JP5368196B2 - Sheet peeling apparatus and peeling method - Google Patents

Description

  The present invention relates to a sheet peeling apparatus and a peeling method, and more particularly, to a sheet peeling apparatus and a peeling method that can peel an adhesive sheet against an adherend to prevent the adherend from being lifted.

  Recently, semiconductor wafers (hereinafter simply referred to as “wafers”) tend to require ultra-thin grinding while the wafer diameter increases. For this reason, in transporting a wafer that has been ground to an extremely thin thickness, the wafer is transported in a state of being warped by its own weight, so that there is a disadvantage that the wafer is broken. Here, in order to avoid such inconvenience, a wafer having a form disclosed in Patent Document 1 is used. In the same document, the concave portion is formed by grinding so that the thickness of the outer edge side of the wafer is relatively larger than the thickness of the other region, and the convex portion is formed along the outer edge of the wafer. It serves as a material to prevent the wafer from being damaged.

  When grinding a wafer as described above, a protective adhesive sheet is affixed to the circuit surface, and the adhesive sheet is peeled off from the wafer after a grinding process. Such an adhesive sheet peeling apparatus is disclosed in, for example, Patent Document 2. The apparatus includes plate-like pressing means that can press the adhesive sheet folded back during peeling to the wafer side, and is configured to peel while maintaining the folded posture of the adhesive sheet.

JP 2007-19379 A JP 2004-31535 A

  However, when the adhesive sheet is peeled off from the wafer as in Patent Document 1 in a state where the bottom surface of the recess is not supported by anything with the peeling device as in Patent Document 2, the bottom surface of the recess is a convex portion on the outer periphery. When the interval between the convex portions becomes a wide region because it is supported, the bottom of the concave portion is deformed so as to bend downward in the drawing by the elastic restoring force F of the adhesive sheet S as shown in FIG. This causes the inconvenience that cracks C will occur. By the way, if a table that can support the bottom surface of the recess is adopted, such inconvenience is eliminated, but the bottom surface of the recess is damaged by contacting the table, and the yield of the semiconductor chip is reduced. Inconvenience.

[Object of invention]
An object of the present invention is to provide a sheet peeling apparatus and a peeling method capable of peeling an adhesive sheet while preventing damage such as cracks from occurring on a wafer having convex portions formed along an outer edge.

To achieve the above object, the present invention provides a sheet peeling apparatus for peeling an adhesive sheet attached to one surface of a semiconductor wafer from the semiconductor wafer via a peeling tape.
The semiconductor wafer is provided with a convex portion formed along the outer edge by making the thickness of the outer edge side larger than the thickness of the other region, and a concave portion formed inside the convex portion on the other surface,
A table for supporting the semiconductor wafer from the other surface side in a state where a space is formed inside the convex portion by the concave portion, a feeding means for feeding the peeling tape to the one surface side, and a peeling tape. A sticking means for sticking to the adhesive sheet, a moving means for peeling the adhesive sheet by relatively moving the peeling tape and the semiconductor wafer, and a pressing means capable of pressing the adhesive sheet folded back during the peeling to the semiconductor wafer side. Prepared,
The pressing means is provided so as to be positioned on the folded edge of the adhesive sheet, and by separating and approaching the semiconductor wafer, the pressing force that presses the semiconductor wafer by the elastic restoring force of the adhesive sheet is peeled off. A configuration is adopted in which a pressing force control means is provided which can be adjusted according to the part and can prevent the concave portion of the semiconductor wafer from cracking .

Furthermore, the peeling method of the present invention is a sheet peeling method for peeling an adhesive sheet affixed to one surface of a semiconductor wafer from the semiconductor wafer via a peeling tape.
The semiconductor wafer is provided with a convex portion formed along the outer edge by making the thickness of the outer edge side larger than the thickness of the other region, and a concave portion formed inside the convex portion on the other surface,
Supporting the semiconductor wafer from the other surface side in a state where a space is formed inside the convex portion by the concave portion;
A step of feeding a peeling tape to the one surface side ;
Attaching the release tape to the adhesive sheet;
Pressing the folded edge of the adhesive sheet folded by moving the peeling tape and the adherend relative to the semiconductor wafer side with a pressing means ;
By adjusting the pressing means to be separated from and approaching the semiconductor wafer, the pressing force by which the semiconductor wafer is pressed by the elastic restoring force of the adhesive sheet is adjusted according to the peeling site, and the recess of the semiconductor wafer is broken. And a step of peeling the adhesive sheet from the semiconductor wafer while preventing it.

  According to the present invention, the pressing force applied to the wafer by the elastic restoring force of the adhesive sheet that is folded back by the pressing force control means can be controlled according to the peeled portion, so that even if the interval between the convex portions on the wafer becomes a wide region. As in the prior art, it is possible to prevent the wafer from being damaged by being deformed so that the concave bottom of the wafer is bent.

The schematic front view of the sheet peeling apparatus which concerns on embodiment. The principal part front view of an adhesive sheet peeling initial stage. The principal part front view in the adhesive sheet peeling. Explanatory drawing of a malfunction example.

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

  1 to 3, the sheet peeling apparatus 10 includes a table 11 that supports a semiconductor wafer W having an adhesive sheet S attached to one surface (upper surface in FIG. 1), and a belt-like shape for peeling the adhesive sheet S. The feeding means 12 for feeding the peeling tape PT, the cutting means 13 for cutting the peeling tape PT every predetermined length, and the peeling tape PT with the lead end side protruding outward from the outer periphery of the adhesive sheet S An attaching means 14 for attaching the tape PT to the adhesive sheet S, a holding means 15 comprising a chuck for holding the lead end side of the peeling tape PT, and a moving means for moving the holding means 15 in the left-right direction in FIG. A single-axis robot (not shown), a single-axis robot 16 constituting a moving means for moving the table 11 in the left-right direction in FIG. 1, and a pressing means 18 provided above the table 11. It is configured to include a. The peeling tape PT employs a heat-sensitive adhesive tape.

  The wafer W has a circular shape in plan view, and has a concave portion W1 having a circular shape in plan view formed by grinding the other surface (the lower surface in FIG. 1), and a convex portion W2 connected to the outer periphery of the concave portion W1. I have. Therefore, the convex portion W2 is formed in a circle along the outer edge of the wafer W by making the thickness of the outer edge side of the wafer W larger than the thickness of the other region, that is, the concave portion W1 formation region. Further, the wafer W is integrated with the ring frame RF from the surface side where the recess W1 is formed via the mounting sheet MS.

  A suction port (not shown) is provided on the upper surface of the table 11 so that the wafer W can be supported via the mounting sheet MS.

  The feeding means 12 is supported by the frame F and supports the peeling tape PT so that the peeling tape PT can be fed, a driving roller 22 that applies a feeding output to the peeling tape PT by driving the motor M, A pinch roller 23 sandwiching the peeling tape PT between the driving roller 22, a guide roller 24 positioned at the lower end of the frame F, a recess on the upper surface, and a shaft 25, a coil spring 26, and a bush 27. 1 and a tape guide plate 28 always urged to the left in FIG.

  The cutting means 13 includes a cutter blade 30, a cylinder 31 that moves the cutter blade 30 back and forth in the vertical direction, and a cylinder 32 that supports the cylinder 31 so as to be movable in the direction perpendicular to the paper surface in FIG.

  The affixing means 14 includes a heat block 35 and a cylinder 36 for moving the heat block 35 in the vertical direction, and adheres the peeling tape PT to the outer peripheral portion of the adhesive sheet S at the lower end of the heat block 35. It has become.

  The pressing means 18 includes a pressing roller 42 that is able to roll while being in contact with the adhesive surface of the adhesive sheet S, and a linear motor 43 as a pressing force control means that supports the pressing roller 42 so as to move up and down. It can be moved in the left-right direction in FIG. 1 via a single-axis robot (not shown). The pressing means 18 operates the linear motion motor 43 to lower the pressing roller 42, whereby the adhesive sheet S folded back during peeling can be pressed to the wafer W side, that is, downward in FIG. Further, the linear motor 43 controls the pressing force with which the wafer W is pressed by the elastic restoring force of the adhesive sheet S by moving the pressing roller 42 up and down during the peeling of the adhesive sheet S according to the progress of the peeling. It has a function. Specifically, as shown in FIGS. 2 and 3, the pressing roller 42 is positioned on the highest position SA of the folded edge of the adhesive sheet S having a semicircular arc shape, and the adhesive sheet S to be peeled is removed from the wafer. While urging to the W side, the pressing roller 42 is moved up and down according to the peeling site, that is, according to the progress of peeling. Further, the linear motor 43 has a function of previously storing a movement amount for controlling the pressing force and a function of moving the pressing roller 42 up and down according to the stored movement amount. The pressing roller 42 is coated with a fluororesin or a silicone resin so that the adhesive sheet S is not affixed even if it contacts the adhesive surface of the adhesive sheet S.

  Next, the sheet peeling method by the sheet peeling apparatus 10 in this embodiment is demonstrated.

  By the initial setting, as shown in FIG. 1, the lead end of the peeling tape PT is set so as to be positioned above the concave portion of the tape guide plate 28.

  An adhesive sheet S is attached to one surface, and a wafer W integrated with the ring frame RF via the mounting sheet MS from the other surface is placed at a predetermined position on the upper surface of the table 11 by a transfer device (not shown). Then, the holding means 15 moves to the right side in FIG. 1, moves the tape guide plate 28 to the right side to sandwich the lead end side of the peeling tape PT, and then moves to the left side to pull out the peeling tape PT. .

  Next, the heat block 35 is lowered and the peeling tape PT is pressed against the outer peripheral portion of the adhesive sheet S and pasted. Thereafter, the cutter blade 30 is lowered via the cylinders 31 and 32 and moved in the direction perpendicular to the paper surface in FIG. 1, whereby the peeling tape PT is cut above the concave portion of the tape guide plate 28.

  Next, as shown in FIG. 2, the holding means 15 is moved rightward in the figure by a single-axis robot (not shown), and the pressing roller 42 is also moved rightward in the figure to return the folding edge (maximum edge) of the adhesive sheet S. It is controlled to be positioned on position SA). Thereafter, the single-axis robot 16 and a single-axis robot (not shown) that moves the holding means 15 are operated at the same speed in the opposite direction (the arrow direction in FIG. 2), and the peeling tape PT attached to the adhesive sheet S; By moving the wafer W relative to the left and right, the adhesive sheet S is folded and peeled off from the wafer W. At this time, as shown in FIGS. 2 and 3, the pressing roller 42 is positioned on the highest position SA of the adhesive sheet S to be peeled, and applies a pressing force to the adhesive sheet S. Thereby, the adhesive sheet S can be peeled while pressing the wafer W downward, and the wafer W can be prevented from floating and cracking. Then, the peeling tape PT and the wafer W are further moved relative to each other to completely peel the adhesive sheet S from the wafer W. 2 and 3, since the table 11 is used as a reference, the presser means 18 is depicted as moving in the right direction in the figure. However, actually, the table 11 and the holding means 15 are separated from each other. Since it moves in the opposite direction at the same speed, the presser means 18 does not move in the left-right direction.

  Here, since the wafer W is supported only by the protrusions W2 formed along the outer edge, the interval between the protrusions W2 gradually increases as the separation progresses (after passing the center of the wafer W). Gradually narrowing). When the distance of the pressing roller 42 from the wafer W is kept constant with respect to such a wafer W, the wafer W can withstand the pressing force by the elastic restoring force of the adhesive sheet S as shown in the conventional example. It will not be cut and will crack. Therefore, the linear motion motor 43 moves the pressing roller 42 up and down according to the movement amount (peeling site) stored in advance. That is, the pressure roller 42 is moved upward so as to gradually move away from the wafer W by the linear motor 43 from the initial stage of peeling to the center of the wafer W, and from the center of the wafer W to the final stage of peeling. Is moved downward so as to gradually approach the wafer W. Thereby, even if a pressing force is applied to the wafer W by the elastic restoring force of the adhesive sheet S, the adhesive sheet S can be peeled without the wafer W being broken.

  Therefore, according to such an embodiment, during peeling of the adhesive sheet S, the pressing roller 42 is positioned at the highest position SA of the adhesive sheet S, and the adhesive sheet S is peeled while being pressed against the wafer W side. The wafer W is not pulled by the adhesive sheet S to be peeled and lifted upward to be broken. Moreover, the wafer W is pressed and cracked by the elastic restoring force of the adhesive sheet S at the position where the interval between the convex portions W2 is widened by the linear movement motor 43 moving the pressing roller 42 up and down in accordance with the separation site. Also disappear.

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.
Therefore, the description limited to the shape disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded one part or all part is included in this invention.

  For example, as long as it has the same functions and operations as those of the above-described embodiment, the single-axis robot 16 and the cylinders 31, 32, 36, and the linear motion motor 43 are other single-axis robots, linear motion motors, air cylinders, hydraulic cylinders, It may be replaced with the driving means.

Further, the relative movement between the peeling tape PT and the wafer W at the time of peeling the adhesive sheet S by the moving means may be performed by moving at least one of the table 11 and the holding means 15.
Further, the moving means may be operated so that the highest position SA of the adhesive sheet S is positioned below the pressing roller 42 without moving the pressing means 18 left and right in FIG.
Further, in addition to controlling the pressing force by moving the pressing roller 42 up and down in accordance with the movement amount stored in advance by the linear motion motor 43, the linear motion motor 43 can be used to detect torque so that the folding edge can be detected. by detecting the width of the elastic restoring force increases as the increase, but it may also be controlled so that the pressing force reaches a predetermined value.
Further, the peeling tape PT may be a pressure sensitive adhesive tape.
The semiconductor wafer may be a silicon wafer or a compound wafer.
Further, the feeding means 12 and the sticking means 14 may be configured by other than those shown in the above embodiment, and the sticking means 14 is attached to the adhesive sheet S as long as the feeding means 12 can feed the peeling tape PT. It is not limited at all as long as the peeling tape PT can be attached.

DESCRIPTION OF SYMBOLS 10 Sheet peeling apparatus 12 Feeding means 14 Sticking means 16 Single axis robot (moving means)
18 Pressing means 43 Linear motion motor (Pressing force control means)
PT peeling tape S adhesive sheet W semiconductor wafer W1 convex part

Claims (2)

In a sheet peeling apparatus for peeling an adhesive sheet attached to one surface of a semiconductor wafer from the semiconductor wafer via a peeling tape,
The semiconductor wafer is provided with a convex portion formed along the outer edge by making the thickness of the outer edge side larger than the thickness of the other region, and a concave portion formed inside the convex portion on the other surface,
A table for supporting the semiconductor wafer from the other surface side in a state where a space is formed inside the convex portion by the concave portion, a feeding means for feeding the peeling tape to the one surface side, and a peeling tape. A sticking means for sticking to the adhesive sheet, a moving means for peeling the adhesive sheet by relatively moving the peeling tape and the semiconductor wafer, and a pressing means capable of pressing the adhesive sheet folded back during the peeling to the semiconductor wafer side. Prepared,
The pressing means is provided so as to be positioned on the folded edge of the adhesive sheet, and by separating and approaching the semiconductor wafer, the pressing force that presses the semiconductor wafer by the elastic restoring force of the adhesive sheet is peeled off. A sheet peeling apparatus comprising a pressing force control means that can be adjusted according to a part and can prevent the concave portion of the semiconductor wafer from cracking . In the sheet peeling method of peeling the adhesive sheet affixed to one surface of the semiconductor wafer from the semiconductor wafer via the peeling tape,
The semiconductor wafer is provided with a convex portion formed along the outer edge by making the thickness of the outer edge side larger than the thickness of the other region, and a concave portion formed inside the convex portion on the other surface,
Supporting the semiconductor wafer from the other surface side in a state where a space is formed inside the convex portion by the concave portion;
A step of feeding a peeling tape to the one surface side ;
Attaching the release tape to the adhesive sheet;
Pressing the folded edge of the adhesive sheet folded by moving the peeling tape and the adherend relative to the semiconductor wafer side with a pressing means ;
By adjusting the pressing means to be separated from and approaching the semiconductor wafer, the pressing force by which the semiconductor wafer is pressed by the elastic restoring force of the adhesive sheet is adjusted according to the peeling site, and the recess of the semiconductor wafer is broken. And a step of peeling the adhesive sheet from the semiconductor wafer while preventing it.

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