JPS59203675A - Generator for ultrasonic wave - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION C. Technical Field of the Invention The present invention relates to an ultrasonic generator, and particularly to an ultrasonic generator used in a semiconductor assembly device.

[Technical background of the invention]

2. Description of the Related Art In a semiconductor device manufacturing process, such as a bonding process, an ultrasonic bonding apparatus that uses ultrasonic energy is used.

Conventionally, in this bonding apparatus, the timing of ultrasonic oscillation output, ultrasonic power, and ultrasonic time were set by referring to data accumulated through past evaluation data, experience, and the like. First, trial bonding of an IC (integrated circuit) was performed.Observing the condition, the oscillation conditions were reset to make it favorable, and then the actual bonding was performed.

FIG. 1 shows the configuration of a conventional ultrasonic bonding apparatus. In the figure, I is an ultrasonic oscillation horn that generates ultrasonic waves. This ultrasonic oscillation horn I is attached to a vertical piece 3a of an L-shaped arm 3 supported by two shafts at a bent portion. A capillary 4 is attached to the tip of the ultrasonic oscillation horn I, and this capillary 4 applies pressure to a bonding wire (for example, an Al wire) 5 that is lowered through the inside of the capillary 4, and generates ultrasonic waves to send to the IC 6. Bonding is now being performed.

The tip of the horizontal piece 3b of the L-shaped arm 3 is connected to a drive motor 8 via a cam mechanism 7. Further, a pressurizing spring 10 is attached between the central part of the horizontal piece 3b and the fixing member 9, and the tensile force of the pressurizing spring 10 causes the capillary 4 to be attached to the bonding wire 5.
It is designed to put pressure on the When the drive motor 8 rotates and this rotational force is transmitted to the cam mechanism 7 via the belt 11, the L-shaped arm 3 reciprocates around the shaft 2 due to the intermittent movement of the cam mechanism 7. This causes the capillary 4 to move up and down in a reciprocating manner.

12 is a controller (microcomputer);
The controller I2 sends a bonding speed setting signal to the drive motor 8, and also sends a timing signal to the ultrasonic oscillator 13. In this ultrasonic oscillator 13, the operator adjusts the ultrasonic oscillation power and oscillation time using volumes 14 and 15, and the output thereof is sent to the ultrasonic oscillation horn 1.

That is, in this ultrasonic bonding apparatus, the ultrasonic oscillation power and oscillation time are set in advance using the volumes l4 and 15 of the ultrasonic oscillator 13, and when the bonding start button is pressed, the drive motor 8 is set in the controller 12. It rotates at the same speed. Therefore, the cam mechanism 7 operates and at the same time ultrasonic waves are generated from the ultrasonic oscillation horn I, so that bonding is performed in the capillary 4 portion. Further, the timing of this bonding is performed according to the timing set in the controller 12.

[Problems with background technology]

By the way, in the above bonding apparatus, external factors (mounting position of the capillary 4, tightening torque of the capillary 4, strength of the pressure spring 10, dirt on the surface of the IC 6,
Since good bonding cannot be achieved if the variation in the rotational speed of the drive motor 8 varies, it is necessary to change the conditions of the ultrasonic oscillation output (oscillation power, oscillation time, etc.) in accordance with the variation.

However, with conventional bonding equipment, it is not possible to change the ultrasonic oscillation output conditions in real time.
The conditions were changed after the operator noticed that the bonding condition was poor.

For this reason, defective products are manufactured until a defect is discovered, causing a decrease in yield. Furthermore, since it is not possible to monitor the ultrasonic vibration output signal, the setting of conditions relies on past experience, intuition, etc., and the setting values differ depending on the operator.

[Purpose of the invention]

This invention was made in view of the above circumstances, and its purpose is to make the ultrasonic oscillation force constant regardless of fluctuations in external factors,
An object of the present invention is to provide an ultrasonic generator capable of performing stable bonding and improving product yield.

[Summary of the invention]

This invention outputs an ultrasonic oscillation output signal from an ultrasonic oscillator to an ultrasonic oscillation horn, and simultaneously outputs an A/
After performing the D f conversion, a waveform analysis is performed by a microcomputer, and this microcomputer outputs a feedback signal to the ultrasonic oscillator to optimize various conditions such as oscillation power and oscillation time. The oscillation state of a sound wave oscillator is displayed on a CRT.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A case where an embodiment of the present invention is applied to a bonding apparatus will be described below with reference to the drawings. In FIG. 2, 2I is an ultrasonic oscillation horn, and this ultrasonic oscillation horn 2I is attached to a vertical piece 2'3a of an L-shaped arm 23 supported by a shaft 22 at a bent portion. A capillary 24 is attached to the tip of the ultrasonic oscillation horn 2I, and the capillary 24 applies pressure to the bonding wire 25 and generates ultrasonic waves to the IC 26.
Bonding is now performed. The pressing force of the capillary 24 is applied to the horizontal piece 2 of the L-shaped arm 23.
The tension is applied by the tension of a pressurizing spring 28 installed between the fixing member 3b and the fixing member 27.

The horizontal piece 23b of the L-shaped arm 23 is connected to a drive motor 30 via a cam mechanism 29.
When the rotational force is transmitted through the belt 31, the L-shaped arm 23 performs a reciprocating rotational movement due to the intermittent movement of the cam mechanism 29, thereby causing the capillary 24 to perform an up-and-down reciprocating movement.

32 is an ultrasonic oscillator, and this ultrasonic oscillator 32 sends an ultrasonic oscillation output signal A to the ultrasonic oscillation horn 21.
is now output. This ultrasonic oscillator 32
By adjusting the volume 3334,
Ultrasonic oscillation power and oscillation time can be changed. The output of the ultrasonic oscillator 32 is further A
After being converted into a digital signal by the /D converter 35, it is sent to a controller (microcomputer) 36. This controller 36 feeds back an ultrasonic power setting signal a, an ultrasonic time setting signal b, and an ultrasonic timing signal c to the ultrasonic oscillator 32, and also sends a bonding speed setting signal d to the drive motor 30. ing. That is, the controller 36 analyzes the waveform of the output signal from the ultrasonic oscillator 32 according to the program, and based on the results, sets the ultrasonic power setting signal a, the ultrasonic time signal b, the ultrasonic timing signal c, and the bonding speed setting signal d. by changing the output conditions of the ultrasonic oscillator 32 and the drive motor 30.
The ultrasonic oscillation output signal A from the ultrasonic oscillator 32 is thereby kept constant. Further, the ultrasonic oscillation output signal A from the ultrasonic oscillator 32 and the ultrasonic timing signal C from the controller 36 are input to the CRT 37, and the CR
At T37, the waveform of the ultrasonic oscillation output signal A is displayed.

That is, in this ultrasonic bonding apparatus, the ultrasonic oscillation power and oscillation time are set in advance using the volumes 33 and 34 of the ultrasonic oscillator 32, and when the bonding start button (not shown) is pressed, the drive motor 3
0 rotates at a speed set in the controller 36. The rotational force of the drive motor 30 is transmitted by the belt 31, and the cam mechanism 29 operates. As a result, the L-shaped arm 23 makes a reciprocating rotational movement about the shaft 22, and as a result, the capillary 24 makes an intermittently reciprocating movement up and down.

At the same time, the ultrasonic oscillator 32 outputs volumes 33 and 34.
An ultrasonic oscillation output signal A corresponding to the setting value is outputted at the timing set by the controller 36, thereby generating ultrasonic waves from the ultrasonic oscillation horn 21 and bonding to the lc 26.

However, in this bonding device, since the controller 36 analyzes the waveform of the ultrasonic oscillation output signal A and feeds it back to the ultrasonic oscillator 32, external factors such as the above-mentioned variation in the mounting position of the capillary 24 can be avoided. Even if there is a change, the super-sound oscillation output signal A can be brought into an appropriate state in real time in response to the change. Therefore, stable bonding can be performed, and the manufacturing yield is significantly improved compared to the conventional method. Also, the waveform (power, time, timing) of the ultrasonic oscillation output signal A is CR
Since it can be seen at T37, it becomes easy to set the output conditions of the super-sound wave oscillator 32 and adjust the bonding.

〔Effect of the invention〕

As described above, this invention has the following advantages. Since the ultrasonic oscillation output can be stabilized, good bonding can be achieved when applied to bonding equipment. Manufacturing yield can be improved.

[Brief explanation of drawings]

Figure 1 is a configuration diagram of a conventional ultrasonic bonding device, Figure 2
The figure is a configuration diagram of a bonding apparatus according to an embodiment of the present invention. 21... Ultrasonic oscillation horn, 24... Capillary,
25... Bonding wire, 28... Pressure spring, 29... Cam mechanism, 30... Drive motor, 3
2... Ultrasonic oscillator, 35... A/D converter, 36
···controller. 37...CRT.

Claims (2)

[Claims] (1) An ultrasonic oscillation horn that generates ultrasonic waves, an ultrasonic oscillator that outputs an ultrasonic oscillation output signal to this ultrasonic oscillation horn, and a waveform analysis of the output of this ultrasonic oscillator. An ultrasonic generator comprising: a controller that outputs a constant feedback signal. (2) The ultrasonic generator according to claim 1, wherein the waveform of the output of the ultrasonic oscillator is displayed on a CRT.