JP2003023037A - Bonding tool for electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bonding tool for an electronic component with stable bonding can be made while keeping stable vibration, replacement of a suction part is simple and rapid, and vibration characteristics of the suction part hardly change, even if the suction part is replaced. SOLUTION: A vibrator 17 attached to a side of a horizontally long horn 15 applies longitudinal vibration to the horn 15. The horn 15 has a tapered face 15a which is gradually tapered off toward the center. At the center, a tapered suction part 30 is mounted, freely demountably, with threads 39 or the like. The horn 15 is fixed to a block 13 by four ribs (mounting sections) 15b that are symmetrical when plan-viewed. The ribs (mounting sections) 15b are made as nodes for the standing wave of the vibration while the suction part 30 is made as a loop, and the electronic component can surely be bonded to a face to be bonded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component bonding tool for bonding an electronic component such as a flip chip electronic component with bumps to a surface to be joined such as an electrode of a substrate.

[0002]

2. Description of the Related Art As a method of bonding an electronic component to a surface to be bonded such as an electrode of a substrate, a method using ultrasonic pressure welding is known. In this method, ultrasonic vibration is applied to the electronic component while pressing the electronic component against the surfaces to be joined, and the joint surfaces are caused to vibrate slightly to generate friction, thereby bringing the joint surfaces into close contact with each other. The bonding tool used in this method has a horn that is an elongated rod body that transmits the vibration of the ultrasonic vibrator, which is the vibration source, to the electronic components. A component is sucked, and a load and a vibration are applied to the electronic component, and the electronic component is pressure-bonded to the surfaces to be bonded for bonding.

Conventionally, a horn similar to that used in a wire bonding apparatus has been used as a horn for ultrasonically pressure-welding electronic components. This kind of horn has a cantilever structure, and has a suction portion held at its free end, and an electronic component is suctioned to this suction portion to perform ultrasonic pressure welding.

[0004]

However, since the conventional horn has a cantilever structure, the vibration state is unstable,
It was difficult to perform stable bonding. Further, since the suction part is also held at the free end of the horn, the vibration state was unstable. Further, since the load (load and vibration) at the time of bonding acts on the suction portion, the lower surface (suction surface of the electronic component) is easily worn. When this wear becomes severe, the suction part must be attached to and detached from the horn and replaced.
This exchange needs to be performed easily and quickly, and it is important that the vibration characteristics of the suction part do not change even if the suction part is replaced.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a bonding tool for electronic parts which can perform stable bonding while performing stable vibration. Also, the suction part can be replaced easily and quickly,
Further, it is another object of the present invention to provide a bonding tool for an electronic component in which the vibration characteristics of the suction part do not easily change even if the suction part is replaced.

[0006]

SUMMARY OF THE INVENTION The present invention is an electronic component bonding tool for crimping an electronic component to a surface to be joined while applying load and vibration to the electronic component. A vibrator for giving vibration, a suction part for vacuum-sucking an electronic component in a suction hole, and a mounting part integrally provided with the horn and projecting symmetrically about the suction part in a plan view. The electronic component bonding tool is characterized in that the suction portion is detachably attached to the horn. Further, it is preferable that the suction portion is tapered downward.

In the above structure, the mounting portion serves as a node of the standing wave of the vibration of the horn and the suction portion serves as the antinode, and the vibration can be most effectively used for bonding to the composite surface of the electronic component. If the lower surface of the suction part is worn, the suction part is removed from the horn and replaced. Further, by tapering the suction portion downward, stable bonding can be performed while performing stable vibration on the suction portion, and even if the suction portion is replaced, the vibration characteristics of the suction portion do not change. Will be things.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. 1 is a front view of a bonding apparatus for an electronic component according to an embodiment of the present invention, FIG. 2 is a vertically inverted perspective view of a bonding tool for the electronic component, and FIG. 3A is a front view of a bonding tool for the electronic component. 3 (b) is a bottom view of the bonding tool for the electronic component, and FIG. 3 (c).
Is a front view of a disassembled state of the bonding tool of the electronic component, FIG. 3D is a sectional view of an abutment of the bonding tool of the electronic component, and FIG. 3E is a partial sectional view of the bonding tool of the electronic component. Is.

First, the overall structure of an electronic component bonding apparatus will be described with reference to FIG. Reference numeral 1 denotes a support frame, on the front surface of which a first elevating plate 2 and a second elevating plate 3 are vertically movable. A cylinder 4 is mounted on the first lifting plate 2, and a rod 5 of the cylinder 4 is connected to the second lifting plate 3. A bonding head 10 is attached to the second lift plate 3. A Z-axis motor 6 is provided on the upper surface of the support frame 1. Z-axis motor 6 has vertical feed screw 7
To rotate. The feed screw 7 is screwed into a nut 8 provided on the back surface of the first elevating plate 2. Therefore, when the Z-axis motor 6 is driven and the feed screw 7 rotates, the nut 8 moves up and down along the feed screw 7, and the first lifting plate 2 and the second lifting plate 3 are moved.
Also moves up and down.

In FIG. 1, a substrate 46 as a surface to be joined is shown.
Is placed on the substrate holder 47, and the substrate holder 47
Is placed on the table 48. The table 48 is a movable table, and horizontally moves the substrate 46 in the X direction and the Y direction to position the substrate 46 at a predetermined position.

Reference numeral 42 denotes a camera, which is a uniaxial table 43.
Is attached to. A lens barrel 44 extends forward from the camera 42. The camera 42 is advanced along the uniaxial table 43, and the tip of the lens barrel 44 is adsorbed and held on the lower surface of the bonding tool 14 as shown by the chain line, and an electronic component with bumps such as a flip chip as a bonded object is held. The position of the electronic component 40 and the substrate 46 is observed by the camera 42 in this state. Then, the relative displacement between the electronic component 40 and the substrate 46 is detected based on this observation result. The detected positional deviation is corrected by driving the table 48 to horizontally move the substrate 46 in the X direction and the Y direction, whereby the electronic component 40 and the substrate 46 are aligned.

In FIG. 1, reference numeral 50 denotes a main control unit, which controls the Z-axis motor 6 via a motor drive unit 51, controls the table 48 via a table control unit 52, and a recognition unit 53. Is connected to the camera 42, and the suction device 56 is also connected. The cylinder 4 serving as a pressing unit is connected to the main control unit 50 via the load control unit 54, and the bump output of the rod 5 of the cylinder 4, that is, the bonding tool 14 is used to mount the bumped electronic component 40 on the substrate 46.
The pressing load applied to is controlled. The vibrator 17, which is an ultrasonic vibrator, is connected to the main control unit 50 via the ultrasonic vibrator driving unit 55, and performs ultrasonic vibration according to a command from the main control unit 50.

A holder 12 is joined to the lower end of the main body 11 of the bonding head 10. A block 13 is attached to the holder 12, and a bonding tool 14 is fixed to the block 13. The protrusion 13 a on the side of the block 13 is connected to the suction device 56. The bonding tool 14 will be described below with reference to FIGS. 2 and 3.

As shown in FIGS. 2 and 3, the bonding tool 14 is mainly composed of a horizontally long horn 15. The horn 15 is an elongated rod-shaped body, and has a tapered surface 1 that gradually narrows from both sides toward the center in plan view.
5a. At the center of the horn 15, the suction part 3
0 is projected downward, and ribs 15b are integrally provided with the horn 15 at four positions that are equidistant from the suction portion 30. In order to improve the mounting balance on the block 13, the four ribs 15b are provided so as to project symmetrically in a plan view with the suction portion 30 at the center of the horn 15 as the center. The bonding tool 14 is detachably attached to the lower surface of the block 13 by screwing a screw 18 into the through hole 20 formed in the rib 15b. That is, the rib 15b is a mounting portion for mounting the horn 15 on the block 13.

In FIG. 3 (c), the suction portion 30 has a tapered shape that gradually narrows downward, and both side surfaces thereof are tapered surfaces 31. Further, a suction hole 32 is formed in the center thereof. A protrusion 30 a (FIG. 2) that attracts the electronic component 40 is provided on the lower surface of the suction unit 30. The protrusion 3 is provided on the upper surface of the horn 15 opposite to the suction portion 30.
3 is provided on the lower surface of the horn 15.
A recess 34 into which 3 is fitted is formed. FIG. 3E shows a state in which the protrusion 33 is fitted in the recess 34. In this state, the protrusion 33 is closely fitted into the recess 34, but a slight gap C is secured between the upper surfaces of both sides of the suction portion 30 and the lower surface of the horn 15. Therefore, the contact length between the suction portion 30 and the horn 15 is a length that makes one round around the protrusion 33 indicated by L in the drawing. Thus, by ensuring the clearance C and shortening the contact length L as much as possible, the vibration characteristic of the suction portion 30 is hardly changed even if the suction portion 30 is replaced, and the reproducibility of the vibration characteristic is extremely good. Becomes

In FIG. 3C, a first hole 35 and a second hole 36 having screw threads are formed on the lower surface of the horn 15 on both sides of the recess 34. 37 is a contactor,
As shown in FIG. 3D, the inner end surface 37a has a tapered surface 3
It is a tapered surface that abuts 1. 38 is a contactor 37
The positioning pin is inserted into and fixed to the second hole 36. Insert the screw 39 into the through hole 37c of the abutment member 37,
By inserting the outer end surface 37b of the abutment member 37 into the first hole 35 while abutting the outer end surface 37b of the abutment member 37, the suction portion 30 is detachably attached to the lower surface of the horn 15. In this way, the contact piece 37 is brought into contact with the tapered surface 31 of the suction portion 30 and the lateral displacement of the suction portion 30 is restricted by the pin 38, whereby the suction portion 30 can be firmly attached to the horn 15.

Further, by making both side surfaces of the horn 15 taper surfaces 15a which are gradually narrowed toward the suction portion 30, the vibration of the vibrator 17 can be efficiently and intensively applied to the suction portion 30. Further, by making the suction portion 30 taper downward, the vibration of the suction portion 30 can be stabilized, and the vibration can be intensively and strongly applied to the electronic component 40 sucked on the lower surface thereof. As described above, it is desirable that the suction portion 30 is tapered downward in order to impart vibration to the electronic component 40. The suction portion 30 may have a tapered shape other than the tapered surface 31, for example, a stepwise tapered shape.

In FIG. 1, a suction pad 19 is attached to the protrusion 13a provided on the side surface of the block 13. In FIG. 3C, suction holes 16 a and 16 b communicating with the suction holes 32 of the suction portion 30 are formed in the horn 15, and the suction pad 19 serves as the suction hole 1 on the upper surface of the horn 15.
It is in contact with 6b. Therefore, the suction device 56 (FIG. 1) connected to the suction pad 19 is driven to suck air, so that the suction hole 32 (FIG.
By vacuum suction from (a) and (b), the electronic component 40 with bumps can be vacuum-suctioned and held on the lower surface of the suction portion 30.

In FIG. 2, a vibrator 17 as a vibration imparting means is attached to the side end of the horn 15. By driving the vibrator 17, longitudinal vibration (vibration in the longitudinal direction of the horn 15) is applied to the horn 15, and the suction portion 30 vibrates in the horizontal direction a (the longitudinal direction of the horn 15). Figure 3
As shown in (b), the shape of the horn 15 is such that the width thereof is gradually reduced from both ends in the direction of the center via the tapered surfaces 15a, and thus the horn 15 is transmitted from the vibrator 17 to the suction portion 30. The amplitude of the ultrasonic vibration is amplified in the path, and the vibration having the amplitude equal to or larger than the amplitude oscillated by the vibrator 17 is transmitted to the adsorption unit 30.

Next, a vibration mode excited by the vibrator 17 in the horn 15 will be described. As shown in FIG. 3A, a standing wave A of vibration excited in the horn 15 is generated.
Is the anti-node of the standing wave at the position of the suction surface 30 at the mounting surface of the vibrator 17 and the center of the horn 15, and the positions of the ribs 15b and the suction holes 16b as the fixing portions for fixing the horn 15 to the block 13 are It is shaped like a node of a standing wave. That is, such a standing wave can be generated in the horn 15 by appropriately setting the shape size and mass distribution of each part of the horn 15.

Therefore, the rib 15b, which is a mounting portion, is a standing wave that is equidistantly separated from the adsorption portion 30, which is a position corresponding to the antinode of the standing wave of the vibration of the horn 15, toward both ends of the horn 15. It is provided at a position corresponding to a node. As a result, the bonding tool 14 is fixed to the block 13, and the horn 15 is located at the position of the rib 15b that transmits the pressing force of the cylinder 4 to the horn 15 via the position corresponding to the node of the standing wave.
The displacement due to the vertical vibration is extremely small, and the maximum amplitude is obtained at the position of the suction portion 30 that holds the electronic component 40. Therefore, the ultrasonic vibration can be most effectively used for bonding the electronic component 40.

In FIG. 3A, a protrusion 41 is provided at the center of the upper surface of the horn 15. The protrusion 41 is located on the upper surface of the horn 15 on the side opposite to the suction portion 30.
The mass balance between the suction portion 30 and the mounting means (contact piece 37, pin 38, screw 39, etc.) with respect to the horizontal neutral axis NA of FIG. The operation of this protrusion 41 is as follows. That is, the vibration of the vibrator 17 is transmitted as longitudinal vibration in the longitudinal direction of the horn 15 (arrow a in FIG. 2),
The vertical vibration vibrates the electronic component 40 in the horizontal direction with respect to the joint surface, and the electronic component 40 is bonded by friction with the joint surface.

If there is no protrusion 41, the horn 15 has a mass balance in the Z direction (vertical direction) with respect to the neutral axis NA in the vicinity of the center of the horn 15 due to the suction portion 30 protruding on the lower surface thereof. Crumbling, Z on horn 15
Directional vibration occurs. This vibration in the Z direction acts as a force that strikes the electronic component 40 against the upper surface of the substrate 46, which is the surface to be joined, and thus not only hinders the joining, but also destroys the electronic component 40 in some cases. Then the protrusion 41
To form the suction part 30 with respect to the neutral axis NA.
It is intended to secure the mass balance with and to prevent vibration in the Z direction. That is, the protrusion 41 serves as a mass balance means.

[0024]

According to the present invention, the mounting portion serves as a node of the standing wave of the vibration of the horn and the suction portion serves as the antinode, and the vibration can be most effectively used for bonding to the composite surface of the electronic component. . Further, if the lower surface of the suction portion is worn, the suction portion can be removed from the horn and replaced easily. Further, by tapering the suction portion downward, stable bonding can be performed while performing stable vibration on the suction portion, and even if the suction portion is replaced, the vibration characteristics of the suction portion do not change. Will be things. Further, by providing the mass balancing means, it is possible to prevent the horn from vibrating in the Z direction and reliably bond the electronic component to the surface to be bonded.

[Brief description of drawings]

FIG. 1 is a front view of an electronic component bonding apparatus according to an embodiment of the present invention.

FIG. 2 is an upside down perspective view of a bonding tool for an electronic component according to an embodiment of the present invention.

FIG. 3A is a front view of a bonding tool for an electronic component according to an embodiment of the present invention; FIG. 3B is a bottom view of a bonding tool for an electronic component according to an embodiment of the present invention; (D) A sectional view of a contactor of the bonding tool for an electronic component according to one embodiment of the present invention (e) An electronic component according to one embodiment of the present invention Partial sectional view of the bonding tool of

[Explanation of symbols] 14 Bonding tool 15 horn 15a Tapered surface 17 oscillators 30 Adsorption part 31 Tapered surface 37 Contactor 40 electronic components 41 Projection (mass balance means)

Claims (5)

[Claims] 1. A bonding tool for crimping an electronic component to a surface to be joined while applying a load and a vibration to the electronic component, which has a horizontally long horn, a vibrator for imparting vibration to the horn, and a suction hole. A suction unit that vacuum-sucks electronic components,
An electronic component, comprising: a mounting portion that is symmetrically projected in a plan view around the suction portion and is integrally provided with the horn, and the suction portion is removably mounted on the horn. Bonding tools. 2. The electronic component bonding tool according to claim 1, wherein the suction portion is tapered downward. 3. The suction means, wherein the tapered shape is a tapered shape having a tapered side surface, and an abutting member is brought into contact with the tapered side surface, and the abutting member is detachably fixed to the horn. 3. The electronic component bonding tool according to claim 2, wherein the part is detachably attached to the horn. 4. The bonding tool for an electronic component according to claim 3, wherein the tapered side surface is formed in two surfaces on the left and right in the longitudinal direction of the horn. 5. A mass balance means is provided on the opposite side of the horn from the suction portion.
A bonding tool for electronic components according to any one of 1.