JP2003059972A - Bonding head and bonding apparatus having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To securely join the pad of a semiconductor chip to a lead on a substrate without affecting vibration characteristics when replacing a collet. SOLUTION: A vibration transmission member comprises a first vibration transmission section having a length of (d) at the position of λ/2 in the advancing direction of ultrasonic vibration as a center, a second vibration transmission section that is connected between the first vibration transmission section and a vibrator while having a length of (λ-d)/2 in the advancing direction and has a tapered surface that is gradually widened toward the first vibration transmission section on a side, and a third vibration transmission section that is connected to one end of the first vibration transmission section while having a length of (λ-d)/2 in the advancing direction and has a tapered surface that is gradually widened toward the first vibration transmission section on the side. At the lower section of the first vibration transmission section, a collet retention projection section is provided, where the collet retention projection section comprises a duct section, a positioning groove for positioning a collet provided at the lower end of the duct section, and a collet retention section for retaining the collet by elasticity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bonding head for bonding a surface electrode formed on a pad of a semiconductor chip and a wiring lead formed on a substrate, and a bonding apparatus having the same.

[0002]

2. Description of the Related Art A conventional bonding apparatus for bonding a surface electrode formed on a pad of a semiconductor chip (for example, a flip chip) and a wiring lead formed on a substrate by ultrasonic vibration is shown in FIG. It is known to use a bonding head. As shown in FIG. 16, the conventional bonding head includes an ultrasonic horn 51 connected to a transducer 50 and a collet 52 as a bonding tool attached to the tip of the ultrasonic horn 51.
And a support tool 53 for supporting the ultrasonic horn 51. The bonding head vacuum-sucks the semiconductor chip at the tip of the collet 52 and presses the semiconductor chip onto the wiring lead formed on the substrate to bond the semiconductor chip. At this time, the collet 52 applies ultrasonic vibration to the semiconductor chip. In addition, there is a case where heat or the like is applied as needed to perform the joining.

[0003]

Problems to be Solved by the Invention As shown in FIG.
In a conventional bonding head, a collet 52 as a bonding tool is attached to the tip of an ultrasonic horn 51. Ultrasonic vibration is applied to the collet 52 by the ultrasonic horn 51 at the time of joining the semiconductor chip and the leads of the substrate. At this time, the surface of the collet 52 in contact with the semiconductor chip is abraded by the load and vibration at the time of bonding. If the surface of the collet 52 is worn, normal bonding cannot be performed, so the collet needs to be replaced regularly.

However, when the collet is replaced, the vibration characteristics of the ultrasonic horn may change.
Therefore, it is necessary to confirm the vibration characteristics of the ultrasonic horn and adjust the mounting position of the collet after replacing the collet.

Further, when the collet is integrated with the horn, it is necessary to replace the entire horn, which increases the running cost and requires a long time to replace the horn.

Therefore, according to the present invention, the collet can be freely attached and detached, and the mounting position on the horn when the collet is replaced is always constant, so that the vibration characteristic is not affected and stable. It is an object of the present invention to provide a bonding head capable of performing such bonding and a bonding apparatus including the same.

[0007]

A bonding head according to the present invention is a bonding head for bonding an object to be bonded and a member to be bonded by applying ultrasonic vibration, and a vibrator that generates ultrasonic vibration. One wavelength of the ultrasonic vibration is λ
As a first vibration transmission part having a length of d around the position of λ / 2 in the traveling direction of the ultrasonic vibration, and the first vibration transmission part coupled to the transducer and the traveling direction. A second vibration transmitting portion having a length of (λ-d) / 2 in the side surface, and having a tapered surface on the side surface that gradually widens toward the first vibration transmitting portion, and the first vibration transmitting portion. Vibration transmission having a length (λ-d) / 2 in the traveling direction and gradually widening toward the first vibration transmission portion on the side surface. A vibration transmitting member having a portion, a supporting member provided at a position of an ultrasonic vibration node of the second vibration transmitting portion and the third vibration transmitting portion, and a collet as a bonding tool.
A collet holding protrusion to which the collet is detachably attached is provided under the first vibration transmitting portion.

The collet holding protrusion of the bonding head according to the present invention has a taper on the surface of the vibration transmitting member in the traveling direction of ultrasonic vibration.

The collet holding protrusion of the bonding head according to the present invention includes a duct portion, a positioning groove provided at a lower end of the duct portion for positioning the collet, and a collet holding portion for elastically holding the collet. It consists of

Further, the collet of the bonding head according to the present invention is held by the collet holding protrusion through an adaptor as an auxiliary metal fitting.

Further, the bonding apparatus according to the present invention is
A bonding apparatus having a bonding head for bonding an object to be bonded and a member to be bonded by applying ultrasonic vibration, wherein a vibrator that generates ultrasonic vibration and one wavelength of the ultrasonic vibration are λ Λ in the traveling direction of sound wave vibration
A first vibration transmitting portion having a length of d about the position of / 2, and a length of (λ-d) / 2 in the traveling direction by being coupled between the first vibration transmitting portion and the vibrator. Has a
A second vibration transmission part having a tapered surface on its side surface that gradually widens toward the first vibration transmission part, and another end of the first vibration transmission part connected to the second vibration transmission part (λ−
d) / 2, a vibration transmitting member having a third vibration transmitting portion having a tapered surface on its side surface that gradually widens toward the first vibration transmitting portion, and a second vibration transmitting member. Member and a support member provided at the position of the ultrasonic vibration node of the third vibration transmission unit, a collet as a bonding tool, and the collet detachably attached to the lower portion of the first vibration transmission unit. A bonding head having a collet holding protrusion is provided, and a pressure contact mechanism for driving the bonding head and a control unit for controlling the bonding head and the pressure contact mechanism are provided.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of a bonding head and a bonding apparatus including the same according to the present invention will be described with reference to FIGS.

FIG. 1 is a perspective view showing an embodiment of a bonding head 10 according to the present invention, FIG. 2 (a) is a plan view of the bonding head 10 shown in FIG. 1, and FIG.
2 is a front view of the bonding head 10 shown in FIG.
1C is a diagram showing a vibration mode of the bonding head 10 shown in FIG. 1, FIG. 3A is a plan view showing dimensions of the bonding head 10 shown in FIG. 1, and FIG. 3B is shown in FIG. FIG. 4 is a front view showing the dimensions of the bonding head 10.
Is a cross-sectional view of the collet holding protrusion 4 and the collet 7 in the lower portion of the first vibration transmitting portion 1a, FIG. 5 is a cross-sectional view showing the attachment of the collet 7 to the collet holding protrusion 4, and FIG.
FIG. 7 is a sectional view showing a state in which the collet 7 is attached to the collet holding protrusion 4, FIG. 7 is a sectional view showing fixing of the collet 7 to the collet holding protrusion 4 by the screw 13, and FIG.
9 is a cross-sectional view showing an example in which the collet 7 is held by a force from the holding surface 4ca of the collet holding portion 4c from the left and right and from below, FIG.
FIG. 10 is a cross-sectional view showing an example in which the collet 7 is held by the force from the holding surface 4ca of the collet holding portion 4c and from diagonally below. FIG. 10 shows a collet holding projection of the collet 7 using the adaptor 12. 11 is a cross-sectional view showing an example of attachment to the portion 4, FIG. 11 is a view showing fixing of the vibration transmitting member 1 of the bonding head 10 according to the present invention, and FIG. FIG. 13 is a block diagram showing the configuration of the oscillator 18, and FIG. 13 is a diagram visually showing the displacement state of the vibration transmitting member 1 of the bonding head 10 according to the present invention during vibration. FIG. 14 is the vibration transmitting member shown in FIG. FIG. 15 is an enlarged view of the vicinity of the collet holding protrusion 4 of FIG. 1 to visually represent a displacement state during vibration, and FIG. 15 shows a configuration of a bonding apparatus including the bonding head 10 according to the present invention. It is.

As shown in FIGS. 1, 2 (a) and 2 (b), the bonding head 10 is composed of one vibrator 2 that generates ultrasonic vibrations of a predetermined frequency, and is connected to the vibrator 2. The ultrasonic vibration from the vibrator 2 is applied to the bonding target 22 (see FIG.
The vibration transmitting member 1 that propagates to the
A support member 3 (first support member 3a, second support member
Support member 3b, third support member 3c, and fourth support member 3d), and a collet (adsorber) 7 as a bonding tool for adsorbing the bonding target 22 and applying ultrasonic vibration to the bonding target 22. Have. The fixing member 19 shown by the chain double-dashed line in FIG. 1 is for fixing and supporting the pressure contact mechanism 15 (shown in FIG. 15).

As shown in FIGS. 1 to 3, the vibrator 2 is
For example, it is composed of a PZT (piezoelectric) element or the like, and a voltage of a predetermined frequency is applied from an oscillator 18 via a cable 14 to generate ultrasonic vibration. The total length of the vibrator 2 in the traveling direction u of ultrasonic vibration is set to λ / 2 for one wavelength λ of ultrasonic vibration. The frequency of the voltage applied from the oscillator 18 is 15
Those of kHz to 200 kHz can be used. Therefore, the present embodiment uses a high frequency of 60 kHz out of 15 kHz to 200 kHz.

The vibration transmitting member 1 is made of a metal such as duralumin, stainless steel (SUS), aluminum, titanium alloy, or cemented carbide. The total length of the vibration transmitting member 1 is
The resonance length of the ultrasonic vibration generated by the vibrator 2 in the traveling direction u,
That is, it is set to an integral multiple of a half wavelength (λ / 2) of ultrasonic vibration, and in the present embodiment, the total length in the traveling direction u of ultrasonic vibration generated by the vibrator 2 is twice λ / 2. It is λ.

As shown in FIGS. 2 (b) and 2 (c),
The vibration transmitting member 1 has a λ in the traveling direction u of ultrasonic vibration.
A first vibration transmitting portion 1a having a length of d centering on the position of / 2 (antinode of ultrasonic vibration), and a first vibration transmitting portion 1a.
And the oscillator 2 are coupled to each other and the traveling direction u of ultrasonic vibration is
The second vibration transmitting portion 1b having a length of (λ-d) / 2 and the other end of the first vibration transmitting portion 1a, that is, the end portion on the side facing the vibrator 2 The third vibration transmission unit 1c has a length (λ−d) / 2 in the vibration traveling direction u.

3 (a) and 3 (b) show the dimensions of the first vibration transmitting portion 1a, the second vibration transmitting portion 1b and the third vibration transmitting portion 1c forming the vibration transmitting member 1, respectively. As shown, the first vibration transmitting portion 1a has dimensions of a length d in the traveling direction u of ultrasonic vibration, a width m, and a height h.

Further, as shown in FIGS. 3 (a) and 3 (b), the second vibration transmitting portion 1b and the third vibration transmitting portion 1c.
Of the ultrasonic vibration in the traveling direction u is (λ-d) /
2 and the width of each surface of the second vibration transmitting portion 1b and the third vibration transmitting portion 1c coupled to the first vibration transmitting portion 1a is
The width is m, which is the same as the width of the first vibration transmission unit 1a, and the height is k.
Is. Further, the width of the surface of the second vibration transmitting portion 1b coupled to the vibrator 2 and the end surface of the third vibration transmitting portion 1c (the surface at the position of λ) are n, and the height is the same as the width n. Is. However, the width and height are defined so that n ≧ m and k ≧ n. Further, the width m of the first vibration transmission unit 1a may be set to m = d.

Regarding the shape of the surface of the second vibration transmitting portion 1b, the surface connected to the first vibration transmitting portion 1a is rectangular, the surface connected to the vibrator 2 is square, and the other surface (FIG. 3).
(A), 1bs1, 1bs2, 1b shown in FIG. 3 (b)
t, 1bb) is a trapezoid or a rectangle (when n = m).

As for the shape of the surface of the third vibration transmitting portion 1c, the surface connected to the first vibration transmitting portion 1a has a rectangular shape, the end surface is square, and the other surfaces (FIG. 3 (a), FIG. 3).
1cs1, 1cs2, 1ct, 1cb shown in (b) is a trapezoid or a rectangle (when n = m). It should be noted that the pair of surfaces of the second vibration transmission unit 1b and the third vibration transmission unit 1c (FIGS. 3A and 3B, 1bs1 and 1bs shown in FIG. 3B).
2, 1bt and 1bb, 1cs1 and 1cs2, 1ct and 1
The trapezoids or rectangles of cb) have the same shape.

Further, as shown in FIGS. 2 (b) and 3 (b), the second vibration transmitting portion 1b and the third vibration transmitting portion 1c.
1bs and 1b shown in FIG. 3 (a) and FIG. 3 (b)
s2, 1cs1 and 1cs2) are the first vibration transmission unit 1a.
It has a taper surface that gradually widens toward.

As shown in FIG. 3 (b), the upper surfaces (1bt, 1c) of the second vibration transmitting portion 1b and the third vibration transmitting portion 1c.
t) and the lower surface (1bb, 1cb) have a taper angle (θ) with respect to the central axis in the longitudinal direction of the vibrator 2 and the vibration transmitting member 1. The taper angle (θ) is defined to be within 45 degrees.

As shown in FIGS. 3 (a) and 3 (b), the area of the surface of the second vibration transmitting portion 1b connected to the vibrator 2 is m × k, and the first vibration transmitting portion The area of the surface connected to the portion 1a is n × n. The surface of the second vibration transfer unit 1b that is connected to the vibrator 2 and the surface of the second vibration transfer unit 1b that is connected to the first vibration transfer unit 1a have the same area. That is, the relationship is n × n = m × k. As a result, the vibration transformation ratio of the vibration transmission unit 1 (amplitude amplification ratio of ultrasonic waves) is 1. By changing the width m shown in FIG. 3A, the transformation ratio of ultrasonic vibration can be changed.

As shown in FIGS. 2 (b) and 3 (b),
A semiconductor chip (illustrated in FIG. 15) as a bonding target 22 is pressed against the lower surface of the first vibration transmission unit 1a to vibrate the vibrator 2
A collet 7 is held as a bonding tool for applying ultrasonic vibration from the above to bond the object 22 to be bonded and the substrate (illustrated in FIG. 15) as the member 23 to be bonded. The collet 7 is held by a collet holding protrusion 4 provided below the first vibration transmitting portion 1a.

The collet 7 is shown in FIGS.
As shown in (b), it is attached at a position where the amplitude of ultrasonic vibrations in the first vibration transmission section 1a is maximized.

The attachment / detachment and fixing of the collet 7 to / from the collet holding protrusion 4 will be described below with reference to FIGS. 4 to 10. 4 to 10 are L- of FIG.
It is a sectional view of the collet holding protrusion 4 and the collet 7 as seen from the L direction.

As shown in FIG. 4, the collet holding protrusion 4
Has a tapered surface 4a in the vibration direction U of the vibration transmitting member 1. The collet holding protrusion 4 includes a duct portion 8, a positioning groove 4b provided at a lower end of the duct portion 8, and a tapered surface 4a.
And a collet holding portion 4c having elasticity.

As shown in FIG. 4, the collet 7 has a lower surface to which a suction surface 7a for sucking a semiconductor chip as an object 22 to be bonded and an upper portion to which the collet holding protrusion 4 of the first vibration transmitting portion 1a is inserted and attached. And a held surface 7d for fixing to the collet holding projection 4 of the first vibration transmission portion 1a on the left and right side surfaces, and suction is performed on the central axis perpendicular to the suction surface 7a. A suction hole 7b for carrying out is provided.

The duct portion 8 of the collet holding protrusion 4 is for applying suction force from the suction portion 9 (shown in FIG. 2B). The duct portion 8 is provided on the center line in the longitudinal direction of the first vibration transmission portion 1a, and the first vibration transmission portion 1a.
It can be formed up to the vicinity of the upper surface of a. In addition, the suction unit 9
The first vibration transmitting portion 1a is provided at a substantially central position on the side surface of the longitudinal direction portion or on a symmetry line of the central position, and is connected to the duct portion 8. Although a tube (not shown) can be attached and detached in the present embodiment, the tube may be directly adhered to the duct portion 8, and in that case, the constituent members of the suction portion 9 can be reduced.

Positioning groove 4b of collet holding protrusion 4
As shown in FIG. 4, the positioning protrusion 7c is provided at the lower end of the duct portion 8 and protrudes from the upper surface of the collet 7.
The collet 7 is positioned by inserting.

Collet holding portion 4 of collet holding protrusion 4
c is located in the lower part of the split 4d formed in parallel with the taper surface 4a inside the collet holding projection 4, and has a holding surface 4ca for fixing and holding the collet 7 on its side surface. Further, the collet holding portion 4c has a screw hole 4cb or a screw through hole 4cc.
Is provided, and the collet holding portion 4c is
It has elasticity due to d.

Next, the attachment / detachment of the collet 7 and the fixing / holding of the collet 7 will be described.

As shown in FIG. 5, the screw 13 is inserted into the screw hole 4cb of the collet holding portion 4c, and the collet holding portion 4c.
The holding surface 4ca of c is widened to the left and right (indicated by an arrow in FIG. 5), and the collet 7 is inserted into the positioning groove 4b.

Then, as shown in FIG. 6, the screw 13 is removed so that the collet 7 is fixed and held by the elastic force of the holding surface 4ca of the collet holding portion 4c.

FIG. 6 shows a state in which the object to be joined (semiconductor chip) 22 is adsorbed by the adsorption surface 7a of the collet 7.

In FIG. 7, the collet holding portion 4c is provided with a threaded hole 4cc and a screw hole 4cb penetrating the split 4d in a direction perpendicular to the tapered surface 4a of the collet holding protruding portion 4. Attach the collet 7 to the positioning groove 4b and screw the screw 13 into the screw through hole 4cc of the collet holding portion 4c.
Also, the collet 7 is fixed by inserting the collet 7 into the screw hole 4cb and contracting the holding surface 4ca of the collet holding portion 4c left and right. The screw 13 is used in a state of being attached to the collet holding protrusion 4.

8 and 9 show another example of fixing the collet 7 to the collet holding projection 4.

As shown in FIG. 8, a step is provided on the holding surface 4ca of the collet holding portion 4c, and a step is also provided on the held surface 7d of the collet 7, so that the collet holding projection 4 has a holding surface 4ca. The collet 7 is held by the force from the left and right and from the bottom (the direction of the force is indicated by an arrow in FIG. 8).

FIG. 9 shows the holding surface 4c of the collet holding portion 4c.
The collet holding protrusion 4 holds the collet 7 with a force from the left and right of the holding surface 4ca and a diagonally downward direction (a direction of the force is indicated by an arrow in FIG. 9).

As shown in FIGS. 8 and 9, since the holding force from below acts on the collet 7, the suction hole 7 of the collet 7
The collet holding protrusion 4 can hold the collet 7 in a state where the b and the duct portion 8 of the collet holding protrusion 4 are in close contact with each other.

In the example shown in FIG. 10, the collet 7 is attached to the adaptor 12 as an auxiliary metal fitting, and the collet 7 is attached to the collet holding projection 4 via the adaptor 12. By using the adaptor 12, a small collet 7 for adsorbing and bonding a small chip can be used.

Although the collet holding portions 4c shown in FIGS. 4 to 10 are provided at two positions on the left and right side surfaces of the collet holding protruding portion 4, the collet holding portion 4c can be provided on either side surface of the collet holding protruding portion 4. The collet 7 may be held at one place.

As shown in FIG. 2B, a balance portion 5 having a mass equal to the total mass of the collet holding protrusion 4 and the collet 7 is provided on the upper surface of the first vibration transmitting portion 1a. is doing. The balance part 5 has the same mass as the total mass of the collet holding protrusion 4 and the collet 7, and thereby stabilizes the vibration of the first vibration transmission part 1a.

Further, a suction balance portion 6 having the same mass as the suction portion is provided on one side surface of the longitudinal direction portion of the first vibration transmission portion 1a, and the vibration of the first vibration transmission portion 1a is stabilized. I am trying to make it. A suction mechanism that applies suction force is not shown, but a known suction mechanism is used. Further, although the suction balance section 6 is used in this embodiment, it is not essential and may not be provided.

Next, the bonding head 1 according to the present invention.
As shown in FIGS. 1 to 3, 0 is the first support member 3a, the second support member 3b, the third support member 3c, and the fourth support member 3b as the support member 3 that supports and fixes the vibration transmission member 1. The support member 3d is arranged within the range of the entire length (λ) of the vibration transmission member 1. As shown in FIGS. 2 (a) and 2 (c),
The first support member 3a and the second support member 3b are located at a position of λ / 4 in the progress direction of the ultrasonic vibration from the surface connected to the vibrator 2 on both side surfaces of the second vibration transmission portion 1b (super In addition, the third supporting member 3c and the fourth supporting member 3d are provided on both side surfaces of the third vibration transmitting portion 1c by λ /
It is provided at each of positions 4 (nodes of ultrasonic vibration). The first support member 3a, the second support member 3b, the third support member 3c, and the fourth support member 3d have a columnar shape, and both side surfaces of the second vibration transmission unit 1b and the third support member 3b. The vibration transmitting portion 1c is fitted into and coupled to mounting holes provided on both side surfaces of the vibration transmitting portion 1c.

The collet 7 held by the collet holding protrusion 4 has a first supporting member 3a, a third supporting member 3c, a second supporting member 3b and a second supporting member 3b which are provided at a distance of λ / 2 from each other. Since it is located between the support member 3d of 4 and
Even if the pressing force applied to the bonding target 22 is made uniform and a high load is applied to the vibration transmitting member 1, the vibration transmitting member 1 is prevented from being bent or deformed, and ultrasonic vibration is applied with high efficiency. can do.

The bonding head 10 according to the present invention comprises:
A fixing member 19 for applying a load from the press contact mechanism 15 (shown in FIG. 15) to the collet 7 held by the collet holding protrusion 4 is provided. As shown in FIG. 11, the fixing member 19 includes a first fixing member 19 a and a second fixing member 19 a.
b, the support member 3 is constrained toward the central axis in the longitudinal direction of the vibrator 2 and the vibration transmitting member 1, and the vibration transmitting member 1 is fixed to the fixing member 19. The first fixing member 19a is provided with a circular hole and an elongated hole for coupling with the support member 3. The depth of each hole is dimensioned so as not to contact the vibration transmitting member 1 when the fixing member 19 is joined. The circular hole is the support member 3
The elongated hole is in close contact with the support member 3 in the Z direction and is free in the X direction. Further, the second fixing member 19b is also provided with a circular hole or an elongated hole for coupling with the supporting member 3. At least one place where the support member 3 is fitted to the fixing member 19 is provided. Vibration transmitting member 1 is fixed member 1
In the state of being coupled with 9, the ultrasonic wave is not restrained in the traveling direction of the ultrasonic vibration, so that there is no change in the electrical impedance of the vibration transmitting member 1 and stable vibration is possible.

Further, as shown in FIG. 12, the oscillator 18 for driving the vibrator 2 has an oscillation circuit 18a for oscillating a predetermined frequency, a drive circuit 18b for driving at a frequency oscillated from the oscillation circuit 18a, and a drive circuit. An amplifier circuit 18c for power-amplifying the drive frequency of the circuit 18b, a tank circuit 18d for applying a driving force to the vibrator 2 and matching impedance with the vibrator 2, and an oscillator circuit for receiving the output of the tank circuit 18d. Amplitude feedback circuit 1 for performing amplitude feedback to 18a
8e.

Bonding head 1 having the above structure
FIG. 13 shows a visual representation of the displacement state of the vibration transmission member 1 of 0 at the time of vibration. In addition, FIG. 14 is an enlarged view of the vicinity of the collet holding protrusion 4 of the vibration transmission member 1 to visually represent a displacement state during vibration. The two-dot chain line in FIGS. 13 and 14 represents the position when no vibration occurs.
Further, the vibration transmission member 1 shown by meshes (elements) shows the state of displacement of each part of the vibration transmission member 1 during vibration. As shown in FIGS. 13 and 14, the collet holding protrusion 4 and the collet 7 of the vibration transmitting member 1 during vibration are displaced in the X direction, and no displacement in the Z direction is seen. Also,
As shown in FIG. 13, the first vibration transmitting portion 1a of the vibration transmitting member 1 is not bent in the Z direction. This is because the vertical vibration in the vibration transmission member 1 by the ultrasonic vibrator 2 and the flexural vibration generated in the first vibration transmission portion 1a are combined, and as a result, the vibration only in the X direction is generated. .

The bonding head 10 according to the first embodiment of the present invention has the following effects.

The traveling direction u of the ultrasonic vibration of the vibration transmitting member 1
Is set to λ, and the entire size is reduced. The support member 3 for supporting and fixing the vibration transmitting member 1 and the collet holding protrusion 4 have the entire length (λ) of the vibration transmitting member 1.
And the collet 7 held by the collet holding protrusion 4 is located between the first support member 3a and the second support member 3b that are provided at a distance of λ / 2 from each other. Therefore, the pressing force applied to the bonding target 22 is made uniform. Further, even when a high load is applied to the vibration transmitting member 1, the vibration transmitting member 1 can be prevented from being bent or deformed, and ultrasonic vibration can be applied with high efficiency.
The first support member 3a and the second support member 3b are provided at the nodal points that do not affect the propagation of ultrasonic vibration, and are separated from both ends of the vibration transmission member 1 by an equal distance (λ / 4). Since the vibration transmitting member 1 is not supported in a cantilever manner, the vibration transmitting member 1 is held in a well-balanced manner, and the pressing force on the welding target 22 can be made uniform.

Further, the bonding head 10 is provided with the suction portion 7 for sucking the object 22 to be joined, but the duct portion 8 is provided on the center line in the longitudinal direction of the first vibration transmission portion 1a. In addition, the suction unit 9 is the first vibration transmission unit 1
Since it is desired to provide the suction balance section 6 having a mass equivalent to that of the suction section on one side surface of the longitudinal direction portion of the first vibration transmission section 1a, the suction balance section 6 is provided at a substantially central position of the side surface of the longitudinal direction section of a. The collet holding protrusion 4 can perform stable vibration without losing the balance. Further, the collet 7 held by the collet holding projection 4 generates vibration only in the X direction as shown in FIGS. 13 and 14. That is,
Since the vibration vibrates in parallel with the object 22 to be bonded, the bonding is performed uniformly.

Next, the bonding head 1 according to the present invention
A bonding apparatus including 0 will be described with reference to FIG.

As shown in FIG. 15, the bonding apparatus 2
0 is the mounting table 16 on which the joining target object 22 and the joined member 23 to which the joining target object 22 is joined are placed, and the joining target object 2
The bonding head 10 for bonding the semiconductor chip as the bonding target 22 and the lead of the substrate as the bonding target member 23 by applying ultrasonic vibration to 2, and holding the bonding head 10, and pressing force to the bonding head 10. Load mechanism 15 for applying a load, an oscillator 18, a control unit (CP
U) 17.

Control unit (CPU) 17 as control means
Is configured by a microcomputer or the like and controls the entire apparatus, and operates based on an operation command from an external operation means (not shown).

The mounting table 16 can position the member 23 to be joined, which is conveyed by a conveying means (not shown), at a predetermined position. However, the mounting table 16 may be movable in the two-dimensional directions of the x direction and the y direction (direction perpendicular to the paper surface of FIG. 15) based on the control signal from the control unit 17.

The press-contact mechanism 15 is composed of a drive unit 15a having a motor or the like for moving the bonding head 10 up and down in the direction of arrow z to position the bonding head 10, a motor, an air cylinder, a hydraulic cylinder, and the like. The load mechanism section 15b is configured to apply a pressing force to the bonding target 22 by the bonding head 10 via the fixing member 19 which is variably attached to the tip end portion. The amount of movement of the drive unit 15a and the rod 1 by the load mechanism unit 15b.
The protrusion amount of 5c is controlled by the control unit (CPU) 17.

Next, the operation of the bonding apparatus 20 having the above structure will be described. As shown in FIG.
When the object 22 to be bonded and the member 23 to be bonded are placed and positioned on the mounting table 16, the driving unit 15a operates and the bonding head 10 descends in the arrow z direction and is positioned at a predetermined height. Then, the load mechanism 15b is operated to bring the collet 7 of the bonding head 10 into contact with the object 22 to be bonded and press it with a constant pressure to apply ultrasonic vibration from the vibrator 2 to the object 22 to be bonded. Joining with the member 23 to be joined is performed. Next, the drive unit 15a and the load mechanism unit 15
b is operated to raise the bonding head 10 to a predetermined height to prepare for the next bonding connection. And
By repeating the above operation, the object 22 to be bonded and the member 23
Repeat bonding connection with.

As described above, the bonding head 10 and the bonding apparatus including the same according to the present invention are
Since the collet 7 oscillates in parallel with the IC chip as the object to be joined 22 and there is no flexural vibration or the like,
Stable bonding is possible. In the bonding head 10 according to the present invention, the bonding target 22 is an electronic component such as an IC chip, and the bonding target 23 is a lead formed on the substrate. The bonding target 22 and the bonding target member 23 are described above. As such, bonding connection of a plate member made of metal or synthetic resin is also possible.

[0061]

As described above, according to the bonding head of the present invention, the collet is provided between the first support member and the second support member provided at a distance of λ / 2 from each other. Since it is located, the pressing force applied to the objects to be joined is made uniform. Further, even when a high load is applied to the vibration transmitting member, the vibration transmitting member can be prevented from being bent or deformed, and ultrasonic vibration can be applied with high efficiency.

In the bonding head of the present invention, the collet can be freely attached and detached, and the state of attachment of the collet to the horn is always constant, so that the vibration characteristics are not affected and stable. Bonding becomes possible.

Further, the collet of the bonding head of the present invention vibrates in parallel to the object to be bonded, so that the object to be bonded and the member to be bonded can be reliably bonded, so that the bonding quality is improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a bonding head according to the present invention.

2A is a plan view of the bonding head shown in FIG. 1, FIG. 2B is a front view of the bonding head shown in FIG. 1, and FIG. 2C is a vibration mode of the bonding head shown in FIG. It is a figure.

3A is a plan view showing the dimensions of the bonding head shown in FIG. 1, and FIG. 3B is a front view showing the dimensions of the bonding head shown in FIG.

FIG. 4 is a cross-sectional view of a collet holding protrusion and a collet below the first vibration transmission unit.

FIG. 5 is a cross-sectional view showing how the collet is attached to the collet holding protrusion.

FIG. 6 is a cross-sectional view showing a state in which a collet is attached to a collet holding protrusion.

FIG. 7 is a cross-sectional view showing fixing of the collet to the collet holding protrusion with a screw.

FIG. 8 is a cross-sectional view showing an example in which the collet is held by a force from the holding surface of the collet holding portion and from the left and right and from below.

FIG. 9 is a cross-sectional view showing an example in which the collet is held by the force from the holding surface of the collet holding portion and from the right and left and obliquely below.

FIG. 10 is a cross-sectional view showing an example in which a collet is attached to a collet holding protrusion using an adaptor.

FIG. 11 is a view showing fixing of the vibration transmitting member of the bonding head according to the present invention.

FIG. 12 is a block diagram showing a configuration of an oscillator that drives a vibrator of a bonding head according to the present invention.

FIG. 13 is a diagram visually showing a displacement state of the vibration transmitting member of the bonding head according to the present invention during vibration.

FIG. 14 is a diagram visually enlarging a displacement state during vibration by enlarging the vicinity of a collet holding protrusion of the vibration transmission member shown in FIG.

FIG. 15 is a diagram showing a configuration of a bonding apparatus including a bonding head according to the present invention.

FIG. 16 is a diagram showing a configuration of a conventional bonding head.

[Explanation of symbols]

1 Vibration transmission member 1a First vibration transmission unit 1b Second vibration transmission unit 1bs1, 1bs2 Side surface of second vibration transmission unit 1 bt Upper surface of second vibration transmission unit 1bb Lower surface of second vibration transmission part 1c Third vibration transmission section 1cs1, 1cs2 Side surface of third vibration transmission unit 1ct Third vibration transmitting part upper surface 1cb Lower surface of second vibration transmission unit 2,50 oscillators 3 Support members 3a First support member 3b Second support member 3c Third support member 3d Fourth support member 4 Collet holding protrusion 4a Tapered surface 4b Positioning groove 4c Collet holder 4ca holding surface 4cb screw hole 4cc screw through hole 4d percent 5 Balance section 6 Suction balance section 7,52 Collet (Adsorber) 7a Adsorption surface 7b suction hole 7c Positioning protrusion 7d Hold surface 8 duct 9 Suction section 10 Bonding head 12 compatible 13 screws 14 cables 15 Pressure welding mechanism 15a drive unit 15b Load mechanism section 15c rod 16 table 17 Control unit (CPU) 18 oscillators 19 Fixing member 19a First fixing member 19b Second fixing member 20 Bonding equipment 22 Object to be bonded (semiconductor chip) 23 Member to be joined 51 ultrasonic horn 53 Support

Claims (5)

[Claims] 1. A bonding head for bonding an object to be bonded and a member to be bonded by applying ultrasonic vibration, wherein a vibrator for generating ultrasonic vibration, and one wavelength of the ultrasonic vibration is λ, A first vibration transmission part having a length of d with a position of λ / 2 in the traveling direction of ultrasonic vibration as a center, and a first vibration transmission part coupled between the first vibration transmission part and the vibrator in the traveling direction ( λ-d) / 2, the first
Second vibration transmitting portion having a tapered surface on its side surface that gradually widens toward the vibration transmitting portion, and (λ-d) / 2 in the traveling direction coupled to the other end of the first vibration transmitting portion. And a third vibration transmitting portion having a tapered surface on the side surface that gradually becomes wider toward the first vibration transmitting portion, and the second vibration transmitting portion and the third vibration transmitting portion. A support member provided at a position of the ultrasonic vibration node of the third vibration transmission unit, a collet as a bonding tool, and a collet holding unit to which the collet is detachably attached at a lower portion of the first vibration transmission unit. A bonding head having a protrusion. 2. The bonding head according to claim 1, wherein the collet holding protrusion has a taper on a surface of the vibration transmitting member in a traveling direction of ultrasonic vibration. 3. The collet holding protrusion comprises a duct part, a positioning groove provided at a lower end of the duct part for positioning the collet, and a collet holding part for elastically holding the collet. The bonding head according to claim 1. 4. The bonding head according to claim 1, wherein the collet is held by the collet holding protrusion through an adaptor as an auxiliary metal fitting. 5. A bonding apparatus having a bonding head for bonding an object to be bonded and a member to be bonded by applying ultrasonic vibration, the vibrator generating ultrasonic vibration, and one wavelength of the ultrasonic vibration. Is defined as λ, and a first vibration transmission part having a length of d with a position of λ / 2 in the traveling direction of ultrasonic vibration as a center; and a first vibration transmission part coupled between the first vibration transmission part and the vibrator. The first direction having a length of (λ-d) / 2 in the traveling direction,
Second vibration transmitting portion having a tapered surface on its side surface that gradually widens toward the vibration transmitting portion, and (λ-d) / 2 in the traveling direction coupled to the other end of the first vibration transmitting portion. And a third vibration transmitting portion having a tapered surface on its side surface that gradually becomes wider toward the first vibration transmitting portion, a second vibration transmitting portion, and a third vibration transmitting portion. A support member provided at the position of the ultrasonic vibration node of the vibration transmission part, a collet as a bonding tool, and a collet holding protrusion to which the collet is detachably attached at the lower part of the first vibration transmission part. A bonding apparatus comprising: a bonding head including: a bonding head that drives the bonding head; and a control unit that controls the bonding head and the pressing mechanism.