JP7030469B2 - Tape expansion device and tape expansion method - Google Patents

Description

The present invention relates to a tape expansion device and a tape expansion method used when a plate-shaped workpiece such as a semiconductor wafer to which an adhesive film (DAF: Die Attach Film) is attached is divided into a large number of semiconductor chips and the like.

In the semiconductor device manufacturing process, a dividing device for dividing a plate-shaped workpiece such as a semiconductor wafer is used. As this type of dividing device, a modified layer along the planned division line is continuously formed inside the workpiece by laser processing, and the modified layer whose strength is reduced by applying an external force is used as a starting point. Those that divide a work piece are known (see, for example, Patent Document 1).

As a means for applying an external force when dividing a work piece, a tape expansion device for expanding an expanded tape attached to the back surface of the work piece is known. The expansion of the expanded tape applies a force in the expansion direction to the work piece, and the work piece is broken along the planned division line. In this type of expansion device, the expansion tape is expanded and the work piece is divided while the adhesive of the expand tape is cooled and cured, and then the work piece is transferred to a heating means to heat the expanded tape loosened by the expansion. (See, for example, Patent Document 2). In particular, in the workpiece to which the DAF, which is an adhesive film for die bonding, is attached, the DAF is cured by cooling, so that the division efficiency at the time of expanding the expanded tape is remarkably improved.

Japanese Patent No. 3408805 Japanese Unexamined Patent Publication No. 2010-206136

In the expand tape expansion device and expansion method as described above, the expanded tape is transported to the heating means in a loosened state after the workpiece is divided, so that the separated device (semiconductor chip, etc.) moves during transport. There was a risk of mutual interference and edge chipping.

The present invention has been made in view of such a problem, and it is possible to realize good division in which edge chipping and the like are suppressed by a tape expansion device and a tape expansion method for expanding an expanded tape to divide a wafer. The purpose.

The present invention is a tape expansion device for expanding an expanded tape having a wafer having a plurality of devices formed on a region partitioned by a plurality of planned division lines and having an outer peripheral portion mounted on an annular frame. Then, the loading / unloading mechanism for loading the annular frame into the tape expansion device with the wafer attached to the expanding tape facing vertically downward, and the annular state with the wafer attached to the expanding tape facing vertically downward. A frame holding means for holding the frame on the upper surface, a pressing means for expanding the expanding tape by pressing the expand tape from above between the frame holding means and the outer peripheral edge of the wafer in an annular shape, and a pressing means for dividing the wafer along a split starting point, and an annular shape. A cooling table that is vertically movable on the inner peripheral side of the pressing means and has a suction hole on the contact surface that abuts over the entire surface of the wafer via the expand tape, and extends between the frame holding means and the outer peripheral edge of the wafer. It is characterized by comprising a heating means for heating and shrinking the expanded tape.

The present invention is also a tape expansion method using the above-mentioned tape expansion device, in which an annular frame is provided so that the back surface of the expanded tape is located below the contact surface of the cooling table with the wafer facing vertically downward. A holding step for holding, an expanded tape cooling step in which the back surface of the expanding tape is brought into contact with the contact surface of the cooling table after the holding step is performed, and a suction force is applied to the suction holes to cool the expanded tape, and a frame holding. The frame is held in a state where the expanding tape expansion step for expanding the expanded tape by relatively moving the means and the pressing means and the contact surface of the cooling table are brought into contact with the back surface of the expanding tape to apply suction force to the suction holes. It is characterized by having a heating step of heating and shrinking the expanded tape extended between the means and the outer peripheral edge of the wafer by the heating means.

According to the above tape expansion device and tape expansion method, the cooling table and the frame holding means can be used from the process of cooling the expanded tape with the cooling table to divide the wafer to the process of reducing the slack of the expanded tape by heating shrinkage. Prepare on a common stage. Therefore, it is not necessary to transfer the wafer in a loosened state of the expanded tape, and the movement of the device that causes edge chipping or the like can be suppressed as much as possible. Further, by sharing the stage for cooling division and the stage for heat shrinking with respect to the expanded tape, the footprint of the device can be reduced and the space efficiency can be improved.

As described above, according to the tape expansion device and the tape expansion method of the present invention, it is possible to realize good division of the wafer while suppressing edge chipping and the like.

It is sectional drawing which shows the tape expansion apparatus of this embodiment. It is sectional drawing which shows the holding step and expanded tape cooling step by a tape expansion device. It is sectional drawing which shows the expanded tape cooling step by a tape expansion device. It is sectional drawing which shows the expanded tape expansion step by a tape expansion apparatus. It is sectional drawing which shows the heating step by a tape expansion device. It is the figure which looked at the top view of the tape expansion apparatus from the position along the VI-VI line of FIG.

Hereinafter, the tape expansion device and the tape expansion method according to the present embodiment will be described with reference to the accompanying drawings. 1 to 5 show each process in the tape expansion device in order, and FIG. 6 shows a top view of a part of the components of the tape expansion device. In the following description, the vertically upward direction is referred to as upward, and the vertically downward direction is referred to as downward. The tape expansion device is not limited to this configuration, and can be appropriately changed within the scope of the gist of the invention.

The tape expansion device 20 of the present embodiment holds the annular frame 11 constituting the wafer unit 10 and expands the expanding tape 12 supported by the annular frame 11 to expand the DAF (Die) attached to the expanding tape 12. Attach Film) 17 and the wafer 13 are divided. DAF17 is an adhesive film having adhesiveness, and is laminated on the back surface side of the wafer 13. The wafer 13 is attached to the expanding tape 12 via the DAF 17. The side of the expanded tape 12 on which the wafer 13 and the DAF 17 are supported is the front surface, and the opposite side is the back surface.

The annular frame 11 is an annular body made of metal, and a circular opening 14 covered with an elastically deformable expand tape 12 is formed in the center of the annular frame 11. The outer peripheral portion of the expanding tape 12 is fixed to the back surface side of the annular frame 11, and the expanding tape 12 is attached to the DAF 17 on the back surface side of the wafer 13 in the inner region of the opening 14 that does not overlap with the annular frame 11. There is a radial gap between the outer peripheral edge of the wafer 13 and the inner peripheral edge of the annular frame 11 (the edge of the opening 14).

The wafer 13 is a semiconductor device wafer or the like. A plurality of scheduled division lines (not shown) intersecting in a grid pattern are provided on the surface of the wafer 13, and devices such as semiconductor chips are formed in each region partitioned by the scheduled division lines. Further, inside the wafer 13, a reforming layer 15 (see FIGS. 1 to 3), which is a division starting point, is formed along a planned division line. The modified layer 15 is a region where the density, refractive index, mechanical strength and other physical properties inside the wafer 13 are different from those of the surroundings due to the irradiation of the laser, and the strength is lower than that of the surroundings. In this embodiment, the reforming layer 15 is exemplified as a split starting point, but the split starting point may be a starting point at the time of splitting by reducing the strength of the wafer 13, for example, a laser machined groove, a cutting groove, and a scribe line. But it may be.

As shown in FIGS. 1 to 5, the tape expansion device 20 includes a base 21, a frame holding means 22, a pressing means 23, a cooling table 24, a temporary placement stage 25, a frame gripping claw 26, and heating. Means 27 and. The base 21 is a non-movable part that supports each part of the tape expansion device 20, and the upper base portion 21A and the lower base portion 21B shown in FIGS. 1 to 5 form a part of the entire base 21. Is.

The frame holding means 22 has an annular shape including an upper surface 30 capable of holding the annular frame 11 of the wafer unit 10 from below, and an opening 31 having a size corresponding to the opening 14 of the annular frame 11. .. The frame holding means 22 is supported so as to be vertically movable via the elevating drive mechanism 32. The elevating drive mechanism 32 is supported by the lower base portion 21B, and the frame holding means 22 is supported by the tip of the support rod 33 extending upward. The frame holding means 22 can be raised and lowered by changing the amount of protrusion of the support rod 33 by driving a motor or an actuator built in the raising and lowering drive mechanism 32.

The pressing means 23 has an annular shape having a larger diameter than the wafer 13 and a smaller diameter than the inner peripheral edge of the opening 14 of the annular frame 11, and is supported by the upper base portion 21A with its tip facing downward. .. The pressing means 23 is fixed to the upper base portion 21A and does not move in the vertical direction. A plurality of rollers 35 are provided on the lower surface (tip) of the pressing means 23 so as to be rollable over the entire circumference.

The cooling table 24 is located on the inner peripheral side of the annular pressing means 23, and is configured by overlapping the upper support 36 located on the upper side and the lower support 37 located on the lower side. A part of the cooling table 24 is shown in an enlarged manner in FIG. An annular protrusion 36a, which is an annular protrusion that projects downward, is formed on the lower surface of the upper support 36. A circular recess 36b is formed on the inner peripheral side of the annular protrusion 36a. The upper support 36 and the lower support 37 are combined in a state where the annular protrusion 36a is in contact with the upper surface of the lower support 37. In the radial central portion where the recess 36b is present, the upper support 36 and the lower support 37 are separated from each other to form a gap.

A plate-shaped mesh material 38 is provided on the lower surface side of the lower support 37 in the cooling table 24. The diameter of the plate-shaped mesh material 38 is substantially the same as the diameter of the wafer 13, and a plurality of fine suction holes 38a (see the enlarged portion of the cooling table 24 in FIG. 1) are formed in the entire plate-shaped mesh material 38. There is. Further, on the lower surface of the lower support 37, an annular suction groove 39 is formed in a region on the outer peripheral side of the plate-shaped mesh material 38.

The upper support 36, the lower support 37, and the plate-shaped mesh material 38 constituting the cooling table 24 are each made of a metal having excellent thermal conductivity. The upper support 36 and the lower support 37 in the present embodiment are made of aluminum, and the plate-shaped mesh material 38 is made of stainless steel. The material of each part constituting the cooling table 24 is not limited to this.

A suction means 40 and a suction means 41 for applying a suction force are provided on the lower surface (contact surface) side of the cooling table 24. The suction means 40 has a suction path extending from the suction source 40a to the plate-shaped mesh material 38, and is provided with a control valve 40b in the middle of the suction path. When the suction source 40a is driven to bring the control valve 40b into a communicating state, a suction force acts on a plurality of suction holes 38a of the plate-shaped mesh material 38. When the control valve 40b is in a non-communication state, the suction force does not act on the suction holes 38a of the plate-shaped mesh material 38. The suction means 41 has a suction path extending from the suction source 41a to the suction groove 39, and is provided with a control valve 41b in the middle of the suction path. When the suction source 41a is driven to bring the control valve 41b into a communicating state, a suction force acts on the suction groove 39. When the control valve 41b is in a non-communication state, the suction force does not act on the suction groove 39. That is, in the cooling table 24, the suction force can be individually turned on and off for the plate-shaped mesh material 38 and the suction groove 39.

The cooling table 24 is cooled by the cooling means 42. The cooling means 42 has a cooling transmission unit 43 connected to the center of the upper surface of the upper support 36, and the cooling transmission unit 43 can be brought into a cooling (low temperature) state by a cooling source (not shown). Any cooling source may be used in the cooling means 42. For example, as the cooling method, a type using a compressor, a type using a Pelche element, or the like can be appropriately selected. Further, the position where the cooling source is provided may be the upper part of the cooling transmission unit 43 or may be a position away from the cooling transmission unit 43. When the cooling source is arranged at a position away from the cooling transmission unit 43, cold air can be guided from the cooling source to the cooling transmission unit 43 through a pipeline.

When the cooling transmission unit 43 is cooled by the cooling means 42, the cooling state propagates radially from the vicinity of the center of the upper support 36 to which the cooling transmission unit 43 is connected toward the outer periphery of the upper support 36, and the upper support The cooling state propagates to the lower support 37 through the annular protrusion 36a located near the outer periphery of the 36. In the lower support 37, contrary to the upper support 36, the cooling state propagates from the outer peripheral side in contact with the annular protrusion 36a toward the center. Therefore, in the cooling table 24, substantially the entire radial direction can be cooled evenly. As the lower support 37 is cooled, the plate-shaped mesh material 38 provided on the lower surface of the lower support 37 is also cooled. Since the upper support 36, the lower support 37, and the plate-shaped mesh material 38 are each made of a metal having excellent thermal conductivity, they can be cooled quickly and efficiently.

The cooling table 24 is supported so as to be able to move up and down in the vertical direction via the lifting drive mechanism 50. The elevating drive mechanism 50 is supported on the lower surface side of the upper base portion 21A, and the cooling table 24 is supported by the tip of the support rod 51 extending downward. The cooling table 24 can be moved up and down by changing the amount of protrusion of the support rod 51 by driving a motor or actuator built in the lifting drive mechanism 50. When the cooling table 24 is moved upward, as shown in FIG. 4, the cooling table 24 is pulled inside the annular pressing means 23, and the lower surface of the plate-shaped mesh material 38 is moved from the tip (lower end) of the roller 35. Can also be located above. The cooling transmission unit 43 of the cooling means 42 moves up and down together with the cooling table 24.

A pair of temporary placement stages 25 are provided at positions between the upper base portion 21A and the lower base portion 21B in the vertical direction. As shown in FIG. 6, each temporary placement stage 25 has an elongated shape extending in the horizontal direction, and is arranged substantially parallel to each other. The pair of temporary placement stages 25 can be moved in the horizontal direction and the vertical direction by the stage drive mechanism 55, respectively. Although the stage drive mechanism 55 is schematically shown in the drawing, the stage drive mechanism 55 includes an actuator for driving in the horizontal direction, an actuator for driving in the vertical direction, and the like. The interval between the pair of temporary placement stages 25 is changed by the horizontal movement, and the annular frame 11 of the wafer unit 10 can be supported on the pair of temporary placement stages 25 at the close positions shown in FIGS. 1 and 6. .. Each temporary placement stage 25 has two upper and lower support steps that can support the outer edge of the annular frame 11. Each support step portion has support surfaces 25a and 25b that support the annular frame 11 from below, and wall portions 25c extending in the vertical direction are formed on the sides of the support surfaces 25a and 25b. By sandwiching the annular frame 11 between the wall portions 25c of the pair of temporary placement stages 25, the horizontal position of the wafer unit 10 can be determined. As shown in FIG. 6, the frame holding means 22 has a shape that allows it to move up and down without interfering with a pair of temporary placement stages 25 located at close positions.

The wafer unit 10 is carried in and out of the tape expansion device 20 and the wafer unit 10 is carried out from the tape expansion device 20 by using an carry-in / out mechanism (not shown). At the time of loading and unloading, the wafer unit 10 is delivered between the loading / unloading mechanism and the temporary placement stage 25.

A plurality of frame gripping claws 26 are provided at different positions in the circumferential direction. The individual frame gripping claws 26 are rotatably supported with respect to the base 21, and the gripping release position (one-dot chain line in FIGS. 1, 2, 4, 5, and 6) and the gripping position are rotatably supported by the rotation. It can operate according to (solid line in FIGS. 3 and 6). The frame gripping claw 26 is not involved in holding the wafer unit 10 at the gripping release position, and can hold the vicinity of the outer edge of the annular frame 11 from below at the gripping position. As shown in FIG. 6, in the region where the frame gripping claw 26 exists in the circumferential direction, the annular frame holding means 22 has a partially cutout shape, and the frame holding means 22 has a frame. It can be raised and lowered without interfering with the gripping claw 26.

The heating means 27 is a hot air heater that supplies heat to the expanding tape 12 by blowing hot hot air from the upper end portion. A plurality of heating means 27 are arranged at different positions in the circumferential direction. Each heating means 27 is located on the inner diameter side of the frame holding means 22 and on the outer diameter side of the cooling table 24 in the radial direction, and is located below the pressing means 23 and the cooling table 24 in the vertical direction. ing. Each heating means 27 is supported so as to be able to move up and down in the vertical direction via an elevating drive mechanism 56. The elevating drive mechanism 56 is supported by the lower base portion 21B, and the heating means 27 is supported by the tip of the support rod 57 extending upward. The heating means 27 can be moved up and down by changing the amount of protrusion of the support rod 57 by driving a motor or actuator built in the lifting drive mechanism 56.

The process of dividing the wafer 13 by the tape expansion device 20 having the above configuration will be described. First, the reforming layer 15 as a split starting point is formed on the wafer 13 in advance by laser processing or the like, and then the wafer unit 10 is conveyed to the tape expansion device 20 by using an loading / unloading mechanism (not shown). At this time, as shown in FIG. 1, in the wafer unit 10, the wafer 13 attached to the expand tape 12 via the DAF 17 is placed vertically downward, and the wafer unit 10 is located on the lower side of the pair of temporary placement stages 25 at close positions. The annular frame 11 is supported by the support step portion (support surface 25a) of the above. The outer edge portion of the annular frame 11 is sandwiched between the wall portions 25c of the pair of temporary placement stages 25, and the position of the wafer unit 10 is determined. More specifically, as shown in FIG. 1, an annular region (expand tape 12 is attached to the annular frame 11 and any of the wafer 13 and DAF 17) between the opening 14 of the annular frame 11 and the outer edge of the wafer 13. The non-existing region) is located below the annular pressing means 23. Further, the upper surface 30 of the frame holding means 22 is located below the annular frame 11, and the heating means 27 is located below the exposed portion of the expanding tape 12 between the annular frame 11 and the wafer 13. The frame holding means 22 and the heating means 27 are held in standby positions separated downward from the wafer unit 10, respectively. The cooling table 24 is positioned so that the lower surface of the plate-shaped mesh material 38 is positioned in the vertical direction substantially the same as the tip of the roller 35.

Subsequently, a holding step is carried out. As shown in FIG. 2, in the holding step, the elevating drive mechanism 32 is driven to move the frame holding means 22 upward from the lower standby position shown in FIG. Since the frame holding means 22 has a shape that does not overlap with the pair of temporary placing stages 25 in the close position (see FIG. 6), the frame holding means 22 may rise without being hindered by the temporary placing stage 25. can. Then, the upper surface 30 of the frame holding means 22 comes into contact with the lower surface of the annular frame 11, and the frame holding means 22 pushes up the wafer unit 10 upward. At the stage where the annular frame 11 is pushed up by the frame holding means 22, the stage drive mechanism 55 is driven to separate the pair of temporary placement stages 25 in the horizontal direction (see FIG. 2). The frame holding means 22 is raised to a position where the back surface of the expanding tape 12 abuts on the lower surface of the cooling table 24. When the frame holding means 22 rises to the position, the frame gripping claw 26 is rotated from the gripping release position to the gripping position. As a result, the frame gripping claw 26 is in a state of holding the annular frame 11 from below (see FIG. 3). After the holding of the annular frame 11 is handed over to the frame gripping claw 26, the elevating drive mechanism 32 is driven to move the frame holding means 22 downward by a predetermined amount (see FIG. 3).

The expanding tape cooling step is carried out in a state where the back surface of the expanding tape 12 is in contact with the lower surface of the cooling table 24 (FIGS. 2 and 3). In the expanding tape cooling step, the cooling means 42 cools the cooling table 24 while the suction means 40 and the suction means 41 are in the suction state respectively. Specifically, by driving the suction sources 40a and 41a to bring the control valves 40b and 41b into a communicating state, the suction force by the suction means 40 acts on the suction holes 38a of the plate-shaped mesh material 38, and the suction means 41 Acts on the suction groove 39. The plate-shaped mesh material 38 constituting the lower surface of the cooling table 24 has substantially the same diameter as the wafer 13, and the entire lower surface of the plate-shaped mesh material 38 is the back surface side of the expanding tape 12 to the wafer 13 and the DAF 17. Contact with. In other words, the lower surface of the plate-shaped mesh material 38 comes into contact with the entire surface of the wafer 13 and the DAF 17 via the expand tape 12. The suction groove 39 faces the back surface of the expanded tape 12 in the peripheral region of the wafer 13 and the DAF 17. Then, the back surface of the expand tape 12 is suction-held on the lower surface of the cooling table 24 by the suction force of the suction means 40 and the suction means 41 acting on the suction holes 38a and the suction groove 39 of the plate-shaped mesh material 38, respectively.

The expanding tape 12, the wafer 13, and the DAF 17 of the wafer unit 10 are cooled by being adsorbed and held on the lower surface of the cooling table 24 in the cooled state. As described above, the cooling table 24 has a configuration in which the cooling table 24 is uniformly cooled over substantially the entire radial direction. Further, by exerting a suction force on the suction holes 38a of the plate-shaped mesh material 38 provided on the lower surface of the cooling table 24 and the suction groove 39, the expand tape 12 adheres to substantially the entire lower surface of the cooling table 24. As a result, the expanded tape 12, the wafer 13, and the DAF 17 can be efficiently cooled without bias. By cooling, the physical properties such as the elasticity of the wafer 13 and the DAF 17 to be divided change, and the adhesive and the DAF 17 of the expanding tape 12 are cured. It becomes easy to divide the DAF17. The cooling state (temperature) of the cooling table 24 is set in advance so as to obtain the optimum division efficiency according to the material and type of the expanded tape 12, the wafer 13, and the DAF 17.

As shown in FIGS. 2 and 3, in the expanding tape cooling step, the lower surface of the cooling table 24 and the lower ends of the plurality of rollers 35 provided on the pressing means 23 are at substantially the same height position, and each roller 35 is expanded. It is in a state of being lightly in contact with the back surface of the tape 12 (the region between the inner edge portion of the opening 14 of the annular frame 11 and the outer edge portion of the wafer 13). Further, the frame gripping claw 26 holds the annular frame 11 at the same height position as the wafer 13. Therefore, the entire area of the expanded tape 12 from the central portion attached to the wafer 13 to the outer peripheral portion attached to the annular frame 11 is kept flat, and no external force for expanding the expanded tape 12 acts.

After the expanding tape 12, the wafer 13, and the DAF 17 have been sufficiently cooled, the expanding tape expansion step (FIG. 4) is performed. As shown in FIG. 4, in the expanding tape expansion step, the control valve 40b and the control valve 41b are brought into a non-communication state, respectively, and the suction by the suction means 40 and the suction means 41 is released. Further, the elevating drive mechanism 50 is driven to move the cooling table 24 upward so as to be separated from the back surface of the expand tape 12. As a result, the expanded tape 12 can be reliably expanded in a state where the adsorption to the cooling table 24 is released.

As another form, the suction means 40 and the suction means 41 are configured to be capable of ejecting air in addition to suction, respectively, and the suction holes 38a are not moved upward as shown in FIG. It is also possible to carry out the expanding tape expansion step while ejecting air from the suction groove 39. It is possible to prevent the expanding tape 12 from adhering to the cooling table 24 due to the ejection of air.

Then, the elevating drive mechanism 32 is driven to move the frame holding means 22 upward from the position shown in FIG. 3 at high speed. When the frame holding means 22 rises by a predetermined amount, the upper surface 30 comes into contact with the annular frame 11 from below, and a force is transmitted from the frame holding means 22 to the annular frame 11. By starting the ascent of the frame holding means 22 from a position (FIG. 3) downwardly separated from the annular frame 11 held by the frame gripping claw 26, the ring-shaped frame 11 is pushed up from the frame holding means 22 at high speed. It can be done vigorously with. As described above, since the frame holding means 22 has a shape that does not interfere with the frame gripping claw 26, the frame is held while the annular frame 11 is held by the frame gripping claw 26 as shown in FIG. The upper surface 30 of the means 22 can be brought into contact with the annular frame 11. When the annular frame 11 is pushed up by the frame holding means 22, the frame gripping claw 26 is rotated from the gripping position to the gripping release position.

As shown in FIG. 4, when the frame holding means 22 with the upper surface 30 in contact with the annular frame 11 moves further upward, the annular frame 11 is pushed up, whereas the annular frame 11 of the expanded tape 12 is pushed up. The region located inside the ring is pressed against the roller 35 of the annular pressing means 23 to limit its upward movement (the pressing force 23 receives the pressing force in an annular shape). Due to the relative movement of the frame holding means 22 and the pressing means 23, the bonding regions of the DAF 17 and the wafer 13 in the expanding tape 12 are pulled and expanded (extended) in the radial direction. Then, an external force acts on the wafer 13 and the DAF 17 in the diameter-expanding direction, and cracks occur in the thickness direction of the wafer 13 and the DAF 17 starting from the modified layer 15 (FIGS. 1 to 3) formed in the wafer 13. Occurs. By applying an external force until the crack penetrates from the front surface of the wafer 13 to the back surface of the DAF 17 (the surface attached to the expanding tape 12), the chip 16 and the DAF 17 are divided along the planned division line (see FIG. 4). ). As described above, the division efficiency of the wafer 13 and the DAF 17 is improved by cooling, and it is possible to perform reliable division along the planned division line. In particular, curing DAF17, which is difficult to divide at room temperature, by cooling is extremely effective in improving the division efficiency.

When the wafer 13 is divided, split debris is generated from the broken portion along the planned division line. Since the wafer 13 and the DAF 17 are installed vertically downward, the split debris naturally falls downward, and it is possible to prevent the split debris from adhering to the surface of the chip 16 (FIG. 4) after division and the expanded tape 12. The fallen split waste is collected by a collection means (not shown).

When the division of the wafer 13 and the DAF 17 is completed, the lower surface of the cooling table 24 is the lower end position of the plurality of rollers 35 of the pressing means 23 for the cooling table 24 which has been pulled up in the previous expanded tape expansion step (see FIG. 4). Lower to a height position that roughly matches. Then, the lower surface of the lower support 37 and the plate-shaped mesh material 38 abuts on the back surface of the expand tape 12. In this state, the control valve 40b and the control valve 41b are switched to a communicating state, and suction force is applied to the suction holes 38a and the suction groove 39 by the suction means 40 and the suction means 41 to form the lower support 37 and the plate-shaped mesh material 38. The expand tape 12 is brought into close contact with the lower surface. By the expanding tape 12 being brought into close contact with the cooling table 24 side, the divided chips 16 and DAF 17 are maintained in a separated state. At this stage, the cooling table 24 is not cooled by the cooling means 42, and the cooling table 24 is used only for adsorbing the expanded tape 12.

Subsequently, the elevating drive mechanism 32 is driven to lower the frame holding means 22 to release the external force applied to the expanding tape 12 in the expansion direction. As shown in FIG. 5, the expanded tape 12 is slackened after being stretched in the expanded tape expansion step. The slack of the expanded tape 12 is formed on the outside of the region in close contact with the cooling table 24 by the suction force from the suction hole 38a and the suction groove 39, that is, the region on the outer edge side of the divided chips 16 and DAF 17, and the annular frame. It appears as a shape that hangs downward due to its own weight with respect to 11.

Subsequently, a heating step (see FIG. 5) is performed in which the expanded tape 12 stretched in the expanded tape expansion step is heated and shrunk. The heating means 27 is located below the slack portion of the expanding tape 12, and when heating, the elevating drive mechanism 56 is driven to raise the heating means 27 and bring it closer to the expanding tape 12. Then, with an appropriate distance from the expanding tape 12 as shown in FIG. 5, hot air at a high temperature (for example, 100 ° C. or higher) is blown from the heating means 27 toward the slack portion of the expanding tape 12. The expanded tape 12 heated by this warm air shrinks heat and the slack is reduced.

At this time, since the suction force acts on substantially the entire lower surface of the cooling table 24, the expand tape 12 does not hang downward at least in the region on the inner diameter side of the portion where the suction groove 39 is provided. It is in close contact with the cooling table 24 side. Therefore, the hanging of the expand tape 12, which is the target of heat shrinkage, can be reliably positioned in the region where the heating means 27 can efficiently heat (the region on the outer diameter side of the wafer 13). Further, since the central portion of the expanded tape 12 to which the divided chips 16 and DAF 17 are attached is in close contact with the cooling table 24 and is not easily affected by heat shrinkage due to heating, the chips 16 do not interfere with each other during heating. It is possible to prevent regular interference and the like.

If the expanding tape 12 has a large amount of slack, heating may be performed stepwise while changing the suction area for the expanding tape 12. Specifically, first, the first stage heating is performed by the heating means 27 in a state where the suction force is applied to both the suction hole 38a and the suction groove 39. Subsequently, when the suction to the suction groove 39 by the suction means 41 is released, the slack of the expand tape 12 that could not be completely removed by the heating of the first stage is reduced due to the decrease of the suction region of the expand tape 12 by the cooling table 24. The rest appears as a downward hang. The portion of the expanded tape 12 is heated in the second stage by the heating means 27. By heating the expanding tape 12 step by step in this way, the expanding tape 12 can be efficiently and surely heat-shrinked even when the expanding tape 12 has a large amount of slack.

The heating means 27 may be provided with a nozzle that diffuses the range of the warm air blown upward. Further, the heating means 27 may be provided with a variable direction nozzle capable of changing the blowing direction of warm air. With these configurations, the optimum heating range by the heating means 27 can be appropriately set.

Further, in the present embodiment, the expanded tape 12 is heated in a wide range in the circumferential direction by providing the plurality of heating means 27 at different positions in the circumferential direction. As a modification, the base 21 may be supported by the heating means 27 so that it can move not only up and down but also in the circumferential direction. This facilitates heating of the expanding tape 12 over the entire annular region corresponding to the annular pressing means 23.

After the heating step is completed, the wafer unit 10 is carried out from the tape expansion device 20 to the outside. At the time of carrying out, the suction from the suction hole 38a and the suction groove 39 of the cooling table 24 to the expanding tape 12 is released. Then, the pair of temporary placement stages 25 are set to close positions (FIGS. 1 and 6), and the elevating drive mechanism 32 is driven to lower the frame holding means 22 from the position shown in FIG. Then, the processed wafer unit 10 is lowered along with the frame holding means 22, and the annular frame 11 is supported by the upper support step portion (support surface 25b) of the pair of temporary placement stages 25. Subsequently, the processed wafer unit 10 is carried out from the temporary placement stage 25 to the outside of the tape expansion device 20 by the carry-in / out mechanism (not shown). Since the slack of the expanding tape 12 is reduced in the heating step carried out earlier, the plurality of chips 16 on the wafer unit 10 are difficult to move with each other when being carried out from the tape expansion device 20, and edge chipping after division processing and the like are performed. Can be prevented.

When the processed wafer unit 10 is carried out from the upper support step portion (support surface 25b) of the pair of temporary placement stages 25, the lower support step portion (support surface 25a) of the pair of temporary placement stages 25 is carried out. The wafer unit 10 before (next to be processed) processed by the tape expansion device 20 can be carried into the wafer. Since the wafer unit 10 is carried out to the outside and the wafer unit 10 is carried in from the outside at the same time, the downtime of the apparatus can be reduced as much as possible. When the loading and unloading of each wafer unit 10 is completed, the state shown in FIG. 1 is reached, and the series of steps described above can be repeated and executed.

As described above, in the tape expansion device 20 of the present embodiment, from the cooling of the expanded tape 12 performed before the wafer 13 and the DAF 17 are split to the heating of the expanded tape 12 performed after the wafer 13 and the DAF 17 are split. This is done on a common stage equipped with a frame holding means 22 and a cooling table 24. That is, it is not necessary to transport the wafer unit 10 to a separately installed heating device in a state where the expanded tape 12 is slackened, and edge chipping or the like due to mutual movement of the chips 16 can be prevented and good division can be realized. Further, the time for transporting the wafer unit 10 to the separately installed heating device is omitted, which contributes to the improvement of the throughput in the entire wafer division processing. Further, by performing cooling and heating of the expanding tape 12 on a common stage, the footprint of the entire device can be reduced and the installation space can be made more efficient.

In the expanding tape expanding step (FIG. 4), the tape expanding device 20 of the present embodiment raises the frame holding means 22 without moving the pressing means 23, but lowers the pressing means 23 to lower the expanding tape 12. It is also possible to adopt a configuration that expands. That is, the tape may be expanded by the relative movement of the pressing means and the frame holding means.

In the present embodiment, the heating means 27 for blowing high-temperature warm air onto the expanding tape 12 is used, but the configuration of the heating means is not limited to this. For example, a contact portion that can be directly contacted with the expanded tape may be provided, and a heating means of a type that heats the contact portion may be provided.

The material of the wafer (workpiece) to be divided by applying the present invention, the type of device formed on the wafer, and the like are not limited. For example, as the workpiece, in addition to the semiconductor device wafer, various workpieces such as an optical device wafer, a package substrate, a semiconductor substrate, an inorganic material substrate, an oxide wafer, a raw ceramic substrate, and a piezoelectric substrate may be used. As the semiconductor device wafer, a silicon wafer after device formation or a compound semiconductor wafer may be used. As the optical device wafer, a sapphire wafer or a silicon carbide wafer after device formation may be used. Further, a CSP (Chip Size Package) substrate may be used as the package substrate, silicon, gallium arsenide or the like may be used as the semiconductor substrate, and sapphire, ceramics, glass or the like may be used as the inorganic material substrate. Further, as the oxide wafer, lithium tantalate or lithium niobate after device formation or before device formation may be used.

Moreover, although each embodiment of the present invention has been described, as another embodiment of the present invention, the above-described embodiments and modifications may be combined in whole or in part.

Further, the embodiment of the present invention is not limited to the above-described embodiment and modification, and may be variously modified, replaced, or modified without departing from the spirit of the technical idea of the present invention. Further, if the technical idea of the present invention can be realized in another way by the advancement of the technology or another technology derived from the technology, it may be carried out by the method. Therefore, the scope of claims covers all embodiments that may be included within the scope of the technical idea of the present invention.

As described above, according to the tape expansion device and the tape expansion method of the present invention, it is possible to prevent edge chipping and the like after wafer division, and to contribute to the reduction of manufacturing errors and the improvement of productivity of the device.

10: Wafer unit 11: Circular frame 12: Expanded tape 13: Wafer 15: Modified layer 16: Chip 17: DAF
20: Tape expansion device 21: Base 22: Frame holding means 23: Pressing means 24: Cooling table 25: Temporary placement stage 26: Frame gripping claw 27: Heating means 35: Roller 36: Upper support 37: Lower support 38 : Plate-shaped mesh material 38a: Suction hole 39: Suction groove 40: Suction means 41: Suction means 42: Cooling means 43: Cooling transmission unit

Claims (4)

A tape expansion device for expanding an expanded tape having a wafer having a plurality of devices formed on a region partitioned by a plurality of scheduled division lines and having an outer peripheral portion mounted on an annular frame.
A loading / unloading mechanism for loading the annular frame into the tape expansion device with the wafer attached to the expanding tape facing vertically downward.
A frame holding means for holding the annular frame on the upper surface in a state where the wafer attached to the expanding tape faces vertically downward, and
An expanding tape is annularly pressed from above between the frame holding means and the outer peripheral edge of the wafer to expand, and a pressing means for dividing the wafer along a split starting point.
A cooling table which is arranged so as to be able to move up and down on the inner peripheral side of the annular pressing means and has a suction hole on the contact surface which abuts over the entire surface of the wafer via the expand tape.
A tape expansion device comprising: a heating means for heating and shrinking the expanded tape extended between the frame holding means and the outer peripheral edge of the wafer. In the tape expansion method using the tape expansion device according to claim 1,
A holding step of holding the annular frame so that the back surface of the expanded tape is located below the relevant contact surface of the cooling table with the wafer facing vertically downward.
After performing the holding step, an expanded tape cooling step in which the back surface of the expanded tape is brought into contact with the corresponding contact surface of the cooling table and a suction force is applied to the suction holes to cool the expanded tape.
An expanded tape expansion step for expanding the expanded tape by relatively moving the frame holding means and the pressing means, and
The expanded tape extended between the frame holding means and the outer peripheral edge of the wafer in a state where the corresponding contact surface of the cooling table is brought into contact with the back surface of the expanding tape and a suction force is applied to the suction holes. A tape expanding method comprising: a heating step of heating and shrinking by the heating means. The cooling table is separated from the expanding tape and the expanding tape expansion step is performed.
The tape expansion according to claim 2, wherein the cooling table is moved toward the expanding tape, and the corresponding contact surface of the cooling table is brought into contact with the back surface of the expanding tape to perform the heating step. Method. In the expanding tape expansion step, the expanding tape is expanded while blowing air from the suction holes at a position where the back surface of the expanding tape abuts on the corresponding contact surface of the cooling table without moving the cooling table. The tape expansion method according to claim 2, wherein the tape is expanded.

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