JPH03183527A - Ultrasonic joining equipment - Google Patents

Abstract

PURPOSE:To enable joining effectively with high reliability by a method wherein, a high energy is imparted to the first member at the initiation of joining while a control means is provided to decrease the magnitude of ultrasonic vibration in accordance with the length of time, and after a preset time is elapsed, the given energy is decreased in strength in order to lower the given energy. CONSTITUTION:A semiconductor chip 23 is provided between a pressing face 7a and a substrate 2 in the manner that the electrode 23a faces right against the electrode 21a. On the under-surface of the electrode 23a, a conductive film adhesive 22 is temporarily pasted. The data of the inputted program to be started are: an initial amplitude xsi11 of an electric signal by the supersonic oscillator 9 a time length t11 which maintains said amplitude at xsi11; the amplitude xsi12(xsi11>xsi12) after the elapse of time t11; the time length t12 necessary for maintaining the amplitude of the signal at xsi12; and time length t13 for press- fit the semiconductor 23 after the elapse of time t12. The optimum value of the above mentioned data are previously determined based upon the nature and the thickness of the semiconductor chip to be joined, composition of conductive film adhesive 22 and the like, and these values are inputted by the control of the operation part 11.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to an ultrasonic bonding device for bonding two members by ultrasonic vibration.

B. Conventional technology For example, when bonding a semiconductor chip (first member) to a substrate (second member), the electrodes of the semiconductor chip to which a film adhesive is temporarily attached are pressed against the electrodes on the substrate while superposition is applied. One possible method is to apply sonic vibrations. In this case, due to the pressure load and ultrasonic vibration, ultrasonic energy is applied to the film adhesive through the semiconductor chip, causing it to heat up and melt, thereby joining the electrodes on the semiconductor chip to the electrodes on the substrate. This ultrasonic energy is proportional to the product of the load acting on the adhesive during pressing, the amplitude of the ultrasonic vibration, and the frequency of the ultrasonic vibration.

FIG. 13(b) shows the temperature change of the film adhesive when performing the above-mentioned ultrasonic bonding, where To represents the temperature at which the adhesive begins to melt, and T1 represents the temperature at which the adhesive begins to burn. There is. Here, if the adhesive burns, the bonding strength will be weakened, so when performing ultrasonic bonding, it is necessary to maintain the temperature of the adhesive at a temperature below T.

Now, if an ultrasonic vibration of amplitude ξ (Figure I3 (a)) is applied while pressing the semiconductor chip against the substrate with a constant load,
The temperature of the adhesive increases as shown by Q4, and reaches the melting temperature T after time t0 has elapsed. reach. After that, the temperature rose further,
If the ultrasonic vibration is canceled before the temperature T1 is reached, the temperature starts to drop and solidification starts at T.

Next, with the same load as above, the amplitude ξ is smaller than the amplitude ξ1.
The case where ultrasonic vibration of 2 (FIG. I3(a)) is applied will be explained. The frequency of the ultrasonic vibration at this time is the same as described above. In this case.

As the amplitude becomes smaller, the energy due to ultrasonic vibration is reduced compared to the above, and the temperature of the adhesive decreases to Q2 from the start of bonding.
As shown by , the melting temperature T increases more slowly than described above and after time t1 has elapsed. reach. After that, the temperature increases further,
If the ultrasonic vibration is canceled before the temperature T1 is reached, the temperature starts to decrease and solidification starts at To.

Problems to be Solved by the C0 Invention However, in both of the above two examples, since the energy is constant, each has the following problems. In other words, in the former case (Q), where the amplitude of the ultrasonic vibration is increased to increase the energy, the temperature of the adhesive becomes To and To
The time t2 maintained between the two is shorter than the latter, so that the adhesive is not sufficiently melted and the bonding strength of the semiconductor chip to the substrate is weakened. On the other hand, in the latter case (Q2), the time period during which the temperature of the adhesive is maintained between To and T is 1. Since the length is longer than the former, the adhesive is sufficiently melted and there is no problem with adhesive strength, but it takes a long time to join.

A technical problem of the present invention is to efficiently perform highly reliable bonding by increasing the energy at the start of bonding and decreasing it thereafter when performing ultrasonic bonding.

01 Means for Solving the Problems The present invention will be explained with reference to FIG. 1A, FIG. 5, and FIG. 8 showing an embodiment of the present invention. Ultrasonic oscillator 9 that generates
(40), an ultrasonic vibration transmitter 7 that transmits ultrasonic vibrations to the first member 23, and a pressing means that presses the second member 23 (onto the second member 2) using the ultrasonic vibration transmitter 7. 4
(32°33), and by pressing the first member 23 while applying ultrasonic vibration, the first member 23 is moved to the second
It is applied to ultrasonic bonding equipment that joins two parts.

As shown in FIG. 1A, the invention of claim 1 applies high energy to the first member 23 at the start of bonding, and reduces this energy after a predetermined time has elapsed, so that the amplitude of the ultrasonic vibration is reduced to 1 hour. A control means 10 is provided which is made correspondingly smaller.

Further, the invention of claim 2 provides a displacement detecting means 4 for detecting the displacement of the ultrasonic vibration transmitter 7 in the pressing direction, as shown in FIG.
1, and a control means 38 that applies high energy to the first member 23 at the start of joining and controls the displacement based on the output of the displacement detection means 41 in order to reduce this energy after a predetermined period of time has elapsed.

Furthermore, as shown in FIG. 8, the invention of claim 3 includes a load detecting means 5Y that detects the load acting on the first member 23 during pressing, and a load detecting means 5Y that applies high energy to the first member 23 at the time of starting joining. , and a control means 52 that reduces the load in accordance with time based on the output of the load detection means 51 in order to reduce this energy after a predetermined time has elapsed.

R0 effect In the invention of claim 1, the control means 10 reduces the amplitude of the ultrasonic vibration according to time. Therefore, high energy is applied to the first member 23 at the start of bonding, and the bonding time is shortened. After a predetermined period of time, this energy is lowered so that, for example, the adhesive 22 can be bonded in one minute without becoming undesirably hot.

Further, in the invention of claim 2, the displacement detecting means 41 detects the displacement of the ultrasonic vibration transmitting body 7 in the pressing direction, and the controlling means 38 applies high energy to the first member 23 at the time of starting welding to a predetermined level. After time has elapsed, the displacement is controlled to reduce this energy. This provides a similar effect.

Furthermore, in the invention of claim 3, the load detection means 51 is
The control means 52 detects the load acting on the first member 23 during pressing, and controls the load so as to apply high energy to the first member 23 at the start of joining, and to reduce this energy after a predetermined period of time has elapsed. becomes smaller depending on the time.

In addition, in the above-mentioned section and section E which explain the present invention in detail, figures of the embodiment are used in order to make the present invention easier to understand, but the present invention is not limited to the embodiment.

F. Example Hereinafter, a case will be described in which the present invention is applied to an ultrasonic bonding apparatus used for bonding a semiconductor chip and a substrate.

- First Embodiment - Figures 1A to 4 explain an ultrasonic bonding apparatus according to the invention of claim 1, and Figure 1A shows an ultrasonic bonding device in which the amplitude of the electric signal of the ultrasonic oscillator 9 is controlled. The overall configuration of a device for adjusting sound wave vibration energy is shown. Compressed air from a pneumatic source 1 is guided through a switching valve 2 to a pneumatic cylinder 4 fixed to the upper part of a frame 3. The switching valve 2 can be switched between a communicating position A in which the compressed air is guided to the cylinder 4 and a blocking position B in which the compressed air is blocked. A case 5 is connected to the tip of the piston rod 4a of the cylinder 4, and the case 5 holds a vibrator 6 and an ultrasonic vibration transmitter 7. Note that 8 is a pressure control valve that controls the pressure introduced into the cylinder 4, and 4b is a return spring that drives the extended piston rod 4a to the initial position.

The vibrator 6 is connected to an ultrasonic oscillator 9 controlled by a control circuit (control means) IO. This ultrasonic oscillator 9 has control terminals VCON, 0N-OFF, as shown in FIG.
, and the ON/OFF terminal from the control circuit 10 is connected to the terminal 0N-OFF.
At the same time as the off signal is input, a voltage is applied to the terminal VCON from the control circuit O. If a voltage is applied while the ON signal is being input, an electrical signal with an amplitude corresponding to the voltage is generated. This voltage and amplitude have, for example, a proportional relationship. The vibrator 6 converts the electrical signal from the ultrasonic oscillator 9 into ultrasonic vibrations.

The control circuit -O is also connected to the operating member 11- and the above-mentioned switching valve 2, and by switching and controlling the switching valve 2, the expansion and contraction of the cylinder 4 is controlled. The operating member 11 is used to input various data (described in detail later) when performing ultrasonic bonding.

A substrate (second member) 21 on which an electrode 21a is formed is placed on a pedestal 12 (FIG. 1A) disposed below the ultrasonic vibration transmitter 7, and a thermoplastic material is attached to the electrode 21a. A semiconductor chip (No. I
The electrode 23a of the member) 23 is joined.

Next, the operation of the embodiment will be explained with reference to FIGS. 3 and 4.

When bonding the semiconductor chip 23, as shown in FIG. 1B, the substrate 21 is first placed on the pedestal 12 so that its electrode 21a faces the pressing surface 7a of the ultrasonic vibration transmitter 7, and then The semiconductor chip 23 is arranged between the pressing surface 7a and the substrate 21 so that its electrode 23a faces the electrode 21a. It is assumed that a conductive film adhesive 22 is temporarily attached to the lower surface of the electrode 23a. For example, when the power is turned on in this state, the program shown in FIG. 3 is activated within the control circuit 10. This program is based on the control circuit 10
This shows the procedure for ultrasonic bonding processing performed at the machine, and after startup, the system waits for input of various data.

The input data includes the initial amplitude ξ, 1 of the electric signal from the ultrasonic oscillator 9, the time txt for holding the amplitude of this electric signal at ξ8, and the amplitude ξ1□ (ξ1.
〉ξ, 2), time L to maintain the amplitude of the electrical signal at ξ1□
Step 2 and time t to press the semiconductor chip 23 after time t□2 has elapsed. The optimum values of these data are determined in advance based on the material and thickness of the semiconductor chip 23 to be bonded and the composition and thickness of the conductive film adhesive 22, and these values are determined by the operation of the operating member 11. Input by

The control circuit 10 reads the data input in step S1.

Here, FIG. 4(a) shows the temporal change in the amplitude of the electric signal generated by the ultrasonic oscillator 9, and FIG. 4(b) shows the temporal change in the temperature of the conductive film adhesive 22. It shows. The following description will be made with reference to FIGS. 4(a) and 4(b).

After inputting the data and performing the start operation, the process advances to step S2.
In step S2, the switching valve 2 is switched to the communication position hole, an on signal is output to the terminals 0N-OFF of the ultrasonic oscillator 9, and a predetermined voltage is applied to the terminal V C6N to increase the amplitude ξ8.
．． (time point P1□ in FIG. 4).

By the switching operation of the switching valve 2, compressed air from the pneumatic source is guided to the cylinder 4, the piston rod 4a is extended, and the vibrator 6 and the ultrasonic vibration transmitter 7 held in the case 5 are lowered together. , the pressing surface 7a of the ultrasonic vibration transmitter 7 presses the semiconductor chip 23 against the substrate 21. Specifically, the semiconductor chip 23 to which the conductive film adhesive 22 is temporarily attached
The electrode 23a of is pressed against the electrode 21a of the substrate 2↓. At the same time, the electric signal of amplitude ξ1 generated by the ultrasonic oscillator 9 is converted into mechanical ultrasonic vibration by the vibrator 6,
This ultrasonic vibration is magnified by the ultrasonic vibration transmitter 7 and transmitted to the semiconductor chip 23 and the conductive film adhesive 22.

As a result, a predetermined amount of energy is applied to the conductive film adhesive 22, causing it to generate heat, and as shown in FIG. 4(b), its temperature rises rapidly, reaching the melting temperature T. It starts melting when it reaches . In step S3, the process waits until time t has elapsed from time point P□, and then proceeds to step S4. In step S4, the voltage applied to the terminal V CON is lowered, and the amplitude of the electric signal from the ultrasonic oscillator 9 is reduced to ξ1□
The value ξ1□ is set to be smaller than (time P1□). As a result, the energy applied to the conductive film adhesive 22 is reduced, and its temperature reaches the temperature T. and T1. Here, TI is the temperature at which the conductive film adhesive 22 burns.

After that, in step S5, from time P l 2 to time t1□
Wait until the time elapses, and after that, the terminal is set to 0N in step S6.
- Outputs an off signal to OFF to cancel ultrasonic vibration (
Time point P, 3). As a result, the conductive film adhesive 22
temperature decreases to the melting temperature T.

Coagulation begins when the temperature drops below . After that, in step S7, wait until time t□3 has elapsed from time point P□, and after that,
In step S8, the switching valve 2 is switched to the cutoff position B, and the process is ended. This time tx'a is set longer than the time required for the adhesive 22 to drop to temperature T2 at which it completely solidifies. As the switching valve 2 is switched to the cutoff position B, the spring 4
The ultrasonic vibration transmitter 7 rises due to the spring force b and returns to the initial position.

According to the above procedure, the temperature of the adhesive 22 is T from time 1 P□ to P step 2 because the amplitude ξ, 2 of the ultrasonic vibration is large. and T, that is, the temperature at which the adhesive 22 melts and does not burn, increases rapidly from point P I□ to 1
), J has a small amplitude of 512.

The temperature is held between 'ro and 1' for a time L□2.

This time L1□ is sufficient time for the adhesive to completely melt. Therefore, according to the above method, bonding can be performed in a short time without reducing the adhesive strength.

In the above description, the amplitude of the ultrasonic vibration is controlled in two stages, but various methods of this control can be considered depending on the material, strength, etc. of the adhesive used.

That is, control 1 may be used in three or more steps, or the amount may be decreased smoothly instead of stepwise.

1. Second Embodiment Next, based on FIGS. 5 to 7, the ultrasonic vibration transmitting body 7
A second embodiment will be described in which the ultrasonic vibration energy is adjusted by controlling the displacement of the ultrasonic vibration.

FIG. 5 shows the overall configuration of the ultrasonic bonding device according to the invention of claim 2, and the same parts as in FIG.
It is attached.

The motor 3 is attached to the second part of the holding frame 31 attached to the fixed surface.
2 is installed, and one end of a screw stud 33 is connected to the output shaft of this motor 32. The screw stud 33 screws through the three naso 1-35 attached to the moving table 34 and extends downward, and the other end is rotatably supported by the T section of the holding frame 31. There is. The movable table 34 is stopped from rotating by a nut 35 of I: 'l; which is stopped by a linear guide 31a on a fixed surface. Therefore, when the screw stud 33 is rotated by the driving force of the motor 32, the movable table 34 moves up and down. Mobile table 34
Also, brackets 1-36 and 37 are attached to two locations on the second part of j, and the above-mentioned vibrator G is attached to the bracket 36.
However, the ultrasonic vibration transmitting bodies 7 are held by the brackets 37, respectively.

Chiyo 32 is connected to a motor drive circuit 39 that is controlled by a control circuit 38 , and the motor drive circuit 39 is connected to the control circuit 3
The screw head 33 is rotationally driven by the motor 32 based on the command from 8. The control circuit 38 also includes an ultrasonic oscillator 4.
0 and an encoder (displacement detection means) 41 are connected,
Ultrasonic oscillator 40 generates an electrical signal of constant amplitude in response to an on signal from control circuit 38. encoder 41
Is the drive of motor 32! ! The number of pulses a7 corresponding to the amount of llI is generated and inputted to the control circuit 38, and the control circuit: 3
8 calculates the displacement of the ultrasonic signal transmitter 7 in the pressing direction by counting the number of pulses. This displacement is the displacement when the ultrasonic vibration transmitting body 7 is located at the top, which is zero, and the lower the ultrasonic vibration transmitting body 7 is, the larger the displacement becomes. 2. Next, the operation of this embodiment will be explained based on FIGS. 6 and 7.

Similarly to the above, the substrate 21 is connected to its electrodes 21. Place it on the pedestal 12-H so that the ultrasonic vibration transmitter 7 faces the ultrasonic vibration transmitter 7.
Next, the semiconductor chip 23 is placed between the pressing surface 7a and the substrate 21 so that its electrode 23a faces the ffi pole 21a. When the power is turned on in this state, the program shown in FIG. 6 is started, and the system waits for data input as described above. In this embodiment, the ultrasonic vibration energy is adjusted by controlling the displacement of the ultrasonic vibration transmitter 7, and the input data is an initial displacement of 1.21, a time tzt for pressing at this initial displacement, and a time. Displacement L2□ after t21 and displacements 1, 2. The pressing time is t2□. These pigs are input by operating the operating member 1■, and step 5
It is read into the control circuit 38 at l-1-.

Next, when the start operation is performed, the process proceeds to step s12, where the displacement of the ultrasonic vibration transmitter 7 is set to the initial displacement L2□, and the screw thread 33 is set by the motor 32 via the motor drive circuit 39.
is rotated in a predetermined direction and the process proceeds to step S13. The rotation of the screw stud 33 causes the movable table 34 to descend, and the vibrator 6 and the ultrasonic vibration transmitter 7 to move down together. As a result, the conductive film adhesive 22 is pressed by the pressing surface 7a.
The electrode 23a of the semiconductor chip 23 to which is temporarily attached is connected to the substrate 2.
1 electrode 21a. In step S13, wait until the displacement reaches ■,21, and when it reaches Lz, stop the motor 32 in step S], 4, and proceed to step S1.
Proceed to step 5. Whether the displacement has reached L21 is determined based on whether the number of pulse signals from the encoder 41 has reached a predetermined value.

Here, FIG. 7(a) shows the conductive film adhesive 22.
FIG. 7(b) shows temporal changes in the displacement of the ultrasonic vibration transmitter 7 (broken line) and the load acting on the semiconductor chip 23 (solid line).

The control circuit 38 outputs an on signal to the ultrasonic oscillator 40 at time P21 in FIG. 7(a) to generate an electric signal of a predetermined amplitude (step 515). This electrical signal is converted into mechanical ultrasonic vibration by the vibrator 6, and transmitted to the semiconductor chip 23 and the conductive film adhesive 22 via the ultrasonic vibration transmitter 7. As a result, a predetermined energy is applied to the conductive film adhesive 22, as shown in FIG. 7(a).
As shown by the broken line in , the temperature rises rapidly from time point P2□ and reaches temperature T. It starts melting when it reaches .

In addition, as the temperature rises, the conductive film adhesive 2
2 becomes soft, the load acting on the conductive film adhesive 22 decreases as shown by the solid line in FIG. 7(b). Accordingly, the energy applied to the adhesive 22 is reduced, the temperature rise of the adhesive 22 is suppressed, and the temperature reaches T as shown in FIG. 7(a). and T□.

In step 816, the process waits until time t2□ has elapsed from time point P21, and then proceeds to step S17. During this time t2□, the temperature T is the time required for the adhesive 22 to completely melt. The time to be maintained between the T-work and the T-work is set. In step S17, an off signal is output to the ultrasonic oscillator 40 to cancel the oscillation, and the motor 32 drives the screw stud 33 to further lower the ultrasonic vibration transmitter 7 in order to make the displacement the finishing displacement L2□. (Time point P2□). Next, in step 818, the process waits until the displacement reaches L2□, and when it reaches L2□ (time point P2), the motor 32 is stopped in step S19. As the ultrasonic vibration transmitter 7 descends at time P2□, the load acting on the conductive film adhesive 22 increases as shown in the figure, and when the displacement reaches L2□, it remains constant thereafter.

Next, in step S20, wait until time t22 has elapsed from time point P2□, and after that, in step S21, the motor 32
is driven to raise the ultrasonic vibration transmitting body 7 to the initial position, and the process ends (time point P24). This time t22 is set longer than the time for the adhesive 22 to completely solidify, that is, the time for it to reach the complete solidification temperature T2 (FIG. 7(a)).

According to the above procedure, ultrasonic vibration and initial displacement L2.
A predetermined energy is applied to the adhesive 22 due to the load caused by this, and its temperature rapidly rises from time point P21 to T. and T
It reaches temperatures between 1 and 1. As the temperature rises, the adhesive 22 gradually becomes softer, so the load gradually decreases, and as a result, the above-mentioned energy decreases and the temperature of the adhesive 22 reaches T. and T1 for a predetermined period of time. This predetermined time is sufficient time for the adhesive to completely melt, and the time t2□ is set in advance to ensure this predetermined time. Therefore, according to the above, the bonding time can be shortened without reducing the adhesive strength as described above. Further, in this embodiment, since the adhesive 22 is solidified at the finishing displacement L2□, the adhesive 22 is initially
Even if there are variations in the thickness, the thickness after bonding can be made constant.

In the above description, the displacement was controlled to be constant from time point P2□ to P2□, but it may be changed as appropriate depending on the material and amount of the adhesive.

-Third Embodiment- Next, a third embodiment of the present invention will be described based on FIGS. 8 to 2.

FIG. 8 shows the overall configuration of the ultrasonic bonding apparatus according to the third aspect of the invention, in which the lower part of the pedestal 12 is provided.

A load cell (load detection means) 51 is provided to detect the load acting on the semiconductor chip 23 and the conductive film adhesive 22 described above, and the detection results of the load cell 51 are input to the control circuit 52. . The other configurations are the same as those shown in FIG. 5, and their explanation will be omitted.

FIGS. 9 and 10 show the joining processing procedure performed within the control circuit 52. When the power is turned on, this program is activated and waits for data input.

In this embodiment, the ultrasonic vibration energy is adjusted by controlling the load applied to the adhesive 22, and the input data includes an initial load F0, a load F2 smaller than this initial load F1, and a load F□ to F2, and further this l? The time t is held at 2, the time ty2 is held at 1, the finishing displacement, and the displacement L1. These data are manually input by operating the operating member 1]-, and are read into the control circuit 52 in step S31.

In step S32, the screw 33 is rotated by the motor 32 to apply an initial load F1 to the adhesive 22, and the ultrasonic vibration transmitter 7 is lowered. As a result, as described above, the semiconductor chip 23 is pressed by the pressing surface 7a of the ultrasonic vibration transmitter 7
The electrode 23a of is pressed against the electrode 21a of the substrate 21. In step S33, the load acting on the conductive film adhesive 22 is read from the signal of the load cell 51.

Wait until this becomes Fl, and when it reaches F, step S
At 34, the motor 32 is stopped.

Here, FIG. 11(a) shows the conductive film adhesive 22.
Figure 11 (1)) shows the load (solid line) acting on the adhesive 22 and the change in temperature of the ultrasonic vibration transmitter 7 over time.
The displacement (dashed line) is shown.

The control circuit 52 outputs an on-signal to the ultrasonic oscillator 40 at point (3) 4 in FIG. 11(a) to generate an electric signal of a predetermined amplitude (step 535).

In step 336, it is determined whether the time Lv has elapsed since the time point P1. If step S36 is negative, the load is set to F in step S38.

1; It is determined from the output of the load cell 51.

If step S38 is negative, the process advances to step S37 to drive the motor 32, and then returns to step 836. If step S38 is affirmed, step S39 moves to motor 3.
2 and returns to step 836. If step 336 is affirmed, the process advances to step S40. This load control is
This is done according to a preset pattern. As a result, a predetermined energy is applied to the conductive film adhesive 22, and the temperature rapidly rises to a temperature T as shown by the broken line in FIG. 11(a). 7. Figure 11(b) shows an example in which the load reaches F2 before the time tit elapses, and then the apostasy is held at F2 until the time t31 elapses. As the load decreases, the energy decreases, and as it approaches F2, the temperature rise of the adhesive is suppressed, and as shown in FIG. 11(a) L:T. When , the energy becomes almost constant and is maintained at a temperature between ro and T. When the load is controlled to be constant at 2, the displacement of the ultrasonic transmitter 7 decreases due to the melting of the adhesive 22.
In Figure 1(b), the displacement increases.

After that, in step S40, the ultrasonic oscillator 40 receives 4771
No. 4 is output to cancel the ultrasonic vibration (time point P32), and at the same time, in step S41, the displacement of the ultrasonic vibration transmitting body 7 is set to 1-displacement L1, and the motor 32 is driven. In step 542 (FIG. 10), it is determined from the output of the encoder 41 whether or not the displacement has become L, and if it is negative, it waits until it is positive, and if it is positive, the motor 32 is stopped in step S43. The process advances to step S44. Step S4
In step S4, the process waits until time t has elapsed from point P32, and after that, in step S45, the ultrasonic vibration transmitter 7 is driven to the initial position and the process is ended.

According to the procedure of Shio 42, the temperature of the conductive film adhesive 22 rapidly rises by 1 - from point P31. After that, by holding the load at F2, the temperature becomes T.

and T for a sufficient time to completely melt the adhesive. Therefore, according to the above, as described above, the bonding time can be shortened without reducing the adhesive strength.

In addition, after the ultrasonic vibration was canceled (time point P3□), the displacement of the ultrasonic vibration transmitter 7 was set to the finishing displacement ■, 1, so the thickness of the adhesive 22 was kept constant as described above. can do.

In addition, in the above, after the load is lowered to F2, it is controlled to be constant, but if the load is controlled as shown in FIG. 12(b), for example, as shown in FIG. 12(a), The temperature of the adhesive 22 can be kept constant between To and T1.

Further, in the above first to third embodiments, the case where the electrode 23a of the semiconductor chip 23 is bonded to the electrode 21a of the substrate 2 through the conductive film adhesive 22 has been described, but other members The present invention can also be applied to cases where a piezoelectric material for applying ultrasonic vibration is bonded to an acoustic lens used in an ultrasonic probe. Also, adhesive 2
2 is not used.

It can also be used when bonding the same type of resin to a thermoplastic resin.

G0 Effect of the invention According to the invention of claim 1, when joining a first member to a second member by applying ultrasonic vibration, high energy is applied to the first member at the start of joining, and the vibration is applied for a predetermined period of time. After the elapsed time, the amplitude of the ultrasonic vibration is reduced over time in order to reduce the energy, so for example, the temperature of the adhesive, which is the bonding medium for both parts, is quickly raised to the melting temperature, and the Allows for sufficient melting time,
This allows the bonding time to be shortened without reducing the bonding strength.

Further, according to the invention of claim 2, by controlling the displacement of the ultrasonic vibration transmitter, high energy is applied to the second member at the start of welding, and the energy is reduced after a predetermined time has elapsed. , the same effect as described above can be obtained.

Furthermore, according to the invention of claim 3, by controlling the load acting on the first member, high energy is applied to the first member at the start of joining, and the energy is reduced after a predetermined period of time has passed. So.

Effects similar to those described above can be obtained.

[Brief Description of the Drawings] Figures 1A to 4 show a first embodiment of the present invention;
Figure A is an overall configuration diagram of the ultrasonic bonding apparatus according to the invention of claim 1, Figure 1B is a partially enlarged view thereof, Figure 2 is a diagram explaining the configuration of the ultrasonic oscillator, and Figure 3 is a flowchart of the processing procedure. , FIG. 4(a) is a diagram showing the temporal change in the amplitude of ultrasonic vibration, and FIG. 4(b) is a diagram showing the temporal change in the temperature of the adhesive. 5 to 7 show a second embodiment of the present invention, and FIG. 5 is an overall configuration diagram of an ultrasonic bonding apparatus according to the invention of claim 2,
FIG. 6 is a flowchart of the processing procedure. FIG. 7(a) is a diagram showing temporal changes in the temperature of the adhesive and the amplitude of ultrasonic vibration, and FIG. 7(b) is a diagram showing temporal changes in the displacement and load of the ultrasonic vibration transmitting body. . 8 to 10 show a third embodiment of the present invention;
The figure is an overall configuration diagram of an ultrasonic bonding apparatus according to the invention of claim 3, FIGS. 9 and 10 are flowcharts of the processing procedure,
FIG. 11(a) is a diagram showing temporal changes in the temperature of the adhesive;
FIG. 11(b) is a diagram showing temporal changes in load and displacement of the ultrasonic vibration transmitter, FIGS. 12(a) and (b) show modified examples, and FIGS. 11(a) and (b) This is a diagram corresponding to . 3(a) and 3(b) are diagrams respectively showing temporal changes in the amplitude of ultrasonic vibration and adhesive temperature in conventional ultrasonic bonding. Engineering: Pneumatic source 2: Switching valve 4 Niji cylinder 6: Vibrator 7: Ultrasonic vibration transmitter 9.40: Ultrasonic oscillator 10.38, 52: Control circuit 11: Operation member 21: Substrate 21a: Electrode 22: Conductive adhesive film adhesive 23: semiconductor chip 23a: electrode 32: motor 33: screw thread 39: motor drive circuit

Claims (1)

[Scope of Claims] 1) A vibrator, an ultrasonic oscillator that generates an electric signal to cause the vibrator to vibrate ultrasonically, and an ultrasonic vibration transmitter that transmits the ultrasonic vibration to a first member. , a pressing means for pressing the first member against the second member using the ultrasonic vibration transmission body, and pressing the first member while applying the ultrasonic vibration to the first member, the first member is pressed. In an ultrasonic bonding device for bonding to a second member, high energy is applied to the first member at the start of bonding, and after a predetermined time elapses, the amplitude of the ultrasonic vibration is adjusted according to time in order to reduce the energy. An ultrasonic bonding device characterized by comprising a control means for reducing the size of the ultrasonic bonding device. 2) a vibrator, an ultrasonic oscillator that generates an electric signal for ultrasonic vibration of the vibrator, an ultrasonic vibration transmission body that transmits the ultrasonic vibration to a first member, and the ultrasonic vibration transmission a pressing means for pressing the first member against the second member with a body, and joining the first member to the second member by pressing the first member while applying the ultrasonic vibration. An ultrasonic bonding apparatus comprising: displacement detection means for detecting displacement of the ultrasonic vibration transmitter in the pressing direction; applying high energy to the first member at the start of bonding, and reducing the energy after a predetermined period of time has elapsed; and control means for controlling the displacement based on the output of the displacement detection means so as to cause the displacement to increase. 3) a vibrator, an ultrasonic oscillator that generates an electric signal for ultrasonic vibration of the vibrator, an ultrasonic vibration transmitter that transmits the ultrasonic vibration to a first member, and this ultrasonic vibration transmission a pressing means for pressing the first member against the second member with a body, and joining the first member to the second member by pressing the first member while applying the ultrasonic vibration. An ultrasonic bonding apparatus comprising: load detection means for detecting a load acting on the first member during the pressing; applying high energy to the first member at the start of bonding, and discharging the energy after a predetermined period of time has elapsed; An ultrasonic bonding apparatus comprising: control means for reducing the load in accordance with time based on the output of the load detection means.