JPH1174315A - Device and method of bonding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the device and the method of bonding with which the amount of bump deformation can be suppressed to the minimum by increasing the conduction efficiency of the ultrasonic waves from a bonding tool, and to obtain sufficient junction strength by conducting an excellent junction operation. SOLUTION: This bonding device is provided with a bonding tool 90, which is arranged on the rear side 11b of an electronic part 10, presses the pressing surface 91 on the rear side of the electronic part 10 and heats up the electronic part 10 by adding ultrasonic waves, and the second stage substrate supporting part 52 which supports the rear surface 21b of a substrate 20. The external dimensions of the pressing surface 91 of the bonding tool 90 is formed larger than the external dimensions of the electronic part 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bonding apparatus and a bonding method for performing flip-chip bonding for mounting electronic parts such as semiconductors on a substrate using ultrasonic waves and a heating tool. About what you can do.

[0002]

2. Description of the Related Art Flip-chip bonding, in which electrodes of an electronic component and electrodes of a substrate are joined via bumps, has the features of a small mounting area and a short circuit wiring length. Suitable for implementation.

As for the flip chip bonding method, in recent years, examples of development using gold ball bumps whose formation process is relatively easy have been increasing. 7 and 8 are views showing a conventional flip chip bonding method.

In these figures, reference numeral 10 denotes an electronic component;
Indicates a substrate. The electronic component 10 includes a rectangular parallelepiped component main body 11, and one surface thereof has a thickness of 0.7 μm.
The electrode 12 is formed of an aluminum film of m. Substrate 2
0 comprises a substrate body 21 having a thickness of 1.
Electrode 2 is plated with 0 μm gold plating by electrolytic plating.
2 are formed.

First, a bump 13 is formed on an electrode 12 as shown in FIG. That is, the gold wire 3
0 is melted to form a gold ball 31. Then, the pressure is applied to the electrode 12 on the electronic component 10 by the capillary 32, and at the same time, the ultrasonic wave is applied to join. Thereafter, the wire is pulled and the bumps 13 are formed.

The method of bonding the bump 13 and the electrode 22 of the substrate 20 includes a method of interposing an intermediate material such as a conductive paste, a method of directly bonding by thermocompression bonding, and a thermocompression method combined with ultrasonic waves.
The latter has the advantage that the number of steps is small, no intermediate material is required, and the bonding time is short, so that the mounting cost can be reduced.

[0007] Examples of flip chip bonding by thermocompression combined with ultrasonic waves are disclosed in JP-A-8-330880 and “Flip-Chip Assembly Technology”.
equal for SAW Device ”(Pro
c. ISHM'95).

FIG. 8 is a diagram showing an example of a bonding apparatus for performing the above-described flip chip bonding. The bonding apparatus 40 includes a bonding tool 41. Tip 4 of bonding tool 41
2 has a flat shape, and a suction hole 43 is formed in the center thereof. The suction hole 43 is connected to a pressure reducing mechanism (not shown) via a tube (not shown). Further, the bonding tool 41 is instructed by an ultrasonic horn (not shown), and applies a pressing load by driving the ultrasonic horn in the direction of arrow Z in FIG.

In such a bonding apparatus 40, bonding is performed as follows. That is, the back surface of the electronic component 10 is sucked by the bonding tool 41 and the bump 13 is aligned with the electrode 22 of the substrate 20.

On the other hand, the substrate 20 is heated to 200.degree. Next, the bonding tool 41 is driven in the direction of arrow Z in FIG. 8 to apply a pressure of 75 gf to each of the bumps 13. The number of the bumps 13 is 16.

At the same time, the ultrasonic wave is applied to the bonding tool 41.
And is applied to the bonding interface between the bump 13 and the electrode 22. The application of the ultrasonic wave is divided into two stages. That is, in the first stage,
The output is applied at 0.5 W for 800 ms. This is bump 1
The height of the bumps 13 is about 30 μm.

In the second stage, an ultrasonic output of 2 W and 800
ms is applied for bonding. The bonding device 4
When bonding is performed using 0, a bonding strength of about 40 gf per bump is obtained under optimum conditions.

[0013]

The bonding apparatus using the above-described bonding method has the following problems. That is, for an electronic component having a small number of bumps such as four or six, sufficient bonding reliability cannot be obtained with 40 gf per bump. Therefore, it is important to improve the bonding strength per bump.

In order to improve the bonding strength, the transmission efficiency of the ultrasonic wave may be improved. The transmission efficiency depends on the frictional force between the tip 42 of the bonding tool and the back surface of the electronic component 10, and the frictional force depends on the contact area and the bonding load. That is, the transmission efficiency is improved by increasing either the contact area or the bonding load.

However, the external dimensions of the electronic component 10 are very small, for example, 2.1 mm × 1.4 mm, and the contact area is very small because the suction holes 43 are provided. On the other hand, when the pressing pressure is increased to a certain degree or more, the bump 13 is greatly deformed. If an ultrasonic wave is applied in this state, there is a problem that the bonding property between the bump 13 and the electrode 22 is rather lowered and the reliability of the product is lowered. Also,
The force concentrates on the central part of the component body 11 and may be broken.

On the other hand, as shown in FIG. 10, the electronic component 10 is locked by using a bonding tool 46 having a pyramid-shaped concave portion 47 formed at its tip, thereby transmitting ultrasonic waves to the electronic component 10 without loss. Although it has been considered to increase the transmission efficiency, mechanical damage is caused on the edge portion 11a of the electronic component 10, and there is a possibility that the component body 11 may be cracked.

If the time for applying the ultrasonic wave is lengthened, the bonding strength between the bump 13 and the electrode 22 can be ensured, but there is a problem that the manufacturing efficiency is reduced. Further, in the conventional method, there is a problem that good bonding cannot be obtained with respect to a substrate having a thin gold plating thickness and a low bonding property.

According to the present invention, there is provided a bonding apparatus and a bonding apparatus capable of improving the transmission efficiency of ultrasonic waves from a bonding tool, minimizing the amount of bump deformation, and obtaining a sufficient bonding strength by performing good bonding. It is intended to provide a way.

[0019]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems and to achieve the object, an invention according to claim 1 is provided in a bonding apparatus for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate. A bonding tool that presses a back side of the electronic component on which the bump electrodes are not formed through the pressing surface and applies ultrasonic waves to the electronic component; and a substrate support that supports the substrate. And an area where at least the pressing surface of the bonding tool contacts the electronic component is formed to be larger than an area on the back side of the electronic component.

According to a second aspect of the present invention, in the first aspect, at least a pressing surface of the bonding tool is formed to be harder than a material on a back side of the electronic component.

According to a third aspect of the present invention, there is provided a bonding apparatus for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, the bonding device having a pressing surface, and the bump electrode of the electronic component being passed through the pressing surface. A pressing tool is provided on the back side where no electronic component is formed, and a bonding tool that applies ultrasonic waves to the electronic component, and a substrate support portion that supports the substrate, wherein a pressing surface of the bonding tool is subjected to a roughening process. I have.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the back side of the electronic component is subjected to a roughening treatment. According to a fifth aspect of the present invention, in the fourth aspect, the pressing surface of the bonding tool and the back surface of the electronic component are roughened to substantially the same surface roughness.

According to a sixth aspect of the present invention, in a bonding apparatus for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, a mounting tool for positioning the bump electrode of the electronic component on the electrode, and a pressing surface A bonding tool that presses a back surface of the electronic component on which the bump electrodes are not formed through the pressing surface and applies ultrasonic waves to the electronic component, and a substrate supporting unit that supports the substrate And was prepared.

According to a seventh aspect of the present invention, in the sixth aspect of the present invention, the mounting tool has a suction hole through which a back surface of the electronic component is suctioned with a negative pressure. The bonding tool is made of a solid member.

According to an eighth aspect of the present invention, in the invention according to the sixth aspect, the outer diameter of the pressing surface of the mount tool against the electronic component is such that the outer diameter of the pressing surface is in contact with the electronic component. Larger than the outer diameter of the side.

According to a ninth aspect of the present invention, there is provided a bonding apparatus for thermocompression-bonding a bump electrode of an electronic component and an electrode of a substrate, the bonding device having a pressing surface, and the bump electrode of the electronic component through the pressing surface. While pressing the back side where is not formed, a bonding tool that applies ultrasonic waves to the electronic component, a substrate supporting portion that supports the substrate,
A bonding controller is provided for increasing the pressing force of the bonding tool gradually or stepwise and increasing the output of the ultrasonic wave gradually or stepwise.

According to a tenth aspect of the present invention, in a bonding apparatus for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, the bonding device has a pressing surface, and the bump electrode of the electronic component is provided via the pressing surface. A bonding tool that applies ultrasonic waves to the electronic component while pressing the back side on which the electronic component is not formed, an electronic component supporting portion that supports the electronic component, and gradually or stepwise presses the pressing force against the bonding tool. And a bonding control unit for increasing the number of contacts.

According to an eleventh aspect of the present invention, there is provided a bonding apparatus for thermocompression-bonding a bump electrode of an electronic component and an electrode of a substrate, wherein the back surface of the substrate on which the electrodes are not formed is pressed and the substrate is pressed. A bonding tool that applies ultrasonic waves to the electronic component, and an electronic component support that supports the electronic component.

The invention described in claim 12 is the first invention.
In the invention described in 1 above, a tip portion of the bonding tool has a pyramid shape, and a concave portion for locking the substrate is provided.

According to a thirteenth aspect of the present invention, in a bonding method for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, the electronic component is sucked by a mount tool having a suction hole, and the bump of the electronic component is sucked. A positioning step of positioning an electrode on the electrode of the substrate; and a bonding step of applying pressure and heating while applying ultrasonic waves to the electronic component using a solid bonding tool having no suction hole. .

According to a fourteenth aspect of the present invention, in the bonding method for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, a positioning step of positioning the bump electrode of the electronic component on the electrode of the substrate, Pressing the back side of the electronic component on which the bump electrodes are not formed, applying ultrasonic waves to the electronic component, and bonding the component, and the bonding tool gradually increases or decreases the pressing force. While increasing stepwise, the output of the ultrasonic wave is increased gradually or stepwise.

According to a fifteenth aspect of the present invention, in the bonding method for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, a positioning step of positioning the bump electrode of the electronic component on the electrode of the substrate, Pressing the back side of the electronic component on which the bump electrodes are not formed, applying a supersonic wave to the electronic component, and heating, and the pressing force by the bonding tool is gradually or stepwise. Was increased.

According to a sixteenth aspect of the present invention, in the bonding method for bonding a bump electrode of an electronic component and an electrode of a substrate, a supporting step of supporting the back side of the electronic component, and forming the electrode on the substrate And a bonding step of applying an ultrasonic wave to the electronic component via the substrate while pressing the back side that is not performed.

As a result of taking the above-described measures, the following operation occurs. That is, according to the first aspect of the present invention, since the outer dimension of the pressing surface of the bonding tool is formed to be larger than the outer dimension of the electronic component, the contact area is increased and the frictional force is increased. Can be. For this reason, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and good joining can be performed.

According to the second aspect of the present invention, at least the pressing surface of the bonding tool is formed harder than the material on the back side of the electronic component, so that the life of the bonding tool can be extended.

According to the third aspect of the present invention, the frictional force can be increased by roughening. For this reason,
The transmission efficiency of ultrasonic waves can be increased without increasing the crimping load, and good joining can be performed.

According to the fourth aspect of the present invention, since the back side of the electronic component is roughened, the frictional force can be further increased. According to the invention described in claim 5, since the surface roughness of the pressing surface of the bonding tool and the surface roughness of the back surface of the electronic component are substantially the same, the frictional force can be further increased.

According to the invention described in claim 6, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and good joining can be performed. According to the seventh aspect of the present invention, since a hole for suction is not required in the bonding tool, the contact area can be increased, and the frictional force can be increased. For this reason, the transmission efficiency of ultrasonic waves can be increased without increasing the crimping load, and more favorable bonding can be performed.

According to the eighth aspect of the invention, the contact area can be increased, and the frictional force can be increased. For this reason, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and good joining can be performed.

According to the ninth aspect of the present invention, since the pressing force and the ultrasonic output are gradually increased,
Since the bump electrode and the electrode are joined step by step from the point where the contact area is small, the entire contact surface is favorably joined. In addition, bonding can be performed in a short time.

According to the tenth aspect of the present invention, since the pressing force is gradually increased, the bump electrode and the electrode are joined in a stepwise manner from a small contact area. The entire surface is joined well. In addition, bonding can be performed in a short time.

According to the eleventh aspect of the present invention, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and good joining can be performed. Claim 1
According to the invention described in 2 above, since the substrate can be locked to the bonding tool, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and more favorable bonding can be performed. it can.

According to the thirteenth aspect of the present invention, the back surface of the electronic component is suctioned at a negative pressure by using the mount tool, and the positioning step of positioning the bump electrode of the electronic component on the substrate electrode is performed. The back side of the electronic component is pressed by a simple bonding tool, and ultrasonic waves are applied to the electronic component, and a bonding step of heating is provided, so that a hole for suction is not required in the bonding tool. The contact area can be increased, and the frictional force can be increased. For this reason, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and good joining can be performed.

According to the fourteenth aspect, a positioning step of positioning the bump electrode of the electronic component on the electrode of the substrate, pressing the back side of the electronic component, and applying ultrasonic waves to the electronic component, And a bonding step of heating, and the bonding tool is configured to increase the pressing force gradually or stepwise and to increase the output of the ultrasonic wave gradually or stepwise. Since it is joined through stages from the point where the contact area is small,
The entire contact surface is satisfactorily joined. In addition, bonding can be performed in a short time.

According to the fifteenth aspect, a positioning step of positioning the bump electrode of the electronic component on the electrode of the substrate, pressing the back side of the electronic component and applying ultrasonic waves to the electronic component, And, comprising a bonding step of heating, the bonding tool, so as to increase the pressing force gradually or stepwise, because the bonding area through the step from the point where the contact area between the bump electrode and the electrode is small,
The entire contact surface is satisfactorily joined. In addition, bonding can be performed in a short time.

According to the sixteenth aspect of the present invention, a supporting step of supporting the back side of the electronic component and a joining step of pressing the back side of the substrate and applying ultrasonic waves to the substrate are provided. Therefore, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and good joining can be performed.

[0047]

FIG. 1 is a view showing a bonding apparatus 50 according to a first embodiment of the present invention. FIG. 2 shows a main part of the bonding apparatus 50, and FIG. 3 shows an enlarged view of a contact surface between a bonding tool and an electronic component. In these drawings, the same reference numerals are given to the same functional portions as those in FIG.

As the electronic component 10, for example, a six-electrode SAW
An example applied to a device is described below. The external size of the electronic component 10 is 1.7 × 1.4 × 0.4 (mm).
The electronic component 10 is a rectangular parallelepiped lithium tantalate (Li
A component body 11 made of a ceramic material such as TaO ₃ ) is provided, and on one surface thereof, an electrode 12 is formed by an aluminum film having a thickness of 0.7 μm. A bump 13 is bonded to the electrode 12. In the drawing, 11a indicates an edge portion of the component main body 11, and 11b indicates a back surface of the component main body 11.

The substrate 20 has a substrate body 21 made of a ceramic material such as alumina (Al ₂ O ₃ ). One surface of the substrate main body 21 is plated with gold having a thickness of 1.0 μm by electrolytic plating to form an electrode 22. Are formed. In the figure, reference numeral 21a denotes an edge portion of the board main body 21, and 21b denotes a back surface of the component main body 21.

The bonding apparatus 50 has a first stage 51 and a second stage 52 on which the substrate 20 is placed. Reference numeral 60 in FIG. 1 indicates a mount mechanism for positioning the electronic component 10 on the substrate 20 mounted on the first stage 51. In addition, reference numeral 80 in FIG.
A bonding mechanism 80 for mounting the upper substrate 20 and the electronic component 10 positioned thereon is provided.

The mounting mechanism 60 includes the positioning robot 6
1 and a mounting tool 62 provided at the tip of the positioning robot 61. At the tip of the mount tool 62, a suction hole 63 is formed.

The bonding mechanism 80 includes a vertically moving mechanism 81 for driving an ultrasonic horn 82 described later along the direction of arrow Z in FIG. 1, an ultrasonic horn 82 supported by the vertically moving mechanism 81, An ultrasonic source 83 for applying ultrasonic waves to the horn 82 is provided.

At the tip end of the ultrasonic horn 82, a bonding tool 90 made of a solid member having no through hole or the like formed of tungsten carbide is attached. Pressing surface 91 formed at the tip of bonding tool 90
Is formed in a 1.8 × 1.5 (mm) rectangle. That is, the area of the pressing surface 91 is
1 is sufficiently larger than the area of the back surface of the electronic component 10 with which it contacts. The pressing surface 91 is roughened by machining as shown in FIG. 3, and the center line average surface roughness Ra is 2
0 μm. The back surface 11b of the electronic component 10 is also roughened to have the same center line surface roughness Ra as the pressing surface 91 of 20 μm. As a machining method for performing the surface roughening treatment, injection machining such as liquid honing, sand blasting, grit blasting, and shot blasting is suitable.

Further, the vertical movement mechanism 81 and the ultrasonic source 83 are connected to a bonding control section 84 in which a control program described later is stored in advance. In such a bonding apparatus 50, bonding is performed as follows. That is, the back surface 11b of the electronic component 10 is sucked by the mount tool 61, and the bump 13 and the electrode 22 of the substrate 20 mounted on the first stage 51 are aligned using a camera.

Next, the substrate 20 and the electronic component 10 are transferred to the second stage 52. In the second stage 52, the substrate 20 is heated to 200.degree. Next, the bonding tool 9
0 is driven in the direction of arrow Z in FIG. 8, and the bump 13 is pressed with a pressure load as described later. On the other hand, the ultrasonic horn 82 is driven by the ultrasonic source 83 to apply ultrasonic waves to the bonding tool 90. Ultrasonic waves are applied to the bonding interface between the bump 13 and the electrode 22 via the electronic component 10.

The application of the pressure and the application of the ultrasonic wave are controlled by the above-described bonding control unit 84 as shown in FIG. That is, from the state where both the initial crimping load and the ultrasonic output are both zero, each time during 500 ms,
It is controlled to be 00 gf and 2 W. As a result, the bumps 13 are deformed, and the bonding is performed by increasing the ultrasonic output with the increase in the crimping load.

FIG. 5 is a diagram showing a method for evaluating the bonding strength. That is, the substrate 20 is fixed, and the share tool 9 is fixed.
0a is operated in the horizontal direction, so that the bump 13 and the electrode 2
2 is broken, and the breaking strength is used as the bonding strength. As a result of the evaluation, it was found that a sufficient strength of 200 gf / bump was obtained.

On the other hand, the diameter of the bump 13 is about 120 μm, which is much smaller than the conventional 150 μm.
In addition, even when the gold plating thickness of the substrate electrode was as thin as 0.4 μm and the bonding property was low, a shear strength of 140 gf was obtained with a pressure-bonding bump diameter of 120 μm.

As described above, according to the bonding apparatus 50 of the first embodiment, the bonding tool 9
Since the zero pressing surface 91 is larger than the back surface 11b of the electronic component 10 and no suction hole is provided, the contact area is increased and the pressing surface 91 and the back surface 11b of the electronic component 10 are roughened with each other. By increasing the friction force,
Ultrasonic transmission efficiency can be improved. For this reason,
The bonding can be performed efficiently even with a low pressure load, and the amount of deformation of the bump 13 can be minimized. That is, it is possible to prevent the occurrence of cracks in the bumps 13 and to arrange the bumps 13 with high density.

Since the pressure load and the ultrasonic output are gradually increased, the bump 13 and the electrode 22
Since the joining is performed in stages from the point where the contact area is small, the entire contact surface is favorably joined. In addition, bonding can be performed in a short time.

As for the gold plating on the surface of the substrate electrode, a substrate having a thickness of 1.0 μm by electrolytic plating and a substrate having a thickness of 0.4 μm by electroless plating were used. Thus, after bonding, the bump crushing diameter was measured and the joint strength was evaluated by a shear test. As a result, the crushing diameter was 120 μm in diameter, and the bonding strength was 140 (gf / bump).
It became.

On the other hand, FIG. 4B shows an example in which the compression load and the ultrasonic output are increased in five stages. Also in this case, good bonding could be performed similarly to FIG.

Further, FIG. 4C shows that only the pressure
An example in which the number is increased in stages is shown. Even in this case
As in FIG. 4 (a), good bonding can be performed. FIG. 6 is a view showing a bonding apparatus 100 according to the second embodiment of the present invention. In this drawing, the same functional portions as those in FIG. 1 are denoted by the same reference numerals.

As the electronic component 10, for example, a six-electrode SAW
An example applied to a device is described below. The external size of the electronic component 10 is 1.7 × 1.4 × 0.4 (mm).
The electronic component 10 is a rectangular parallelepiped lithium tantalate (Li
A component body 11 made of a ceramic material such as TaO ₃ ) is provided, and on one surface thereof, an electrode 12 is formed by an aluminum film having a thickness of 0.7 μm. Each electrode 12 has a diameter of 90μ.
A gold ball-shaped bump 13 having a height of m and a height of 40 μm is formed.

The substrate 20 is provided with a substrate body 21 made of a ceramic material such as alumina (Al ₂ O ₃ ) or a glass epoxy resin, and one surface thereof is plated with gold having a thickness of 1.0 μm by electrolytic plating. The electrode 22 is formed. The external dimensions of the substrate 20 are 3.0 × 3.0 ×
0.5 (mm).

The bonding apparatus 100 has a bonding tool 101. Bonding tool 101
Is formed with a pyramid-shaped concave portion 103 so that the edge portion 21 a of the substrate 20 can be locked. Further, a suction hole 104 is formed at the center of the distal end portion 102. The suction hole 104 is connected to a pressure reducing mechanism (not shown) via a tube (not shown). In FIG. 6, reference numeral 106 denotes a bonding tool which is driven by a driving source (not shown) through the ultrasonic horn 82 to which the bonding tool is attached, in which a pressing load and ultrasonic waves in the Z direction shown in FIG. Has been granted.

On the other hand, reference numeral 110 in FIG. 6 denotes a component supporting stage, which includes a stage main body 111 and a plate 112 for pressing the side surface of the electronic component 10. In such a bonding apparatus 100, bonding is performed as follows. That is, the bonding tool 101
Sucks the back surface 21b of the substrate 20 with the
Is positioned on the bump 13.

On the other hand, in the component support stage 110,
The electronic component 10 is heated to 200 ° C. Next, the bonding tool 101 is driven in the direction of arrow Z in FIG. 6 to start pressing. At the same time when the crimping load reaches 100 gf,
An ultrasonic wave of about Hz is applied to the bonding interface between the bump 13 and the electrode 22 at an output of 0.5 W and 100 ms. Thereafter, the suction of the substrate 20 by the bonding tool 101 is released, and the bonding tool 101 is pulled up to complete the bonding.

As a result of the joining, the diameter of the bump 13 is about 120
μm, the shear strength was 140 gf, and good joining could be performed. In addition, good bonding was performed in a short time.
It should be noted that mechanical damage due to bonding is not particularly generated on the edge portion 21a of the substrate 20.

As described above, according to the bonding apparatus 100 according to the second embodiment, since ultrasonic waves are transmitted from the bonding tool to the bonding interface with high efficiency, it is possible to obtain good bonding in a short time. it can.

The present invention is not limited to the above embodiment. That is, in the above-described embodiment,
Although tungsten carbide is used as the material for the bonding tool, titanium carbide, diamond,
Other materials such as stainless steel and zirconia may be used. In addition, although application to a SAW device has been described as an electronic component, the invention can be similarly applied to a semiconductor device. The bumps may be plated bumps. Of course, various modifications can be made without departing from the spirit of the present invention.

[0072]

As a result of taking the above-described measures, the following effects are produced. That is, according to the first aspect of the present invention, since the outer dimension of the pressing surface of the bonding tool is formed to be larger than the outer dimension of the electronic component, the contact area is increased and the frictional force is increased. Can be. For this reason, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and good joining can be performed.

According to the second aspect of the present invention, at least the pressing surface of the bonding tool is formed harder than the material on the back side of the electronic component, so that the life of the bonding tool can be extended.

According to the third aspect of the invention, the frictional force can be increased by roughening. For this reason,
The transmission efficiency of ultrasonic waves can be increased without increasing the crimping load, and good joining can be performed.

According to the fourth aspect of the present invention, since the back surface of the electronic component is roughened, the frictional force can be further increased. According to the invention described in claim 5, since the surface roughness of the pressing surface of the bonding tool and the surface roughness of the back surface of the electronic component are substantially the same, the frictional force can be further increased.

According to the invention as set forth in claim 6, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and good joining can be performed. According to the seventh aspect of the present invention, since a hole for suction is not required in the bonding tool, the contact area can be increased, and the frictional force can be increased. For this reason, the transmission efficiency of ultrasonic waves can be increased without increasing the crimping load, and more favorable bonding can be performed.

According to the invention described in claim 8, the contact area can be increased and the frictional force can be increased. For this reason, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and good joining can be performed.

According to the ninth aspect of the present invention, since the pressing force and the ultrasonic output are gradually increased,
Since the bump electrode and the electrode are joined step by step from the point where the contact area is small, the entire contact surface is favorably joined. In addition, bonding can be performed in a short time.

According to the tenth aspect of the present invention, since the pressing force is gradually increased, the bump electrode and the electrode are joined in a step-by-step manner from a small contact area. The entire surface is joined well. In addition, bonding can be performed in a short time.

According to the eleventh aspect, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and good joining can be performed. Claim 1
According to the invention described in 2 above, since the substrate can be locked to the bonding tool, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and more favorable bonding can be performed. it can.

According to the thirteenth aspect of the present invention, the back surface of the electronic component is sucked at a negative pressure by using the mount tool, and the positioning step of positioning the bump electrode of the electronic component on the electrode of the substrate is performed. The back side of the electronic component is pressed by a simple bonding tool, and ultrasonic waves are applied to the electronic component, and a bonding step of heating is provided, so that a hole for suction is not required in the bonding tool. The contact area can be increased, and the frictional force can be increased. For this reason, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and good joining can be performed.

According to the fourteenth aspect of the present invention, a positioning step of positioning the bump electrode of the electronic component on the electrode of the substrate, pressing the back side of the electronic component, and applying ultrasonic waves to the electronic component, And a bonding step of heating, and the bonding tool is configured to increase the pressing force gradually or stepwise and to increase the output of the ultrasonic wave gradually or stepwise. Since it is joined through stages from the point where the contact area is small,
The entire contact surface is satisfactorily joined. In addition, bonding can be performed in a short time.

According to the fifteenth aspect, a positioning step of positioning the bump electrode of the electronic component on the electrode of the substrate, pressing the back side of the electronic component, and applying ultrasonic waves to the electronic component, And, comprising a bonding step of heating, the bonding tool, so as to increase the pressing force gradually or stepwise, because the bonding area through the step from the point where the contact area between the bump electrode and the electrode is small,
The entire contact surface is satisfactorily joined. In addition, bonding can be performed in a short time.

According to the sixteenth aspect of the present invention, there is provided a supporting step of supporting the back side of the electronic component, and a joining step of pressing the back side of the substrate and applying ultrasonic waves to the substrate. Therefore, the transmission efficiency of the ultrasonic wave can be increased without increasing the crimping load, and good joining can be performed.

[Brief description of the drawings]

FIG. 1 is a view showing a bonding apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a main part of the bonding apparatus.

FIG. 3 is a cross-sectional view showing a contact surface between a bonding tool incorporated in the bonding apparatus and an electronic component.

FIG. 4 is a graph showing a relationship between a pressing load and an ultrasonic output in the bonding apparatus.

FIG. 5 is a diagram showing a bonding strength evaluation method.

FIG. 6 is a view showing a bonding apparatus according to a second embodiment of the present invention.

FIG. 7 is a view showing a bump forming method.

FIG. 8 is a diagram showing a conventional bonding method.

FIG. 9 is a graph showing a relationship between a compression load and an ultrasonic output in a conventional bonding method.

FIG. 10 is a diagram showing a bonding tool having a pyramid-shaped concave portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Electronic component 13 ... Bump 20 ... Substrate 22 ... Electrode 50, 100 ... Bonding apparatus 90, 101 ... Bonding tool

Claims (16)

[Claims] 1. A bonding apparatus for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, the bonding device having a pressing surface, and a back surface of the electronic component where the bump electrode is not formed is formed via the pressing surface. A bonding tool for applying ultrasonic waves to the electronic component while pressing, and a substrate supporting portion for supporting the substrate, wherein at least an area of the pressing surface of the bonding tool in contact with the electronic component has an area of the electronic component. A bonding apparatus characterized in that the bonding apparatus is formed to be larger than the area on the back side. 2. The bonding apparatus according to claim 1, wherein at least a pressing surface of the bonding tool is formed harder than a material on a back side of the electronic component. 3. A bonding apparatus for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, wherein the bonding device has a pressing surface, and a back surface of the electronic component where the bump electrode is not formed is formed via the pressing surface. A bonding tool that presses and applies ultrasonic waves to the electronic component; and a substrate support that supports the substrate, wherein a pressing surface of the bonding tool is roughened. . 4. The bonding apparatus according to claim 3, wherein the back side of the electronic component is subjected to a roughening treatment. 5. The bonding apparatus according to claim 4, wherein the pressing surface of the bonding tool and the back surface of the electronic component are roughened to have substantially the same surface roughness. 6. A bonding apparatus for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, comprising: a mounting tool for positioning the bump electrode of the electronic component on the electrode; and a pressing surface, wherein the pressing surface is provided. And a pressing tool for pressing the back surface of the electronic component on which the bump electrode is not formed, and applying a ultrasonic wave to the electronic component; and a substrate supporting portion for supporting the substrate. Bonding equipment. 7. A mounting tool, wherein a suction hole for suctioning the back surface of the electronic component with a negative pressure penetrates, and
The bonding apparatus according to claim 6, wherein the bonding tool is made of a solid member. 8. The electronic device according to claim 6, wherein the outer diameter of the pressing surface of the mounting tool against the electronic component is larger than the outer diameter of the back surface of the electronic component with which the pressing surface contacts. Bonding equipment. 9. A bonding apparatus for thermocompression bonding between a bump electrode of an electronic component and an electrode of a substrate, the bonding device having a pressing surface, and a back surface of the electronic component where the bump electrode is not formed is formed via the pressing surface. While pressing, a bonding tool that applies ultrasonic waves to the electronic component, a substrate supporting portion that supports the substrate, and a pressing force that gradually or stepwise increases the bonding tool with respect to the bonding tool. A bonding controller for increasing the output gradually or stepwise. 10. A bonding apparatus for thermocompression bonding between a bump electrode of an electronic component and an electrode of a substrate, the bonding device having a pressing surface, and the back surface of the electronic component where the bump electrode is not formed is formed via the pressing surface. Pressing, a bonding tool that applies ultrasonic waves to the electronic component, an electronic component supporter that supports the electronic component, and a bonding controller that gradually or stepwise increases the pressing force on the bonding tool. A bonding apparatus comprising: 11. A bonding apparatus for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, wherein the bonding tool presses a back side of the substrate on which the electrodes are not formed and applies ultrasonic waves to the substrate. A bonding device comprising: an electronic component support portion that supports the electronic component. 12. The bonding apparatus according to claim 11, wherein a tip portion of the bonding tool has a pyramid shape and a concave portion for locking the substrate is provided. 13. A bonding method for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, wherein the electronic component is sucked by a mount tool having a suction hole so that the bump electrode of the electronic component is placed on the electrode of the substrate. A bonding method, comprising: a positioning step of positioning; and a bonding step of applying pressure and heating while applying ultrasonic waves to the electronic component using a solid bonding tool having no suction hole. 14. A bonding method for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, wherein: a positioning step of positioning the bump electrode of the electronic component on the electrode of the substrate; Pressing the back side not formed, applying ultrasonic waves to the electronic component, and heating, the bonding tool increases the pressing force gradually or stepwise, and A bonding method characterized by gradually or stepwise increasing the output of ultrasonic waves. 15. A bonding method for thermocompression bonding a bump electrode of an electronic component and an electrode of a substrate, wherein: a positioning step of positioning the bump electrode of the electronic component on an electrode of the substrate; A pressing step of pressing the back side not formed, applying ultrasonic waves to the electronic component, and heating, and gradually increasing a pressing force by the bonding tool in a stepwise manner. Bonding method. 16. A bonding method for bonding a bump electrode of an electronic component and an electrode of a substrate, wherein a supporting step of supporting a rear surface of the electronic component, and pressing a rear surface of the substrate where the electrodes are not formed. A bonding step of applying ultrasonic waves to the electronic component via the substrate.