JPH0758499A - Method and device for mounting electronic part - Google Patents

Abstract

PURPOSE:To provide an electronic part mounting method by which the part mounting time can be shortened by simultaneously performing thermocompression bonding of all electronic parts. CONSTITUTION:In an electronic part mounting method in which electronic parts 5 are mounted on a printed wiring board 1 by thermocompression bonding and curing a bonding agent interposed between the board 1 and parts 5 while the parts 5 are placed on the board 1, the thermocompression bonding is performed after tentatively fixing the parts 5 to be mounted at a prescribed position on the board 1. The tentatively fixing method includes a method using air suction, a method in which the parts 5 are stuck to the board 1 at the end section of a sheet- or belt-like tentatively fixing means by putting the tentatively fixing means on the parts 5, a method using weights, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for mounting electronic components on a printed wiring board, and more particularly to a method and apparatus for mounting electronic components using an adhesive.

[0002]

2. Description of the Related Art FIG. 6 is a flow chart showing a procedure for fixing a bare chip (electronic component) to a printed wiring board using a conductive adhesive.

Gold bumps 51 are formed on a pad formed on the back surface of a semiconductor component 5s as an electronic component by using a bonder capillary 70, and the bumps 51 are pressed against the flat plate 2 to make the bump height uniform. (FIG. 6, step a →
b).

Next, the bumps 51 of the semiconductor component 5s are brought into contact with the conductive adhesive Ba spread on the glass plate 3 to transfer the conductive adhesive Ba to the bumps 51 and the printed wiring board 1 The insulative adhesive Bb is printed on the upper part arrangement position (FIG. 6, steps c → d). Finally, the semiconductor component 5s is heated under pressure (20 to 30 g / bump) (for example, at 200 ° C. for 30 seconds) to thermally cure the conductive and insulating adhesives (FIG. 6, FIG. Step e).

FIG. 7 shows a time chart of the thermocompression bonding process. Simultaneously with the start of heating, pressure is applied at a pressure of about 20 to 30 g / bump, and when the temperature reaches 200 ° C., it is maintained for about 30 seconds. After that, the temperature is cooled to about room temperature and the pressure is reduced.

[0006]

The time required for the temperature to reach 200 ° C. or the time required for the temperature to drop from 200 ° C. to room temperature varies depending on the capability of the apparatus, but it is an average until the mounting of one component is completed. The time is about 3 to 5 minutes.

Therefore, it takes a considerable time to thermocompression-bond a large number of electronic components, which is a factor of deteriorating workability. The present invention has been proposed in view of the above conventional circumstances, and provides a mounting method of an electronic component capable of reducing the component mounting time by performing the thermocompression bonding process for all electronic components at once. It is intended to be provided.

[0008]

The present invention employs the following means in order to achieve the above object. That is, in a mounting method of an electronic component, an electronic component is mounted on a printed wiring board, and an adhesive interposed between the electronic component and the printed wiring board is thermocompression-bonded and cured. After the component is temporarily fixed at a predetermined position on the printed wiring board, thermocompression bonding is performed.

For example, as shown in FIGS. 1 and 2, the electronic component 5 is mounted at the component mounting position of the printed wiring board 1 having the component mounting hole 11 at the component mounting position, and the electronic component 5 is mounted at the component mounting hole. By sucking from the back surface of the printed wiring board 1 via 11, the electronic component 5 is temporarily fixed to the printed wiring board 1.

In order to carry out the temporary fixing by adsorption,
As shown in FIG. 1, the printed wiring board 1 is provided on the upper surface of the housing 21.
The mounting table 20 is provided with the opening 22 corresponding to the size and the suction table 23 is provided at at least one position on the periphery of the mounting apparatus.

Alternatively, as shown in FIGS. 3 and 4, when the electronic component 5 is placed on the printed wiring board 1, a sheet-like or band-like temporary fixing means 52 which is covered from above the electronic component 5 is provided. The electronic components 5 are temporarily fixed to the printed wiring board 1 by temporarily fixing both ends of the to the printed wiring board 1 with an adhesive or the like.

Further, as shown in FIG. 5, when the electronic component 5 is placed on the printed wiring board 1, a weight 6 is placed on the electronic component 5 to temporarily fix the electronic component 5 on the printed wiring board 1. It After temporarily fixing all electronic components 5 to be adhesively fixed on the printed wiring board 1 as described above, thermocompression bonding processing is performed on the all electronic components 5.

[0013]

Function: The height of the bump of the electronic component 5 is at most 60 μm
As shown in FIGS. 1 and 2, when the electronic component 5 is placed on the printed wiring board 1 and sucked through the component suction holes 11, there is a slight air bleeding from the periphery, but temporary temporary fixing. Will be possible.

Further, as shown in FIGS. 3 and 4, an adhesive Bc is applied to both ends of a sheet-like or band-like temporary fixing means 52 covered with the electronic component 5, and both ends of the temporary fixing means 52 are applied. By adhering to the printed wiring board 1, the electronic component 5 can be temporarily fixed to the printed wiring board 1 at room temperature.

Furthermore, as shown in FIG. 5, when the electronic component 5 is placed on the printed wiring board, a weight having a predetermined weight is placed on the upper side of the electronic component 5, so that the weight of the electronic component 5 is equal to the weight of the electronic component 5. Can be temporarily fixed to the printed wiring board.

By the temporary fixing as described above, a large number of electronic components 5 placed on the printed wiring board 1 are simultaneously thermocompression-bonded to the printed wiring board.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a flow chart showing a part of the procedure according to the present invention, and FIG. 2 (a) is an external perspective view of a component mounting table embodying the present invention, and FIG. ) Is a sectional view thereof.

An opening 22 having a size corresponding to the printed wiring board 1 is provided on the upper surface of the housing 21, and the housing 2 is provided.
At least one suction port 23 is provided on the peripheral surface of 1.
On the other hand, a suction hole 11 is opened in the center of the component disposition position of the printed wiring board 1 and is placed in the opening 22 of the housing 21, and as shown in FIG.
Block with 3. In this state, the sheet piece 13 at the mounting target component position is peeled off while sucking air through the suction port 23, and the head of the conventional electronic component mounting apparatus (no pressure or heating function is required) is used to electrically conductive the lower surface of the bump. Place an electronic component (see Fig. 6 (c)) with a conductive adhesive (Fig. 1 (a))
).

In addition, the insulating adhesive which has been conventionally applied before placing electronic components on the printed wiring board side is the same as in the conventional process (see FIG. 6 (d)). 1 is applied. However, since the suction hole 11 is opened in the center as described above, it is applied only to the peripheral portion.

The electronic components 5 are sequentially placed as described above, and thermocompression bonding having the size of the printed wiring board 1 is performed with all the electronic components 5 to be mounted by the adhesive method being placed. The head 30 simultaneously thermocompresses and fixes all the electronic components 5 on the printed wiring board 1.

In the above example, the insulating adhesive is applied until the electronic component 5 is placed on the printed wiring board 1. However, the electronic adhesive is applied to the printed wiring board 1 without applying the insulating adhesive. Temporarily placing the component 5, the thermocompression bonding head 30
When there is no danger of the electronic components 5 moving by pressing all the electronic components 5, the nozzles are inserted between the printed wiring board 1 and the thermocompression bonding head 30 so that the electronic components 5 and the printed wiring board 1 are connected to each other. You may make it blow an insulating adhesive agent on.

FIG. 3 is a conceptual diagram showing an electronic component used in another embodiment of the present invention, and FIG. 4 shows an embodiment of the present invention using the electronic component 5. First, electronic component 5
As shown in FIG. 3 (a), (b) or (c), a sheet-shaped body or a strip-shaped body (belt-shaped body) which is long in one direction or both directions of the electronic component 5 by a length corresponding to the height of the electronic component 5 A temporary fixing means 52 (hereinafter simply referred to as a sheet) is attached, and the adhesive Bc is applied to the end portion of the temporary fixing means 52.

The electronic component 5 to which the temporary fixing means 52 is attached in this way is attracted by the head 60 of the component mounting apparatus, and the bumps on the lower surface of the electronic component 5 are electrically conductive as shown in FIG. The adhesive is transferred and then placed at a predetermined position on the printed wiring board 1 as shown in FIG. 4 (a).

Further, as shown in FIG. 4 (b), the adhesive-coated portions at both ends of the temporary fixing means 52 are pressed and adhered to the printed wiring board 1 to temporarily mount the electronic component 5 on the printed wiring board 1. Fix it. As a result, the state where the electronic component 5 is lightly pressed against the printed wiring board 1 can be maintained.

Although the temporary fixing means 52 is previously attached to the electronic component 5 in the above description, the sheet-shaped body or the belt-shaped body as the temporary fixing means 52 is sandwiched between the electronic component 5 and the head 60 of the mounting apparatus. May be set to.
In this case, in the sheet-shaped body shown in FIGS. 3 (a) and 3 (b), it is necessary to form a hole at a position corresponding to the upper surface of the sheet-shaped body so as not to prevent the head 60 from sucking the electronic component. .

In order to bond both ends of the temporary fixing means 52 to the printed wiring board 1, the head 60 of the electronic component mounting apparatus lightly presses the electronic component 5 against the printed wiring board 1 as shown in FIG. ), The temporary fixing means 52
Jig 6 for pressing both ends of the board to the printed wiring board 1
It is preferable that the head 60 and the pressing jig 62 be operated in association with each other in the mounting apparatus with No. 2 provided.

As described above, the individual electronic components 5 are temporarily fixed, and when all the electronic components are temporarily fixed, the thermocompression bonding head 30 thermocompresses all the electronic components at once (FIG. 4).
(c)).

Also in the above embodiment, the insulating adhesive to be applied to the printed wiring board side may be printed before the electronic component 5 is placed on the printed wiring board 1 as in the first embodiment. Alternatively, after the temporary fixing is completed by the temporary fixing means 52, a nozzle or the like may be used to blow from between the printed wiring board 1 and the electronic component 5.

FIG. 5 is a flow chart showing still another embodiment of the present invention. As shown in FIG. 5 (a), when the electronic component 5 is sucked and aligned by the head 60 of the electronic component mounting apparatus, the electronic component 5 and the head 6 of the electronic component mounting apparatus are aligned.
The weight 6 is interposed between the weight 0 and the zero. This weight 6 has ventilation holes 61
When the head is opened, the head 60 can suck the electronic component 5.

After the conductive adhesive is transferred to the bumps 51 of the electronic component 5 (see FIG. 6C) while the components are absorbed by the head 60, the electronic component 5 is attached to the insulating adhesive B.
When temporarily placed while applying pressure to a predetermined position on the printed wiring board 1 coated with b, the weight 6 is also placed on the electronic component 5, and the electronic component 5 is the weight of the weight 6 and the printed wiring board 1 It will be temporarily fixed on top (Fig. 5 (b) → (c) →
(d)). In this way, when the electronic components 5 are sequentially placed on the printed wiring board 1 and all the electronic components 5 are placed,
The entire printed wiring board 1 is passed through the heating area 7,
After this, the weight 6 is removed (FIG. 5 (e) → (f)). If a sufficient weight cannot be obtained with the weight 6 alone,
Instead of the heating area passage processing, the thermocompression bonding head 30 having a heating and pressurizing function similar to the two embodiments is used to perform the thermocompression bonding processing. As a result, the printed wiring board 1 and all the electronic components 5 to be mounted on the printed wiring board 1 with an adhesive are fixed by a single thermocompression bonding process.

In the suction method and the mounting method using the temporary fixing means 52, both the heat treatment and the pressure treatment are performed using the thermocompression bonding head 30.
It may have only a pressurizing function, and heating may be performed from outside of the head 30.

The thermocompression bonding head 3 is used in the above three embodiments.
When 0 (including the case of only the pressurizing function) is used and the height of each electronic component 5 is not uniform, a spacer is placed on the electronic component 5 having a low height (or on the lower surface of the head 30). Are interposed so that all electronic components 5 have the same height.

[0033]

As described above, according to the present invention, the electronic component is temporarily fixed on the printed wiring board and then the adhesive is cured by the thermocompression bonding head, so that the electronic component is mounted on the printed wiring board in advance. After temporarily fixing all the electronic components to be subjected, the thermocompression bonding process can be performed on the all electronic components, and the thermocompression bonding process can be performed only once, so that the manufacturing time and the cost can be reduced. .

[Brief description of drawings]

FIG. 1 is a flow chart showing an implementation procedure of the present invention to which an adsorption method is applied.

2A and 2B are a perspective view and a cross-sectional view showing an embodiment of a mounting table used for a suction method.

FIG. 3 is a perspective view showing an electronic component used in a bonding method.

FIG. 4 is a flow chart showing a procedure for carrying out the present invention to which an adhesive system is applied.

FIG. 5 is a flow chart showing an implementation procedure of the present invention showing a weighting method.

FIG. 6 is a flowchart of a conventional example.

FIG. 7 is a time chart of a conventional example.

[Explanation of symbols]

 1 Printed Wiring Board 5 Electronic Component 6 Weight 11 Component Suction Hole 20 Mounting Table 21 Housing 22 Opening 23 Suction Port 52 Temporary Fixing Means

Claims (6)

[Claims] 1. An electronic component (5) and a printed wiring board (1) in a state in which the electronic component (5) is placed on the printed wiring board (1).
In the mounting method for electronic components, in which the adhesive interposed between and is hardened by thermocompression bonding, the electronic component (5) to be mounted is temporarily fixed at a predetermined position on the printed wiring board (1) and then A method of mounting an electronic component, which comprises performing a crimping process. 2. An electronic component (5) at the component mounting position of a printed wiring board (1) having a component suction hole (11) at the component mounting position.
The electronic component (5) is temporarily fixed to the printed wiring board (1) by sucking it from the back surface of the printed wiring board (1) through the component suction hole (11) while the electronic component (5) is placed. Mounting method of electronic parts described in. 3. An end of a temporary fixing means (52) for a sheet-shaped body or a band-shaped body covered from above the electronic component (5) when the electronic component (5) is placed on the printed wiring board (1). The electronic component mounting method according to claim 1, wherein the electronic component (5) is temporarily fixed to the printed wiring board (1) by temporarily fixing the part to the printed wiring board (1). 4. When the electronic component (5) is placed on the printed wiring board (1), the weight (6) is placed on the electronic component (5) and the electronic component (5) is placed on the printed wiring board (1). 5. The method of mounting an electronic component according to claim 1, wherein 5) is temporarily fixed, and then the electronic component is heated to and pressurized as needed. 5. After temporarily fixing all electronic components (5) to be adhesively fixed on a printed wiring board (1), the all electronic components (5)
5. The method of mounting an electronic component according to claim 1, wherein thermocompression bonding is performed. 6. In order to carry out the method according to claim 2, an opening (22) corresponding to the size of the printed wiring board (1) is provided on the upper surface of the housing (21), and at least the surrounding area is provided. An electronic component mounting apparatus comprising a mounting table (20) having a suction port (23) at one location.