JP3297718B2 - Alignment camera, electronic component alignment method, and alignment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alignment camera and an alignment method used for mounting one electronic component on another electronic component, such as mounting a flip-chip type semiconductor element on a wiring board. , And an alignment device.

[0002]

2. Description of the Related Art At present, a flip-chip mounting structure has attracted attention as a mounting structure of a semiconductor device corresponding to a demand for small size and light weight. This mounting structure is a structure in which a flip-chip type semiconductor element having an electrode formed on the element surface is directly mounted face down on a wiring board, and both electrodes are electrically connected.

Conventionally, there is an alignment apparatus shown in FIG. 4 used for mounting a flip-chip type semiconductor element.

The alignment apparatus includes a holding section 50 for holding a flip-chip type semiconductor element A and a wiring board B with their electrode forming surfaces facing each other;
A distance extending / contracting portion 51 for extending / contracting an opposing distance between the semiconductor element A and the wiring board B held by the camera;
2, a camera moving unit 53 that moves the alignment camera 52 forward and backward between the retracted position outside the holding unit 50 and the inside of the holding unit 50, a display unit 54 that displays an image captured by the alignment camera 52, and a holding unit. And a position adjusting unit 55 for adjusting a relative positional relationship between the electrode forming surfaces of the semiconductor element A and the wiring substrate B held by the unit 50.

The holding section 50 includes a stage 56 on which the wiring board B is mounted, and a carrier 57 for holding the semiconductor element A. The alignment camera 52 includes first and second optical lenses 58A and 58B disposed opposite to each other, and first and second optical lenses 58A and 58B.
A prism 59 disposed between the second optical lenses 58A and 58B, and a third optical lens facing the prism 59 along a direction orthogonal to the direction in which the first and second optical lenses 58A and 58B face each other. And a CCD chip 61 facing the prism 59 with the third optical lens 60 interposed therebetween.

Next, a method of mounting the flip-chip type semiconductor element A using the alignment device will be described. First, the semiconductor element A and the wiring board B are mounted on the stage 56 and the carrier 57, respectively, with their electrode forming surfaces facing each other.

Then, the camera 52 for aligning the semiconductor device A and the wiring board B
Into the gap between Then, by adjusting the position of the carrier 57 by the space expansion / contraction part 51, the first,
The semiconductor element 51 and the wiring board 52 are located at positions corresponding to the focal lengths of the second optical lenses 58A and 58B.

In such a state, the images of the semiconductor element A and the wiring board B are collected on the prism 59 by the first and second optical lenses 58A and 58B, respectively. After being refracted to the side, an image is formed on the CCD chip 61 by the third optical lens 60.

Semiconductor device A imaged by CCD chip 61
The image signal of the wiring board B is sent from the CCD chip 61 to the display unit 54 and displayed.

The operator adjusts the relative position between the semiconductor element A and the wiring board B as follows while viewing the images of the semiconductor element A and the wiring board B displayed on the display unit 54. That is, the position adjusting unit 54 is driven via a manipulator (not shown) or the like to adjust the planar position of the carrier 57 (X direction, Y direction, θ angle: refer to FIG. 4 for these directions and angles). , Relative positioning of the semiconductor element A with respect to the wiring board B,
Perform alignment.

When the alignment operation is completed, the camera 53 moves the alignment camera 53 backward to the retracted position. Then, the carrier 57 is moved to the stage 56 side by the interval expansion / contraction portion 51, and
On the wiring board B. Then, in the previous process,
Since the alignment of the semiconductor element A and the wiring board B is adjusted, the electrode (not shown) of the semiconductor element A and the electrode (not shown) of the wiring board B abut. In this state, the holding operation of the semiconductor element A by the carrier 57 is stopped, and the carrier 57 is further retracted from the stage 56 by driving the space expansion / contraction portion 51. After the carrier 57 is retracted, the stage 56 on which the wiring board B and the semiconductor element A are mounted is moved to an operation position of a bonding tool (not shown), and a connection process between the semiconductor element A and the wiring board B is performed.

[0012]

The conventional alignment apparatus described above has the following problems.

The current connection pitch of the flip-chip type semiconductor element A is generally about 80 to 100 μm, but a narrow pitch is strongly required, and it is expected that a pitch of about 10 μm will be required in the future.

The alignment accuracy between the semiconductor element A and the wiring board B is determined by the mechanical accuracy of the position adjusting unit 55 and the facing distance J between the semiconductor element A and the wiring board B during alignment.
(See FIG. 4).

On the other hand, the first and second optical lenses 5
In a conventional alignment apparatus having an alignment camera 52 in which a prism 59 is disposed between 8A and 58B, the distance between the first and second optical lenses 58A and 58B, that is, the thickness H of the alignment apparatus (see FIG. 4) ) Is about 5
Therefore, the distance J between the semiconductor element A and the wiring board B at the time of alignment is about 90 mm or more.

As described above, when the semiconductor element A
In the conventional alignment device in which the facing distance J between the substrate and the wiring board B is required to be 90 mm or more, even if the position adjustment unit 55 having high mechanical accuracy is used, at present, only an alignment accuracy of ± 10 μm is obtained. This makes it impossible to realize mounting of the flip-chip type semiconductor element A having a connection pitch of 10 μm.

To solve such a problem, it is conceivable to improve the alignment accuracy by further improving the mechanical accuracy of the position adjusting unit 55. However, it is technically extremely difficult to further increase the mechanical accuracy of the position adjusting unit 55. Further, even if the mechanical accuracy could be improved, the configuration would have to be considerably expensive, and as a solution, I have to say that it is appropriate.

Further, even when considering the structure of the conventional alignment camera 52 itself, it cannot be said that it is difficult to increase the alignment accuracy. That is, the alignment camera 52 combines the image of the semiconductor element A and the image of the wiring board B with the prism 59 and forms an image on a single CCD chip 61. Therefore, in the alignment camera 52, the CCD
A plurality of pieces of image information such as image information of the semiconductor element A and image information of the wiring board B are input to each light receiving element constituting the chip 61.
1 cannot be sufficiently increased, and this is also a factor that makes it impossible to increase the alignment accuracy.

[0019]

According to the present invention, there is provided an alignment camera which is inserted between aligned members to be aligned with each other and collects images of the aligned members. It is characterized in that a plurality of image pickup devices are provided to collect the images, and these image pickup devices are arranged with their back surfaces facing each other. Further, the present invention is characterized in that an alignment method is configured by using the alignment camera. Further, the present invention is characterized in that an alignment apparatus is provided with the alignment camera.

[0020]

DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 of the present invention is directed to an alignment camera which is inserted and arranged between aligned members to be aligned with each other and takes an image of each aligned member. A plurality of imaging devices for individually capturing images of the alignment member are provided, and these imaging devices are arranged with their back surfaces facing each other to form an alignment camera. Has an action.

That is, the thickness between the imaging surfaces of both imaging devices can be reduced. Further, since the image of the member to be aligned can be individually captured by each imaging device, the image of the member to be aligned can be taken into the imaging device with high resolution.

According to a second aspect of the present invention, in the alignment camera according to the first aspect, a magnifying lens is disposed in front of an image pickup surface of each image pickup device. Has the effect of enlarging and forming an image on the imaging device.

According to a third aspect of the present invention, there is provided an electronic component alignment method for aligning a first electronic component and a second electronic component arranged with their electrode forming surfaces facing each other. An alignment camera is prepared by arranging the back surfaces of the imaging surfaces facing each other, and the alignment cameras are arranged such that the imaging surfaces of the imaging devices face the electrode forming surfaces of the first and second electronic components, respectively. In this state, the device is inserted between the first and second electronic components, an image of the electrode forming surface of the first and second electronic components is taken by each imaging device, and the images are displayed in a superimposed manner. ,
Recognizing the mutual position of the first and second electronic components on the basis of the displayed image, at least one of the electronic components so that the electrode of one of the electronic components matches the electrode of the other electronic component. The position is adjusted, thereby having the following operation. That is, since the facing distance between the first and second electronic components can be reduced, the alignment accuracy of the first and second electronic components is increased. Further, since the images of the first and second electronic components can be individually captured by the respective imaging devices, the resolution of the images of the first and second electronic components captured by the respective imaging devices can be increased.

According to a fourth aspect of the present invention, there is provided an electronic component alignment apparatus for aligning first and second electronic components arranged with their electrode forming surfaces facing each other. A gap is formed between the electrode forming surface and the holding portion for holding the electronic component with the electrode forming surfaces facing each other, and the distance between the first and second electronic components held by the holding portion. And an interval extending / contracting portion for extending / contracting between a position where the electrode forming surfaces are in contact with each other, an alignment camera in which a plurality of imaging devices are arranged with their back surfaces facing each other, and the alignment camera A camera moving unit that moves the camera forward and backward between a retracted position outside the holding unit and the gap after holding the camera in a state where the imaging surfaces of the imaging devices face each of the holding units,
A display unit that superimposes and displays the images of the electrode forming surfaces of the first and second electronic components photographed by the respective imaging devices; and an electrode forming surface of the first and second electronic components held by the holding unit. And a position adjustment unit for adjusting the relative position of the control unit, thereby having the following operation. That is, since the thickness between the imaging surfaces of both imaging devices of the alignment camera can be reduced, the first and second imaging devices can be reduced.
The opposing interval of the electronic components can be reduced. For this reason, the alignment accuracy of the first and second electronic components by the position adjustment unit is enhanced. Further, since the images of the first and second electronic components can be individually captured by the respective imaging devices, the resolution of the images of the first and second electronic components captured by the respective imaging devices can be increased.

According to a fifth aspect of the present invention, in the alignment apparatus according to the fourth aspect, the first electronic component is a flip-chip type semiconductor device and the second electronic component is a flip-chip type semiconductor device.
Is characterized by being a wiring board,
This has the following operation. That is, since the thickness between the imaging surfaces of the two imaging devices of the alignment camera can be reduced, the facing distance between the semiconductor element and the wiring substrate can be reduced. Therefore, the alignment accuracy between the semiconductor element and the wiring board by the position adjustment unit is improved. In addition, since the images of the semiconductor element and the wiring board can be individually captured by each imaging device, the resolution of the image of the semiconductor element or the wiring substrate captured by each imaging device increases.

An alignment apparatus according to an embodiment of the present invention will be described below with reference to FIG. This alignment device is an alignment device used when mounting a flip-chip type semiconductor element A on a wiring board B, and the flip-chip type semiconductor element A and the wiring board B are arranged in a state where their electrode forming surfaces face each other. Holding unit 1 for holding;
An interval expansion / contraction section 2 for expanding / contracting the opposing interval between the semiconductor element A and the wiring board B held by the holding section 1, and an alignment camera 3 which is a feature of the alignment apparatus 1.
And a camera moving unit 4 for moving the alignment camera 3 forward and backward between a retracted position outside the holding unit 1 and the inside of the holding unit 1.
A display unit 5 that displays an image captured by the alignment camera 3; and a position adjustment unit 6 that adjusts the relative positional relationship between the semiconductor element A and the electrode forming surface of the wiring board B held by the holding unit 1. And

The holding section 1 includes a stage 7 on which the wiring board B is mounted, and a carrier 8 for holding the semiconductor element A.

The alignment camera 3 includes a pair of CCDs.
It has chips 9A and 9B, a mounting board 10, and a cover 11. The CCD chips 9A and 9B have a flat plate shape with imaging surfaces 9Aa and 9Ba formed on the main surface. Have been.

Wiring patterns 10a and 10b are formed on the front and back surfaces of the mounting substrate 10, respectively. The external electrodes 9Ac and 9Bc of the CCD chips 9A and 9B are connected to the wiring patterns 10a and 9b by a connection structure such as wire bonding or TAB.
a, 10b. Wiring pattern 10a, 1
0b extends to the end of the mounting board 10, and the extending ends of the wiring patterns 10a and 10b
2A and 12B. CCD chips 9A, 9B
In this way, the external extraction electrodes 12A, 12B
Connected individually.

In FIG. 1, the external electrodes 9Ac and 9Bc are connected to the wiring patterns 10a and 10b by wire bonding using the wires 13.

The cover 11 connects the CCD chips 9A and 9B mounted on the mounting substrate 10 to the external lead electrodes 12A and 12A.
12B is pulled out and stored. Imaging surface 9A
a, a transparent plate 14 is provided on the portion of the cover 11 facing the 9Ba.
Is attached. The external lead electrodes 12A and 12B drawn from the cover 11 are connected to the display unit 5.

The display section 5 includes a signal processing circuit 5a for synthesizing the image signal sent from the CCD chip 9A and the image signal sent from the CCD chip 9B so as to be superimposed and displayed on one screen. Display unit main body 5b for displaying an image based on a composite image signal output from signal processing circuit 5a
And

When the alignment camera 3 is configured in this manner, the interval between the imaging surfaces 9Ab and 9Bb can be reduced due to its structure. Accordingly, the interval between the transparent plates 14 and 14, ie, the alignment camera 3 Overall thickness H
Can be made thinner. Specifically, the thickness H depends on the thickness of the CCD chips 9A and 9B and the mounting substrate 10, but is 2 m
m.

Next, an alignment method between the flip-chip type semiconductor element A and the wiring board B by the alignment apparatus will be described with reference to FIGS. In addition,
In each drawing of FIG. 2, the interval expanding / contracting unit 2, the camera moving unit 4, and the position adjusting unit 6 are not shown.

First, as shown in FIG. 2 (a), the carrier 8 is raised by the space expansion / contraction part 2, and a gap between the carrier 8 and the stage 7 is sufficient for the alignment camera 3 to move forward and backward. To form After the gaps are formed, the semiconductor element A and the wiring board B are mounted on the stage 7 and the carrier 8, respectively, with the electrode forming surfaces Aa and Ba facing each other.

After attaching the semiconductor element A and the wiring board B, as shown in FIG. 2B, the camera moving unit 4 moves the alignment camera 3 to the semiconductor element A and the wiring board B.
Into the gap between At this time, the CCD chip 9
The alignment camera 3 is moved with the imaging surfaces 9Aa and 9Ba of A and 9B (see FIG. 1) facing the semiconductor substrate A or the wiring substrate B.

Then, the position of the carrier 8 is adjusted by the interval expanding / contracting portion 2, so that the semiconductor element A and the wiring board B are located in the photographable areas of the CCD chips 9A and 9B. At this time, since the thickness of the alignment camera 3 is thin (about 2 mm) due to its configuration, the semiconductor device A and the wiring board B are positioned in the photographable areas of the CCD chips 9A and 9B. The facing distance (gap) J between the element A and the wiring board B can be reduced to about 6 to 7 mm.

When the alignment camera 3 is disposed in the holding section 1, the images of the semiconductor element A and the electrode forming surfaces Aa, Ba of the wiring board B are separately captured by the CCD chip 9 respectively.
Images are formed on A and 9B. As described above, the alignment camera 3 has a configuration in which a plurality of images are not captured by one CCD chip.
And the image of the wiring board B can be taken into the alignment camera 3 with the resolution maintained sufficiently high.

The image signals of the image of the semiconductor element A and the image of the wiring board B formed by the CCD chips 9A and 9B are
It is sent to the display unit 5 from the CD chips 9A and 9B. In the display unit 5, the image signal of the semiconductor element A and the image signal of the wiring board B are synthesized by the built-in signal processing circuit 5a so that they can be superimposed on one screen and displayed, and then synthesized. A composite image based on the image signal is displayed on the display unit main body 5b.

The operator looks at the images of the semiconductor element A and the wiring board B displayed on the display unit 5 while watching the semiconductor element A.
The relative position between the substrate and the wiring board B is adjusted as follows.
That is, the position adjusting unit 6 is driven via a manipulator (not shown) or the like, and the planar position of the carrier 8 (X direction,
Y direction, θ angle: These directions and angles are adjusted as shown in FIG. 1), whereby relative alignment of the semiconductor element A with respect to the wiring board B, that is, alignment is performed. At this time, since the facing distance J between the semiconductor element A and the wiring board B is as narrow as about 6 to 7 mm, an alignment accuracy of ± 2 to 3 μm can be obtained at the maximum, and a connection pitch of 10 μm can be obtained. Even the flip-chip type semiconductor element A can be accurately aligned.

When the alignment operation is completed, FIG.
As shown in FIG. 2C, the alignment camera 3 is retracted to the retreat position by the camera moving unit 4. Note that FIG.
In (c), the alignment camera 3 is not shown. Then, the carrier 8 is moved to the stage 7 side by the interval expansion / contraction portion 2 to make the semiconductor element A surface-attach to the wiring board B. Then, in the previous step, the alignment of the semiconductor element A and the wiring board B is adjusted, so that the electrode of the semiconductor element A (not shown) and the electrode of the wiring board B (not shown).
And abut.

In this state, as shown in FIG. 2D, the operation of holding the semiconductor element A by the carrier 8 is stopped, and furthermore, the carrier 8 is driven by driving the space expansion / contraction section 2 to move the carrier 8 to the stage 7.
Retreat (rise) from Thereby, the semiconductor element A is
It is placed on the wiring board B in an aligned state.

After the carrier 8 is retracted, FIG.
As shown in (5), the stage 7 on which the wiring board B and the semiconductor element A are mounted is moved to a position immediately below the bonding tool 15, and a connection process between the semiconductor element A and the wiring board B is performed. The connection operation by the bonding tool 15 is performed by pressurization by lowering the bonding tool 15 toward the semiconductor element A and the wiring board B or by heating by the bonding tool 15.

When the connection operation is completed, the bonding tool 15 is raised again to the retracted position. Thus, the operation of mounting the semiconductor element A on the wiring board B is completed.

In the above alignment apparatus, the cover 1
Although the alignment camera 3 having the transparent plate 14 adhered to 1 was used, the alignment camera 20 shown in FIG.
May be used. The alignment camera 20 is characterized in that a magnifying lens 16 is attached to the portion of the cover 11 facing the imaging surfaces 9Aa and 9Ba instead of the transparent plate 14.

If this alignment camera 20 is used, the alignment camera
Although the thickness H ′ of 0 is slightly thicker, the image can be enlarged and taken into each of the CCD chips 9A and 9B.
To that extent, it is possible to enlarge and display the image on the display unit 5, and accordingly, the alignment operation by the operator becomes easier, and the alignment accuracy is improved.

In the above-described embodiment, the present invention is implemented in the alignment apparatus used when mounting the flip-chip type semiconductor element A on the wiring board B. However, an electrode is formed on the surface. It goes without saying that the present invention can be implemented in alignment between other electronic components. Furthermore, it goes without saying that the present invention can be implemented in an alignment apparatus that performs an alignment operation on another member to be aligned that is not an electronic component.

[0048]

As described above, the present invention has the following effects.

Effect of Claim 1 The thickness between the imaging surfaces of both imaging devices can be reduced. For this reason, it is possible to reduce the interval between the members to be aligned into which the alignment camera is inserted, and to thereby increase the alignment accuracy of the members to be aligned.

Further, since the image of the member to be aligned can be taken into the image pickup device with high resolution, the alignment accuracy of the member to be aligned can be improved accordingly.

According to a second aspect of the present invention, an object to be imaged can be magnified and formed on an image pickup apparatus.
Further, the alignment accuracy has been improved.

According to the third and fourth aspects, since the facing distance between the first and second electronic components can be reduced, the alignment accuracy of the first and second electronic components is improved. In addition, since the images of the first and second electronic components can be individually captured by the respective imaging devices, the resolution of the images of the first and second electronic components captured by the respective imaging devices increases, As a result, the alignment accuracy has been further improved.

Further, such an improvement in the alignment accuracy is achieved by improving the alignment camera without increasing the mechanical accuracy of the position adjusting unit, which causes a great increase in cost. Never come.

According to a fifth aspect of the present invention, the distance between the semiconductor element and the wiring board at the time of alignment can be reduced, and the resolution of the image of the semiconductor element or the wiring board taken by each imaging device can be increased. did it. As a result, the alignment accuracy between the semiconductor element and the wiring board by the position adjustment unit could be improved without improving the mechanical accuracy of the position adjustment unit that would increase the cost. Therefore, it is possible to cope with the alignment of a flip-chip type semiconductor element having a pitch of about 10 μm, which will be required in the future, without increasing the cost.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an alignment apparatus according to an embodiment of the present invention.

FIG. 2 is a view showing each stage of an alignment operation between a semiconductor element and a wiring board using the alignment apparatus according to the embodiment;

FIG. 3 is a view showing a modification of the alignment camera.

FIG. 4 is a diagram showing a configuration of a conventional alignment apparatus.

[Explanation of symbols]

 3 Alignment Camera 9A, 9B CCD Chip 9Aa, 9Ba Imaging Surface 21 Magnifying Lens A Semiconductor Element B Wiring Board

──────────────────────────────────────────────────の Continued on the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04N 5/225 H04N 5/335 H01L 21/52 H01L 21/60 H01L 25/00 H01L 27/14 H05K 3 / 34 H05K 13/04

Claims (5)

(57) [Claims] 1. An alignment camera which is inserted between aligned members to be aligned with each other and captures an image of each aligned member, wherein the plurality of imaging cameras individually capture images of each aligned member. An alignment camera, comprising: a plurality of imaging devices, wherein the imaging devices are arranged with their back surfaces facing each other. 2. The alignment camera according to claim 1, wherein a magnifying lens is disposed in front of an imaging surface of each imaging device. 3. An electronic component alignment method for aligning a first electronic component and a second electronic component arranged with an electrode forming surface facing each other, wherein a plurality of image pickup devices face each other with their back surfaces facing each other. An alignment camera is prepared by arranging the first and second alignment cameras in a state where the imaging surfaces of the imaging devices face the respective electrode forming surfaces of the first and second electronic components. 2 between the two electronic components, images of the electrode forming surfaces of the first and second electronic components are taken by each imaging device, the images are superimposed and displayed, and based on the displayed images, Recognizing the mutual positions of the first and second electronic components, and adjusting the position of at least one of the electronic components so that the electrodes of one of the electronic components match the electrodes of the other electronic component. Electronic components Imento way. 4. An electronic component alignment device for aligning a first electronic component and a second electronic component arranged with their electrode forming surfaces facing each other, wherein the first and second electronic components are arranged on the electrode forming surface. And a holding portion for holding the first and second electronic components held by the holding portion at a position where a gap is formed between the electrode forming surfaces; An interval extending / contracting portion for extending / contracting between positions where the two come into contact with each other; an alignment camera in which a plurality of imaging devices are arranged with the back surfaces of the imaging surfaces thereof facing each other; A camera moving unit for moving the surface between the retracted position outside the holding unit and the gap after holding the surface in a state facing each of the holding units, and a first and second electronic component photographed by each imaging device. Electric A display unit that superimposes and displays an image of the formation surface; and a position adjustment unit that adjusts a relative position between the electrode formation surfaces of the first and second electronic components held by the holding unit. An alignment device characterized by the above-mentioned. 5. The alignment apparatus according to claim 4, wherein said first electronic component is a flip-chip type semiconductor element, and said second electronic component is a wiring board. apparatus.