JPH07135228A - Die-bonding device for mounting electronic part on board - Google Patents

Abstract

PURPOSE:To bond electronic elements on a substrate efficiently and reliably. CONSTITUTION:Suction collets 10 and 11 which hold electronic parts and transfer them to mounting spots on a substrate 7. Especially, these suction collets have such a feature that the collects are composed of a first suction collect 10 for the surface 7a of the board 7 and a second suction collect 11 for the surface 7b of the substrate 7. Therefore, electronic parts can be mounted on both the front 7a and rear 7b of the substrate 7 at a time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a die bonding apparatus for mounting electronic components such as semiconductor chips, chip capacitors and chip resistors on a substrate.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
For example, JP-A-4-196545 and JP-A-4-15.
In the substrate disclosed in Japanese Patent No. 5856, electronic components are mounted on both front and back surfaces to achieve high integration of electronic components.

By the way, as a conventional die bonding apparatus, there is one shown in, for example, Japanese Patent Laid-Open No. 190247/1993. In this device, semiconductor chips can be mounted one by one on a lead frame or a die stage of a package in a collet of a bonding arm that is movable in three dimensions. However, in the same device, the semiconductor chip can only be mounted on the die stage only from above.

When electronic components are mounted on both front and back surfaces of a substrate by using such a die bonding apparatus, for example, as shown in FIG. 7 of JP-A-4-196545,
First, after mounting the electronic component on the front surface of the substrate, the substrate must be turned upside down to mount the electronic component on the back surface of the substrate. Therefore, mounting time on the front surface of the substrate, inversion work time of the substrate, and mounting time on the back surface of the substrate are required,
There was a problem in shortening the bonding work time. Further, when the substrate is inverted by hand, the substrate may be soiled or damaged, which may adversely affect the quality.

An object of the present invention is to provide a die bonding apparatus which improves the collet to shorten the time for mounting electronic components on both front and back surfaces of a substrate and to improve the reliability of quality.

[0006]

The present invention relates to a die bonding apparatus for mounting electronic components on a substrate, which is equipped with a collet for holding the electronic components and transporting them to the mounting location on the substrate.

In particular, this collet has a great feature not heretofore available in that it has a first collet for the front surface of the substrate and a second collet for the back surface of the substrate.

[0008]

Therefore, by utilizing the first and second collets, electronic components can be simultaneously mounted on both front and back surfaces of the substrate.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the die bonding apparatus according to the present invention will be described below with reference to the schematic drawings.

As shown in FIG. 2, a substrate supply side stocker 2 and a substrate discharge side stocker 3 are provided on the frame 1, and a substrate transfer conveyor 4 is provided between the stockers 2 and 3.
Is provided. In the conveyor 4, a pair of timing belts 5 are bridged between the stockers 2 and 3, and a plurality of gripping claws 6 are attached to the belts 5 at equal intervals to face each other. Then, the substrate 7 in the substrate supply side stocker 2 is the timing belt 5
The electronic parts mounting position P is sandwiched by the gripping claws 6
And is stopped at the same position P. Further, after mounting, the substrate 7 is sent to the substrate discharge side stocker 3 and separated from the gripping claws 6 of both timing belts 5.

As shown in FIG. 1, at the electronic component mounting position P on the substrate transfer conveyor 4, bonding arms 8 and 9 are provided in both upper and lower spaces thereof.
Adsorption collets 10 and 11 are attached to the tips of the upper and lower bonding arms 8 and 9 so as to face the electronic component mounting position P, respectively. The base ends of the upper and lower bonding arms 8 and 9 are supported by a three-dimensional drive mechanism 12 in the frame 1, respectively. The upper and lower suction collets 10, 11 are movable in the front-rear direction, the left-right direction, and the up-down direction.

Adjacent to the upper and lower bonding arms 8 and 9, support arms 13 and 14 are provided above and below the electronic component mounting position P, respectively. Pressing portions 15 and 16 are attached to the tips of the upper and lower support arms 13 and 14 so as to face the electronic component mounting position P. The base ends of the upper and lower support arms 13 and 14 are supported by a three-dimensional drive mechanism 17 in the frame 1. The upper and lower pressing portions 15, 16 are movable in the front-rear direction, the left-right direction, and the up-down direction.

Substrate recognition cameras 18 and 19 are attached to the frame 1 above and below the electronic component mounting position P, respectively. When the substrate 7 stops at the electronic component mounting position P, the upper and lower substrate recognition cameras 18 and 19 detect the front surface 7a and the rear surface 7b of the substrate 7.

As shown in FIG. 2, an upper wafer stocker 20 is provided on the frame 1 adjacent to the substrate supply side stocker 2, and a lower wafer side stocker 21 is provided on the substrate discharge side stocker. 3, the upper and lower wafer transfer conveyors 22 are disposed between the stockers 20 and 21. In the upper and lower wafer transfer conveyors 22, both timing belts 23 are stretched between the stockers 20 and 21,
A plurality of gripping claws 24 are attached to the timing belts 23 at equal intervals and face each other. Then, the wafers 25 in the upper and lower wafer stockers 20, 21 are sandwiched by the gripping claws 24 of the timing belts 23, sent to the electronic component take-out position Q on the wafer transfer conveyor 22, and stopped at the same position Q. It has become.

Upper and lower wafer positioning portions 26 are provided in correspondence with the electronic component take-out position Q. In this wafer positioning unit 26, a chuck 27 that can be opened and closed
Are supported by the three-dimensional direction drive mechanism 28. And
The wafer 25 sandwiched between the grip claws 24 of the timing belts 23 at the electronic component take-out position Q is transferred to the chuck 27 as shown in FIG.

Upper and lower push-up needles 29 are supported by an elevating mechanism 30 between the upper and lower wafer positioning portions 26. The push-up needle 29 is adapted to move in the up-and-down direction to approach and separate from the wafer 25 on the chuck 27. Wafer recognition cameras 31 and 32 are attached to the frame 1 above and below the electronic component take-out position Q, respectively. The wafer recognition cameras 31, 32 detect the wafer 25 on the chuck 27.

Then, the wafer 25 on the chuck 27 is transferred again to the holding claws 24 of both timing belts 23 and returned to the wafer stockers 20, 21 to hold the holding claws 2.
It is designed to move away from 4.

Next, the bonding action with respect to the substrate 7 will be described separately for double-sided mounting and single-sided mounting. Wafer 25
When the upper electronic component (semiconductor chip) 33 is mounted on the front and back surfaces 7a and 7b of the substrate 7, the substrate 7 and the wafer 2
5 is specified, the substrate 7 is positioned at the electronic component mounting position P and the upper and lower wafers 25 are positioned on the chuck 27 at the electronic component take-out position Q as described above. Further, by specifying them, the upper and lower bonding arms 8 and 9, the upper and lower support arms 13 and 14, the upper and lower chucks 27, and the upper and lower push-up needles 29 are driven as preset. When the substrate 7 and the upper and lower wafers 25 are detected by the upper and lower substrate recognition cameras 18 and 19 and the upper and lower wafer recognition cameras 31 and 32, the upper and lower bonding arms 8 and 9 and the upper and lower bonding arms 8 and 9 are adjusted in accordance with the displacement of the substrate 7 from a predetermined position. The movements of both support arms 13 and 14 are corrected, and the movements of both upper and lower chucks 27 are corrected according to the displacement of wafer 25 from the expected position.

As shown in FIG. 4, the suction collets 10 and 11 on the upper and lower bonding arms 8 and 9 approach the wafer 25 on the upper and lower chucks 27 and start sucking a predetermined electronic component 33, Both push-up needles 29 separate the electronic component 33 from the wafer 25. Electronic component 3
Both the upper and lower suction collets 10 and 11 that have sucked 3 approach the front and back surfaces 7a and 7b of the substrate 7 as shown in FIG.

As shown in FIG. 5, the holding portions 15 and 16 on the upper and lower support arms 13 and 14 have front and back surfaces 7a of the substrate 7, respectively.
Support 7b. Regarding the supporting position, the electronic component 33
Set as close as possible to the mounting position of. The pressing portions 15 and 16 are made of a flexible material because they may come into contact with the electronic component 33 on the substrate 7. The mounting order of the electronic components 33 on the front and back surfaces 7a and 7b of the substrate 7 is set so as to prevent the contact between the suction collets 10 and 11 and the pressing portions 15 and 16.

The electronic components 33 on the upper and lower suction collets 10 and 11 are applied to the front and back surfaces 7a and 7b of the substrate 7, and are sealed with an adhesive paste or the like. This time,
The upper and lower pressing portions 15 and 16 prevent the board 7 from bending.

In order to prevent the substrate 7 from bending without using the pressing portions 15 and 16, as shown in FIG. 6, the upper and lower suction collets 10 and 11 are brought as close to each other as possible, and one of them is held at the other. Also serves as a retainer for objects. If it is not necessary to consider the flexure of the substrate 7, the upper and lower suction collets 10, 11 may be separated from each other.

When mounting the electronic component (semiconductor chip) 33 only on the front surface 7a or the back surface 7b of the substrate 7, for example, when mounting on the front surface 7a of the substrate 7, as shown in FIG. Supports the substrate 7 or FIG.
As shown in (a), the lower suction collet 11 is also used as a holding portion to support the substrate 7. Also in mounting on the back surface 7b of the substrate 7, as shown in FIG. 7 (b) or FIG. 8 (b),
Do the same. If it is not necessary to consider the bending of the substrate 7, such support is not provided.

Particularly in this embodiment, the front and back surfaces 7 of the substrate 7 are
In the bonding of the electronic component 33 to a and 7b, the mounting suction collet 10 on the front surface 7a and the back surface 7b
It is greatly different from the conventional device in that it is provided with a suction collet 11 for mounting on. Therefore, by using these suction collets 10 and 11, both front and back surfaces 7 of the substrate 7
The electronic component 33 can be simultaneously mounted on a and 7b, and the mounting time can be shortened. Further, unlike the conventional case, it is not necessary to turn the substrate 7 upside down, and the quality of the substrate 7 can be maintained and the reliability can be improved.

In another embodiment shown in FIG. 9, suction cylinders 35 are attached to both upper and lower suction arms 34 that can move in the front-rear direction, left-right direction, and up-down direction, and the upper and lower suction collets 10 and 11 are mounted on the substrate. It is designed to be inserted into the suction cylinder 35 when approaching the front and back both surfaces 7a, 7b of No. 7. Then, the suction cylinder 35 sucks the substrate 7 to suck the substrate 7.
Is prevented, and the electronic component 33 on the suction collets 10 and 11 is mounted on the substrate 7 in that state.

In another embodiment shown in FIG. 10, in FIG.
6 is different from the case shown in FIG. 2 in that the substrate 7 at the electronic component mounting position P is in an upright state, and accordingly, the bonding arms 8 and 9 and the support arms 13 and 14 are matched.
The board recognition cameras 18 and 19 have been changed. In particular, the rotary arms 8a, 9a, 13a, 14a are supported by the tip ends of the arms 8, 9, 13, 14 and the suction collets 10, 11 are attached to the rotary arms 8a, 9a on the bonding arms 8, 9, respectively. In addition to being attached, the pressing portions 15 and 16 are attached to the rotating arms 13a and 14a on the support arms 13 and 14, respectively. Then, the rotating arms 8a, 9a, 13a, 14a rotate in the range of 90 degrees, and the suction collets 10, 11 and the pressing portions 15, 16 are rotated.
Can face both front and back surfaces 7a and 7b of the substrate 7.

In another embodiment shown in FIG. 11, in FIG.
Compared with the case shown in Figure 2, both upper and lower wafer transfer conveyors 2
A plurality of wafers 25 are placed on the upper and lower wafer stockers 2
The wafers 25 are taken out from the wafers 0 and 21 and arranged side by side, and one of the wafers 25 is located at the electronic component taking-out position Q. Therefore, compared with the case where the necessary wafers 25 are taken out from the wafer stockers 20 and 21 one by one, the time can be further shortened.

As described above, the electronic component 33 is sealed on both the front and back surfaces 7a and 7b of the substrate 7 with an adhesive paste or the like. In order to prevent the electronic component 33 from dropping from the substrate 7 after the sealing. In addition, it is effective to use an adhesive having a high viscosity or an adhesive having a strong adhesive force. When mounting on the heatable substrate 7, if the electronic component 33 is mounted after heating the substrate 7, the adhesive is hardened and the adhesive force is increased. When the substrate 7 is heated, the chuck 27 for holding the substrate 7, the support pressing portions 15 and 16 of the substrate 7 or the suction collets 10 and 11 are heated to transfer the heat to the substrate 7 or the suction collet 10. , 11 to heat the electronic component 33 to cure the adhesive by the heat, or to irradiate the substrate 7 with laser or infrared rays. In addition, as shown in FIG. 12, the suction collets 10 and 11 are attached to the heating cylinder 3 on the heating arm 36.
The suction collets 10 and 11 are inserted into the inside 7 and hot air is blown to them.

Although not shown, both front and back surfaces 7a, 7 of the substrate 7
When the electronic component 33 is mounted on b, the electronic component 33 on the front surface 7a side is a semiconductor chip as described above, and the electronic component 33 on the back surface 7b side is a chip capacitor, a chip resistor, or the like. In this case, in FIGS. 1 and 2, the lower wafer stocker 21, the wafer transfer conveyor 22, the wafer positioning unit 26, and the like are changed to use a tape feeder that sucks a chip capacitor and sends it by tape.
The lower push-up needle 29 and the recognition camera 32 are not always necessary. In addition, an adhesive paste or the like is applied to the surface 7a of the substrate 7.
The side and the back surface 7b side can be used properly.

In this way, the electronic component 33 has the front and back surfaces 7
Although not shown, the substrate 7 bonded to a and 7b is placed on a lead frame and resin-molded,
Enclosed in the package. Generally within a package,
Due to the thermal cycle, peeling easily occurs between the substrate, the electronic component, and the package. In particular, when electronic components are mounted only on the front surface of the board, stress is relieved when peeling occurs on the front surface side, and stress concentrates on the back surface where peeling does not easily occur because electronic components are not mounted. To do. Therefore,
Even if the package is thick on the back side where there are no electronic components, package cracking is likely to occur. However, when the electronic components 33 are mounted on the front and back surfaces 7a and 7b of the substrate 7 as in this embodiment, if the peeling occurs evenly on the front and back surfaces 7a and 7b, stress concentration does not occur in either case. , Even if the package is thin, it does not easily crack. For this reason, double-sided mounting on the substrate 7 is effective as a measure against package cracking.

[0031]

According to the die bonding apparatus of the present invention, electronic components can be mounted from both front and back sides of the substrate, so that the mounting time can be shortened and the quality of the electronic component mounting substrate can be maintained. The reliability can be improved.

[Brief description of drawings]

FIG. 1 is a schematic partial front view showing a die bonding apparatus according to this embodiment.

FIG. 2 is a schematic partial plan view of the same.

3A is a partial front view showing a state in which the wafer is transferred to a wafer positioning portion at the electronic component take-out position from the state shown in FIG. 1, and FIG.
It is an A line partial sectional view, (c) is a BB line partial sectional view of (a).

FIG. 4 is a partial front view showing a state where the upper and lower suction collets take out electronic components from the upper and lower wafers from the state shown in FIG. 3 (a).

FIG. 5 is an operation explanatory view showing an example in which electronic components are mounted on both front and back surfaces of a substrate by both upper and lower suction collets.

FIG. 6 is an operation explanatory view showing another example of the same.

FIG. 7 is an operation explanatory view showing an example in which electronic components are mounted only on the front surface or the back surface of the substrate.

FIG. 8 is an operation explanatory view showing another example of the same.

FIG. 9 is a diagram showing another embodiment of the board deflection preventing means.

FIG. 10 is a partial front view showing another embodiment in which the state of the board at the electronic component mounting position is changed.

FIG. 11 is a schematic partial plan view of the present apparatus showing another embodiment in which the means for taking out the wafer from the wafer stocker is changed.

FIG. 12 is a diagram showing another embodiment of the heating means for the substrate.

[Explanation of symbols]

Reference numeral 7 ... Substrate, 7a ... Front surface, 7b ... Back surface, 10 ... Upper suction collet as first collet, 11 ... Lower suction collet as second collet, 33 ... Electronic component.

Claims (1)

[Claims] 1. In a die bonding apparatus for mounting an electronic component on a substrate, a first collet that holds the electronic component and conveys it to a mounting position on the front surface of the substrate, and a second collet that conveys the electronic component to a mounting position on the back surface of the substrate. A die bonding apparatus for mounting electronic components on a substrate, comprising: