JP2678487B2 - Cutting method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial applications]

The present invention relates to a cutting method for cutting a workpiece, such as a semiconductor wafer, into a predetermined size with a rotary cutting blade formed of diamond abrasive grains.

[Prior art]

As a cutting device generally used in this type of cutting method, for example, the one disclosed in Japanese Patent Application Laid-Open No. 62-54101 by the same applicant is well known as a conventional example. This conventional cutting apparatus includes a holding means for holding a workpiece, that is, a chuck table, and a supporting member, that is, a spindle equipped with a blade for cutting the workpiece, and the chuck table is provided for the workpiece. The spindle is configured to reciprocate in the cutting direction, and the spindle reciprocates in the indexing direction for cutting the workpiece to a predetermined size.

[Problems to be solved by the invention]

In the above-mentioned conventional example, since the holding means of the work piece reciprocates only in the cutting direction of the work piece even if it gets tired, not only the stroke of the reciprocating movement of the holding means becomes large, but also the stroke is large. Therefore, there is a problem that the cutting work takes time and the workability is poor.
Further, the blade support member is configured to reciprocate only in the indexing direction for cutting the workpiece to a predetermined size, and the scale which is a signal detection source for indexing control and its drive transmission mechanism. Since the spindle and spindle are housed in a booth where heat easily accumulates, even if the scale itself is not easily affected by heat, other drive transmission mechanisms, spindles, etc. are affected by heat and the amount of movement is reduced. Cumulative error occurs, and in particular, by relying only on the support member for the movement of cutting index, the cumulative error of the movement amount is transmitted to the blade as it is, and as a result, there is a problem that the cumulative error cannot be absorbed. There is also a problem in workability. In other words, in this kind of industry, high precision and high production efficiency are required at the same time for cutting wafers, etc., but in the conventional example, it is desired to have higher precision and production efficiency from the mechanical configuration. It is difficult.

[Object of the invention]

The present invention aims to provide a cutting method in which higher precision and higher production efficiency can be expected by improving the mechanical constitution of the holding means for the workpiece and the supporting means for supporting the blade in the conventional example. .

[Means for Solving the Problems]

The cutting method of the present invention made to solve the problems of the conventional example and to achieve the above-mentioned object cuts a holding means for holding a workpiece and a workpiece held by the holding means. A cutting means, wherein the holding means and the cutting means, with respect to the cutting indexing direction of the workpiece, are moved in a direction in which they approach or separate at the same time.
In addition, the holding means and the cutting means are simultaneously moved in a direction toward or away from the cutting direction of the workpiece.

【Example】

Next, the present invention will be described in more detail with reference to the illustrated embodiment. Reference numeral 1 denotes a base on which a cutting means A for cutting a workpiece.
And holding means B for holding the workpiece. The cutting means A for the workpiece is a first movable table 3 mounted on a plurality of rails 2 arranged on the base 1, and an arm member 4 laterally attached to the movable table 3. And a blade 5 rotatably attached to the tip of the arm member. The first movable table 3 is a table having a substantially L-shape including a horizontal portion 6 and a vertical portion 7, and is mounted on the rail 2 via a guide member 8 incorporated inside the horizontal portion 6. A horizontal portion 6 is mounted on the guide member 8 through a plurality of guide rails 9 so as to be slidably engaged with the guide member 8. Therefore, the movable base 3 is arranged so as to be movable with respect to the base 1 by the rail 2 in the left-right direction in the drawing and by the guide rail 9 in the front-back direction. The movement in the left-right direction contributes to dimension indexing for cutting the workpiece to a predetermined size, and is driven by an appropriate drive source 10 such as a pulse motor. That is, the drive source 10 is arranged on the base 1, and the male screw rod 12 connected to the speed reduction mechanism 11 of the drive source and arranged substantially parallel to the rail 2 is screwed into the guide member 8. , The drive source 10
By driving, the guide member 8 moves in the left-right direction on the rail 2, and thereby the cutting means A including the movable table 3 moves in the cutting dimension indexing direction. The free end side of the male screw rod 12 is supported by an appropriate bearing member 13 in order to require the accuracy of movement. The movement in the front-rear direction is for cutting a workpiece, and like the drive source, a drive source 14 such as a pulse motor is mounted on the base 1, and a speed reduction mechanism 15 of the drive source has a male screw rod. 16 are connected, and the male screw rod 16 is arranged substantially parallel to the guide rail 9 and screwed at an appropriate position of the movable table 3. By driving the driving source 14, the cutting means A including the movable table 3 moves in the cutting direction along the guide rail 9. The arm member 4 includes a vertical portion 7 of the first movable table 3.
It is arranged so that it can move up and down. That is, the vertical portion 7
A sub-rail 17 is arranged on one side surface substantially vertically in the vertical direction, and a drive source 18 similar to the above-mentioned drive source is attached to one side end of the sub-rail 17 and is attached to a speed reduction mechanism 19 of the drive source. A male screw rod 20 is connected, and the male screw rod 20 is arranged substantially parallel to the sub rail 17 and is screwed to a sub base 21 attached to the base of the arm member 4. Then, by driving the drive source 18, the arm member 4 can be appropriately moved substantially vertically in the vertical direction. In addition, male screw rod
The free ends of 20 are supported by suitable bearing members 22. The blade 5 is rotatably attached to the tip of the arm member 4, and its specific configuration is a rotary shaft of an appropriate electric motor 23 disposed in the arm member 4.
The rotary shaft 24 is attached to the tip of the arm 24, and a flange portion 25 is integrally formed near the tip of the rotary shaft 24, and the tip of the arm member 4 is divided by a bearing member 26 that can be divided into two parts so as to sandwich the flange portion 25 from both sides. Side, and the rotary shaft 24 is substantially supported so as not to move in the axial direction at all, and the blade 5 is driven by the electric motor 23 to be rotated by the rotary shaft 24 for cutting. It is. The holding means B for holding the workpiece includes a movable base member 30, a moving table 31, and a chuck table 32, and the base member 30 is on the base 1 and at the tip position of the arm member 4. Corresponding to the above, it is reciprocally movably disposed and mounted on a plurality of rails 33 arranged in a direction orthogonal to the arm member, and the movement is similar to the movement of each mechanism or means described above and the drive source 34 and the male. It is configured to do so with a threaded rod 35. Also in this case, the male screw rod 35 is the rail 33.
As a matter of course, it is arranged substantially parallel to. And
The movement of the base member 30 is for cutting the workpiece,
The drive source 34 is driven in synchronization with the drive source 14. A moving table 31 is arranged above the base member 30 via a plurality of rails 36, and a chuck table 32 for setting and holding a workpiece is arranged on the moving table. The moving table 31 is also moved by the driving source 37 and the male screw rod 38, similarly to the driving mechanism described above, and the driving source 37 is driven in synchronization with the driving source 10. Therefore, the movement of the moving table 31 contributes to the dimension index for cutting the workpiece to a predetermined size. The chuck table 32 has a function of adsorbing and holding a workpiece as in the conventional example, and a rotating function of turning about 90 °. A signal detection mechanism for accurately controlling the amount of movement of each of the constituent parts is provided at the moving part.
That is, the first signal detection mechanism a that detects the amount of movement of the movable table 3 in the cutting dimension indexing direction, and the second signal detection mechanism that detects the amount of movement of the movable table 3 in the cutting direction (Fig. (Not shown), a third signal detecting mechanism b for detecting the amount of movement of the arm member 4 in the vertical direction, and a fourth signal detecting mechanism (not shown) for detecting the amount of movement of the base member 30 in the cutting direction. ), And a fifth signal detection mechanism c for detecting the amount of movement of the moving table 31 in the cutting dimension indexing direction.
And are arranged close to the moving part, respectively. Since these signal detection mechanisms have substantially the same configuration as that used in the above-mentioned conventional example, only one signal detection mechanism a will be described, and the other parts are denoted by the same reference numerals and the details thereof will be omitted. To do. The signal detection mechanism a is composed of a linear scale 40 having a predetermined scale arranged substantially parallel to the rail 2 inside the base 1, and a photoelectric detector 41 for reading the scale of the linear scale. Both ends of the linear scale 40 are supported by brackets 43 via elastic members 42. Further, the photoelectric detector 41 is supported by a moving member, in the case of this detecting mechanism, an arm 44 attached to the guide member 8 in an implanted state. The scale is, for example, a line having a width of 1 μm and arranged at intervals of 1 μm.

[Description of method]

Explaining the method of the present invention together with the explanation of the operation of the apparatus having the above-mentioned structure, for example, when a workpiece 50 such as a semiconductor wafer is cut, the workpiece 50 has a structure as shown in FIG.
A plurality of cutting lines are provided in a grid pattern. That is,
A large number of rows of the first set of cutting lines CLx are formed at a constant interval Px, and a second row is formed in a direction orthogonal to the cutting lines CLx.
The cutting lines CLy of the group are formed in a large number of rows with a constant interval Py. A required circuit pattern is applied to each of the large number of rectangular areas RA divided by the respective cutting lines arranged in a grid pattern, which is a general one. Such a work piece 50 is placed on the chuck table 32 and held by suction, and the cutting line and the blade 5 are aligned with each other. This alignment may be performed by using an optical detection means that has been conventionally used. After this alignment work is completed, first, the blade 5 is sequentially cut along the first set of cutting lines CLx. In this case, since the wafer may be cut over at least half or more of the thickness of the wafer instead of being completely cut and separated, the word "cutting" is used in Mushroom. Then, in the sequential cutting of the first set of cutting lines CLx, the cutting is performed from the cutting line located at the end thereof, and the blade 5 is sequentially moved to the next cutting line to perform a continuous cutting process. In this cutting process, the blade 5 cuts the cutting line CLx.
When moving between, the arm member 4 is lifted up to a predetermined height by the drive of the drive source 18, and the drive source 10 and the drive source 37 are driven in synchronization, so that the movable table 3 and the moving table are moved.
31 and simultaneously move a fixed interval Px in the cutting line CLx by half width each other and the blade 5 moves to the next cutting line.
It will be located exactly on CLx. The movable table 3 and the moving table 31 are moved by the first signal detecting mechanism a and the fifth signal detecting mechanism c, respectively, and the moving amount is shared by both, so that the moving work can be performed quickly. Also, the cumulative error is reduced. Next, at the time of cutting, the drive source 18 is driven to drive the arm member 4
Drive source 14 and drive source 34 while lowering to a predetermined position.
To drive the movable table 3 and the base member 30 in a direction approaching the cutting direction at the same time, and to move the movable table 3 and the base member 30 in excess of approximately 1/2 of the length in each cutting line CLx. And the blade 5 is the length of the cutting line CLx and the workpiece 5
The scheduled length is cut by touching 0. After the cutting along the one cutting line CLx is performed, when the blade 5 moves to the next cutting line, the arm member 4 is lifted to a predetermined height by the driving of the driving source 18, and the driving source 10 and the driving source 10 are driven. The source 37 is driven synchronously, and the movable table 3 and the moving table 31 are moved at a constant interval P in the cutting line CLx.
x are simultaneously moved by half width, and at the same time, the drive source 14 and the drive source 34 are driven in synchronization, and the movable base 3 and the base member are simultaneously driven.
By moving 30 and 30 at the same time in a direction away from each other with respect to the cutting direction, the blade 5 and the work piece 50 respectively return by exceeding approximately 1/2 of the length in the cutting line CLx, so that the return movement is performed. The amount and time are also halved, and workability in the cutting process is significantly improved. That is, the movement in the indexing direction for indexing the cutting dimension and the movement in the cutting direction for cutting are substantially mutually performed on the blade side, that is, the cutting means and the workpiece side, that is, the holding means.
By moving them by 1/2 at the same time, not only each moving time is halved to improve workability, but also the cumulative error in the indexing direction is reduced. Then, after the cutting of the first set of cutting lines CLx is completed, the chuck table 32
The same cutting process as described above is performed when 90 ° is rotated by 90 ° to sequentially cut along the second set of cutting lines CLy.

【The invention's effect】

As described above, the cutting method according to the present invention includes holding means for holding a workpiece and cutting means for cutting the workpiece held by the holding means, and the holding means and the cutting means With respect to the cutting and indexing direction of the workpiece, the indexing time is halved, workability is improved, and the workpiece side is influenced by heat by moving the workpieces in a direction toward or away from each other at the same time. Since it is difficult to receive the heat, the detecting means for controlling the movement amount thereof is always under the optimum temperature condition, and various excellent effects that the cumulative error due to the influence of heat hardly occurs are exhibited. Further, by moving the holding means and the cutting means in the direction of approaching or separating at the same time with respect to the cutting direction of the workpiece, the movement amount and time in the cutting direction are relatively reduced by half, Also has an excellent effect that workability is significantly improved.

[Brief description of the drawings]

FIG. 1 is a schematic side view in which a part of a cutting device used in the method of the present invention is cut away, and FIG. 2 is a plan view showing an example of a workpiece cut by the device. A ... Cutting means for work piece B ... Holding means for work piece 1 ... Base 2,17,33,36 ... Rail 3 ... Movable stand 4 ... Arm member 5 ... Blade, 6 ...... Horizontal part 7 …… Vertical part, 8 …… Guide member 9 …… Guide rail 10,14,18,34,37 …… Drive source 11,15,19 …… Deceleration mechanism 12,16,20,35, 38 …… Male screw rod 13,22,26 …… Bearing member, 23 …… Electric motor 24 …… Rotary shaft, 25 …… Flange part 30 …… Base member, 31 …… Moving table 32 …… Chuck table, 40… ... Scale 41 ... Photoelectric detector, 50 ... Workpiece a ... First signal detection mechanism b ... Third signal detection mechanism c ... Fifth signal detection mechanism

Claims (2)

(57) [Claims] 1. A holding means for holding a work piece, and a cutting means for cutting a work piece held by the holding means, wherein the holding means and the cutting means cut the work piece. A cutting method characterized in that the indexing directions are moved in a direction in which they approach or separate at the same time. 2. The cutting method according to claim 1, wherein the holding means and the cutting means are moved in a direction in which the workpiece is cut toward or away from the workpiece at the same time.