JP6824056B2 - Ultrasonic bonding device - Google Patents

Description

The present invention relates to ultrasonic bonding equipment, particularly, it relates to ultrasonic bonding equipment in which the heat flow from the bonding target portion upon joining of the joining target site was to monitor in heat flow sensor by the ultrasonic bonding apparatus.

The ultrasonic bonding device joins a bonding target portion by applying ultrasonic vibration and a load to the bonding target portion.

Conventionally, as an ultrasonic bonding device that monitors the temperature of a bonding target portion in order to determine the quality of bonding of the bonding target portion by the ultrasonic bonding device, the one disclosed in Patent Document 1 is known.

The ultrasonic bonding apparatus disclosed in Patent Document 1 includes a thermo camera that measures the temperature distribution of an ultrasonically bonded electrode tab, and the temperature between the unbonded region and the ultrasonically bonded region of the electrode tab where the temperature distribution is measured. It has a calculation unit that calculates the ultrasonic bonding region of the electrode tab using the difference, and calculates the ultrasonic bonding region of the electrode tab from the temperature distribution of the ultrasonically bonded electrode tab. It is configured to inspect the bonding condition of.

Further, in Patent Document 1, the temperature distribution of the electrode tab is measured discretely by measuring the temperature of one place of the electrode tab using a temperature sensor composed of a thermocouple instead of the thermo camera, which is simple. There is a description that it is possible to judge the quality of ultrasonic bonding.

However, the temperature monitor of the joint target part by the thermo camera has a problem that the device is expensive and complicated because the temperature analysis by the computer is required, and when a thermocouple is used, the arrangement part of the device is used. Since it is difficult to select and it is not possible to capture minute temperature changes depending on the thermocouple, it is not possible to monitor the temperature with high accuracy.

By the way, timer control, energy control, peak power control, and displacement control are known as ultrasonic oscillation control in this type of ultrasonic bonding device.

Here, the timer control is a control for stopping the ultrasonic oscillation that has reached a predetermined set oscillation time, the energy control is a control for stopping the ultrasonic oscillation that has reached a predetermined set oscillation time, and the peak power control is a control for stopping the ultrasonic oscillation that has reached a predetermined set oscillation time. , It is a control to stop the ultrasonic oscillation that has reached the predetermined set peak power, and the displacement control is the super that has reached the predetermined set displacement amount (depth amount (work sinking amount) and height amount (head absolute position)). This is a control to stop the ultrasonic oscillation.

However, timer control and displacement control set the set oscillation time and set displacement amount based on the past results of actual joining, for example, the average value when joining normally, and energy control and peak. Power control sets the set energy and set peak power based on the value consumed on the ultrasonic oscillator side, and is not necessarily controlled based on the energy consumed only for bonding at the bonding target site and peak power, so it is not necessarily reliable. There is a problem that the property is high and stable bonding quality cannot be obtained.

Japanese Unexamined Patent Publication No. 2008-14252

Therefore, according to the present invention, by monitoring the heat flow generated from the bonding target portion with a heat flow sensor and controlling the ultrasonic oscillation based on the detection output of the heat flow sensor, highly reliable and stable bonding quality can be obtained. and an object thereof is to provide an ultrasonic bonding equipment which is adapted.

In order to achieve the above object, in the invention of claim 1, a work including a joint target portion is placed on an anvil, a weight is applied to the joint target portion, and ultrasonic vibration is applied from an ultrasonic horn. An ultrasonic joining device for joining a joining target portion, which is provided at a position close to the joining target portion of the anvil and detects a heat flow from the joining target portion when the joining target portion is joined. In an ultrasonic joining device including an ultrasonic control means for monitoring the detection output of the heat flow sensor and stopping the ultrasonic vibration when the detection output of the heat flow sensor reaches a preset set value. The anvil has a heat flow sensor fixed structure embedded at a position close to the joint target portion, and the heat flow sensor fixed structure is arranged at a position close to the joint target portion and has a first peripheral edge. The thin first high thermal conductivity material body having the stepped portion, the heat flow sensor, and the heat flow sensor sandwiched between the portion of the first high thermal conductive material body excluding the first stepped portion. On the second step portion of the plate thickness second high thermal conductivity material body having the second step portion extending from the first step portion to the peripheral edge, and the second step portion of the second high thermal conductivity material body. A heat insulating material body provided on the periphery of the first high heat conductivity material body is provided, and the heat flow sensor is located between the first high heat conductivity material body and the second high heat conductivity material body. It is characterized in that it is fixedly arranged in.

The invention of claim 2 is the invention of claim 1, wherein the anvil is a first member having a mounting surface in the vicinity of the work mounting surface on which the work is mounted and having a mounting surface perpendicular to the work mounting surface. A second member that is attached to the first member so as to surround the mounting surface and has an upper surface having the same height as the first member, and the heat flow sensor comprises the first member. It is characterized in that it is pressed and attached to the attachment surface of the above by a pressing plate made of a highly heat-insulating and highly heat-resistant material.

The invention of claim 3 is characterized in that, in the invention of claim 1 or 2 , the ultrasonic horn applies a lateral ultrasonic vibration parallel to the bonding target portion.

The invention of claim 4 is characterized in that, in the invention of claim 1 or 2 , the ultrasonic horn applies ultrasonic vibration in a vertical direction perpendicular to the joint target portion.

The invention of claim 5 is the invention of any one of claims 1 to 4 , wherein the upper limit value and the lower limit value of the peak heat flow value detected by the heat flow sensor are set in advance, and the above-mentioned invention is performed when the joining target portion is joined. It is further characterized by further comprising a joining propriety determining means for determining whether or not joining is possible based on whether or not the peak heat flow value detected by the heat flow sensor is between the upper limit value and the lower limit value.

According to the present invention, a work including a joint target portion is placed on an anvil, a load is applied to the joint target portion, and ultrasonic vibration is applied from an ultrasonic horn to join the joint target portion. A device, which is provided at a position close to the joining target portion of the anvil, monitors a heat flow sensor that detects heat flow from the joining target portion when joining the joining target portion, and monitors the detection output of the heat flow sensor. In an ultrasonic joining device including an ultrasonic control means for stopping the ultrasonic vibration when the detection output of the heat flow sensor reaches a preset value, the anvil is attached to the joining target portion. A thin plate having a heat flow sensor fixed structure embedded at a close position, the heat flow sensor fixed structure is arranged at a position close to the joining target portion, and has a first step portion on the peripheral edge. The high thermal conductivity material body of No. 1, the heat flow sensor, and the heat flow sensor are sandwiched between a portion of the first high thermal conductivity material body other than the first step portion , and the peripheral edge from the first step portion. A second high thermal conductivity material body having a plate thickness extending to a second step portion, and the first high thermal conductivity material body on the second step portion of the second high thermal conductivity material body. A heat insulating material body provided on the peripheral edge thereof is provided, and the heat flow sensor is fixedly arranged between the first high thermal conductivity material body and the second high thermal conductivity material body. Since it is configured, it has the effect of obtaining high reliability and stable bonding quality.

FIG. 1 is a diagram showing an outline of Example 1 of an ultrasonic bonding device according to the present invention. FIG. 2 is a cross-sectional view and a top view showing details of the heat flow sensor fixed structure used in the ultrasonic bonding apparatus shown in FIG. FIG. 3 is a top view showing details of other configurations of the anvil used in the ultrasonic bonding apparatus shown in FIG. 1 and a sectional view thereof AA. FIG. 4 is a front view of the anvil with the second member shown in FIG. 3 removed. FIG. 5 is a flowchart showing a control example of the ultrasonic bonding apparatus shown in FIG. FIG. 6 is a diagram showing an outline of Example 2 of the ultrasonic bonding device according to the present invention.

Hereinafter, examples for carrying out the present invention will be described in detail with reference to the attached drawings.

FIG. 1 is a diagram showing an outline of Example 1 of an ultrasonic bonding device according to the present invention.

In FIG. 1, in the ultrasonic bonding apparatus 100 of the first embodiment according to the present invention, a work 30 including a bonding target portion 33 is placed on an anvil 20 fixed to a pedestal 10, and the bonding target portion 33 of the work 30 is placed. By applying a load from a weighting device (not shown) and applying ultrasonic vibration from the head 41 at the tip of the ultrasonic horn (hereinafter, simply referred to as a horn) 40, the work 30 is joined to the bonding target portion 33, that is, the work 31. The work 31 and the work 32 are joined at the surface in contact with the work 32.

The horn 40 is connected to an ultrasonic oscillator (hereinafter, simply referred to as an oscillator) 60 via a cone 50, and the ultrasonic vibration of the oscillator 60 is controlled by an ultrasonic oscillator 70. Here, the ultrasonic vibration applied from the head 41 at the tip of the horn 40 to the joining target portion 33 of the work 30 is a vibration in the lateral direction X parallel to the joining target portion 33. This ultrasonic bonding using ultrasonic vibration in the lateral direction X is suitable for, for example, metal-to-metal bonding, plastic welding bonding, particularly welding bonding of thin plastic sheets or films.

In the ultrasonic bonding apparatus 100 of the first embodiment, the heat flow sensor 83 monitors whether or not the bonding target portion 33 of the work 30 is in a bonding state.

The heat flow sensor 83 is a sensor that detects the flow rate and direction of thermal energy, and has significantly higher sensitivity to temperature changes than thermocouples widely used in conventional product development and evaluation, and dissipates heat and absorbs heat. It is possible to detect the heat flow in the direction of.

The heat flow sensor 83 is a well-known semiconductor heat flow sensor that outputs a voltage signal corresponding to the heat energy passing through the unit area per unit time, and the polarity of the voltage signal corresponds to the direction in which the heat energy passes, for example. , Bismus-Teruru heat flow sensor can be used.

By the way, in the ultrasonic bonding apparatus 100 of the first embodiment, the heat flow generated from the bonding target portion 33 at the time of bonding the bonding target portion 33 of the work 30 is fixed to the heat flow sensor which is embedded in the anvil 20 and shows details in FIG. It is monitored by a heat flow sensor 83 fixed by the structure 80.

As shown in FIG. 2A, the heat flow sensor fixed structure 80 has a heat flow sensor 83 between the thin first high thermal conductivity material 81 and the thick second high thermal conductivity material 82. It has a structure that is fixed by sandwiching.

The heat flow sensor fixed structure 80 is a thin first high thermal conductivity material body which is arranged in the anvil 20 near a joint target portion 33 of the work 30 and has a first step portion 81a on the peripheral edge. A second second step portion 81, which sandwiches the heat flow sensor 83, the heat flow sensor 83, and a portion of the first high thermal conductivity material body 81 other than the first step portion 81a , and extends from the first step portion 81a to the peripheral edge. On the second high thermal conductivity material body 82 having the stepped portion 82a and the second stepped portion 82a of the second high thermal conductivity material body 82, on the peripheral edge of the first high thermal conductivity material body 81. The heat flow sensor 83 is attached to the first step portion 82a of the second high thermal conductivity material body 82 by screwing the heat insulating material body 84 to the second step portion 82a of the second high thermal conductivity material body 82. It has a structure fixed between the high thermal conductivity material body 81 and the second high thermal conductivity material body 82.

Here, FIG. 2A shows the space between the heat insulating material body 84 and the heat flow sensor 83 and between the heat insulating material body 84 and the upright surface of the first step portion 81a of the first high thermal conductivity material body 81. As shown in, a gap is provided. This void is provided to reduce the heat diffusion to the heat insulating material body 84 as much as possible.

The first high thermal conductivity material body 81 and the second high thermal conductivity material body 82 can be formed by using a high thermal conductivity material body such as copper, aluminum, and graphite, and the heat insulating material body 84 is a resin. It can be formed using a heat insulating material of the system.

Further, as shown in FIG. 2B, the screws 85 are provided at the four corners of the heat flow sensor fixed structure 80, and the heat flow sensor 83 is made of a heat insulating material by the four screws 85 provided at the four corners. It is sandwiched and fixed between the first high thermal conductivity material body 81 and the second high thermal conductivity material body 82 via 84. The terminal 83a is for extracting the voltage signal output from the heat flow sensor 83.

According to such a configuration, the heat flow sensor 83 is sandwiched and fixed between the thin plate first high thermal conductivity material body 81 and the plate thickness second high thermal conductivity material body 82, and is fixed to the first plate. Since the high thermal conductivity material body 81 and the second high thermal conductivity material body 82 are insulated by the heat insulating material body 84,
Damage due to pressurization from the outside of the heat flow sensor 83 can be prevented, and the heat flow from the first high thermal conductivity material 81 side can be detected with high accuracy.

The heat flow sensor fixed structure 80 having the above configuration increases the temperature difference between the front and back surfaces of the heat flow sensor 83, and increases the detected value of the heat flow rate Q (W / m2) detected by the heat flow sensor 83.

That is, since the first high thermal conductivity material 81 of the heat flow sensor fixed structure 80 has a small volume and a small thickness, the heat generated at the joint target portion 33 does not diffuse to the surroundings, and the heat flow sensor 83 Heat can be efficiently collected on the surface. Further, since the second high thermal conductivity material body 82 has a large volume and a large thickness, the amount of heat that has passed through the heat flow sensor 83 is immediately radiated and diffused to the surroundings to prevent the temperature rise on the back surface side of the heat flow sensor 83. It works.

FIG. 3 is a top view showing details of other configurations of the anvil 20 used in the ultrasonic bonding apparatus shown in FIG. 1 and a sectional view thereof AA. Further, FIG. 4 is a front view of the anvil 20 with the second member 22 shown in FIG. 3 removed.

In FIGS. 3 and 4, the anvil 20 in this case is composed of a first member 21 and a second member 22, and has a knurled work mounting surface 21a on the upper surface of the first member 21. The work mounting block 21b is detachably attached. Here, the work mounting block 21b is replaced when the knurled portion of the work mounting surface 21a deteriorates.

Further, the heat flow sensor 83 is mounted on the mounting surface of the first member 21 in the vicinity of the work mounting surface 21a and perpendicular to the work mounting surface 21a. Here, in the mounting of the heat flow sensor 83 on the mounting surface of the first member 21, the heat flow sensor 83 is pressed by the pressing plate 24, and the pressing plate 24 is fixed to the mounting surface of the first member 21 by the screws 25a and 25b. It is done by. As the holding plate 24 for holding the heat flow sensor 33, a resin plate made of a highly heat-insulating and highly heat-resistant material can be used. A slit 22a is formed in the lower portion of the second member 22, and the output wiring of the heat flow sensor 83 is led out to the outside through the slit 22a.

FIG. 5 is a flowchart showing a control example of the ultrasonic bonding apparatus shown in FIG.

In this control example, first, the horn 40 is lowered (step 401), and it is examined whether the head 41 at the tip of the horn 40 has come into contact with the work 30 (step 402). Here, if the head 41 is not in contact with the work 30 (NO in step 402), the process returns to step 401 and the head continues to descend.

When it is determined in step 402 that the head 41 has come into contact with the work 30 (YES in step 402), weighting is started on the joint target portion 33 of the work 30 (step 403), and the work 30 is contacted with the joint target portion 33. With the load applied, the ultrasonic oscillator 70 is controlled to start applying ultrasonic vibration to the joint target portion 33 of the work 30 (step 404).

Then, the output of the heat flow sensor 83 is monitored, and it is checked whether the output of the heat flow sensor 83 has reached a preset set value (step 405). Here, if the output of the heat flow sensor 83 does not reach the preset value (NO in step 405), the application of ultrasonic vibration to the joint target portion 33 of the work 30 is continued.

When it is determined in step 405 that the output of the heat flow sensor 83 has reached the set value (YES in step 405), the ultrasonic oscillator 70 is controlled and applied to the joint target portion 33 of the work 30. Stop the ultrasonic vibration (step 406).

Next, it is examined whether the peak heat flow value detected from the output of the heat flow sensor 83 is between the preset upper limit value and the lower limit value (step 407). Here, when the peak heat flow value is between the upper limit value and the lower limit value (YES in step 407), it is determined that the joining of the joining target portion 33 of the work 30 is properly completed, and the joining target portion of the work 30 is determined. The load on 33 is released (step 408), the horn 40 is raised, and this joining process is completed.

If the peak heat flow value is not between the upper limit value and the lower limit value in step 707, an abnormality alarm is issued as a joining failure (step 410), the process proceeds to step 408, and the load on the joining target portion 33 of the work 30 is released. (Step 408), the horn 40 is raised to end this joining process.

According to the above configuration, if the bonding target portion 33 of the work 30 can be appropriately bonded by the ultrasonic bonding device 100, and the bonding target portion 33 of the work 30 is not optimally bonded, an alarm can be issued. it can.

In the first embodiment, the case where the ultrasonic vibration applied from the horn 40 to the joint target portion 33 of the work 30 is the vibration in the lateral direction X parallel to the joint target portion 33 is shown. The present invention can be similarly applied to the case where the ultrasonic vibration applied from the horn 40 to the joint target portion 33 of the work 30 is a vibration in the vertical direction Y perpendicular to the joint target portion 33. it can.

FIG. 6 is a diagram showing an outline of Example 2 of the ultrasonic bonding device according to the present invention. In the ultrasonic bonding device 200 shown in FIG. 6, the parts having the same functions as the ultrasonic bonding device 100 shown in FIG. 1 are designated by the same reference numerals for convenience of explanation, and detailed description thereof will be omitted.

In the ultrasonic bonding apparatus 200 shown in FIG. 6, as shown in FIG. 6, a work 30 including a bonding target portion 33 is placed on an anvil 20 fixed to a pedestal 10, and the work 30 is placed on the bonding target portion 33 of the work 30. By applying a load from a weighting device (not shown) and applying ultrasonic vibration from the horn 40, the work 31 and the work 32 are joined at the bonding target portion 33 of the work 30, that is, the surface where the work 31 and the work 32 are in contact with each other. To do.

Here, in the ultrasonic bonding apparatus 200 of the second embodiment, vibration in the vertical direction Y perpendicular to the bonding target portion 33 is applied from the head 41 at the tip of the horn 40. This ultrasonic bonding using ultrasonic vibration in the longitudinal direction Y is suitable for, for example, fusion bonding to a resin.

Also in the ultrasonic bonding apparatus 200 of the second embodiment, the heat flow from the bonding target portion 33 of the work 30 is generated by the heat flow sensor 83 fixed by the heat flow sensor fixed structure 80 embedded in the anvil 20 and shown in detail in FIG. Be monitored.

Other configurations are the same as those of the ultrasonic bonding device 100 shown in FIG.

The present invention is not limited to the above-described embodiment, and many modifications can be made by ordinary creative abilities of those skilled in the art within the scope of the technical idea of the present invention.

Also in the ultrasonic bonding apparatus 200 of the second embodiment, the heat flow sensor 83 may be attached to the anvil 20 as shown in FIGS. 3 and 4.

Further, the determination as to whether or not the joint portion can be joined using the peak heat flow value according to the present invention is similarly applied to the case where timer control, energy control, peak power control, and displacement control are used as ultrasonic oscillation control. Can be done.

The present invention is not limited to the above-described embodiment, and many modifications can be made by ordinary creative abilities of those skilled in the art within the scope of the technical idea of the present invention.

10 ... Pedestal 20 ... Anvil 21 ... First member 21a ... Work mounting surface 21b ... Work mounting block 22 ... Second member 24 ... Holding plate 30 ... Work 40 ... Horn 41 ... Head 50 ... Cone 60 ... Transducer 70 ... Ultrasonic oscillator 80 ... Heat flow sensor fixed structure 81 ... First high thermal conductivity material 82 ... Second high thermal conductivity material 83 ... Heat flow sensor 84 ... Insulation material 100 ... Ultrasonic bonding device 200 ... Ultrasonic bonding device

Claims (5)

An ultrasonic bonding device that places a work including a bonding target site on an anvil, applies a load to the bonding target site, and applies ultrasonic vibration from an ultrasonic horn to bond the bonding target site.
A heat flow sensor provided at a position close to the joining target portion of the anvil and detecting a heat flow from the joining target portion when joining the joining target portion,
An ultrasonic control means that monitors the detection output of the heat flow sensor and stops the ultrasonic vibration when the detection output of the heat flow sensor reaches a preset value.
In an ultrasonic bonding device equipped with
The anvil
It has a heat flow sensor fixed structure embedded in a position close to the joint target site, and has
The heat flow sensor fixed structure is
A thin first high thermal conductivity material body which is arranged in a position close to the joint target portion and has a first step portion on the peripheral edge.
With the heat flow sensor
A second plate thickness having a second step portion extending from the first step portion to the periphery by sandwiching the heat flow sensor with a portion of the first high thermal conductivity material body other than the first step portion . With high thermal conductivity material
A heat insulating material body provided on the periphery of the first high thermal conductivity material body on the second step portion of the second high thermal conductivity material body, and a heat insulating material body.
Equipped with
The heat flow sensor is
An ultrasonic bonding apparatus characterized in that it is fixedly arranged between the first high thermal conductivity material body and the second high thermal conductivity material body. The anvil
A first member having a mounting surface in the vicinity of the work mounting surface on which the work is placed and perpendicular to the work mounting surface, and
A second member that is attached to the first member so as to surround the mounting surface and has an upper surface having the same height as the first member.
Equipped with
The heat flow sensor is
The ultrasonic bonding apparatus according to claim 1, wherein the ultrasonic bonding apparatus is mounted on the mounting surface of the first member by being pressed by a pressing plate made of a highly heat-insulating and heat-resistant material. The ultrasonic horn
The ultrasonic bonding apparatus according to claim 1 or 2, wherein a lateral ultrasonic vibration parallel to the bonding target portion is applied. The ultrasonic horn
The ultrasonic bonding apparatus according to claim 1 or 2, wherein ultrasonic vibration in a vertical direction perpendicular to the bonding target portion is applied. The upper and lower limits of the peak heat flow value detected by the heat flow sensor are set in advance.
A means for determining whether or not joining is possible based on whether or not the peak heat flow value detected by the heat flow sensor is between the upper limit value and the lower limit value when joining the joining target portion.
The ultrasonic bonding apparatus according to any one of claims 1 to 4, further comprising.

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