JP2018073990A - Workpiece dividing device and workpiece dividing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a workpiece dividing device and a workpiece dividing method that can eliminate an un-division problem of a dividing line, which may occur in a case where a chip size is small.SOLUTION: A frame 4 for a wafer unit 2 is fixed by a frame fixing member 7 via an expansion restricting ring 16. Next, an expanding ring 14 is moved upward and expansion of the entirety of an annular-part area 3B is initiated. Next, when an amount of upward movement of the expanding ring exceeds the thickness of the frame, the annular part area 3B comes into contact with the expansion restricting ring 16 and expiation of an outer-peripheral-side area 3E, located on the outer-peripheral side of the annular-part area, is restricted. Next, upward movement of the expanding ring is continued and an inner-peripheral side area 3F, excluding the outer-peripheral-side area of the annular-part area, is continuously expanded, thereby dividing the wafer 1 into individual chips 6.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a workpiece dividing apparatus and a workpiece dividing method, and more particularly to a workpiece dividing apparatus and a workpiece dividing method for dividing a workpiece such as a semiconductor wafer into individual chips along a division planned line.

  Conventionally, in the manufacture of semiconductor chips (hereinafter referred to as chips), semiconductor wafers (hereinafter referred to as wafers) in which lines to be divided are formed in advance by half-cutting with a dicing blade or formation of modified regions by laser irradiation. ) Is divided into individual chips along a planned division line (see Patent Document 1 etc.).

  11A and 11B are explanatory views of the wafer unit 2 to which the disk-shaped wafer 1 to be divided by the workpiece dividing apparatus is attached. FIG. 11A is a perspective view of the wafer unit 2, and FIG. 4 is a longitudinal sectional view of a unit 2. FIG.

  The wafer 1 is affixed to the center of a dicing tape 3 (also called an expansion tape or an adhesive sheet) 3 having an adhesive layer formed on one side and having a thickness of about 100 μm. A fixed frame (hereinafter referred to as a frame) 4 is fixed.

  In the workpiece dividing apparatus, the frame 4 of the wafer unit 2 is fixed in contact with a frame fixing member (also referred to as a frame fixing mechanism) 7 indicated by a two-dot chain line. Thereafter, an expanding ring (also referred to as a push-up ring) 8 indicated by a two-dot chain line is moved upward from below the wafer unit 2, and the dicing tape 3 is pressed and expanded radially by the expanding ring 8. The tension of the dicing tape 3 generated at this time is applied to the division line 5 of the wafer 1, whereby the wafer 1 is divided into individual chips 6. The division lines 5 are formed in the X direction and the Y direction orthogonal to each other. When the number of lines to be divided 5 is the same as the number parallel to the X direction and the number parallel to the Y direction, and the intervals in the respective directions are equal, the shape of the divided chip 6 is a square. . In addition, when the number parallel to the X direction is different from the number parallel to the Y direction, and the intervals in the respective directions are equal, the shape of the divided chip 6 is a rectangle.

  Incidentally, the dicing tape 3 is a flexible member having a low Young's modulus. For this reason, in order to smoothly divide the wafer 1 into the individual chips 6, it is conceivable that the dicing tape 3 is cooled and the dicing tape 3 is expanded while the spring constant of the dicing tape 3 is increased.

  The tape expansion device (work dividing device) of Patent Document 2 includes a cold air supply unit. According to Patent Document 2, the dicing tape is cooled by operating the cold air supply means to supply cold air into the processing space and cooling the processing space to, for example, 0 ° C. or lower.

  On the other hand, in the chip dividing / separating device (work dividing device) of Patent Document 3, attention is paid to the fact that the dicing tape has anisotropy, and in order to expand the dicing tape uniformly in consideration of the anisotropy, a film is used. A surface support mechanism is provided. This film surface support mechanism includes a plurality of support mechanisms that are independent in the circumferential direction, and adjusts the tension of the dicing tape by individually controlling the relative heights of the plurality of support mechanisms. The elongation in the direction and the elongation in the Y direction are controlled independently.

  Here, in the present specification, of the dicing tape 3, a circular area in plan view where the wafer 1 is affixed is referred to as a central area 3 </ b> A, and between the outer edge of the central area 3 </ b> A and the inner edge of the frame 4. The planar donut-shaped region provided in FIG. 5 is referred to as an annular portion region 3B, and the planar donut-shaped region at the outermost peripheral portion fixed to the frame 4 is referred to as a fixed portion region 3C. The annular portion region 3B is a region that is expanded by being pressed by the expanding ring 8.

  Note that the force required to divide the wafer 1, that is, the tension that must be generated in the annular region 3 </ b> B in order to divide the wafer 1 may have to be increased as the number of division lines 5 increases. Are known. For example, when the wafer 1 having a diameter of 300 mm and the chip size is 5 mm, about 120 (60 in each of the XY directions) division planned lines 5 are formed and the chip size is 1 mm. Approximately 600 division planned lines 5 are formed. Therefore, the tension that must be generated in the annular portion region 3B must be increased as the chip size is reduced.

JP 2006-149581 A JP-A-2006-12585 Japanese Patent No. 5912274

  Incidentally, the inner diameter of the frame 4 on which the wafer 1 having a diameter of 300 mm is mounted (the diameter of the inner edge of the frame) is set to 350 mm according to the SEMI standard (specification for a tape frame relating to a G74-0699 300 mm wafer). According to this standard, an annular region 3B having a width of 25 mm exists between the outer edge of the wafer 1 and the inner edge of the frame 4 as shown in the longitudinal sectional view of the wafer unit 2 in FIG. . 13A and 13B, the frame fixing member 7 that fixes the frame 4 does not come into contact with the annular portion region 3B that is expanded by the expand ring 8. As described above, the dicing tape 3 is installed at a position spaced outward from the annular portion region 3B in the in-plane direction of the dicing tape 3 indicated by the arrow A.

  For this reason, the force for dividing the wafer 1 caused by the upward movement of the expand ring 8 is (i) the force for expanding the entire region of the annular portion region 3B, (ii) the force for dividing the wafer 1 into the chips 6, and (iii) It is decomposed into three forces of force for expanding the dicing tape 3 between adjacent chips 6.

  14A to 14E, the expanding ring 8 comes into contact with the annular portion region 3B of the dicing tape 3 and expansion of the dicing tape 3 is started by the upward movement of the expanding ring 8. As shown in FIG. (FIG. 14A), first, the expansion of the annular portion region 3B having the lowest spring constant begins (FIG. 14B). As a result, a tension is generated in the annular portion region 3B, and when this tension increases to some extent, the increased tension is transmitted to the wafer 1 to start dividing the wafer 1 into chips 6 (FIG. 14C). When the wafer 1 is divided into individual chips 6, the expansion of the annular portion region 3B and the expansion of the dicing tape 3 between the chips proceed simultaneously (FIGS. 14D to 14E).

  In the conventional workpiece dividing apparatus, when the chip size is 5 mm or more in the wafer 1 having a diameter of 300 mm, it can be divided into the individual chips 6 without problems due to the tension generated in the annular portion region 3B. However, with the miniaturization of the circuit pattern formed on the wafer 1, chips having a smaller chip size of 1 mm or less have also appeared. In this case, the force required to divide the wafer 1 increases due to an increase in the number of scheduled dividing lines 5 for dividing the wafer 1, and a force greater than the tension due to the expansion of the annular region 3B is required. was there. Then, as shown in the longitudinal sectional view of the wafer unit 2 in FIG. 15, even if the expansion operation by the expanding ring 8 is completed, a part of the planned dividing line 5 formed on the wafer 1 remains undivided without being divided. A problem occurred.

  Such an undivided problem of the division line 5 cannot be solved by increasing the expansion amount or expansion speed of the dicing tape 3. For example, when the expansion amount of the dicing tape 3 is increased, the annular portion region 3B starts plastic deformation. Since the spring constant of the annular portion region 3B during plastic deformation is smaller than the spring constant during elastic deformation, the tension that divides the wafer 1 into individual chips 6 in the region beyond the elastic deformation of the annular portion region 3B is Does not occur. On the other hand, even when the expansion speed of the dicing tape 3 is increased, a part of the annular portion region 3B starts plastic deformation, so that tension for dividing the wafer 1 into individual chips 6 does not occur. This is because since the frequency response of the dicing tape 3 is low, no force is transmitted to the entire dicing tape 3 without a time difference.

  In order to solve the undivided problem of the division line 5, Japanese Patent Application Laid-Open No. 2004-228561 copes with this by cooling the dicing tape and increasing the spring constant of the dicing tape. Can not get enough effect.

  In addition, the chip dividing / separating device of Patent Document 3 can independently control the expansion in the X direction and the Y direction of the dicing tape, but applies a force greater than the tension due to the expansion of the annular region to the wafer. Since this is not possible, the problem of undivided lines to be divided cannot be solved.

  The present invention has been made in view of such a problem, and provides a workpiece dividing apparatus and a workpiece dividing method capable of solving the problem of undivided division lines that occur when the chip size is a small chip. With the goal.

  In order to achieve the object of the present invention, the workpiece dividing device of the present invention divides a workpiece adhered to the dicing tape by fixing the outer peripheral portion of the dicing tape to a ring-shaped frame having an inner diameter larger than the outer diameter of the workpiece. In the workpiece dividing device that divides the chip into individual chips along the planned line, the frame fixing member that fixes the ring-shaped frame, and the back surface of the dicing tape on the opposite side of the workpiece attachment surface, are arranged from the inner diameter of the ring-shaped frame. The expansion ring that expands the dicing tape by pressing the back surface of the dicing tape and the frame fixing member are formed separately from the dicing tape. An expansion restriction ring disposed on the same side as the work affixing surface of the tape, the ring An expansion restriction ring that is formed in a ring shape having an opening that is smaller than the inner diameter of the frame and larger than the outer diameter of the expand ring, and that contacts the dicing tape when the dicing tape is expanded by the expand ring. .

  According to the workpiece dividing device of the present invention, after expansion of the dicing tape is started by the expand ring after the frame is fixed by the frame fixing member, the dicing tape comes into contact with the expansion restriction ring when the dicing tape is expanded. At this time, the dicing tape is divided into an outer peripheral side region located on the outer peripheral side and an inner peripheral side region located on the inner peripheral side, with the contact portion being in contact with the expansion restriction ring as a boundary. In the expansion operation by the expanding ring after the dicing tape comes into contact with the expansion restriction ring, the expansion of the outer peripheral area is restricted by the expansion restriction ring, and only the inner peripheral area is expanded. That is, the tension of the spring constant in the inner peripheral region that is larger than the spring constant of the dicing tape is applied to the workpiece. Thereby, since the tension | tensile_strength provided to a workpiece | work increases, the undivided problem of the division | segmentation scheduled line which arises when a chip size is a small chip | tip can be eliminated.

  In one aspect of the present invention, it is preferable that the expansion restriction ring is detachably fixed to the frame fixing member.

  According to one aspect of the present invention, since the expansion restriction ring can be detachably fixed to the frame fixing member, the expansion restriction ring is attached to the frame when the number of lines to be divided formed on the workpiece is larger than the prescribed number. Attach to fixed member. As a result, it is possible to solve the problem of undivision of the line to be divided that occurs when the chip size is a small chip. Also, even if an existing workpiece dividing device that does not have an expansion restriction ring, by attaching the expansion restriction ring to the frame fixing member of the workpiece dividing device, the number of divided division lines is greater than the specified number, that is, A workpiece having a small chip size can be divided and processed.

  On the other hand, when the number of division lines is less than the specified number, the expansion restriction ring is removed from the frame fixing member. If the number of planned division lines is less than the specified number and a workpiece that can be divided without using the expansion restriction ring is divided using the expansion restriction ring, the division division line is divided by the increased tension in the inner peripheral area. In addition, the chip itself may be damaged. Therefore, in the case of a workpiece in which the number of lines to be divided is less than the prescribed number and can be divided without using the expansion restriction ring, it is preferable to detach the expansion restriction ring from the frame fixing member and divide the work into individual chips. .

  In one aspect of the present invention, the opening of the expansion restriction ring is preferably formed in a circular shape.

  According to one aspect of the present invention, in the X direction and the Y direction orthogonal to each other, for example, in the X direction and the Y direction, like a workpiece divided into square chips having the same dimensions in the X direction and the Y direction. In the case of a workpiece having the same number of divided lines (density), it is preferable to use an expansion regulating ring having a circular opening. Similarly, in the case of a work affixed to a dicing tape having the same spring constant in the X direction and the spring constant in the Y direction, it is preferable to use an expansion restricting ring having a circular opening. Thereby, since uniform tension can be given to the peripheral part of a work from the inner peripheral side field expanded, suitable division capacity can be realized to such a work.

  In one aspect of the present invention, the opening of the expansion restriction ring is preferably formed in an elliptical shape.

  According to one aspect of the present invention, in the X direction and the Y direction orthogonal to each other, for example, the workpiece is divided in the X direction and the Y direction, such as a workpiece that is divided into rectangular chips having different dimensions in the X direction and the Y direction. In the case of workpieces having different numbers (density) of lines, it is preferable to use an expansion regulating ring having an elliptical opening.

  In this case, the direction of the minor axis of the ellipse is aligned in parallel with the direction in which the density of the planned dividing line is high (the direction along the short side of the chip, the direction of the high density of the chip), and the direction of the major axis of the ellipse is scheduled to be divided The lines are aligned parallel to the direction in which the line density is low (the direction along the long side of the chip, the direction in which the chip density is low). As a result, since the spring constant is increased in the inner peripheral region located in the direction in which the density of the planned division lines is high, it is possible to apply a suitable tension to the workpiece for dividing the large number of planned division lines. On the other hand, the annular region located in the direction where the density of the planned division lines is low has a small spring constant, but can impart a suitable tension to the work to divide the small division lines. Therefore, it is possible to realize a suitable dividing ability for such a workpiece.

  It is also preferable to use an elliptical expansion restriction ring even in the case of a work affixed to dicing tape having anisotropy in which the spring constant in the X direction and the spring constant in the Y direction are different.

  In this case, the direction of the minor axis of the ellipse is matched with the direction where the spring constant is small, and the direction of the major axis of the ellipse is matched with the direction where the spring constant is large. As a result, when the inner peripheral region is expanded, the spring constant of the inner peripheral region located in the direction parallel to the direction in which the spring constant is small increases, and the inner peripheral side located in the direction parallel to the major axis direction of the ellipse. Since it approaches the spring constant of the region, a substantially uniform tension can be applied to the workpiece from the inner peripheral region. Therefore, it is possible to realize a suitable dividing ability for a work mounted on dicing tape having anisotropy in which the spring constant in the X direction and the spring constant in the Y direction are different.

  In order to achieve the object of the present invention, the work dividing method according to the present invention divides a work affixed to the dicing tape by fixing the outer peripheral portion of the dicing tape to a ring-shaped frame having an inner diameter larger than the outer diameter of the work. A method of dividing a workpiece into individual chips along a predetermined line, using an expanding ring formed in a ring shape having an opening smaller than the inner diameter of the ring-shaped frame and larger than the outer diameter of the workpiece. In the work dividing method of pressing the back surface of the dicing tape opposite to the work surface, a fixing step of fixing the ring frame with the frame fixing member, and an outer diameter of the expand ring that is smaller than the inner diameter of the ring frame An expansion restricting ring formed in a ring shape having a larger opening than the dicing table The expansion process is started by pressing the back surface of the dicing tape by the expansion ring and the dicing tape is expanded, and the dicing tape is brought into contact with the expansion regulating ring when the dicing tape is expanded. And an expansion division step of dividing the work into individual chips.

  According to the work dividing method of the present invention, it is possible to solve the problem of undivided division lines that occur when the chip size is a small chip.

  According to one aspect of the present invention, the expansion division step includes an expansion start step of starting expansion of the dicing tape by pressing the back surface of the dicing tape by an expand ring, and the dicing tape is used as an expansion restriction ring when the dicing tape is expanded. An expansion restricting step for restricting expansion of the outer peripheral region located on the outer peripheral side from the contact portion with the expansion restricting ring of the dicing tape, and removing the outer peripheral region while restricting the expansion of the outer peripheral region. And a dividing step of dividing the work into individual chips by expanding the dicing tape.

  In one aspect of the present invention, it is preferable that the frame fixing member fixes the ring-shaped frame via the expansion restriction ring.

  In one aspect of the present invention, it is preferable to select and use an expansion restriction ring having a diameter of an opening based on the number of workpiece division planned lines from among a plurality of expansion restriction rings having different opening diameters. By changing the diameter of the opening, the width dimension of the inner peripheral side region can be changed, so that the tension applied to the workpiece from the inner peripheral side region can be changed. Since there are a plurality of workpieces with different numbers of division planned lines, it is preferable to provide a plurality of expansion restriction rings with different opening diameters corresponding to the number of division planned lines of the workpieces. . As a result, the expansion restriction ring corresponding to the number of workpiece division planned lines can be selected from a plurality of expansion restriction rings and used.

  According to the present invention, it is possible to solve the problem of undivision of the line to be divided that occurs when the chip size is a small chip.

Main part structure diagram of division stage of workpiece division apparatus of embodiment The principal part expansion perspective view of the division | segmentation stage shown in FIG. Explanatory drawing which showed the modification of an expansion control ring Sectional view of the wafer unit showing the shape of the annular region during expansion Flow chart showing an example of wafer splitting method Flow chart showing another example of wafer splitting method Plan view in which an expansion restriction ring having a circular expansion restriction opening and a wafer unit are stacked. Plan view in which an expansion restriction ring having an elliptical expansion restriction opening and a wafer unit are stacked. Graph showing the expansion rate of the annular region and the inner peripheral region when the expansion restriction ring is not used and when it is used A graph showing the chip split ratio when the extended restriction ring is not used and when it is used Illustration of the wafer unit with a wafer attached Vertical section of wafer unit Side view of main part of work dividing device Operation diagram of work dividing device Longitudinal cross section of wafer unit with wafer divided

  Hereinafter, preferred embodiments of a workpiece dividing apparatus and a workpiece dividing method according to the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the following embodiments, and various modifications and substitutions can be made to the following embodiments within the scope of the present invention.

  FIG. 1 is a longitudinal sectional view of a main part of a division stage provided in a workpiece division apparatus 10 according to the embodiment, and FIG. 2 is an enlarged perspective view of a main part of the division stage. Although the size of the wafer unit to be divided by the workpiece dividing apparatus 10 is not limited, the embodiment exemplifies the wafer unit 2 on which the wafer 1 having a diameter of 300 mm shown in FIG. 12 is mounted.

  The workpiece dividing apparatus 10 is an apparatus that divides the wafer 1 into individual chips 6 along the division line 5. A plurality of division lines 5 are formed in the X and Y directions orthogonal to each other. In the embodiment, the number of the planned division lines 5 parallel to the X direction and the number of the planned division lines 5 parallel to the Y direction are 300, and the distance between them is equal, that is, a chip having a chip size of 1 mm. The wafer 1 divided | segmented into 6 is illustrated.

  As shown in FIGS. 1 and 2, the wafer 1 is attached to the center portion of a dicing tape 3 whose outer peripheral portion is fixed to the frame 4. The dicing tape 3 has a circular central portion region 3A to which the wafer 1 is attached, and an annular portion region 3B having a planar donut shape between the outer edge portion of the central portion region 3A and the inner edge portion of the frame 4. .

  The thickness of the wafer 1 is, for example, about 50 μm. Moreover, as the dicing tape 3, for example, a PVC (polyvinyl chloride) tape is used. The wafer 1 may be attached to the dicing tape 3 through a film adhesive such as DAF (Die Attach Film). As the film adhesive, for example, a PO (polyolefin) -based adhesive can be used.

  The workpiece dividing device 10 includes a frame fixing member 7 for fixing the frame 4 (see FIG. 13: an existing frame fixing member), an expansion regulating ring 16 with which the dicing tape 3 abuts when the dicing tape 3 is expanded, And an expand ring 14 that comes into contact with the annular portion region 3B of the dicing tape 3 from below.

  The expansion restriction ring 16 is configured separately from the frame fixing member 7 and is detachably fixed to the lower surface 7A of the frame fixing member 7. The attachment / detachment structure of the expansion restriction ring 16 with respect to the lower surface 7A is not particularly limited, but may be a fastening structure using a bolt as an example, or a clamping structure using a clamping mechanism.

  The frame fixing member 7 is disposed on the same side of the dicing tape 3 as the application surface of the wafer 1, and the frame 4 is fixed to the lower surface 7 </ b> A via an expansion restriction ring 16. As a result, the expansion restricting ring 16 is held between the frame 4 and the frame fixing member 7.

  Further, the frame fixing member 7 is installed at a position spaced outward from the annular portion region 3B in the in-plane direction of the dicing tape 3 indicated by an arrow A so as not to contact the annular portion region 3B expanded by the expand ring 14. Has been. As shown in FIG. 2, the shape of the frame fixing member 7 is, for example, a ring shape having an opening 7B having a diameter of 361 mm. However, the shape is not particularly limited, and the expansion restricting ring 16 is detachably fixed. Any shape is possible. As the frame fixing member 7, for example, a rectangular plate-like material having an opening 7 </ b> B can be exemplified, and a frame fixing member composed of a plurality of fixing members arranged at predetermined intervals along the outer periphery of the frame 4. Can also be illustrated. The inscribed circle of these fixing members is set equal to the diameter of the opening 7B.

  The expand ring 14 is disposed on the back side of the dicing tape 3 opposite to the wafer 1 application surface, and is an opening for expansion that is smaller than the inner diameter (350 mm) of the frame 4 and larger than the outer diameter (300 mm) of the wafer 1. It is formed in a ring shape having a portion (opening) 14A. The expand ring 14 presses the back surface of the annular portion region 3B of the dicing tape 3 to expand the annular portion region 3B. That is, the expand ring 14 is moved upward in the B direction orthogonal to the in-plane direction indicated by the arrow A of the dicing tape 3 with respect to the annular portion region 3B. As a result, the annular portion region 3B is pushed up by the expand ring 14 and radially expanded. Alternatively, the expanding ring 14 may be fixed and the wafer unit 2 moved downward in the direction of the arrow C to expand the annular portion region 3B with the expanding ring 14. The annular portion region 3 </ b> B comes into contact with the expansion restriction ring 16 during expansion by the expand ring 14.

  The expansion restricting ring 16 is disposed on the same side as the bonding surface of the wafer 1 in the dicing tape 3 and is smaller than the inner diameter (350 mm) of the frame 4 and larger than the outer diameter of the expanding ring 14 (opening for opening restriction) (opening). Part) formed in a ring shape having 16A.

  Although the embodiment has been described in which the expansion regulating ring 16 is detachably provided on the lower surface 7A of the frame fixing member 7 and is held between the frame 4 and the frame fixing member 7, it is not limited thereto. . For example, it may be configured to be detachably fixed to the upper surface 7C of the frame fixing member 7 as in the expansion restricting ring 17A of the first modification shown in FIG. Further, a configuration in which the frame is fixed to the inner peripheral portion of the opening 7B of the frame fixing member 7 in a detachable manner may be employed as in the expansion restriction ring 17B of the second modification shown in FIG. Furthermore, the form fixed to the other structural member (not shown) of the workpiece | work division | segmentation apparatus 10 in the position spaced apart with respect to the frame fixing member 7 may be sufficient.

  FIG. 4 is a longitudinal sectional view of the wafer unit 2 showing the shape of the annular portion region 3 </ b> B being expanded by the expand ring 14.

  As shown in FIG. 4, when the annular portion region 3 </ b> B is expanded by the expand ring 14, the annular portion region 3 </ b> B comes into contact with the expansion restriction ring 16. Specifically, the annular portion region 3B is brought into contact with the inner edge portion 16B of the expansion restricting opening portion 16A.

  In the embodiment, as shown in FIG. 1, the diameter of the expansion restricting opening 16A is set to 338 mm. Thereby, the width dimension of the outer peripheral side area 3E whose expansion is restricted by the expansion restriction ring 16 is set to 6 mm, and the width dimension of the inner peripheral side area 3F excluding the outer peripheral side area 3E in the annular part area 3B is set to 19 mm. Is done.

  Here, in the annular portion region 3 </ b> B, the inner peripheral side region 3 </ b> F whose expansion is not restricted by the expansion restriction ring 16 is a region that substantially contributes to the division of the wafer 1. That is, as the width dimension of the inner peripheral region 3F is reduced, the spring constant of the inner peripheral region 3F is increased, so that the tension applied to the wafer 1 from the inner peripheral region 3F can be increased. Therefore, it is preferable to set the width dimension of the inner peripheral side region 3F in accordance with the number of division planned lines 5.

  Hereinafter, an example of a workpiece dividing method by the workpiece dividing apparatus 10 will be described with reference to the flowchart of FIG. This work dividing method includes a fixing process, an arranging process, and an extended dividing process. The expansion division process includes an expansion start process, an expansion regulation process, and a division process.

  First, in step S100 of FIG. 5, as shown in FIG. 1, the frame 4 of the wafer unit 2 is fixed to the frame fixing member 7 via the expansion restricting ring 16 (fixing step, arrangement step). At this time, when the expansion restricting ring 16 is disposed apart from the frame fixing member 7, the disposing step of the expansion restricting ring 16 and the fixing step by the frame fixing member 7 are performed independently.

  Next, in step S110 in FIG. 5, the expand ring 14 is moved upward in the direction of arrow B from the position in FIG. 1, and expansion of the entire region of the annular portion region 3B is started (expansion start step).

  Next, in step S <b> 120 of FIG. 5, when the upward movement amount of the expand ring 14 exceeds the thickness of the frame 4, the annular portion region 3 </ b> B comes into contact with the expansion restriction ring 16. At this time, as shown in FIG. 4, the annular portion region 3 </ b> B is located on the outer peripheral side region 3 </ b> E located on the outer peripheral side and the inner peripheral side with the contact portion 3 </ b> D contacting the inner edge portion 16 </ b> B of the expansion restriction ring 16 as a boundary. It is divided into an inner peripheral region 3F. In the annular portion region 3B, the expansion of the outer peripheral side region 3E is restricted by the expansion restricting ring 16 (expansion restricting step).

  Next, in step S130 of FIG. 5, the expanding movement of the expand ring 14 is continued, and in the annular portion region 3B, the expansion of the outer peripheral side region 3E is restricted, and the inner peripheral side region 3F excluding the outer peripheral side region 3E is controlled. By continuing the expansion, the wafer 1 is divided into individual chips 6 (division process). Thereafter, the upward movement of the expanding ring 14 is stopped.

  In the dividing step (S130), in the expansion operation by the expand ring 14 after the annular portion region 3B contacts the inner edge portion 16B of the expansion restriction ring 16, the expansion of the outer peripheral side region 3E is restricted by the expansion restriction ring 16. Only the peripheral region 3F is expanded. That is, the tension of the spring constant of the inner peripheral region 3F that is larger than the spring constant of the annular portion region 3B is applied to the wafer 1.

  More specifically, the length of the annular portion region 3B that contributes to the division of the wafer 1 is shortened from 25 mm (width size of the annular portion region 3B) to 19 mm (width size of the inner peripheral region 3F). Increases inversely with it. As a result, even if only the inner peripheral region 3F is expanded, the spring constant of the inner peripheral region 3F is larger than the spring constant of the annular portion region 3B. A tension sufficient to divide the chip 6 can be applied to the wafer 1. Therefore, according to the workpiece dividing apparatus 10, it is possible to solve the problem of undivided division lines that occur when the chip size is a small chip (1 mm).

  The inner edge portion 16B of the expansion restricting ring 16 that is in line contact with the adhesive layer in the annular portion region 3B is subjected to surface processing with an arithmetic average roughness (Ra) of 1.6 (μm) as an example. . Thereby, it is possible to prevent the inner edge portion 16B and the annular portion region 3B from slipping relatively due to the frictional force between the inner edge portion 16B and the annular portion region 3B. In addition, the inner edge portion 16B is chamfered with C0.2 as an example. Thereby, when the expansion force is received from the annular portion region 3B, the annular portion region 3B can be prevented from being broken by the reaction force.

  On the other hand, the work dividing apparatus 10 can employ the following work dividing method in particular because the expansion restriction ring 16 is detachable from the frame fixing member 7.

  FIG. 6 is a flowchart illustrating another example of the work dividing method.

  The work dividing method shown in FIG. 6 determines whether or not to use the expansion restriction ring 16 based on the number of scheduled dividing lines 5 formed on the wafer 1 to be divided, and the wafer 1 is divided into individual chips 6. It is a method of dividing.

  First, in step S200 of FIG. 6, when the number of division lines 5 formed on the wafer 1 is larger than the specified number, that is, when the wafer 1 is divided, the tension exceeds the tension due to the expansion of the annular region 3B. When force is required, the expansion restricting ring 16 is attached to the frame fixing member 7 as described above. Then, the wafer 1 is divided into individual chips 6 through the fixing process in step S100, the expansion process in step S110, the expansion regulation process in step S120, and the division process in step S130 shown in FIG. As a result, it is possible to solve the problem of undivided lines to be divided.

  On the other hand, in step S200 of FIG. 6, when the number of division lines 5 formed on the wafer 1 is less than the prescribed number, that is, when the wafer 1 can be divided by the tension due to the expansion of the annular region 3B. In step S210, the expansion restriction ring 16 is removed from the frame fixing member 7 (expansion restriction ring removal step).

  Next, in step S220, the frame 4 is fixed by the frame fixing member 7 (fixing step).

  Next, in step S230, the annular portion region 3B is expanded by the expanding ring 14, and the wafer 1 is divided into individual chips 6 by the tension of the annular portion region 3B (expansion dividing step).

  When the number of the planned dividing lines 5 is less than the prescribed number and the wafer 1 that can be divided without using the expansion restriction ring 16 is divided using the expansion restriction ring 16, the increased tension of the inner peripheral region 3F is increased. In addition to dividing the planned dividing line 5, the chip 6 itself may be damaged. Specifically, in the wafer 1 having a diameter of 300 mm, the chip 6 itself may be damaged in the wafer 1 in which the number of division lines 5 is 60 and the chip 6 has a chip size of 10 mm. Therefore, in the case of the wafer 1 in which the number of division lines 5 is less than the prescribed number and can be divided without using the expansion restriction ring 16, the expansion restriction ring 16 is removed from the frame fixing member 7 and the wafer 1 is separated into individual chips. It is preferable to divide into 6.

  The prescribed number of division lines 5 is the number that requires a force greater than the tension due to expansion of the annular region 3B when dividing the wafer 1 into individual chips 6. As an example, in the case of the wafer 1 having a diameter of 300 mm shown in FIG. 12, the prescribed number is set to 600.

  Moreover, in the workpiece | work division | segmentation apparatus 10, it is preferable to arrange in advance the several expansion control ring 16 from which the diameter of the opening part 16A for expansion control differs. By changing the diameter of the expansion restricting opening 16A, the width of the inner peripheral region 3F can be changed, so that the tension applied to the wafer 1 from the inner peripheral region 3F can be changed. Since there are a plurality of wafers 1 with different numbers of planned division lines 5, a plurality of expansion regulations with different diameters of expansion regulation openings 16 </ b> A corresponding to the number of planned division lines 5 of those wafers 1. It is preferable to arrange the rings 16. Thereby, the expansion restriction ring 16 corresponding to the number of the division planned lines 5 of the wafer 1 can be selected from the plurality of expansion restriction rings 16 and used. Examples of the diameter of the expansion restricting opening 16A include 346 mm, 342 mm, and 334 mm in addition to 338 mm.

  These expansion restricting rings 16 are preferably stored in advance in a ring storage unit (not shown) provided in the workpiece dividing device 10. One expansion restriction ring 16 selected from among the plurality of expansion restriction rings 16 stored in the ring storage part may be manually removed from the ring storage part and fixed to the frame fixing member 7. You may carry out with a conveying apparatus, and you may convey to the division | segmentation stage of the workpiece | work division apparatus 10. FIG. In addition, the work of carrying out the expansion restriction ring 16 from the ring storage unit, the conveyance work of the expansion restriction ring 16 to the split stage, and the work of fixing the expansion restriction ring 16 to the frame fixing member 7 at the split stage may be automated. .

  Further, since the expansion restriction ring 16 can be attached to and detached from the frame fixing member 7, the expansion restriction ring 16 can be retrofitted to an existing (shipped) work dividing apparatus that does not include the expansion restriction ring 16. Further, the expansion regulating ring 16 corresponding to the number of division lines 5 of the wafer 1 can be retrofitted to an existing workpiece dividing apparatus. Thereby, it is possible to process from a large chip to a small chip using an existing workpiece dividing device. When the chip size is a large chip, that is, when the number of division planned lines 5 is smaller than the prescribed number, the expansion regulating ring 16 can be removed from the existing workpiece dividing apparatus.

  By the way, although it has been explained that the force required to divide the wafer 1 has to be increased as the number of scheduled division lines 5 formed on the wafer 1 increases, depending on the wafer, the X direction and the Y direction orthogonal to each other. The number of the planned division lines 5 parallel to the X direction and the number of the planned division lines 5 parallel to the Y direction (see FIG. 7), or the number of the planned division lines 5 parallel to the X direction , The number of division lines 5 parallel to the Y direction is different (see FIG. 8).

  FIG. 7 is a plan view in which the expansion restriction ring 20 having the circular expansion restriction opening 20A and the wafer unit 2 are overlapped. The wafer 22 shown in FIG. 7 is a wafer in which the number of the planned division lines 5 parallel to the X direction is the same as the number of the planned division lines 5 parallel to the Y direction, and the distance between them is the same. The shape of 24 is a square having the same dimensions in the X and Y directions. That is, the wafer 22 shown in FIG. 7 is a wafer in which the density of the division lines 5 is equal in the X direction and the Y direction. In the case where such a wafer 22 is smoothly divided into individual chips 6, it is preferable to use an expansion restriction ring 20 whose expansion restriction opening 20A is circular. That is, the wafer 22 and the expansion restriction opening 20A are circular, and the inner peripheral side region 3F having a donut shape in plan view surrounded by the outer edge of the wafer 22 and the inner edge of the expansion restriction opening 20A is formed in the circumferential direction. It has the same width dimension e in any position of the throat.

  Thereby, uniform tension can be applied to the peripheral edge of the wafer 22 from the expanded inner peripheral region 3F. That is, by using the expansion restricting ring 20 having the circular expansion restricting opening 20A, a suitable tension is applied to the wafer 22 in order to divide the wafer 22 having the same density of the division lines 5 in the X direction and the Y direction. Can be granted. In addition, it is equivalent that the density of the division | segmentation scheduled line 5 is equal in the X direction and the Y direction, and the density of the chip 6 is equal in the X direction and the Y direction.

  FIG. 8 is a plan view in which the expansion restriction ring 26 having the elliptical expansion restriction opening 26A and the wafer unit 2 are overlapped. A wafer 28 shown in FIG. 8 is a wafer in which the number of planned division lines 5 parallel to the Y direction is larger than the number of planned division lines 5 parallel to the X direction, and the shape of the divided chips 30 is X A rectangle with a short dimension in the direction and a long dimension in the Y direction. That is, the wafer 28 shown in FIG. 8 is a wafer in which the density of the division lines 5 (the density of the chips 6) is different between the X direction and the Y direction. When such a wafer 28 is divided smoothly, it is preferable to use an expansion restriction ring 26 whose expansion restriction opening 26A has an elliptical shape.

  In this case, the direction of the minor axis a of the ellipse of the expansion restricting opening 26A is parallel to the X direction (the direction in which the density of the chip 30 is high, the direction parallel to the short side of the chip 30) of the division line 5 to be high. Accordingly, the direction of the major axis b of the ellipse is aligned in parallel with the Y direction (the direction of low density of the chip 30, the direction parallel to the long side of the chip 30) with the low density of the division line 5.

  As a result, the inner peripheral area 3FA located in the direction parallel to the high-density X direction of the division line 5 has a small width dimension and a high spring constant, so that the high-density division line 5 in the X direction has a high density. A suitable tension for splitting can be applied to the wafer 28.

  On the other hand, the inner peripheral side region 3FB located in the direction parallel to the low Y direction of the division line 5 has a small width and a small spring constant, but the low division density line 5 in the Y direction is divided. Thus, a suitable tension can be applied to the wafer 28. Therefore, it is possible to realize a suitable division capability for the wafer 28 in which the density of the division planned lines 5 is different in the X direction and the Y direction.

  Further, in the dicing tape 3, the spring constant in the X direction and the spring constant in the Y direction are equal, or a difference occurs between the spring constant in the X direction and the spring constant in the Y direction due to the tape generation direction. There is a difference in how the X direction and the Y direction extend. In principle, the direction parallel to the tape production direction tends to extend easily, and the orthogonal direction tends to hardly extend.

  Paying attention to such elongation characteristics of the dicing tape 3, in the case of the dicing tape 3 in which the spring constant in the X direction and the spring constant in the Y direction are equal, the expansion restricting opening 20A as shown in FIG. It is preferable to use the expansion restricting ring 20. Thereby, since the extension amount in the X direction and the extension amount in the Y direction of the inner peripheral side region at the time of expansion become equal, an equal tension can be applied to the wafer from the inner peripheral side region 3F.

  On the other hand, in the case of the dicing tape 3 having anisotropy in which the spring constant in the X direction and the spring constant in the Y direction are different, the expansion restriction ring having the elliptical expansion restriction opening 26A as shown in FIG. Preferably 26 is used.

  In this case, the direction of the minor axis a of the ellipse is matched with the X direction having a small spring constant, and the direction of the major axis b of the ellipse is matched with the Y direction having a large spring constant. As a result, when the inner peripheral side region is expanded, the spring constant of the inner peripheral side region 3FA located in the X direction parallel to the direction in which the spring constant is small increases, and is located in a direction parallel to the direction of the major axis b of the ellipse. Since the spring constant of the inner peripheral region 3FB is approached, a substantially uniform tension can be applied to the wafer from the inner peripheral regions 3FA, 3FB. Therefore, it is possible to realize a suitable dividing ability for the wafer mounted on the dicing tape 3 having anisotropy in which the spring constant in the X direction and the spring constant in the Y direction are different.

  Even in the expansion restricting ring 26 shown in FIG. 8, a plurality of expansion restricting rings 26 having expansion restricting openings 26A having different short diameters a and long diameters b are arranged, and a wafer splitting line is formed from among them. It is preferable to select and use the expansion restriction ring 26 corresponding to the number of five.

  Here, in order to confirm the effect of this invention, the experimental result which this inventor performed is demonstrated.

  The graph of FIG. 9 shows the expansion rate (diameter 350 mm) of the annular region when the expansion restriction ring is not used and the expansion of the inner peripheral side area when the expansion restriction ring is used with respect to the wafer unit 2 of FIG. The expansion rate when the diameter of the expansion restricting opening is set to 346 mm, 342 mm, and 338 mm is shown. Note that “MD (Machine Direction)” in FIG. 9 is a direction parallel to the feed direction when the dicing tape 3 is manufactured, and is a direction having a small spring constant. Further, “CD (Cross Direction)” is a direction orthogonal to MD and having a large spring constant.

  According to the experimental results of FIG. 9, the expansion rate of the annular region when the expansion restriction ring is not used was 6.1% for “MD” and 6.0% for “CD”. On the other hand, as the diameter of the expansion restricting opening is reduced to 346 mm, 342 mm, and 338 mm, the expansion rate of the inner peripheral region is 6.8%, 7.5%, 8.4 for “MD”. In the case of “CD”, it increased to 7.2%, 7.5%, and 8.1%. That is, it was confirmed that as the diameter of the expansion restricting opening was reduced, the chip dividing ability was improved.

  The graph of FIG. 10 shows the chip division rate (diameter 350 mm) when the expansion restriction ring is not used for the wafer unit 2 of FIG. 12 and the chip division ratio when the expansion restriction ring is used. The division ratio when the diameter of the expansion restricting opening is set to 338 mm is shown. Note that the division ratio “with DAF” in FIG. 10 is the division ratio of the chip 6 when the wafer 1 is attached to the dicing tape 3 via the DAF, and the division ratio “without DAF” The division ratio of the chip 6 when the wafer 1 is directly attached to the dicing tape 3.

  According to the experimental results of FIG. 10, when the expansion restriction ring is not used, the division ratio of the chip 6 was 15.0% when “with DAF” and 41.0% when “without DAF”. On the other hand, when using an expansion restriction ring with an expansion restriction opening having a diameter of 338 mm, the split ratio of the tip 6 increases to 61.0% when “with DAF” and 100% when “without DAF”. Rose. In other words, it was confirmed that the division capability of the chip 6 was improved by using the extended restriction ring regardless of whether “DAF is present” or “without DAF”.

  From the above experimental results, according to the workpiece dividing apparatus 10 of the embodiment, the expansion of the outer peripheral side region 3E is restricted by the expansion restricting ring 16, and only the inner peripheral side region 3F is expanded, thereby making it more than the annular portion region 3B. Since the expansion rate is increased and the tension applied to the wafer 1 can be increased, it has been confirmed that the undivided problem of the division line 5 that occurs when the chip size is a small chip can be solved.

  Also, from the above experimental results, as the diameter of the expansion restricting opening of the expansion restricting ring is reduced, the expansion rate of the inner peripheral region increases and the tension applied to the wafer from the inner peripheral region increases. Therefore, it was confirmed that it is preferable to apply an expansion restricting ring having a small diameter of the expansion restricting opening as the number of planned dividing lines increases.

  DESCRIPTION OF SYMBOLS 1 ... Wafer, 2 ... Wafer unit, 3 ... Dicing tape, 3A ... Central part area | region, 3B ... Annular part area | region, 3C ... Fixed part area | region, 3D ... Contact part, 3E ... Outer peripheral side area, 3F ... Inner peripheral side area | region 3 FA: Inner peripheral side region, 3 FB: Inner peripheral side region, 4 ... Frame, 5 ... Divided line, 6 ... Chip, 7 ... Frame fixing member, 8 ... Expanding ring, 10 ... Work dividing device, 14 ... Expanding ring , 14A ... opening for expansion, 16 ... expansion restriction ring, 16A ... opening for expansion restriction, 16B ... inner edge, 17A, 17B, 17C ... expansion restriction ring, 20 ... expansion restriction ring, 20A ... opening for expansion restriction , 22 ... wafer, 24 ... chip, 26 ... expansion restricting ring, 26A ... expansion restricting opening, 28 ... wafer, 30 ... chip

Claims (8)

In a workpiece dividing apparatus in which an outer peripheral portion of a dicing tape is fixed to a ring-shaped frame having an inner diameter larger than the outer diameter of the workpiece, and the workpiece pasted on the dicing tape is divided into individual chips along a planned division line.
A frame fixing member for fixing the ring-shaped frame;
The dicing tape is disposed on the back side opposite to the work sticking surface of the dicing tape, is formed in a ring shape having an opening smaller than the inner diameter of the ring-shaped frame and larger than the outer diameter of the work, and the dicing An expanding ring that expands the dicing tape by pressing the back surface of the tape;
The expansion restricting ring, which is configured separately from the frame fixing member and is disposed on the same side as the work attachment surface of the dicing tape, is smaller than the inner diameter of the ring-shaped frame, and is the expansion ring. An expansion regulating ring that is formed in a ring shape having an opening larger than an outer diameter, and that contacts the dicing tape when the dicing tape is expanded by the expanding ring;
A workpiece dividing device.   The work dividing apparatus according to claim 1, wherein the expansion restriction ring is detachably fixed to the frame fixing member.   The workpiece dividing apparatus according to claim 1, wherein the opening of the expansion restriction ring is formed in a circular shape.   The workpiece dividing apparatus according to claim 1, wherein the opening of the expansion restriction ring is formed in an elliptical shape. A work dividing method in which an outer peripheral portion of a dicing tape is fixed to a ring-shaped frame having an inner diameter larger than the outer diameter of the work, and the work pasted on the dicing tape is divided into individual chips along a predetermined division line. The expanding ring formed in a ring shape having an opening smaller than the inner diameter of the ring-shaped frame and larger than the outer diameter of the workpiece, In the work dividing method of pressing the back side,
A fixing step of fixing the ring-shaped frame with a frame fixing member;
An expansion restricting ring formed in a ring shape having an opening smaller than the inner diameter of the ring-shaped frame and larger than the outer diameter of the expanding ring is disposed on the same side as the application surface of the workpiece in the dicing tape. The placement process;
Expansion of the dicing tape is started by pressing the back surface of the dicing tape with the expanding ring, and the dicing tape is brought into contact with the expansion regulating ring when the dicing tape is expanded, so that the workpiece is made into individual chips. An extended splitting process to split;
A work dividing method comprising: The extended dividing step includes
An expansion start step of starting expansion of the dicing tape by pressing the back surface of the dicing tape by the expanding ring;
When expanding the dicing tape, the dicing tape is brought into contact with the expansion restricting ring, and expansion of the outer peripheral side region located on the outer peripheral side of the dicing tape from the contact portion with the expansion restricting ring is restricted. An extended regulatory process,
A dividing step of dividing the work into individual chips by expanding the dicing tape excluding the outer peripheral region while restricting expansion of the outer peripheral region;
The workpiece dividing method according to claim 5, comprising:   The work dividing method according to claim 5 or 6, wherein the frame fixing member fixes the ring-shaped frame via the expansion restriction ring.   The expansion restriction ring having a diameter of the opening based on the number of the division planned lines of the workpiece is selected and used from among the plurality of expansion restriction rings having different diameters of the opening. Or the work dividing method according to 7.

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