the first index feed means 50a, and the second index feed means 50b are provided. .

  The first and second elevating and feeding means 30a and 30b are configured so that the first and second spindles 22a and 22b of the first and second cutting means 20a and 20b are independently Z with respect to the upper surface of the chuck table 11. The first and second blades 21a and 21b are moved up and down in the axial direction to cut or separate the workpiece 10 from each other. The first and second elevating and feeding means 30a and 30b are movable on the X-axis direction and fixed on the Z-axis direction on the vertical surfaces of the first and second Z-axis bases 31a and 31b. On the other hand, ball screws 32a and 32b arranged in the Z-axis direction, pulse motors 33a and 33b connected to one ends of the ball screws 32a and 32b, and the first and second Z parallel to the ball screws 32a and 32b. It is composed of a pair of guide rails (not shown) formed on the vertical surfaces of the shaft bases 31a and 31b. The ball screws 32a and 32b are provided on holders 34a and 34b for holding the first and second spindles 22a and 22b. A nut (not shown) is screwed. The ball screws 32a and 32b are driven and rotated by forward and reverse pulse motors 33a and 33b, and the holders 34a and 34b are guided by guide rails to reciprocate in the Z-axis direction. The spindles 22a and 22b are configured to be moved up and down independently in the Z-axis direction.

  The first and second machining feed means 40a and 40b are arranged so that the first and second spindles 22a and 22b of the first and second cutting means 20a and 20b are in the X-axis direction orthogonal to the Y-axis direction and the Z-axis direction. Are to be processed and fed independently. The first and second processing feed means 40a and 40b are first and second X-axis bases which are movable on the common fixed base 12 in the Y-axis direction and fixedly arranged in the X-axis direction. Mounted on 41a and 41b, ball screws 42a and 42b disposed in the X-axis direction with respect to the lower surfaces of the first and second X-axis bases 41a and 41b, and ball screws 42a and 42b It comprises pulse motors 43a and 43b connected to one end and a pair of guide rails 44a and 44b formed on the lower surfaces of the first and second X-axis bases 41a and 41b in parallel with the ball screws 42a and 42b. The nuts (not shown) provided on the first and second Z-axis bases 31a and 31b holding the first and second spindles 22a and 22b are screwed into the ball screws 42a and 42b. The ball screws 42a and 42b are driven and rotated by pulse motors 43a and 43b that can freely rotate in the forward and reverse directions, and accordingly, the first and second Z-axis bases 31a and 31b are guided by the guide rails 44a and 44b and the X-axis. The first spindle 22a and the second spindle 22b are reciprocally moved in the direction, and are independently processed and fed in the X-axis direction.

  The first and second indexing and feeding means 50a and 50b are for indexing and feeding the first and second spindles 22a and 22b of the first and second cutting means 20a and 20b independently in the Y-axis direction. Is. The first and second indexing and feeding means 50a and 50b include ball screws 51a and 51b disposed in the Y direction with respect to the vertical surface of the fixed base 12, and a pulse motor connected to one end of the ball screws 51a and 51b. 52a, 52b and a pair of guide rails (not shown) formed on the vertical surface of the fixed base 12 in parallel with the ball screws 51a, 51b. The ball screws 51a, 51b have first and second X-axis bases. Nuts (not shown) provided on holders 53a and 53b for holding the bases 41a and 41b are screwed together. The ball screws 51a and 51b are driven and rotated by forward and reverse pulse motors 52a and 52b, and the holders 53a and 53b are guided by guide rails to reciprocate in the Y-axis direction. The spindles 22a, 22b are indexed and fed independently in the Y-axis direction via the first and second X-axis bases 41a, 41b.

  FIG. 4 is a plan view showing an example of the workpiece 10 held on the chuck table 11. The workpiece 10 includes a wafer W having a circular shape such as a semiconductor wafer attached to the surface of an adhesive tape T attached to an annular frame F. As shown in FIG. 4, the wafer W is divided into a plurality of rectangular areas by a plurality of division lines S formed in a lattice pattern on the surface Wa, and a device D such as an IC or LSI is formed in the divided rectangular areas. It has been done.

  Using the cutting apparatus 1 configured as described above, a dual-cut method using, for example, a circular wafer W as shown in FIG. 4 as the workpiece 10 and the first and second blades 21a and 21b of the same type. When cutting is performed, the optimum conditions can be achieved by appropriately controlling the movement of the first and second spindles 22a and 22b in the X-axis, Y-axis, and Z-axis directions.

  An example of operation control of the first and second spindles 22a and 22b when the wafer W is dual-cut will be described with reference to FIGS. FIG. 5 is a schematic front view showing an example of positioning of the first and second spindles 22a and 22b, and FIG. 6 is a schematic plan view showing an example of a cutting result of the wafer W. First, as shown in FIG. 5A, the wafer W that is the workpiece 10 held on the chuck table 11 is independently indexed by the first and second indexing and feeding means 50a and 50b. The first blade 21a is positioned on the planned division line S at the center of the wafer W, and the second blade 21b is positioned on the planned division line S at the right end of the wafer W. Then, the first and second spindles 22a and 22b are lowered by the independent lift feed by the first and second lift feed means 30a and 30b, and independent by the first and second processing feed means 40a and 40b. The first and second spindles 22a and 22b are processed and fed in the X-axis direction by the machining feed, and the cutting operation for the division planned line S is executed simultaneously. Thereby, the division | segmentation scheduled line S of the center part and right end part of the circular wafer W is cut, and the cutting groove K as shown to Fig.6 (a) is formed.

  At this time, the length (the stroke length in the X-axis direction) differs between the planned division line S at the center of the wafer W and the planned division line S at the end, but in the cutting device 1 of the present embodiment, the first The first and second spindles 22a and 22b can be independently fed in the X-axis direction by the second machining feed means 40a and 40b. The first and second spindles 22a and 22b can be fed back in the X-axis direction by a stroke corresponding to the length of each line S, and can be moved backward. Stroke is not wasted during machining. Incidentally, in the case of Patent Document 1 or the like, the first and second spindles are integrally processed and fed in the X-axis direction, so the second spindle on the end side is also the first on the center side. Processing is fed with the same stroke as that of the spindle, resulting in a useless stroke as shown by a broken line in FIG.

  Thereafter, as shown in FIGS. 5B and 5C, the first and second indexing feeding means 50a and 50b perform independent indexing and feeding with the first and second spindles 22a and 22b spaced apart. The first and second blades 21a and 21b are sequentially indexed and fed to the left division line S, and the first and second spindles are independently fed by the first and second machining feed means 40a and 40b. 22a and 22b are processed and fed in the X-axis direction, and the cutting operation for the planned division line S is executed in parallel. Thereby, the division | segmentation scheduled line S of the circular wafer W is cut sequentially, and the cutting groove K as shown to FIG.6 (b) (c) is formed. Also in this case, it is understood that a useless stroke as shown by a broken line does not occur.

  At this time, the length (stroke) of the division line S to be cut by the first and second blades 21a and 21b is different, and the processing time is different between the first and second blades 21a and 21b. The first and second index feeding means 50a and 50b independently index and feed the first and second spindles 22a and 22b toward the next division line S as soon as the division line S is cut. . That is, on the first blade 21a side, indexing feed is performed in order to sequentially perform cutting of the longer planned division line S at the center of the circular wafer W and cutting of the shorter planned division line S at the left end. The timing is controlled so as to be late at the beginning but earlier as it goes toward the left end. On the other hand, in the case of the second blade 21b side, on the other hand, since the cutting of the short planned dividing line S at the right end of the circular wafer W is sequentially performed from the cutting of the planned dividing line S in the central view, the indexing is performed. The feeding timing is controlled so as to be early at first but later toward the center. Thereby, the cutting operation by the first and second blades 21a and 21b proceeds in parallel from the beginning to the end without causing a loss time between the first and second blades 21a and 21b.

  As described above, according to the present embodiment, when the circular wafer W is cut by the dual cut method, there is no possibility of collision between the first and second blades 21a and 21b, and it is wasteful. It is possible to cut efficiently without causing any X-axis direction stroke or loss time. That is, since the first and second spindles 22a and 22b are not restricted by the operation of the other spindle, the first and second spindles 22a and 22b are cut in half of the area of the circular wafer W. The most efficient dual cut becomes possible by causing the first and second spindles 22a and 22b to perform the optimum operation for wafer processing.

  FIG. 7 is a schematic plan view showing another example of the wafer W ′ to be processed. This wafer W ′ is a wafer with TEG in which TEGs (test element groups) for inspection are aggregated and arranged on a predetermined division line S every predetermined number of division lines. In FIG. 7, only the scheduled division lines S and TEG are shown in a simplified manner. In such a wafer W ′ with TEG, the TEG portion is cut by half-cutting the TEG portion on the surface with a slightly wider blade for surface film processing at a lower feed rate and then cutting with a full-cut blade. A step cut that increases the depth and makes a full cut is required.

  Using the cutting apparatus 1 configured as described above, a workpiece 10 having, for example, a circular WEG with a TEG as shown in FIG. 7 and different first and second blades 21a and 21b (first When cutting by the step-cut method using one blade 21a, for example, a half-cut blade having a width of 50 μm and a second blade 21b, for example, a full-cut blade having a width of 40 μm, It can be performed under optimum conditions by appropriately controlling the movement of the second spindles 22a and 22b in the X-axis, Y-axis, and Z-axis directions.

  An example of operation control of the first and second spindles 22a and 22b in the case of step-cutting the wafer W ′ with TEG will be described with reference to FIGS. FIG. 8 is a schematic front view showing an example of positioning of the first and second spindles 22a and 22b, and FIG. 9 is a schematic explanatory diagram showing an example of operation control in time series. Here, it is assumed that the TEG is disposed on the division planned lines S every four lines, for example.

First, as shown in FIG. 8 (a), the first blade 21a is moved by the index feed by the first index feed means 50a to the wafer W 'which is the workpiece 10 held by the chuck table 11. It is positioned on the planned division line (first TEG line) S ₁ having the TEG at the right end of the wafer W ′. The first blade 21a is lowered to the half-cut position by the elevation feed by the first elevation feed means 30a, and the first spindle 22a is moved at a low speed in the X-axis direction by the machining feed by the first machining feed means 40a. The cutting operation (half cut) is performed on the division planned line (first TEG line) S ₁ . At this time, the second blade 21b side is in a standby state.

When the half-cut is completed dividing line for (initial TEG line) S _1, the indexing of the first indexing means 50a, the dividing lines (right having TEG a first blade 21a to the next wafer W' positioned in the second TEG line) S ₅ from. The first blade 21a is lowered to the half-cut position by the elevation feed by the first elevation feed means 30a, and the first spindle 22a is moved at a low speed in the X-axis direction by the machining feed by the first machining feed means 40a. machining feed is to execute the dividing line (second from the right of the TEG line) cutting operation to S ₅ (half-cut).

Such division lines in parallel with the half-cut operation for (second TEG line from the right) S _5, as shown in FIG. 8 (b), the indexing of the second indexing means 50b, the second The blade 21b is positioned on a division planned line (first TEG line) S ₁ having a half-cut TEG of the wafer W ′. Then, the second blade 21b is lowered to the full cut position by the elevation feed by the second elevation feed means 30b, and the second spindle 22b is normally fed in the X-axis direction by the machining feed by the second machining feed means 40b. Processing is performed at a speed, and a cutting operation (full cut) is performed on the division planned line (first TEG line) S ₁ . Subsequently, the second spindle 22b is moved back in the X-axis direction, and the second blade 21b is moved to the next scheduled division line S ₂ having no TEG of the wafer W ′ by the index feed by the second index feed means 50b. Position. Then, the second blade 21b is lowered to the full cut position by the elevation feed by the second elevation feed means 30b, and the second spindle 22b is normally fed in the X-axis direction by the machining feed by the second machining feed means 40b. rate is machining feed, to perform a cutting operation (full-cut) for dividing line S _2. During the low-speed half-cut operation on the planned division line (the second TEG line from the right) S _{5, the} cutting operation (full cut) at the normal feed speed is repeated in the same manner for the planned division lines S ₃ and S _4. .

  Similarly, with respect to the subsequent division line S, the division line S having the TEG is half-cut while the first blade 21a is processed and fed at a low speed, and the second blade 21b is fed at the normal feed speed. As shown in FIG. 8 (c), a full cut of a plurality of lines is sequentially performed while processing and feeding, and the final division line S on the left end side is fully cut with the second blade 21b as shown in FIG. A series of cutting operations on is completed.

  As described above, according to the present embodiment, when the wafer W ′ with TEG is cut by the step cut method, the first blade 21a performs the half cut by the desired low-speed machining feed only on the TEG line, and the second While the blade 21b is half-cut by low-speed machining feed, it is possible to perform a full cut of a plurality of lines to be divided at a normal machining feed speed in parallel. That is, the first and second spindles 22a and 22b are not subject to restrictions such as processing feed speed and index feed due to the operation of the other spindle. The most efficient step cut can be performed by performing the operation optimal for the full cut independently and in parallel.

  By the way, in the conventional step-cut method, the chuck table is processed and fed in the X-axis direction with respect to the half-cut blade and the full-cut blade, so the full-cut blade also has the same low speed during the processing of the TEG line. There is a restriction that a full cut must be made by processing feed. For this reason, for example, after half-cutting only the TEG line on the wafer with low-speed machining feed with a half-cut blade, it is necessary to perform special machining such as sequentially cutting all the lines to be divided with the full-cut blade. However, it takes a long processing time, and the advantages of step cutting using two blades cannot be maximized.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the present embodiment, first and second X-axis bases 41a and 41b that are movable in the Y-axis direction are provided on the common fixed base 12, and the first and second X-axis bases 41a and 41b are provided. By mounting the first and second processing feed means 40a and 40b on the top, the feed in the X-axis direction is performed independently and the feed in the Y-axis direction is performed independently. The fixed base 12 is provided with first and second Y-axis bases movable in the X-axis direction, and the first and second index feeding means are mounted on the first and second Y-axis bases. Thus, the feed in the Y-axis direction may be performed independently and the feed in the X-axis direction may be performed independently. However, mounting the first and second machining feed means 40a and 40b on the first and second X-axis bases 41a and 41b as in the present embodiment reduces the load during machining feed. be able to.

It is a schematic front view which shows the principal part of the cutting device of embodiment of this invention. It is a top view of FIG. It is the schematic side view seen from the arrow A direction in FIG. It is a top view which shows an example of the workpiece hold | maintained on a chuck table. It is a schematic front view which shows the example of positioning of a 1st, 2nd spindle. It is a schematic plan view which shows the example of a cutting result of the wafer W. It is a schematic plan view which shows the other example of wafer W 'used as a to-be-processed object. It is a schematic front view which shows the example of positioning of a 1st, 2nd spindle. It is a schematic explanatory drawing which shows an example of operation control in time series.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Workpiece 11 Chuck table 12 Fixed base 21a 1st blade 21b 2nd blade 22a 1st spindle 22b 2nd spindle 40a 1st process feed means 40b 2nd process feed means 41a 1st X-axis Base 41b Second X-axis base 50a First index feed means 50b Second index feed means

Claims (1)

A chuck table for holding a workpiece, a first blade for cutting the workpiece held on the chuck table, and a workpiece held on the chuck table disposed to face the first blade. A second blade that cuts a workpiece, and a first blade that is rotatably mounted around an axis set in the Y-axis direction and is movable up and down in the Z-axis direction with respect to the upper surface of the chuck table. And the second blade is rotatably mounted around the axis set in the Y-axis direction, and can be moved up and down independently of the first spindle in the Z-axis direction with respect to the upper surface of the chuck table. A second spindle, and a cutting device comprising:
First machining feed means for machining and feeding the first spindle in the X-axis direction orthogonal to the Y-axis direction and the Z-axis direction;
Second machining feed means for machining and feeding the second spindle in the X-axis direction independently of the first spindle ;
First index feeding means for indexing and feeding the first spindle in the Y-axis direction;
Second index feeding means for indexing and feeding the second spindle in the Y-axis direction independently of the first spindle ;
A cutting apparatus comprising:

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