JP2000058718A - Resin sealed semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent the peeling of a molding resin from a substrate by providing notched sections on the peripheral edge section of a substrate so as to make the molding resin flow in the notched section when the resin molded. SOLUTION: A BGA semiconductor device A has a package constituted by molding an IC chip 2 and bonding wires 3 with a thermosetting resin 5 on the upper surface of a nearly square film substrate 1. Since the resin 5 which flows and cures in notched sections 6 at the time of molding the resin 5 holds the substrate 1 in a wrapping state, the adhesion between the substrate 1 and resin 5 is improved and the peeling of the resin 5 from the substrate 1 can be prevented efficiently. Therefore, the peeling of the resin 5 from the substrate 1 from which the resin 5 easily peels can be prevented efficiently even when the number of notched sections 6 is small, because the resin 5 holds the substrate 1 by wrapping the corner sections of the substrate 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-sealed semiconductor device, and more particularly, to a package structure thereof.

[0002]

2. Description of the Related Art Conventionally, BG has been used as a resin-encapsulated semiconductor device.
An A-type semiconductor device is known. As shown in FIG. 4, such a BGA type semiconductor device X has an IC chip 20 mounted on a substrate 100.
0 is mounted and fixed, and the terminals of the IC chip 200 and the substrate 10
0 is connected to a conductive pattern (not shown) formed thereon by a bonding wire 300, and the IC chip 200 and the bonding wire 300 are molded with a thermosetting molding resin 400 to form a package. .

A solder bump 500 is formed on the back surface of the substrate 100. The solder bump 500 and the conduction pattern are
By conducting through a not-shown through hole, I
The C chip 200 and the solder bump 500 are conducted.

The substrate 100 is formed continuously on a lead frame. After being packaged as described above, the substrate 100 is cut off from the lead frame and made into a single product.

The substrate 100 is generally formed in a plate shape with glass epoxy resin or the like.
For mass production, a film made of a polypropylene resin or the like is often used.

[0006]

However, in the package structure of the conventional BGA type semiconductor device X described above, since the molding resin 400 is molded only on the upper surface of the substrate 100 as shown in the figure, Insufficient welding to the surface causes molding resin 40
0 has a disadvantage that it is easily peeled from the substrate 100.

That is, the substrate 100 and the molding resin 400
Because of the different materials, the coefficient of thermal expansion is different, warpage occurs during molding, the adhesion between the substrate 100 and the molding resin 400 is reduced, and the warpage is similarly caused during mounting and reflow of the BGA type semiconductor device X. It is easy to peel off. This tendency is particularly remarkable when the substrate 100 is a film.

[0008] When such peeling occurs, moisture is absorbed from the bonding surface and causes package cracking at the time of mounting or reflowing the BGA type semiconductor device X. Therefore, preventing peeling of the molding resin 400 is a major problem.

An object of the present invention is to provide a resin-sealed semiconductor device which can solve the above-mentioned problems.

[0010]

Therefore, in order to solve the above-mentioned problems, according to the present invention, in accordance with the present invention, I
In a resin-encapsulated semiconductor device in which a C chip is fixed, wire-bonded, and resin-molded, a notch portion through which molding resin flows during resin molding is provided on the peripheral side of the substrate. Therefore, the mold resin that has flowed into the cutout portion and hardened is held so as to enclose the substrate, and peeling of the mold portion can be prevented.

Further, in the present invention, the notch is provided at a position on the substrate which avoids the conduction pattern.

Further, in the present invention, a plurality of the notches are provided in a peripheral portion of the substrate.

Further, according to the present invention, the notches are provided at least at four corners of the substrate.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to a resin-encapsulated semiconductor device in which an IC chip is fixed on the upper surface of a substrate, wire-bonded, and resin-molded, and a molding resin flows into a peripheral portion of the substrate during resin molding. It is provided with a notch portion to be made.

That is, a notch is provided in advance on the peripheral side of the substrate, the molding resin flows into the notch at the time of molding, and the molding resin reaches the lower surface of the substrate. The mold resin is held so as to enclose the substrate to improve the adhesion, thereby preventing the mold resin from separating from the substrate.

The location where the notch is provided is a location where a conductive pattern formed on the substrate is avoided so as not to hinder the function of the semiconductor device, and the location may be, for example, the periphery of the substrate. .

Although the number of cutouts is not particularly limited, one cutout may be provided on each side of the board or at each of the four corners of the board.

In particular, when provided at the four corners, the separation of the substrate and the molding resin can be efficiently prevented with a small number.

Also, a plurality of notches can be provided on each side of the substrate for molding, and the holding force of the substrate by the molding resin can be increased to further improve the adhesion.

As described above, according to the present invention, the adhesion between the molding resin and the substrate is improved, and the peeling of the molding resin from the substrate can be effectively prevented.

In particular, when the substrate is made of a thin film, the effect becomes great. The film is used as a substrate, and the molding resin, which is a drawback of such a film substrate, is prevented from being peeled off to prevent defective products. By suppressing as much as possible, mass production of a thin and high-quality BGA type semiconductor device can be realized.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings.

(First Embodiment) FIG. 1 is a bottom view of a BGA type semiconductor device A as a resin-sealed type semiconductor device according to a first embodiment, and FIG. 2 is a cross-sectional view taken along line II of FIG. .

As shown in FIG. 2, a BGA type semiconductor device A
The IC chip 2 is fixed to the upper surface of a substantially square film substrate 1 made of a film made of resin such as polypropylene, and is wire-bonded to a conductive pattern (not shown) formed on the film substrate 1.

Reference numeral 3 denotes a bonding wire.

On the back surface of the film substrate 1, solder bumps 4
Are provided in a matrix shape, and the solder bumps 4 and the conductive patterns are electrically connected through through holes (not shown).

The IC chip 2 and the bonding wires 3 are molded with a thermosetting resin 5 to form a package.

In the BGA type semiconductor device A having such a structure, the gist of the present invention is that a notch 6 into which a thermosetting resin 5 as a molding resin flows is provided on the peripheral side of the film substrate 1. It is in.

That is, since the thermosetting resin 5 and the film substrate 1 have different coefficients of thermal expansion due to the difference in their materials,
The package itself is warped at the time of resin molding, at the time of reflow of the solder bumps 4 in a later process, or at the time of mounting the BGA type semiconductor device A, so that the film substrate 1 and the thermosetting resin 5 are easily separated. However, with the above-described configuration, the thermosetting resin 5 flows into the cutout portion 6 at the time of molding and is hardened, and the thermosetting resin 5 is held so as to enclose the film substrate 1. The adhesiveness between the thermosetting resin 1 and the thermosetting resin 5 is improved, and the peeling of the two can be efficiently prevented.

In this embodiment, as shown in FIG. 1, the notches 6 are formed at the four corners of the film substrate 1 so as to avoid the conductive patterns (not shown).

Therefore, since the thermosetting resin 5 wraps and holds each corner of the film substrate 1 from which the thermosetting resin 5 is easily peeled, even if the number of the cutouts 6 is small, the peeling can be efficiently prevented. Becomes

Notches 6 provided at four corners of film substrate 1
May be formed for each film substrate 1, but if the film substrate 1 is formed in a matrix on a large-sized aggregate substrate film in which many film substrates 1 are aggregated, the notch 6 is formed in each film substrate 1.
Can be efficiently formed by the four corners.

The shape of the notch 6 is not limited to a pentagon as shown in FIG. 1, but may be any shape.

(Second Embodiment) FIG. 3 shows a B according to a second embodiment.
The bottom view of GA type semiconductor device A is shown. The reference numerals used in this embodiment are the same as those in the first embodiment for the same components.

As shown, in this embodiment, the notch 6
Are formed on the periphery of the film substrate 1.

The cutouts 6 are provided at the four corners where the thermosetting resin 5 is most likely to be peeled off and on each side, and the cutouts 6 can have any shape. A circular shape is formed, and a semi-circular shape is formed on each side.
The number of the cutouts 6 provided on each side may be singular or plural. In the present embodiment, a plurality of cutouts 6 are provided at regular intervals. The other configuration is the same as that of the first embodiment, and the description is omitted here.

With the above-described structure, in the present embodiment, the holding force of the film substrate 1 by the thermosetting resin 5 is larger than in the package structure of the first embodiment, and the adhesion is further increased and the film substrate 1 is peeled off. Can be reliably prevented.

[0038]

The present invention is embodied in the above-described embodiment, and has the following effects.

According to the first aspect of the present invention, in a resin-sealed semiconductor device in which an IC chip is fixed to the upper surface of a substrate, wire-bonded, and resin-molded, a molding resin is applied to a peripheral portion of the substrate during resin molding. By providing the cut-out portion to be flown, the mold resin flowing into the cut-out portion and being hardened is held so as to enclose the substrate, and peeling of the mold portion can be prevented.

According to the second aspect of the present invention, the function of the resin-encapsulated semiconductor device is not hindered by providing the notch at a position avoiding the conductive pattern on the substrate.

According to the third aspect of the present invention, by providing a plurality of the notches in the peripheral portion of the substrate, the holding force of the substrate by the molding resin is increased, and the adhesion is further improved. Can be prevented more reliably.

According to the fourth aspect of the present invention, since the notches are provided at least at the four corners of the substrate, the separation of the substrate and the molding resin can be efficiently prevented with a small number.

[Brief description of the drawings]

FIG. 1 is a bottom view of a BGA type semiconductor device according to a first embodiment.

FIG. 2 is a cross-sectional view taken along line II of FIG.

FIG. 3 is a bottom view of a BGA type semiconductor device according to a second embodiment.

FIG. 4 is an explanatory view showing a package structure of a conventional BGA type semiconductor device.

[Explanation of symbols]

 A BGA type semiconductor device (resin-sealed type semiconductor device) 1 film substrate (substrate) 2 IC chip 3 bonding wire 4 solder bump 5 thermosetting resin (resin for molding) 6 notch

Claims (4)

[Claims] 1. A resin-encapsulated semiconductor device in which an IC chip is fixed to an upper surface of a substrate, wire-bonded, and resin-molded, a notch portion for allowing a molding resin to flow during resin molding is provided in a peripheral portion of the substrate. A resin-encapsulated semiconductor device, comprising: 2. The resin-encapsulated semiconductor device according to claim 1, wherein the notch is provided at a position avoiding the conductive pattern on the substrate. 3. The resin-encapsulated semiconductor device according to claim 1, wherein a plurality of cutouts are provided in a peripheral portion of the substrate. 4. The resin-sealed semiconductor device according to claim 1, wherein the notches are provided at least at four corners of the substrate.