JP3055675B2 - Semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a ball grid array using a film carrier tape.
y; hereinafter, the ball grid array will be referred to as BGA) type semiconductor device, and more particularly, to a semiconductor device which prevents displacement when fixing a heat sink to a reinforcing plate.

[0002]

2. Description of the Related Art First, an example of the structure of a conventional general tape BGA will be described with reference to FIG. In this figure, (a) is a sectional view, and (b) is a bottom view.
As shown in FIG. 3, the tape BGA has a base film 1 as a substrate, and solder bumps 8 as external terminals are arranged on the base film 1 in a grid pattern. The wiring 2 is formed between the solder bump 8 and the electrode 6 of the semiconductor chip 5 by a copper foil or the like. In this wiring 2, the electrode 6
The side connected to the solder bumps 8 is called an inner lead 3, and the side connected to the solder bumps 8 is called a land 4. Although only one wiring is shown in FIG. 3B, it goes without saying that all solder bumps are actually connected to the electrodes of the semiconductor chip.

The base film 1 is easily warped because it is mainly composed of polyimide or the like. Therefore, on the surface of the base film 1 opposite to the surface on which the lands 4 are formed,
One surface of the reinforcing plate 9 is fixed by the adhesive 10. The reinforcing plate 9 is made of a material such as metal that is less likely to deform than the base film 1. Further, on another surface of the reinforcing plate 9, a heat radiating plate 11 for improving the heat radiation of the semiconductor chip 5 is provided with an adhesive having a high thermal conductivity (for example, an adhesive made of a heat-resistant epoxy resin such as alumina or alumina). A mixture of filler materials such as metal particles, which is hereinafter referred to as a heat conductive adhesive).

[0004] The semiconductor chip 5 is housed in a device hole 17 formed in the base film 1 and the reinforcing plate 9 and is sealed with a sealing resin 7.

[0005]

When the heat radiating plate 11 is fixed to the reinforcing plate 9 in the tape BGA having the structure as shown in FIG. 3, the bonding between the reinforcing plate 9 and the base film 1 is performed as shown in FIG. After applying the heat conductive adhesive 12 to the surface opposite to the surface and the surface opposite to the surface on which the electrodes 6 of the semiconductor chip 5 are provided, for example, using an adhesive application nozzle 13, heat is released. The plate 11 is placed, and the heat conductive adhesive 12 is cured. In this case, the heat conductive adhesive 12
If is a thermosetting adhesive, the heat sink 11 can be fixed by performing heat treatment.

However, since the heat conductive adhesive 12 is soft before being cured, the heat conductive adhesive 12 may be vibrated during transportation and the like.
As shown in FIG. 5, the heat sink 11 may be displaced from the reinforcing plate 9 and the base film 1. The present invention has been made in view of such a situation,
An object of the present invention is to realize prevention of positional deviation when a heat radiating plate is fixed to a reinforcing plate in a tape BGA.

[0007]

An object of the present invention is to provide a base film having a device hole formed therein, a reinforcing plate having a device hole formed therein, and a heat sink.
One main surface of the base film and one main surface of the reinforcing plate are fixed such that device holes thereof communicate with each other, and the other main surface of the reinforcing plate is fixed to one main surface of the heat radiating plate. In a semiconductor device in which a semiconductor chip is housed in a device hole, the problem can be solved by forming a displacement prevention member on the heat sink, which is in contact with a wall surface of the device hole.

According to the present invention, when the radiator plate is fixed to the reinforcing plate with an adhesive, the displacement preventing member formed on the radiator plate is dropped so as to be in contact with the wall surface of the device hole. With this configuration, even if a horizontal force is applied to the heat radiating plate due to vibration or the like at the time of conveyance, the side surface of the displacement preventing member abuts against the wall surface of the device hole of the reinforcing plate, thereby preventing the heat radiating plate from being displaced. I can do it.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings. [First Embodiment] FIG. 1 is a diagram showing a first embodiment of a semiconductor device according to the present invention. In this figure, FIG.
The same reference numerals are given to the parts corresponding to those in FIG. FIG. 1A is a plan view,
(B) is an AA sectional view in (a).

The semiconductor device shown in FIG.
A base film 1 having a function as a substrate on which the semiconductor chip 5 is mounted; a reinforcing plate 9 supporting the base film 1 for suppressing deformation of the base film 1; and a heat generated by the operation of the semiconductor chip 5. A heat radiating plate 11 for emitting to the outside. One main surface of the base film 1 and one main surface of the reinforcing plate 9 are fixed by an adhesive 10, and the other main surface of the reinforcing plate 9 and one main surface of the heat radiating plate 11 are fixed by a heat conductive adhesive 12. ing. In the present embodiment, the outer dimensions of the base film 1 match the outer dimensions of the reinforcing plate 9.

A device hole 17 is formed at the center of each of the reinforcing plate 9 and the base film 1, and the semiconductor chip 5 is accommodated therein. In the present embodiment, the device holes of the reinforcing plate 9 correspond to the base film 1.
Larger than the device hole. Electrode 6 of semiconductor chip 5 and reinforcing plate 9 of base film 1
The wiring 2 is electrically connected between the surface on which is fixed and the solder bumps 8 formed in a grid on the opposite surface.
A portion of the wiring 2 connected to the electrode 6 is called an inner lead 3, and a portion located between the solder bump 8 and the base film 1 is called a land 4. The semiconductor chip 5 housed in the device hole 17 is sealed with the resin 7.

The radiator plate 11 is made of, for example, a metal having good thermal conductivity. The opposite side to the surface on the side to be bonded to the reinforcing plate 9 so that the projections 15 are formed at the four opposing corners of the opening of the device hole 17 (the corners of the wall surface and the vicinity thereof). Are formed on the surface of the substrate. Each depression 14 has a thickness of 0.15 mm to 0.15 mm when the thickness of the thermally conductive adhesive 12 is 0.1 to 0.15 mm, for example.
Set to a depth of 0.2 mm. That is, the heat conductive adhesive 12
By making the length of the protrusion 15 longer than the thickness of the protrusion 15, the tip of the protrusion 15 is configured to contact the corner of the device hole 17 in the reinforcing plate 9. The depression 14 can be formed by applying a mechanical external force to the radiator plate 11 itself.

In the present embodiment, when the heat radiating plate 11 is fixed to the reinforcing plate 9 by the heat conductive adhesive 12, the heat radiating plate 11 is fixed.
Of the device hole 17 is dropped. In this case, even if a horizontal force is applied to the heat radiating plate 11 due to vibration during transportation or the like, the side surfaces of the projections 15 abut against the corners of the wall surfaces of the device holes 17 formed in the reinforcing plate 9, so that heat radiation Board 1
1 can be prevented from shifting.

[Second Embodiment] FIG. 2 is a diagram showing a second embodiment of the semiconductor device according to the present invention. In this figure, parts corresponding to those in FIG. 1 are denoted by the same reference numerals as those used in FIG. 2A is a bottom view, and FIG. 2B is a sectional view taken along line AA in FIG. As is clear from FIGS. 1 and 2, parts other than the structure of the radiator plate 11 in this embodiment are the same as those in the first embodiment shown in FIG. Is omitted.

Also in this embodiment, the radiator plate 11 is made of, for example, a metal having good heat conductivity. The edge of the opening of the device hole 17 and the portion facing the predetermined width inside the device hole 17 are left by the adhesive 18 so as to leave a rectangular frame-like member 16, that is, a predetermined width portion around the rectangular plate. A member having a hollow shape is fixed.
The frame member 16 is made of, for example, a hard synthetic resin. Then, for example, when the thickness of the heat conductive adhesive 12 is 0.1
When the thickness is 0.15 mm to 0.15 mm, the thickness of the frame-shaped member 16 is set to 0.
15 mm to 0.2 mm. That is, by forming the thickness of the frame-shaped member 16 to be larger than the thickness of the thermally conductive adhesive 12, the outer wall surface of the frame-shaped member 16 is Is configured to be in contact with the entire circumference.

In this embodiment, when the heat radiating plate 11 is fixed to the reinforcing plate 9 by the heat conductive adhesive 12, the frame-shaped member 1
6 is dropped so as to contact the outer wall surface of the device hole 17. In this way, even when a horizontal force is applied to the heat radiating plate 11 due to vibration during transportation or the like, the entire periphery of the outer wall surface of the frame-shaped member 16 abuts the entire periphery of the wall surface of the device hole 17 of the reinforcing plate 9. Therefore, the displacement of the heat sink 11 can be prevented. Here, the outer size of the frame-shaped member 16 is, for example, 0.1 mm larger than the size of the device hole 17 when the allowable range of the displacement of the heat sink 11 is 0.1 mm.
It is preferable to reduce the size within about mm.

It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made within the scope described in the claims. For example, in FIG. 1, the circular depression 14 is formed so as to face four corners of the device hole 17, but a depression facing the entire circumference of the device hole 17 may be formed. In this case, a projection similar to the frame-shaped member 16 in FIG. 3 is formed on the opposite side of the depression. Further, instead of the frame-shaped member 16 in FIG. 2, a columnar member or a prism-shaped member may be bonded to face four corners of the device hole 17. Further, the corners of the frame member 16 in FIG. 2 may be rounded at right angles, the right angles may be inclined, or the corners may be removed. In addition, the outer dimensions of the reinforcing plate 9 and the base film 1 do not necessarily have to match, for example, the base film can be made larger. Further, in the embodiment, the device hole of the reinforcing plate is larger than that of the base film, but the dimensions of both device holes may be approximately equal.

[0018]

As described in detail above, according to the semiconductor device of the present invention, since the heat-dissipating member is formed with the displacement preventing member, the displacement when the heat-dissipating plate is bonded to the reinforcing plate is prevented. I can do it.

[Brief description of the drawings]

FIG. 1 is a plan view and a sectional view showing a first embodiment of a semiconductor device according to the present invention.

FIG. 2 is a plan view and a sectional view showing a second embodiment of the semiconductor device according to the present invention.

FIG. 3 is a bottom view and a cross-sectional view showing the structure of a general tape BGA.

FIG. 4 is a cross-sectional view showing a state in which a heat conductive adhesive is applied to a reinforcing plate.

FIG. 5 is a cross-sectional view showing a state in which the heat sink is displaced from the reinforcing plate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base film 2 Wiring 3 Inner lead 4 Land 5 Semiconductor chip 6 Electrode 7 Resin 8 Solder bump 9 Reinforcement plate 10 Adhesive 11 Heat radiating plate 12 Heat conductive adhesive 13 Adhesive application nozzle 14 Depression 15 Projection 16 Frame member 17 Device Hall 18 adhesive

Claims (8)

(57) [Claims] 1. A base film having a device hole formed therein, a reinforcing plate having a device hole formed therein, and a heat sink, wherein one main surface of the base film and one main surface of the reinforcing plate are mutually opposed. A semiconductor device in which a device hole is fixed so as to communicate with each other, another main surface of the reinforcing plate is fixed to one main surface of the heat sink, and a semiconductor chip is further housed in the device hole; A semiconductor device, wherein a displacement preventing member that contacts a wall surface of the device hole is formed on the heat sink. 2. The semiconductor device according to claim 1, wherein the displacement prevention member contacts at least a corner of a wall surface of the device hole and a surface near the corner. 3. The semiconductor device according to claim 1, wherein the displacement prevention member is in contact with at least a corner of a wall surface of the device hole and a surface except the vicinity thereof. 4. The apparatus according to claim 1, wherein the displacement preventing member is obtained by deforming the heat sink itself.
4. The semiconductor device according to claim 3. 5. The semiconductor according to claim 1, wherein said misalignment preventing member comprises a member different from said heat radiating plate fixed to said heat radiating plate. apparatus. 6. The heat-dissipating member deforms the heat-dissipating plate such that portions of the heat-dissipating plate facing four corners of the wall of the device hole and portions in the vicinity thereof protrude toward the device hole. The semiconductor device according to claim 4, wherein the semiconductor device is formed. 7. The heat-dissipating member is formed by fixing a frame-shaped member having an outer size equal to or smaller than the size of an opening of the device hole on the heat-dissipating plate side to the heat-dissipating plate. 6. The semiconductor device according to 5. 8. The semiconductor device according to claim 7, wherein an outer size of the frame-shaped member is smaller than a size of the opening by a value corresponding to an allowable range of positional deviation.