JP6270642B2 - Tape expansion unit - Google Patents

Description

  The present invention relates to a tape expansion device for expanding an expanded tape or the like.

  A wafer having a plurality of devices formed on the surface is cut or laser-processed along a planned division line (street) and divided into a plurality of device chips corresponding to each device. In order to overlap and fix this device chip with another device chip or the like, a fixing adhesive layer may be provided on the back side of the device chip.

  By adhering the adhesive layer provided on the back side to an object to be fixed and applying an external stimulus such as heat or light, the adhesive layer can be cured to fix the device chip. As the adhesive layer, for example, a film-like adhesive for die bonding called a die attach film (DAF: Die Attach Film) is used.

  This film adhesive is formed in a size that covers the entire back surface of the wafer, and is adhered to the back surface of the wafer before division. A device chip having an adhesive layer on the back surface side can be formed by sticking a film adhesive on the back surface of the wafer and then cutting the film adhesive together with the wafer.

  By the way, when adopting a processing method such as DBG (Dicing Before Grinding) that does not fully cut the wafer, or SDBG (Stealth Dicing Before Grinding) that forms a modified layer by multi-photon absorption by condensing a laser beam inside the wafer, There is no process of dividing the film adhesive with the wafer.

  Therefore, a film adhesive breaking method has been proposed in which a film adhesive is attached to an expanded tape and the expanded tape is expanded after sufficiently cooling (for example, see Patent Document 1). In this breaking method, since the stretchability of the film adhesive is lowered by cooling, the film adhesive can be easily broken only by expanding the expanded tape.

  Cover member that covers the film adhesive from the top in order to prevent breakage of the film adhesive outside the wafer from adhering to the device (especially the electrode part) of the wafer when the film adhesive is expanded Is also disposed in the tape expansion device (see, for example, Patent Document 2).

JP 2007-27250 A JP 2009-272502 A

  When the film adhesive is strongly pressed by the cover member, the film adhesive sticks to the cover member. Therefore, the cover member is pressed against the film adhesive only by its own weight. Therefore, when the expanding tape is pushed up by the push-up means, the cover member jumps up with the momentum of the push-up means colliding, and there is a problem that it is not possible to suppress the scattering of the broken pieces of the film adhesive.

  The present invention has been made in view of the above points, and an object of the present invention is to apply a tape expansion device that can suppress the cover member from jumping up due to the impinging force of the push-up means.

  According to the present invention, a film-like adhesive attached to the back surface of a wafer having a plurality of division lines formed on the front surface or a wafer divided into individual chips along the division lines is formed on the opening of the annular frame. A tape expansion device that breaks along the scheduled dividing line in a state of being attached to an attached expanded tape, the frame holding means for holding the annular frame, and the annular frame held by the frame holding means A push-up means for breaking up the film adhesive by pushing up the expanded tape mounted on the sheet, a cold air supply means for supplying cold air to the space to be broken, and a portion of the film adhesive protruding from the wafer. A cover member for preventing the film-like adhesive from scattering when it is broken, and the cover member is attached to the cover member, and the cover member is A movement suppressing member that suppresses separation from the adhesive, and the cover member contacts the film adhesive and presses the film adhesive with its own weight. There is provided a tape expansion device having a surface extending to intersect with the pushing direction of the pushing means, and suppressing the movement of the cover member by air resistance.

  Preferably, the portion of the cover member that comes into contact with the film adhesive is formed of a conductive member and is grounded, whereby adhesion of the film adhesive due to static electricity is suppressed.

  According to the tape expansion device of the present invention, since the movement suppressing member is mounted on the cover member, it is possible to suppress the cover member from being flipped up when being pushed up by the pushing-up means due to the air resistance generated by the movement suppressing member.

  Since the air resistance is set as the pressing force, it can be pressed with a stronger force when the push-up means rises quickly, and when the rising speed is slow, the air resistance is reduced, so that the pressing force can be kept at an appropriate level. Effect of being adjusted automatically.

FIG. 3 is a perspective view of a wafer unit in which a back surface of a wafer divided into individual chips is attached to an expanded tape attached to an opening of an annular frame via a film adhesive. It is a disassembled perspective view of the tape expansion apparatus which concerns on this invention embodiment. It is sectional drawing of the tape sticking apparatus which concerns on embodiment of the state in which the wafer unit was set to the predetermined position. It is sectional drawing of the tape expansion apparatus after expansion tape expansion. It is a perspective view of the movement suppression member which can adjust opening area.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Referring to FIG. 1, a perspective view of the wafer unit 23 is shown. The wafer unit 23 is composed of an annular frame F, an expanded tape T attached to (attached to) the annular frame F so as to close the opening of the annular frame F, and a film adhesive attached to the expanded tape T. It includes a certain DAF 21 and a semiconductor wafer (hereinafter sometimes simply referred to as a wafer) 11 having a back surface attached to the DAF 21.

  A wafer 11 shown in FIG. 1 has devices 15 such as ICs and LSIs formed in a region defined by a plurality of division lines 13 formed in a grid pattern, and grooves such as cutting grooves are formed along the division lines 13. 17 is a wafer in which the wafer 11 is divided into individual device chips 19.

  The wafer 11 divided into the individual device chips 19 in this manner is manufactured by, for example, a predicing method (Dicing Before Grinding) or the like. In the first dicing method, a cutting groove having a depth equal to or larger than the finished thickness of the device is formed along the division line 13 from the front surface 11a side of the wafer 11, and then a protective tape is attached to the front surface 11a, and then the back surface of the wafer 11 is formed. The wafer 11 is divided into individual device chips 19 by grinding 11b to expose the cutting grooves on the surface 11a.

  The DAF 21 is attached to the back surface of the wafer 11 divided into individual device chips 19 by the pre-dicing method, and the DAF 21 is attached to the expanded tape T having the outer peripheral portion attached to the annular frame F. From the front surface 11a of the wafer 11 By peeling off the surface protection tape, the wafer unit 23 shown in FIG. 1 is manufactured.

  It should be noted that the wafer to which the tape expansion apparatus of the present invention is applied is not only a wafer divided into individual device chips 19 as shown in FIG. A form in which DAF 21 is attached to the back surface of the wafer before division in which a quality layer is formed may be used.

  Referring to FIG. 2, an exploded perspective view of the tape sticking device 2 according to the embodiment of the present invention is shown. The tape sticking device 2 is accommodated in the housing 4 shown in FIGS. 3 and 4, but the housing 4 is omitted in the exploded perspective view of FIG. 2.

  The housing 4 is formed with an opening for taking the wafer unit 23 into and out of the processing space 5, and a shutter for opening and closing the opening is mounted, but these are omitted in FIGS. .

  A table 6 having a circular opening 8 on an upper surface (support surface) 6 a is placed in the housing 4. An expansion drum 10 is disposed in the circular opening 8 of the table 6 so as to be movable up and down. A plurality of rollers 12 are attached to the outer periphery of the upper end portion of the expansion drum 10. The table 6 is made of a metal such as SUS.

  Reference numeral 14 denotes a moving mechanism (moving means) that moves the expansion drum 10 in the vertical direction, and includes a ball screw 16 and a servo motor 18 connected to one end of the ball screw 16. A U-shaped bracket 25 is fixed to the bottom of the expansion drum 10, and a nut 27 that is screwed into the ball screw 16 is disposed on the U-shaped bracket 25. When the servo motor 18 is driven, the ball screw 16 rotates, and the expansion drum 10 moves in the vertical direction according to the rotation direction of the ball screw 16.

  Reference numeral 20 denotes a pressing plate, which has a circular opening 22 corresponding to the circular opening 8 of the table 6 and has three pins 24 erected on the upper surface 20a thereof at a distance of 120 ° in the circumferential direction.

  The pressing plate 20 is moved by a moving means (not shown) between a fixed position where the annular frame F of the wafer unit 23 is pressed in cooperation with the upper surface 6a of the table 6 and a retracted position raised from the fixed position. The holding plate 20 is made of a metal such as SUS.

  Reference numeral 26 denotes a cover member, which has a circular opening 28 having a diameter smaller than that of the circular opening 22 of the presser plate 20 at the center, and its cross section is formed in a stepped shape, as is apparent from FIGS. 3 and 4. .

  The step portion of the cover member 26 is formed with three insertion holes 30 that are 120 ° apart from each other in the circumferential direction through which the pins 24 of the holding plate 20 are inserted, and the upper surface thereof is mutually circumferential. Three screw holes 32 separated by 120 ° are formed. The cover member 26 is made of a metal such as SUS. The cover member 26 formed of a conductive member is grounded.

  Reference numeral 34 denotes a movement restraining member, which has a circular opening 36 at the center, three insertion holes 38 that are 120 ° apart from each other in the circumferential direction through which the pins 24 are inserted, and a circumference into which screws are inserted. It has three insertion holes 40 that are 120 ° apart from each other in the direction. The movement restraining member 34 is made of a light and moderately strong resin such as PET (polyethylene terephthalate) or polycarbonate.

  The movement suppressing member 34 is placed on the cover member 26, and the pin 24 of the pressing plate 20 is inserted into the insertion hole 30 of the cover member 26 and the insertion hole 38 of the movement suppressing member 34 to assemble the tape expansion device 2. When the tape sticking device 2 is assembled in this manner, the lower surface of the stepped portion of the cover member 26 comes into contact with the upper surface of the pressing plate 20 as shown in FIG.

  Hereinafter, an operation of the tape expansion device 2 configured as described above will be described. First, the wafer unit 23 shown in FIG. 1 is carried into the processing space 5 through an opening (not shown) of the housing 4, and the annular frame F of the wafer unit 23 is placed on the upper surface 6 a of the table 6.

  Next, the holding plate 20 that has been raised to the retracted position is moved downward to a fixing position by a moving means (not shown), and the annular frame F is sandwiched and fixed between the upper surface 6 a of the table 6 and the lower surface of the holding plate 20. The holding plate 20 is locked at a fixed position by a locking means (not shown).

  In a state where the holding plate 20 is moved to the fixed position and locked, the contact portion 26a which is the bottom surface of the cover plate 26 contacts the DAF 21 attached to the expanding tape T. The contact portion 26a of the cover member 26 is formed in a concavo-convex shape and is subjected to a plating process that is difficult to adhere to the DAF 21.

  In this embodiment, the extension drum 10 and the moving mechanism 14 that moves the extension drum in the vertical direction constitute a push-up means. With the wafer unit 23 set in the initial position as described above, the expansion drum 10 is retracted with the roller 12 mounted on the outer peripheral portion of the expansion drum 10 being separated from the expanding tape T and the roller 12 being accommodated in the opening 8 of the table 6. Is positioned.

  In this state, the cool air supply means 42 is operated to supply cool air into the processing space 5 surrounded by the housing 4, and the processing space 5 is cooled to, for example, 0 ° C. or less. With the processing space 5 thus cooled, the servomotor 18 is driven to rotate the ball screw 16 as shown in FIG. 4, and the expansion drum 10 is pushed upward.

  Since the outer peripheral portion of the expanded tape T is attached to the annular frame F, and the annular frame F is fixed by the table 6 and the holding plate 20, the expanded tape T is mainly radially expanded in accordance with the push-up of the expansion drum 10. The external force in the radial direction acts on the DAF 21.

  As a result, the DAF 21 attached to the back surface 11b of the wafer 11 is divided according to each device chip 19, and the device chip 19 having the DAF 21 attached to the back surface can be obtained.

  Since the expansion drum 10 is pushed up with a considerable momentum, the cover member 26 in which the contact portion 26a is in contact with the DAF 21 outside the wafer 11 due to its own weight jumps up, but the movement suppressing member 34 having the opening 36 has the cover member 26. Therefore, air resistance is generated along with the movement of the movement suppressing member 34, and the upward force of the cover member 26 is suppressed by this resistance force, so that the contact portion 26 a of the cover member 26 becomes the DAF 21 on the outer peripheral portion of the wafer 11. Since it is maintained with pressing from above, scattering of broken pieces of DAF 21 can be suppressed.

  Since the air resistance that accompanies the movement of the movement restraining member 34 is used as the pressing force of the cover member 26, the expansion drum 10 is pressed with a stronger force when the rising is fast, and the air resistance is also reduced when the rising is slow, so that the appropriate pressing force is obtained. It is automatically adjusted to the pressing force suitable for the conditions.

  You may make it adjust the opening area of the movement suppression member 34 for adjustment of air resistance. For example, as shown in FIG. 5, an adjustment member 46 having an opening 48 having a diameter smaller than the diameter of the opening 36 of the movement suppressing member 34 is inserted into the insertion hole 50, and the screw hole 44 of the movement suppressing member 34 is inserted. By fastening, the adjustment member 46 is fixed to the movement suppressing member 34, and the opening area of the movement suppressing member 34 can be adjusted.

  As described above, since the cover member 26 is made of a metal such as SUS and is further grounded, it is possible to prevent the broken pieces of the DAF 21 due to static electricity from adhering to the cover member 26.

  In the above-described embodiment, the table 6 is fixed and the pressing plate 20 is movable. However, the pressing plate 20 is fixed at a predetermined position, and the table 6 is moved in the vertical direction by a moving means such as an air cylinder. You may do it.

2 Tape sticking device 4 Housing 5 Processing space 6 Table 10 Expansion drum 11 Semiconductor wafer 12 Roller 14 Moving mechanism 16 Ball screw 17 Groove 18 Servo motor 19 Device chip 20 Holding plate 21 DAF
23 Wafer unit 24 Pin 26 Cover member 34 Movement restraining member

Claims (2)

Expanded tape with a film adhesive attached to the back of a wafer having a plurality of division lines formed on the front surface or a wafer divided into individual chips along the division lines. A tape expansion device that breaks along the scheduled dividing line,
Frame holding means for holding the annular frame;
Push-up means for pushing up the expanded tape attached to the annular frame held by the frame holding means to break the film adhesive;
Cold air supply means for supplying cold air to the space to be broken;
A cover member that suppresses scattering of the film adhesive when the portion of the film adhesive protruding from the wafer breaks;
A movement restraining member mounted on the cover member and restraining the cover member from separating from the film adhesive,
The cover member contacts the film adhesive and presses the film adhesive under its own weight,
The tape expansion device, wherein the movement restraining member has a surface extending to intersect with the pushing-up direction of the pushing-up means, and suppresses the movement of the cover member by air resistance.   2. The tape expansion device according to claim 1, wherein a portion of the cover member that comes into contact with the film adhesive is formed of a conductive member and grounded, and adhesion of the film adhesive due to static electricity is suppressed. .