JP2020061453A - Package substrate processing method - Google Patents

Abstract

To provide a package substrate processing method capable of appropriately holding a package substrate on a chuck table while suppressing costs required for dividing the package substrate.SOLUTION: A package substrate processing method includes: an adhesive tape sticking step of sticking an adhesive tape to the rear surface side of a package substrate, the adhesive tape comprising an adhesive layer including an expansion material that expands with external stimulation and having a size corresponding to the package substrate; a division step of holding the package substrate via the adhesive tape using a chuck table and dividing the package substrate into a plurality of device chips; an adhesive force reducing step of reducing adhesive force of the adhesive layer acting on the package substrate by making the expansion material expand by applying external stimulation to the adhesive tape; and a chip housing step of moving the plurality of device chips disposed on the adhesive tape by pressing the device chips using a squeegee to house the plurality of device chips in a housing case.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a method of processing a package substrate used when dividing the package substrate into a plurality of device chips.

  A package substrate is formed by covering a plurality of devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integrations) arranged on a substrate with a sealing material (mold resin) made of resin. The package substrate is divided into a plurality of regions by a plurality of dividing lines (streets) arranged in a grid pattern so as to intersect with each other, and the device is divided by dividing the package substrate along the dividing lines. It is possible to obtain a plurality of device chips (package devices) each of which is included.

  For dividing the package substrate, for example, a cutting device including a chuck table for holding the package substrate and a spindle equipped with an annular cutting blade for cutting the package substrate is used. The package substrate is cut by rotating the cutting blade to cut into the package substrate while holding the package substrate by the chuck table.

  The chuck table that holds the package substrate has a porous suction surface made of, for example, porous ceramics. With the package substrate placed on the suction surface, a negative pressure of a suction source is applied to the suction surface, whereby the package substrate is suction-held by the chuck table.

  When holding the package substrate by the chuck table, first, the package substrate is supported by the annular frame using a circular adhesive tape that can cover the entire back surface of the package substrate. Specifically, the back surface side of the package substrate is attached to the central portion of the adhesive tape, and the annular frame is attached to the outer peripheral portion of the adhesive tape.

  Then, the package substrate is placed on the chuck table via the adhesive tape so that the suction surface of the chuck table is covered with the adhesive tape. As described above, by covering the suction surface of the chuck table with the adhesive tape, leakage of negative pressure of the suction source acting on the suction surface is prevented, and the package substrate is appropriately held by the chuck table.

  On the other hand, a chuck table capable of holding a package substrate without using an adhesive tape has also been proposed. This kind of chuck table is provided with a suction portion corresponding to the shape of the package substrate, and this suction portion is provided with a plurality of suction holes corresponding to respective regions of the package substrate divided by the planned dividing line. (For example, see Patent Document 1).

  The package substrate is arranged on the chuck table so as to cover the suction portion, and the negative pressure of the suction source is applied to the back surface side of the package substrate through the suction holes, whereby the package substrate is suction-held. When this chuck table is used, even after the package substrate is divided into a plurality of device chips, the negative pressure of the suction source acts on each device chip via the suction hole, so that a plurality of device chips are held. Can be maintained.

JP, 2014-73562, A

  When the chuck table having the above-mentioned porous suction surface is used, an adhesive tape larger than the package substrate is attached to the back surface side of the package substrate in order to support the package substrate by the annular frame. Therefore, an adhesive tape having a large area is required to hold the package substrate, and the cost of dividing the package substrate is high.

  On the other hand, when the chuck table that sucks the regions corresponding to the device chips through the suction holes is used, the package substrate can be held without using the adhesive tape. However, the smaller the size of the device chip, the smaller the suction hole corresponding to the device chip, and the weaker the suction force acting on the device chip becomes. Therefore, especially when the package substrate is divided into small device chips, the device chips may be scattered without being properly held by the chuck table.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for processing a package substrate that can appropriately hold the package substrate by a chuck table while suppressing the cost required for dividing the package substrate. .

  According to an aspect of the present invention, there is provided a method of processing a package substrate including a plurality of regions partitioned by a plurality of planned dividing lines arranged in a lattice, the adhesive layer including an expansive material that expands by an external stimulus. And an adhesive tape attaching step of attaching an adhesive tape having a size corresponding to the package substrate to the back surface side of the package substrate, and holding the package substrate by the chuck table via the adhesive tape, A dividing step of dividing the package substrate into a plurality of device chips by cutting the package substrate from the surface side along the dividing line, and applying the external stimulus to the adhesive tape after performing the dividing step. An adhesive strength lowering step of lowering the adhesive strength of the adhesive layer acting on the package substrate by applying and expanding the expandable material. A chip accommodating step of accommodating the plurality of device chips in a housing case by pushing and moving the plurality of device chips arranged on the adhesive tape with a squeegee after the step of reducing the adhesive strength. A method of processing a substrate is provided.

  Further, preferably, the package substrate has a device region in which a device is arranged, and an end material region surrounding the device region, and the chuck table defines a boundary between the device region and the end material region. And a step of holding the package substrate by the chuck table via the adhesive tape and a boundary between the device region and the end material region. Cutting the adhesive tape along with the cutting tape with a cutting blade, dividing the end material region from the device area and removing the end material area, and removing the end material area from the device area of the package substrate. A device region dividing step of cutting along the dividing line and dividing the device region into a plurality of the device chips without dividing the adhesive tape. .

  Further, preferably, in the chip accommodation step, only the device chip obtained by dividing the package substrate is accommodated in the accommodation case.

  In the method of processing a package substrate according to one aspect of the present invention, the package substrate is held by the chuck table via an adhesive tape having a size corresponding to the package substrate. As a result, the amount of the adhesive tape used is reduced as compared with the case where the package substrate is supported by the annular frame, and the cost required for dividing the package substrate is reduced.

  Further, after the package substrate is divided into a plurality of device chips, each device chip is held in a state of being attached to the adhesive tape sucked by the chuck table. As a result, the device chips are securely held on the chuck table, and the device chips are prevented from scattering.

It is a perspective view which shows a package substrate. It is a perspective view showing a cutting device. FIG. 3A is a perspective view showing the package substrate to which the adhesive tape is attached, and FIG. 3B is a sectional view showing the package substrate to which the adhesive tape is attached. FIG. 6 is a perspective view showing how the package substrate is held by a chuck table. FIG. 5A is a partial cross-sectional front view showing a state in which the end material region is divided from the device region, and FIG. 5B is a partial cross-sectional front view showing a state in which the device region is cut. FIG. 6A is a partial cross-sectional front view showing a state where the package substrate is placed on the heating table, and FIG. 6B is a partial cross-sectional front view showing a state in which the device chip is accommodated in the accommodation case. Is.

  The present embodiment will be described below with reference to the accompanying drawings. First, a configuration example of a package substrate that can be processed by the package substrate processing method according to the present embodiment will be described. FIG. 1 is a perspective view showing the package substrate 11.

  The package substrate 11 is made of a metal such as 42 alloy (an alloy of iron and nickel) or copper, and is formed in a plate shape having a front surface 11a and a back surface 11b. FIG. 1 shows an example in which the package substrate 11 is formed in a rectangular shape in a plan view. However, the material, shape, structure, size, etc. of the package substrate 11 are not limited.

  The package substrate 11 includes a plurality of device regions 13 in which devices such as ICs (Integrated Circuits), LSIs (Large Scale Integration), LEDs (Light Emitting Diodes), and MEMSs (Micro Electro Mechanical Systems) are arranged, and a plurality of device regions 13. An end material region 15 that surrounds the device region 13 and is not provided with a device is provided. There is no limitation on the type, quantity, shape, structure, size, arrangement, etc. of the devices arranged in the device area 13.

  Each of the device regions 13 is divided into a plurality of regions 13a by a plurality of dividing lines (streets) 17 arranged in a grid pattern so as to intersect with each other, and the devices are arranged in the regions 13a, respectively. Further, each of the plurality of devices included in the device region 13 is covered with a resin layer (not shown) called a molding resin for sealing the device.

  By dividing the package substrate 11 along the dividing line 17, a plurality of device chips (package devices) including devices sealed with resin can be obtained. For the division of the package substrate 11, for example, a cutting device including a chuck table holding the package substrate 11 and a cutting unit equipped with an annular cutting blade for cutting the package substrate 11 held by the chuck table is installed. Used. A configuration example of the cutting device will be described with reference to FIG.

  FIG. 2 is a perspective view showing the cutting device 2. The cutting device 2 includes a base 4 on which the constituent elements of the cutting device 2 are housed or mounted. The base 4 includes a first surface 4a arranged along the horizontal direction (XY plane direction) and a second surface arranged upward from the rear end of the first surface 4a in the vertical direction (Z-axis direction). 4b and a third surface 4c arranged vertically downward from the front end of the first surface 4a are formed in a stepped shape.

  An opening 4d is formed on one end side of the second surface 4b in the left-right direction (Y-axis direction), and the cassette elevator 6 is arranged inside the opening 4d. The cassette elevator 6 is connected to an elevating mechanism (not shown), and this elevating mechanism elevates and lowers the cassette elevator 6 in the vertical direction. A cassette 8 capable of accommodating a plurality of package substrates 11 (see FIG. 1) is mounted on the upper surface of the cassette elevator 6.

  A temporary placement unit 12 for temporarily placing the package substrate 11 is provided in front of the opening 4d. The temporary placement unit 12 includes a pair of guide rails 14a and 14b that approach and separate while maintaining a state of being parallel to each other. Further, near the guide rails 14a and 14b, an unloading mechanism 16 that holds and pulls out the package substrate 11 housed in the cassette 8 is arranged.

  The carry-out mechanism 16 includes a grip portion 16a that grips the package substrate 11 on the cassette elevator 6 side, and moves in the front-rear direction (X-axis direction) along the first surface 4a of the base 4. Then, the guide rails 14a and 14b sandwich the package substrate 11 pulled out from the cassette 8 by the carry-out mechanism 16, and align the package substrate 11 with each other.

  Further, a slit 4e whose length direction extends along the Y-axis direction is formed above the opening 4d, and the transport arm 18 is inserted inside the slit 4e. A transfer mechanism (not shown) is connected to the base end side (rear end side) of the transfer arm 18, and this transfer mechanism moves the transfer arm 18 along the Y-axis direction.

  A suction pad 22 and an imaging unit 24 are connected to the tip (front end) of the transfer arm 18 via an elevating mechanism 20 such as an air cylinder. A suction source (not shown) is connected to the suction pad 22, and the suction pad 22 suction-holds the package substrate 11 by generating a negative pressure on the lower surface of the suction pad 22 by the suction source. The imaging unit 24 is a camera or the like and acquires an image or the like for adjusting the position at which the package substrate 11 held by the suction pad 22 is transported.

  A rectangular opening 4f is formed in the central portion of the first surface 4a in a plan view from the front of the second surface 4b toward the rear. Inside the opening 4f, an X-axis moving table 26, an X-axis moving mechanism (not shown) for moving the X-axis moving table 26 in the X-axis direction, and a bellows-like dust-proof and drip-proof cover for covering the X-axis moving mechanism. 28 and 28 are arranged.

  A chuck table 30 that holds the package substrate 11 is arranged on the X-axis moving table 26. The chuck table 30 is connected to a rotary drive source (not shown) such as a motor, and rotates about a rotation axis substantially parallel to the Z-axis direction (vertical direction). Further, the chuck table 30 moves along with the X-axis moving table 26 along the X-axis direction.

  The upper surface of the chuck table 30 constitutes a holding surface 30 a that holds the package substrate 11. The holding surface 30a is formed substantially parallel to the X-axis direction and the Y-axis direction, and a suction source (not shown) such as an ejector is provided via a suction path (not shown) provided inside the chuck table 30. )It is connected to the. The details of the structure and function of the chuck table 30 will be described later (see FIG. 4).

  Above the chuck table 30, a cutting unit 32 in which an annular cutting blade 34 that cuts the package substrate 11 is mounted is arranged. The cutting unit 32 is supported by a moving mechanism (not shown), and this moving mechanism moves the cutting unit 32 along the Y-axis direction and the Z-axis direction. Although FIG. 2 shows an example in which the cutting device 2 includes one set of cutting units 32, the cutting device 2 may be provided with two or more sets of cutting units 32.

  The cutting unit 32 includes a spindle (not shown) having an axis in a direction substantially parallel to the holding surface 30a of the chuck table 30, and the cutting blade 34 is attached to the tip of this spindle. The spindle is connected to a rotary drive source such as a motor, and the cutting blade 34 mounted on the spindle is rotated by the force transmitted from the rotary drive source.

  The cutting blade 34 is formed by fixing abrasive grains made of diamond or the like with a bond material. As the bond material, for example, a metal bond, a resin bond, a vitrified bond, or the like is used. By rotating the cutting blade 34 and cutting it into the package substrate 11 arranged on the chuck table 30, the package substrate 11 is cut and divided into a plurality of device chips.

  Further, a cleaning unit 36 for cleaning the upper surface of the package substrate 11 divided into a plurality of device chips by the cutting unit 32 is arranged above the opening 4f. Further, a slit 4g whose length direction extends along the Y-axis direction is formed diagonally above the slit 4e, and the transfer arm 38 is inserted inside the slit 4g.

  A moving mechanism (not shown) is connected to the base end side (rear end side) of the transfer arm 38, and this moving mechanism moves the transfer arm 38 along the Y-axis direction. Further, a suction pad 42 is connected to the tip (front end) of the transfer arm 38 via an elevating mechanism 40 such as an air cylinder.

  A plurality of through holes corresponding to a plurality of device chips obtained by dividing the package substrate 11 are formed on the lower surface side of the suction pad 42, and the through holes are each connected to a suction source (not shown). By generating a negative pressure on the lower surface of the suction pad 42 by this suction source, the divided package substrate 11 (a plurality of device chips) is suction-held by the suction pad 42.

  A cleaning unit 44 for cleaning the lower surface side of the package substrate 11 after division is provided on the side of the opening 4f (the other end in the left-right direction). The package substrate 11 after division is temporarily placed on the side of the cleaning unit 44 (on the other end side in the left-right direction), and a heating table 46 for heating the package substrate 11 is arranged.

  The package substrate 11 divided by the cutting unit 32 is suction-held by the suction pad 42 and is carried out from the chuck table 30. The package substrate 11 sucked and held by the suction pad 42 has its lower surface cleaned by the cleaning unit 44, and then placed on the heating table 46, and the heating process is performed on the package substrate 11 by the heating table 46. (See FIG. 6A).

  Below the slit 4g, a slit 4h whose length direction is along the Y-axis direction is formed, and the accommodation arm 48 is inserted inside the slit 4h. A moving mechanism (not shown) is connected to the base end side (rear end side) of the accommodation arm 48, and this movement mechanism moves the accommodation arm 48 along the Y-axis direction. A squeegee 52 is connected to the tip (front end) of the storage arm 48 via an elevating mechanism 50 such as an air cylinder.

  An opening 4i is formed in a region of the first surface 4a of the base 4 that is located on the side of the heating table 46 (on the other end side in the left-right direction), and the device chip is housed inside this opening 4i. A housing case 54 is provided. Further, the third surface 4c of the base 4 is provided with a drawer 56 for inserting and removing the housing case 54.

  The plurality of device chips mounted on the heating table 46 are pushed out by the squeegee 52 and housed in the housing case 54 through the opening 4i. The details of the structure and function of the squeegee 52 will be described later (see FIG. 6B).

  Further, an operation panel 58 for inputting an instruction or the like to the cutting device 2 is installed on the side of the third surface 4c of the base 4. Information such as cutting conditions is input to the operation panel 58. Further, a monitor 60 for displaying various kinds of information is provided on the second surface 4b of the base 4.

  The cutting device 2 performs a process of dividing the package substrate 11 into a plurality of device chips. Hereinafter, a specific example of the method of processing the package substrate 11 will be described.

  First, an adhesive tape attaching step of attaching the adhesive tape 21 to the back surface 11b side of the package substrate 11 is performed. 3A is a perspective view showing the package substrate 11 to which the adhesive tape 21 is attached, and FIG. 3B is a sectional view showing the package substrate 11 to which the adhesive tape 21 is attached.

  The adhesive tape 21 is formed on the front surface of the base material layer 23 and the base material layer 23 made of a resin such as polyolefin, polyvinyl chloride, or polyethylene terephthalate, and has a predetermined adhesive force to the back surface 11b side of the package substrate 11. The adhesive layer 25 which has. The adhesive tape 21 has a size corresponding to the package substrate 11, and, for example, the size of the adhesive tape 21 and the size of the package substrate 11 are equal. More specifically, the adhesive tape 21 is formed so that its shape matches the shape of the back surface 11b of the package substrate 11.

  Conventionally, when a package substrate is held by a chuck table via an adhesive tape, the package substrate is attached to the central portion of the adhesive tape that is larger than the package substrate, and an annular frame is attached to the outer peripheral portion of the adhesive tape. Thus, the package substrate is supported by the annular frame. Therefore, an adhesive tape having a large area is required to hold the package substrate, and it has been a problem that the package substrate is costly to divide.

  In the method of processing a package substrate according to this embodiment, the adhesive tape 21 having a size corresponding to the package substrate 11 is attached to the back surface 11b side of the package substrate 11. As a result, the amount of the adhesive tape 21 used is reduced, and the cost required for dividing the package substrate 11 is reduced.

  Further, the adhesive layer 25 of the adhesive tape 21 contains an expansive material that expands due to an external stimulus (energy applied from the outside) such as heat or light. For example, the adhesive layer 25 is configured by including the above-mentioned expansive material in an adhesive having a predetermined adhesive force with respect to the back surface 11b side of the package substrate 11.

  As the adhesive, an acrylic adhesive, a rubber adhesive, a vinyl alkyl ether adhesive, a silicone adhesive, a polyester adhesive, a polyamide adhesive, a urethane adhesive, or the like can be used. As the expansive material that expands by an external stimulus, it is possible to use microspheres (thermally expandable microspheres) that expand when heated, or a foam material that foams when heated.

  The heat-expandable microspheres are formed, for example, by encapsulating a substance that expands by heating in elastic microcapsules. As the substance that expands by heating, for example, propane, propylene, butene or the like can be used. As an example of a commercially available adhesive tape 21 provided with an adhesive layer 25 containing heat-expandable microspheres, Riba Alpha (registered trademark) manufactured by Nitto Denko Corporation can be mentioned.

  As the foaming material that is foamed by heating, for example, inorganic foaming agents such as ammonium carbonate, ammonium hydrogencarbonate, sodium hydrogencarbonate, ammonium nitrite, sodium borohydride, and azides, and various organic foaming agents are used. be able to.

  However, the expansive material contained in the adhesive layer 25 is not limited to the substance that expands by heating. For example, an expansive material that expands when irradiated with ultraviolet rays can be used.

  The adhesive tape 21 is attached so that the adhesive layer 25 contacts the back surface 11b side of the package substrate 11. As a result, the entire back surface 11b of the package substrate 11 is covered with the adhesive tape 21.

  Next, the package substrate 11 is held by the chuck table 30 via the adhesive tape 21, and the package substrate 11 is cut from the surface 11a side along the dividing line 17 to divide the package substrate 11 into a plurality of device chips. The dividing step is performed. FIG. 4 is a perspective view showing how the package substrate 11 is held by the chuck table 30.

  The chuck table 30 includes a jig base 70 having a suction path (not shown) inside. The jig base 70 is connected to a rotary drive source (not shown) such as a motor and rotates about a rotation axis substantially parallel to the vertical direction.

  On the upper surface of the jig base 70, a plate-shaped jig 72 formed of a material such as a resin and having a rectangular shape in a plan view is fixed. The upper surface of the jig 72 corresponds to the holding surface 30a (see FIG. 2) of the chuck table 30.

  The jig 72 includes a plurality of suction units 74 that suction the package substrate 11. Each of the plurality of suction portions 74 is provided corresponding to the device region 13 of the package substrate 11, and is formed to have substantially the same shape (rectangular shape) as the device region 13 in a plan view. The suction portion 74 is formed in a porous shape by using, for example, porous ceramics, and is connected to a suction source (not shown) via a suction passage formed inside the jig base 70.

  Further, in the jig 72, a groove 76 whose depth is less than the thickness of the jig 72 is formed from the upper surface to the lower surface of the jig 72. The groove 76 is provided corresponding to the boundary between the device region 13 and the end material region 15 of the package substrate 11, and is arranged so as to surround the suction portion 74. The width of the groove 76 is larger than the width of the cutting blade 34 (see FIG. 2). The groove 76 functions as a clearance groove into which the tip of the cutting blade 34 is inserted when the package substrate 11 is cut by the cutting blade 34 (see FIG. 5A).

  In the dividing step, first, the package substrate 11 is held by the chuck table 30 via the adhesive tape 21 (holding step). Specifically, the back surface 11 b side of the package substrate 11 is arranged on the jig 72 so that the boundary between the device region 13 and the end material region 15 of the package substrate 11 overlaps the groove 76 of the jig 72. As a result, the plurality of suction units 74 are covered with the adhesive tape 21, and the package substrate 11 is suction-held by the chuck table 30 via the adhesive tape 21.

  Next, the package substrate 11 is cut by the cutting blade 34 along the boundary between the device region 13 and the end material region 15, and the end material region 15 is divided and removed from the device region 13 (mill end material region cutting step). FIG. 5A is a partial cross-sectional front view showing a state in which the end material region 15 is divided from the device region 13.

  In the scrap material region dividing step, first, the chuck table 30 is rotated so that the length direction of the one groove 76 is substantially parallel to the machining feed direction (X-axis direction). Further, the height of the cutting unit 32 is set so that the lower end of the cutting blade 34 is arranged below the holding surface 30 a (the upper surface of the jig 72) of the chuck table 30 and above the bottom of the groove 76. adjust. Further, the position of the cutting unit 32 in the Y-axis direction is adjusted so that the cutting blade 34 is arranged on the extension line of the one groove 76 in the length direction.

  In this state, the chuck table 30 is moved along the machining feed direction while rotating the spindle 78 having the cutting blade 34 mounted on the tip thereof. As a result, the cutting blade 34 and the chuck table 30 move relative to each other, the cutting blade 34 cuts into the package substrate 11, and the boundary between the device region 13 and the end material region 15 of the package substrate 11 is cut.

  The cutting of the package substrate 11 is performed while cutting fluid such as pure water is applied to the cutting blade 34 and the package substrate 11. This cutting fluid cools the contact area between the cutting blade 34 and the package substrate 11, and also flushes away the debris generated by cutting.

  When the package board 11 is cut, the lower end of the cutting blade 34 passes through the inside of the groove 76, so that contact between the cutting blade 34 and the jig 72 is avoided. Further, when cutting the package substrate 11, the lower end of the cutting blade 34 is positioned below the lower surface of the adhesive tape 21. Therefore, the cutting blade 34 cuts the package substrate 11 together with the adhesive tape 21.

  After that, the same procedure is repeated to cut the package substrate 11 along all the grooves 76. As a result, the end material region 15 is separated from the device region 13 with a part of the adhesive tape 21 attached. The scrap material region 15 is arranged so as not to overlap the suction portion 74 of the jig 72 (see FIG. 4) and is not sucked by the chuck table 30. Therefore, when the package substrate 11 is cut, the end material region 15 is removed from the chuck table 30 by coming into contact with the rotating cutting blade 34 and scattering, or being washed away by the cutting liquid.

  However, after the execution of the scrap material region cutting step, the cut scrap material region 15 may remain on the chuck table 30. In this case, for example, the rotating cutting blade 34 is moved along the groove 76 to bring the cutting blade 34 into contact with the remaining end material region 15 to scatter the end material region 15 and remove it from the chuck table 30. It may be (mill end material region removing step).

  Next, the device region 13 of the package substrate 11 is cut along the dividing lines 17 to divide the package substrate 11 into a plurality of device chips (device region dividing step). FIG. 5B is a partial cross-sectional front view showing how the device region 13 is cut.

  In the device area dividing step, first, the chuck table 30 is rotated so that the length direction of the one planned dividing line 17 (see FIG. 1) to be processed is substantially parallel to the processing feed direction (X-axis direction). . Further, the height of the cutting unit 32 is set so that the lower end of the cutting blade 34 is arranged below the back surface 11b of the package substrate 11 and above the lower surface of the adhesive tape 21 (the holding surface 30a of the chuck table 30). Adjust the height. Further, the position of the cutting unit 32 in the Y-axis direction is adjusted so that the cutting blade 34 is arranged on the extension line of the one planned dividing line 17 in the length direction.

  In this state, the chuck table 30 is moved along the machining feed direction while rotating the spindle 78 on which the cutting blade 34 is mounted. As a result, the cutting blade 34 and the chuck table 30 relatively move, the cutting blade 34 cuts into the package substrate 11, and the device region 13 is cut along the dividing line 17. At this time, since the lower end of the cutting blade 34 is positioned above the lower surface of the adhesive tape 21, the adhesive tape 21 is not divided.

  After that, the same procedure is repeated, and the package substrate 11 is cut in a lattice shape along all the planned dividing lines 17. As a result, the device area 13 of the package substrate 11 is divided into a plurality of device chips.

  When the package substrate 11 is held by a chuck table having a plurality of suction holes without the adhesive tape 21 as in the conventional case, each device chip has a suction hole after the device region 13 is divided. It is held by the negative pressure acting through it. However, the smaller the device chip size, the smaller the diameter of the suction hole, and the weaker the suction force acting on each device chip. Therefore, the device chips may be scattered without being properly held by the chuck table.

  In the method of processing a package substrate according to this embodiment, the package substrate 11 is suction-held by the chuck table 30 via the adhesive tape 21. Therefore, after the device area 13 is divided, each device chip is held in a state of being attached to the adhesive tape 21 sucked by the chuck table 30. As a result, the device chips are securely held on the chuck table 30, and the device chips are prevented from scattering.

  The package substrate 11 divided into a plurality of device chips is suction-held by the suction pad 42 shown in FIG. At this time, a negative pressure of the suction source acts on each of the device chips 27 via a through hole (not shown) formed on the lower surface side of the suction pad 42. Then, after the adhesive tape 21 attached to the back surface 11 b side of the package substrate 11 is cleaned by the cleaning unit 44, the package substrate 11 is placed on the heating table 46. The cleaning of the adhesive tape 21 prevents the heating table 46 from being soiled.

  Next, an external force is applied to the pressure-sensitive adhesive tape 21 to expand the expansion material contained in the pressure-sensitive adhesive layer 25, thereby performing a pressure-sensitive adhesive force reduction step of reducing the pressure-sensitive adhesive force of the pressure-sensitive adhesive layer 25 acting on the package substrate 11. . Here, an example in which the external stimulus is applied by heating and the adhesive tape 21 is heated by the heating table 46 will be described.

  FIG. 6A is a partial cross-sectional front view showing a state in which the package substrate 11 is placed on the heating table 46. The upper surface of the heating table 46 constitutes a holding surface 46 a that holds the package substrate 11. The package substrate 11 divided into the plurality of device chips 27 is arranged on the heating table 46 so that the adhesive tape 21 contacts the holding surface 46a.

  The holding surface 46 a of the heating table 46 is connected to a suction source (not shown) such as an ejector via a suction path (not shown) provided inside the heating table 46. The package substrate 11 is suction-held by the heating table 46 by applying a negative pressure of the suction source to the holding surface 46 a with the package substrate 11 placed on the heating table 46.

  Further, the heating table 46 includes a heat source 80 such as a heater therein. When the heat source 80 is operated with the package substrate 11 placed on the heating table 46, the adhesive tape 21 is heated by the heat generated by the heat source 80, and the expansive material contained in the adhesive layer 25 expands. As a result, unevenness is formed on the upper surface of the adhesive layer 25, the adhesiveness between the package substrate 11 and the adhesive layer 25 decreases, and the adhesive force of the adhesive layer 25 acting on the package substrate 11 decreases.

  Next, a chip accommodating step of accommodating the device chips 27 in the accommodating case 54 is performed by pushing and moving the device chips 27 arranged on the adhesive tape 21 with the squeegee 52. FIG. 6B is a partial cross-sectional front view showing how the device chip 27 is housed in the housing case 54.

  The squeegee 52 includes a main body portion 82 connected to the elevating mechanism 50 and a plate-shaped eave portion 84 connected to the main body portion 82. The main body portion 82 includes a support portion 82a in the shape of a quadrangular prism that is arranged such that its height direction extends along the X-axis direction, and a push-out portion 82b in the shape of a quadrangular prism that projects downward from the support portion 82a. The push-out portion 82b is provided from the front end (one end side in the X-axis direction) to the rear end (the other end side in the X-axis direction) of the main body portion 82, and the width of the push-out portion 82b in the Y-axis direction is the support portion 82a. Is smaller than the width in the Y-axis direction.

  The body portion 82 is formed of, for example, stainless steel (SUS) or the like. The pushing portion 82b is a region that comes into contact with the device chip 27 arranged on the heating table 46 as described later. Therefore, the extruded portion 82b may be formed of a flexible material such as resin. This makes it difficult for the device chip 27 to be damaged when the pushing portion 82b and the device chip 27 come into contact with each other.

  The eaves portion 84 is in contact with the lower surface of the supporting portion 82a and the side surface of the pushing portion 82b, and is arranged substantially parallel to the holding surface 46a of the heating table 46 from the main body portion 82 toward the opening 4i side of the base 4. . For example, the eaves portion 84 is formed in a rectangular shape in plan view corresponding to the shape of the package substrate 11.

  Further, the eaves portion 84 is formed in a size capable of covering the package substrate 11. Specifically, the length of the eaves portion 84 in the X-axis direction (front-back direction) is longer than the length of the package substrate 11 arranged on the heating table 46 in the X-axis direction. Further, the length of the eaves portion 84 in the Y-axis direction (left-right direction) is longer than the length of the package substrate 11 held on the heating table 46 in the Y-axis direction.

  Note that the squeegee 52 may include a warm air jet nozzle that jets warm air toward the heating table 46. The front surface 11a side of the package substrate 11 is dried by injecting warm air from the warm air jet nozzle while the package substrate 11 is placed on the heating table 46.

  In the chip accommodating step, first, the accommodating arm 48 (see FIG. 2) and the elevating mechanism 50 are operated to adjust the position of the squeegee 52. Specifically, the lower end of the extruded portion 82 b is arranged below the upper surface of the device chip 27 and above the upper surface of the adhesive tape 21 (the upper surface of the adhesive layer 25), and the eaves portion 84 makes a plurality of parts. The squeegee 52 is positioned so that the device chip 27 is covered (see FIG. 6A).

  In this state, the storage arm 48 is moved toward the opening 4i side of the base 4. As a result, the pushing portion 82b comes into contact with the device chip 27 arranged on the heating table 46, and the device chip 27 is pushed toward the opening 4i side.

  At this time, the adhesive force of the adhesive layer 25 in contact with the plurality of device chips 27 is reduced by the above-described adhesive force reducing step. Therefore, as shown in FIG. 6 (B), when the device chip 27 is pushed by the pushing portion 82b of the squeegee 52, the device chip 27 easily moves on the adhesive layer 25. Then, the device chip 27 is put into the opening 4i of the base 4 and housed in the housing case 54 provided inside the opening 4i.

  When the squeegee 52 pushes and moves the device chip 27, the device chip 27 is covered with the eaves portion 84. As a result, the device chips 27 are prevented from scattering, and the device chips 27 can be reliably put into the opening 4i of the base 4.

  Further, the package substrate 11 is arranged on the heating table 46 in a state where the end material region 15 is removed (see FIG. 5A). Therefore, when the device chip 27 is housed in the housing case 54 using the squeegee 52, the end material region 15 is prevented from being mixed into the housing case 54, and only the device chip 27 is housed in the housing case 54.

  As described above, in the method of processing a package substrate according to this embodiment, the package substrate 11 is held by the chuck table 30 via the adhesive tape 21 having a size corresponding to the package substrate 11. As a result, the amount of the adhesive tape 21 used is reduced as compared with the case where the package substrate 11 is supported by the annular frame, and the cost required for dividing the package substrate 11 is reduced.

  After the package substrate 11 is divided into a plurality of device chips, each device chip is held in a state of being attached to the adhesive tape 21 sucked by the chuck table 30. As a result, the device chips are securely held on the chuck table 30, and the device chips are prevented from scattering.

  Further, in the method of processing a package substrate according to the present embodiment, the package substrate 11 is held via the adhesive tape 21 including the adhesive layer 25 containing an expansive material that expands by an external stimulus. Then, the adhesive force of the adhesive layer 25 acting on the package substrate 11 is reduced by applying an external stimulus to the adhesive tape 21 to expand the expandable material, and then a plurality of squeegees 52 provided in the cutting device 2 are used. The device chips 27 are collectively housed in the housing case 54. This allows the device chips 27 to be automatically and easily accommodated.

  In addition, in the present embodiment, an example in which an external stimulus (heat) is applied to the adhesive tape 21 by the heating table 46 including the heat source 80 has been described (see FIG. 6A), but a method of applying the external stimulus is described. It is selected according to the material of the expansion material contained in the adhesive layer 25 of the adhesive tape 21 and the like. For example, when the adhesive layer 25 contains an expansive material that expands by irradiation with ultraviolet rays, a table including an ultraviolet light source is used instead of the heating table 46. By irradiating the adhesive tape 21 with ultraviolet rays from this ultraviolet light source, the adhesive strength of the adhesive layer 25 can be reduced.

  In addition, the cutting device 2 may include an adhesive tape recovery unit that recovers the used adhesive tape 21. Specifically, the accommodating arm 48 may be equipped with an adhesive tape holding member (not shown) that suction-holds the used adhesive tape 21 remaining on the heating table 46 after accommodating the device chips 27. Further, a tape accommodating portion (not shown) in which the used adhesive tape 21 is accommodated may be provided around the heating table 46.

  After the device chip 27 is housed in the housing case 54, the used adhesive tape 21 placed on the heating table 46 is sucked and held by the adhesive tape holding member. Then, after the adhesive tape 21 is moved to the tape accommodating portion by the accommodating arm 48, the suction holding of the adhesive tape 21 by the adhesive tape holding member is released. As a result, the used adhesive tape 21 can be automatically collected.

  In addition, the structures, methods, and the like according to the above-described embodiments can be appropriately modified and implemented without departing from the scope of the object of the present invention.

11 package substrate 11a front surface 11b back surface 13 device area 13a area 15 end material area 17 planned division line (street)
21 Adhesive tape 23 Base material layer 25 Adhesive layer 27 Device chip 2 Cutting device 4 Base 4a 1st surface 4b 2nd surface 4c 3rd surface 4d, 4f, 4i opening 4e, 4g, 4h slit 6 cassette elevator 8 cassette 12 temporary Placement unit 14a, 14b Guide rail 16 Carrying out mechanism 16a Grip 18 Transfer arm 20 Lifting mechanism 22 Suction pad 24 Imaging unit 26 X-axis moving table 28 Dustproof / splash cover 30 Chuck table 30a Holding surface 32 Cutting unit 34 Cutting blade 36 Cleaning unit 38 Transport Arm 40 Lifting Mechanism 42 Suction Pad 44 Cleaning Unit 46 Heating Table 46a Holding Surface 48 Storage Arm 50 Lifting Mechanism 52 Squeegee 54 Storage Case 56 Drawer 58 Operation Panel 60 Monitor 70 Jig Base 72 Jig 4 suction portion 76 the groove 78 the spindle 80 the heat source 82 the main body portion 82a supporting portion 82b extrusion portion 84 overhanging portion

Claims (3)

A method of processing a package substrate comprising a plurality of regions partitioned by a plurality of planned dividing lines arranged in a lattice,
An adhesive tape attaching step of attaching an adhesive tape having an expansion material that expands due to external stimulus, the adhesive tape having a size corresponding to the package substrate, to the back surface side of the package substrate,
A dividing step of dividing the package substrate into a plurality of device chips by holding the package substrate by a chuck table via the adhesive tape and cutting the package substrate from the surface side along the dividing line;
An adhesive strength lowering step of lowering the adhesive strength of the adhesive layer acting on the package substrate by applying the external stimulus to the adhesive tape to expand the expandable material after performing the dividing step;
A chip accommodating step of accommodating the device chips in the accommodating case by pushing and moving the device chips arranged on the adhesive tape with a squeegee after the adhesiveness lowering step is performed. And a method of processing a package substrate. The package substrate has a device region in which devices are arranged, and an end material region surrounding the device region,
The chuck table has a groove at a position corresponding to a boundary between the device region and the end material region,
The dividing step is
A holding step of holding the package substrate by the chuck table via the adhesive tape;
An edge material region dividing step of cutting the package substrate together with the adhesive tape along a boundary between the device region and the edge material region with a cutting blade, and dividing and removing the edge material region from the device region,
A device region dividing step of cutting the device region of the package substrate from which the end material region has been removed along the dividing line, and dividing the device region into a plurality of the device chips without dividing the adhesive tape. The method for processing a package substrate according to claim 1, further comprising:   3. The method of processing a package substrate according to claim 1, wherein in the chip accommodation step, only the device chip obtained by dividing the package substrate is accommodated in the accommodation case.