JPH11238568A - Bonding equipment - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To detect whether or not foreign matter is attached to a lower end surface (bonding surface) of a bonding head. SOLUTION: A lower end surface of a bonding head 3 located at a bonding surface inspection position indicated by a two-dot chain line is picked up by a third camera 6, image recognition is performed, and an image signal corresponding to the recognized image is subjected to a third image processing. It is sent to the unit 11. The third image processing unit 11 performs image processing on the image signal and sends the image processing signal to the control unit 1. The control unit 1 determines whether or not a foreign matter is attached to the lower end surface of the bonding head 3 based on the image processing signal. When it is determined that the foreign matter is attached, the bonding operation is stopped, and an alarm is issued from the alarm unit 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bonding apparatus for bonding one electronic component to another electronic component.

[0002]

2. Description of the Related Art For example, when a semiconductor chip such as an LSI is mounted on a circuit board or a liquid crystal display panel, a bonding apparatus is used. In such a bonding apparatus, generally, a bonding head is disposed on a stage so as to be movable up and down, and is heated under pressure by a lowered bonding head, so that a semiconductor substrate is placed on a stage, for example, on a circuit board. The chip is to be bonded.

[0003]

By the way, in such a conventional bonding apparatus, if a foreign matter is attached to the lower end surface (bonding surface) of the bonding head, a defective product is generated. An inspection is performed to determine whether foreign matter has adhered to the lower end surface of the head. On the other hand, during the operation of the apparatus, foreign matter adhesion inspection cannot be performed. Therefore, the product after the bonding step is inspected, and when a defective product is generated, the apparatus is stopped to investigate the cause. However, when a defective product is generated due to the adhesion of foreign matter to the lower end surface of the bonding head, it takes a certain time from the time when the foreign material is attached to the time of product inspection. Was. In addition, there is a problem that it takes time to find out what is the cause of the defective product, and the operation rate is reduced. The problem of the present invention is that even when the device is in operation,
An object of the present invention is to detect whether or not foreign matter is attached to a bonding surface of a bonding head.

[0004]

SUMMARY OF THE INVENTION The present invention is directed to a bonding apparatus for bonding one electronic component to another electronic component by applying pressure and heating with a bonding head, wherein foreign matter adheres to the bonding surface of the bonding head. And a foreign matter adhesion detecting means for detecting whether or not the foreign matter is present. According to the present invention, the apparatus is provided with the foreign matter adhesion detecting means for detecting whether or not foreign matter has adhered to the bonding surface of the bonding head. Can be detected.

[0005]

FIG. 1 schematically shows a bonding apparatus according to a first embodiment of the present invention. This bonding apparatus includes a control unit 1 for controlling the entire apparatus, a stage 2 with a vacuum suction mechanism, a bonding head 3 with a vacuum suction mechanism, and first to third cameras 4 to 6 having a CCD type imaging device. Etc. are provided. The stage 2 is moved in the X and Y directions by the driving of the stage driving unit 7 controlled by the control unit 1. The stage 2 is moved in the X direction to at least a bondable position and a position detection position separated by a predetermined distance to the left from this position, as indicated by the solid line and the dashed line in FIG. It has become. Then, two first cameras 4 are arranged above the position detection position in this case. First camera 4
The image signal corresponding to the image captured at is sent to the first image processing unit 8. The first image processing unit 8 performs image processing on an image signal from the first camera 4, and sends the image processing signal to the control unit 1.

The bonding head 3 is driven by a head driving unit 9 controlled by the control unit 1 to drive X, Y,
It is designed to be moved in the Z and θ directions. Further, the bonding head 3 at least in the X direction, as shown by a solid line, an alternate long and short dash line and an alternate long and two short dashes line in FIG.
The position is moved to a bondable position, a position detection position separated by a predetermined distance to the right from this position, and a bonding surface inspection position further separated to the right by a predetermined distance from this position. And the second camera 5
Are arranged below the position detection position in this case. One third camera 6 is arranged below the bonding surface inspection position in this case. Image signals corresponding to the images captured by the second and third cameras 5 and 6 are sent to the second and third image processing units 10 and 11. The second and third image processing units 10 and 11 perform image processing on image signals from the second and third cameras 10 and 11, and transmit the image processing signals to the control unit 1. The control unit 1 is connected to a monitor television 12 and an alarm unit 13 that issues an alarm using an alarm lamp, an alarm buzzer, or the like.

Next, the semiconductor chip 14 and the circuit board 15 to be bonded in this case will be briefly described. The semiconductor chip 14 has a structure in which protruding electrodes (not shown) are provided on the lower surface in FIG. 1 of the chip body, and alignment marks (not shown) are provided at predetermined positions on both sides thereof. The circuit board 15 has a structure in which connection electrodes (not shown) are provided in a semiconductor chip mounting area on the upper surface of the substrate body in FIG. 1 and alignment marks (not shown) are provided at predetermined positions on both sides of the connection electrodes. Has become.

When bonding is performed by this bonding apparatus, first, the circuit board 15 supplied by various known methods is placed on the upper surface of the stage 2 located at a position detection position indicated by a dashed line in FIG. Positioning in the direction and adsorbing. Next, both alignment marks on the circuit board 15 are picked up by the two first cameras 4 and image recognition is performed, and an image signal corresponding to the recognized image is transmitted to the first image processing unit 8. The first image processing unit 8 performs image processing on the image signal and sends the image processing signal to the control unit 1. The control unit 1 calculates the amount of displacement of the circuit board 15 with respect to the reference position based on the image processing signal. Then, the control unit 1 controls the stage driving unit 7 based on the positional deviation amount, thereby performing the position correction of the circuit board 15 in the X and Y directions together with the stage 2. Thereafter, the stage 2 is moved to the right in FIG. 1 together with the circuit board 15 by a predetermined distance, and is positioned at a bondable position indicated by a solid line.

On the other hand, a semiconductor chip 14 supplied by various known methods is attracted to the lower surface of the bonding head 3 located at a position detection position indicated by a chain line in FIG. Next, both alignment marks (specific portions) of the semiconductor chip 14 are imaged by the two second cameras 5 and image recognition is performed, and an image signal corresponding to the recognized image is transmitted to the second image processing unit 10. . The second image processing unit 10 performs image processing on the image signal and sends the image processing signal to the control unit 1. The control unit 1 calculates the amount of displacement of the semiconductor chip 14 with respect to the reference position based on the image processing signal. Then, the control unit 1 controls the head driving unit 9 based on the positional deviation amount, and thereby corrects the position of the semiconductor chip 14 in the X, Y, and θ directions together with the bonding head 3. Thereafter, the bonding head 3 is moved to the left in FIG. 1 by a predetermined distance together with the semiconductor chip 14, and is positioned at a bondable position indicated by a solid line. In this state, the positions of the protruding electrodes of the semiconductor chip 14 and the connection electrodes of the circuit board 15 in the X, Y, and θ directions coincide with each other. Next, when the bonding head 3 is lowered and heated under pressure, the semiconductor chip 14 is attached to the circuit board 15.
Is bonded on the semiconductor chip mounting area.

Next, a case will be described in which the bonding apparatus detects whether or not foreign matter is attached to the lower end surface (bonding surface) of the bonding head 3. First,
The bonding head 3 is moved to a bonding surface inspection position indicated by a two-dot chain line in FIG. Then, the lower end surface of the bonding head 3 is picked up by one third camera 6 and image recognition is performed, and an image signal corresponding to the recognized image is transmitted to the third image processing unit 11. Third image processing unit 1
1 performs image processing on the image signal and sends the image processing signal to the control unit 1. The control unit 1 determines whether or not a foreign matter is attached to the lower end surface of the bonding head 3 based on the image processing signal. In other words, the control unit 1 compares the registered image signal corresponding to the lower end face of the normal bonding head 3 registered in advance with the image processing signal from the third image processing unit 11 by a pattern matching method or the like, and finds a difference. In this case, it is determined that the foreign matter is attached to the lower end surface of the bonding head 3. Then, the control unit 1 stops the bonding operation. In addition, an alarm is issued from the alarm unit 13 by light, sound, or the like.

In FIG. 1, the bonding surface inspection position indicated by the two-dot chain line is different from the position detection position indicated by the one-dot chain line, but may be the same position. In this case, two second cameras 5 are arranged on both sides below the position detection position indicated by the dashed line, and a third camera 6 is arranged at the center thereof. Then, before the semiconductor chip 14 is sucked onto the lower surface of the bonding head 3 located at the position detection position indicated by the dashed line, the lower end surface of the bonding head 3 is imaged by the third camera 6 to recognize the image.
Then, even if the apparatus is operating, it is possible to detect whether or not foreign matter is attached to the lower end surface of the bonding head 3. As a result, if foreign matter adheres to the lower end surface of the bonding head 3, this can be detected promptly, and the occurrence of defective products due to foreign matter adhesion to the lower end surface of the bonding head 3 can be reduced. In addition, the cause of the occurrence of defective products can be easily investigated, and the operation rate can be improved. Incidentally, the foreign substance adhesion test is performed by placing the semiconductor chip 1 on the lower surface of the bonding head 3.
4 may be performed each time before suction, or may be performed every predetermined number of times of bonding. Of course, it may be performed at the start of work.

When an alarm is issued from the alarm unit 13 by light, sound, or the like, the foreign matter adhering to the lower end surface of the bonding head 3 is removed manually or automatically. When removing automatically, for example, the bonding head 3 may be moved on a polishing stage and the lower end surface of the bonding head 3 may be polished to remove the adhered foreign matter. Further, by irradiating a laser beam or the like to the foreign matter attached to the lower end surface of the bonding head 3, the foreign matter (organic matter)
May be oxidized and removed.

In the above embodiment, the second camera 5
The case where the third camera 6 is disposed in addition to the above has been described, but the present invention is not limited to this. For example, one of the two second cameras 5 may also serve as the third camera 6. However, in this case, since the second camera 5 for recognizing the image of the alignment mark of the semiconductor chip 14 performs high-precision image recognition, the field of view is very narrow. Cannot be recognized at once. Therefore, the second camera 5 and the bonding head 3 located at the position detection position indicated by the one-dot chain line in FIG.
A magnifying lens (not shown) is removably arranged between the lower end surface of the lens and the lens. Then, in the case of the foreign substance adhesion inspection, the magnifying lens is positioned above the second camera 5, and the semiconductor chip 1
In the case of the position correction of 4, the magnifying lens is positioned at the standby position. In this way, the second camera 5 can also serve as the third camera 6. In the case shown in FIG. 1, the second and third cameras 5 and 6 may be provided on the stage 2. In addition, monitor TV 1
2, the images from the first to third cameras 4 to 6 and registered images may be displayed.

Next, FIG. 2A is a schematic front view of a main part of a bonding apparatus according to a second embodiment of the present invention, and FIG. 2B is a schematic plan view of a part thereof. In this bonding apparatus, a light emitting section 22 is provided on the right side of a bonding head 21 located at a bonding surface inspection position or a position detection position, and a light receiving section 23 is provided on the left side.
Is provided. The light emitting unit 22 includes the laser light generating unit 2
The laser light emitted from the laser beam 4 is converted into planar and parallel light (linear light) by the light projecting lens 25, and the parallel light is irradiated along the lower end surface of the bonding head 21 in parallel to the lower end surface. Has become. The light receiving unit 23 is a CCD
It has a line sensor 26 and receives a laser beam emitted from the light emitting unit 22.

In this bonding apparatus, when foreign matter adheres to the lower end surface of the bonding head 21, the laser light emitted from the light emitting section 22 is blocked by the foreign matter,
The amount of light received by the CCD line sensor 26 at a portion corresponding to the light-shielded portion becomes zero or decreases. Then, the light receiving section 23 binarizes this light receiving signal,
That is, when the amount of received light is normal, it is set to "1", and when it is abnormal, it is set to "0", and this binarized signal is sent to a control unit (not shown). Then, the control unit receives the signal from the light receiving unit 23.
It is determined whether or not there is an abnormal signal “0” in the quantified signal. If the abnormal signal is “0”, it is determined that foreign matter is attached to the lower end surface of the bonding head 21. As a result, the same effect as in the case of the first embodiment can be obtained. In addition, since the expensive third camera is not used, the apparatus can be made inexpensive.

FIG. 3 is a schematic front view of a main part of a bonding apparatus according to a third embodiment of the present invention. In this bonding apparatus, the light emitting section 32 is provided on the right side of the bonding head 31 located at the bonding surface inspection position or the position detection position, and the light receiving section 33 is provided on the left side. The light emitting section 32 converts the laser light emitted from the laser light generating section 34 into a polygon mirror 35.
The laser light converted to a surface light source is converted into a parallel light by a light projecting lens 36, and the parallel light is applied to the lower end surface of the bonding head 21 in parallel. . The light receiving section 33 has a CCD two-dimensional sensor 37 and receives the laser light emitted from the light emitting section 32.

In this bonding apparatus, the laser beam emitted from the light emitting section 32 is divided into three types. That is, the first is a laser beam interrupted by the lower right side surface of the bonding head 31, the second is a laser beam irradiated along the lower end surface of the bonding head 31, and the third is a lower end surface of the bonding head 31. It is a laser beam irradiated downward. Therefore, if foreign matter is attached to the lower end surface of the bonding head 31, the second
The laser light is blocked by the foreign matter, and the amount of light received by the CCD two-dimensional sensor 37 in the portion corresponding to the shielded portion becomes zero or decreases. Then, the light receiving unit 33 binarizes all the light receiving signals. In this case, the binarized signals corresponding to the first laser light are all “0”, the binarized signal corresponding to the second laser light is “1” including “0” in the middle, and the third All the binarized signals corresponding to the laser light are “1”. Then, this binarized signal is sent to a control unit (not shown). Then
The control unit outputs “0” to the binary signal from the light receiving unit 23 on the way.
It is determined whether or not there is a “1” including “0”. If there is a “1” including “0” in the middle, it is determined that the foreign matter is attached to the lower end surface of the bonding head 31. As a result, the same effect as in the case of the second embodiment can be obtained.

In the case of the second embodiment shown in FIG. 2, the light emitting section 22 is irradiated with laser light emitted from the light emitting section 22 along the lower end face of the bonding head 21 in parallel with the lower end face. And the CCD line sensor 26 of the light receiving section 23 must be arranged to receive the laser beam emitted from the light emitting section 22. High precision is required for the arrangement of the part 23. In contrast, FIG.
In the case of the third embodiment shown in FIG.
Since the second laser beam irradiated along the lower end surface of the first laser beam in parallel with the lower end surface is not specified, the light emitting unit 32
Also, high accuracy is not required for the arrangement of the light receiving unit 33.

FIG. 4 is a schematic front view of a main part of a bonding apparatus according to a fourth embodiment of the present invention. In this bonding apparatus, a stage 4 movable in X and Y directions is provided below a bonding head 41 located at a bonding surface inspection position or a position detection position.
2 is provided with a laser displacement meter 43 mounted on the top. The laser displacement meter 43 irradiates the laser light emitted from the laser light generator 44 with a spot on the lower end surface of the bonding head 41 via the light projecting lens 45, and reflects the reflected light with the CCD sensor 47 via the light receiving lens 46. Light is received, and an analog signal corresponding to the received light is amplified by an amplifier 48 and transmitted to a signal processing unit 49.

In this bonding apparatus, the stage 42
Is moved in the X and Y directions together with the laser displacement meter 43, and the laser light emitted from the laser light generating section 44 is projected by the light projecting lens 45 as shown by the solid arrow in FIG.
, And the reflected light is received by the CCD sensor 47 via the light receiving lens 46. When the foreign matter 50 indicated by a dotted line in FIG. 4 is attached to the lower end surface of the bonding head 21, the laser light is applied to the foreign matter 50 and reflected, as shown by the dotted arrow in FIG. 4. Then, the reflection position of the reflected light at this time is displaced, and C
The light receiving position by the CD sensor 47 is also displaced.
Then, an analog signal corresponding to the light receiving mode from the CCD sensor 47 is amplified by the amplifier 48 and
Sent to The signal processing unit 49 converts an analog signal into a digital signal, performs a predetermined operation based on the digital signal, and sends the operation result to a control unit (not shown). Then, based on the calculation result, the control unit, when the foreign matter 50 is attached to the lower end surface of the bonding head 21, causes the laser light emitted from the laser light generation unit 44 to be applied to the lower end surface of the bonding head 41. It is determined that the spot irradiation position has been displaced. As a result, the same effect as in the case of the second embodiment can be obtained. The stage 42 in this case may be shared by the stage 2 shown in FIG.

[0021]

As described above, according to the present invention, even if the apparatus is in operation, it is possible to detect whether or not foreign matter is attached to the bonding surface of the bonding head. If foreign matter adheres to the bonding surface of the bonding head, it can be detected quickly, and as a result, the occurrence of defective products due to foreign matter adhesion to the bonding surface of the bonding head can be reduced.
In addition, the cause of the occurrence of defective products can be easily investigated, and the operation rate can be improved.

[Brief description of the drawings]

FIG. 1 is a view schematically showing a bonding apparatus according to a first embodiment of the present invention.

FIG. 2A is a schematic front view of a main part of a bonding apparatus according to a second embodiment of the present invention, and FIG. 2B is a schematic plan view of a part thereof.

FIG. 3 is a schematic front view of a main part of a bonding apparatus according to a third embodiment of the present invention.

FIG. 4 is a schematic front view of a main part of a bonding apparatus according to a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Control part 2 Stage 3 Bonding head 4-6 Camera 13 Alarm part 14 Semiconductor chip 15 Circuit board

Claims (7)

[Claims] 1. A bonding apparatus for bonding one electronic component onto another electronic component by applying pressure and heating with a bonding head, wherein the foreign material detects whether a foreign material is attached to a bonding surface of the bonding head. A bonding apparatus comprising an adhesion detecting unit. 2. The bonding apparatus according to claim 1, wherein the foreign matter adhesion detecting means captures an image of a bonding surface of the bonding head and recognizes an image, and a bonding surface of the bonding head based on an image recognized by the camera. And a foreign matter adhesion determining means for determining whether foreign matter has adhered to the bonding apparatus. 3. The invention according to claim 2, wherein the camera is a camera that picks up an image of a specific portion of the one electronic component and recognizes the image, and a camera is provided between the camera and a bonding surface of the bonding head. A bonding device, wherein a magnifying lens is arranged so as to be insertable and removable. 4. The light emitting device according to claim 1, wherein said foreign matter adhesion detecting means emits light having a direction such as a laser beam in a linear or planar shape in parallel with a bonding surface of said bonding head. Means, light receiving means for receiving irradiation light from the light emitting means, and foreign matter adhesion determining means for determining whether foreign matter has adhered to the bonding surface of the bonding head based on a result of light reception by the light receiving means. A bonding apparatus comprising: 5. The invention according to claim 1, wherein the foreign matter adhesion detecting means irradiates a light having a direction such as a laser beam to a bonding surface of the bonding head so as to be reflected from the bonding surface. A light emitting unit; a light receiving unit for receiving light reflected from a bonding surface of the bonding head; and a foreign matter attachment for determining whether foreign matter is attached to the bonding surface of the bonding head based on a result of light reception by the light receiving unit. A bonding apparatus comprising: a determination unit. 6. The alarm device according to claim 1, wherein the foreign object adhesion detecting means detects a foreign object attached to the bonding surface of the bonding head and outputs a warning light or an alarm buzzer. And a means for performing at least one of alarming and stopping the bonding operation. 7. The invention according to claim 1, further comprising a foreign matter removing means for removing foreign matter when detecting that foreign matter has adhered to the bonding surface of the bonding head. A bonding apparatus characterized by the above-mentioned.