CN1260779C - Method and device for removing useless materials from semiconductor wafers - Google Patents

Abstract

According to the present invention, an apparatus for removing useless substances from a semiconductor wafer supplies a peeling tape T to a protective tape P on the surface of a semiconductor wafer W. As shown in FIG. An edge member 28 is arranged to be in contact with the surface of the release tape T and to move along the protective tape P. As shown in FIG. The peeling tape T is peeled off when it is folded back at a large angle of 90 degrees or more at the end of the edge piece 28 . The protective tape P is peeled and removed from the wafer surface along with the peeling tape T. As a result, useless substances are removed with high precision without damaging the wafer W.

Description

Method and apparatus for removing unwanted substances from semiconductor wafers

technical field

The present invention relates to a method of removing useless substances, such as a protective tape, a protective layer, etc., from the surface of a semiconductor wafer (abbreviated as wafer hereinafter) using a peeling tape and an apparatus using the method.

Background technique

Generally, when the backside of the wafer is ground after the pattern forming process (back grinding), at first a wide protective band is provided on the surface of the wafer, a part of the protective band protruding from the outer periphery of the wafer is cut off along the wafer periphery, and then the wafer is The grinding process is performed while its entire surface is protected by a protective tape, and is supported on the surface by suction through a suction cup. Then, the protective tape, which is now a useless substance, is peeled off and removed from the surface of the wafer.

The removal method using the stripping tape comes in the form of a device for peeling off the protective tape, the appearance of which is shown in Figure 30. In this removal method, a peeling tape T having a stronger adhesiveness than the protective tape P is supplied to the protective tape (useless substance) P bonded to the surface of the wafer W. The peeling tape T is rolled up while the peeling roller 40 rolls on the wafer and moves to the right in FIG.

In this way, the peeling tape T is wound up following the curvature of the peeling roller 40 . At a point where the protective tape P is peeled from the surface of the wafer W, the peeling angle of the protective tape P with respect to the wafer surface is small, close to zero, and the peeling force is applied in a direction almost perpendicular to the wafer W. As a result, where the wafer W is weak, as shown in FIG. 31, the wafer may break at the point A.

Furthermore, as shown in FIG. 32, a wafer W having a bevel b formed by obliquely cutting the outer periphery may be background to a large extent to a level G of the bevel b. With such a thin wafer W, as shown in FIG. 33, the protruding end Pa of the protective tape P may drop and stick to the bevel b. In this case, it may be difficult to start peeling off the protective tape P at the end. When the peeling tape T is wound up with the peeling roller 40 rolling in this state, the wafer W is easily broken.

The above phenomenon that the wafer is broken by the tape peeling force applied when the peeling tape is peeled also occurs when the peeling tape is directly supplied to the surface of the wafer to remove the protective layer (useless substances) remaining on the wafer surface with the peeling tape.

Contents of the invention

The present invention has considered the above-mentioned state of the art, and an object thereof is to provide a cleaning method and apparatus for peeling and removing useless substances from a wafer by using a stripping tape, while avoiding cracking of the wafer due to the stripping force of the tape.

In order to achieve the above objects, the present invention provides a method for removing useless substances from the semiconductor wafer by providing a stripping tape to the semiconductor wafer, and stripping the useless substances together with the stripping tape from the semiconductor wafer, the method comprising the steps of: An edge member is arranged to contact the surface of the release tape provided to the semiconductor wafer and peels off the release tape while being folded back at a peeling angle provided by the end of the edge member, and when the end of the edge member moves beyond the When an end of the semiconductor wafer is attached, the end of the edge member is prevented from falling.

In the above method, the release tape provided to the wafer is folded back at the release corner provided at the end of the edge piece. Thus, the tape peel angle relative to the wafer surface is greater than the peel angle using peel rolls. Therefore, the peeling tape can be peeled without applying a strong peeling force to the wafer. Unwanted substances can be peeled off and removed from the surface of even thin wafers together with the stripping tape without damaging the wafers.

In the method for removing unwanted substances according to the present invention, the peeling angle provided to the peeling tape by the end of the edge member is preferably an acute angle or an obtuse angle. More preferably, the obtuse angle is at least 90 degrees and the acute angle is less than 90 degrees.

That is, the height of the end of the edge piece remains constant. The end of the edge piece remains at a constant height from the beginning to the end of the movement.

In the method of removing unwanted substances according to the present invention, the tip of the edge member is preferably reciprocated at the end of the wafer by a small stroke.

The peel tape can be efficiently peeled and removed from the wafer by reciprocating the edge member to peel off the tape and reach the end of the wafer.

In the method for removing unwanted substances according to the present invention, the unwanted substances on the semiconductor wafer are preferably a protective tape applied to the surface of the wafer or a protective layer formed on the surface of the wafer.

The present invention also provides a device for removing useless substances from a semiconductor wafer, the device comprising: a stripping table supporting the semiconductor wafer; a tape server providing a stripping tape for the semiconductor wafer on the stripping table; receiving the stripping tape and providing The tape application unit of this peeling belt semiconductor wafer; One has edge piece, so that peel off the tape stripping unit of peeling tape from semiconductor wafer, it starts from the end of semiconductor wafer, is provided by the opposite peeling tape with the end of edge piece The peeling angle makes the peeling tape turn back; and a tape collector, so that the peeling tape with useless substances peeled off from the wafer is collected, the tape peeling unit has a holding device, and the protection device is used for when the peeling tape is peeled off. When the end of the edge member stripped from the semiconductor wafer moves beyond a terminal end of the semiconductor wafer, the end of the edge member is prevented from falling.

In the above apparatus, the operation can be performed on the peeling table by continuously supplying the peeling tape to the wafer and peeling off the peeling tape by using the edge member providing a large peeling angle. The release tape can also be provided and collected using a series of steps. In this way, useless substances can be efficiently removed from the surface of the wafer, and therefore, many wafers can be processed continuously.

Thanks to the device for adjusting the angle of the edge piece, the tape can be peeled at the proper peeling angle. Thanks to the holding means, the height of the end of the edge piece can be kept stable, so that the end of the edge piece can maintain a stable height from the beginning to the end of the movement.

In the device for removing useless substances according to the present invention, the tape peeling unit preferably includes: an edge unit, which has an edge member fixed thereon and supported in a swingable manner along the moving direction of the tape peeling unit ; an angle adjusting device, so that adjust the angle of edge member relative to wafer surface; And a holding device, so that the end that prevents edge member from falling when the end of the edge member that peels off strip from wafer moves beyond the terminal end of wafer; Angle adjusting device There is means for swinging the edge unit to adjust the angle of the end of the edge piece; and the retaining means has a means for limiting the vertical movement of the end of the edge piece as the edge unit swings.

The edge unit is supported to be swingable back and forth in a moving direction of the tape peeling unit. The edge unit can be swung by the angle adjustment device, whereby the angle and height of the edge piece can be easily set or changed.

The retaining means limits the vertical movement of the end of the edge piece as the edge unit swings. This will prevent the end of the edge piece from falling off when the end of the edge piece that peels off the release tape moves past the end of the wafer. That is, the peeling tape is prevented from directly adhering to the wafer.

In the device for removing unwanted substances according to the present invention, the peeling angle provided to the peeling tape by the end of the edge member is preferably an acute angle or an obtuse angle. More preferably, the obtuse angle is at least 90 degrees and the acute angle is less than 90 degrees.

In the device for removing unwanted substances according to the present invention, the holding device preferably includes a micrometer.

The apparatus for removing unwanted matter according to the present invention may include means for reciprocating the end of the edge member over the end of the wafer through a small stroke.

Peeling off the strip and the end of the edge piece reaching the end of the wafer reciprocates through a small stroke. As a result, the peel tape can be efficiently peeled and removed from the wafer.

Description of drawings

Fig. 1 is a perspective view of the whole protective tape stripping device in the first embodiment;

Fig. 2 is a front view of the entire protective tape stripping device in the first embodiment;

Fig. 3 is a plan view of the entire protective tape stripping device in the first embodiment;

Fig. 4 is a front view of a tape applying unit and a tape peeling unit;

Figure 5 is a front view showing a support structure for tape peeling edge pieces;

Fig. 6 is a perspective view showing main parts of a tape peeling operation;

Figure 7 is a front view showing the tape stripping process;

Figure 8 is a front view showing the tape stripping process;

Figure 9 is a front view showing a tape stripping process;

Figure 10 is a front view showing a tape stripping process;

Figure 11 is a front view showing a tape stripping process;

FIG. 12 is an enlarged front view of main parts of the tape stripping process;

FIG. 13 is an enlarged front view of main parts of the tape stripping process;

FIG. 14 is an enlarged front view of the main part of the tape stripping process;

FIG. 15 is an enlarged front view of the main part of the tape stripping process;

Fig. 16 is a perspective view showing the entire protective tape stripping device in the second embodiment;

Fig. 17 is a front view of the entire protective tape stripping device in the second embodiment;

Fig. 18 is a plan view of the entire protective tape stripping device in the second embodiment;

Figure 19 is a front view of a tape applying unit and a tape peeling unit;

Figure 20 is a front view showing a support structure for a tape peeling edge piece;

Fig. 21 is a perspective view showing main parts of a tape peeling operation;

Figure 22 is a front view showing the tape stripping process;

Figure 23 is a front view showing the tape stripping process;

Figure 24 is a front view showing the tape stripping process;

Figure 25 is a front view showing the tape stripping process;

Figure 26 is a front view showing the tape stripping process;

Fig. 27 is a front view showing a main part of a tape peeling unit of the device in the third embodiment;

Fig. 28 is a plan view of main parts showing a tape peeling operation of the device in the third embodiment;

Fig. 29 is a front view showing main parts of a tape peeling operation;

30 is an enlarged front view of main parts of a tape stripping process performed by a conventional device;

FIG. 31 is an enlarged front view of main parts of a tape stripping process performed by a conventional device;

32 is a front view of a portion of a beveled semiconductor wafer with a protective tape applied thereto; and

33 is an enlarged front view of a main part of a process performed by a conventional apparatus to peel off a protective tape from a beveled semiconductor wafer after backside grinding.

Detailed ways

The following structure will be used to solve the problems in the prior art.

(first embodiment)

A first embodiment, which is a form for carrying out the present invention, will be described below with reference to the drawings. Fig. 1 is a perspective view showing a whole protective tape stripping device which is an example of a useless substance removing device according to the present invention. Fig. 2 is a front view, and Fig. 3 is a plan view thereof. Fig. 4 is a front view of a tape applying unit and a tape peeling unit. Fig. 5 is a front view showing a supporting structure for a tape peeling edge piece. Fig. 6 is a perspective view showing main parts of a tape peeling operation.

The wafer protection tape removal device includes: a wafer supply station 1, a box C1 for receiving stacked wafers W therein; a wafer transfer mechanism 3 with a manipulator 2; an alignment table 4 for adjusting the position of the wafer W; the peeling tape T is supplied A tape server 5 for a peeling position; a peeling table 6 for supporting a wafer W by suction; a tape applying unit 7 for applying a peeling tape T to the wafer W on the peeling table 6; a tape for peeling off the applied peeling tape T a stripping unit 8; a tape collector 9 for picking up and collecting the stripped stripping tape Ts; and a wafer collecting station 10 for receiving a cassette C2 storing processed wafers 10 in a stacked manner; and a unit driver 11 , which makes the tape applying unit 7 and the tape peeling unit 8 reciprocate left and right independently of each other. These components are mounted on or above the base plate 12 . Wafer supply station 1, wafer transfer mechanism 3, alignment stage 4, stripping stage 6 and wafer collection station 10 are installed on the upper surface of bottom plate 12, while tape server 5 and tape collector 9 are installed on the front surface of vertical wall 13, The vertical wall 13 stands upright on the upper surface of the bottom plate 12 . The tape applying unit 7 and the tape peeling unit 8 are installed near the lower opening of the vertical wall 13 , and the unit driver 11 is installed on the rear side of the vertical wall 13 .

The wafer supply station 1 includes a cassette table 14 for receiving cassettes C1 in which wafers W are stacked in a horizontal manner at appropriate vertical intervals, the surfaces of which have protective tapes P facing upward. Cylinder 15 rotates box table 14 to change its orientation. Wafer collection station 10 also includes a cassette station 16 for supporting cassettes C2 which receive wafers W from which their protective tapes have been stripped, and which are stacked horizontally at appropriate vertical intervals. Box platform 16 also can rotate under the effect of cylinder 17, to change its direction.

The manipulator 2 of the transfer mechanism 3 can move horizontally and pivot, so as to take each wafer W from the wafer supply station 1, provide the wafer W to the alignment stage 4, transfer the wafer W on the alignment stage 4 to the stripping stage 6, and transfer the wafer W on the alignment stage 4 to the stripping stage 6. Each processed wafer W is unloaded from the stage 6 and the processed wafer W is placed into a wafer collection station 10 .

The tape server 5 pulls the stripping tape T from the stock roll R and guides it over the stripping table 6 to the tape applying unit 7 and the tape stripping unit 8 . The peeling tape T used here has a width smaller than the diameter of the wafer W.

As shown in FIG. 3, the peeling table 6 includes a vertically movable suction pad 18 installed at its center, and the pad has an upper surface as a vacuum negative pressure surface. The peeling table 6 has an upward vacuum negative pressure surface to support the wafer W that is not moving.

As shown in FIG. 4 , the tape applying unit 7 includes a movable frame 22 that is supported and can move left and right along a track 21 . Through the feed screw 23 reversibly driven by the motor M1, the moving frame 22 can reciprocate left and right for a fixed stroke. The mobile frame 22 has an application roller 25 , which is supported vertically displaceably via a rocker arm 24 .

The tape peeling unit 8 also includes a movable frame 26 supported to move left and right along the rail 21 . Through the feed screw 27 reversibly driven by the motor M2, the moving frame 26 can reciprocate left and right for a fixed stroke. The moving frame 26 has a tape stripping edge piece 28 , a guide roller 29 , a driven lead-out roller 30 , and a pressure roller 31 opposite thereto.

As shown in Figures 5 and 6, the tape stripping edge member 28 is formed from a plate having a sharp edge formed at its distal end and having a width greater than the diameter of the wafer. The edge member 28 is fixedly connected to a rotatable support shaft 32 which is supported by and protrudes from the front surface of the moving frame 26 . Edge piece 28 is connected by slot 33 and bolt 34 and is adjustable by extension and retraction relative to shaft 32 . The control arm 35 is fixed to the proximal end of the rotation support shaft 32 . The control arm 35 has a free end which is pivotally connected to a link 37 connected to a piston rod 36 a of a cylinder 36 mounted on the front surface of the moving frame 26 . The piston rod 36a is telescopic, thereby swinging the control arm 35, which in turn rotates the rotary support shaft 32, and finally moves the edge member 28 vertically.

A connecting rod 37 extending from the free end of the control arm 35 is screwed to the piston rod 36 a of the cylinder 36 . By adjusting the thread engagement length of the connecting rod 37, the swing angle of the control arm 35 can be adjusted, which is the angle when the piston rod 36a extends to the end of its stroke, that is, the edge member 28 is at the lower extreme position.

The components of the protective tape stripping device according to the present invention are as described above. The basic procedure for peeling off the protective tape P from the surface of the wafer W will be described below with reference to FIGS. 7 to 11. FIG.

First, the robot arm 2 suction-supports a wafer W, takes it out of the cassette C1 at the wafer supply station 1, and places the wafer W on the alignment stage 4. Here, the position of the wafer W is adjusted according to the detected orientation plane of the wafer W or the direction of the notch. The position-adjusted wafer W is then supported and conveyed by the manipulator 2 , and provided to the stripping table 6 .

The wafer W placed on the peeling table 6 is received by the suction pad 18 protruding from the peeling table 6 . When the suction pad 18 is lowered, the wafer W is placed on the upper surface of the peeling table 6 in a predetermined attitude and position, and is supported thereon by the suction force, with the surface of the wafer W on which the protective tape P is applied facing upward. At this time, as shown in FIG. 7 , the tape applying unit 7 and the tape peeling unit 8 are kept at the standby positions that are rearwardly away from the peeling table 6 .

When the wafer W is placed on the peeling table 6, as shown in FIG. 8, the application roller 25 of the tape application unit 7 is lowered to a predetermined level. Then, the entire unit moves forward while the application roller 25 rolls on the wafer W, supplying the release tape T to the surface of the protective tape P.

When the peeling tape T has been supplied, as shown in FIG. 9 , the cylinder 36 of the tape peeling unit 8 is extended to the stroke end, causing the control arm 35 to swing, thereby lowering the edge piece 28 to the lower extreme position.

Next, as shown in FIG. 10, the tape peeling unit 8 moves forward, and the sharp end of the edge piece 28 presses the peeling tape T against the surface of the protective tape P. As shown in FIG. At the same time, the lead-out roller 30 rotates at a peripheral speed synchronized with the moving speed of the unit conveying peeling tape T. As shown in FIG. Thus, the peeling tape T is folded back at an angle θ at the sharp end of the edge member 28 and is guided through the guide roller 29 to a position between the lead-out roller 30 and the pinch roller 31 . As shown in FIG. 6, the peeling tape T takes away the protective tape P firmly adhered thereto, thereby peeling the protective tape P from the surface of the wafer W. As shown in FIG.

Thus, the edge member 28 is set to a forward low speed and begins to peel the protective tape P from the wafer W as it moves past the end thereof. Then, the speed of the forward movement is increased for greater productivity. The lead-out roller 30 is driven by an unillustrated driving device through a slip clutch that slips when the load exceeds a predetermined torque. Thus, the release tape T is detached by applying a predetermined pulling force thereon.

When the tape stripping unit 8 moves past the wafer W and completely strips the protective tape P therefrom, as shown in FIG. inside. Then, the tape applying unit 7 and the tape peeling unit 8 return to the original standby position, and the used peeling tape Ts is rolled up and collected. The applicator roller 25 and edge piece 28 also return upwards to their respective standby positions.

This completes a tape stripping process and the apparatus is ready to process the next wafer.

The process of peeling off the protective tape P from a thin wafer W which is back ground to a bevel b (see FIG. 32) will be described below with reference to FIGS. 12 to 15. FIG.

As shown in FIG. 12, the sharp end of the edge piece 28 at the lower extreme position is slightly below the surface of the protective tape P. As shown in FIG. Thus, when a thin wafer W having a bevel b is handled and the protruding end Pa of the protective tape P is bonded to the bevel, the sharp end of the edge piece 28 near the end of the wafer W also provides the release tape T to the bevel. The protruding end Pa of the tape P is protected.

Thus, when the edge member 28 is moved forward to be located at the end of the wafer W, as shown in FIG. The subsequent stripping process was performed stably, as shown in FIG. 15 .

Preferably, the bending angle θ provided by the edge member 28 is set to be an obtuse angle of 90 degrees or more, more preferably 100 degrees or more. However, depending on the adhesion or toughness or strength of the wafer W, this angle may be less than 90 degrees (closer to 90 degrees). Preferably, the greater the toughness of the protective tape P, the smaller the bending angle θ of the tape. This adjustment can be achieved by adjusting the extension of the link 37 and thus the angle of the edge piece 28 in the lower extreme position. A change in the height of the edge member due to a change in the angle of the edge member 28 can be corrected by adjusting the mounting position of the edge member 28 relative to the rotational support shaft 32 .

(second embodiment)

A second embodiment will be described below with reference to the drawings.

Fig. 16 is a perspective view showing the entire protective tape stripping device, which is an example of a useless substance removing device according to the present invention. Fig. 17 is a front view, and Fig. 18 is a plan view thereof. Fig. 19 is a front view of the tape applying unit and the tape peeling unit. Figure 20 shows a front view of a support structure for a tape peel edge piece. Fig. 21 is a perspective view showing main parts of a tape peeling operation.

This embodiment differs from the first embodiment only in the tape peeling unit 8 . The same parts as those in the first embodiment are denoted by the same reference numerals and will not be described here.

The tape stripping unit 8 includes a moving frame 26 that can move left and right along the track 21 through a fixed stroke. The moving frame 26 has a tape stripping edge piece 28, an angle adjustment roller 29, a driven lead-out roller 30 and a pinch roller 31 opposite thereto.

As shown in FIGS. 20 and 21, the tape peeling edge member 28 is formed of a flat plate having a sharp edge formed at its distal end and having a width greater than the diameter of the wafer. The edge member 28 is fixedly connected to a rotatable support shaft 32 which is supported by the front surface of the moving frame 26 and protrudes therefrom. The edge piece 28 is connected with the bolt 34 through the notch 33 and can adjust its expansion and contraction relative to the shaft 32 .

A control arm 35 is fixed at the distal end of the rotation support shaft 32 . The control arm 35 has a free end that is pivotally connected to a link 37 connected to a piston rod 36 a of a cylinder 36 mounted on the front surface of the moving frame 26 . The piston rod 36a is retractable to swing the control arm 35, and the control arm 35 rotates the rotary support shaft 32 to move the edge of the edge member 28 vertically.

A connecting rod 37 extending from a free end of the control arm 35 is screwed to a piston rod 36 a of the cylinder 36 . By adjusting the thread engagement length of the connecting rod 37, the swing angle of the control arm 35 can be adjusted. This adjustment occurs when the piston rod 36a extends to the end of its stroke, that is, when the edge member 28 is in the lower extreme position.

The angle adjustment roller 29 is a rotatable roller, and it is connected with a connecting rod 39 screwed on the piston rod 38a of the cylinder 38 . That is, the position of the angle adjusting roller 29a can be adjusted as desired by adjusting the screw engagement amount of the link 39, thereby adjusting the belt bending angle θ.

Preferably, the greater the toughness of the protective tape P or the greater the toughness of the peeling tape T, the smaller the belt bending angle θ set by the angle adjusting roller 29 .

The basic process of peeling the protective tape P from the surface of the wafer W will be described below with reference to FIGS. 22 to 26 . The process of supplying the wafer W to the peeling table 6 is the same as that of the first embodiment. Thus, the process will be described with reference to that shown in FIG.

When the wafer W has been placed on the peeling table 6, as shown in FIG. 23, the application roller 25 of the tape application unit 7 is lowered to a predetermined height. Then, the entire unit moves forward while the application roller 25 rolls on the wafer W, supplying the release tape T to the surface of the protective tape P.

When the peeling tape T is supplied, as shown in FIG. 24 , the cylinder 36 of the tape peeling unit 8 is extended to the stroke end, causing the control arm 35 to swing, thereby lowering the edge member 28 to the lower limit position. At the same time, the cylinder 38 contracts to the stroke end, thereby setting the angle adjusting roller 29 at an angle θ. In this embodiment, the angle θ is an acute angle of 90 degrees or less.

Next, as shown in FIG. 25, the tape peeling unit 8 moves forward, and the sharp end of the edge piece 28 presses the peeling tape T against the surface of the protective tape P. As shown in FIG. At the same time, the lead-out roller 30 rotates at a peripheral speed synchronized with the moving speed of the unit conveying the peeling tape T. As shown in FIG. Thus, the peeling tape T is turned back at the angle θ at the angle regulating roller 29 and is guided to a position between the lead-out roller 30 and the pinch roller 31 by the regulating roller 29 . As shown in FIG. 21, the peeling tape T takes away the protective tape fixedly bonded thereto, thereby peeling the protective tape P from the surface of the wafer W. As shown in FIG.

Thus, the edge member 28 is set to a forward low speed and begins to peel the protective tape P from the wafer W as it moves past the end thereof. Then, the speed of the forward movement is increased for greater productivity. The lead-out roller 30 is driven by an unillustrated driving device through a slip clutch that slips when the load exceeds a predetermined torque. Thus, the release tape T is detached by a predetermined pulling force applied thereto.

When the tape stripping unit 8 moves past the wafer W and completely strips the protective tape P therefrom, as shown in FIG. inside. Then, the tape applying unit 7 and the tape peeling unit 8 return to the original standby position, and the used peeling tape Ts is rolled up and collected. The applicator roller 25 and edge piece 28 also return upwards to their respective standby positions.

This completes a tape stripping process and the apparatus is ready to process the next wafer.

(third embodiment)

A third embodiment will be described below with reference to the drawings.

Fig. 27 is a front view showing the main part of the tape peeling unit. Fig. 28 is a plan view of main parts of the tape peeling unit.

This embodiment differs from the first embodiment only in the tape peeling unit 8 . The same parts as those in the first embodiment are denoted by the same reference numerals and will not be described here.

As shown in FIG. 27, the tape peeling edge member 28 is made of a flat plate having a sharp edge formed at its distal end and having a width greater than the diameter of the wafer. The edge piece 28 is fixed to an edge unit 41 supported by a rotation shaft 40 of the tape peeling unit 8 . A release tape transfer roller R is also installed.

The edge unit 41 has a piston rod 36 a of a cylinder 36 connected to its sides by connecting rods 37 . As the piston rod 36a expands and contracts, the edge unit 41 swings forward and backward in the moving direction of the edge piece 28 . As a result, the edge of edge piece 28 moves vertically, thereby changing its angle and its height. The cylinder 36, the piston rod 36a and the connecting rod 37 in this embodiment constitute the angle adjusting device of the present invention.

The torque drive of the pulse motor PM is transmitted to the end of the edge unit 41 remote from the cylinder 36 . The edge unit 41 has two micrometers 43 fixed on its left and right sides, and the adjustment rod 44 is expandable and contractible in response to the reversible rotation of the pulse motor PM.

Specifically, as shown in FIG. 28, two micrometers 43 are driven by torques of equal rotational speed through a belt V wrapped around a pulley K coaxial with the gear G from a single pulse motor PM. That is, the rotation of the pulse motor PM is directly transmitted to a gear G and then to a micrometer 43 . This rotation is transmitted to another gear G through a belt V and then to another micrometer 43 . The adjusting rod 44 of the left and right micrometers 43 can be telescopically the same distance.

The ends of the adjustment rod 44 of the micrometer 43 are close to both sides of the frame of the edge unit 41 . The edge unit 41 is inclined to a predetermined angle by the piston rod 36a. The adjustment lever 44 close to the frame of the edge unit 41 acts as a stop preventing the edge unit 41 from tilting beyond a predetermined angle, moving the edge vertically, especially downward. By fixing the position of the edge unit 41 as described above, the following troubles can be avoided.

At the time of the peeling operation, as the edge comes into contact with the surface of the peeling tape T, the edge pushes the peeling tape T. When the edge, which has reached the end of the wafer W, moves past the end, without fixing the position of the edge unit 41, the edge will tilt down to a considerable extent as shown in FIG. touch. Due to this phenomenon, the adhesive surface of the peeling tape T will be bonded to the end of the wafer W again as the protective tape P is peeled off. When the peeling unit 8 returns at this stage, the end of the wafer W will be bent upward, which will cause damage.

In this embodiment, the above-mentioned troubles can be avoided because the edge unit 41 is fixed by the adjustment rod 44, preventing it from moving vertically.

The peeling angle of the edge unit 41, that is, the end position of the edge can be appropriately changed according to the thickness of the protective tape P and the thickness of the peeling tape T provided to the wafer W. The adjusting rod 44 does not need to be kept in contact with the edge unit 41, but can provide a gap (gap) according to the thickness of the two tapes in order to prevent the peeling tape T from sticking to the surface of the wafer W. The micrometer 43 corresponds to the holding means of the present invention.

The operation of peeling off the protective tape is the same as the above embodiment, so it will not be described again.

The present invention is not limited to above-mentioned embodiment, also can change as follows:

(1) When reaching the end of the wafer W, the edge member 28 can reciprocate a predetermined small stroke back and forth. Then, the peeling tape T can be supplied to the end of the protective tape P with increased reliability, so that a substantially complete peeling can be effectively performed. This will be particularly effective when processing wafers W with beveled sides b.

(2) The supply of the peeling tape T to the protective tape P at the end of the wafer W can be monitored by a CCD camera or the like. A predetermined peeling operation may be started after it is determined that a peeling tape has been supplied to the end of the protective tape P. As shown in FIG.

(3) The present invention is also applicable to the case where the protective tape P is peeled off from the wafer W supported by the ring frame with an adhesive tape.

(4) The present invention is also applicable to the case where the stripping band is directly provided to the surface of the wafer to remove the useless protective layer (useless substance) remaining on the wafer surface.

(5) The holding means for stabilizing the edge height of the edge member 28 in the third embodiment is not limited to the micrometer 43 . The device may have any other structure so as to prevent the peeling tape T from sticking directly to the wafer W during a series of operations of peeling the peeling tape T from the wafer W.

(6) The tape peeling unit 8 in the third embodiment adjusts the height and angle of the edge of the edge piece 28 by swinging the edge unit 41 . This structure is not limiting. For example, only the edge piece 28 is individually adjustable to change the angle.

industrial application

As described above, the apparatus for removing useless substances from semiconductor wafers according to the present invention peels and removes useless substances from wafers by using a peeling tape so that the wafers are not broken or damaged by the peeling force of the tape.

Claims (17)

1. A method of stripping off useless substances from semiconductor wafers by providing stripping strips to semiconductor wafers, removing useless substances from semiconductor wafers, and stripping useless substances from semiconductor wafers together with stripping strips, characterized in that the method comprises the following steps: placing an edge piece in contact with the surface of a release tape provided to the semiconductor wafer, and peeling off the release tape while being folded back at a peel angle provided by the end of the edge piece, and When the end of the edge member moves beyond a terminal end of the semiconductor wafer, the end of the edge member is prevented from falling. 2. The method of removing useless substances according to claim 1, wherein said peeling angle provided to said peeling tape by the end of said edge member is an acute angle. 3. The method of removing unwanted matter according to claim 2, wherein said stripping angle at the end of said edge piece is at least 90 degrees. 4. The method of removing useless substances according to claim 1, wherein said peeling angle provided to said peeling tape by the end of said edge member is an obtuse angle. 5. The method of removing useless substances according to claim 4, wherein the peeling angle at the end of the edge piece is less than 90 degrees. 6. The method of removing unwanted substances according to claim 1, wherein the tip of the edge member reciprocates over a short stroke at the end of the semiconductor wafer. 7. The method for removing unnecessary substances according to claim 1, wherein the unnecessary substances on the semiconductor wafer are protective tapes applied on the surface of the semiconductor wafer. 8. The method for removing unnecessary substances according to claim 1, wherein the unnecessary substances on the semiconductor wafer are a protective layer formed on the surface of the semiconductor wafer. 9. A device for removing unwanted substances from a semiconductor wafer, comprising: a lift-off table supporting the semiconductor wafer; a tape server that provides stripping strips to semiconductor wafers on the stripping station; a tape applicator unit that receives the release tape and provides the release tape to the semiconductor wafer; A tape stripping unit having edge pieces so as to peel off the stripping tape from the semiconductor wafer, it starts from the end of the semiconductor wafer and folds back the stripping tape by the peeling angle provided by the end of the edge piece to the stripping tape; and A tape collector to collect the peeled tape with unwanted material from the wafer; The tape peeling unit has a holding device for preventing the tape from being peeled off from the semiconductor wafer when the end of the edge member moves beyond a terminal end of the semiconductor wafer. The end of the edge piece falls down. 10. The apparatus for removing unwanted substances as claimed in claim 9, wherein said tape stripping unit has a means for adjusting the angle of said edge member relative to the wafer surface. 11. The device for removing useless substances as claimed in claim 9, wherein the tape stripping unit comprises: An edge unit having an edge member fixed thereon and supported in a swingable manner along the moving direction of the tape peeling unit; an angle adjustment device to adjust the angle of the edge member relative to the wafer surface; and a retaining means to prevent the end of the edge piece from falling down when the end of the edge piece which peels off the peel tape from the wafer moves beyond the end of the wafer; said angle adjusting means has means for swinging said edge unit so as to adjust the angle of the end of the edge piece; and The retaining means has a member to limit the vertical movement of the edge piece tip following the swinging of the edge unit. 12. The device for removing unwanted substances as claimed in claim 9, wherein the peeling angle provided by the end of said edge member to the peeling tape is an acute angle. 13. The unwanted material removal device of claim 12, wherein said stripping angle at the end of the edge member is at least 90 degrees. 14. The device for removing unwanted substances according to claim 9, wherein the peeling angle provided by the end of said edge member to the peeling tape is an obtuse angle. 15. The device for removing unwanted matter according to claim 14, wherein said stripping angle at the end of the edge member is less than 90 degrees. 16. The device for removing unwanted matter according to claim 9, wherein said holding means comprises a micrometer. 17. The unwanted material removal apparatus of claim 9, further comprising means for reciprocating the tip of said edge member over a small stroke at the end of the wafer.

Images