JP2008070158A - Amplitude measuring method and frequency measuring method of ultrasonic horn, measuring instrument using method, and ultrasonic bonding device using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a measuring method capable of performing easily amplitude measurement and frequency measurement of an ultrasonic horn, a measuring instrument using the method, and its ultrasonic bonding device. <P>SOLUTION: The measuring instrument includes a CCD camera having an enlargement magnification or an equal magnification for imaging the amplitude of the ultrasonic horn, a density detection part for detecting a density change of an image taken by the CCD camera, a distance measuring processing part for calculating the distance between a dense part and a pale part based on the density change detected by the density detection part, and an amplitude measuring part for measuring the amplitude of the ultrasonic horn from the distance between the dense part and the pale part calculated by the distance measuring processing part. The amplitude of the ultrasonic horn is taken by the CCD camera and then enlarged by image processing, and the amplitude and a resonance frequency of the ultrasonic horn are measured by utilizing an image in the amplitude state acquired at that time. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention provides an ultrasonic horn for use in an ultrasonic bonding method in which an electrode of a chip component such as an electronic component is pressed and heated against an electrode of a workpiece such as a substrate while applying ultrasonic vibration to the bonding portion. The present invention relates to a measuring method and measuring equipment for the amplitude and frequency of a pressure surface and an ultrasonic bonding apparatus using the measuring equipment.

  As a method for bonding a chip component to a substrate, an ultrasonic bonding method in which an electrode of the chip component is brought into contact with the electrode of the substrate and ultrasonic vibration is applied while pressing the chip component against the substrate electrode while the chip component is held by suction. It has been known.

  As a method for measuring the amplitude of such an ultrasonic horn, a method using a laser Doppler meter is known (for example, Patent Document 1).

JP-A-5-206224

  However, the conventional method has the following problems.

  Measurement of the amount of amplitude using a laser Doppler meter requires a large attachment of the measuring instrument to the joining device because the laser Doppler meter itself is large. Installation time is also required, so that the joining apparatus must be stopped for each measurement, and there is a problem that the amplitude cannot be measured without impairing product productivity. Further, the laser Doppler meter is expensive and cannot be installed for each joining apparatus. Therefore, in the production using ultrasonic waves, there is a problem that it is difficult to detect and manage the oscillation state of the ultrasonic horn.

  An object of the present invention is made in view of such circumstances, and is to provide a measurement method capable of easily measuring the amplitude and frequency of an ultrasonic horn, a measuring instrument using the method, and the ultrasonic wave thereof. It is to provide a joining apparatus.

According to the first aspect of the present invention, the amplitude of the ultrasonic horn is picked up by a CCD camera having an enlargement magnification or enlarged by image processing after being picked up by a CCD camera having an equal magnification. A method for measuring the amplitude and resonance frequency of an ultrasonic horn by using the image of
Detecting a change in shading of the image in the amplitude state by image processing;
Measuring the distance between the dark and light portions of the image in the amplitude state by automatic processing;
Measuring the amplitude of an ultrasonic horn from the measured data;
This is a method for measuring the amplitude of an ultrasonic horn comprising:

  A second aspect of the invention is a method for measuring the resonance frequency of an ultrasonic horn according to the first aspect of the invention, which includes the step of extracting only the dark portion of the image in the amplitude state by automatic processing.

  A third aspect of the invention is a method for measuring the amplitude of an ultrasonic horn according to the first aspect of the invention, which includes the step of manually determining a change in shading of the image in the amplitude state.

  A fourth aspect of the invention is a method for measuring the amplitude of an ultrasonic horn according to the third aspect of the invention, comprising the step of manually emphasizing a change in shading of the image in the amplitude state.

  According to a fifth aspect of the present invention, in the third aspect of the invention, the amplitude of the ultrasonic horn is measured, including a step of displaying a graph showing a change in shading on a display means based on the image of the amplitude state. Is the method.

  The invention according to claim 6 is the invention according to claim 1, in which the structure subjected to the dark portion processing in the same color as the ultrasonic horn is fixedly arranged in the vicinity of the ultrasonic horn, and the light portion of the image in the amplitude state is displayed. A method for measuring the amplitude of an ultrasonic horn including an emphasizing step.

The invention described in claim 7
A CCD camera with an enlargement magnification or equal magnification for imaging the amplitude of an ultrasonic horn;
A light and shade detecting unit for detecting a change in light and shade of an image captured by the CCD camera;
A distance measuring unit that calculates the distance between the dark part and the light part based on the change in light and shade detected by the light and shade detecting part,
An amplitude measurement unit for measuring the amplitude of the ultrasonic horn from the distance between the dark part and the light part calculated by the distance measurement unit;
Is an amplitude measuring instrument of an ultrasonic horn equipped with

The invention according to claim 8 is the invention according to claim 7,
The ultrasonic horn frequency measurement device includes a resonance frequency measurement unit that extracts a dark portion detected by the light and shade detection unit and measures a resonance frequency of the ultrasonic horn.

  The invention according to claim 9 is an ultrasonic bonding apparatus on which the invention according to claim 7 or claim 8 is mounted.

  According to the first aspect of the present invention, since the distance between the dark part and the light part can be measured by automatic processing and the amplitude of the ultrasonic horn can be measured, it is possible to connect a large measuring device such as a laser Doppler meter to the joining device. No need for mounting, and amplitude measurement can be performed easily.

  According to the invention described in claim 2, since only the dark portion is extracted by automatic processing and the resonance frequency of the ultrasonic horn can be measured, it is not necessary to attach a large measuring device such as a laser Doppler meter to the joining device. Thus, the resonance frequency can be easily measured.

  According to the third aspect of the present invention, since the change in shading of the image in the amplitude state is determined by manual operation, the amplitude can be measured even when the image data is unclear.

  According to the fourth aspect of the present invention, since the change in shading of the image in the amplitude state is emphasized by manual operation, the amplitude measurement can be performed even for image data in which the shading is ambiguous.

  According to the fifth aspect of the present invention, since the graph showing the change in shading is displayed on the display means based on the image in the amplitude state, manual operation can be easily performed.

  According to the sixth aspect of the present invention, the structure subjected to the dark color processing in the same color as the ultrasonic horn is fixedly arranged in the vicinity of the ultrasonic horn to emphasize the light portion of the image in the amplitude state. The influence of the background etc. can be reduced.

  According to the seventh aspect of the present invention, a CCD camera having an enlargement magnification or an equal magnification for imaging the amplitude of the ultrasonic horn, and a density detection unit for detecting a change in density of an image captured by the CCD camera, Because it has a distance measurement unit that calculates the distance between the dark part and the light part based on the change in light and shade, and an amplitude measurement part that measures the amplitude of the ultrasonic horn from the distance between the dark part and the light part The amplitude of the ultrasonic horn can be easily measured without using a laser Doppler meter.

  According to the eighth aspect of the present invention, since the resonance frequency measuring unit is further provided, the resonance frequency of the ultrasonic horn can be easily measured.

  According to the invention described in claim 9, since the state of the amplitude and the resonance frequency of the ultrasonic horn can be recorded for each joint, the oscillation abnormality of the ultrasonic horn and the assembly quality at the time of recombination of the ultrasonic horn are determined. Can be used for judgment. And the detection management of the oscillation state of an ultrasonic horn can be performed, and joining quality can be improved.

  Embodiments of the present invention will be described below with reference to the drawings. In the embodiment, a case where an electronic component with a bump is mounted on a substrate as a chip component will be described as an example. In addition, as the chip component, for example, all forms on the side to be bonded to the substrate are shown regardless of the type and size of an IC chip, a semiconductor chip, an optical element, a surface mount component, a wafer, and the like.

  Moreover, as a board | substrate, all the forms of the side joined to chip components, such as a resin substrate, a glass substrate, a film substrate, are shown, for example.

  FIG. 1 is a front view of an ultrasonic bonding apparatus according to an embodiment.

  As shown in FIG. 1, the ultrasonic bonding apparatus 100 according to the embodiment is supported by a movable table 3 having a substrate holder 2 that holds the substrate 1 by suction, and a vertical wall 5 erected at the rear portion of the base 4. A crimping mechanism 9 that includes a crimping head 8 that is attached via the frame 6 and that is mounted (bonded) to the substrate 1 by sucking and holding the chip component 7 at the tip, and the substrate 1 and the crimping head 8 that are held by the substrate holder 2. A camera 10 for recognizing the position of the chip component 7 held by suction, a CCD camera 31, the movable table 3, the pressure-bonding head 8, the pressure-bonding mechanism 9, and the main control unit 11 that controls the drive of the camera 10. Is provided.

  The movable table 3 is configured to be movable in two horizontal (X, Y) directions in the left and right and front and rear directions in the figure. Further, the substrate holder 2 provided in the movable table 3 has a suction hole 21 formed in the surface portion on which the substrate 1 is placed, and the suction hole 21 is connected to a vacuum pump (not shown) via a pipe. . In the embodiment, the holding of the substrate 1 in the substrate holder 2 is an adsorption type. However, the holding method is not limited to the adsorption type. Any holding structure such as magnetic adsorption can be used.

  The crimping mechanism 9 includes a cylinder 12 fixed to the support frame 6, a head main body 14 connected to a rod 13 directed vertically downward of the cylinder 12, and a crimping head 8 provided at a lower end of the head main body 14. It is composed of That is, the pressure bonding head 8 is configured to move up and down in conjunction with the expansion and contraction operation of the cylinder 12.

  The camera 10 is movable in two horizontal axes (X, Y) and up and down (Z). In addition, a lens barrel 23 is provided that moves forward and backward toward the crimping head 8 side. Further, the camera 10 is moved forward in the X-axis direction, and is positioned between the chip component 7 held by the suction member of the horn 35 and the substrate 1. In this state, the positions of the chip component 7 and the substrate 1 are recognized and observed, and the observation result is transmitted to the main control unit 11. As the position of both members and the means for observing, all forms that can recognize the positions of the substrate 1 and the chip component 7 can be applied in addition to the camera, for example, regardless of the type of infrared camera, sensor, or the like.

  The main control unit 11 selects a bonding condition according to the types of the substrate 1 and the chip component 7 to be bonded set and input from the operation unit 24 from a pattern table (not shown), and transmits the selected pattern to the amplitude control unit 25. . The main control unit 11 also comprehensively controls driving of the movable table 3, the cylinder 12, the camera 10, and the like based on information set and input from the operation unit 24. Further, image data picked up by the CCD camera 31 is input to the image processing unit 37, and data of the amplitude and resonance frequency of the horn 35 processed by the image processing unit 37 is transmitted to the main control unit 11. ing. A monitor 38 for confirming image data is connected to the image processing unit 37. The image processing unit 37 includes a density detecting unit 39 that detects the density of image data captured by the CCD camera 31, a distance measuring unit 40 that calculates the distance between the dark part and the light part based on the change in density, An amplitude measuring unit 41 that measures the amplitude of the ultrasonic horn from the distance between the dark portion and the light portion, and a resonance frequency measuring portion that extracts the dark portion detected by the light and shade detecting portion 39 and measures the resonance frequency of the ultrasonic horn. 42.

  FIG. 2 shows the relationship between the configuration of the ultrasonic horn unit 30 mounted on the crimping head 8 and the mounting position of the CCD camera 31 in the present invention.

  The ultrasonic horn unit 30 is designed to have the same natural frequency as that of the vibrator 32 after the ultrasonic vibration oscillated from the vibrator 32 is rectified by the intermediate booster 33 and increased or decreased by the solid booster 34. Transmission to the horn 35 causes resonance vibration.

  The horn 35 is attached to the crimping head 8 via a holder mounting base 36 with solid boosters 34 provided at both ends holding the both ends.

  In the present embodiment, the CCD camera 31 is disposed on the front side in the Y direction of the ultrasonic bonding apparatus 100 so that one end of the horn 35 can be enlarged or photographed at the same magnification. An observation point X of the horn 35 by the CCD camera 31 is shown in FIG.

  FIG. 3 is a basic conceptual diagram of amplitude measurement in the present invention.

  When the vibrator 32 does not oscillate and the horn 35 does not resonate, the horn 35 stops at the reference position A.

  In a state where the vibrator 32 oscillates and the horn 35 is resonantly oscillated, the horn 35 moves in the positive direction of the X axis, reaches the amplitude end B, and moves in the X direction through the reference position A. Is repeated, reaching the amplitude end C, and moving to the reference position A again. At this time, when the CCD camera 31 having an enlargement magnification is brought close to the observation point X shown in FIG. 2 and the image is taken in, the reference point A that passes twice in one cycle is dark, and the amplitude end B in the X axis + direction. And, it appears thin at the amplitude end C in the negative direction. In this way, a change in the image in the amplitude state (change in light and shade) is detected by the light and shade detection unit 39 of the image processing unit 37.

  The CCD camera 31 does not need to have a special function, and a generally available shutter speed of 1/1000 or 1/2000 is sufficient (if the shutter speed is 1/1000, the shutter can be opened and closed once. 20 to 60 amplitude images can be captured).

  In the present invention, the amount of amplitude of the horn 35 is measured using this shading.

  FIG. 4 is a graph in which the change in shading is processed by the shading detection unit 39 based on the image captured by the basic concept of FIG. The horizontal axis indicates the amplitude, and the vertical axis indicates the intensity.

  At the reference position A, it is darkest, and at the amplitude end B in the X axis + direction and at the amplitude end C in the-direction, it is lighter. The shading is graphed by image processing, the half amplitude amount at the amplitude ends B and C is calculated from the reference position A, and the amplitude amount of the horn 35 itself is calculated by the sum of the plus direction half amplitude amount and the minus direction half amplitude amount. calculate. Thus, the distance measurement unit 40 measures the distance between the dark portion and the light portion of the image in the amplitude state.

  The determination of the light portion takes into account the background error during image processing and the image capturing error of the CCD camera 31 by providing a threshold that can be set individually.

  In addition, the measurement of the amplitude amount is preferably calculated by automatic calculation. However, the amplitude is also displayed by displaying the captured image itself on the monitor 38 and designating a light portion using a mouse or the like by visual observation of the operator. The amount can be calculated. It is also possible to display the graph of FIG. 4 on the monitor 38 and perform the same operation visually by the operator to calculate the amplitude amount.

  FIG. 5 is a diagram illustrating an example of a manual measurement method. FIG. 5 (a) is a graph showing the change in shading on the monitor 38 by the processing of the shading detection unit 39. The operator digitizes the curve on the graph with a mouse or the like, thereby determining the position, and the digitized position. It shows that amplitude measurement is performed based on this. In this way, the change in the shade of the image in the amplitude state is determined by manual operation, and the amplitude is measured.

  In FIG. 5B, the change in shading is emphasized by the shading detection unit 39, and the operator digitizes the image with a mouse or the like to determine the position, and based on the digitized position. It shows that amplitude measurement is performed.

  Further, in manually determining the light part, it is also effective in carrying out the present invention that the light part is made clear by fixing and arranging a structure that is processed in the same manner as the horn 35 in the vicinity of the end of the horn 35. Means. This method of manually emphasizing the change in shading also has the effect of clarifying the shading change in the shading detector 39 and improving the processing speed.

  6 automatically calculates the reference position A based on the information obtained by the measurement method shown in FIGS. 3 to 5, and the number of dark peaks at the reference position A within a preset set time. It is a conceptual diagram at the time of calculating | requiring the resonant frequency based on this.

  Within the set time, the number of dark portions indicating the reference position A is counted, and the resonance frequency is automatically calculated based on the number. In the present embodiment, there are N (four) dark portions in the set time (T), and the frequency is f = (N / 2) / T Hz. In this way, the resonance frequency can be measured by extracting only the dark portion of the image in the amplitude state by automatic processing.

  As described above, a CCD camera having an enlargement magnification or an equal magnification for imaging the amplitude of an ultrasonic horn, a light / dark detection unit for detecting a light / dark change in an image captured by the CCD camera, and a light / dark change The laser Doppler has a distance measurement processing unit that calculates the distance between the dark part and the light part and an amplitude measurement part that measures the amplitude of the ultrasonic horn from the distance between the dark part and the light part. Without using a meter, the amplitude of the ultrasonic horn can be easily measured.

It is a front view which shows the whole ultrasonic bonding apparatus which concerns on embodiment. It is a front view which shows the principal part structure of a horn. It is a figure explaining the image | video at the time of resonance of a horn. It is a figure explaining the amplitude amount of a horn. It is a figure explaining the measuring method of the amount of amplitudes manually. It is a figure explaining the measuring method of a resonant frequency.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Board | substrate 2 Board | substrate holder 3 Movable table 4 Base 5 Vertical wall 6 Support frame 7 Chip component 8 Crimp head 9 Crimp mechanism 10 Camera 11 Main control part 12 Cylinder 13 Rod 14 Head main body 21 Suction hole 23 Lens barrel 24 Operation part 25 Amplitude Control unit 30 Ultrasonic horn unit 31 CCD camera 32 Vibrator 33 Booster 34 Solid booster 35 Horn 36 Base 37 Image processing unit 38 Monitor 39 Shading detection unit 40 Distance measurement unit 41 Amplitude measurement unit 42 Resonance frequency measurement unit 100 Ultrasonic bonding device X observation point

Claims (9)

The ultrasonic horn is picked up by a CCD camera having an enlargement magnification, or is picked up by a CCD camera having an equal magnification and then enlarged by image processing, and an ultrasonic wave is obtained by using an image in the amplitude state obtained at that time. A method for measuring the amplitude and resonant frequency of a horn, comprising:
Detecting a change in shading of the image in the amplitude state by image processing;
Measuring the distance between the dark and light portions of the image in the amplitude state by automatic processing;
Measuring the amplitude of an ultrasonic horn from the measured data;
A method for measuring the amplitude of an ultrasonic horn comprising: 2. The method according to claim 1, wherein the resonance frequency of the ultrasonic horn includes a step of extracting only a dark portion of the image in the amplitude state by automatic processing. The method of measuring the amplitude of an ultrasonic horn according to claim 1, comprising a step of determining a change in shading of the image in the amplitude state by a manual operation. 4. The method of measuring an amplitude of an ultrasonic horn according to claim 3, further comprising the step of manually highlighting a change in shading of the image in the amplitude state. 4. The method of measuring an amplitude of an ultrasonic horn according to claim 3, further comprising a step of causing a display means to display a graph showing a change in shading based on the amplitude state image. In the invention according to claim 1, there is provided an ultrasonic horn including a step of emphasizing a light portion of an image in the amplitude state by fixing and arranging a structure that has been darkly processed in the same color as the ultrasonic horn in the vicinity of the ultrasonic horn. A method of measuring amplitude. A CCD camera with an enlargement magnification or equal magnification for imaging the amplitude of an ultrasonic horn;
A light and shade detecting unit for detecting a change in light and shade of an image captured by the CCD camera;
A distance measuring unit that calculates the distance between the dark part and the light part based on the change in light and shade detected by the light and shade detecting part,
An amplitude measurement unit for measuring the amplitude of the ultrasonic horn from the distance between the dark part and the light part calculated by the distance measurement unit;
Ultrasonic horn amplitude measuring instrument equipped with. In the invention of claim 7,
An ultrasonic horn frequency measuring device including a resonance frequency measuring unit that extracts a dark portion detected by the light and shade detecting unit and measures a resonance frequency of the ultrasonic horn. An ultrasonic bonding apparatus on which the invention according to claim 7 or 8 is mounted.

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