JP7377654B2 - Die bonding equipment, peeling unit, collet and semiconductor device manufacturing method - Google Patents

Description

The present disclosure relates to a die bonding device, and is applicable to, for example, a die bonder that handles thin dies.

In general, a die bonder that mounts a semiconductor chip called a die on the surface of a wiring board, lead frame, etc. (hereinafter collectively referred to as a board) generally uses a suction nozzle such as a collet to attach the die. The operation (work) of transporting it onto a substrate, applying a pressing force, and performing bonding by heating the bonding material is repeatedly performed.

A die bonding process using a die bonding apparatus such as a die bonder includes a peeling process of peeling a divided die from a semiconductor wafer (hereinafter referred to as wafer). In the peeling process, the dies are pushed up from the back side of the dicing tape using push-up pins or blocks, peeled off one by one from the dicing tape held in the die supply section, and transported onto the substrate using a suction nozzle such as a collet.

In recent years, packages have been made thinner in order to promote high-density packaging of semiconductor devices. For example, a stacked package in which a plurality of dies are three-dimensionally mounted on a wiring board has been put into practical use. When assembling such a stacked package, it is required to reduce the thickness of the die to 30 μm or less in order to prevent an increase in package thickness.

Japanese Patent Application Publication No. 2018-120938

When the die becomes thinner, the rigidity of the die becomes extremely low compared to the adhesive strength of the dicing tape.
An object of the present disclosure is to provide a technique that can improve the rigidity of a die.
Other objects and novel features will become apparent from the description of this specification and the accompanying drawings.

A brief overview of typical features of the present disclosure is as follows.
That is, the die bonding apparatus includes a collet that attracts a die on a dicing tape, a movable stage that comes into contact with a portion of the dicing tape located below the die, and a movable stage that is located on the outside of the dicing tape from the die. A fixing stage that adsorbs a portion, and a peeling unit that peels the die from the dicing tape. The movable stage has a concave portion for bending the die so that the top thereof is concave. The lower surface of the collet has a curved surface that mates with the curved upper surface of the die.

According to the present disclosure, it is possible to improve the rigidity of the die.

Conceptual diagram of a die bonder according to an example viewed from above Diagram explaining the operation of the pickup head and bonding head in FIG. 1 A diagram showing an external perspective view of the die supply section in FIG. 1 A schematic cross-sectional view showing the main parts of the die supply section in Figure 1 Diagram explaining the peeling unit in FIG. 4 A diagram explaining the configuration and operation of the peeling unit in FIG. 4 Figure 7 is a diagram explaining the collet in Figure 2. Flowchart showing a method for manufacturing a semiconductor device using the die bonder of FIG. 1 FIG. 9 is a top view of the peeling unit in the first modification. FIG. 10 is a diagram explaining the configuration and operation of the peeling unit in FIG. 9. FIG. 11 is a diagram explaining the configuration and operation of the peeling unit in FIG. 9. Diagram explaining the collet in FIG. 11

Examples and modifications will be described below with reference to the drawings. However, in the following description, the same constituent elements may be denoted by the same reference numerals and repeated explanations may be omitted. In addition, in order to make the explanation more clear, the drawings may schematically represent the width, thickness, shape, etc. of each part compared to the actual aspect, but these are only examples, and the interpretation of the present invention is It is not limited.

FIG. 1 is a top view schematically showing a die bonder according to an embodiment. FIG. 2 is a diagram illustrating the operation of the pickup head and the bonding head when viewed from the direction of arrow A in FIG.

The die bonder 10, which is an example of a die bonding device, can be roughly divided into a die supply device that supplies dies D to be mounted on a substrate S on which one or more product areas (hereinafter referred to as package areas P) that will become one final package are printed. 1, a pickup section 2, an intermediate stage section 3, a bonding section 4, a transport section 5, a substrate supply section 6, a substrate unloading section 7, and a control section 8 that monitors and controls the operation of each section. . The Y-axis direction is the front-rear direction of the die bonder 10, and the X-axis direction is the left-right direction. A die supply section 1 is arranged on the front side of the die bonder 10, and a bonding section 4 is arranged on the back side.

First, the die supply unit 1 supplies the die D to be mounted on the package area P of the substrate S. The die supply unit 1 includes a wafer holding table 12 that holds the wafer 11 and a peeling unit 13 shown by a dotted line that pushes up the die D from the wafer 11. The die supply unit 1 is moved in the XY-axis directions by a drive means (not shown), and moves the die D to be picked up to the position of the peeling unit 13.

The pickup section 2 includes a pickup head 21 that picks up the die D, a pickup head Y drive section 23 that moves the pickup head 21 in the Y-axis direction, and various drives (not shown) that move the collet 22 up and down, rotated, and moved in the X-axis direction. It has a section and a. The pickup head 21 has a collet 22 (see also FIG. 2) that attracts and holds the pushed-up die D at its tip, picks up the die D from the die supply section 1, and places it on the intermediate stage 31. The pickup head 21 has drive units (not shown) that move the collet 22 up and down, rotate it, and move it in the X-axis direction.

The intermediate stage section 3 includes an intermediate stage 31 on which the die D is temporarily placed, and a stage recognition camera 32 for recognizing the die D on the intermediate stage 31.

The bonding unit 4 picks up the die D from the intermediate stage 31 and bonds it onto the package area P of the substrate S being transported, or stacks it on top of the die already bonded onto the package area P of the substrate S. Bonding in shape. The bonding unit 4 includes a bonding head 41 including a collet 42 (see also FIG. 3) that sucks and holds the die D at the tip, similar to the pickup head 21, and a Y drive unit 43 that moves the bonding head 41 in the Y-axis direction. It has a board recognition camera 44 that takes an image of a position recognition mark (not shown) in the package area P of the board S and recognizes the bonding position. With such a configuration, the bonding head 41 corrects the pickup position and posture based on the imaged data of the stage recognition camera 32, picks up the die D from the intermediate stage 31, and picks up the substrate based on the imaged data of the substrate recognition camera 44. Bond D to the die D.

The transport unit 5 includes a substrate transport claw 51 that grips and transports the substrate S, and a transport lane 52 along which the substrate S moves. The substrate S is moved by driving a nut (not shown) of a substrate transport claw 51 provided on the transport lane 52 with a ball screw (not shown) provided along the transport lane 52 . The substrate transport claw 51 may be driven by a belt. With this configuration, the substrate S is moved from the substrate supply section 6 along the transport lane 52 to the bonding position, and after bonding, is moved to the substrate unloading section 7 and is delivered to the substrate unloading section 7.

The control unit 8 includes a memory that stores a program (software) that monitors and controls the operations of each of the above-mentioned parts of the die bonder 10, and a central processing unit (CPU) that executes the program stored in the memory.

Next, the configuration of the die supply section 1 will be explained using FIGS. 3 and 4. FIG. 3 is a diagram showing an external perspective view of the die supply section of FIG. 1. FIG. 4 is a schematic cross-sectional view showing the main parts of the die supply section of FIG. 1.

The die supply unit 1 includes a wafer holding table 12 that moves in the horizontal direction (XY axis direction) and a peeling unit 13 that moves in the vertical direction. The wafer holding table 12 includes an expand ring 15 that holds the wafer ring 14, and a support ring 17 that horizontally positions the dicing tape 16 held by the wafer ring 14 and to which a plurality of dies D are bonded. The peeling unit 13 is arranged inside the support ring 17.

The die supply unit 1 lowers the expand ring 15 holding the wafer ring 14 when the die D is peeled off. As a result, the dicing tape 16 held by the wafer ring 14 is stretched, the distance between the dies D increases, and the peeling unit 13 acts on the dies D from below the dies D, thereby improving the pick-up performance of the dies D. . The adhesive used to bond the die to the substrate changes from a liquid state to a film form, and a film-like adhesive material called a die attach film (DAF) 18 is pasted between the wafer 11 and the dicing tape 16. There is. In the wafer 11 having the die attach film 18, dicing is performed on the wafer 11 and the die attach film 18. Therefore, in the peeling process, the wafer 11 and die attach film 18 are peeled off from the dicing tape 16. Although the die attach film 18 is attached to the back surface of the die D, the peeling process may be explained without the die D.

Next, the collet 22 attached to the peeling unit 13 and the pickup head 21 will be explained using FIGS. 5 to 7. 5 is a diagram illustrating the peeling unit in FIG. 4, FIG. 5(a) is a top view, and FIG. 5(b) is a sectional view of the movable stage taken along line BB in FIG. 5(a). . FIG. 6 is a diagram explaining the configuration and operation of the peeling unit in FIG. 4, and FIG. 6(a) is a cross-sectional view of the main parts, dicing tape, die, and collet taken along line BB in FIG. 5(a). , FIG. 6(b) is a cross-sectional view of the main parts, dicing tape, die, and collet taken along line CC in FIG. 5(a), and FIG. 6(c) shows the movable stage moved from FIG. 6(a). FIG. 3 is a cross-sectional view of the main parts, dicing tape, die, and collet. 7 is a diagram explaining the collet in FIG. 2, FIG. 7(a) is a side view of the collet and collet holder in direction B, and FIG. 7(b) is a side view of the collet and collet holder in direction C. be.

The casing 131 of the peeling unit 13 has a cylindrical shape and includes a groove 132a as an opening located at the center of the upper surface, a fixed stage 132 around the opening, and a movable stage 133 within the groove 132a. The groove portion 132a has a rectangular shape in plan view where the X-axis direction is longer than the Y-axis direction. The movable stage 133 has a rectangular shape whose planar shape is smaller than the groove portion 132a and whose X-axis direction is longer than the Y-axis direction. The movable stage 133 is movable in the vertical direction (Z-axis direction) and in the X-axis direction, which is a first horizontal direction.

A plurality of suction ports (not shown) are provided on the fixed stage 132 provided at the periphery of the upper surface of the peeling unit 13. Note that a plurality of grooves may be provided to connect the plurality of suction ports. The pressure inside each of the suction port and the groove is reduced by a suction mechanism (not shown) when the peeling unit 13 is raised to bring its upper surface into contact with the back surface of the dicing tape 16 . At this time, the back surface of the dicing tape 16 is sucked downward and comes into close contact with the top surface of the peeling unit 13. The fixed stage 132 tightly contacts the dicing tape 16 around the outside of the die D to be picked up. Note that the suction mechanism of the suction port 141 below the movable stage 133 and the suction mechanism of the fixed stage 132 may be independent, and the suction may be turned ON/OFF individually. The peeling unit 13 includes a slider drive mechanism (not shown) that slides the movable stage 133 based on a command from the control section 8 .

Next, details of the peeling unit 13 and the movable stage 133 will be explained. The upper surface of the casing 131 of the peeling unit 13 includes a fixed stage 132, a groove 132a recessed from the fixed stage 132 toward the inside of the casing 131 of the peeling unit 13, and a groove 132a provided on the outer peripheral side of the peeling unit 13. and a convex portion 132b protruding from the bottom surface of the groove portion 132a. The side surfaces 132f of the groove 132a are on the same plane as the guide surfaces 132g on both sides of the convex portion 132b, and extend linearly from the inner circumferential side to the outer circumferential side of the peeling unit 13. The convex portion 132b is located between the guide surfaces 132g and is a step having a flat surface, and its height is smaller than the depth of the groove portion 132a. The bottom surface of the groove portion 132a and the surface of the convex portion 132b are connected by an inclined surface 132c extending from the bottom surface of the convex portion 132b toward the surface of the convex portion 132b. A suction port 141 serving as a hole communicating with the inside of the peeling unit 13 is provided on the bottom surface of the groove portion 132a.

A movable stage 133 that slides along the direction from the groove 132a to the groove 132a is attached to the groove 132a with substantially the same width as the width between the groove 132a and the side surface 132f. The movable stage 133 has a rear end 133a on the side facing the end surface 132e of the groove 132a along the sliding direction (X-axis direction), and a tip 133c on the side facing the convex portion 132b. The movable stage 133 has a concave shape and includes a mounting section 133h on which the die D is mounted via the dicing tape 16, and an inclined section 133g that slopes downward from the mounting surface following the mounting section 133h. The length of the movable stage 133 in the sliding direction is shorter than the length of the groove portion 132a in the sliding direction, and the thickness of the mounting portion 133h of the movable stage 133 is greater than the depth of the groove portion 132a. When the movable stage 133 is fitted into the groove 132a with a gap from the end surface 132e of the movable stage 132a, the mounting portion 133h on the surface of the movable stage 133 becomes higher than the upper surface of the fixed stage 132. The side surface 133b of the movable stage 133 and the side surface 132f of the groove portion 132a constitute a sliding surface. Further, a gap formed between the rear end 133a of the movable stage 133 and the end surface 132e of the groove portion 132a constitutes a vertical groove that extends vertically toward the inner surface of the peeling unit 13 and sucks the dicing tape 16. Further, the gap formed between the side surfaces 133b on both sides of the movable stage 133 and the side surfaces 132f on both sides of the groove portion 132a constitutes a vertical groove that extends vertically toward the inner surface of the peeling unit 13 and sucks the dicing tape 16.

With the above structure, a U-shaped suction opening 140 surrounded by the side surface 132f, end surface 132e, and guide surface 132g of the groove 132a is formed on the upper surface of the peeling unit 13, and the suction opening 140 is It communicates with the inside of the peeling unit 13.

As shown in FIG. 5(b), the mounting portion 133h on which the die D is placed via the dicing tape 16 of the movable stage 133 becomes thinner as it goes from a position near the rear end 133a side to the front end 133c side. A chamfer 133i is provided on the end 133a. Further, an inclined portion 133g is provided which is inclined from the front surface (upper surface) side toward the back surface (lower surface) side as it goes from the mounting portion 133h to the tip 133c. The part of the mounting part 133h that slopes downward from the rear end 133a side to the tip 133c side has a gentler slope than the slope part 133g.The tip 133c side of the slope part 133g is an area on which the die D is not placed. The length of the mounting portion 133h is shorter than the length of the die D. The back side of the movable stage 133 is flat. As shown in FIG. 6(b), the upper side of a rectangular shape whose Y-axis direction is longer than the Z-axis direction in a cross-sectional view from the X-axis direction (YZ plane perpendicular to the X-axis direction) is formed by a downwardly concave curve. has been done. That is, the surface of the mounting portion 133h forms an upwardly concave curved surface like the inner surface (R-shaped surface) of a circular tube. This causes the die D to curve. Note that the bending caused by the die D due to this curvature is the same as that of the die that is warped on the dicing tape 16 before contacting the peeling unit 13. For example, the height from the bottom of the valley of the curved die D to the end of the die D is greater than 0 μm and less than 20 μm.

Further, the width of the groove 132a, that is, the width of the suction opening 140, is slightly larger than the width of the movable stage 133, and the width of the movable stage 133 and the width of the die D are approximately the same. Each side surface 133b faces each other with a gap in between so as to slide.

As shown in FIG. 7, the collet 22 is attached to a collet holder 25 provided on the pickup head 21. As shown in FIG. As shown in FIGS. 6(a) and 7(a), the collet 22 is shown in side view and cross-sectional view from the Y-axis direction as the second direction. ), and as shown in FIGS. 6(b) and 7(b), the Y The lower side of a rectangular shape whose axial direction is longer than the Z-axis direction is formed with a downwardly convex curve. That is, the suction surface 22a of the collet 22 that suctions the die D forms a convex curved surface like the outer surface (R-shaped surface) of a cylinder. That is, the suction surface 22a of the collet 22 is formed with a convex curved surface so as to fit with the concave curved surface of the mounting portion 133h of the movable stage 133 with the die D and dicing tape 16 in between. This maintains the curvature of the die D.

Next, the pickup operation by the peeling unit 13 having the above-described configuration will be explained using FIGS. 3, 4, and 6.

First, the dicing tape 16 positioned on the wafer holding table 12 shown in FIGS. 3 and 4 is irradiated with ultraviolet light. As a result, the adhesive applied to the dicing tape 16 hardens and its adhesiveness decreases, making it easier for the interface between the dicing tape 16 and the die attach film 18 to separate.

Next, the control unit 8 lowers the expand ring 15 of the wafer holding table 12, thereby pushing down the wafer ring 14 adhered to the peripheral portion of the dicing tape 16. In this way, the dicing tape 16 receives strong tension from its center toward its periphery, and is stretched horizontally without slack.

Next, as shown in FIG. 4, the control unit 8 horizontally moves (pitch-moves) the wafer holding table 12 so that the die D to be picked up is located directly above the peeling unit 13, and the The peeling unit 13 is moved upward so that the upper surfaces of the peeling unit 13 are in contact with each other. At this time, as shown in FIG. 6(a), the rear end 133a of the movable stage 133 is in a position facing the end surface 132e of the groove 132a with a gap therebetween, and the lower surface on the side of the tip 133c of the movable stage 133 is in the groove. It rests on the surface of the groove 132a and is supported by the groove 132a. Further, as shown in FIGS. 6A and 6B, the mounting portion 133h on the surface of the movable stage 133 is higher than the upper surface of the fixed stage 132.

When the upper surfaces of the fixed stage 132 of the peeling unit 13 and the mounting portion 133h of the movable stage 133 come into close contact with the lower surface of the dicing tape 16, the controller 8 stops the lifting of the peeling unit 13. At this time, the control unit 8 attracts the dicing tape 16 using the suction port and groove of the fixed stage 132 and the gap between the fixed stage 132 and the movable stage 133. At this time, as shown in FIG. 6(b), the die D and the dicing tape 16 are curved into a shape that follows the concave curved surface of the upper surface of the mounting portion 133h of the movable stage 133.

The control unit 8 lowers the pickup head 21 (collet 22), positions it above the die D to be picked up, lands the collet 22, and sucks the die D through a suction hole (not shown) of the collet 22. At this time, the convex curved surface of the lower surface of the collet 22 fits into the concave curved surface of the upper surface of the mounting part 133h of the movable stage 133 via the die D and the dicing tape 16, and the curve of the die D is maintained.

The control unit 8 stops the fixed stage 132 and the suction port 141 from suctioning the dicing tape 16 (suction OFF), and slides the movable stage 133. Note that to turn off the adsorption, weak adsorption may be performed at a pressure close to atmospheric pressure.

When the movable stage 133 starts sliding toward the outer circumferential side of the peeling unit 13, the back surface of the movable stage 133 contacts the inclined surface 132c connecting the convex portion 132b and the bottom surface of the groove portion 132a. Then, when the movable stage 133 further slides, the back surface of the movable stage 133 rises along the inclined surface 132c. Then, when the movable stage 133 slides further, the tip 133c of the movable stage 133 crosses the inclined surface 132c, and the back surface of the movable stage 133 comes into contact with the surface of the convex portion 132b. After this, the control unit 8 starts suction using the fixed stage 132 and the suction port 141 at a pressure close to vacuum (suction ON). Since the lower surface of the movable stage 133 is supported by the surface of the convex portion 131b shown in FIG. 6(c), the lower surface of the movable stage 133 is separated from the bottom surface of the groove portion 132a. From this point forward, the movable stage 133 slides with the back surface of the movable stage 133 being substantially parallel to the surface of the groove portion 132a. As a result, a part of the die D located above the suction port 141 is peeled off from the surface 16a of the dicing tape 16, as shown in FIG. 6(c).

When the movable stage 133 is slid, the die D is almost peeled off from the dicing tape 16, so the control unit 8 raises the collet 22 and picks up the die D. After picking up the die D, the control unit 8 returns the movable stage 133 to the initial position, returns the pressure of the suction port 141 and the suction pressure of the fixed stage 132 to atmospheric pressure, and ends the pick-up operation.

Next, a method for manufacturing a semiconductor device using a die bonder according to an embodiment will be described using FIG. 8. FIG. 8 is a flowchart showing a method for manufacturing a semiconductor device using the die bonder of FIG.

(Step S11: Wafer/substrate loading process)
The wafer ring 14 holding the dicing tape 16 to which the die D divided from the wafer 11 is attached is stored in a wafer cassette (not shown) and carried into the die bonder 10. The control section 8 supplies the wafer rings 14 to the die supply section 1 from the wafer cassette filled with the wafer rings 14 . Further, a substrate S is prepared and carried into the die bonder 10. The control section 8 attaches the substrate S to the substrate transport claw 51 using the substrate supply section 6 .

(Step S12: Pick-up process)
The control unit 8 peels off the die D as described above, and picks up the peeled die D from the wafer 11. In this way, the die D peeled off from the dicing tape 16 together with the die attach film 18 is attracted and held by the collet 22 and transported to the next process (step S13). Then, when the collet 22 that has transported the die D to the next process returns to the die supply section 1, the next die D is peeled off from the dicing tape 16 according to the above-described procedure. The dies D are peeled off one by one.

(Step S13: Bonding process)
The control unit 8 mounts the picked up die on the substrate S or stacks it on top of the already bonded die. The control unit 8 places the die D picked up from the wafer 11 on the intermediate stage 31, picks up the die D again from the intermediate stage 31 with the bonding head 41, and bonds it to the substrate S that has been transported.

(Step S14: Substrate unloading process)
The control unit 8 takes out the substrate S to which the die D is bonded from the substrate transport claw 51 in the substrate unloading unit 7 . The substrate S is carried out from the die bonder 10.

As described above, the die D is mounted on the substrate S via the die attach film 18 and is carried out from the die bonder. Thereafter, it is electrically connected to the electrodes of the substrate S via Au wires in a wire bonding process. Subsequently, the substrate S on which the die D was mounted was carried into a die bonder, a second die D was laminated on the die D mounted on the substrate S via the die attach film 18, and the second die D was carried out from the die bonder. Thereafter, it is electrically connected to the electrodes of the substrate S via Au wires in a wire bonding process. After the second die D is peeled off from the dicing tape 16 by the method described above, it is transported to a die bonding process and stacked on the die D. After the above process is repeated a predetermined number of times, the substrate S is transferred to a molding process, and the plurality of dies D and Au wires are sealed with a molding resin (not shown), thereby completing a stacked package.

According to the embodiment, since the sliding movable stage is provided with an R (concave) shape and the die is curved, the moment of inertia of the die can be increased, the rigidity is improved, and it is possible to cope with stress caused by peeling. It becomes possible. An easy-to-understand analogy is that when you hold a thin sheet of paper, such as A4 size copy paper, horizontally and pinch the edge of the thin paper with your fingers, the edge opposite to the pinched edge will droop downward due to the thin paper's own weight. On the other hand, if you curve (deform) a thin piece of paper so that the top is concave and pinch the edge with your fingers, the edge opposite to the pinched edge will not sag downward, and the thin paper will maintain its shape.

As described above, when assembling a stacked package in which a plurality of dies are three-dimensionally mounted on a substrate, it is required to reduce the thickness of the die to 30 μm or less in order to prevent an increase in the package thickness. Note that the thickness of the die is thicker than the thickness of the die attach film. On the other hand, since the thickness of the dicing tape is about 100 μm, the thickness of the dicing tape is 3 to 5 times the thickness of the die.

When an attempt is made to peel such a thin die from the dicing tape, deformation of the die that follows the deformation of the dicing tape is more likely to occur, but with the die bonder of this example, when picking up the die from the dicing tape, Deformation of the die can be reduced. This makes it possible to stabilize peeling of a die having a thickness of 30 μm or less (referred to as a thin die) from the dicing tape. This makes it possible to improve the quality and productivity of thin die including 3D NAND (NAND type flash memory with three-dimensional structure).

<Modified example>
Some typical modifications of the embodiment will be illustrated below. In the following description of the modified example, the same reference numerals as in the above-described embodiment may be used for parts having the same configuration and function as those explained in the above-described embodiment. Regarding the explanation of such portions, the explanations in the above-mentioned embodiments may be used as appropriate within the scope that does not conflict technically. Further, some of the above-described embodiments and all or part of the plurality of modified examples may be applied in combination as appropriate within a technically consistent range.

(First variation)
Next, the configuration of the peeling unit of the first modification will be explained using FIGS. 9 to 11. FIG. 9 is a top view of the peeling unit in the first modification. 10 is a diagram illustrating the configuration and operation of the peeling unit in FIG. 9, FIG. 10(a) is a cross-sectional view of the peeling unit taken along line EE in FIG. 9, and FIG. 10(b) is a cross-sectional view of the peeling unit in FIG. FIG. 3 is a cross-sectional view of the peeling unit taken along line FF. 11 is a diagram explaining the configuration and operation of the peeling unit in FIG. 9, FIG. 11(a) is a cross-sectional view of the peeling unit and collet taken along line EE in FIG. 9, and FIG. 11(b) is a 9 is a cross-sectional view of the peeling unit and collet taken along line FF in FIG.

As shown in FIG. 9, the casing 131 of the peeling unit 13 has a cylindrical shape and includes an opening 132o located at the center of the upper surface, a fixed stage 132 around the opening 132o, and a movable stage 133 inside the opening 132o. A movable stage 133 that moves up and down is provided in the opening 132o, and the fixed stage 132 is provided with a plurality of suction ports (not shown) and a plurality of grooves (not shown). When the peeling unit 13 is raised and its upper surface is brought into contact with the back surface of the dicing tape 16, the pressure inside each of the suction ports and grooves is reduced by a suction mechanism (not shown), and the back surface of the dicing tape 16 is brought into contact with the upper surface of the fixed stage 132. It is designed to be in close contact with the

The movable stage 133 is composed of four blocks 102a to 102d that push the dicing tape 16 upward. The four blocks 102a to 102d are arranged such that an annular block 102b is arranged inside the outermost annular block 102a, an annular block 102c is further arranged inside it, and a columnar block 102d is further arranged inside it. ing.

A gap G is provided between the fixed stage 132 and the outer block 102a and between the four blocks 102a to 102d. The pressure inside these gaps G is reduced by a suction mechanism (not shown), and when the back surface of the dicing tape 16 comes into contact with the top surface of the peeling unit 13, the dicing tape 16 is sucked downward, and the blocks 102a to 102d Closely adheres to the top surface of the

The shape of the block 102a in plan view is rectangular like the die D to be peeled, and its size is slightly smaller than the size of the die D. The size of the frame-shaped block 102b arranged inside the block 102a in plan view is about 1 mm to 3 mm smaller than the size of the block 102a. Further, the size of the block 102c arranged inside the block 102b is smaller than the block 102b by about 1 mm to 3 mm. Further, the size of the block 102d arranged inside the block 102c is about 1 mm to 3 mm smaller than the block 102c. Note that the width of the block 102d is larger than any of the widths (the length between the outer side and the inner side) of the blocks 102a to 102c. In this embodiment, the blocks 102a to 102d have a rectangular shape in consideration of ease of processing, but the shape is not limited to this, and may be, for example, an ellipse.

As shown in FIG. 10, the heights of the upper surfaces of the four blocks 102a to 102d are different from each other in the initial state, and the amount of push-up of block 102a is greater than the amount of push-up of block 102b; The amount of push-up is larger than the amount of push-up of block 102c, the amount of push-up of block 102c is greater than the amount of push-up of block 102d, and the inner block is about 0 to 20 μm lower than the outer block. That is, the heights of the blocks 102a to 102d are set so that the die D and dicing tape attracted to the surface of the movable stage 133 form an upwardly concave curved surface like a spherical surface (SR-shaped surface). This causes the die D to curve. Note that the bending caused by the die D due to this curvature is the same as that of the die that is warped on the dicing tape 16 before contacting the peeling unit 13. Further, the block 102a is slightly lower than the height of the upper peripheral portion of the peeling unit 13 (fixed stage 132).

Each of the blocks 102a to 102d can be moved up and down independently, and the amount of movement can also be changed by the control unit 8.

12 is a diagram explaining the collet in FIG. 11, FIG. 12(a) is a side view of the collet and collet holder in the E direction, and FIG. 12(b) is a side view of the collet and collet holder in the F direction. be.

As shown in FIG. 12, the collet 22 is attached to a collet holder 25 provided on the pickup head 21. As shown in FIG. As shown in FIG. 12(a), the collet 22 has a lower side of a rectangular shape in which the X-axis direction is longer than the Z-axis direction (vertical direction) in a side view and a cross-sectional view from the Y-axis direction (cross-sectional view in the XZ plane). is formed by a downwardly convex curve, and as shown in FIG. 12(b), the Y-axis The lower side of a rectangular shape whose direction is longer than the Z-axis direction is formed by a downwardly convex curve. That is, the attraction surface 22a of the collet 22 that attracts the die D forms a spherical surface (SR-shaped surface). That is, the suction surface 22a of the collet 22 is formed with a convex curved surface so as to fit with the die D formed on the blocks 102a to 102d of the movable stage 133 and the concave curved surface of the dicing tape 16. This maintains the curvature of the die D.

Next, the pickup operation by the peeling unit 13 having the above-described configuration will be explained using FIGS. 3, 4, and 10.

First, similarly to the embodiment, the dicing tape 16 positioned on the wafer holding table 12 shown in FIGS. 3 and 4 is irradiated with ultraviolet light. As a result, the adhesive applied to the dicing tape 16 hardens and its adhesiveness decreases, making it easier for the interface between the dicing tape 16 and the die attach film 18 to separate.

Next, as in the embodiment, by lowering the expand ring 15 of the wafer holding table 12, the wafer ring 14 adhered to the peripheral portion of the dicing tape 16 is pushed down. In this way, the dicing tape 16 receives strong tension from its center toward its periphery, and is stretched horizontally without slack.

Next, as shown in FIG. 4, the center of the peeling unit 13 (blocks 102a to 102d) is positioned directly below one die D to be peeled (die D located in the center of the figure). The wafer holding table 12 is moved, and the collet 22 is moved above the die D. The bottom surface of the collet 22 supported by the pickup head 21 is provided with a suction port (not shown) through which the internal pressure is reduced, so that only one die D to be peeled can be selectively attracted and held. It has become.

Next, as shown in FIG. 10, the upper surfaces of the blocks 102a, 102b, 102c, and 102d are set to different heights and slightly lower than the upper surface of the fixed stage 132 (the initial state described above), The peeling unit 13 is raised to bring its upper surface into contact with the back surface of the dicing tape 16, and the pressure inside the suction port, groove, and gap G of the fixed stage 132 is reduced. As a result, the dicing tape 16 below the other die D adjacent to the die D to be peeled is brought into close contact with the fixed stage 132, and the dicing tape 16 below the die D to be peeled is attached to the blocks 102a to 102d. to form a concave curved surface on the die D and the dicing tape 16. On the other hand, the collet 22 is lowered almost simultaneously with the rise of the peeling unit 13, and its bottom surface is brought into contact with the upper surface of the die D to be peeled, thereby attracting the die D and lightly pressing it downward.

Next, as shown in FIG. 11, the four blocks 102a, block 102b, block 102c, and block 102d are simultaneously pushed upward while maintaining their mutual positional relationships to apply a load to the back surface of the dicing tape 16, and the die D is pushed up together with the dicing tape 16 to peel off the periphery.

Next, when the outermost block 102a is pulled down, the die attach film 18 and the dicing tape 16 begin to peel off. At this time, by sucking the dicing tape 16 below the other die D adjacent to the die D to be peeled downward and keeping it in close contact with the fixed stage 132, peeling of the other die D can be prevented. can. When pulling down the block 102a, the dicing tape 16 below the die D is depressurized inside the gap G between the blocks 102a, 102b, 102c, and 102d to promote peeling of the die D. is sucked downward. Further, the pressure inside the groove of the fixed stage 132 is reduced to bring the dicing tape 16 in contact with the fixed stage 132 into close contact with the upper surface of the fixed stage 132.

Next, when the block 102b placed second from the outermost side is pulled down, the separation between the die attach film 18 and the dicing tape 16 progresses toward the center of the die D. At this time, the top surface of block 102a is located lower than the top surface of fixed stage 132, but the top surface of block 102b is located higher than the top surface of fixed stage 132.

Next, when the block 102c arranged third from the outermost side is pulled down, the separation between the die attach film 18 and the dicing tape 16 further progresses toward the center of the die D. At this time, the top surfaces of blocks 102a, 102b, and 102c are located lower than the top surface of fixed stage 132.

Then, by pulling down the block 102d and pulling up the collet 22, the die attach film 18 is completely peeled off from the dicing tape 16.

According to the first modification, since the die is curved by providing a concave shape with a plurality of blocks constituting the movable stage, it is possible to increase the cross-sectional moment of inertia of the die similarly to the embodiment, improving rigidity and peeling. This makes it possible to cope with the stress associated with

(Second modification)
In the first modification, the outer blocks were pulled down sequentially from the state shown in FIG. 10(b), but the die D may be peeled off from the dicing tape 16 by pushing up sequentially from the inner blocks. That is, first, the block 102d is pushed up higher than the block 102a. Next, block 102c is pushed up higher than block 102a but lower than block 102d. Next, block 102b is pushed up higher than block 102a but lower than block 102c. Next, block 102a is pushed up lower than block 102b.

As above, the invention made by the present inventors has been specifically explained based on the embodiments and modifications, but the present invention is not limited to the above embodiments and modifications, and can be modified in various ways. Needless to say.

For example, in the embodiment, an example was explained in which a convex part (step) for peeling is provided in front of the movable stage, but the movable stage may be moved horizontally without providing a convex part (step), or the movable stage may be moved vertically as well as horizontally.

Furthermore, in the modified example, an example in which the movable stage is composed of four blocks has been described, but it may be composed of less than four blocks or five or more blocks.

In addition, seven rectangular blocks are arranged in parallel to form blocks 102a to 102d, one block in the center forms an inner block 102d, and three blocks on both sides form middle blocks 102a to 102c, The two outermost blocks may constitute the outer block 102a. In this case, the collet 22 has a rectangular shape as in the embodiment, and the lower side of the long rectangle is formed with a downwardly convex curve. A convex curved surface such as an R-shaped surface may be formed.

Further, in the embodiment, an example in which a die attach film is used has been described, but it is also possible to provide a preform portion for applying an adhesive to the substrate and not use a die attach film.

In addition, in the embodiment, a die bonder was described in which a pickup head picks up a die from a die supply unit and places it on an intermediate stage, and the die placed on the intermediate stage is bonded to a substrate using a bonding head. The present invention is applicable to semiconductor manufacturing equipment that picks up dies from a die supply section. For example, the present invention can be applied to a die bonder that does not have an intermediate stage or a pickup head and bonds a die in a die supply section to a substrate using a bonding head.

8: Control unit 10: Die bonder (die bonding device)
13: Peeling unit 132: Fixed stage 133: Movable stage 16: Dicing tape 22: Collet D: Die

Claims (13)

A collet that attracts the die held on the dicing tape,
a movable stage that abuts a portion of the dicing tape located below the die; and a fixed stage that adsorbs a portion of the dicing tape located outside and around the die; a peeling unit for peeling from the
Equipped with
The movable stage has a concave portion for curving the die so that the top thereof is concave, and
The lower surface of the collet has a curved surface that fits with the upper surface of the curved die,
The movable stage has a mounting part whose thickness becomes thinner from the rear end side toward the front end side, and a chamfered part provided at the rear end side of the mounting part,
The movable stage is slidable in a first horizontal direction with respect to the fixed stage,
In a cross-sectional view in a plane perpendicular to the first direction, the lower surface of the collet has a downwardly convex curve, and the upper surface of the movable stage has an upwardly concave curve;
In a cross-sectional view at a central portion of the movable stage in a second direction horizontally perpendicular to the first direction, the lower surface of the collet is a straight line in a plane parallel to the first direction and perpendicular to the second direction. The die bonding apparatus has a shape, and the upper surface of the movable stage is linear . The die bonding apparatus according to claim 1,
The peeling unit further includes a mechanism for deforming the die via the dicing tape by adsorbing the dicing tape. The die bonding apparatus according to claim 1,
A die bonding apparatus, wherein the die has a thickness of 30 μm or less, and a height from the bottom of a valley of the curved die to an end of the die is more than 0 μm and 20 μm or less. The die bonding apparatus according to claim 1,
In a cross-sectional view in a plane orthogonal to the first direction , the upper surface of the mounting portion of the movable stage has an upwardly concave R-shaped surface . The die bonding apparatus according to claim 4,
In a cross-sectional view of a central portion of the mounting portion in the second direction, parallel to the first direction, and perpendicular to the second direction, the upper surface of the mounting portion of the movable stage is linear. Die bonding equipment. A peeling unit used with a collet having a curved surface on a lower surface that fits with a curved upper surface of a die, the stripping unit comprising:
a movable stage that comes into contact with a portion of the dicing tape located below the die to be picked up ;
a fixed stage that adsorbs a portion of the dicing tape located outside and around the die to be picked up;
Equipped with
The movable stage has a concave portion for curving the die to be picked up so that the top thereof is concave, and is slidable in a first horizontal direction with respect to the fixed stage,
The movable stage has a mounting part whose thickness becomes thinner from the rear end side toward the front end side, and a chamfered part provided at the rear end side of the mounting part,
In a cross-sectional view in a plane perpendicular to the first direction, the upper surface of the movable stage has an upwardly concave curve;
In a cross-sectional view at a central portion of the movable stage in a second direction horizontally perpendicular to the first direction, parallel to the first direction and perpendicular to the second direction, the top surface of the movable stage is A peeling unit that is linear . A movable stage that contacts a portion of the dicing tape located below the die, and a fixed stage that adsorbs a portion of the dicing tape that is located outside and around the die, and the movable stage is configured to hold the die above the die. The movable stage has a concave portion for concavely curving the movable stage, and the movable stage has a mounting portion whose thickness becomes thinner from the rear end side toward the front end side, and a chamfered portion provided at the rear end side of the mounting portion. The movable stage is slidable in a first horizontal direction with respect to the fixed stage, and the upper surface of the movable stage has an upwardly concave curve in a cross-sectional view taken in a plane orthogonal to the first direction. and, in a cross-sectional view of the movable stage at a central portion of the movable stage in a second direction horizontally orthogonal to the first direction, in a cross-sectional view in a plane parallel to the first direction and perpendicular to the second direction. A collet used with a peeling unit whose upper surface is linear ,
The lower surface of the collet has a curved surface that fits with the upper surface of the curved die,
In a cross-sectional view in a plane perpendicular to the first direction, the lower surface of the collet has a downwardly convex curve;
In a cross-sectional view at a central portion of the movable stage in a second direction horizontally perpendicular to the first direction, the lower surface of the collet is a straight line in a plane parallel to the first direction and perpendicular to the second direction. The state is
A collet that attracts the curved die held on the dicing tape. A collet that attracts the die held on the dicing tape, a movable stage that comes into contact with a portion of the dicing tape located below the die, and a movable stage that adsorbs a portion of the dicing tape that is located outside and around the die. a fixed stage that peels the die from the dicing tape, a peeling unit that peels the die from the dicing tape, and a control unit that controls the peeling unit, and the movable stage has a concave portion that curves the die so that the top thereof is concave. The lower surface of the collet has a curved surface that fits with the upper surface of the curved die, and the movable stage has a mounting portion whose thickness decreases from the rear end side to the front end side, and the mounting portion of the mounting portion. a chamfered portion provided on the rear end side, the movable stage is slidable in a first horizontal direction with respect to the fixed stage, and in a cross-sectional view in a plane orthogonal to the first direction, the The lower surface of the collet has a downwardly convex curve, the upper surface of the movable stage has an upwardly concave curve, and the collet has a central portion in a second direction horizontally orthogonal to the first direction of the movable stage. A dicing tape is attached to a die bonding apparatus in which the lower surface of the collet is linear and the upper surface of the movable stage is linear in a cross-sectional view in a plane parallel to the first direction and orthogonal to the second direction. a wafer loading step of loading a wafer ring to be held;
a pickup step of peeling and picking up the die from the dicing tape with the peeling unit and the collet;
a bonding step of placing the die picked up from the dicing tape on a substrate;
A method for manufacturing a semiconductor device comprising: The method for manufacturing a semiconductor device according to claim 8 ,
The pickup step includes:
deforming the die via the dicing tape by the peeling unit adsorbing the dicing tape;
the collet attracting the die;
the movable stage sliding in a first horizontal direction relative to the fixed stage;
A method for manufacturing a semiconductor device having the following. The method for manufacturing a semiconductor device according to claim 8 ,
The method for manufacturing a semiconductor device, wherein the die has a thickness of 30 μm or less, and a height from the bottom of the curved valley of the die to the end of the die is more than 0 μm and 20 μm or less. The method for manufacturing a semiconductor device according to claim 8 ,
The method for manufacturing a semiconductor device, wherein the die further includes a die attach film between the die and the dicing tape. The method for manufacturing a semiconductor device according to claim 8 ,
The bonding step includes a step of placing the die on a die that has already been bonded. The method for manufacturing a semiconductor device according to claim 12 ,
The pickup step further includes the step of placing the picked-up die on an intermediate stage,
The method for manufacturing a semiconductor device, wherein the bonding step further includes a step of picking up the die from the intermediate stage.

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