JP4498085B2 - Protective tape cutting method and apparatus using the same - Google Patents

Description

  The present invention relates to a protective tape cutting method capable of accurately cutting a protective tape for surface protection attached to a surface of a semiconductor wafer before back grinding, and an apparatus using the same.

  As a means of thinning a semiconductor wafer (hereinafter simply referred to as “wafer”), the back surface of the wafer is processed using a mechanical method such as grinding or polishing, or a chemical method using etching, and the thickness is reduced. It is thin. Further, when a wafer is processed using these methods, a protective tape is attached to the surface of the wafer in order to protect the wafer surface on which the wiring pattern is formed.

That is, the wafer transferred to the back grinding process has its front surface (pattern surface) sucked and held by the chuck table, and its back surface is ground by the grindstone. At this time, since stress due to grinding is applied to the surface of the wafer and the pattern may be damaged or soiled, a protective tape is attached to the surface. In this protective tape, a roll-shaped belt-shaped protective tape is supplied to the wafer surface, and a sticking roller is rolled along the wafer surface so that the protective tape is sequentially attached to the wafer surface from one end thereof. Thereafter, the protective tape is cut by a cutter blade along the wafer outer shape (see, for example, Patent Document 1).
JP-A-8-217320

  However, the conventional protective tape cutting method has the following problems.

  That is, while the protective tape affixed to the wafer is being cut by the cutter blade, the end surfaces of the protective tape affixed to the wafer after cutting and the end surfaces of the surplus protective tape flutter up and down and come into contact with each other , Generate foreign matter and particles. Further, the adhesive at the end of the excess protective tape, the generated foreign matter, and the like adhere to the surface and end surface of the protective tape attached to the wafer.

  In this way, when foreign matter such as adhesive adheres to the surface or end face of the protective tape, if the surface is adsorbed and held and back-grinded on the back, the wafer will be the height of the adhesive attached to the surface. The back side of the machine will be ground excessively. That is, there is a problem that the thickness of the wafer is non-uniform and the back surface processing accuracy is lowered.

  The present invention has been made in view of such circumstances, and a protective tape cutting method capable of accurately cutting a protective tape attached to the surface of a semiconductor wafer to suppress the generation of foreign matters and the like. The main object is to provide a device using the above.

The first invention is a protective tape cutting method for cutting a protective tape attached to the surface of a semiconductor wafer on which a pattern is formed by moving a cutter blade along the outer periphery of the semiconductor wafer,
While cutting the protective tape with the cutter blade, the end of the excess protective tape after cutting is positively bent downward by a bending means .

  (Operation / Effect) According to this method, while cutting the protective tape with the cutter blade, the end portion of the surplus protective tape after cutting is bent, so that the end portions of the protective tape attached to the wafer and the end portions of the surplus protective tape are There is no contact. Therefore, foreign matter and particles generated by contact between the ends of both protective tapes can be eliminated, and as a result, the foreign matter does not adhere to the surface and end surfaces of the protective tape affixed to the wafer, and the thickness of the semiconductor wafer. The backgrinding process can be performed in a state in which is kept uniform.

  In addition, it is preferable to bend | fold so that the non-adhesive surface of an excess protection tape edge part and the side surface of a cutter blade may substantially oppose as bending of the edge part of the excess protection tape after a cutting | disconnection. For example, it may be bent by sucking from the adhesive surface side of the surplus protective tape end, or may be bent by pressing the non-adhesive surface of the end of the surplus protective tape with a pressing member.

  When suctioning the adhesive surface side of the end of the excess protective tape, the end of the excess protective tape that has fluttered after cutting is positively sucked and bent so that the adhesive surface faces outward with respect to the side of the cutter blade. maintain. Therefore, the ends of the two protective tapes after cutting do not come into contact with each other, and the adhesive does not adhere to the surface of the protective tape attached to the wafer. Furthermore, if the end of the excess protective tape is continuously sucked while the protective tape is being cut, the foreign matter generated when the protective tape is cut can be removed by suction. That is, it is possible to reliably suppress the adhesion of foreign matters or the like to the surface of the protective tape.

  In addition, even when the non-adhesive surface of the end portion of the excess protective tape is pressed and bent by the pressing member, the end portion of the excess protective tape that has been fluttered after cutting is actively bent by the pressing member, and the adhesive surface becomes the side surface of the cutter blade. Maintain a posture facing outward. Therefore, the ends of the two protective tapes after cutting do not come into contact with each other, and the adhesive does not adhere to the surface of the protective tape attached to the wafer. That is, according to this method, the first invention can be suitably implemented.

4th invention is a protective tape cutting device which cut | disconnects the protective tape affixed on the surface of the semiconductor wafer in which the pattern was formed,
Holding means for sucking and holding the semiconductor wafer;
Protective tape attaching means for attaching a protective tape to the surface of the semiconductor wafer sucked and held by the holding means;
A protective tape cutting means comprising a cutter blade, and cutting the protective tape attached to the surface of the semiconductor wafer by moving the cutter blade through the protective tape and moving along the outer periphery of the semiconductor wafer;
Bending means for bending the end portion of the excess protective tape after being cut by the protective tape cutting means so that the non-adhesive surface and the side surface of the cutter blade are substantially opposed to each other;
It is provided with.

  (Operation / Effect) According to the fourth invention, the holding means sucks and holds the semiconductor wafer. The protective tape affixing unit affixes the protective tape on the surface of the semiconductor wafer sucked and held by the holding unit. The protective tape cutting means includes a cutter blade, and cuts the protective tape attached to the surface of the semiconductor wafer by moving the cutter blade along the outer periphery of the semiconductor wafer through the protective tape. The bending means bends the end portion of the surplus protective tape after being cut by the protective tape cutting means so that the non-adhesive surface and the side surface of the cutter blade substantially face each other.

  According to this configuration, the protective tape is attached to the surface of the semiconductor wafer sucked and held by the holding means by the protective tape attaching means, and the cutter blade of the protective tape cutting means is passed through the attached protective tape to make the semiconductor wafer. By moving along the outer periphery of the semiconductor wafer, a protective tape cut in substantially the same shape as the semiconductor wafer is attached to the surface of the semiconductor wafer. In the process of cutting the protective tape, the end portion of the cut excess protective tape is bent downward by the bending means so that the non-adhesive surface and the side surface of the cutter blade are substantially opposed to each other. That is, while the protective tape is being cut, the ends of the two protective tapes after being cut do not come into contact with each other. As a result, the generation of foreign matter and particles can be eliminated, and as a result, the protective tape is attached to the semiconductor wafer. The adhesion of these foreign substances to the surface of the attached protective tape is eliminated, and the back grinding process can be performed in a state where the thickness of the semiconductor wafer is kept uniform.

  In addition, it is preferable that a bending means is a suction means to attract from the adhesive surface side of the excess protection tape edge part after a cutting | disconnection. According to this configuration, the end portion of the surplus protective tape that has fluttered after being cut is actively bent downward by the suction means, and the posture in which the adhesive surface faces outward with respect to the side surface of the cutter blade is maintained. Therefore, the second invention can be suitably realized.

  Further, the bending means is, for example, a roller that rolls in the moving direction of the cutter blade, and the roller may be provided on the side surface or the rear side of the cutter blade. The bending member which has the inclined surface extended toward the direction may be sufficient.

  According to this configuration, the end portion of the surplus protective tape immediately after being cut is positively bent downward by the roller or the bending member, and the end portion of the surplus protective tape that has been fluttered after the cut is formed on the side surface of the cutter blade. On the other hand, the posture facing outward can be maintained. That is, it can suppress that the edge parts of both the protection tapes after cutting | disconnection contact during the cutting | disconnection of a protection tape.

  According to the protective tape cutting method and the apparatus using the same according to the present invention, the end of the surplus protective tape after cutting is bent while cutting the protective tape with the cutter blade, The ends of both protective tapes do not contact each other. Therefore, foreign matter and particles generated by contact between the ends of both protective tapes can be eliminated, and as a result, the foreign matter does not adhere to the surface of the protective tape attached to the wafer, and the thickness of the semiconductor wafer is uniform. The backgrinding process can be performed in a state kept at

  Embodiments of a protective tape applying apparatus provided with the protective tape cutting apparatus of the present invention will be described below with reference to the drawings.

  FIG. 1 is a perspective view showing the overall configuration of the protective tape attaching device, and FIG. 2 is a perspective view showing the main part thereof.

  As shown in FIGS. 1 and 2, a protective tape attaching apparatus 1 according to this embodiment includes a wafer storage unit that stores a semiconductor wafer 2 (hereinafter simply referred to as “wafer”) that is an article to which the protective tape is attached. 11a, 11b, a robot arm 12 serving as a transfer means for transferring the wafer 2 from the wafer storage units 11a, 11b, an alignment stage 14 for placing and positioning the wafer 2 transferred by the robot arm 12, and the positioning A holding table 3 which is a holding means for holding the wafer 2, a tape supply unit 5 for supplying the protective tape 4 to the wafer 2 placed on the holding table 3, and releasing the protective tape 4 from the release liner 6. Supplied from a release mechanism section 7, a liner take-up section 8 for winding the release liner 6 released by the release mechanism section 7, and a tape supply section 5. There is no need for a sticking mechanism 9 that is a sticking tape sticking means for sticking the protective tape 4 on the wafer, a protective tape cutting means 10 for cutting the protective tape 4 attached to the wafer 2 along the outer periphery of the wafer 2, and the like. The unnecessary tape winding portion 15 for winding the protective tape 4 is configured as a main portion.

  The wafer storage portions 11a and 11b can store and place the wafers 2 in multiple stages. At this time, the wafer 2 maintains a horizontal posture with the pattern surface facing upward.

  The robot arm 12 is configured to bend and rotate so as to be able to advance and retract horizontally while being turned by a drive mechanism (not shown). A wafer holding part 17 having a horseshoe shape is provided at its tip. The wafer holding unit 17 is provided with a suction hole (not shown), and the wafer 2 is vacuum-sucked from the back surface by the suction hole.

  That is, the robot arm 12 sucks and holds the wafer 2 from the back surface by the wafer holding unit 17 moving back and forth through the gap between the wafers stored in multiple stages in the wafer cassettes 11a and 11b, and positioning the wafer 2 held by suction as described later. The alignment stage 14, which is a means, the holding table 3, and the wafer cassettes 11a and 11b are transferred in this order.

  The alignment stage 14 aligns the placed wafer 2 based on an orientation flat formed on the outer shape thereof.

  As shown in FIGS. 3 and 4, the holding table 3 includes a holding member 20 that places and holds the wafer 2, and a cutter blade 35 of the protective tape cutting unit 10 that cuts the protective tape 4 on the outer periphery of the holding member 20. The outer peripheral member 21 is provided so as to be adjacent to form the protective tape cutting groove 22 to be inserted. The holding member 20 and the outer peripheral member 21 are arranged such that when the wafer 2 is placed on the holding member 20, the surface of the wafer 2 and the surface of the outer peripheral member 21 form substantially the same surface. The protective tape 4 is attached to the surface of the wafer 2 and the surface of the outer peripheral member 21 simultaneously by a series of steps of the attaching mechanism unit 9. Further, the holding member 20 and the outer peripheral member 21 are respectively disposed on the holding table 3, and the outer peripheral member 21 is formed as a separate member from the holding table 3. That is, the outer peripheral member 21 is not formed integrally with the holding table 3 but is formed so as to be splittable. In addition, although it is preferable to arrange | position so that the height of the outer periphery member 21 may become substantially the same surface as the wafer 2 surface, it is not limited to this. Moreover, the outer peripheral member 21 may be configured by a plurality of divided members.

  The upper corner of the inner wall of the outer peripheral member 21 that forms the protective tape cutting groove 22 is rounded. Further, an exhaust pipe 41 having an electromagnetic valve 40 is connected to the bottom of the protective tape cutting groove 22. Further, the exhaust pipe 41 has a base end portion connected to the exhaust means 42 in communication. In other words, while the protective tape 4 attached to the surface of the wafer 2 sucked and held by the holding table 3 is being cut by the cutter blade 35, it is connected to the protective tape cutting groove 22 to which the cutter blade 35 moves. By opening the electromagnetic valve 40 of the exhaust pipe 42 thus made via the control unit 43 and driving the exhaust means 42, the end portion of the cut surplus protective tape 4 becomes as shown in FIG. It hangs down due to its own weight and is sucked downward by the exhaust inside the groove and is actively bent downward along the roundness of the outer peripheral member 21. That is, the adhesive surface at the end of the cut excess protective tape 4 is sucked and bent so as to face outward with respect to the side surface of the cutter blade 35.

  Returning to FIG. 1 and FIG. 2, the tape supply unit 5 winds and guides the protective tape 4 with the release liner 6 fed from the tape bobbin 31 to the release mechanism unit 7 constituted by a guide roller group. The tape supply unit 5 is pivotally supported on the vertical wall of the apparatus main body and is restricted from rotating through a brake mechanism or the like.

  The release liner winding unit 8 includes a recovery bobbin 32 that is linked to a driving mechanism such as a motor, and a guide roller group that is pivotally supported on the vertical wall of the apparatus main body.

  The tape application mechanism unit 9 is held by a rail of the apparatus main body so that a frame (not shown) can slide in the tape running direction, and is interlocked and connected via a drive unit such as a motor. A sticking roller 33 is rotatably supported on the frame, and the sticking roller 33 is driven to swing up and down by a cylinder (not shown). That is, the sticking roller 33 pushes the surface of the protective tape 4 and rolls the protective tape 4 on the surface of the wafer 2 while rolling.

  The protective tape cutting means 10 includes a cutter unit 26 attached to the ball shaft 34 so as to be movable up and down, a lift drive unit 27 that moves the cutter unit 26 up and down, and a control unit (not shown) that controls the lift drive unit 27. It is configured.

  The cutter unit 26 is connected at one end to an arm 28 that is cantilevered by an elevating drive unit 27, a motor 29 attached to the upper end of the arm 28, and a rotating shaft of a motor 29 that penetrates the arm 28 downward. And a cutter blade 35 attached downward so as to be turnable.

  The elevating drive unit 27 moves up and down along the ball shaft 34. Note that a stopper for regulating the lowermost position (height) of the lifting drive unit 27 is provided at the bottom of the ball shaft 34, although not shown.

  The motor 29 transmits the rotational force to the cutter blade 35 via the rotation shaft, and turns the cutter blade 35.

  The unnecessary tape peeling mechanism unit 30 is held by a rail of the apparatus main body so that a frame (not shown) can slide in the tape running direction, and is interlocked and connected via a driving unit such as a motor. A peeling roller 36 is rotatably supported on the frame, and the peeling roller 36 is driven to swing up and down by a cylinder (not shown). The peeling roller 36 is for peeling off the unnecessary protective tape 4 after being cut along the outer periphery of the wafer 2 from the wafer 2.

  The unnecessary tape take-up unit 15 has a recovery bobbin 37 pivotally supported on the vertical wall of the apparatus 1 and is linked to a drive unit such as a motor. In other words, a predetermined amount of the protective tape 4 is fed out from the tape supply unit 5 and supplied onto the wafer, and the unnecessary protective tape 4 after cutting is wound around the recovery bobbin 37 by operating the drive unit. It has become.

  Next, a series of operations when cutting the protective tape using the above-described apparatus will be described with reference to FIGS.

  The robot arm 12 takes out the wafer 2 to be taken out of the wafer storage portions 11a and 11b in which the wafers 2 are stored in multiple stages. At this time, the wafer holding unit 17 of the robot arm 12 is inserted into the gap between the wafers in the wafer storage units 11a and 11b. The robot arm 12 picks up and holds the wafer 2 from the back surface by the wafer holding unit 17 and transfers the wafer 2 to the alignment stage 14.

  The wafer 2 placed on the alignment stage 14 is aligned based on an orientation flat, a notch or the like. After the alignment, the wafer 2 is transferred to the holding table 3 while the back surface is sucked and held by the robot arm 12.

  The wafer 2 placed on the holding member 20 on the holding table 3 is aligned and sucked and held. At this time, as shown in FIG. 6, the sticking mechanism portion 9 and the tape peeling mechanism portion 30 of the protective tape 4 are located at the initial position, and the cutter unit 26 is located at the upper standby position.

  When the alignment of the wafer 2 is completed, the sticking roller 33 of the sticking mechanism portion 9 of the protective tape 4 swings down, and the sticking roller 33 presses the protective tape 4 while pressing the protective tape 4 as shown in FIG. It rolls in the direction opposite to the tape running direction, and the protective tape 4 is evenly attached to the entire surface of the wafer 2. When the sticking mechanism 9 of the protective tape 4 reaches the end position, the sticking roller 33 moves up.

  Next, as shown in FIG. 8, the cutter unit 26 descends to the protective tape cutting position, and the cutter blade 35 pierces and penetrates the protective tape cutting groove 22 of the protective tape 4. At this time, the cutter blade 35 penetrating the protective tape 4 is stopped at a predetermined position (height). Further, the electromagnetic valve 40 provided in the exhaust pipe 41 connected to the protective tape cutting groove 22 on which the cutter blade 35 travels is opened, and the exhaust means 42 is driven to exhaust the exhaust gas in the protective tape cutting groove. I do. Then, the cutter blade 35 stopped at the predetermined position moves along the outer periphery of the wafer 2 in a state where the exhaust in the protective tape cutting groove is performed. That is, the protective tape 4 is cut along the outer periphery of the wafer 2. Therefore, the end portion of the surplus protective tape 4 after being cut by the cutter blade 35 hangs down by its own weight and is sucked downward along with the exhaust in the protective tape cutting groove, along the inner wall of the outer peripheral member 21. It is actively bent downward.

  After the protective tape 4 is cut, the cutter unit 26 rises and returns to the standby position.

  Next, as shown in FIG. 9, the unnecessary tape peeling mechanism unit 30 rolls up and peels off the unnecessary protective tape 4 cut on the wafer while moving on the wafer in the direction opposite to the tape running direction.

  When the unnecessary tape peeling mechanism part 30 reaches the end position of the peeling work, the unnecessary tape peeling mechanism part 30 and the sticking mechanism part 9 move in the tape running direction and return to the initial position. At this time, the unnecessary protective tape 4 is wound around the recovery bobbin 37 by the winding roller 16. At the same time, the protective tape 4 is fed out from the tape supply unit 5 together with a fixed amount of the release liner 6, and is separated into the release liner 6 and the protective tape 4 when passing through the release mechanism unit 7. This completes one round of operation of attaching the protective tape 4 to the surface of the wafer 2.

  As described above, the protective tape 4 attached to the surface of the wafer 2 is evacuated in the groove for cutting the protective tape while the protective tape 4 is cut by the cutter blade 35, so that the excess protective tape 4 after being cut is removed. The end is sucked downward and positively bent. As a result, the ends of the two protective tapes 4 after being cut can come into contact with each other to suppress the generation of foreign matter and particles, and the foreign matter generated at the time of cutting is sucked and discharged from the protective tape cutting groove 22. . Therefore, no foreign matter or the like adheres to the surface of the protective tape 4 attached to the wafer 2, so that in the subsequent back grinding process, the surface of the wafer 2 can be adsorbed in a flat state and subjected to a grinding process. As a result, the thickness of the wafer 2 can be made uniform.

  The present invention is not limited to the embodiment described above, and can be modified as follows.

  (1) In the above embodiment, the end of the cut protective tape 4 is sucked downward by positively sucking from the lower part of the protective tape cutting groove 22 and exhausting the inside of the protective tape cutting groove. However, it may be configured as follows.

  For example, as shown in FIGS. 10 and 11, a roller 45 that rolls in the traveling direction of the cutter blade 35 is disposed on the side surface side of the cutter blade 35, and the end portion of the excess protective tape 4 after being cut is a roller 45. Further, it may be sandwiched between the inner walls of the outer peripheral member 21 and actively bent downward.

  Further, as shown in FIGS. 12A and 12B, a bending member 46 having an inclined surface extending obliquely outward rearward from the front end side of the cutter blade 35 is provided on the side surface of the cutter blade 35 on the side not contacting the outer periphery of the wafer 2. A configuration may be used. According to this configuration, the end portion of the surplus protective tape 4 guided outward by the bending member 46 is sandwiched between the bending member 46 and the inner wall of the outer peripheral member 21 and actively bent downward. The bending member 46 may be plate-shaped or block-shaped.

  If comprised as mentioned above, since the edge part of the surplus protection tape 4 after a cut | disconnect will be maintained in the state bent below, the edge parts of both protection tapes will contact, while the protection tape 4 is cut | disconnected. There is nothing. That is, the same effect as the above-described embodiment is obtained.

  (2) The exhaust in the protective tape cutting groove and the roller 45 or the bending member 46 may be combined.

  (3) The upper corner portion of the inner wall of the outer peripheral member 21 of the above embodiment has been rounded, but the corner portion has a right angle or an acute angle, and the end of the surplus protective tape is creased. It may be configured to be bent.

It is a perspective view which shows the whole protective tape sticking apparatus. It is a perspective view which shows the principal part of a protective tape sticking apparatus. It is a top view of a holding table. It is sectional drawing of a holding table. It is a figure which shows the cutting state of a protective tape. It is a schematic front view which shows the sticking operation | movement of a protective tape. It is a schematic front view which shows the sticking operation | movement of a protective tape. It is a schematic front view which shows the sticking operation | movement of a protective tape. It is a schematic front view which shows the sticking operation | movement of a protective tape. It is a side view around the cutter blade of a modification. It is a figure which shows the protective tape cutting | disconnection operation | movement of a modification. It is a side view around the cutter blade of a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 ... Semiconductor wafer 3 ... Holding table 4 ... Protection tape 10 ... Protection tape cutting | disconnection part 20 ... Holding part 21 ... Outer peripheral member 22 ... Groove for protection tape cutting | disconnection 30 ... Pasting roller 35 ... Cutter blade 41 ... Exhaust pipe line 42 ... Exhaust means

Claims (9)

A protective tape cutting method for cutting a protective tape attached to the surface of a semiconductor wafer on which a pattern is formed by moving a cutter blade along the outer periphery of the semiconductor wafer,
A protective tape cutting method, wherein the end portion of the excess protective tape after being cut is positively bent downward by a bending means while cutting the protective tape with the cutter blade. In the protective tape cutting method according to claim 1,
The protective tape cutting method, wherein the end of the surplus protective tape after cutting is folded so that the non-adhesive surface of the end of the surplus protective tape and the side surface of the cutter blade are substantially opposed to each other. In the masking tape cutting method according to claim 1 or 2,
A method of cutting a protective tape, characterized in that bending of the end portion of the excess protective tape after cutting is performed by suction from the adhesive surface side of the end portion of the excess protective tape. In the masking tape cutting method according to claim 1 or 2,
The protective tape cutting method, wherein the bending of the end portion of the surplus protective tape after cutting is performed by pressing the non-adhesive surface of the end portion of the surplus protective tape with a pressing member. A protective tape cutting device for cutting a protective tape attached to the surface of a semiconductor wafer on which a pattern is formed,
Holding means for sucking and holding the semiconductor wafer;
Protective tape attaching means for attaching a protective tape to the surface of the semiconductor wafer sucked and held by the holding means;
A protective tape cutting means for cutting the protective tape attached to the surface of the semiconductor wafer by including a cutter blade and moving the cutter blade along the outer periphery of the semiconductor wafer through the protective tape;
Bending means for bending the end portion of the excess protective tape after being cut by the protective tape cutting means downward so that the non-adhesive surface and the side surface of the cutter blade are substantially opposed to each other;
A protective tape cutting device comprising: In the protective tape cutting device according to claim 5,
The said bending means is a suction means which sucks from the adhesive surface side of the excess protective tape end part after cutting. The protective tape cutting device characterized by the above-mentioned. In the protective tape cutting device according to claim 5,
The said bending means is a pressing member which presses and bends the non-adhesive surface of the excess protection tape edge part after a cutting | disconnection. The protective tape cutting device characterized by the above-mentioned. In the protective tape cutting device according to claim 7,
The said pressing member is a roller which rolls in the moving direction of the said cutter blade, The said roller was arrange | positioned to the side surface or the back of the cutter blade. The protective tape cutting device characterized by the above-mentioned. In the protective tape cutting device according to claim 7,
The said press member is a bending member which has an inclined surface extended diagonally outward back from the said cutter blade front end side. The protective tape cutting device characterized by the above-mentioned.

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