JP6861017B2 - Ultrasonic bonding method and bonding - Google Patents

Description

The present invention relates to ultrasonic bonding methods and bonded bodies.

An ultrasonic bonding method is known as a method for bonding dissimilar materials.

In the ultrasonic bonding method, ultrasonic vibration is applied to the stacked materials to be bonded, one or both of the materials to be bonded are vibrated, and the frictional force generated between the materials to be bonded causes abrupt heat generation to generate the members to be bonded. This is a bonding method in which the material is locally melted and bonded.

Specifically, the superposed material to be joined is sandwiched between an ultrasonic horn and an anvil from above and below, and while pressurizing, the horn is reciprocated linearly by ultrasonic vibration.

As a result, impurities such as an oxide film are removed by friction between the contact surfaces of the material to be joined, and the new surfaces of the material come into contact with each other to form adhesion nuclei, and the bonding region expands from the adhesion nuclei. Is solid-phase bonded.

By the way, in the ultrasonic bonding method, in order to efficiently transmit the vibration of the ultrasonic horn to the material to be bonded without causing slippage, a plurality of pyramid-shaped protrusions are formed on the pressure surface of the ultrasonic horn. The uneven portion is provided by forming or the like (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2014-213366

However, in the conventional technique, for example, when the bonding material is made of aluminum (Al), Al easily adheres to the ultrasonic horn at the time of bonding, and the groove of the uneven portion of the processed surface of the ultrasonic horn is formed. Al adhered to the ultrasonic horn, and there was a risk that the material to be bonded would stick to the ultrasonic horn after bonding.

When the material to be bonded adheres to the ultrasonic horn in this way, it is necessary to use a chemical or the like to dissolve Al or the like, and there is a problem that the removal work is troublesome.

Further, it is necessary to prepare a spare ultrasonic horn in case the material to be joined adheres to the ultrasonic horn, which has a problem that the cost increases.

The present invention has been made in view of the above circumstances, and an object of the present invention is an ultrasonic bonding method and a bonded body capable of avoiding adhesion between an ultrasonic horn and a material to be bonded and reducing costs. Is to provide.

In order to achieve the above object, the ultrasonic bonding method according to claim 1 is to make the bonding portion of the first material to be bonded and the bonding portion of the second material to be opposed to face each other with the first ultrasonic horn. In the step of sandwiching between the anvil and the first ultrasonic horn, ultrasonic vibration is performed while pressurizing the first ultrasonic horn, and the first ultrasonic horn is bonded to the interface between the first bonded portion and the second bonded portion. A step of forming a nucleus and a step of sandwiching the first material to be bonded and the second material to be bonded between the second ultrasonic horn and the anvil in a state of being temporarily bonded by the adhesion nucleus. Then, the second ultrasonic horn is ultrasonically vibrated while being pressurized to expand the plastic flow region at the interface between the bonding portion of the first material to be bonded and the bonding portion of the second material to be bonded. possess and bonding, the said first ultrasonic horn is provided with a protrusion on the pressure surface, the adhesion nuclei are formed corresponding to the projections, of the second ultrasonic horn The pressure surface in contact with the first material to be bonded or the second material to be bonded is characterized in that the cross-sectional edge portion in the direction orthogonal to the vibration direction has a smooth curved portion .

According to the ultrasonic bonding method according to claim 1, the first ultrasonic horn and the first material to be bonded or the second material to be bonded are pressure-welded only in the step of forming adhesion nuclei at the interface. Therefore, it is possible to effectively prevent the first ultrasonic horn from sticking to the first material to be bonded or the second material to be bonded. Therefore, it is not necessary to remove the material to be joined to the ultrasonic horn as in the conventional case, and it is necessary to prepare a spare ultrasonic horn in case the material to be joined is stuck to the ultrasonic horn. Therefore, the cost can be reduced.

Further, in a state of being temporarily bonded by the adhesion nucleus, the first material to be bonded and the second material to be bonded are sandwiched between the second ultrasonic horn and the anvil, and the second ultrasonic horn is pressurized. Since the plastic flow region is expanded at the interface between the joint portion of the first material to be joined and the joint portion of the second material to be joined by ultrasonic vibration, the joint strength can be improved.

The ultrasonic bonding method according to claim 2, wherein, according to the invention according to claim 1, the first ultrasonic horn is a plurality of pressure surfaces that come into contact with the first material to be bonded or the second material to be bonded. It is characterized in that an uneven portion is formed.

As a result, the vibration of the first ultrasonic horn can be efficiently transmitted to the material to be joined without causing slippage, and adhesion nuclei can be formed at the interface in a short time. It is possible to effectively prevent the ultrasonic horn from sticking to the first material to be joined or the second material to be joined.

In the ultrasonic bonding method according to claim 3, in the invention according to claim 2, the uneven portion is formed between a plurality of pyramidal or conical protrusions formed on the pressure surface and between the protrusions. It is characterized by being composed of a valley.

As a result, the uneven portion can be easily bitten into the surface of the first ultrasonic horn and the first material to be joined or the second material to be joined, and adhesion nuclei are formed at the interface in a shorter time. It is possible to more effectively avoid sticking of the first ultrasonic horn to the first material to be joined or the second material to be joined.

The ultrasonic bonding method according to claim 4 is characterized in that, with respect to the invention according to claim 3, the direction of the tip of the protrusion is inclined in a predetermined direction.

As a result, the uneven portion can be more reliably bitten into the surface of the first ultrasonic horn and the first material to be joined or the second material to be joined, and adhesion nuclei are formed at the interface in a shorter time. , It is possible to more effectively avoid sticking of the first ultrasonic horn to the first material to be joined or the second material to be joined.

The ultrasonic bonding method according to claim 5 is characterized in that, with respect to the invention according to claim 1 , the smooth curved portion is composed of a part of an arc or a part of an ellipse.

As a result, a smooth curved portion can be formed relatively easily, and the cost can be reduced.

The ultrasonic bonding method according to claim 6 comprises the first energy E1 applied to the first ultrasonic horn and the second energy E1 according to the invention according to any one of claims 1 to 5. The relationship with the second energy E2 applied to the ultrasonic horn is characterized in that E1 <E2.

As a result, a relatively weak energy E1 is applied to the first ultrasonic horn to more effectively prevent the first ultrasonic horn from sticking to the first material to be joined or the second material to be joined. A large amount of energy E2 is applied to the second ultrasonic horn to more reliably expand the plastic flow region at the interface between the joint portion of the first joint material and the joint portion of the second joint material, thereby increasing the joint strength. It can be further improved.

Assembly according to claim 7 is the joined body joined by ultrasonic bonding method according to claim 1 to any one of claims 6, wherein the first material to be joined or the second object On the surface of the bonding material, the portion where the first ultrasonic horn and the second ultrasonic horn are pressure-welded is above at least a part of the dot-shaped first indentation by the first ultrasonic horn. In addition, the linear second indentation by the second ultrasonic horn is formed in an overlapping manner.

As a result, by visually confirming whether or not the linear second indentation is formed on at least a part of the dot-shaped first indentation, the materials to be joined adhere to each other. It is possible to easily determine whether the state is temporarily joined by the nucleus or the state is mainly joined by expanding the plastic flow region at the interface.

According to the present invention, it is possible to provide an ultrasonic bonding method and a bonded body that can avoid sticking between the ultrasonic horn and the material to be bonded and reduce the cost.

It is a process diagram which shows the flow of the ultrasonic bonding process in the ultrasonic bonding method which concerns on this invention. It is a schematic explanatory drawing which shows the application order of the ultrasonic bonding machine which applies the ultrasonic bonding method which concerns on this invention. It is a schematic block diagram which shows the schematic structure of the 1st ultrasonic bonding machine applied to the pre-stage process of the ultrasonic bonding method which concerns on this invention. It is sectional drawing (a)-(d) which shows the structural example of the 1st ultrasonic horn provided in the 1st ultrasonic bonding machine applied to the pre-stage process. It is a plan view (a), (b) which shows the structural example of the 1st ultrasonic horn provided in the 1st ultrasonic bonding machine applied to the pre-process. It is a side sectional view (a) and AA line sectional view (b) which show the structural example of the adhesion nucleus formed at the interface of the 1st joint material and the 2nd joint material in the pre-stage process. It is a schematic block diagram which shows the schematic structure of the 2nd ultrasonic bonding machine applied to the post-process of the ultrasonic bonding method which concerns on this invention. It is a perspective view (a), (b) which shows the structural example of the 2nd ultrasonic horn provided in the 2nd ultrasonic bonding machine applied to the post-step process. It is a side sectional view (a) and BB line sectional view (b) which show the structural example of the plastic flow region formed at the interface of a 1st joint material and a 2nd joint material in a post-step process. Imaging views (a) and (b) relating to the appearance of a comparative example of a bonded body to which a general ultrasonic bonding method is applied, and imaging views (c) relating to the appearance of a bonded body to which the ultrasonic bonding method according to the present invention is applied. ).

Hereinafter, the ultrasonic bonding method according to the present invention will be described with reference to FIGS. 1 to 10.

(Outline of ultrasonic bonding process)
FIG. 1 is a process diagram showing the flow of an ultrasonic bonding process in the ultrasonic bonding method according to the present invention, and FIG. 2 shows the order of application of ultrasonic bonding machines 1A and 1B to which the ultrasonic bonding method according to the present invention is applied. It is a schematic explanatory drawing which shows.

As shown in the process diagram of FIG. 1, the ultrasonic joining process includes a pre-stage process (single-strike process) consisting of the first process S1 and the second process S2, and a third process S3 and a fourth process S4. It is composed of a post-stage process (double striking process).

First, as shown in FIGS. 1 and 2, in the first step S1 of the ultrasonic bonding method, a bonding portion of the first material to be bonded M1 made of aluminum or the like and a second coating made of aluminum or the like are also used. The bonding material M2 is opposed to the bonding portion, and is sandwiched and fixed between the first ultrasonic horn H1 and the anvil A1 provided in the first ultrasonic bonding machine 1A. A configuration example of the first ultrasonic bonding machine 1A and the like will be described later.

Next, in the second step S2 of the ultrasonic bonding method, the first ultrasonic horn H1 is ultrasonically vibrated in the D1 direction while being pressurized by the pressure F1 to be bonded to the bonding portion of the first material to be bonded M1. Adhesive nuclei C are formed at the interface 150 of the material M2 with the bonding portion (see FIG. 6). As a result, the first material to be joined M1 and the second material to be joined M2 are temporarily joined by the adhesion nucleus C.

Next, as shown in FIGS. 1 and 2, in the third step S3 of the ultrasonic bonding method, the first bonded material M1 and the second bonded material M2 are temporarily bonded by the adhesion nucleus C. Is sandwiched and fixed between the second ultrasonic horn H2 provided in the second ultrasonic joining machine 1B and the anvil A1. A configuration example of the second ultrasonic bonding machine 1B and the like will be described later.

Next, in the fourth step S4 of the ultrasonic bonding method, the second ultrasonic horn H2 is ultrasonically vibrated in the D1 direction while being pressurized by the pressure F2 to be bonded to the bonding portion of the first material to be bonded M1. The plastic flow region 50 (see FIG. 9) is enlarged and main-bonded at the interface 150 of the material M2 with the bonding portion to obtain a bonded body 500 (see FIG. 10 (c)).

Details of the adhesion nucleus C, the plastic flow region 50, and the like will be described later.

Further, the relationship between the first energy E1 applied to the first ultrasonic horn H1 and the second energy E2 applied to the second ultrasonic horn H2 is E1 <E2.

For example, the first energy E1 may be about 50 J and the second energy E2 may be about 1200 J. That is, the second energy E2 may be about 20 to 30 times the first energy E1.

Further, in the example shown in FIG. 2, the first material to be joined M1 is on the upper side and the second material to be joined M2 is on the lower side, but the present invention is not limited to this, and even if the vertical positions of the two are reversed. Good.

(About the first ultrasonic bonding machine)
A schematic configuration of a first ultrasonic bonding machine applied to the pre-stage step of the ultrasonic bonding method according to the present invention will be described with reference to FIGS. 3 to 6.

Here, FIG. 3 is a schematic configuration diagram showing a schematic configuration of a first ultrasonic bonding machine 1A applied to a pre-stage step of the ultrasonic bonding method according to the present invention.

The first ultrasonic bonding machine 1A shown in FIG. 3 is roughly composed of a power supply 3, an oscillator 2, and an ultrasonic bonding machine main body 15.

The power supply 3 is an AC power supply that drives an oscillator 2 or the like that vibrates the first ultrasonic horn H1 included in the ultrasonic bonding machine main body 15.

The ultrasonic bonding machine main body 15 includes a first ultrasonic horn H1 and an anvil A1.

Then, with the joint portion of the first material to be joined M1 and the joint portion of the second material to be joined M2 facing each other, the first ultrasonic horn H1 and the anvil A1 sandwich the joint portion, and the first ultrasonic horn H1 The ultrasonic vibration in the D1 direction generated by the vibrator 2 is propagated while pressurizing with the pressure F1 to stick to the interface 150 between the joint portion of the first joint material M1 and the joint portion of the second joint material M2. Nucleation C is formed (see FIG. 6).

As a result, the first material to be joined M1 and the second material to be joined M2 are temporarily joined by the adhesion nucleus C.

(About the first ultrasonic horn)
Next, a configuration example of the first ultrasonic horn H1 will be described with reference to FIGS. 4 and 5.

4 (a) to 4 (d) are cross-sectional views showing a configuration example of the first ultrasonic horns H1a to H1d included in the first ultrasonic bonding machine 1A, and FIGS. 5 (a) and 5 (b) are the first. It is a top view which shows the structural example of the 1st ultrasonic horns H1a and H1b provided in 1 ultrasonic bonding machine 1A.

The first ultrasonic horn H1a according to the first configuration example shown in FIGS. 4 (a) and 5 (a) has a plurality of pressure surfaces 60 in contact with the first material to be joined M1 or the second material to be joined M2. An uneven portion is formed.

More specifically, the uneven portion is formed between a plurality of pyramidal or conical protrusions 10a and protrusions 10a formed on the pressure surface 60 (16 in the example shown in FIG. 5A). It is composed of a valley portion 30a. The tip of the protrusion 10a has a sharp shape.

The first ultrasonic horn H1a is made of an aluminum alloy, a titanium alloy, or the like, depending on the materials of the first material to be joined M1 and the second material to be joined M2.

Further, the direction (θ1) of the tip of the protrusion 10a of the first ultrasonic horn H1a is substantially perpendicular to the horizontal pressure surface 60.

With such a configuration, the first ultrasonic horn H1a according to the first configuration example surely bites into the surface of the first material to be joined M1 to be pressure-welded, and the ultrasonic vibration of the first ultrasonic horn H1a is generated. 1 Adhesive nuclei C can be formed at the interface 150 in a short time by efficiently transmitting to the material M1 to be bonded without causing slippage. Therefore, sticking of the first ultrasonic horn H1a and the first material to be joined M1 can be effectively avoided.

In the first ultrasonic horn H1b according to the second configuration example shown in FIGS. 4 (b) and 5 (b), a plurality of uneven portions are formed on the pressure surface 60 (in the example shown in FIG. 5 (b)). It is composed of 16) pyramidal or conical protrusions 10b and valleys 30b formed between the protrusions 10b. The tip of the protrusion 10b has a chamfered shape.

The first ultrasonic horn H1b is made of an aluminum alloy, a titanium alloy, or the like, depending on the materials of the first material to be joined M1 and the second material to be joined M2.

Further, the direction (θ1) of the tip of the protrusion 10b of the first ultrasonic horn H1b is substantially perpendicular to the horizontal pressure surface 60.

With such a configuration, the first ultrasonic horn H1b according to the second configuration example bites into the surface of the first material to be joined M1 to be pressure-welded, and the first ultrasonic vibration of the first ultrasonic horn H1b is applied. Adhesive nuclei C can be formed at the interface 150 in a short time by efficiently transmitting to the bonding material M1 without causing slippage. Therefore, sticking of the first ultrasonic horn H1b and the first material to be joined M1 can be effectively avoided.

In the first ultrasonic horn H1c according to the third configuration example shown in FIG. 4C, the uneven portion is formed between the plurality of pyramidal or conical protrusions 10c and the protrusions 10c formed on the pressure surface 60. It is composed of a valley portion 30c to be formed. The tip of the protrusion 10c has a sharp shape, and the direction (θ2) of the tip of each protrusion 10c has an angle of, for example, about 60 ° in the lower right direction with respect to the horizontal pressure surface 60. doing.

The first ultrasonic horn H1c is made of an aluminum alloy, a titanium alloy, or the like, depending on the materials of the first material to be joined M1 and the second material to be joined M2.

With such a configuration, the first ultrasonic horn H1c according to the first configuration example surely bites into the surface of the first material to be joined M1 to be pressure-welded, and the ultrasonic vibration of the first ultrasonic horn H1c is generated. 1 Adhesive nuclei C can be formed at the interface 150 in a short time by efficiently transmitting to the material M1 to be bonded without causing slippage. Therefore, sticking of the first ultrasonic horn H1c and the first material to be joined M1 can be effectively avoided.

In the first ultrasonic horn H1d according to the fourth configuration example shown in FIG. 4 (d), the uneven portions are a plurality of pyramidal or conical protrusions 10d and 10e and protrusions 10d formed on the pressure surface 60. It is composed of valleys 30d and 30e formed between 10e and the like.

The tips of the protrusions 10d and 10e have a sharp shape, and the direction (θ3) of the tips of the protrusions 10d is an angle of, for example, about 60 ° in the lower right direction with respect to the horizontal pressure surface 60. The direction (θ4) of the tip of the protrusion 10e has an angle of, for example, about 60 ° in the lower left direction with respect to the horizontal pressure surface 60.

The first ultrasonic horn H1d is made of an aluminum alloy, a titanium alloy, or the like, depending on the materials of the first material to be joined M1 and the second material to be joined M2.

With such a configuration, the first ultrasonic horn H1d according to the fourth configuration example surely bites into the surface of the first material to be joined M1 to be pressure-welded, and the ultrasonic vibration of the first ultrasonic horn H1d is generated. 1 Adhesive nuclei C can be formed at the interface 150 in a short time by efficiently transmitting to the material M1 to be bonded without causing slippage. Therefore, sticking of the first ultrasonic horn H1d and the first material to be joined M1 can be effectively avoided.

Further, according to the first ultrasonic horns H1a to H1d according to the first to fourth configuration examples, the work of removing the material to be joined attached to the ultrasonic horn as in the conventional case becomes unnecessary, and the ultrasonic horn H1a It is not necessary to prepare a spare ultrasonic horn in case the material to be joined adheres to H1d, and the cost can be reduced.

Here, a configuration example of the adhesion nucleus C formed by the first ultrasonic horns H1 (H1a to H1d) will be described with reference to FIG.

FIG. 6A is a side sectional view showing a configuration example of the adhesion core C formed at the interface 150 between the first material to be joined M1 and the second material to be joined M2 in the previous step, and FIG. 6B is a side sectional view. , A cross-sectional view taken along the line AA.

As shown in FIG. 6 (b), the adhesion core C formed at the interface 150 between the first material to be joined M1 and the second material to be joined M2 is shown in, for example, FIG. 5 (a) or FIG. 5 (b). A total of 16 pieces are formed in the vertical and horizontal directions corresponding to the positions of the 16 pyramidal or conical protrusions 10a and 10b formed on the pressure surface 60 of the ultrasonic horns H1a and H1b.

Needless to say, the number of adherent nuclei C formed at the interface 150 can be increased or decreased depending on the number of protrusions 10a and the like of the first ultrasonic horn H1.

Further, the size (capacity), depth (height), etc. of the adherent nucleus C can be controlled by increasing or decreasing the amount of the first energy E1 applied to the first ultrasonic horn H1.

(About the second ultrasonic bonding machine)
The schematic configuration of the second ultrasonic bonding machine 1B applied to the subsequent step of the ultrasonic bonding method according to the present invention will be briefly described with reference to FIG. 7.

Since the overall configuration of the second ultrasonic bonding machine 1B is the same as that of the first ultrasonic bonding machine 1A, the same reference numerals are given and duplicate description will be omitted.

The difference between the second ultrasonic bonding machine 1B and the first ultrasonic bonding machine 1A is that the ultrasonic bonding machine main body 15 is provided with a second ultrasonic horn H2 instead of the first ultrasonic horn H1. At the point.

Then, in a state of being temporarily bonded by the adhesion nucleus C, the first material to be bonded M1 and the second material to be bonded M2 are sandwiched between the second ultrasonic horn H2 and the anvil A1, and the second ultrasonic wave is generated. While pressurizing the horn H2 with the pressure F2, the ultrasonic vibration in the D1 direction generated by the vibrator 2 is propagated, and the interface 150 between the joint portion of the first joint material M1 and the joint portion of the second joint material M2. In, the first material to be bonded M1 and the material (Al or the like) constituting the second material to be bonded M2 are stirred by ultrasonic vibration to expand the plastic flow region (see FIG. 9), and this bonding is performed.

As a result, a bonded body 500 (see FIG. 10 (c)) to which the ultrasonic bonding method according to the present invention is applied can be obtained.

(About the second ultrasonic horn)
Next, a configuration example of the second ultrasonic horn H2 will be described with reference to FIG.

8 (a) and 8 (b) are perspective views showing a configuration example of a second ultrasonic horn H2 included in the second ultrasonic bonding machine 1B applied to the subsequent process.

The pressure surface 70 in contact with the first material to be joined M1 of the second ultrasonic horn H2 is configured so that the cross-sectional edge portion in the direction orthogonal to the vibration direction D1 has a smooth curved portion 20.

More specifically, the smooth curved portion 20 is composed of a part of an arc (for example, 200R or the like) or a part of an ellipse.

Here, the first configuration example shown in FIG. 8A has one smooth curved portion 20 extending in the longitudinal direction of the lower surface of the second ultrasonic horn H2a.

Further, the second configuration example shown in FIG. 8B has two smooth curved portions 20a and 20b extending in the longitudinal direction of the lower surface of the second ultrasonic horn H2b.

The configuration is not limited to the configuration examples shown in FIGS. 8A and 8B, and three or more smooth curved portions extending in the longitudinal direction are formed on the lower surface of the second ultrasonic horn H2. May be good.

9 (a) is a side sectional view showing a configuration example of a plastic flow region 50 formed at the interface 150 between the first material to be joined M1 and the second material to be joined M2 in the subsequent step, and FIG. 9 (b) is a side sectional view. , Is a sectional view taken along line BB.

As shown in FIG. 9B, a relatively wide plastic flow region 50a is formed at substantially the center of the interface 150 between the first material to be joined M1 and the second material to be joined M2.

Alternatively, although not shown, it is presumed that a gradation-like plastic flow region 50 that gradually becomes thinner from the center of the interface 150 toward the edge may be formed.

In this way, from the state of being temporarily joined by the adhesion nucleus C, the second ultrasonic horn H2 is pressurized and ultrasonically vibrated to cause the joining portion of the first material to be joined M1 and the second material to be joined M2. At the interface 150 with the joint portion, the material (Al or the like) constituting the first material to be bonded M1 and the second material to be bonded M2 is stirred by ultrasonic vibration to expand the plastic flow region 50, so that the plastic flow region 50 is expanded. The strength can be improved.

Further, since the pressure surface 70 of the second ultrasonic horn H1 has a curved portion 20 whose cross-sectional edge in the direction orthogonal to the vibration direction D1 is smooth, the plastic flow region 50 is expanded at the interface 150 and finally joined. In the process, it is possible to avoid a situation in which the second ultrasonic horn H1 and the first material to be joined M1 stick to each other.

Further, since the smooth curved portion 20 can be formed of a part of an arc or a part of an ellipse, it can be formed relatively easily and the cost can be reduced.

(About the appearance characteristics of the bonded body to which the ultrasonic bonding method is applied)
With reference to FIG. 10, the external features of the bonded body according to the comparative example and the external features of the bonded body to which the ultrasonic bonding method according to the present invention is applied will be described.

10 (a) and 10 (b) are imaging views relating to the appearance of a comparative example of a bonded body to which a general ultrasonic bonding method is applied, and FIG. 10 (c) is an ultrasonic bonding method according to the present invention. It is an image (c) which concerns on the appearance of the bonded body.

In the comparative example shown in FIG. 10A, for example, an ultrasonic horn having a plurality of pyramidal or conical protrusions as shown in FIG. 4A is used to bond the first material M1 and the second material to be bonded. The appearance of the first material to be bonded M1 side when ultrasonic bonding of the material M2 is performed once is shown.

As can be seen from FIG. 10A, dot-shaped indentations 200 of an ultrasonic horn having a plurality of pyramidal or conical protrusions are left on the surface of the first material to be joined M1.

Further, in the comparative example shown in FIG. 10B, for example, an ultrasonic horn having one smooth curved portion extending in the longitudinal direction of the lower surface as shown in FIG. 8A is used with the first material to be bonded M1. The appearance of the first material to be bonded M1 side when the second material to be bonded M2 is ultrasonically bonded once is shown.

As can be seen from FIG. 10B, linear indentations 300 extending in the longitudinal direction of the first material to be joined M1 are left on the surface of the first material to be joined M1.

On the other hand, FIG. 10C shows the appearance of the bonded body 500 to which the ultrasonic bonding method according to the present invention is applied.

As can be seen from FIG. 10 (c), in the bonded body 500 bonded by the ultrasonic bonding method according to the present invention, the first ultrasonic horn H1 and the second ultrasonic horn H1 and the second ultrasonic horn H1 and the second ultrasonic horn H1 are formed on the surface of the first material to be bonded. At the site where the ultrasonic horn H2 is pressure-welded, a linear second indentation by the second ultrasonic horn H2 is placed on at least a part of the dot-shaped first indentation 200 by the first ultrasonic horn H1. Indentations 300 are formed on top of each other.

As a result, by visually confirming whether or not the linear second indentation 300 is formed on at least a part of the dot-shaped first indentation 200, the materials to be joined M1 and M2 Whether they are temporarily joined by the cohesive nucleus C that has been subjected to only the first step (that is, the state shown in FIG. 10A), the second step is carried out to expand the plastic flow region at the interface. It is possible to easily determine whether the state is in the main bonded state.

Further, it is possible to distinguish from the state in which only the post-stage process is performed (that is, the state shown in FIG. 10B) without going through the pre-stage process, and the two steps of the pre-stage process → the post-stage process are not performed. Bonding defects can be easily determined.

(Other)
In performing the ultrasonic bonding method according to the present invention, when the ultrasonic bonding by the first ultrasonic horn H1 and the ultrasonic bonding by the second ultrasonic horn H2 are performed, the first material to be bonded M1 and the second material to be bonded are executed. The bonding material M2 may be heated to a predetermined temperature.

Further, the constituent materials of the first material to be bonded M1 and the second material to be bonded M2 to which the ultrasonic bonding method according to the present invention is applied are not limited to Al, and Sn, Ag, Au and the like may be used.

Further, in FIG. 2, the first step is performed by the first ultrasonic bonding machine 1A provided with the first ultrasonic horn H1, and the second step step is performed by the second ultrasonic bonding machine 1B provided with the second ultrasonic horn H2. However, the case is not limited to this, and for example, when an ultrasonic bonding machine capable of exchanging an ultrasonic horn is used, after performing the pre-stage step with the first ultrasonic horn H1, the first step is performed. The ultrasonic horn H2 may be replaced with the ultrasonic horn H2 to carry out the subsequent step.

1A ... 1st ultrasonic bonding machine 1B ... 2nd ultrasonic bonding machine A1 ... Anvil H1 (H1a to H1d) ... 1st ultrasonic horn H2 (H2a, H2b) ... 2nd ultrasonic horn 2 ... Vibration Child 3 ... Power supply 10 (10a-10e) ... Protrusion portion 15 ... Ultrasonic bonding machine main body 20 ... Curved portion 50 (50a) ... Plastic flow region 150 ... Interface C ... Adhesive nucleus M1 ... First material to be bonded M2 ... First 2 Material to be bonded 200 ... First indentation 300 ... Second indentation 500 ... Bonded body

Claims (7)

A process of making the joint portion of the first material to be joined and the joint portion of the second material to be opposed to each other and sandwiching them between the first ultrasonic horn and the anvil.
A step of forming adhesion nuclei at the interface between the joint portion of the first material to be joined and the joint portion of the second material to be joined by ultrasonically vibrating the first ultrasonic horn while applying pressure.
A step of sandwiching the first material to be joined and the second material to be joined between the second ultrasonic horn and the anvil in a state of being temporarily joined by the adhesion nucleus.
The second ultrasonic horn is ultrasonically vibrated while being pressurized to expand the plastic flow region at the interface between the joint portion of the first material to be joined and the joint portion of the second material to be joined. Process and
Have a,
The first ultrasonic horn has a protrusion on the pressurized surface and has a protrusion.
The adherent nucleus is formed corresponding to the protrusion and is formed.
The pressure surface of the second ultrasonic horn that comes into contact with the first material to be bonded or the second material to be bonded is configured so that the cross-sectional edge portion in the direction orthogonal to the vibration direction has a smooth curved portion. ultrasonic bonding method characterized by there. The ultrasonic wave according to claim 1, wherein the first ultrasonic horn is formed with a plurality of uneven portions on a pressure surface in contact with the first material to be bonded or the second material to be bonded. Bonding method. The super-superimposition according to claim 2, wherein the uneven portion is composed of a plurality of pyramidal or conical protrusions formed on the pressure surface and valleys formed between the protrusions. Ultrasonic bonding method. The ultrasonic bonding method according to claim 3, wherein the direction of the tip of the protrusion is inclined in a predetermined direction. The ultrasonic bonding method according to claim 1, wherein the smooth curved portion is formed of a part of an arc or a part of an ellipse. A claim characterized in that the relationship between the first energy E1 applied to the first ultrasonic horn and the second energy E2 applied to the second ultrasonic horn is E1 <E2. The ultrasonic bonding method according to any one of claims 1 to 5. A bonded body bonded by the ultrasonic bonding method according to any one of claims 1 to 6.
On the surface of the first material to be joined or the second material to be joined, a dot shape formed by the first ultrasonic horn is formed at a portion where the first ultrasonic horn and the second ultrasonic horn are pressure-contacted. A joint body characterized in that a linear second indentation by the second ultrasonic horn is superposed on at least a part of the first indentation of the above.

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