JP2002217216A - Part bonding method and device thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a part to be very accurately bonded at a required position on a heat sink as a mounting object through a simple process and a structure. SOLUTION: A bonding device is equipped with an arranging mechanism 16 which arranges an LD chip 12 at a bonding position on the heat sink 14, first and second image pick-up means 18 and 22 which are disposed on the surfaces 12a and 12b of the LD chip 12, respectively, first and second lighting means 20 and 24 which are arranged so as to oppose the image pick-up means 18 and 22 with of the LD chip 12 between, an image processor 26 which enables the images picked up through the image pick-up means 18 and 22 to undergo a binarization process and calculates parallelism, and an inclination adjusting mechanism 28 which makes the angle adjustment of the heat sink 14 so as to enable the calculated parallelism to be within a specified tolerance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a component bonding method and apparatus for bonding a component to a predetermined position on a mounting object.

[0002]

2. Description of the Related Art Components such as semiconductor laser devices (hereinafter referred to as LDs) generate a large amount of internal heat during light emission.
In order to prevent self-destruction from occurring due to this heat, it is generally used in a state of being bonded by brazing on a heat sink having good thermal conductivity (object to be mounted).

At this time, in order to effectively release internal heat generated during light emission, which causes a reduction in the life of the LD, at the time of bonding, the tip of the LD chip and the heat sink are maintained at a relative positional accuracy of the order of μm, and at the same time, the position of the LD chip is reduced. It is necessary to bring the bonding surfaces of the heat sink into uniform contact with each other. Therefore, the allowable parallel accuracy (parallelism) between the bonding surfaces of the LD chip and the heat sink is ± 0.05.
゜ The following is very strict. In addition, the heat sink is required to have a parallelism on the heating surface opposite to the bonding surface, and the parallelism of the heat sink itself needs to be ± 0.05 ° or less. As a result, it has been pointed out that the manufacturing cost is considerably increased.

Therefore, for example, in Japanese Patent Laid-Open No. Hei 5-3223, in a paralleling mechanism for making the opposing planes of two members parallel to each other, both or one of the two members is connected via a spherical sliding portion. There is disclosed a technique of providing a means for supporting and guiding a high-pressure gas or vacuum to a spherical sliding portion, and a means for relatively pressing opposing flat surfaces of two members (hereinafter referred to as Conventional Technique 1).

Japanese Patent Laid-Open Publication No. Hei 6-140467 discloses that a plurality of capacitance sensors are attached to a pressure stage to determine the inclination of a bonding head with respect to the pressure stage. There is disclosed a technique for controlling the inclination correcting means so that the two are parallel (hereinafter, referred to as Conventional Technique 2).

Further, Japanese Patent Application Laid-Open No. H11-297765 discloses a method in which a plurality of pressure sensors are provided in a bonding tool, and a variation in pressure value is corrected by using a head surface adjusting unit, thereby obtaining a face surface of a semiconductor chip. A technique that uses a distance measuring device such as a laser displacement meter that detects the distance between the face surface of the semiconductor chip and the surface of the mounting substrate while ensuring the parallelism between the semiconductor chip and the surface of the mounting substrate is disclosed (hereinafter, referred to as the following). Conventional technology 3).

[0007]

However, according to the prior art 1, when the LD chip is to be brought into pressure contact with the object to be mounted, it is considerably large, for example, about 100 g.
Is required, and there is a problem that the LD chip is easily damaged. In addition, there is a problem that the structure becomes complicated and the equipment cost rises.

In the above-mentioned prior art 2, since at least three capacitance sensors are embedded in the pressure stage,
There is a problem that the equipment cost becomes considerably high.

Furthermore, in the above-mentioned prior art 3, it is necessary to scan a laser displacement meter or the like with high accuracy, and thus there is a problem that equipment costs rise and measurement takes time.

The present invention solves this kind of problem. In the present invention, a component is accurately arranged at a predetermined position on an object to be mounted, and the bonding surface between the component and the object is uniformly contacted. It is an object of the present invention to provide a method and apparatus for bonding components that can perform bonding.

[0011]

In the method and apparatus for bonding a component according to the present invention, after the component and the object to be mounted are relatively positioned with respect to the bonding position, the component and the object are positioned on one side of the component. The driven first imaging unit and the first illuminating unit disposed opposite to the first imaging unit with the component interposed therebetween are driven. That is, the first imaging unit and the first
The illuminating means and the illuminating means are arranged to face each other with the component interposed therebetween, and the illuminating light is emitted from the surface of the component opposite to the imaging surface. Is taken.

[0012] Thus, the first imaging means captures an image of the bright and dark portions of the gap formed between the bonding surfaces due to the transmitted light when the parallelism between the component and the mounting object occurs.
Here, when the first imaging means and the first illumination means are arranged on the same surface side with respect to the component, this occurs when the parallelism between the bonding surfaces is, for example, ± 0.05 ° or less. A gap of the order of several μm between the bonding surfaces cannot be detected.

On the other hand, according to the present invention, since the first image pickup means and the first illumination means are arranged to face each other, it is possible to reliably photograph light transmitted through a minute gap between the bonding surfaces. In particular, it is possible to effectively detect gaps on the order of several μm that occur with an inclination of ± 0.05 ° or less.

Next, the photographed image is subjected to a binarization process, and the parallelism between the bonding surfaces in a direction intersecting the optical axis direction of the first photographing means is detected.

Similarly, a second imaging means arranged on the other surface side intersecting one surface of the component, and a second illumination means arranged opposite to the second imaging means with the component interposed therebetween. , A gap between the component and the bonding surface of the mounting object is photographed. Then, the photographed image is subjected to a binarization process, and the parallelism between the bonding surfaces in a direction intersecting with the optical axis direction of the second photographing means is detected.

Then, the relative angular position between the component and the mounting object is adjusted according to each of the detected parallelisms, and the parallelism between the bonding surface of the component and the mounting object is adjusted within an allowable range. . Therefore, it is only necessary to use the first and second imaging means and the first and second illumination means, and no damage or the like of components is caused. Moreover, the equipment can be kept inexpensive and economical.

[0017] Further, there are provided component holding means capable of holding the component and moving up and down, and contact detection means for detecting that the component has come into contact with the object to be mounted, so that the component bonding operation can be performed automatically and efficiently. Will be able to perform.

Further, the first and second image pickup means include:
In addition to the CCD camera, the first and second illumination means include a light source that emits illumination light toward the CCD camera. As a result, the configuration is effectively simplified, and the gap between the bonding surface of the component and the mounting target can be detected with high accuracy and easily, and the bonding operation of the component and the mounting target can be accurately performed. Is done.

[0019]

FIG. 1 is a schematic perspective explanatory view of a component bonding apparatus 10 according to an embodiment of the present invention.
FIG. 2 is a side view of the bonding apparatus 10, and FIG. 3 is a front view of the bonding apparatus 10.

The bonding apparatus 10 includes a component LD
(Laser diode) An arrangement mechanism 16 for disposing the chip 12 and the heat sink 14 to be mounted relatively to the bonding position, and a first image pickup means disposed on one surface 12a side of the LD chip 12 18 and the L
A first illuminating unit 20 arranged opposite to the first imaging unit 18 with the D chip 12 interposed therebetween, and a second imaging unit arranged on the other surface 12b of the LD chip 12 which intersects the surface 12a 22 and a second illuminating means 2 disposed opposite to the second imaging means 22 with the LD chip 12 interposed therebetween.
4, the LD chip 12 and the heat sink 14
An image processing unit 26 for detecting the parallelism between the bonding surfaces 12c and 14c, and a tilt adjustment for adjusting the relative angular position of the LD chip 12 and the heat sink 14 so that the detected parallelism is within an allowable range. And a mechanism 28.

XY- constituting the bonding apparatus 10
stage 30 is provided with a movable table 32 that can move in the X-axis direction and the Y-axis direction via driving means such as a ball screw (not shown). The movable table 32 is rotatable about the Z axis. A rotary table 34, which is a θ table, is arranged.

On the rotary table 34, a first angle adjustment stage 36 for the chip longitudinal direction (arrow Y direction) and a second angle adjustment stage 38 for the chip width direction (arrow X direction), which constitute the tilt adjustment mechanism 28, are stacked. Placed. A support member 40 is disposed on the second angle adjustment stage 38, and a heater 44 is mounted on the support member 40 via a heat insulating layer 42. An abutment member 4 is provided on the upper end of the support member 40.
6 is fixed.

A holding plate 48 is provided on the end surface 14b of the heat sink 14 opposite to the reference end surface 14a, and a spring 50 is interposed between the holding plate 48 and the end surface 14b. The heater 44 is provided with a suction hole 52 communicating with a vacuum source (not shown) for holding the heat sink 14 by suction.

Component holding means 54 constituting the arrangement mechanism 16
Is provided with a frame 62 fixed to a column 60 and extending in the Z-axis direction.
Is fixed. A ball screw 66 connected to the output shaft of the motor 64 and extending in the Z-axis direction
And is screwed into a nut member (not shown) provided in the apparatus. While the pressing means 70 is fixed to the Z-axis movable table 68,
The holding member 72 is mounted on the pressing means 70. The holding member 72 has a hollow shape, and the inside thereof communicates with a negative pressure source (not shown). The pressing means 70 includes the LD chip 1
Contact detecting means (not shown) having a displacement or pressure detection sensor is provided to detect that the heat sink 2 contacts the heat sink 14.

An image pickup section 75 is mounted on the upper portion of the column 60 via a mount 74. The imaging unit 75 includes one or a plurality of CCD cameras 76 and an optical lens system 78. As shown in FIGS. 2 and 3, the CCD camera 76 is connected to the image processing unit 26, and the image processing unit 26 converts the image of the LD chip 12 and the heat sink 14 captured by the CCD camera 76 into an image. It has a function of taking in as a signal and calculating the amount of each position shift, and inputs the calculation result to the control unit 80.

The first and second imaging means 18 and 22 include first and second CCD cameras 82 and 84, and the first and second illumination means 22 and 24 include the first and second CCD cameras 82 and 84. And first and second light sources 86 and 88 for irradiating the illumination light toward. The first and second CCD cameras 82 and 84 are connected to the image processing unit 26, while the first and second light sources 86 and 88 are connected to the control unit 80.

The image processing unit 26 performs binarization processing on the image of the gap between the LD chip 12 and the bonding surfaces 12c of the heat sink 14,
c and 14c are detected, and the control unit 80
Has a function of driving the tilt adjustment mechanism 28 based on the calculation result from the image processing unit 26 to perform angle correction.
A monitor 90 is connected to the image processing unit 26.

The bonding apparatus 1 thus configured
The operation 0 is described below with reference to the flowchart shown in FIG. 4 in relation to the bonding method according to the present embodiment.

First, the heat sink 14 is arranged on the heater 44, and the suction holes 52 provided in the heater 44 are provided.
The heat sink 14 is suction-held on the heater 44 by performing suction from the heater 44. At this time, the reference end surface 14a of the heat sink 14 for positioning the LD chip 12 is positioned by contact with the abutting member 46, and the spring 50 is in contact with the end surface 14b of the heat sink 14.

On the other hand, in the component holding means 54, the holding member 7
The LD chip 12 is suction-held at the tip of the second 2 (step S1), and the XY-θ stage 30 is driven via the control unit 80. For this reason, the bonding position of the heat sink 14 is arranged on the optical axis of the imaging unit 75. Next, the Z-axis movable table 68 is lowered via the ball screw 66 under the action of the motor 64, and the LD chip 12 suction-held by the holding member 72 is lowered. When the contact detector (not shown) detects that the LD chip 12 has been placed with respect to the bonding position of the heat sink 14 (YES in step S2), the motor 64 is stopped via the control unit 80.

Therefore, the first illuminating means 20 comprises the first
The light source 86 is turned on, and the bonding surfaces 12c, 14c of the LD chip 12 and the heat sink 14 are photographed by the first CCD camera 82 constituting the first image pickup means 18 arranged to face the first light source 86 ( Step S
3).

The image photographed by the first image pickup means 18 is sent to the image processing section 26, and the monitor 90 displays, for example, the bonding surface 12c of the LD chip 12 and the bonding surface of the heat sink 14, as shown in FIG. A gap 92 between the gap and the space 14c is displayed. The image processing unit 26 performs a binarization process on the captured image, and calculates the parallelism of the LD chip 12 and the heat sink 14 in a chip width direction (a direction orthogonal to the optical axis direction of the first imaging unit 18). (Step S4).

Similarly, the LD chip 12 and the bonding surfaces 12c, 14c of the heat sink 14 in the chip longitudinal direction (second
An image is taken in a direction perpendicular to the optical axis direction of the image pickup means 22 (step S5). The image captured by the second imaging unit 22 is sent to the image processing unit 26, where the image is subjected to a binarization process, and the parallelism of the LD chip 12 and the heat sink 14 in the chip longitudinal direction is calculated (step S6).

After the parallelism in the chip width direction and the parallelism in the chip longitudinal direction are calculated as described above, the holding member 72 constituting the component holding means 54 is raised to a predetermined height position, and the LD chip 12 Is arranged at a predetermined height position with respect to the heat sink 14 (step S7). And
It is determined whether each of the calculated parallelisms is within the allowable range (step S8). If the parallelism is out of the allowable range, the process proceeds to step S9, where the tilt adjusting mechanism 28 is driven.

In the tilt adjusting mechanism 28, when the parallelism in the chip width direction is out of the allowable range, the first angle adjusting stage 36 is driven to adjust the stage tilt, while the parallelism in the chip longitudinal direction is adjusted. When the angle is out of the allowable range, the second angle adjustment stage 38 is driven to adjust the stage inclination.

Further, the above operation is performed until the parallelism in the chip width direction and the chip longitudinal direction is within the allowable range, thereby adjusting the parallelism between the LD chip 12 and the bonding surfaces 12c, 14c of the heat sink 14. Will be.

As described above, in the present embodiment, the one surface 12 of the LD chip 12 located at the bonding position
a and the other surface 12b, first and second imaging means 18 and 22 are disposed respectively, and the first and second imaging means 18 and 22 are opposed to the first and second imaging means 18 and 22, respectively. And second lighting means 20 and 24 are provided. For this reason, the first C
When photographing the bonding surface 12c of the LD chip 12 and the bonding surface 14c of the heat sink 14 via the CD camera 82, the first lighting means 20 is configured from the surface 12b opposite to the surface 12a of the LD chip 12. First
Illumination light is emitted via the light source 86.

As a result, the first CCD camera 82
Bonding surface 12c of D chip 12 and heat sink 1
4 can reliably photograph the bright and dark portions of the transmitted light that has passed through the gap 92 between the LD chip 12 and the bonding surface 14c. It is possible to easily detect the gap 92 on the order of several μm caused by the inclination. Therefore, the image taken by the first CCD camera 82 is binarized by the image processing unit 26, whereby the parallelism in the chip width direction between the LD chip 12 and the heat sink 14 can be obtained with high accuracy, and the bonding surface 12c of the LED 12 can be obtained. And the bonding surface 14c of the heat sink 14 can be bonded in a state where the bonding is uniformly and surely in contact with the entire surface.

Moreover, the first and second image pickup means 18, 2
2 and the first and second illuminating means 20 and 24 only need to be provided, the configuration is effectively simplified as compared with a conventional one using a capacitance sensor or the like, and the equipment cost does not rise so much. It has the advantage of being economical.

As described above, after the parallelism between the LD chip 12 and the heat sink 14 is adjusted to be within an allowable range, the L
The D chip 12 is raised integrally with the holding member 72 to a predetermined height position. Here, the imaging unit 75 is driven to drive the LD
The chip 12 and the heat sink 14 are imaged. The image signal obtained by the CCD camera 76 constituting the imaging unit 75 is sent to the image processing unit 26, where the image processing is performed.
The shift amount is calculated based on the relative position information between the LD chip 12 and the heat sink 14. This deviation amount is sent to the control unit 80, and the relative position correction between the LD chip 12 and the heat sink 14 is feedback-controlled in real time at regular time intervals.

For example, as shown in FIG.
When it is detected that the edge of No. 2 is displaced from the reference end surface 14a of the heat sink 14 by the correction amount Δθ (> reference value), the rotation table 34 provided on the XY-θ stage 30 corrects. Rotate by an angle corresponding to the amount △ θ,
The shift amount is corrected. Next, when the shift amount in the X-axis direction and the Y-axis direction is larger than the reference value, XY-
stage 30 is driven and feedback control is performed until the reference end surface 14a of the heat sink 14 matches the edge position of the LD chip 12.

After the amount of deviation between the LD chip 12 and the heat sink 14 falls within the allowable range, the heater 44 is heated to a predetermined temperature, in this embodiment, 120 ° C. Then, the motor 64 is driven to lower the Z-axis movable table 68, and the LD chip 1 sucked and held by the holding member 72.
2 abuts on the heat sink 14. Further, in a state where the LD chip 12 is pressed and held on the heat sink 14 with a constant load via the pressing means 70, the heater 44 is heated to a predetermined temperature, in this embodiment, 200 ° C. As a result, the brazing material previously provided on the upper surface of the heat sink 14 is melted, and after being heated for a predetermined time and cooled, the LD chip 12 is bonded onto the heat sink 14.

In this embodiment, the LD chip 12 is used as a component and the heat sink 14 is used as a mounting object. However, for example, a semiconductor chip may be used as a component and a substrate may be used as a mounting object. The effect of is obtained. Further, the heat sink 14 is connected to the XY-
The heat sink 14 is placed on the
Although it is configured to be movable in the axis, Y axis and θ axis directions,
The XY stage may be provided on the pressing means 70 for sucking and holding the LD chip 12, while the heat sink 14 may be mounted on the θ stage.

Furthermore, L with respect to the bonding position
When the D chip 12 and the heat sink 14 are arranged, the LD chip 12 is moved under the elevating action of the holding member 72, but the heat sink 14 may be moved. Further, although the contact detecting means is provided on the pressing means 70, it may be provided on the XY-θ stage 30 side, and the tilt adjusting mechanism 28 is provided on the XY-θ stage 30 side. However, it may be provided on the arrangement mechanism 16 side.

[0045]

According to the method and the apparatus for bonding a component according to the present invention, the component is connected to the component via first and second imaging means and first and second lighting means which are arranged to face each other with the component interposed therebetween. The gap between the bonding surfaces of the mounting object is photographed, and the photographed image is subjected to a binarization process to calculate the parallelism between the bonding surfaces. Therefore, the parallelism between the bonding surfaces is calculated with high accuracy by a simple process and configuration, and it is possible to bond the component to a predetermined position on the mounting object in a good state. Moreover, the equipment cost does not rise so that it is economical.

[Brief description of the drawings]

FIG. 1 is a schematic perspective explanatory view of a component bonding apparatus according to an embodiment of the present invention.

FIG. 2 is a side view of the bonding apparatus.

FIG. 3 is a front view of the bonding apparatus.

FIG. 4 is a flowchart illustrating a component bonding method according to an embodiment of the present invention.

FIG. 5 is an explanatory diagram of a photographing state by a first image pickup unit constituting the bonding apparatus.

FIG. 6 is an explanatory diagram of a photographing state by an image pickup unit included in the bonding apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Bonding apparatus 12 ... LD chip 12c, 14c ... Bonding surface 14 ... Heat sink 16 ... Arrangement mechanism 18, 22 ... Imaging means 20, 24 ... Illumination means 26 ... Image processing part 28 ... Tilt adjustment mechanism 30 ... XY-θ
Stages 36, 38 ... Angle adjustment stage 44 ... Heater 54 ... Component holding means 70 ... Pressurizing means 72 ... Holding member 75 ... Imaging unit 80 ... Control units 82, 84 ... CC
D camera 86, 88: Light source 90: Monitor

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kazuhiro Nishida 210 Nakanakanuma, Minamiashigara-shi, Kanagawa Prefecture Fuji Photo Film Co., Ltd. F-term (reference) 2F065 AA16 AA22 AA32 CC27 FF04 HH15 JJ05 JJ26 PP12 QQ04 5F047 FA72 FA73 FA83

Claims (4)

[Claims] 1. A component bonding method for bonding a component to a predetermined position on an object to be mounted, the method comprising: arranging the component and the object to be mounted relatively to a bonding position. The component and the object to be mounted via a first imaging unit disposed on one surface side of the component and a first illumination unit disposed opposite to the first imaging unit with the component interposed therebetween; Photographing a gap between the bonding surfaces, and performing a binarization process on the photographed image to calculate a parallelism between the bonding surfaces in a direction intersecting with an optical axis direction of the first imaging unit. And a second imaging means disposed on the other surface side of the component, which intersects the one surface, and a second lighting means disposed opposite to the second imaging device with the component interposed therebetween. Through which the component and the mounting object Photographing a gap between the bonding surfaces, and performing a binarization process on the photographed image to calculate a degree of parallelism between the bonding surfaces in a direction intersecting with an optical axis direction of the second imaging unit. And a step of adjusting a relative angular position between the component and the mounting object such that the calculated parallelisms fall within an allowable range. 2. A component bonding apparatus for bonding a component to a predetermined position on a mounting target object, wherein the positioning mechanism positions the component and the mounting target relative to a bonding position. A first imaging unit arranged on one surface side of the component; a first illumination unit arranged opposite the first imaging unit with the component interposed; and a first illumination unit arranged on the one surface side of the component. A second imaging unit disposed on the other surface side intersecting, a second illumination unit disposed opposite to the second imaging unit with the component interposed therebetween, and via the first and second imaging units A binarization process is performed on an image of the gap between the component and the bonding surface of the mounting object, which is taken, and the image is formed between the bonding surfaces in the direction intersecting the optical axis direction of the first and second imaging units. Processing to calculate parallelism of images If, as each parallelism the calculated falls within the allowable range, part of the bonding apparatus characterized by comprising: a tilt adjusting mechanism for adjusting the relative angular positions of the component and the mounting object. 3. The bonding apparatus according to claim 2, wherein the arrangement mechanism is configured to hold the component and move up and down, and a contact detection unit that detects that the component and the mounting target are in contact with each other. And a component bonding apparatus comprising: 4. A bonding apparatus according to claim 2, wherein said first and second imaging means include a CCD camera, and said first and second illumination means irradiate illumination light toward said CCD camera. A component bonding apparatus, comprising: