JP4234300B2 - Chip transfer device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a posture maintaining transfer system for transferring a chip from a chip supply unit such as a wafer holder or a chip tray, for example, in a die-bonding manner, with the circuit forming surface facing up, and a flip chip, for example. As in the case of bonding, it is equipped with both a posture reversal transfer method in which the supply posture in the chip supply unit is turned upside down during transfer and the circuit forming surface is faced down and transferred. The present invention relates to a chip transfer device used for selective execution.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a chip transfer device in a die bonder that transfers a face-up chip in its supply posture from a chip supply unit and bonds it to a substrate is known as a chip transfer device that adopts a posture maintenance transfer method. Further, as a chip transfer device that adopts the posture reversal transfer method, there is a chip transfer device in a flip chip bonder that converts the face-up chip into a face-down state by flipping it upside down and bonds the face-down chip to the substrate. Are known.
[0003]
A chip transfer device in a die bonder includes a head that horizontally moves in the X-axis direction and the Y-axis direction, and a collet that moves up and down relative to the head. The wafer transfer is performed by dicing a wafer from a wafer sheet that holds a large number of chips. One chip is vacuum-sucked by the raising / lowering operation of the collet, and the head is horizontally moved to the substrate in this state, and the chip is bonded to the substrate again by the raising / lowering operation of the collet (for example, Japanese Patent Laid-Open No. 7-143). -297213).
[0004]
Further, a chip transfer device in the flip chip bonder includes a vertical shaft body, an arm projecting horizontally from the vertical shaft body, and a head provided downward from the tip of the arm, the vertical shaft body and the arm, Are connected by a pair of bevel gears meshing with each other. Then, when one head is vacuum-sucked by lifting and lowering the head from the wafer sheet and the vertical axis body is rotated 180 degrees around the vertical axis, the head moves around the vertical axis to the transfer position, and at the same time, The rotational force around the vertical axis is transmitted as the rotational force that rotates the arm around the horizontal axis via the pair of bevel gears. As a result, the head is turned upside down and turned upward to convert the chip into a face-down state. (See, for example, JP-A-9-64104).
[0005]
[Problems to be solved by the invention]
However, in the conventional chip transfer device, it is necessary to use a die bonder to bond the chip to the substrate in a face-up state, while using a flip chip bonder to bond the chip to the substrate in a face-down state. There is a need. In other words, it is necessary to use a dedicated chip transfer device depending on the bonding posture of the chip to the substrate, that is, face-up state or face-down state. There is a disadvantage that it is necessary to supply later wafers individually.
[0006]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a chip transfer device capable of performing both the posture maintenance transfer method and the posture inversion transfer method with the same device. It is in.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a posture maintaining transfer method for transferring a chip from the chip supply unit while maintaining the supply posture in the chip supply unit, and the chip with the upside down operation from the supply posture. A first suction head for sucking and transferring a chip from the chip supply unit in a horizontal direction as a chip transfer device that selectively executes transfer of the chip by both transfer methods of posture reversal transfer method transferred from the chip supply unit; A reversing drive unit for selectively reversing the first suction head in a state where the chip is sucked by rotation about a horizontal axis, and a chip sucked in the first suction head in a non-reverse driving state as the first suction. A transfer stage that is placed away from the head, a first suction head that is vertically inverted by the inversion drive unit, and a chip from any of the transfer stages Selectively adsorbed are those where the structure and a second suction head for transferring to the substrate for the mounting.
[0008]
According to the present invention, the chip is transferred by the posture maintaining transfer method by sucking the chip from the chip supply unit by the first suction head, transporting the suction head that sucked the chip to the transfer stage in the horizontal direction, and transferring the chip. This can be done by separating the chips adsorbed on the stage and placing them on the transfer stage. That is, the chip placed on the transfer stage is sucked by the second suction head, so that the chip having the same posture as the supply posture in the chip supply unit can be transferred to the substrate. As a result, if the chip supply posture in the chip supply unit is in the face-up state, the chip can be transferred in the face-up state.
[0009]
On the other hand, the transfer of the chip by the posture reversal transfer method is performed by sucking the chip from the chip supply unit by the first suction head and operating the reverse drive unit while moving the suction head that sucked the chip in the horizontal direction. It becomes possible. In other words, the first suction head rotates about the horizontal axis by the operation of the reversal drive unit, and the top and bottom are reversed, so that the chip posture can be converted into a state where the top and bottom are reversed from that in the chip supply unit. . Then, the chip whose posture is inverted from the first suction head in the upside down state can be sucked by the second suction head and transferred to the substrate to be mounted. As a result, if the chip supply posture in the chip supply unit is in the face-up state, the chip can be converted into the face-down state and transferred.
[0010]
In this way, both the posture maintenance transfer method and the posture conversion transfer method can be selectively executed by the same apparatus.
[0011]
The chip supply unit in the above invention is configured to include an ejector unit that pushes the chip upward from the lower position when the chip is sucked by the first suction head, and the ejector unit includes a plurality of types corresponding to the chip size. The ejector pin unit may be configured to include a conversion drive unit that mutually converts the position of the plurality of types of ejector pin units by rotation. As a result, it can be converted into an appropriate ejector pin unit according to the chip size, and the chip can be more reliably removed from the wafer sheet. As the above-mentioned plural types of ejector pin units, ones having one or a plurality of ejector pins arranged in accordance with the chip size may be used, and rotation for position conversion is performed. The rotation may be about a vertical axis or a horizontal axis.
[0012]
Furthermore, as the first suction head in the above invention, a central shaft body arranged in the horizontal direction, a plurality of head portions arranged so as to protrude radially from the central shaft body, and the central shaft body And a rotation drive unit that positions a specific head unit selected from the plurality of head units according to the chip size downward by rotating about the central axis. Thereby, it can convert into a suitable specific head part according to the size of the chip | tip supplied by the chip | tip supply part, and can adsorb | suck and transfer more reliably.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0014]
FIG. 1 is a plan view of a composite mounting machine to which a chip transfer device according to an embodiment of the present invention is applied.
[0015]
This composite mounting machine has a component supply unit 4 for a mounted printed circuit board 3 (a circuit board indicated by a two-dot chain line in the figure) which is transported by a conveyor 2 arranged on a base 1 and stopped at a mounting position. A hybrid mounter capable of mounting and mounting both a completed electronic component such as a semiconductor package, a transistor, a capacitor, and the like and a bare chip (chip) 61 from the chip supply unit 62.
[0016]
The said component supply part 4 is arrange | positioned in the one side position on both sides of the conveyor 2. FIG. The component supply unit 4 is provided with a multi-row tape feeder 4a, and each tape feeder 4a accommodates different kinds or the same kind of completed electronic components as described above at predetermined intervals, and draws out the held tape from the reel. The tape is fed out by a ratchet type feeding mechanism, and the tape is intermittently fed out as components are picked up by a mounter head unit 5 described later.
[0017]
A mounter head unit 5 including a second suction head is provided above the base 1, and the mounter head unit 5 is disposed between the component supply unit 4 and a transfer stage 63 (described later) and the printed circuit board 3 in the X axis. It can be moved horizontally in the direction (the direction in which the conveyor 2 is disposed) and the Y-axis direction (the direction perpendicular to the X-axis on the plane).
[0018]
Specifically, a pair of rails 6 extending in the Y-axis direction are extended on the base 1, and a head unit support member 7 is installed on the rails 6. The head unit support member 7 is screwed with a ball screw shaft 9 via a nut portion 8, and the ball screw shaft 9 is connected to a rotation shaft of a Y-axis servo motor 10. The head unit support member 7 has a guide member 11 extending in the X-axis direction, and the mounter head unit 5 is movable along the guide member 11. The mounter head unit 5 is moved in the X-axis direction through a ball screw shaft 13 (see FIG. 2) disposed in parallel with the guide member 11 by driving the X-axis motor 12.
[0019]
As shown in detail in FIG. 2, the mounter head unit 5 includes a head unit main body 15 and a support member supported so as to be movable up and down in the Z-axis direction (vertical direction) as a uniaxial direction with respect to the head unit main body 15. The frame 16 is supported by a second suction head 20 for mounting and mounting the completed electronic component and the bare chip 61 on the substrate 3 in a detachable manner by vacuum suction.
[0020]
The frame 16 is moved up and down with respect to the head unit main body 15 by a vertical movement servo motor 21 fixed to the head unit main body 15. That is, when the frame 16 is moved up and down by the servo motor 21, the second suction head 20 is moved up and down synchronously.
[0021]
Specifically, a guide portion 22 and a ball screw shaft 23 extending in the vertical direction are fixed to the head unit main body 15, while a nut portion 24 screwed to the ball screw shaft 23 is fixed to the frame 16. It is fixed. The ball screw shaft 23 is connected to the rotating shaft of the servo motor 21. When the servo motor 21 is rotated forward or backward, the ball screw shaft 23 rotates at a fixed position around the Z axis, As a result of the nut portion 24 moving up and down along the guide portion 22 along with this rotation, the frame 16 is moved up and down in the Z-axis direction.
[0022]
A plurality of the second suction heads 20 are arranged in the X-axis direction, and each second suction head 20 is individually moved up and down in the Z-axis direction by an air cylinder 25 fixed to the frame 16. In addition, the rotary servomotor is rotated around an axis arranged in the Z-axis direction by a rotation servo motor (not shown).
[0023]
The second suction head 20 is formed with an air passage penetrating through the piston 26 and the hollow shaft 27 of the air cylinder 25, and negative pressure or By supplying the positive pressure in a switchable manner, the second suction head 20 sucks the completed component or the like and separates the sucked component.
[0024]
Further, a suction nozzle 29 is detachably coupled to the tip of the second suction head 20, and the suction nozzle 29 is installed at the other side position of the conveyor 2 (see FIG. 1). Can be replaced with various suction nozzles prepared according to the suction target (completed electronic component and bare chip).
[0025]
In FIG. 1, reference numeral 31 denotes a component recognition camera that images the component sucked by the second suction head 20.
[0026]
On the other hand, the bare chip 61 is supplied to a space 60 on the opposite side of the component supply unit 4 with the conveyor 2 interposed between the pair of Y-axis direction rails 6 and 6 for the mounter head unit 5. A chip supply unit 62 and a chip transfer device 64 for transferring the bare chips 61 from the chip supply unit 62 to the transfer stage 63 one by one are provided.
[0027]
The chip supply unit 62 is disposed close to the end of the rail 6 on one side of the space 60 in the X-axis direction (right side in FIG. 1), and the transfer stage 63 is located on the other side in the X-axis direction (left side in the figure). The chip transfer device 64 extends from the chip supply unit 62 to the transfer stage 63 in an oblique direction on the same plane as the X and Y axes. Has been placed.
[0028]
The chip supply unit 62 includes an XY stage 65 that moves and adjusts in the X-axis direction and the Y-axis direction, and a drawer unit 68 that pulls out one wafer holder 67 from the wafer accommodating elevator 66 and transfers it to the XY stage 65. Has been. The wafer accommodating elevator 66 accommodates a plurality of (for example, ten) wafer holders 67 in multiple stages in the vertical direction, and allows them to be raised and lowered so that any wafer holder 67 can be adjusted to a height position corresponding to the drawer unit 68. It is like that. Each wafer holder 67 holds a large number of bare chips 61 formed by dicing a wafer on a wafer sheet 69 in a face-up state.
[0029]
The drawer unit 68 includes, for example, a guide 71 extending in the Y-axis direction, a cylinder 72 supported by the guide 71 so as to be movable in the Y-axis direction, and a rod end of the cylinder 72 connected to the rod end of the cylinder 72. A hook 73 that is detachably engaged with an engaging portion 671 (see FIG. 4) of the wafer holder 67 by expansion and contraction in the X-axis direction, and a motor 74 that advances and retracts the cylinder 72 in the Y-axis direction by belt driving, for example. I have. Then, the cylinder 72 is moved forward by the operation of the motor 74 to be positioned at the take-out position (position indicated by a solid line in FIG. 1), and the hook 73 is engaged with the wafer holder 67 by the reduction operation of the cylinder 72 at this take-out position. When the cylinder 72 is retracted to the drawing position (position indicated by the one-dot chain line in FIG. 1) by the reverse rotation operation of the motor 74, the wafer holder 67 is pulled out and transferred to the XY stage 65.
[0030]
The transfer stage 63 is used when the chip transfer device 64 is set to transfer by the posture maintenance transfer method and the bare chip 61 is transferred from the chip supply unit 62 while being face-up, A transfer portion that is moved up and down by a motor 631 is provided on the upper surface.
[0031]
The chip transfer device 64 includes a guide 81 extending in an oblique direction (R direction), a transfer head unit 82 as a first suction head supported so as to be moved and guided by the guide 81, and the guide 81. And a servo motor 85 which is fixed to the mounting portion 84 and rotates the ball screw shaft 83 at a fixed position, and is screwed onto the ball screw shaft 83. The nut portion 86 and the transfer head unit 82 are fixed. Then, by the forward / reverse rotation operation of the servo motor 85, the transfer head unit 82 has a pickup position of the bare chip 61 (a position indicated by a solid line in FIG. 1) and a delivery position (a position indicated by an alternate long and short dash line in the same figure). You can move forward and backward in the diagonal direction.
[0032]
As shown in detail in FIG. 3, the transfer head unit 82 includes a base 822 fixed to the nut portion 86 via a bracket 821, a lift motor 823 held by the base 822, a chip size, and the like. Alternatively, a plurality of types of suction nozzles 824, 825, and 826 serving as head units (three types in the example shown below; three types will be described below) corresponding to the types, and the three types of suction nozzles 824 by rotation around the horizontal axis H1. , 825, and 826, a posture changing motor 827 that also serves as a rotation driving unit that performs nozzle replacement and a reversing driving unit that vertically inverts, and a negative pressure for vacuum suction and a positive for separation to each of the suction nozzles 824, 825, and 826. And a negative pressure supplier 828 for performing pressure switching supply and the like. The posture changing motor 827 and the negative pressure supplier 828 are integrally held by a support 829, and the support 829 can be moved in the vertical direction (Z-axis direction) by a guide (not shown) of the base 822. It is guided to.
[0033]
The support 829 includes an arm 830 that protrudes toward the base 822, and the arm 830 is moved up and down by a rotational drive around a horizontal axis H2 of a cam 831 fixed to the operating shaft of the lifting motor 823. As a result, the support 829 and the suction nozzles 824, 825, and 826 held by the support 829 are moved up and down. The suction nozzles 824, 825, and 826 are individually held by three holding arms 833, 833,... Projecting in a radial direction from a rotary shaft 832 disposed along the horizontal axis H1, and the rotary shaft 832 is held. Is rotated by receiving the rotational driving force of the attitude converting motor 827 through a belt 834 spanned between a pair of pulleys. Then, for example, if the rotation amount control of the attitude converting motor 827 is operated to rotate 180 degrees from the state of FIG. 3, the suction nozzle 824 rotates 180 degrees around the horizontal axis H1 and is turned upside down and rotated 60 degrees. The other suction nozzle 825 is directed downward from the suction nozzle 824 so that the suction nozzle is replaced.
[0034]
FIG. 4 is a partially omitted perspective view showing the arrangement in the chip supply unit 62. In the figure, 91 is an optical system (camera) for chip recognition, and 92 is an ejector means.
[0035]
The camera 91 and an ejector pin 931 or 941 (described later) of the ejector means 92 are disposed at a pickup position P sandwiching the pickup-target bare chip 61 on the wafer holder 67 from above and below, and the XY stage 65 is positioned relative to the pickup position P. Bare chips 61 are sequentially positioned and picked up by movement adjustment.
[0036]
As shown in FIG. 5, the ejector means 92 includes a plurality of types (two types in the illustrated example) of ejector pin units 93 and 94 according to the bare chip size, and a bracket for holding these two types of ejector pin units 93 and 94. 95 (see FIG. 4), and a conversion drive unit (not shown) that selectively converts the two types of ejector pin units 93 and 94 to the pickup position P by rotating the bracket 95 about the horizontal axis H3, And a push-up mechanism 96 that pushes upward the ejector pin of the ejector pin unit at the pickup position. The push-up mechanism 96 rotates the push-up portion 961 via, for example, a link mechanism, and pushes the ejector pin upward by causing the push-up portion 961 to collide with the base end side of the ejector pin.
[0037]
Each of the ejector pin units 93 and 94 includes an ejector pin 931 or 941 and housings 932 and 942 that hold the ejector pins 931 and 941 so as to be able to advance and retreat. By operating the push-up mechanism 96 in a state where the back surface of the wafer sheet 69 (see FIG. 4) is vacuum-sucked from the suction hole, the wafer chip 69 is pushed up and bent by the ejector pins 931 and 941, and the bare chip 61 is pushed up. As a result, the contact portion between the wafer sheet 69 and the bare chip 61 is reduced.
[0038]
One ejector pin unit 93 includes three ejector pins 931, 931, and 931 for a relatively large size bare chip 61, and the other ejector pin unit 94 targets a relatively small size bare chip 61. One ejector pin 941 is provided. 4 shows the ejector pin unit 93 positioned at the pickup position P, and FIG. 5 shows the ejector pin unit 94 positioned at the pickup position P. The number of ejector pins 931 in one ejector pin unit 93 is not limited to three, and may be two or four or more.
[0039]
Hereinafter, the transfer of the bare chip 4 and the mounting on the substrate 3 will be described. In FIG. 4, the bare chip 61 to be picked up is positioned at the pickup position P by horizontal movement in the X axis direction and the Y axis direction by the XY stage 65. When it is determined that the chip is recognized as good by the camera 91 in this state, the transfer head unit 82 is moved horizontally in the R-axis direction, and the suction nozzle 824 is set at the pickup position P between the top and bottom of the bare chip 61 and the camera 91. Will be. Then, the suction nozzle 824 is lowered by driving the lifting motor 823, and the bare chip 61 is vacuum-sucked by the suction nozzle 824 almost in synchronization with the push-up of the bare chip 61 by the ejector pin 931.
[0040]
Next, after the suction nozzle 824 is raised, in the case of transfer by the posture maintenance method, the servo motor 85 (see FIG. 1) is driven to transfer the transfer head unit 82 as it is to the delivery position in the R-axis direction. . The bare chip 61 sucked by the lifting and lowering operation of the suction nozzle 824 at this delivery position is placed on the transfer stage 63. Then, the mounter head unit 5 is horizontally moved to the delivery position by driving the servo motors 10 and 12, and the bare chip 61 on the transfer stage 63 is vacuum-sucked by moving up and down at the delivery position. The bare chip 61 in the up state is transferred to the substrate 3 by the mounter head unit 5 and mounted in the face up state. When the bare chip 61 is transferred from the transfer head unit 82 to the mounter head unit 5, the transfer stage 65 is appropriately moved up and down to adjust the vertical position.
[0041]
On the other hand, in the case of transfer by the posture inversion method, the bare chip 61 that has been sucked by rotating the suction nozzle 824 by 180 degrees by driving the posture conversion motor 827 during the transfer to the delivery position of the transfer head unit 82. The posture is turned upside down and face down. When the transfer head unit 82 reaches the delivery position, the mounter head unit 5 moves to the delivery position and vacuum-sucks the bare chip 61 in the face-down state. The bare chip 61 is transferred to the substrate 3 by the mounter head unit 5 and mounted in a face-down state.
[0042]
Further, for example, the mounting operation as the entire composite mounting machine is performed as follows. That is, after a printed circuit board P to be mounted is first carried by the conveyor 2 and stopped at a predetermined mounting work position, there is a component to be mounted based on the component mounting data on the printed circuit board P stored in advance. It is determined. When the component to be mounted is a bare chip, the bare chip supplied from the bare chip supply unit 62 is mounted as described above. On the other hand, when the component to be mounted is a completed electronic component, the component sucked from the component supply unit 4 by the mounter head unit 5 is mounted on the printed board P.
[0043]
In addition, this invention is not limited to the said embodiment, Other various embodiment is included. For example, in the above embodiment, the suction nozzle 824 of the transfer unit 82 is turned upside down in the middle of the transfer from the pickup position to the delivery position. The upside down may be performed after the pickup at the pickup position or may be performed after reaching the delivery position.
[0044]
【The invention's effect】
As described above, the chip transfer device of the present invention includes the first suction head that sucks and transfers the chip from the chip supply unit, the reverse drive unit that allows the first suction head to be turned upside down, and the non-reverse drive. A transfer stage for mounting a chip separated from the first suction head in a state, and a second suction head for selectively sucking a chip from either the first suction head or the transfer stage in an inverted state Therefore, it is possible to execute both the posture maintenance transfer method and the posture conversion transfer method with the same device, and whether the mounting posture on the board is a face-up state or a face-down state. Regardless of how it can be shared by a single device. As a result, it is possible to obtain great effects such as a reduction in equipment cost, a reduction in manufacturing cost of semiconductor products, and a reduction in equipment space.
[0045]
Further, the chip supply unit is provided with ejector means for pushing up the chip, and the ejector means includes a plurality of types of ejector pin units corresponding to the chip size, and a conversion driving unit that mutually converts the positions of the plurality of types of ejector pin units by rotation. With this configuration, it is possible to convert to an appropriate ejector pin unit according to the chip size, and it is possible to more reliably peel off the chip from the wafer sheet.
[0046]
In addition, the first suction head includes a central shaft body arranged in the horizontal direction, a plurality of head portions arranged so as to protrude radially from the central shaft body, and the central shaft body around the central axis. By rotating the actuator to a size, it is possible to reduce the size of the chip supplied by the chip supply unit by including a rotation drive unit that positions the specific head unit selected according to the chip size from the plurality of head units downward. Accordingly, it can be converted into an appropriate specific head portion, and suction and transfer by the first suction head can be performed more reliably.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an overall plan view when an embodiment of the present invention is applied to a composite mounting machine.
FIG. 2 is an explanatory side view in which a part of the mounter head unit is omitted.
FIG. 3 is a perspective view in which a part of a transfer head unit is omitted.
FIG. 4 is a partially omitted perspective view showing an arrangement in a chip supply unit.
FIG. 5 is a cross-sectional explanatory view showing the operating principle of the ejector means.
[Explanation of symbols]
20 Second suction head
61 Bare chip
62 Chip supply unit
63 Transfer stage
67 Wafer holder
82 Transfer head unit (first suction head)
92 Ejector means
93, 94 Ejector pin unit
824-826 suction nozzle
827 Attitude conversion motor (reverse drive unit, rotation drive unit)
832 Rotating shaft (center shaft)

Claims (3)

A posture maintenance transfer method for transferring a chip from the chip supply unit while maintaining a supply posture in the chip supply unit, and a posture reversal transfer method for transferring a chip from the chip supply unit with an upside down operation from the supply posture. A chip transfer device that selectively executes transfer of chips by both transfer methods, a first suction head that sucks chips from the chip supply unit and transfers them horizontally, and a first suction head that sucks chips. A reversing drive unit that selectively reverses the suction head by rotating around the horizontal axis and a chip that is placed on the first suction head in a non-reversed drive state while being spaced apart from the first suction head. A mounting stage by selectively sucking a chip from any one of the mounting stage, the first suction head inverted upside down by the inversion driving unit, and the transfer stage; Chip transfer device, characterized in that a second suction head for transferring up. The chip supply unit includes ejector means that pushes the chip upward from the lower position when the chip is sucked by the first suction head. The ejector means includes a plurality of types of ejector pin units corresponding to the chip size, and a rotation The chip transfer device according to claim 1, further comprising: a conversion drive unit that converts the positions of the plurality of types of ejector pin units relative to each other. The first suction head includes a central shaft body disposed in the horizontal direction, a plurality of head portions disposed so as to project radially from the central shaft body, and the central shaft body rotating about the central axis. The chip transfer device according to claim 1, further comprising: a rotation drive unit that positions the specific head unit selected from the plurality of head units according to the chip size downward.

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