JP2019004114A - Ball supply device and ball loading device - Google Patents

Abstract

To provide a ball supply device and a ball loading device capable of supplying balls to the ball loading device without stopping the ball loading device, and capable of loading balls on a board without damage and without excess or shortage.SOLUTION: A ball supply device 10 placed at a position separated from a ball loading device 50 includes a ball tank 12, a ball supply nozzle 13 for supplying balls 11 to ball throwing-in head units 64A, 64B, and a ball transfer tube 14 for connecting the ball tank 12 and the ball supply nozzle 13, pumps the balls 11 from the ball tank 12 to the ball supply nozzle 13 by compressed gas and decompresses a ball transfer path to normal pressure at highspeed when stopping the pumping. The ball supply device 10 pumps a specified quantity of balls 11 based on a ball supply order from the ball throwing-in head units 64A, 64B, and the ball loading device is supplied with balls from the ball supply device 10.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a ball supply device and a ball mounting device for supplying a ball from the ball supply device.

  Conventionally, there is a ball mounting device as means for mounting a conductive ball on an electrode of a ball mounting object such as a printed wiring board or a silicon wafer, and there is a ball supply device for supplying the ball to the ball mounting device. For example, in Patent Document 1, a ball tank that stores balls and a ball holding unit that stores a predetermined amount of balls are arranged in a ball mounting device, and the ball tank and the ball holding unit are connected by a ball transfer passage. There is disclosed a ball supply device for discharging a ball onto a ball mounted object from a ball discharge passage connected to the ball holding portion. In this ball supply device, the vacuum suction means is turned ON and the ball is vacuum sucked from the ball tank and stored in the ball holding part, and the vacuum suction means is turned OFF and the ball is discharged from the ball holding part onto the ball mounted object. That's it.

JP 2011-254011 A

  However, in the ball supply device described in Patent Document 1, since the mounted object is disposed immediately above the ball mounting device, the ball mounting device must be stopped when the ball is supplied to the ball tank. In addition, there is a limit to the amount of balls that can be stored in the ball tank, and there is a problem that the ball mounting measures must be stopped frequently to replenish the balls. In addition, since the ball tank is arranged directly above the object to be loaded with the ball, the ball must be replenished in a narrow space, so that the workability is poor, and when the ball is replenished, There is a problem that balls may be spilled, and foreign balls spilled when the ball mounting device is operated before the current ball mounting are mixed.

  In addition, the ball supply device described in Patent Document 1 supplies the ball with the suction state turned on and discharges the ball with the suction state turned off. However, even if the suction state is turned off, the entire ball transfer path remains. Since the ball is not instantaneously turned off (ball supply is stopped), there is a risk of excessive or insufficient balls being supplied to the mounted object.

  In addition, a mechanical shutter is installed at the tip of the ball discharge passage to block the ball discharge to the ball mounted object, and the ball surface is damaged by pinching or rubbing the ball with the shutter when driving the shutter. There is a fatal problem of giving.

  Therefore, the present invention has been made to solve at least one of these problems, and it is possible to supply a ball to the ball mounting device without stopping the ball mounting device, and damage the ball surface. Therefore, an object of the present invention is to provide a ball supply device and a ball mounting device capable of mounting a ball on the ball mounted object without excess or deficiency.

[1] A ball supply device according to the present invention is a ball supply device for supplying a ball to a ball mounting device, the ball tank being disposed at a position apart from the ball mounting device in a plane and storing the ball, A ball supply nozzle for supplying the ball to the ball transfer head unit of the ball mounting device, a ball transfer tube for connecting the ball tank and the ball supply nozzle, and the compressed gas from the ball tank to the ball supply nozzle. A pressure air system for pressure-feeding the ball and a pressure air destruction system for reducing the ball transfer path from the ball tank to the ball supply nozzle to normal pressure, and based on a ball supply command from the ball transfer head unit A predetermined amount of the ball is pumped to the ball transfer head unit.

  According to the ball supply device of the present invention, since the ball pressure feeding from the ball supply device to the ball mounting device is started based on the ball supply command from the ball mounting device, the ball mounting device can be transferred to the ball mounting device without stopping. Ball supply is possible. In addition, if the ball tank is arranged at a position away from the ball mounting device in the plane direction, the ball tank can be easily replenished, and when the ball is replenished, the ball falls on the ball mounted object or the ball mounting device. Therefore, it is possible to prevent mixing of different kinds of balls that have been spilled when the ball mounting apparatus was operated. Furthermore, in transferring the ball, the ball is pumped by the compression system, and the pumping of the ball is instantaneously stopped by the pressurized air destruction system, so that the ball can be supplied to the ball mounting device without excess or deficiency. Further, since the mechanical shutter is not used, the ball surface is not damaged. Here, the ball mounted object is, for example, a printed wiring board or a silicon wafer on which electrodes are formed.

[2] In the ball supply device of the present invention, the drive of the pressure system is stopped based on a ball supply stop command from the ball transfer head unit, and the drive of the pressure destruction system is started and vacuum pressure is used. It is preferable to return the ball transfer path to normal pressure at high speed.

  In this way, the ball transfer is stopped by stopping the pressure transfer of the ball and returning the ball transfer path from the ball tank to the ball mounting device to normal pressure (atmospheric pressure when the device is operating) at high speed. This makes it possible to supply the ball with no excess or deficiency to the ball mounting device.

[3] In the ball supply apparatus of the present invention, the compressed gas is preferably an inert gas having a pressure of normal pressure or higher and 0.2 MPa or lower.

  If at least the inside of the ball tank is made higher than the normal pressure, the ball in the ball tank can be pumped to the ball transfer path. If the pressure is 0.2 Mpa or less, which is approximately twice the normal pressure, Will not damage. Further, when an inert gas such as nitrogen gas is used as the compressed gas, it is possible to suppress the formation of an oxide film on the surface of the ball, which is an electrical joining means between the substrate and the electronic component.

[4] In the ball supply device of the present invention, it is preferable that the ball transfer tube has flexibility and flexibility, has an inner diameter of 2 mm to 5 mm, and a bending radius of 20 mm or more.

  The ball transfer tube is easy to bend because it has flexibility and flexibility, and the ball tank can be freely selected in both the plane direction and the height direction with respect to the ball mounting device. Ball replenishment work becomes easier. In addition, the ball tank can be enlarged. Furthermore, if the inner diameter of the ball transfer tube is 2 mm to 5 mm and the radius of curvature is 20 mm or more, it is possible to prevent the ball from being clogged at the bent position of the ball transfer tube or from being hit and damaged.

[5] In the ball supply device of the present invention, it is preferable that the surface resistance of the contact surface of the ball transfer tube with the ball is 1 × 10 ⁻⁹ Ω or less.

  The ball transfer tube has flexibility and flexibility. As a material of such a tube, for example, it is made of resin, and since the resin tube has an insulating property and tends to be charged with static electricity when it comes into contact with the ball, the balls are adsorbed, or the ball transfer tube and the ball May be adsorbed and the transfer of the ball may be delayed. Therefore, for example, if the surface resistance is minimized by forming a conductive film on the inner surface of the ball transfer tube, the generation of static electricity can be suppressed, and the ball can be transferred smoothly.

[6] A ball mounting device according to the present invention is a ball mounting device for mounting a ball supplied from a ball supply device on a ball mounted object, and a ball transfer head that transfers a predetermined amount of the ball into the ball mounted object. A ball holding unit that stores the ball supplied from the ball supply device; and a ball discharge unit that communicates with the ball holding unit and discharges the ball to the mounted object. A ball detection lower limit sensor having a passage and detecting a lower limit amount of the ball stored in the ball holding unit and transmitting a ball supply command to the ball supply device; and It has a ball detection upper limit sensor which detects an upper limit amount and transmits a ball supply stop command to the ball supply device.

  The ball detection upper limit sensor detects the amount of balls to be mounted on the ball mounted object, and the ball detection lower limit sensor detects that the necessary amount of balls to be mounted on the ball mounted object is insufficient. When the ball mounting device detects that a ball necessary for mounting the ball is supplied to the ball holding portion, the ball mounting device stops the pumping of the ball and detects that the amount of balls to be mounted on the ball holding portion is insufficient. The apparatus is started to supply balls. Therefore, the ball can be supplied to the ball mounting device without stopping the ball mounting device. In addition, since there is no mechanical shutter in the ball discharge passage, the ball surface is not damaged.

It is a longitudinal section showing ball supply device 10 concerning an embodiment. It is a top view which shows one Example of the ball mounting apparatus 50 which concerns on embodiment. It is a top view which shows the ball transfer apparatus 57 which concerns on embodiment. 5 is a plan view showing an example when the substrate 51 according to the embodiment is a silicon wafer 80. FIG. It is a front view showing ball transfer head unit 64A concerning an embodiment. It is explanatory drawing which shows a mode that the ball | bowl 11 which concerns on embodiment is mounted on the silicon wafer 80. FIG. It is process flow explanatory drawing which shows the main processes of the ball mounting method which concerns on embodiment. It is process flow explanatory drawing which shows the main processes of the ball | bowl supply method during the ball mounting continuation concerning embodiment.

  Hereinafter, a ball supply device 10 and a ball mounting device 50 according to an embodiment of the present invention will be described with reference to FIGS.

[Configuration of Ball Supply Device 10]
FIG. 1 is a longitudinal sectional view showing the ball supply device 10. FIG. 1 shows a state immediately after the supply of the ball 11 is stopped. The ball supply device 10 connects a ball tank 12 that stores a large amount of balls 11, a ball supply nozzle 13, a ball tank 12 and a ball supply nozzle 13, and connects the ball 11 stored in the ball tank 12 to the ball supply nozzle. And a ball transfer tube 14 to be transferred to 13. The ball 11 has conductivity, such as a solder ball, a metal ball, a conductive plastic ball, and a conductive ceramic ball, and has a spherical shape. In addition to the true sphere, the spherical shape includes polygons and particles having irregularities on the surface.

  The ball supply nozzle 13 is a so-called ball hopper in which a lower inner portion is a nozzle portion 15 having a cross-sectional area narrowed in a funnel shape. The nozzle unit 15 is provided with a ball insertion opening 92 of a ball holding unit 88 provided in the ball mounting device 50 when the ball supply device 10 supplies the ball 11 to a ball mounting device 50 (see FIGS. 3 and 5) described later. Communicate with. The volume of the ball tank 12 is much larger than the volume of the ball holding part 88.

  The ball transfer tube 14 is a resin tube that is flexible and flexible and can be bent freely. The ball transfer tube 14 preferably has an inner diameter of 2 mm to 5 mm and a radius R of the bent portion of 20 mm or more in order to transfer the ball 11 without resistance. The ball transfer tube 14 may have a length of about 1 m, for example, in order to arrange the ball tank 12 at a position away from the ball mounting device 50 in the plane direction. One end of the ball transfer tube 14 extends into the ball supply nozzle 13, and a part on the lower side in the figure is a protruding portion 16 projecting obliquely upward. The protruding portion 16 is provided to prevent the ball 11 that should remain in the ball transfer tube 14 from falling into the ball holding portion 88 when the supply of the ball from the ball tank 12 is stopped.

  In the ball tank 12, a ball detection lower limit side sensor 20 is disposed on the bottom side, and a stored ball detection lower limit sensor 21 is disposed above the ball detection lower limit side sensor 20. Both the ball detection lowest limit side sensor 20 and the stored ball detection lower limit sensor 21 are optical sensors (for example, LED sensors) provided with a light emitting element and a light receiving element. The ball detection lowest limit side sensor 20 has a function of notifying the operator that the amount of storage of the ball 11 in the ball tank 12 has reached a limit value for stopping the ball mounting device 50. When a detection signal is transmitted from the ball detection lowest limit side sensor 20, the ball mounting device 50 is stopped. However, the flux printing device 56 (see FIG. 2) operates until the flux printing of one substrate 518 (or the silicon wafer 80) is completed when the flux printing is in progress.

  On the other hand, the storage ball detection lower limit sensor 21 has a function of notifying the operator of the timing at which the ball storage amount in the ball tank 12 should replenish the ball 11 to the ball tank 12. In this case, the ball mounting device 50 may not be stopped. That is, the operation of the ball mounting device 50 can be continued until the ball detection lowest limit sensor detects it. Note that one ball detection lower limit sensor may be disposed at an intermediate position between the ball detection lower limit side sensor 20 and the stored ball detection lower limit sensor 21.

An openable / closable tank lid 22 is provided above the ball tank 12. When the ball detection lower limit side sensor 20 or the stored ball detection lower limit sensor 21 notifies the addition of the ball 11, the operator opens the tank lid 22 and throws the ball 11 into the ball tank 12, and then the tank lid 22. To seal. A conductive film 23 is formed on the inner surface of the ball transfer tube 14 (the surface with which the ball 11 is in contact). The surface resistance of the conductive film 23 is preferably 1 × 10 ⁻⁹ Ω or less. The balls 11 may be charged with static electricity generated while being transferred to the inside of the ball transfer tube 14, and the balls may adsorb each other. However, the formation of the conductive film 23 can prevent the balls 11 from being charged. . In the same sense, when the ball transfer path such as the ball tank 12 with which the ball 11 contacts, the ball supply nozzle 13, the ball holding portion 88 and the ball discharge passage 94 (see FIG. 5) is a non-conductive material, More preferably, the conductive film 23 is formed on the inner surface.

  A pipe 24 communicating with the ball tank 12 is connected to the tank lid 22. A first opening / closing valve 25 for opening and closing the pipe 24 is disposed in the vicinity of the ball tank 12 of the pipe 24. The first opening / closing valve 25 may be a manual valve or an electromagnetic valve, and is opened when the ball supply device 10 is operated, and is closed when the ball supply device 10 is stopped. That is, it is released when the ball mounting apparatus 50 is operated, and is closed when the operation of the ball mounting apparatus 50 is stopped.

  A second opening / closing valve 26 for opening and closing the piping 24 is disposed above the first opening / closing valve 25 of the piping 24. When the ball supply device 10 transfers the ball, the inert gas compressed by releasing the second opening / closing valve 26 is sent into the ball tank 12 from the pipe 24. Since the cross-sectional area of the ball transfer tube 14 is abruptly reduced with respect to the ball tank 12, the ball 11 in the ball tank 12 does not naturally fall onto the ball transfer tube 14 unless compressed gas is supplied. . Therefore, by sending a compressed inert gas into the ball tank 12, the pressure inside the ball tank 12 is increased, and the ball 11 is pumped into the ball transfer tube 14 and transferred to the ball holder 88 via the ball supply nozzle 13. Can do. The downstream side of the ball supply nozzle 13 is atmospheric pressure. Nitrogen gas is used as the inert gas, and the pressure is preferably normal pressure (atmospheric pressure) or higher and 0.2 Mpa or lower. Nitrogen gas is used to prevent the formation of an oxide film on the ball surface.

  A branch pipe 27 is connected between the first on-off valve 25 and the second on-off valve 26 of the pipe 24. The branch pipe 27 is for depressurizing the inside of the ball tank 12, a third opening / closing valve 28 is disposed, and a filter 29 is disposed between the third opening / closing valve 28 and the pipe 24. . When the supply of the ball is stopped, the second opening / closing valve 26 is closed. However, since the inside of the ball tank 12 is in a high pressure state, if the ball 11 remains in the ball tank 12 and the ball transfer tube 14, the ball 11 It will be pumped to the mounting device 50. Therefore, if the third on-off valve 28 is released and vacuum suction is performed, the ball transfer path from the ball tank 12 to the ball supply nozzle 13 is reduced to normal pressure at a high speed, and the ball transfer to the ball mounting device 50 is momentarily stopped. it can. The branch pipe 27 is connected to a vacuum suction device (not shown). The filter 29 is provided to prevent the third on-off valve 28 from being clogged due to the ball 11 being sucked into the branch pipe 27 when the pressure in the ball tank 12 is reduced. The second on-off valve 26 and the third on-off valve 28 are both electromagnetic on-off valves that can be opened and closed instantaneously.

  Note that a upstream side of the pipe 24 (outside the building) has a compressed inert gas supply source for supplying a compressed inert gas into the ball tank 12, for example, a nitrogen gas cylinder (not shown). The piping 24, the second on-off valve 26, and the control unit (not shown) for feeding the compressed inert gas are used as a pressurized air system. On the other hand, the branch pipe 27, the third on-off valve 28, and the control unit (not shown) of the system for reducing the pressure in the ball tank 12 are used as a pressure air destruction system. The pressure destruction system has a function of returning the ball transfer path to normal pressure at high speed using vacuum pressure. That is, by switching from the pressure system to the pressure destruction system at high speed, it is possible to instantaneously switch between supply and stop of supply of the ball 11 to the ball mounting device 50.

  The ball supply device 10 operates in conjunction with the ball mounting device 50. Next, the configuration of the ball mounting device 50 and the ball transfer operation will be described with reference to FIGS.

[Configuration of Ball Mounting Device 50]
FIG. 2 is a plan view showing an embodiment of the ball mounting apparatus 50. As shown in FIG. The ball mounting device 50 includes a substrate stocker 52 that stocks the substrate 51 on which the ball 11 is to be mounted, a substrate transport robot 55 that transports the substrate 51 to the pre-aligner 53, and transports the substrate 51 from the pre-aligner 53 to the stage 54, A flux printing device 56 that prints the flux 40 (see FIG. 6) on the substrate 51 and a ball transfer device 57 that transfers the balls 11 to the substrate 51 on which the flack 40 is printed are provided. Further, the ball mounting device 50 includes an inspection device 58 that inspects the mounting state of the ball 11 and a cleaning device 59 that removes excess flux 40 adhering to the back surface of the print mask 41.

  The substrate 51 is a plate-like or film-like member for fixing and wiring the electronic component, and is mounted with an electronic component such as a semiconductor integrated circuit, or a wafer such as a silicon semiconductor substrate or a compound semiconductor substrate. including. The flux 40 is for increasing the wettability of solder or the like, and becomes a solder paste when the ball 11 is a gold ball or a copper ball, for example. The flux 40 may be either rosin or water-soluble, but a flux having a high adhesive strength is selected so that the transferred ball 11 does not move.

  The substrate stocker 52 includes a load port and an unload port (not shown) (sometimes referred to as a load port when the target substrate is a wafer). The substrate transfer robot 55 takes out the substrate 51 from the load port and removes the pre-aligner 53. Transport to. When the substrate 51 is a wafer, the pre-aligner 53 transports the substrate 51 corrected for both the center position of the substrate 51 and the notch direction formed on the outer periphery of the substrate 51 to the stage 54. Thereafter, the substrate transfer robot 55 returns to the standby position. The substrate 51 placed on the substrate placing table 60 of the stage 54 is adsorbed under reduced pressure, and the warpage is corrected by pressing the substrate 51 with the substrate correcting device 61.

  The substrate correcting device 61 is for correcting the warp of the substrate 51 by pressing the outer peripheral portion of the substrate 51 with eight pressing members, and is particularly effective for a printed wiring board having a relatively large warp. These pressing members are attached to the lower part of the cylinder rod of the air cylinder via a jig. When the substrate 51 is placed on the stage 54 by the substrate transfer robot 55, the stage 54 on which the substrate 51 is placed is mounted. When moving, and when the substrate transport robot 55 removes the substrate 51 from the stage 54, it can escape upward. The position of the stage 54 corresponding to the substrate correction device 61 is a position where the substrate 51 is placed on the stage 54 and a position where it is removed.

  The stage 54 includes an X table 62, a Y table 63, a Z table (not shown), and a θ table (not shown) as mechanisms for moving the substrate mounting table 60. The stage 54 can transport the substrate 51 below the flux printing device 56 and the ball transfer device 57, and the X table 62 moves the stage 54 from the substrate correction device 61, the flux printing device 56, and the ball transfer. It reciprocates between the devices 57. In the case where the substrate 51 is a tape-like long object that is difficult to rotate, the θ table is preferably disposed in the ball transfer head units 64A and 64B.

  After moving the stage 54 on which the substrate 51 is placed on the X-axis table 62 below the flux printing device 56, the flux 40 (see FIG. 6) is printed on the substrate 51. In addition, when the flux 40 is previously printed on the substrate 51 in another place or another process, this printing process is skipped. The cleaning device 59 is a device that removes the flux 40 adhering to the back surface of the printing mask 41 using a sheet or roll containing a solvent.

  The substrate 51 on which the flux 40 is printed moves on the X-axis table 62 below the ball transfer device 57 while being placed on the stage 54. The stage 54 aligns an electrode 83 (see FIG. 6) formed on the substrate 51 and a mask opening 65a (see FIG. 6) formed in the transfer mask 65. Thereafter, the ball 11 supplied from the ball supply device 10 falls onto the transfer mask 65 via the pair of ball transfer head units 64A and 64B, and is moved in the plane direction by the ball transfer head units 64A and 64B to be a substrate. 51 is transferred onto the electrode 83.

  The substrate 51 on which the ball 11 is mounted returns to the position where the substrate 51 is placed and removed, the suction is released, and the substrate 51 is transferred to the inspection device 58 by the substrate transfer robot 55. After the inspection of the mounting error of the balls 11 and the surplus balls is completed, the substrate 51 is stored in the substrate stocker 52 by the substrate transport robot 55. When ball mounting mistakes are continuously small, the inspection may be omitted and the substrate 51 on which the balls 11 are mounted may be sent to the reflow furnace.

  On the other hand, the inspection device 58 may be installed outside the ball mounting device 50 in a configuration integrated with a repair device that corrects mounting defects. The substrate 51 accommodated in the substrate stocker 52 is sent to a reflow apparatus (not shown) to form bumps. The substrate 51 on which the bumps are formed is processed in the next process or is cut into individual chips by a cutting machine.

  FIG. 3 is a plan view showing the ball transfer device 57 and schematically shows the ball mounting device 10. The ball transfer device 57 moves the mask frame 70 that holds the transfer mask 65, the ball transfer head units 64A and 64B that discharge the ball 11 onto the transfer mask 65, and the ball transfer head units 64A and 64B in the Y-axis direction. Y-axis drive units 72A and 72B for transfer heads, X-axis drive units 73 for transfer heads that move the ball transfer head units 64A and 64B in the X-axis direction, and head sliders 74 that support the ball transfer head units 64A and 64B. And have. The ball transfer device 57 has three cameras 75, 75 and 76. An area where the mask opening 65a (see FIG. 6) into which the ball 11 is transferred is formed (shown by a dotted line in FIG. 3) is referred to as an opening forming area 77, and the arrangement of the mask opening 65a may be referred to as an opening pattern.

  The cameras 75 and 75 are arranged at positions where a position mark (not shown) of the substrate 51 that has moved enters the field of view. The cameras 75 and 75 are a pair of cameras attached to the gantry 78 of the ball transfer device 57, and are used to recognize the position mark (not shown) of the substrate 51 and calculate the position and angle of the substrate 51. . The role of the pre-aligner 53 is to enable the cameras 75 and 75 to capture the position mark of the substrate 51.

  On the other hand, the camera 76 is a camera that moves together with the ball transfer head units 64A and 64B. The displacement of the mask opening 65a and the electrode 83 (see FIG. 6) and the position mark on the upper surface of the transfer mask 65 are recorded on the transfer mask 65. Used for image recognition from above. The same alignment can be performed when the flux 40 is printed. The transfer head Y-axis drive units 72 </ b> A and 72 </ b> B are fixed on a mount 78. On the other hand, the mask frame 70 is detachably attached to the gantry 78 via an attachment jig (not shown).

  The ball transfer head units 64A and 64B are movably connected to the transfer head X-axis drive unit 73 via the head slider 74, and the transfer head X-axis drive unit 73 is further connected to the transfer head Y-axis drive unit 73. And movably connected. The head slider 74 is provided with a Z-axis drive unit (not shown). With such a drive mechanism, the ball transfer head units 64A and 64B can be integrated and can move horizontally and vertically on the transfer mask 65.

  FIG. 3 shows an example in which the ball transfer head units 64A and 64B are arranged in the X-axis direction. However, the ball transfer head units 64A and 64B are arranged in the Y-axis direction, the shape of the ball transfer heads 64A and 64B is increased to one, and vice versa. In addition, three or more ball transfer head units can be arranged in one or a plurality of rows.

  The ball supply device 10 is connected to the ball transfer device 57 via the ball supply nozzles 13 and 13. FIG. 3 shows a state where the supply of balls to the ball transfer head units 64A and 64B is stopped. That is, the ball supply nozzles 13 and 13 are fixed at positions away from the ball transfer head units 64A and 64B, which are ball supply targets. The ball transfer head units 64A and 64B are moved to below the ball supply nozzles 13 and 13 by the transfer head Y-axis drive units 72A and 72B (in the direction of the arrow in the figure), and the balls 11 are moved from the ball supply nozzles 13 and 13 by a certain amount. receive. The ball supply device 10 is equipped in accordance with the number of ball transfer heads. Since the embodiment shown in FIG. 3 has two ball transfer head units 64A and 64B, two ball supply devices 10 are provided. The ball supply nozzles 13 and 13 are connected to the ball tanks 12 and 12 via ball transfer tubes 14 and 14, respectively.

  4 is a plan view showing an example when the substrate 51 is a silicon wafer 80, FIG. 4 (a) is a plan view of the silicon wafer 80, and FIG. 4 (b) is a dotted line shown in FIG. 4 (a). FIG. 6 is an enlarged view showing a part of an electrode formation region (semiconductor integrated circuit formation region) 81 surrounded by A. The semiconductor integrated circuit 82 is surrounded by four scribe lines 84 provided between the groups of electrodes 83, and the scribe lines 84 are cut to form individual semiconductor integrated circuit chips. This cutting is performed after the silicon wafer 80 on which the balls 11 are mounted is reflowed in a reflow furnace or at the end of the mounting process.

  The electrode 83 is a rewired electrode. The pitch of the rewiring electrodes 83 is approximately 50 to 400 μm. FIG. 4 is a diagram for explaining the electrode 83 formed on the silicon wafer 80 and the arrangement of the electrode formation region 81 where the electrode 83 is formed. The shape is different from the real one and is not even more similar.

  The silicon wafer 80 has a diameter of 300 mm or 200 mm. The arrangement of the electrodes 83 formed in the polygonal electrode formation region 81 surrounded by the dotted line is referred to as an electrode pattern. The pattern of the mask opening 65 a formed in the transfer mask 65 is a pattern similar to the electrode pattern formed in the silicon wafer 80.

  FIG. 5 is a front view showing the ball transfer head unit 64A. FIG. 5A shows the state after the ball 11 is discharged onto the transfer mask 65, and FIG. 5B shows the way in which the ball 11 is being supplied to the ball holding unit 88. Since the ball transfer head unit 64B has the same configuration as the ball transfer head unit 64A, the ball transfer head unit 64A will be described as an example. The ball transfer head unit 64A includes a ball holding unit 88, a ball fixed amount supply device 89, a rotation motor 90, and a transfer head 91 that are arranged in series downward in the height direction by a ball transfer head unit mounting plate 87. It is supported. The ball holding portion 88 has a ball throwing opening 92 into which the ball 11 is thrown.

  The ball holding portion 88 and the ball fixed amount supply device 89 are connected by a connecting pipe 93, and the ball fixed amount supply device 89 and the transfer head 91 are connected by a ball discharge passage 94, and are inserted into the ball holding portion 88. The ball 11 thus dropped falls from the ball fixed amount supply device 89 through the ball discharge passage 94 onto the transfer mask 65. A binding linear member 95 is attached to the end face of the transfer head 91 on the transfer mask 65 side. The ball transfer head unit 64 </ b> A moves on the XY plane of the transfer mask 65 while rotating the binding linear member 95 to transfer the ball 11 onto the upper surface of the substrate 51 or the silicon wafer 80. The ball transfer will be described later with reference to FIG. Since the diameter of the ball 11 is as small as about 30 μm to 300 μm, it is shown enlarged, and the scale of FIG. 5 is not constant depending on the parts.

  The binding linear member 95 includes a fixing portion 98 having a substantially T-shaped side surface through which the ball discharge passage 95 passes in the center, and a plurality of linear members curved from the outer peripheral edge of the ball discharge passage 94 are radially spaced. It is fixed to become. In FIG. 5A, the binding linear member 95 is illustrated as being separated from the transfer mask 65. However, when the ball 11 is supplied onto the transfer mask 65, the binding linear member 95 is transferred. The ball 11 is lowered to a position in contact with the mask 65 so that the ball 11 does not dissipate to the outside of the binding linear member 95 at that time, and the ball 11 is also bound when the transfer head 91 is rotated in one direction. It is configured not to dissipate outside.

  The ball holding unit 88 includes a ball detection lower limit sensor 96 that detects the lower limit of the ball amount and a ball detection upper limit sensor 97 that detects the upper limit of the ball amount. The ball detection lower limit sensor 96 and the ball detection upper limit sensor 97 are optical sensors (for example, LED sensors) including a light emitting element and a light receiving element. The ball detection lower limit sensor 96 detects a state in which a predetermined amount of the balls 11 in the ball holding portion 88 can be discharged to the transfer mask 65, that is, the moment when the ball detection lower limit sensor 96 receives light, and supplies the ball supply device 10 with the ball. Send a command. The ball detection upper limit sensor 97 detects that a predetermined amount of the ball 11 has been supplied into the ball holding portion 88 and sends a signal for stopping the supply of the ball 11 to the ball supply device 10. The predetermined amount is, for example, the amount of one cycle of the ball mounting process (for one substrate 51 or silicon wafer 88). In FIG. 5A, the balls 11 stored on the bottom of the ball holding portion 88 (below the ball detection lower limit sensor 96) naturally fall onto the transfer mask 65 sequentially via the ball fixed amount supply device 89. .

  When the one-cycle ball mounting is completed, the ball transfer head unit 64A moves to the ball supply position directly below the ball supply nozzle 13 of the corresponding ball supply device 10, and as shown in FIG. It waits in the state which 92 and the nozzle part 15 of the ball supply nozzle 13 connected. Upon receiving the ball supply command from the ball detection lower limit sensor 96, the ball supply device 10 starts supplying the ball 11 from the ball tank 12 into the ball holding unit 88, and indicates that a predetermined amount of the ball 11 has been supplied. The ball supply is continued until the sensor 97 detects it, that is, until the moment when the ball detection upper limit sensor 97 is blocked from receiving light.

  FIG. 6 is an explanatory view showing a state in which the ball 11 is mounted on the silicon wafer 80. The ball 11 is pushed by the binding linear member 95 and moves on the transfer mask 65, spontaneously falls from the mask opening 65 a of the transfer mask 65, and is transferred onto the electrode 83 provided on the silicon wafer 80. The transfer mask 65 is formed with a mask opening 65a through which only one ball 11 passes. The diameter of the mask opening 65a depends on the diameter of the ball 11 and is about 10% larger than that. A protective film 80 a that protects the active surface of the semiconductor element is applied to the silicon wafer 80 so as to cover the outer periphery of the electrode 83. The flux 40 is printed on the surface of the electrode 83 that is not covered with the protective film 80a, but it is preferable that the flux 40 be printed so that the center is slightly raised in the hole of the protective film 80a.

  The thickness of the transfer mask 65 is set so that the apex of the ball 11 is below the upper surface of the transfer mask 65 so that the ball 11 is stably held in the mask opening 65a. The distance that the apex of the ball 11 is lowered from the upper surface of the transfer mask 65 is preferably about 5% of the ball diameter, and 2 to 10% is suitable. As the ball 11 sinks from the upper surface of the transfer mask 65 in this manner, the ball 11 transferred to the mask opening 65a by the binding linear member 95 is less likely to be scraped off. When the apex of the ball 11 is raised above the upper surface of the transfer mask 65, the ball 11 transferred into the mask opening 65a is easily scraped by the binding linear member 95.

  When the binding linear member 95 moves from the left to the right of the page, the ball 11 is pushed by the binding linear member 95 and is successively transferred into the mask opening 65a. The binding linear member 95 is thin and has a low rigidity of 30 μm to 100 μm for each of the wire rods. Therefore, the binding linear member 95 is slightly bent downward from the mask opening 65a and slightly enters the mask opening 65a. Accordingly, the transferred ball 11 is pushed into the flux 40 printed on the electrode 83 by the binding linear member 95, and is fixed to the extent that it does not move unless a large impact is given to the silicon wafer 80. The binding linear member 95 is preferably a little deformed to the extent that the ball 11 slid into the mask opening 65a is pressed from above. If the transferred ball 11 is not pushed into the flux 40, the ball 11 is likely to be detached from a predetermined position in a subsequent process (substrate conveyance, inspection, reflow, etc.).

[Ball mounting method and ball supply method]
FIG. 7 is a process flow explanatory diagram showing the main steps of the ball mounting method. First, it is assumed that the ball transfer head units 64A and 64B are moved to the arrangement positions of the ball supply nozzles 13 and 13 so that the balls can be supplied from the ball supply device 10 to the ball mounting device 50. When the operation of the ball mounting device 50 is started, the first opening / closing valve 25 is released. First, the ball 11 is supplied to the ball tank 12 (step S10). Ball replenishment is performed after the tank lid 22 of the ball tank 12 is released. After throwing in the ball, the ball lid 22 is closed to seal the ball tank 12.

  Subsequently, the second opening / closing valve 26 is released to send compressed inert gas into the ball tank 12, and the ball 11 stored in the ball tank 12 is sent to the ball holding portion 88 of the ball mounting device 50 ( Step S20). Then, it is determined whether or not the ball 11 has reached a predetermined amount by the ball detection upper limit sensor 97 provided in the ball holding portion 88 (step S30). When it is determined that the ball 11 has not reached the predetermined amount (NO), the pumping of the ball 11 is continued until the predetermined amount is reached. At the moment when it is detected that the ball 11 in the ball holding portion 88 has reached a predetermined amount (YES), the second on-off valve 26 is closed, and the third on-off valve 28 is released to stop the pressure feeding of the ball 11 ( Step S40), the ball mounting device 50 starts mounting the ball (Step S50). The closing of the second on-off valve 26, the release of the third on-off valve, and the ball mounting operation by the ball mounting device 50 are controlled by a control unit (not shown) so as to operate in synchronization with each other.

  During the ball mounting operation, whether or not the ball 11 is always filled in the ball tank 12 is detected by the stored ball detection lower limit sensor 20 and the stored ball detection lower limit sensor 21 (step S60). The stored ball detection lower limit sensor 21 sends an alarm to the operator when it detects that the amount of balls stored in the ball tank 12 has fallen below a predetermined amount, and the operator opens the ball lid 22 to replenish the ball tank 12 with the ball 11. To do. When the stored ball detection lower limit sensor 20 detects that the stored amount of the ball 11 is less than or equal to a predetermined limit amount, the ball mounting operation is stopped, and the process returns to step S10 to replenish the ball tank 12, and after step S20 Repeat the operation. When stopping the ball mounting operation, the second opening / closing valve 26 is closed and the third opening / closing valve 28 is released, thereby preventing excess balls from being discharged onto the transfer mask 65.

  If it is determined in step S60 that the ball 11 is full in the ball tank 12 (YES), the ball mounting operation is continued (step S70). Then, the material is removed when the ball mounting on the substrate 51 (or silicon wafer 80) is completed (step S80).

  Even while the ball mounting operation is repeated, the ball 11 is intermittently pumped from the ball supply device 10 to the ball mounting device 50. The ball supply method at that time will be described with reference to FIG.

  FIG. 8 is a process flow explanatory diagram illustrating the main steps of the ball supply method during ball mounting. Since the ball holding portion 88 and the ball supply nozzle 13 are not connected during the ball mounting operation, the pressure feeding of the ball 11 is stopped. 7, when the ball detection lower limit sensor 96 provided in the ball holding portion 88 detects that the ball 11 is not present (step S71), the pressure feeding of the ball 11 is started (step S71). In step S72), the ball 11 is continuously pumped until the ball detection upper limit sensor 97 detects that a predetermined amount of the ball 11 is present (step S73). When the ball detection upper limit sensor 97 detects that a predetermined amount of the ball 11 is present, the pressure feeding of the ball 11 is stopped (step S74). Steps S71 to S74 are repeated while there is a predetermined amount of balls 11 in the ball tank 12 or while the ball mounting operation is continued.

  The ball supply device 10 described above is a device that supplies the ball 11 to the ball mounting device 50. The ball supply device 10 is disposed at a position distant from the ball mounting device 50 in a plan view, and supplies the ball 11 to the ball tank 12 that stores the ball 11 and the ball transfer head units 64A and 64B of the ball mounting device 50. A supply nozzle 13, a ball transfer tube 14 connecting the ball tank 12 and the ball supply nozzle 13, a pressure system for pumping the ball 11 from the ball tank 12 to the ball supply nozzle 13 by compressed gas, and a ball from the ball tank 12 A pressure destruction system that reduces the ball transfer path to the supply nozzle 13 to atmospheric pressure (normal pressure), and a stored ball detection lower limit sensor 20 that detects a lower limit value of the amount of balls stored in the ball tank 12. Based on the ball supply command from the ball transfer head units 64A and 64B. Units 64A, pumping the ball 11 a predetermined amount to 64B.

  With this configuration, the ball mounting apparatus 50 starts ball feeding from the ball supply apparatus 10 to the ball mounting apparatus 50 based on a ball supply command from the ball mounting apparatus 50 (ball transfer head units 64A and 64B). The ball can be supplied to the ball mounting device 50 without stopping 50. Further, if the ball tank 12 is arranged at a position away from the ball mounting device 50 in the plane direction, the ball tank 12 can be easily replenished. When the ball is replenished, the ball 11 is placed on the substrate 51 or the silicon wafer 80. Without falling on the ball mounting device 50, it is possible to prevent mixing of different kinds of balls that have been spilled when the ball mounting device was operated before. Further, in transferring the ball 11, the ball 11 is pumped by the compression system, and the pumping of the ball 11 is stopped at a high speed by the pressure breakage system, so that the ball can be supplied to the ball mounting device 50 without deficiency. . Further, since the mechanical shutter is not used, the ball surface is not damaged.

  In the ball supply device 10 described above, the drive of the pressure system is stopped based on the ball supply stop command from the ball transfer head units 64A and 64B, the drive of the pressure destruction system is started, and the ball is utilized using the vacuum pressure. Return the transfer path to normal pressure at high speed. In this way, the pressure transfer of the ball 11 is stopped, and the ball transfer path from the ball tank 12 to the ball mounting device 50 is reduced to normal pressure, thereby stopping the ball transfer instantaneously. Enables ball supply without excess or deficiency.

  The compressed gas is an inert gas whose pressure is higher than normal pressure and 0.2 MPa or less. The 12 balls 11 in the ball tank 12 can pump the ball 11 at least if the ball tank is made higher than the normal pressure, and if the pressure is 0.2 Mpa or less, which is approximately twice the normal pressure, Sometimes the balls do not collide with each other or collide with the wall of the ball transfer path to damage the ball surface. Further, when an inert gas such as nitrogen gas is used as the compressed gas, an oxide film is formed on the surface of the ball 11 as an electrical bonding material for the electronic component of the ball 11 which is a bonding means between the substrate 51 and the electronic component. Can be prevented from being formed.

  The ball transfer tube 14 has flexibility and flexibility, an inner diameter of 2 mm to 5 mm, and a bending radius of 20 mm or more. Since the ball transfer tube 14 has flexibility and flexibility, it is easy to bend, and the ball tank 11 can be arranged in both the planar direction and the height direction with respect to the ball mounting device 50 (ball transfer head units 64A and 64B). Therefore, the work space is widened and the ball replenishment work to the ball tank 12 is facilitated. Moreover, the ball tank 12 can be enlarged. Further, if the inner diameter of the ball transfer tube 14 is 2 mm to 5 mm and the curvature radius is 20 mm or more, the ball 11 is clogged at the bending position of the ball transfer tube 14 or the balls collide with each other to be damaged. Can be prevented.

  Further, the surface resistance of the contact surface of the ball transfer tube 14 with the ball 11 is set to 1 × 10 −9 Ω or less. The ball transfer tube 14 has flexibility and flexibility. As such a material, for example, it is made of resin, and the resin tube has an insulating property and is charged with static electricity when the balls come into contact with each other, and the balls are adsorbed or the ball transfer tube 14 and the ball 11 are adsorbed. The ball may be delayed. Therefore, the contact resistance can be minimized by forming the conductive film 23 on the inner surface of the ball transfer tube 14 to suppress the generation of static electricity, and the ball 11 can be transferred smoothly.

  The ball mounting device 50 described above is a device for mounting a ball supplied from the ball supply device 10 on a substrate 51 (or a silicon wafer 80 or the like) that is a ball mounted object on which an electrode that is a ball mounted object is formed. is there. The ball mounting device 50 includes ball transfer head units 64A and 64B that transfer a predetermined amount of the ball 11 onto the substrate 51. The ball transfer head units 64A and 64B include a ball holding unit 88 that stores the balls 11 supplied from the ball supply device 10, and a ball discharge that discharges the balls 11 to the substrate 51 (silicon wafer 80) in communication with the ball holding unit 88. A ball detection lower limit sensor 96 that has a passage 94 and detects a lower limit amount of the ball 11 stored in the ball holding unit 88 and transmits a ball supply command to the ball supply device 10, and is stored in the ball holding unit 88. And a ball detection upper limit sensor 97 for detecting an upper limit amount of the ball 11 and transmitting a ball supply stop command to the ball supply device 10.

  The ball detection upper limit sensor 97 detects the amount of balls to be mounted on the substrate 51 (silicon wafer 80), and the ball detection lower limit sensor 96 detects that the required amount of balls to be mounted on the substrate 51 (silicon wafer 80) is insufficient. To do. When the ball mounting device 50 detects that the ball 11 necessary for mounting the ball is supplied to the ball holding portion 88, the ball mounting device 50 stops supplying the ball 11 from the ball supply device 10, and the ball to be mounted on the ball holding portion 88. When it is detected that the amount is insufficient, the ball 11 is supplied to the ball supply device 10. Since the ball mounting apparatus 50 and the ball supply apparatus 10 are interlocked, it is possible to supply the ball to the ball mounting apparatus 50 without stopping the ball mounting apparatus.

  It should be noted that the present invention is not limited to the above-described embodiment, but includes modifications and improvements as long as the object of the present invention can be achieved. For example, in the ball mounting device 50 described above, the ball amount is detected by the ball detection lower limit sensor 96 and the ball detection upper limit sensor 97 provided in the ball holding unit 88, but the ball holding unit 88 is equipped with a load cell or the like. The ball amount can be managed by the weight of the ball 11.

  In the ball supply device 10 of the above-described embodiment, the ball supply amount is managed by the ball holding unit 88 of the ball mounting device 50. However, the ball supply device 10 may be equipped with a ball amount measuring device. Good.

  DESCRIPTION OF SYMBOLS 10 ... Ball supply apparatus, 11 ... Ball, 12 ... Ball tank, 13 ... Ball supply nozzle, 14 ... Tube for ball transfer, 20 ... Storage ball detection minimum sensor, 21 ... Storage ball detection minimum sensor, 50 ... Ball mounting apparatus 51 ... Substrate (ball mounted object), 64A, 64B ... Ball transfer head unit, 80 ... Silicon wafer (ball mounted object), 88 ... Ball holding part, 94 ... Ball discharge passage, 96 ... Ball detection lower limit sensor, 97 ... Ball detection upper limit sensor

Claims (6)

A ball supply device for supplying a ball to a ball mounting device,
A ball tank that is disposed at a position apart from the ball mounting device in a plane and stores the ball;
A ball supply nozzle for supplying the ball to the ball transfer head unit of the ball mounting device;
A ball transfer tube connecting the ball tank and the ball supply nozzle;
A pressurized air system for pumping the ball from the ball tank to the ball supply nozzle by compressed gas;
A pressure breakage system that reduces the ball transfer path from the ball tank to the ball supply nozzle to normal pressure,
A ball supply device for feeding a predetermined amount of the ball to the ball transfer head unit based on a ball supply command from the ball transfer head unit. The ball supply device according to claim 1,
Based on the ball supply stop command from the ball transfer head unit, the drive of the pressure system is stopped, and the drive of the pressure destruction system is started and the ball transfer path is returned to normal pressure at high speed using vacuum pressure. A ball feeder characterized by that. In the ball supply apparatus according to claim 1 or 2,
The ball supply apparatus according to claim 1, wherein the compressed gas is an inert gas having a pressure not lower than normal pressure and not higher than 0.2 MPa. The ball supply device according to claim 1,
The ball supply device according to claim 1, wherein the ball transfer tube has flexibility and flexibility, has an inner diameter of 2 mm to 5 mm, and a bending radius of 20 mm or more. In the ball supply apparatus according to any one of claims 1 to 4,
The ball supply device according to claim 1, wherein a surface resistance of a contact surface of the ball transfer tube with the ball is 1 × 10 ⁻⁹ Ω or less. A ball mounting device for mounting a ball supplied from a ball supply device on a ball mounted object,
A ball transfer head unit that transfers a predetermined amount of the ball to the ball-mounted object;
The ball transfer head unit has a ball holding portion that stores the ball supplied from the ball supply device, and a ball discharge passage that communicates with the ball holding portion and discharges the ball to the mounted object.
A ball detection lower limit sensor for detecting a lower limit amount of the ball stored in the ball holding unit and transmitting a ball supply command to the ball supply device;
And a ball detection upper limit sensor that detects an upper limit amount of the ball stored in the ball holding portion and issues a ball supply stop command to the ball supply device.

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