JPH01176512A - Cutting device for column-shaped material - Google Patents

Abstract

PURPOSE:To eliminate the necessity of having a slice base additionally and also eliminate the generation of defects such as cracks or the like at the time of cutting by suction retaining a cutting side end surface by means of a suction retaining means before starting the cutting and continuing the cutting while said state is retained until the completion of cutting. CONSTITUTION:An inner spherical blade type blade 12 is revolved at high speed, and an ingot 10 is cut by a cutting and feeding table 28, or in other words, moving the ingot 10 in the arrow direction A. During the cutting, a recovering tray 24 sucks and retains the end surface on the cutting side of the ingot 10 so as not to generate cracks or the like on a wafer and moves together with the cutting and feeding table 28. A slice base provided additionally to the column-shaped material by means of a bonding agent or the like can be eliminated by having said cutting device, and also a plurality of sliding components (suction pads 35, pressing pins) can be provided without any spaces on the end surface, which eliminates the generation of defects such as cracks or the like until the completion of cutting even if a fragile material such as an extremely thin wafer or GaAs or the like is used.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cutting device for columnar materials, and particularly for cutting columnar materials (hereinafter referred to as ingots) such as silicon, which is a material for manufacturing semiconductor devices, with a rotating blade. The present invention relates to a cutting device for columnar material.

[Conventional technology]

Ingots such as silicon used in semiconductor devices are brittle, so when the ingot is cut into flakes with a rotating blade, the ingots may crack and chip just before the cutting is completed, causing the ingots to be separated. As a result, the outer periphery of the wafer that has been cut into flakes is damaged.
- There is a problem that the number of semiconductor elements obtained from one wafer is significantly reduced.

In order to solve this problem, a part of the side of the ingot was covered with a waste material (such as carbon) along the length of the ingot.
(hereinafter referred to as slice base) is attached by gluing etc.
A cutting method is adopted in which cutting is performed from the side opposite to the surface to which the slice base is adhered, and the slice base is cut last (see, for example, Japanese Patent Laid-Open No. 61-65749).

[Problems to be Solved by the Invention] According to the above cutting method, although the problem of ingot and wafer loss can be solved to a certain extent, it is necessary to prepare the slice base in advance, attach it, and remove the slice base from the wafer after cutting. In addition, it is necessary to select a slicing base made of a material that does not adversely affect the cutting edge of the blade.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a cutting device for columnar material that does not require the addition of a slicing base and does not cause defects such as cracks during cutting.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention provides a cutting device for columnar material that rotates a blade to cut a columnar material whose base end is fixed, and the end surface of the cut side is suction-held by a suction-holding means before the start of cutting. It is characterized by cutting while maintaining that state until the cutting is completed.

[Effect]

According to the present invention, the end face of the columnar material on the cutting side is fixed by suction during cutting. When fixing by suction, we focused on the fact that the cut side end face of the columnar material is not necessarily parallel or flat, and made it possible to advance and retreat multiple sliding members facing the cut side end face. The tip of each sliding member is arranged so as to be along the cut-side end surface of the columnar material without any gap, and suction is applied so that the end surface comes into contact with the tip of the sliding member. Each sliding member is fixed so that it cannot move forward or backward with the tip of each sliding member along the end surface. Here, each sliding member is simultaneously fixed by one cylinder portion or the like provided approximately at the center thereof. That is,
Clamp pins are arranged radially from the cylinder toward each sliding member, and when the piston in the cylinder moves, the movement of the piston is transmitted to the clamp pin via a predetermined connecting member. Each sliding member is fixed simultaneously by the pressing force from the clamp pin.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the cutting apparatus for columnar material according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a perspective view of a cutting device for columnar material according to the present invention. This device includes an inner peripheral blade type blade 12 having a blade part 12A formed on the inner peripheral edge for cutting the columnar material (ingot) 10, a collection conveyor 16 for transporting the cut wafers to a wafer storage cassette 14, etc. A main body 18 having a base end side of the ingot 10 is fixed, and the ingot 1
an arm equipped with a support 22 equipped with an indexing slider 20 that moves the wafer in the vertical direction, and a collection tray 24 that suctions and holds the cut end surface of the ingot 10 during cutting and receives and transfers the wafer to the collection conveyor 16 after cutting. 26 and the like.

The internal blade type blade 12 is connected to the rotating body 1 as shown in FIG.
The ingot 10 is cut by moving the cutting feed table 28, that is, the ingot 10 in the six directions of arrows. Also, the thickness of the wafer cut in this way is
It is determined by the amount of downward feeding of the ingot 10 by the index slider 20.

On the other hand, during the above-mentioned cutting, the collection tray 24 moves together with the cutting feed table 28 while sucking and holding the end face of the ingot 10 on the cutting side so that the wafer is not cracked until the cutting is completed. Note that the details of this collection tray 24 will be described later. Further, after cutting is completed, the collection tray 24 is rotated 180 degrees from the state shown in FIG. 2, and then the arm 26 is raised and the wafer is transferred to the collection conveyor 16 by a wafer unloader device (not shown).

Next, the collection tray 24 will be explained in detail.

3 is a plan view of the recovery tray 24, FIG. 4 is a sectional view taken along the line AA in FIG. 3, and FIG. 5 is a sectional view taken along the line BB in FIG. 3. As mentioned above, this collection tray 24 has the function of suctioning and holding the end face of the ingot 1o on the cutting side during cutting, and as shown in FIG. They are arranged at equal intervals on the same circumference so as to be evenly located over the entire surface of the wafer in accordance with the diameter.

FIG. 8 is an enlarged view of the vacuum chuck 30 surrounded by the dashed line in FIG. 4. This vacuum chuck 30 is
A cylinder 31 which is mainly housed and fixed in the collection tray 24, and a vacuum rod 3 having a pad support ball 32 at one end.
3 is implanted into the piston 34 and the pad support ball 32
The suction pad 35 is supported by a suction pad 35.

The pad support ball 32 is made of a sphere with a vacuum hole formed in the center, and the suction pad 35 is attached to the pad support ball 32 by sandwiching the pad support ball 32 between two conical members 35B and 35C. It is being

That is, a spherical bearing is configured between the pad support ball 32 and the suction pad 35, and the suction pad 35 can tilt in all directions. FIG. 9 shows a state in which the suction pad 35 is tilted by 5 degrees.

A set screw 37 and a clamp pin 56 are fitted into the outer periphery of the cylinder 31, so that the cylinder 31 is fixed to the collection tray 24, and the piston 34 can be clamped by the pressing force of the clamp pin 56, which will be described later. ing.

A vacuum hole 34A communicating with the vacuum rod 33 is formed in the piston 34, and the vacuum hole 34A of each piston 34 communicates with the vacuum tube 34B as shown in FIG.
The starting and ending parts are vacuum holes 3 formed on the collecting tray side.
4C (see FIG. 5 and FIG. 6, which is a sectional view taken along line CC in FIG. 5), and communicates with a vacuum hole (not shown) on the arm 26 side. Further, a vent hole 34D is formed in the piston 34 to keep the pressure at the top and bottom of the piston the same, thereby preventing the occurrence of hysteresis in the suction pad 35 due to minute air leaks from the spherical bearing.

Further, the tip of the suction pad 35 is provided with a porous pad 35A whose upper end is a flat surface, so that the suction force does not deform the wafer when the wafer is suctioned. Furthermore, a bellofram 36 is disposed between the suction pad 35 and the cylinder 31. Furthermore, 39.
40.41 is the 0 ring, and 42A is the packing.

Next, the operation of the vacuum chuck 30 having the above configuration will be explained.

First, before starting cutting of the ingot 10, the collection tray 24 is moved so that the six vacuum chucks 30 face the end surface of the ingot 10 on the cutting side. And collection plate 2
4, the vacuum pump (not shown) is turned on, and the arm 26, the vacuum hole 34c1 of the collecting tray 24, the vacuum chineph 34B, the vacuum hole 34A of the piston 34, the vacuum rod 33, and the support ball 32 are opened. Through this, negative pressure is generated at the tip of the suction pad, and an air supply hole 42 (Fig. 3) is provided at the bottom of the piston 34.
More compressed air is supplied to raise the piston 34. Note that FIGS. 8 and 9 show the state in which the piston 34 has risen to the uppermost end.

While the piston 34 is rising, the six suction pads 35 rise and tilt according to the shape of the ingot end surface, and adsorb the ingot end surface while being in contact with the end surface without any gaps. In this state, the entire collection pan and the collection pan 24 are
Deflection has occurred in the arm 26 that supports the.

In this state, the compressed air supplied to the lower end side of the piston 34 is released to the atmosphere. As a result, the deflection of the collecting tray 24 and the like is eliminated, and the state becomes undistorted.

That is, the suction pad 34 is stuck to the ingot end face only by suction force, and no pressing force or tensile force acts on the ingot end face.

Thereafter, the side of the cylinder 31 is pressed by the clamp pin 56 to fix the piston 34.

As mentioned above, since the end face of the ingot 10 on the cutting side is fixed, the wafer cut out does not wobble during cutting, and since no pressing force is applied from the collecting tray 24 side, the wafer is cut without chipping. can be completed. Note that since the suction pads 35 are configured to be swingable, there is a concern that the wafer may wobble during cutting, but each suction pad 35 is made unable to move forward or backward, and a large number of suction pads 35 are arranged on the suction end surface. Since they are evenly distributed, they can be fixed as a whole and the wafer will not wobble. Further, a porous pad 35A is provided at the upper end of the suction pad 35, and the suction surface thereof is flat, so that stress due to suction force does not act on the wafer.

Next, a clamp device for fixing each piston 34 will be explained.

FIG. 10 shows the clamping device 50 surrounded by the dashed line in FIG.
FIG. 11 is a sectional view taken along line DD in FIG. 10. This clamp device 50 mainly includes a cylinder portion 51 formed in the center of the collection tray 24, a hollow first piston 52 that slides inside the cylinder portion 51,
A second piston 5 sliding inside this first piston 52
3, the first piston 52 and the second piston 53
a first ring 54 and a second ring pressed respectively by
a first ring 55, six clamp pins 56 slidably penetrating around the cylinder portion 51 and arranged radially at equal intervals, and a first ring 54.
and the three clamp pins 56; and the second plate 58, which is disposed between the second ring 55 and the other three clamp pins 56. It is configured.

A stopper 6° is disposed at the lower end of the second piston 53, the second ring 55 is disposed between the second piston 53 and the stopper 60, and the first ring 54 is disposed between the second piston 53 and the stopper 60.
is arranged between the piston 52 and the stopper 60.

Grooves 54A and 55A are formed around the first ring 54 and the second ring 55 for hooking one ends of the first plate 57 and the second plate 58, and similarly, after the clamp pin 56, grooves 54A and 55A are formed. A groove portion 56A is formed at each end to hold the other ends of the first plate 57 and the second plate 58.

Further, as described above, the tips of the six clamp pins 56 are fitted into the outer circumference of each cylinder 31 of the six vacuum chucks 3o (see FIGS. 11 and 6).

Note that the first ring 54 is formed with a hole 54B through which the second plate 58 passes, and between the cylinder portion 51 and the first piston 52 and between the first piston 52 and the second piston. 53, gaskets 62 and 63 are provided, respectively.

Next, the operation of the clamp device 50 having the above configuration will be explained.

As described above, when the recovery tray 24 moves to a position facing the cut end surface of the ingot 10, the air supply holes 42 are formed at the bottom of the pistons 34 of the six vacuum chucks 30.
(FIG. 3), compressed air is supplied to the lower portions of the first piston and the second piston 53 of the clamp device 50 at the same time.

As a result, the first piston 52 and the second piston 5
3 is pushed up, and at the same time, the stopper 60 connected to the second piston 53 is raised, so that the first ring 54 and the second ring 55 are also pushed up. As these rings 54 and 55 rise, the ring hanging sides of the first plate 57 and the second plate 58 are lifted,
As a result, the pressing force on the cylinder 31 by the clamp pin 56 is released, and the piston 34 of the vacuum chuck 30
becomes able to slide inside the cylinder 31.

After that, as mentioned above, 6 vacuum chucks 30
After the end face of the ingot is attracted by the clamping device 50, the pistons 34 of each vacuum chuck 30 are simultaneously fixed by the clamping device 50.

That is, when fixing the piston 34 of the vacuum chuck 30, the air supply hole 43 and the air supply path 43A
Compressed air is supplied to the upper portions of the first piston 52 and the second piston 53 of the clamping device 50 through (see FIGS. 3 and 5).

Note that the lower portions of the first piston 52 and the second piston 53 are open to the atmosphere.

As a result, the first piston 52 and the second piston 5
3 are each independently pushed down, and the first ring 5
4 and the second ring 55 downward. The first ring 54 and the second ring 55 push six clamps 56 arranged radially through the first plate 57 and the second plate 58, respectively, and these clamp pins 56 push six clamps 56 through the first plate 57 and the second plate 58, respectively. The piston 34 in each cylinder 31 is clamped by pressing the side of each cylinder 31 of the vacuum chuck 30 .

Note that when the clamp is finished, the first plate 57 and the second plate 57
The inclination of plate 58 approaches horizontal, and plate 57.
Plate 57.5 for the amount of movement on the ring hooking side of 58
The amount of movement of the clamp pin 8 on the clamp pin latching side becomes minute, and a large pressing force acts on the clamp pin 56 due to this boosting mechanism. In addition, the first piston 52 and the first ring 54
, the first plate 57, the second piston 53, the second ring 55, and the second plate 57 each operate independently, and each clamps the piston 34 of the vacuum chuck 30 via the three clamp pins 56. The double structure allows for reliable clamping.

FIG. 12 is a schematic diagram showing another embodiment of the cutting device for columnar material according to the present invention. In this device, an ingot 10 is mounted on a slidable work table 60 via a spacer 61, and the body portion (base portion) of the ingot 10 is immovably fixed by a suitable clamper 62. Although the illustrated clamper 62 is of a type that clamps and fixes the ingot 10, known means such as a type of gripping or clamping one end side of the ingot can be used.

Reference numeral 63 denotes an internal blade type blade stretched on a cylindrical spindle (not shown). The cylindrical spindle is known for use in slicing devices equipped with internal blades (see FIG. 2). The blade 63 in the example shown in the figure schematically shows the upper half of the cross section, and since it actually has a donut shape, the lower half of the blade is placed below the table 60 at appropriate intervals in symmetrical relation to the upper half. It will exist.

64 is a vacuum holder device that grips the end surface of the ingot 10 to be cut, and the device body 65 has a cylindrical outer shape, and a relatively flexible lip 65A made of rubber or the like is integrally formed around the opening on the tip side. It is provided. The size of the opening of the main body 11 corresponds to the size of the portion of the ingot 10 to be gripped by suction. Further, 65B is a vent hole that communicates with a vacuum pump (not shown) to reduce the pressure in the inner space of the holder device main body 11 when necessary. The vacuum holder device main body 65 is supported by its support base B and slides manually or automatically on the table 60, and the support base B can be fixed at any position by generally known means. There is.

Reference numeral 66 denotes a plurality of presser pins, which are appropriately disposed so as to be included in the holder device main body 65, and which are movable in the axial direction and come into contact with the cutting side end face of the ingot 10 when necessary, and the end face (grip part) Each pin is individually adjusted to move forward or backward according to the shape.

Note that each pin is biased toward the ingot by a spring (not shown).

In addition, inside the holder device main body 65, there are
A clamping device having the same configuration as the clamping device shown in the figure is included, and each presser pin 66 is fixed at a required forward/backward position by this clamp device.

FIG. 13 is a cross-sectional view showing another embodiment of the collection tray applied to the cutting device for columnar material according to the present invention, and is shown with respect to the same cross section as the aforementioned collection tray 24 (FIG. 4). There is. As shown in the figure, this collection tray 70 has a configuration between the collection tray 24 and the path described above, but the suction pad 74 of the vacuum chuck 72 is supported via a spherical bearing structure, and the piston The difference is that it is directly fixed on the 76. In addition, 78 is a ventilation path for vacuum.

The collection tray 70 having the above configuration is effective when the cut end surface of the columnar material has a very high degree of flatness (for example, when grinding the end surface), and according to this, the spherical bearing structure in the absorbent pad part is unnecessary. Therefore, the unit configuration can be simplified.

〔Effect of the invention〕

As explained above, according to the cutting device for columnar material according to the present invention, it is not necessary to attach the slice base to the columnar material with an adhesive or the like, thereby reducing the material cost of the slice base itself and the adhesion and peeling of the slice base. (Disposal) process can be reduced. In addition, when holding the cut end face of the columnar material by suction, a plurality of sliding members (suction pads, suction pads,
The presser pins can be attached without any gaps, thereby preventing damage such as cracks even in extremely thin wafers or particularly brittle materials such as GaAs, until the cutting is completed.

Furthermore, a plurality of sliding members can be simultaneously fixed in appropriate forward and backward positions using one clamping means.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a cutting device for columnar material according to the present invention;
FIG. 2 is a diagram used to explain the cutting method using the cutting device for columnar material according to the present invention, and FIG. 3 is a plan view of a collection tray used in the cutting device for columnar material according to the present invention. Figures 4 and 5 are a sectional view taken along line A-A and line B-B in Figure 3, respectively, and Figure 6 is a cross-sectional view taken along line C-C in Figure 5.
7 is a cross-sectional view along the line, and FIG. 7 is a diagram used to show the vacuum tubes etc. connected to each vacuum chuck. FIGS. 8 and 9 are enlarged views of the vacuum chuck shown in FIG. 4, respectively. FIG. 10 is an enlarged view of the clamp device shown in FIG. 4, FIG. 11 is a sectional view taken along line D-D in FIG. 10, and FIG. 12 is another embodiment of the cutting device for columnar material according to the present invention. FIG. 13 is a schematic configuration diagram showing an example, and is a sectional view showing another embodiment of a collection tray applied to the cutting device for columnar material according to the present invention. 10... Column material (ingot), 12.63
...Inner peripheral blade, 30.72...Vacuum chuck, 31...Cylinder, 32...
Pad support ball, 34.76...Piston, 3
5.74...Suction pad, 50,...Clamp device, 51.71...Cylinder part, 52...
・First piston, 53...Second piston, 5
4...first ring, 55...second ring,
56... Clamp pin, 57... First plate, 58... Second plate. (~ around

Claims (4)

[Claims] (1) In a cutting device for columnar material that rotates a blade to cut a columnar material whose base end is fixed, the end face of the cutting side is held by suction by a suction holding means before cutting starts, and that state is maintained until the end of cutting. A cutting device for columnar material that cuts while maintaining the material. (2) The suction holding means includes a plurality of sliding members disposed to face the cut-side end surface of the fixed columnar material, and a plurality of sliding members arranged so as to face the cut-side end surface of the columnar material. a reduced pressure suction means that generates suction force so as to be held in contact with the tip of the sliding member; a cylinder portion and a piston disposed approximately in the center of the plurality of sliding members; a plurality of clamp pins arranged radially toward the sliding member; and a member that transmits a pressing force to the clamp pins as the piston moves in a direction in which the plurality of clamp pins press and fix the sliding member. and each sliding member is fixed in a state in which the tip of the plurality of sliding members follows the shape of the end face on the cut side of the columnar material and comes into contact with the end face. The apparatus for cutting columnar material according to claim 1. (3) The cutting device for columnar material according to claim 2, wherein the sliding member is a cylinder including a piston on which a suction pad is disposed via a spherical bearing. (4) The member that transmits the pressing force is disposed between a catch part formed on the piston or a member pressed by the piston and a catch part formed on the clamp pin, and 3. The apparatus for cutting columnar material according to claim 2, wherein the connecting member is a connecting member that tilts from an inclined position to a substantially horizontal position as the piston moves.