JP2007296590A - Sheet cutting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cut a sheet in response to the size of a plate-like member in a state of sticking to the plate-like member a sheet of the size projecting from the outer periphery of the plate-like member such as a wafer. <P>SOLUTION: This sheet cutting method cuts the sheet S of the size projecting from the outer periphery of a semiconductor wafer W by a cutter blade 12 along the outer periphery of the semiconductor wafer W. This cutting method presets a moving locus of a blade 12B as a normal locus so that the sheet S does not project from the semiconductor wafer W, and adjusts an attitude of the cutter blade 12 so as to become a predetermined twin angle α1, a camber angle α2 and a caster angle α3, in a process of being approached to the normal locus, after inserting the blade 12B of the cutter blade 12 into a cutting starting position P separated from the normal locus in cutting. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sheet cutting method, and more specifically, a sheet that can be cut in accordance with the shape of a plate-like member after a sheet having a size protruding from the outer periphery of the plate-like member is attached to the plate-like member. It relates to a cutting method.

  2. Description of the Related Art Conventionally, a protective sheet for protecting a circuit surface serving as a surface of a semiconductor wafer (hereinafter simply referred to as “wafer”) has been applied.

  Cutting when applying such a protective sheet is performed by attaching a protective sheet of a size that protrudes from the outer periphery of the wafer to the wafer, and then moving the cutter blade along the outer periphery of the wafer so that the protective sheet is shaped into the shape of the wafer. (See, for example, Patent Document 1).

Japanese Patent No. 2919938

However, in the sheet cutting method disclosed in Patent Document 1, it is only necessary to adjust the insertion depth of the cutter blade, and there are various methods by which a mechanism for changing the posture, such as angle adjustment of the cutter blade, is not provided. Cause inconvenience.
That is, as shown in FIG. 7A, the blade 50A of the cutter blade 50 is inserted substantially perpendicularly to the surface of the sheet S attached to the wafer W on the table T and cut along the outer periphery of the wafer W. And when the back surface grinding is performed after the cutting, there is an inconvenience that a protruding portion L of the sheet S is generated as shown in FIG. That is, because the wafer W is chamfered so that the outer peripheral end swells outward, the diameter is inevitably reduced by grinding, and the difference is generated as the protruding portion L.

  Therefore, in order to prevent the protruding portion L from being generated, the cutter blade 50 is displaced in an inclined posture with respect to the surface of the sheet S as shown in FIG. You just have to do it. However, in such a method, when the blade 50A is inserted, there is a disadvantage that the blade tip is easily broken due to the influence of the thickness, rigidity, etc. of the sheet S as shown in FIG. To do.

  Further, as shown in FIG. 9, when a method of inclining the cutter blade 50 after inserting the blade 50A into the sheet S in a vertical posture is adopted, the sheet S on the wafer W according to the displacement amount. This causes inconvenience that wrinkles are generated and, in some cases, the wafer W is broken.

[Object of invention]
The present invention has been devised by paying attention to such inconveniences, and its purpose is to cut a sheet affixed to a plate-like member such as a wafer in accordance with the shape of the plate-like member. It is an object of the present invention to provide a sheet cutting method capable of preventing wrinkles and cracking of the wafer and preventing the sheet from protruding from the outer periphery of the wafer.

In order to achieve the above-mentioned object, the present invention cuts the sheet according to the shape of the plate-like member via a cutter blade after sticking a sheet of a size protruding from the outer periphery of the plate-like member to the plate-like member. In the sheet cutting method,
A trajectory for cutting the sheet according to the shape of the plate-like member by relatively moving the cutter blade along the outer periphery of the plate-like member is a normal locus,
A first step of inserting a cutter blade into the sheet with a position away from the normal locus as a cutting start position;
A second step of cutting the sheet by relatively moving the cutter blade so as to gradually approach the regular trajectory while the cutter blade is inserted into the sheet;
And a third step of cutting the sheet in accordance with the shape of the wafer by relatively moving the cutter blade in a state where the cutter blade is positioned on a normal locus.

  In the present invention, while the cutter blade moves on the regular locus from the cutting start position, the cutter blade has a predetermined toe-in angle at which a center line of the cutter blade is inclined with respect to the cutting direction in a top view of the cutting direction. It is preferable that the sheet is cut in a state where the posture is displaced so that the edge of the cutter blade is closer to the outer periphery of the plate-like member than the back portion on the normal locus.

  Further, while the cutter blade moves on the regular locus from the cutting start position, the cutter blade has a predetermined camber angle in which the center line of the cutter blade is inclined with respect to the cutting direction in a front view of the cutting direction. It is also possible to adopt a method in which the sheet is cut without protruding from the outer periphery of the plate member by moving the cutter blade on the normal trajectory while maintaining the camber angle while maintaining the camber angle.

  Further, while the cutter blade moves on the regular locus from the cutting start position, the cutter blade has a predetermined caster angle at which the center line of the cutter blade is inclined with respect to the cutting direction in a side view of the cutting direction. And the cutter blade moves on the normal trajectory while the angle formed between the sheet and the blade edge is maintained at an acute angle, so that the sheet can be cut.

  Further, it is preferable to adopt a method in which the cutter blade is supported by a numerically controlled articulated robot and controlled in posture.

According to the present invention, the cutter blade can be gradually changed in the process of inserting the cutter blade at a position away from the normal locus and bringing the cutter blade closer to the normal locus. The sheet can be cut in accordance with the shape of the wafer W without generating wrinkles on the sheet near the trajectory or applying an unreasonable load to the outer periphery of the wafer W.
In addition, the cutter blade posture can be adjusted so that the toe-in angle, camber angle, and caster angle at the time of cutting can be adjusted from the cutting start position away from the wafer outer periphery to the normal movement of the cutter blade. Therefore, there is no risk of wrinkles on the sheet or cracking of the wafer depending on the posture of the cutter blade located on the normal locus, and the sheet is cut under optimum conditions according to the thickness, rigidity, etc. of the sheet Is possible.
Furthermore, by cutting with a cutter blade supported by an articulated robot that is numerically controlled, it is possible to perform sheet cutting with a complicated planar shape by adding diversity to the movement trajectory of the cutter blade.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a sheet cutting apparatus 10 according to the present embodiment, and a wafer W as a plate-like member that is provided in the sheet cutting apparatus 10 and has a substantially circular planar shape, and supports the wafer substantially horizontally. The schematic front view of the table T which affixes the protective adhesive sheet S on the upper surface (circuit surface) of W is shown. In this figure, the sheet cutting apparatus 10 is configured to include an articulated robot 11 and a cutter blade 12 held by the robot 11.

  The robot 11 includes a base portion 14, first arm 15 </ b> A to sixth arm 15 </ b> F disposed on the upper surface side of the base portion 14 and provided to be rotatable in the directions of arrows A to F, and the tip of the sixth arm 15 </ b> F. And a tool holding chuck 19 attached to the free end side of the robot 11. The second, third, and fifth arms 15B, 15C, and 15E are rotatably provided in the Y × Z plane in FIG. 1, and the first, fourth, and sixth arms 15A, 15D, and 15F are It is provided so as to be rotatable around its axis. The robot 11 in this embodiment is controlled by numerical control. That is, the amount of movement of each joint relative to the workpiece (wafer W) is controlled by numerical information corresponding to each, and the amount of movement is all controlled by a program, and the wafer size is the same as in a conventional cutting apparatus. The method uses a completely different method from the method in which the position of the cutter blade is manually changed every time the change is made. Further, in the conventional cutting apparatus, it has been necessary to readjust the cutting diameter each time in accordance with the change in the posture of the cutter blade (toe angle α1, camber angle α2, caster angle α3, which will be described later). No. 11 can maintain the cutting diameter at a set value with high accuracy, no matter how the posture of the cutter blade is changed.

  As shown in FIG. 2, the tool holding chuck 19 is arranged at a position spaced apart from the cutter blade receiver 20 having a substantially cylindrical shape by an interval of about 120 degrees in the circumferential direction of the cutter blade receiver 20. And three chuck claws 21 that detachably hold 12. Each chuck claw 21 is formed as a pointed portion 21A having an acute inward end, and can be advanced and retracted in the radial direction with respect to the center of the cutter blade receiver 20 by air pressure.

  As shown in FIG. 3, the cutter blade 12 includes a blade holder 12A that forms a base region, and a blade 12B that is detachably fixed to the distal end side of the blade holder 12A. The blade holder 12A has a substantially cylindrical shape, and grooves 22 are formed along the axial direction on the base end side of the outer peripheral surface at positions spaced at an interval of about 120 degrees in the circumferential direction. By engaging the portion 21A, the position of the cutter blade 12 with respect to the tool holding chuck 19 is kept constant.

  The blade 12B includes a base portion 12C supported by the blade holder 12A, a back portion 12D along the axis of the blade holder 12A, and a blade edge 12F oriented in an acute angle direction from the tip portion 12E of the back portion 12D. Accordingly, the blade edge 12F has a width on the tip 12E side smaller than a width on the base 12C side.

As shown in FIG. 1, the table T includes an outer table 41 having a substantially square shape in plan view and an inner table 42 having a substantially circular shape in plan view. The outer table 41 is provided in a concave shape capable of receiving the inner table 42 in a state where a gap is formed between the outer table 41 and the outer edge of the inner table 42, and can be moved up and down with respect to the base 45 via the single-axis robot 44. Is provided. On the other hand, the inner table 42 is provided so as to be movable up and down with respect to the outer table 41 via a single-axis robot 46. Therefore, the outer table 41 and the inner table 42 can be moved up and down integrally, and can be moved up and down independently of each other, whereby a predetermined height position is set according to the thickness of the sheet S and the thickness of the wafer W. Can be adjusted.

  A sheet feeding unit (not shown) for feeding the sheet S onto the wafer W is arranged on the upper side of the table T. The sheet S fed from the sheet feeding unit onto the wafer W is not shown. The bonding roller moves in the sheet feeding direction while rotating on the sheet S, whereby the sheet S is bonded to the upper surface of the wafer W.

  Next, a method for cutting the sheet S in the present embodiment will be described with reference to FIGS. The sheet S is affixed to the wafer W in the manner disclosed in Japanese Patent Application No. 2005-198806.

  As an initial setting, as shown in FIG. 4, a toe-in angle α1 in which the center line of the cutter blade 12 is inclined with respect to the cutting direction along the outer periphery of the wafer W in the top view of the cutting direction, as shown in FIG. The camber angle α2 in which the center line of the cutter blade 12 is inclined when viewed in the front direction, and the caster angle α3 in which the center line of the cutter blade 12 is inclined in the cutting direction in the side view of the cutting direction as shown in FIG. Is done. The reason for setting such toe-in angle α1, camber angle α2, and caster angle α3 is to enable cutting under optimum conditions according to the thickness, rigidity, etc. of sheet S.

  Further, when the blade 12B cuts the sheet S while maintaining the angles α1, α2, and α3, a movement locus for cutting the sheet S without protruding in accordance with the shape of the wafer W is a normal locus. Is input. This normal locus can be determined by the diameter of the wafer W. Further, a predetermined position (refer to a two-dot chain line position in FIG. 4) that is away from the normal locus is input as the cutting start position P.

  Next, the wafer W is placed on the table T, and the sheet S is attached to the upper surface side of the wafer W. At the time of sticking, the cutter blade 12 held by the robot 11 stands by at a predetermined position so as not to interfere with the sheet S in position.

  When the application of the sheet S is completed, the blade 12B moves to the cutting start position P via the robot 11, and the blade 12B has a predetermined depth on the surface of the sheet S in a posture in which the axis of the blade holder 12A is substantially vertical. Plugged in.

  In the state where the blade 12B is inserted into the surface of the sheet S in this way, the cutter blade 12 approaches the normal locus along a substantially arcuate locus as viewed from above, as indicated by a dotted line in FIG. While cutting the sheet S, the posture is gradually displaced so that the set toe-in angle α1, camber angle α2, and caster angle α3, and the edge 12F is substantially in contact with the outer periphery of the wafer W, that is, on the normal locus. When moved (see the solid line position in FIG. 4), the angles α1 to α3 become set angles.

  While maintaining these angles, the blade 12B moves on the normal trajectory via the robot 11 and cuts the sheet S in accordance with the shape of the wafer W by rotating substantially one turn.

  After the cutting of the sheet S is completed, the cutter blade 12 returns to a predetermined standby position, while the wafer W is transferred by a transfer device (not shown), and the unnecessary unnecessary sheet portion generated by the cutting is not shown. The next wafer W is transferred onto the table T after being wound by the winding device, and thereafter the cutting operation is performed in the same manner.

  Therefore, according to such an embodiment, the posture of the blade 12B of the cutter blade 12 is configured to move on a normal trajectory in contact with the outer periphery of the wafer W while being gradually displaced. Alternatively, it is possible to effectively avoid the inconvenience of breaking the outer peripheral portion of the wafer W, and even when the back surface of the wafer W is ground, the inconvenience that the sheet S protrudes from the outer periphery of the wafer W. The effect that it can be eliminated is obtained.

As described above, the best configuration, method and the like for carrying out the present invention have been disclosed in the above description, but the present invention is not limited to this.
In other words, the present invention has been illustrated and described mainly with respect to specific embodiments, but without departing from the scope of the technical idea and object of the present invention, the shape, position, or With respect to the arrangement and the like, those skilled in the art can make various changes as necessary.

  For example, in the above-described embodiment, the semiconductor wafer is illustrated and described as the plate-like member, but the present invention is not limited to this, and other plate-like members such as glass, steel plate, or resin plate are also targeted. The semiconductor wafer may be a silicon wafer or a compound wafer. Further, the planar shape of the plate-like member is not limited to a substantially circular shape, and may be various planar shapes such as an ellipse and a polygon.

1 is a schematic front view of a sheet cutting device and a table according to the present embodiment. The expansion perspective view which shows the front end side area | region of a robot. The expansion perspective view of a cutter blade. Operation | movement explanatory drawing which cut | disconnects a sheet | seat, keeping a toe-in angle. Explanatory drawing of operation | movement which cut | disconnects a sheet | seat maintaining a camber angle | corner. Operation | movement explanatory drawing which cut | disconnects a sheet | seat, maintaining a caster angle. (A) is sectional drawing which shows the prior art example which cut | disconnects a sheet | seat along a wafer outer periphery, (B) is a partial expanded sectional view which shows the state which produces a protrusion part by wafer back surface grinding after cut | disconnecting a sheet | seat. (A) is sectional drawing which shows the state which inserts a blade in a sheet | seat, maintaining a camber angle, (B) is a cross section for demonstrating the case where a blade is damaged when inserting a blade in a sheet | seat in the state which maintained the camber angle. Figure. Sectional drawing for demonstrating the inconvenience at the time of attitude | position displacement so that it may have a camber angle from the state which inserted the blade in the sheet | seat.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Sheet cutting device 11 Robot 12 Cutter blade 12B Blade 12D Back part 12F Blade edge P Cutting start position S Sheet W Semiconductor wafer (plate-shaped member)
α1 Toe-in angle α2 Camber angle α3 Caster angle

Claims (5)

In the sheet cutting method of cutting the sheet according to the shape of the plate member through a cutter blade after pasting the sheet of a size protruding from the outer periphery of the plate member to the plate member,
A trajectory for cutting the sheet according to the shape of the plate-like member by relatively moving the cutter blade along the outer periphery of the plate-like member is a normal locus,
A first step of inserting a cutter blade into the sheet with a position away from the normal locus as a cutting start position;
A second step of cutting the sheet by relatively moving the cutter blade so as to gradually approach the regular trajectory while the cutter blade is inserted into the sheet;
A sheet cutting method comprising: a third step of cutting the sheet in accordance with the shape of the wafer by relatively moving the cutter blade in a state where the cutter blade is positioned on a normal locus. While the cutter blade moves on the normal locus from the cutting start position, the cutter blade is positioned so that the center line of the cutter blade has a predetermined toe angle that is inclined with respect to the cutting direction when viewed from above in the cutting direction. The sheet cutting method according to claim 1, wherein the sheet is cut in a state where the sheet edge is displaced and the edge of the cutter blade is closer to the outer periphery of the plate-like member than the back portion on the normal locus. While the cutter blade moves on the regular locus from the cutting start position, the cutter blade is positioned so that the center line of the cutter blade has a predetermined camber angle that is inclined with respect to the cutting direction when viewed in the cutting direction. 3. The sheet according to claim 1, wherein the sheet is cut without protruding from an outer periphery of the plate-like member by moving the cutter blade on the normal locus while maintaining the camber angle. 4. Cutting method. While the cutter blade moves on the regular locus from the cutting start position, the cutter blade is positioned so that the center line of the cutter blade has a predetermined caster angle inclined with respect to the cutting direction in a side view of the cutting direction. 4. The sheet according to claim 1, wherein the sheet is cut by moving the cutter blade on the normal trajectory in a state where the sheet is displaced and the angle formed by the sheet and the blade edge is maintained at an acute angle. Sheet cutting method. The sheet cutting method according to any one of claims 1 to 4, wherein the cutter blade is supported by a numerically controlled articulated robot and controlled in posture.

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