JP2000260914A - Bonder for integrated circuit package element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure sufficient bonding strength while employing a quick thermosetting adhesive where thermosetting progresses in a several seconds when the reinforcing plate of TAB(tape automated bonding) tape and the heat dissipation plate of a semiconductor chip are bonded to manufacture a BGA(ball grid array) integrated circuit package. SOLUTION: The bonder 10 comprises a pasting stage 14 independently from a thermosetting stage 24 and a reinforcing plate 5 coated with a not yet set thermosetting adhesive 8 is mounted, at first, on the pasting stage 14 and pasted to a heat dissipation plate 6 thus spreading the adhesive uniformly. The pasted reinforcing plate 5 and heat dissipation plate 6 are transferred to the thermosetting stage 24 of a hot press 16 where it is hot pressed by means of a hot press head 22 thus setting the adhesive 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for manufacturing a ball grid array (BGA) type integrated circuit package, and more particularly, to a method for manufacturing a ball grid array type integrated circuit package. The present invention relates to a joining device for joining a heat sink with a thermosetting adhesive.

[0002]

2. Description of the Related Art It is known to manufacture ball grid array type integrated circuit packages by a Tape Automated Bonding (TAB) method. In the TAB method, electrode pads formed on a semiconductor chip and external leads formed on a TAB tape are connected by thermocompression bonding without using a bonding wire. When the bonding is completed, the individual semiconductor chips 1 are sealed with a potting resin 2 as shown in FIG. 1A to protect inner leads of the semiconductor chips, and a long TAB on which a series of semiconductor chips 1 are mounted is mounted. Tape 3 is obtained. The TAB tape is then cut into integrated circuit chip units. Since the TAB tape 3 is formed of a flexible film, the adhesive 4
The TAB tape 3 is reinforced by bonding the reinforcing plate 5 to the TAB tape 3.

[0003] As shown in FIG.
A thermosetting adhesive 8 is applied to the reinforcing plate 5 fixed to the AB tape 3.
The heat radiating plate 6 is adhered by using, and both are mechanically joined. Further, a heat radiating plate (heat spreader) 6 for diffusing the heat generated by the heat is bonded to the semiconductor chip 1. This is an adhesive 7 containing a heat transfer agent such as silver paste.
This is performed using When the reinforcing plate 5 and the heat radiating plate 6 of the TAB tape 3 on which the semiconductor chip 1 is mounted are joined in this way, solder balls 9 called bumps are connected to external leads of the TAB tape as shown in FIG. Thus, a ball grid array type integrated circuit package is obtained. This integrated circuit package can be mounted on a substrate by thermocompression bonding the solder bumps 9 to the substrate.

[0004]

In the above-described manufacturing process of the ball grid array type integrated circuit package, the bonding between the reinforcing plate 5 and the heat radiating plate 6 by the thermosetting adhesive 8 is performed as follows.
The uncured thermosetting adhesive 8 is applied to the reinforcing plate 5, the heat radiating plate 6 is superimposed on the thermosetting adhesive 8, placed on a heat curing stage of a heating press, and pressurized while being heated by a heated pressure head. This is performed by curing the thermosetting adhesive 8.
During operation of the heating press, the temperature of the heat curing stage of the heating press rises with use due to contact with the heated pressure head.

By the way, in order to improve productivity,
As the thermosetting adhesive 8 for bonding the reinforcing plate 5 and the heat radiating plate 6, it is desirable to use a quick-curing adhesive that cures in a few seconds. However, when a rapid-curing thermosetting adhesive is used as described above, since the temperature of the heat-curing stage increases with use as described above, a reinforcing plate coated with an uncured adhesive is used. As soon as 5 is placed on the heat-curing stage of the heat press, the curing of the adhesive starts. As a result, the wetting of the adhesive to the reinforcing plate 5 and the heat radiating plate 6 becomes uneven, the adhesive is not sufficiently spread, and the bonding area becomes insufficient, and the bonding strength becomes insufficient or the bonding strength varies.

SUMMARY OF THE INVENTION An object of the present invention is to bond a reinforcing plate of a TAB tape and a heat sink of a semiconductor chip using a thermosetting adhesive, while improving the productivity and improving the adhesive strength between the reinforcing plate and the heat sink. To improve the uniformity.

[0007]

SUMMARY OF THE INVENTION The present invention provides a bonding apparatus for bonding a TAB tape reinforcing plate and a heat radiating plate of a package with a thermosetting adhesive in manufacturing a ball grid array type integrated circuit package. In this apparatus, a bonding stage for bonding the reinforcing plate coated with the uncured thermosetting adhesive and the heat radiating plate in advance prior to heating, and the reinforcing member bonded by the uncured adhesive are used. A heat curing stage for mounting a plate and a heat radiating plate, and a heating press having a heated pressure head are provided.

In the apparatus of the present invention, since the bonding stage is provided separately from the heat-curing stage of the heating press, the bonding stage does not come into contact with the pressing head of the heating press, and is heated by the pressing head. Never be. Therefore, the bonding stage is always kept at a low temperature. When joining the reinforcing plate and the heat sink,
A reinforcing plate to which an uncured thermosetting adhesive has been applied is placed on this bonding stage, a heat radiating plate is superimposed on the reinforcing plate, and pressure is applied to both to preliminarily bond them before heating. Since the bonding stage is maintained at a low temperature, the curing of the thermosetting adhesive does not start in this bonding step, and the adhesive is sufficiently spread. As described later with reference to the drawings, preferably, the adhesive is scribed by slightly swinging the heat radiating plate while applying pressure to the heat radiating plate, thereby eliminating uneven coating of the adhesive and uniformly dispersing the adhesive. Spread it.

In a preferred embodiment, the bonding apparatus includes a transfer mechanism for transferring the reinforcing plate and the heat radiating plate bonded by the uncured adhesive from the bonding stage to the heat curing stage. And a clamp mechanism for clamping the reinforcing plate and the heat radiating plate bonded by the uncured adhesive to each other.

[0010] In another embodiment, the heat-curing stage includes a positioning pin for positioning the reinforcing plate and the heat sink with respect to each other. Further, in a preferred embodiment, the heat-curing stage is elastically supported so as to uniformly press the reinforcing plate and the heat radiating plate.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 2 to 4, a joining apparatus 10 of the present invention for joining a reinforcing plate of a TAB tape of a ball grid array type integrated circuit package and a heat radiating plate of a semiconductor chip is provided. A machine base 12, a bonding stage 14 fixed to the machine base 12, a heating press 16
And a transfer mechanism 18 for transferring the work from the bonding stage 14 to the heating press 16. The heating press 16 includes a pressure head 22 having a built-in heater 20;
It has a heat curing stage 24. Heat curing stage 24
Is mounted on a slider 28 slidably mounted on a horizontal guide rail 26 so as to move between an operating position below the pressure head 22 and a non-operating position indicated by a solid line in FIG. Has become. The pressure head 22 includes the slider 3
0 on a movable block 34 slidably guided by a vertical guide rail 32,
6 move up and down.

The transfer mechanism 18 has a transfer hand 38.
The transport hand 38 is mounted on a slider 42 that slides along a vertical guide rail 40,
4 is moved vertically. Vertical guide rail 4
0 itself is mounted on a slider 48 guided by a horizontal guide rail 46. By operating an air cylinder built in the guide rail 46, the transport hand 38 moves in a horizontal direction between a position above the bonding stage 14 and a position above the heat curing stage 24 at the non-operation position. A clamp mechanism 50 is mounted on the transport hand 38. As shown in FIG. 4, the clamp mechanism 50 includes a top plate 52 and a pair of clamps 56 each driven by a cylinder 54.

Next, the mode of operation and use of the joining device 10 will be described. In order to improve work efficiency, the reinforcing plate 5 and the heat radiating plate 6 to be joined can be formed in the form of, for example, four-piece frames 58 and 60 as shown in FIGS. . As shown in FIG. 6, the reinforcing plate frame 58 to be joined has a potting resin 2
The individual TAB tapes 3 each having the semiconductor chip 1 sealed with are previously bonded. As shown in FIGS. 5 and 6, positioning pin holes 62 are formed in the heat-radiating plate frame 60 and the reinforcing plate frame 58 in diagonal directions, and the heat-curing stage 24 is formed as shown in FIG. A pair of positioning pins 64 are arranged corresponding to these pin holes 62.

Prior to the joining process by the joining device 10,
The uncured thermosetting adhesive 8 and the silver paste-containing adhesive 7 are applied to the upper surface of the reinforcing plate frame 58 as shown in FIG. The application of the adhesive 8 is performed by extruding the adhesive from a nozzle of the dispenser. The operator places the reinforcing plate frame 58 on which the thermosetting adhesive 8 and the silver paste-containing adhesive 7 are applied in advance on the bonding stage 14 of the joining device 10, and places the heat sink frame on the reinforcing plate frame 58. The reinforcing plate frame 58 and the heat radiating plate frame 60 are attached to each other by stacking 60.

The pattern of the adhesive 8 applied to the upper surface of the reinforcing plate frame 58 by extrusion from the nozzle is shown in FIG.
As shown in an enlarged manner in (A), it may not always be uniform. Therefore, when the heat radiating plate frame 60 is overlaid on the reinforcing plate frame 58 and pressed, the pattern of the adhesive 8 may be non-uniform as shown in FIG. 9B. Therefore, preferably, the worker scribes the adhesive by slightly swinging the heat radiating plate frame 60 back and forth and right and left with a finger as shown by an arrow 66 in FIG. 8, and as shown in FIG. 9C. Spread the adhesive evenly. Since the bonding stage 14 does not come into contact with the pressure head 22 of the heating press 16 and is not heated by the pressure head 22, the bonding stage 14
Is maintained at room temperature. Therefore, the curing of the adhesive does not start while the adhesive is scribed. The scribing of the adhesive becomes possible by providing the bonding stage 14 separately from the heat curing stage 24 having a high temperature.

When the reinforcing plate frame 58 and the radiator plate frame 60 have been bonded on the bonding stage 14, the positioning member is attached to the assembly of the reinforcing plate frame 58 and the radiator plate frame 60 as shown in FIG. Position the assembly by hitting 68 and 70. Next, by operating the clamp 56 of the clamp mechanism 50, FIG.
As shown in (1), the assembly is clamped, and the air cylinder of the transfer mechanism 18 is operated to move the transfer hand 38 above the heat curing stage 24, and then lower the transfer hand 38. Positioning pins 64 of the heat curing stage 24
Are engaged with the pin holes 62 of the reinforcing plate frame 58 and the heat sink frame 60, and the assembly of the reinforcing plate frame 58 and the heat sink frame 60 is positioned on the heat curing stage 24.

Next, the heat curing stage 24 is moved below the pressure head 22, and the pressure cylinder 36 is operated.
The pressure head 22 heated by the heater 20 presses the assembly of the reinforcing plate frame 58 and the radiating plate frame 60 to press the assembly.
By heating, the thermosetting adhesive 8 and the silver paste-containing adhesive 7 are cured. The intermediate product of the integrated circuit package thus obtained is sent to the next step.

FIG. 10 shows a variation of the heat curing stage 24. In this variation, the heat curing stage 24
A includes a base 72 and a height control plate 74, and guide pins 78 for supporting a work mounting plate 76 are slidably inserted through the base 72. Base 72 and work mounting plate 7
6, a spring 80 is arranged, and the work mounting plate 7
6 is elastically supported. This heat curing stage 24
When the pressure head 22 descends, when the pressure head 22 comes into contact with the radiator plate frame 60 of the assembly of the reinforcing plate frame 58 and the radiator plate frame 60 mounted on the heat curing stage 24A, the work Since the mounting plate 76 retreats against the action of the spring 80, the heat sink frame 60 is held parallel to the pressure head 22. Pressure head 22
Is regulated by a height control plate 74. In the heat-curing stage 24A, the radiator plate frame 60 is held parallel to the pressure head 22, so that the adhesive can be pressed uniformly. The pressure applied to the reinforcing plate and the heat sink is a value obtained by subtracting the weight of the work mounting plate 76 from the load of the spring 80. Therefore, it is possible to change the pressing force by changing the spring force of the spring 80.

[0019]

According to the apparatus of the present invention, since the bonding between the reinforcing plate and the heat sink of the integrated circuit package is performed on the bonding stage maintained at a low temperature, rapid hardening proceeds in a few seconds. Even when a mold-type thermosetting adhesive is used, the adhesive can be spread uniformly over a sufficient area. In addition, it is possible to scribe the adhesive on the bonding stage as needed, and it is possible to eliminate uneven application of the adhesive. Therefore, the mechanical bonding strength between the reinforcing plate and the heat sink can be improved, and the heat conduction between the semiconductor chip and the heat sink can be promoted.

In the embodiment in which the clamp mechanism is provided in the transfer mechanism, it is possible to prevent the displacement between the reinforcing plate and the heat radiating plate bonded by the uncured adhesive. In the embodiment in which the heat curing stage is elastically supported, the pressing force can be made uniform.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a general manufacturing process of a ball grid array type integrated circuit package.

FIG. 2 is a front view of the joining device of the present invention.

FIG. 3 is a side view of the hot press taken along the line II-II of FIG. 2;

4 is a side view of a clamp mechanism of the device shown in FIG.

FIG. 5 is a plan view of a heat sink frame joined by the joining apparatus of the present invention.

FIG. 6 is a plan view of a reinforcing plate frame joined by the joining device of the present invention.

FIG. 7 is a plan view showing a state where an adhesive is applied to the reinforcing plate frame shown in FIG. 6;

FIG. 8 is a plan view showing a state in which a radiator plate frame laid on a reinforcing plate frame is swung.

FIG. 9 is a plan view showing a pattern of an adhesive applied to a reinforcing plate frame.

FIG. 10 is a cross-sectional view showing a variation of the heat curing stage;
(A) shows the position when no pressure is applied, and (B) shows the position when pressure is applied.

[Explanation of symbols]

 1: semiconductor chip of BGA type integrated circuit package 2: potting resin 3: TAB tape of BGA type integrated circuit package 5: reinforcing plate of BGA type integrated circuit package 6: heat sink of BGA type integrated circuit package 10: joining device 14: Laminating stage 16: Heat press 18: Transfer mechanism 22: Pressurizing head 24: Heat curing stage 50: Clamp mechanism 64: Positioning pin

Claims (5)

[Claims] 1. A joining device for joining a reinforcing plate of a TAB tape and a heat radiating plate of a package of a ball grid array type integrated circuit package with a thermosetting adhesive in the manufacture of the package. A bonding stage for bonding the reinforcing plate and the radiator plate to which the adhesive has been applied in advance prior to heating, and heat curing for placing the reinforcing plate and the radiator plate thus bonded by the uncured adhesive A bonding apparatus comprising a stage and a heating press having a heated pressure head. 2. The apparatus according to claim 1, further comprising a transfer mechanism for transferring the reinforcing plate and the heat sink bonded by the uncured adhesive from the bonding stage to the heat curing stage. Joining equipment. 3. The bonding apparatus according to claim 2, wherein the transfer mechanism includes a means for clamping the reinforcing plate and the heat radiating plate bonded by the uncured adhesive to each other. 4. The bonding apparatus according to claim 1, wherein the heat curing stage includes a positioning pin for positioning the reinforcing plate and the heat radiating plate relative to each other. 5. The heat curing stage according to claim 1, wherein the heat curing stage is elastically supported by a machine base so as to uniformly press the reinforcing plate and the heat radiating plate. Based joining equipment.