JP2004128147A - Method and device for removing protection tape from semiconductor wafer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To securely and smoothly start peeling of a tape in a protection tape removing method from a semiconductor wafer for integrally peeling and removing the protection tape with a peeling tape from the semiconductor wafer by sticking the peeling tape on the protection tape of the semiconductor wafer where the protection tape is stuck on a whole face and peeling the peeling tape. <P>SOLUTION: Peeling of the tape is started from one end (e) of an orientation flat OF formed on an outer periphery of the semiconductor wafer W and a corner part formed by a notch. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for removing a protective tape existing on a surface of a semiconductor wafer (hereinafter, simply referred to as a “wafer”) using a peeling tape, and an apparatus used for the method.
[0002]
[Prior art]
For example, when polishing (back-grinding) the back surface of a wafer after pattern formation, a protective tape is applied in advance to the entire surface of the wafer, and the protective tape protruding from the outer periphery of the wafer is cut out along the outer periphery of the wafer. A polishing process is performed by sucking and holding a wafer entirely protected by a protective tape from the front side thereof with a suction cup. After that, the unnecessary protection tape is turned off from the wafer surface and removed.
[0003]
As a conventional method of removing and removing the protective tape from the wafer surface in this manner, a protective tape of a semiconductor wafer is pasted on a protective tape with a width smaller than the wafer diameter, and the protective tape is peeled off. 2. Description of the Related Art A method of integrally removing and removing a semiconductor wafer from a semiconductor wafer is known. In particular, the peeling start position of the protective tape is set at an arc portion of the outer shape of the wafer which is stable in shape, and the peeling tape is peeled from this portion.
[0004]
[Problems to be solved by the invention]
However, the above-described method of turning off the protective tape from the wafer surface has the following problems.
[0005]
That is, in the above-described peeling mode, since the tape peeling direction is orthogonal to the arc portion of the wafer outer shape, the peeling force is dispersed in the arc portion serving as the starting point of the peeling, and the protective tape is not successfully peeled from the wafer surface. There is a problem that a state occurs. In particular, in recent years, the curvature of the outer circular arc portion increases due to the increase in the diameter of the wafer, and the shape becomes closer to a straight line. Therefore, the dispersion of the peeling force further progresses, and the peeling tends to be more difficult.
[0006]
In addition, since the strength of the wafer is reduced by polishing the back surface of the wafer, a hard and strong protective tape is used to reinforce the wafer in a state where the protective tape is adhered. This makes it difficult to start peeling.
[0007]
The present invention has been made in view of such circumstances, and provides a protective tape removing method and a protective tape removing method capable of reliably and smoothly peeling and removing a protective tape on a wafer using a peeling tape. The main purpose is.
[0008]
[Means for Solving the Problems]
The present invention has the following configuration to achieve the above object.
[0009]
That is, the invention according to claim 1 is that the protective tape is attached to the protective tape on the semiconductor wafer to which the protective tape is attached, and the protective tape is separated from the semiconductor wafer by peeling off the release tape. In a method of removing a protective tape from a semiconductor wafer to be peeled and removed,
The peeling is started from a corner formed on the outer periphery of the semiconductor wafer.
[0010]
(Operation / Effect) When a peeling tape is applied on the protective tape attached to the semiconductor wafer and a peeling action is applied to the peeling tape, the peeling force at the start of the peeling is concentrated on the corners of the outer shape of the semiconductor wafer, and the large peeling stress As a result, the protective tape starts peeling off from the semiconductor wafer surface. Accordingly, the protective tape can be reliably and smoothly peeled even from a large-diameter semiconductor wafer having a large outer peripheral curvature.
[0011]
Further, even if the protective tape is hard and strong, the protective tape can be peeled off together with the peeling tape without difficulty.
[0012]
According to a second aspect of the present invention, in the method for removing a protective tape from a semiconductor wafer according to the first aspect, one end of an orientation flat formed on the outer periphery of the semiconductor wafer is set at the corner. The peeling is started from the part.
[0013]
(Function / Effect) The peeling force at the start of the peeling is concentrated at the corners where the arc portion of the semiconductor wafer outer shape and the linear portion forming the orientation flat intersect. Peeling starts from the wafer surface. Therefore, the method for removing a protective tape from a semiconductor wafer according to the first aspect can be suitably performed.
[0014]
According to a third aspect of the present invention, in the method for removing a protective tape from a semiconductor wafer according to the first aspect, a notch formed on an outer periphery of the semiconductor wafer is set at the corner, and peeling is performed from the corner. It is characterized by starting.
[0015]
(Operation / Effect) The peeling force at the start of peeling is concentrated on the notch formed by cutting out the outer shape of the semiconductor wafer, and the protective tape starts peeling from the surface of the semiconductor wafer starting from the notch due to a large peeling stress. Therefore, the method for removing a protective tape from a semiconductor wafer according to the first aspect can be suitably performed.
[0016]
The invention according to claim 4 is that the protective tape is adhered to the semiconductor wafer to which the protective tape is adhered, and the protective tape is peeled off the semiconductor wafer integrally with the peeling tape by peeling the peeling tape on the protective tape. In a protective tape removing device from a semiconductor wafer to be peeled and removed,
Position detecting means for detecting a corner formed on the outer periphery of the semiconductor wafer as a peeling start position of the protective tape,
A peeling table for placing and holding the semiconductor wafer at which the peeling start position of the protective tape is detected,
Release tape supply means for supplying a release tape on the protective tape of the semiconductor wafer held on the release table,
Tape attaching means for attaching the supplied peeling tape to a protective tape of a semiconductor wafer,
Tape peeling means for peeling the attached peeling tape from the corner of the semiconductor wafer,
A tape collecting unit for collecting a processed peeling tape peeled off together with the protective tape on the semiconductor wafer.
[0017]
(Operation / Effect) The corner formed on the outer periphery of the semiconductor wafer is detected, and the semiconductor wafer is placed and held on the peeling table such that the corner becomes the peeling start position of the protective tape. A release tape is attached on the surface of the semiconductor wafer placed and held, that is, on the protective tape, and the protective tape is peeled off from the corners integrally with the release tape. The peeled treated release tape is collected. Therefore, the method for removing a protective tape from a semiconductor wafer according to claim 1 can be suitably realized.
[0018]
According to a fifth aspect of the present invention, in the apparatus for removing a protective tape from a semiconductor wafer according to the fourth aspect, the peeling table is configured to be rotatable so that the mounted and held semiconductor wafer is at a predetermined angle. And a control means for adjusting a turning angle of the peeling table with respect to a peeling start portion of the semiconductor wafer.
[0019]
(Operation / Effect) Even if a semiconductor wafer is supplied in an arbitrary posture on the separation table, the rotation phase of the semiconductor wafer can be set by adjusting the rotation of the separation table itself, and the corner portion serving as the starting point of separation can be correctly positioned. Then, peeling can be started.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings, in which a protective tape attached to the surface of a semiconductor wafer (hereinafter simply referred to as a “wafer”) is peeled off after back grinding processing. .
[0021]
FIG. 1 is a perspective view showing an entire apparatus for removing a protective tape for a wafer according to the present invention, FIG. 2 is a front view thereof, FIG. 3 is a plan view thereof, and FIG. 4 is a front view of a tape attaching / peeling unit.
[0022]
The protective tape removing apparatus according to the present embodiment includes a wafer supply unit 1 in which a cassette C1 in which stacked wafers W on which back grinding processing is completed is loaded is loaded, and a wafer transfer mechanism 3 equipped with a bending and rotating robot arm 2. An alignment stage 4 for aligning the wafer W, a release tape supply unit 5 for supplying the release tape T to a release site, a release table 6 for holding the wafer W by suction, and a release tape for the wafer W on the release table 6 A tape adhering / peeling unit 7 for adhering and separating T, a tape collecting unit 8 for winding and collecting the separated peeled tape Ts, and a wafer loaded with a cassette C2 for stacking and storing the processed wafers W A W recovery unit 9 and a unit driving unit 10 for reciprocating the tape attaching / peeling unit 7 to the left and right are provided on an upper portion of the base 11. To have. Here, the wafer W supply unit 1, the wafer W transfer mechanism 3, the alignment stage 4, the peeling table 6, and the wafer W collection unit 9 are arranged in front of a vertical wall 12 erected on the upper surface of the base 11. At the same time, the tape applying / peeling unit 7 is provided at the lower opening of the vertical wall 12, and the unit driving unit 10 is provided at the back of the vertical wall 12.
[0023]
Hereinafter, each unit will be specifically described.
The wafer W supply unit 1 inserts and stores the wafer W in a horizontal posture with the protective tape affixed over the entire surface, facing upward, in a cassette C1 with an appropriate interval up and down. It is designed to be loaded on top.
[0024]
The cassette table 13 is turned by the expansion and contraction of the air cylinder 14 shown in FIG. The wafer recovery unit 9 also inserts and stores the wafer W after the protective tape peeling process in the cassette C2 with an appropriate interval up and down, and loads the wafer W on the cassette table 15. The cassette table 15 can also be turned by the expansion and contraction of the air cylinder 16 to change the direction.
[0025]
The robot arm 2 of the wafer transfer mechanism 3 is configured to be able to advance and retreat horizontally and to turn, and to take out the wafer W from the wafer supply unit 1, supply the wafer W to the alignment stage 4, and move the wafer from the alignment stage 4 to the separation table 6. , The unloading of the processed wafer W from the peeling table 6, and the loading of the processed wafer W into the wafer collecting unit 9.
[0026]
The alignment stage 4 aligns the placed wafer W based on an orientation flat or a notch. For example, when the alignment is performed based on the orientation flat, as shown in FIG. 9, when the wafer W is placed on the separation table 6, one end e of the orientation flat OF comes to the separation start position of the protective tape. Perform positioning in advance. Note that the alignment stage 4 corresponds to the position detecting means of the present invention.
[0027]
Returning to FIG. 1, the peeling tape supply unit 5 is configured to guide the peeling tape T derived from the raw roll TR to the tape attaching / peeling unit 7 through the upper part of the peeling table 6. It should be noted that the release tape T having a width smaller than the diameter of the wafer W is used.
[0028]
As shown in FIG. 4, at the center of the peeling table 6, a suction pad 17 having an upper surface configured as a vacuum suction surface is provided so as to be able to move up and down by an air cylinder 18, and the table upper surface is placed. The vacuum suction surface is configured to hold the wafer W without displacement. Further, the peeling table 6 is supported by a rotary actuator 19 so as to be pivotable at an arbitrary angle around a vertical axis X at the center of the table.
[0029]
The tape attaching / peeling unit 7 horizontally and horizontally feeds a movable table 22 supported slidably to the left and right along a pair of front and rear rails 21 by a feed screw shaft 24 driven forward and reverse by a motor 23. At the same time, the movable table 22 has a structure in which an edge member 25 for tape separation, a guide roller 26, a feed-out roller 27 driven and rotated, and a sandwiching roller 28 opposed thereto are provided. The tape applying / peeling unit 7 corresponds to the tape applying means and the tape removing means of the present invention.
[0030]
The tape application / separation unit 7 is controlled by a movement control means (not shown) so that the movement speed is reduced at both ends in the movement direction, that is, at the peripheral region of the wafer W.
[0031]
As shown in FIGS. 5 and 6, the edge member 25 of the tape attaching / peeling unit 7 is formed of a plate material having a sharp edge at the tip and wider than the wafer diameter. It is connected and fixed to a rotating support shaft 29 movably protruded and supported so as to be adjustable in the front-rear position.
[0032]
An operating arm 30 is fastened and connected to the base of the rotary support shaft 29, and a connecting rod pivotally connected to the free end of the operating arm 30 is connected to a piston of an air cylinder 31 mounted on the front surface of the movable base 22. It is connected to the rod 31a. The rotation support shaft 29 is rotated by the swing of the operation arm 30 accompanying the advance / retreat operation of the piston rod 31a, whereby the distal end portion of the edge member 25 is configured to move up and down.
[0033]
The connecting rod 32 extending upward from the free end of the operating arm 30 is screwed and connected to the piston rod 31a of the air cylinder 31, and by adjusting the screwing amount of the connecting rod 32, the piston rod 31a is adjusted. The swing angle of the operation arm 30 when the protruding operation reaches the stroke end, in other words, the angle of the edge member 25 at the lower limit position can be arbitrarily adjusted.
[0034]
Next, a round operation of peeling off the protective tape stuck on the surface of the wafer W using the apparatus of the above embodiment will be described with reference to FIGS. 6, 7 (a) to 7 (c), FIGS. 8 (e), (f), and FIGS. This will be described with reference to FIG.
[0035]
First, the robot arm 2 sucks and holds one wafer W from the cassette C1 of the wafer supply unit 1, takes out the wafer W, and transfers it onto the alignment stage 4. Here, based on the detection of the orientation flat OF (or notch) of the wafer W, Thus, the alignment of the wafer W is performed. The aligned wafer W is transported again by being supported by the robot arm 2 and supplied onto the peeling table 6.
[0036]
After the wafer W carried into the separation table 6 is received by the suction pad 17 protruding above the table, the wafer W is mounted on the upper surface of the separation table 6 in a predetermined posture and position as the suction pad 17 descends. Then, the surface to which the protective tape P is stuck is held by suction in an upward posture.
[0037]
Next, the peeling table 6 is turned at a predetermined angle determined based on the alignment information on the alignment stage 4 so that one end e of the orientation flat OF formed on the outer periphery of the wafer W is true in the longitudinal direction of the peeling tape. The phase adjustment is performed toward the rear (right side in FIG. 6). At this time, as shown in FIG. 7A, the tape applying / peeling unit 7 is at a standby position away from the peeling table 6 rearward.
[0038]
When the phase adjustment of the wafer W loaded on the peeling table 6 is completed, the tape applying / peeling unit 7 moves forward onto the wafer W as shown in FIG. The edge of the edge member 25 is moved to a point a short distance from the peripheral edge of the wafer W on the standby position side, and at this point, the air cylinder 31 is protruded to the stroke end, and the operation of the operating arm 30 causes the edge to move. The member 25 is lowered to the lower limit position. That is, the tip of the edge member 25 contacts the surface of the release tape T, and presses the release tape T against the surface of the protective tape P.
[0039]
When the edge member 25 descends, as shown in FIG. 7C, the tape applying / peeling unit 7 moves backward in the standby position direction. In other words, the release tape T is attached to the surface of the protective tape P while pressing the release tape T with the tip of the edge member 25. At this time, the moving speed of the tape applying / peeling unit 7 is set so as to become slower toward the periphery of the wafer W in the process of applying the peeling tape.
[0040]
When the leading end of the edge member 25 reaches the peripheral end of the wafer W, as shown in FIG. 8D, the tape applying / peeling unit 7 reverses its moving direction and moves forward. At this time, the distal end of the edge member 25 is moved while pressing the release tape T against the surface of the protective tape P, and the feed roller 27 winds up the release tape T at a peripheral speed synchronized with the moving speed. . That is, by peeling off the peeling tape T, the protective tape P adhered and supported by the peeling tape T and integrated therewith is peeled off from the wafer surface.
[0041]
When the peeling tape T is peeled off, as shown in FIG. 9, a corner formed at one end e of the orientation flat OF located at the forefront in the tape peeling direction is a starting point of peeling, and a small area of this corner is obtained. When the peeling stress is concentrated on the site, the peeling is started reliably and smoothly.
[0042]
The feed roller 27 is rotationally driven by a drive device (not shown) via a slip clutch that idles with a load equal to or more than a predetermined torque, and is configured to always feed the peeling tape T while applying a predetermined tension.
[0043]
As shown in FIG. 8 (e), when the tape attaching / peeling unit 7 passes over the wafer W and the protective tape P is completely peeled off from the surface of the wafer W, the wafer W is placed on the peeling table 6 by the robot arm 2. And is inserted and stored in the cassette C2 of the wafer collecting section 9. After that, the tape applying / peeling unit 7 is moved back to the original standby position and moved back, and the peeled and processed peeled tape Ts is wound up and collected. The edge member 25 is also returned to the original standby position.
[0044]
As described above, one protection tape peeling process is completed, and the next wafer receiving standby state is set.
[0045]
In the present embodiment, the peeling table 6 is turned at a predetermined angle determined based on the alignment information determined by the alignment stage 6, and the position of the corner of the wafer W, which is the peeling start position of the protective tape P, is started. The alignment is adjusted, and the peeling tape T is stuck on the wafer W, that is, on the protective tape P, and peeled off from the corner of the wafer W in a state where the two tapes are integrated. Therefore, since the peeling stress at the time of peeling the protective tape P is concentrated on the corners, the protective tape P can be peeled off the wafer W reliably and smoothly.
[0046]
The present invention is not limited to the above embodiment, but may be modified as follows.
(1) As shown in FIG. 10, in a wafer W having a notch N for positioning formed on the periphery, the notch (an example of a corner) N is placed on the peeling table 6 such that the notch N is a starting point of tape peeling. The phase of the wafer W may be adjusted. Also in this case, the peeling stress at the peeling start part concentrates on the notch part, and the peeling can be started without difficulty.
[0047]
(2) The means for loading the wafer W onto the separation table 6 with the corners formed in the peripheral portion of the wafer such as the orientation flat 0F and the notch N positioned at a predetermined separation start point is as described above. The position of the corner portion of the wafer W loaded on the separation table 6 is detected by a CCD camera or other sensors without being limited to the form in which the rotation of the separation table 6 is controlled based on the alignment information on the stage 4. The rotation of the peeling table 6 may be controlled based on the image information and the detection information.
[0048]
(3) As means for rotating the peeling table 6, in addition to using the rotary actuator 19 as described above, a rotary drive mechanism using an electric motor or an air cylinder may be appropriately selected.
[0049]
(4) The present invention can also be used for removing a protective tape from a wafer (wafer mounted on a mount frame) adhered to and supported on a ring frame via an adhesive tape.
[0050]
(5) In the above-described embodiment, the single unit 7 performs the attachment and the detachment of the release tape T. However, the tape attachment unit that performs only the attachment and the tape separation unit that performs only the detachment can be moved forward and backward separately. It can also be deployed and implemented.
[0051]
【The invention's effect】
As is clear from the above description, according to the present invention, the peeling stress is concentrated on the corner formed on the outer periphery of the semiconductor wafer, and the peeling is started from the corner, so that the curvature of the outer periphery is large. Even with a large-diameter wafer, the protective tape can be reliably and smoothly peeled off and removed integrally with the peeling tape. In addition, even a hard and strong protective tape can be peeled off with a release tape without difficulty and stably.
[Brief description of the drawings]
FIG. 1 is a perspective view showing the overall configuration of a protective tape removing device.
FIG. 2 is an overall front view of the protective tape removing device.
FIG. 3 is an overall plan view of the protective tape removing device.
FIG. 4 is a front view of a tape attaching / peeling unit and a peeling table.
FIG. 5 is a partially longitudinal front view showing a support structure of an edge member for tape application / peeling.
FIG. 6 is a perspective view of a main part showing a tape attaching / peeling state.
FIGS. 7A to 7C are front views illustrating a tape attaching / peeling process.
FIGS. 8D and 8E are front views illustrating a tape attaching / peeling process.
FIG. 9 is a plan view showing a positioning state of a wafer with an orientation flat on a peeling table.
FIG. 10 is a plan view showing a positioning state of a notched wafer on a peeling table.
[Explanation of symbols]
6 Peeling table 8 Tape collecting part P Protective tape T Peeling tape W Semiconductor wafer OF Orientation flat N Notch

Claims (5)

A protective tape is adhered on the protective tape of the semiconductor wafer to which the protective tape is attached, and the protective tape is peeled off from the semiconductor wafer integrally with the release tape by peeling off the release tape. In the method,
A method for removing a protective tape from a semiconductor wafer, wherein peeling is started from a corner formed on an outer periphery of the semiconductor wafer. A method for removing a protective tape from a semiconductor wafer according to claim 1,
A method for removing a protective tape from a semiconductor wafer, comprising setting one end of an orientation flat formed on the outer periphery of the semiconductor wafer to the corner and starting peeling from the corner. A method for removing a protective tape from a semiconductor wafer according to claim 1,
A method for removing a protective tape from a semiconductor wafer, comprising: setting a notch formed on the outer periphery of the semiconductor wafer at the corner; and starting peeling from the corner. A protective tape is adhered on the protective tape of the semiconductor wafer to which the protective tape is adhered, and the protective tape is peeled off from the semiconductor wafer integrally with the release tape by peeling off the protective tape. In the device,
Position detecting means for detecting a corner formed on the outer periphery of the semiconductor wafer as a peeling start position of the protective tape,
A peeling table for placing and holding the semiconductor wafer at which the peeling start position of the protective tape is detected,
Release tape supply means for supplying a release tape on the protective tape of the semiconductor wafer held on the release table,
Tape applying means for applying the supplied peeling tape on the protective tape of the semiconductor wafer,
Tape peeling means for peeling the attached peeling tape from the corner of the semiconductor wafer,
An apparatus for removing a protective tape from a semiconductor wafer, comprising: a tape collecting unit for collecting a processed peeling tape peeled off together with the protective tape on the semiconductor wafer. An apparatus for removing a protective tape from a semiconductor wafer according to claim 4,
The peeling table is configured to be rotatable so as to make the semiconductor wafer placed and held at a predetermined angle, and is provided with control means for adjusting a rotating angle of the peeling table with respect to a peeling start portion of the semiconductor wafer. Characteristic device for removing protective tape from semiconductor wafers.

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