JP3629850B2 - Crimping method for bumped electronic parts - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for crimping a bumped electronic component.
[0002]
[Prior art]
The electronic component with bumps has a large number of bumps on the lower surface, and all of these bumps are evenly pressure-bonded to the circuit pattern of the substrate, so that they can be correctly mounted on the substrate.
[0003]
However, bumps of electronic components with bumps generally vary in height, and if a soft substrate is used, it is possible to absorb the variation in bumps with the amount of deflection of the substrate. Some substrates, such as substrates, are hard and difficult to bend, and in many cases, variations cannot be sucked by substrate deflection.
[0004]
For this reason, in order to correctly mount the electronic component with bumps as described above, it is necessary to perform pressure bonding while pressing all the bumps against the electrodes of the substrate with equal force. However, in practice, unevenness in crimping is likely to occur due to the bias of some bumps due to variations in bump height, parallelism between the lower surface of the suction tool and the upper surface of the substrate, etc. For this reason, it is known that a crimping head is provided with a tilt mechanism in order to reduce crimping unevenness, and the lower surface of the suction tool (more precisely, the bump arrangement surface) is made to conform to the upper surface of the substrate to absorb the variation in parallelism. Yes.
[0005]
[Problems to be solved by the invention]
However, in the conventional crimping method using the crimping head, when the electronic component with bumps is held by the adsorption tool and the electronic component with bumps is aligned, the adsorption tool is shaken by the tilt mechanism. There was a problem that the relative position of the bumps was distorted. In particular, when a flip chip in which bumps are formed on the electrodes of a semiconductor IC is mounted on a substrate, this problem is particularly noticeable because high-precision mounting is required in addition to a small unevenness of pressure bonding.
[0006]
Accordingly, an object of the present invention is to provide a method for crimping a bumped electronic component that can crimp a bump uniformly and can be aligned with a substrate with high accuracy.
[0007]
[Means for Solving the Problems]
The method for crimping electronic components with bumps according to the present invention includes a suction tool that sucks electronic components with bumps, a support portion that supports the suction tool in a tiltable manner, and a lock mechanism that prohibits tilting of the support portion. a crimping method of the electronic component with bumps according bonding head, adsorption step and the electronic component with bumps adsorbed to the suction tool prohibits tilt to suck the electronic component bumped to the suction tool prohibits tilt The step of recognizing the position of the bumped electronic component and aligning the bumped electronic component with the substrate, the step of detecting the landing with the tilt prohibited, and the bump of the electronic component with the bump adsorbed by the suction tool allowing the tilt A crimping step of crimping the substrate to the substrate.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The method for press-bonding an electronic component with bump according to claim 1 includes an adsorption tool that adsorbs the electronic component with bump, a support portion that supports the adsorption tool in a tiltable manner, and a lock mechanism that prohibits tilting of the support portion. a crimping method of the electronic component with bumps according bonding head, the position of the adsorption step and the electronic component with bumps sucked by the suction tool prohibits tilt to suck the electronic part mounted bumps suction tool prohibits tilt Recognizing the bumps and aligning the bumped electronic component with the substrate , prohibiting the tilt and detecting the landing, and allowing the bump of the bumped electronic component adsorbed by the suction tool to the substrate. A crimping step for crimping. Therefore, in the crimping step, even if the substrate and the bump are not parallel to each other at the beginning, the electronic component with bumps adsorbed by the suction tool is tilted and made to conform to the substrate so that the substrate and the bump are parallel. In other words, the bumps are uniformly crimped and mounting defects can be suppressed.
[0009]
Further, when the position of the electronic component with bumps adsorbed by the adsorption tool is recognized and the electronic component with bumps and the substrate are aligned, tilting is prohibited by the lock mechanism, and high-precision mounting can be performed.
[0010]
Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram of a component mounting apparatus according to an embodiment of the present invention. As shown in FIG. 1, the substrate 1 is held on a substrate holder 2 and positioned by an XY table 3. On the substrate holder 2, a surface plate 4 adjusted to have a sufficient level is installed.
[0011]
Above the substrate holder 2 is provided a Z table 5 for raising and lowering the elevating plate 6 in the Z direction by a Z motor 7, and a head holder 8 is fixed to the front surface of the elevating plate 6. Further, the load cell 9 measures the load acting on the head holder 8 and outputs a load signal to the control unit C. This load signal is used for landing detection described later.
[0012]
The head holder 8 is mounted with a header 11 of the crimping head 10 having a pull stud bolt 12. The crimping head 10 moves up and down integrally with the lifting plate 6. The compressed head 10 is supplied with compressed air discharged from the air supply source 13 through a pipe 14. This compressed air is blown out at the boundary of the arc surface described later. The detailed structure of the pressure bonding head 10 will be described later.
[0013]
On the side of the pressure-bonding head 10, there is provided a recognition device 15 including a camera unit 17 that moves in and out in the direction of the arrow N1 by the moving shaft 16 and observes the upper and lower sides. As shown by a broken line in FIG. 1, the camera unit 17 observes the bumps of the bumped electronic component P and the pattern of the substrate 1 just below the bumped electronic component P attracted to the crimping head 10.
[0014]
Next, the structure of the crimping head 10 will be described with reference to FIGS. A first fixing block 18 having a Y arc surface 19 is fixed to the lower portion of the header 11 by a bolt B1. The first movable block 20 is in close contact with the Y arc surface 19 of the first fixed block 18, and the second movable block 23 having the X arc surface 22 is fixed to the lower portion of the first movable block 20 with a bolt B2. ing. The second movable block 23 is in close contact with the X arc surface 22 of the second fixed block 21.
[0015]
Here, the first movable block 20 is regulated by the X guide plate 24 so as not to be displaced in the X direction with respect to the first fixed block 18, and the second movable block 23 is regulated by the Y guide plate 25. However, it is regulated not to shift in the Y direction. Further, the header 11, the first fixed block 18, the first movable block 20, the second fixed block 21, and the second movable block 23 are formed with a through hole coaxial with the pull stud bolt 12, and in the through hole. The pull-up bar 27 is slidably inserted.
[0016]
In addition, the lower end portion of the through hole is expanded in the second movable block 23 to form a ball seat 26, and a ball 28 provided at the lower end portion of the pull-up bar 27 is positioned on the ball seat 26. ing. The upper end of the pull-up bar 27 is urged upward by a ball 28. Accordingly, the first fixed block 18 and the first movable block 20 that sandwich the Y arc surface 19, and the second fixed block 21 and the second movable block 23 that sandwich the X arc surface 22 are in close contact with each other. The first fixed block 18, the first movable block 20, the second fixed block 21, and the second movable block 23 correspond to a support portion.
[0017]
Here, the compressed air supplied from the pipe 14 can be discharged to the Y arc surface 19 and the X arc surface 22, and when discharged, a slight gap is formed in the Y arc surface 19 and the X arc surface 22. Is done. At this time, the first movable block 20 is allowed to tilt in the direction of arrow M1 relative to the first fixed block 18, and the second movable block 23 is allowed to tilt relative to the second fixed block 21 in the direction of arrow M2. On the contrary, when the ejection is stopped, the above-described two-direction tilt is prohibited by the spring force of the ball 28, and the tilt lock state is established. The pulling rod 27, the ball 28, and the spring 29 correspond to a lock mechanism.
[0018]
The intermediate block 30 is fixed to the lower part of the second movable block 23 by a bolt B3, and the porous plate 31, the heat insulating plate 33, and the heater block 34 are fixed to the lower part of the intermediate block 30 from the top by bolts B4. Has been. A first flow path 32 to which cool air is supplied is formed in the intermediate block 30, and the cool air in the first flow path 32 passes through the inside of the porous plate 31 to the outside from the side surface of the porous plate 31. Discharged. This is because the heater block 34 is heated by the heater 35 so that the heat of the heater block 34 is not transmitted upward from the intermediate block 30, and the first fixed block 18, the first movable block 20, and the second fixed block. The block 21, the second movable block 23, and the like are configured so as not to cause thermal distortion.
[0019]
A suction tool 36 for sucking the bumped electronic component P is fixed to the lower portion of the heater block 34. The bumped electronic component P has a negative flow path 37 formed in the suction tool 36 and the heater block 34. It becomes adsorbed by becoming pressure. Q is a bump of the electronic component P with bump.
[0020]
Next, with reference to FIG. 4, each process of the method for crimping a bumped electronic component of this embodiment will be described.
[0021]
First, in step 1, the discharge of compressed air is stopped and the electronic component P with bumps is attracted to the suction tool 36 in a tilt lock state (step 2).
[0022]
Next, the surface plate 4 is set directly under the pressure bonding head 10, the compressed air is discharged, and the pressure bonding head 10 is lowered toward the surface plate 4 while allowing the tilt, and the bump Q is pressed against the surface plate 4. The bumps Q are slightly crushed (step 4). Thereby, even if there is variation in the height of the bumps Q, the lower bumps of the plurality of bumps Q are aligned on one plane because the higher bumps Q are more crushed.
[0023]
Next, tilt lock is performed (step 5), the posture of the bump Q having a uniform height is restrained as it is, the pressure-bonding head 10 is raised, and the substrate 1 is positioned directly below the pressure-bonding head 10. The table 3 is driven. Then, as shown by the broken line in FIG. 1, the camera unit 17 is brought directly below the bump Q, the pattern of the bump Q and the substrate 1 is observed to recognize the positions of both, and the XY table 3 is driven to Are aligned relative to each other (step 6).
[0024]
When the alignment is completed, the pressure-bonding head 10 is lowered toward the substrate 1 while maintaining the tilt lock (step 7), and the load signal of the load cell 9 is monitored.
[0025]
Here, when the bump Q lands on the substrate 1, the load indicated by the load signal increases rapidly, and it is assumed that the bump Q has landed when this increase is detected (step 8).
[0026]
When landing detection is performed, the tilt lock is released (step 9), and the bumps Q are pressure-bonded to the circuit pattern of the substrate 1 (step 10). Here, even if the upper surface of the substrate 1 and the plane on which the lower end surfaces of the plurality of bumps Q are aligned are not completely parallel, the bumps Q are aligned by performing the tilt in the directions of the arrows M1 and M2. The plane can be made to be the substrate 1 and both can be made completely parallel.
[0027]
As a result, all the bumps Q are uniformly crimped, and mounting defects can be prevented. The load at the time of crimping is adjusted by the control unit c by controlling the Z motor 7 while detecting the load signal of the load cell 9.
[0028]
【The invention's effect】
Since the present invention is configured as described above, bumps can be uniformly crimped without unevenness and mounting defects can be suppressed.
[Brief description of the drawings]
FIG. 1 is a block diagram of a component mounting apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a crimping head according to an embodiment of the present invention. Sectional view [FIG. 4] Flow chart of a method for crimping a bumped electronic component according to an embodiment of the present invention [Explanation of symbols]
10 Crimping head 36 Suction tool P Electronic components with bumps

Claims (2)

A method for crimping electronic components with bumps by a crimping head comprising a suction tool that sucks electronic components with bumps, a support portion that supports the suction tools in a tiltable manner, and a lock mechanism that prohibits tilting of the support portions. Te, an adsorption step for adsorbing an electronic component bumped to the suction tool prohibits tilting said to recognize the position of the electronic component with bumps sucked by the suction tool prohibits tilt and this bumped electronic component A step of performing alignment with the substrate, a step of detecting the landing while prohibiting the tilt, and a step of pressing the bump of the electronic component with the bump adsorbed by the suction tool while allowing the tilt to be bonded to the substrate. A method for crimping a bumped electronic component. Wherein prior to recognition step, by pressing a bump of the adsorbed electronic components bumped into the suction tool allowing the tilt to the base have line leveling the bump, and then raise the pressure bonding head is prohibited tilt The method for crimping electronic components with bumps according to claim 1.

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