JP2001250837A - Resin sealing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin sealing method which can improve the productivity without producing any damage or resin contamination on a terminal joint, when sealing an opening recessed part formed on a circuit board. SOLUTION: A protection member 6 in which a window 6a corresponding to an opening recessed part 2 of a circuit board 1 is formed around the opening recessed part 2 thereof is overlapped, and the circuit board 1 is clamped together with the member 6 by a mold die 5 so as to form a resin gate on the member 6. A sealing resin 11 is press-fed through the resin gate to seal the opening recessed part 6 by resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a semiconductor device mounted on an opening recess formed in a circuit board by being electrically connected to a wiring pattern on the circuit board side. The present invention relates to a resin sealing method for sealing a concave portion of an opening of a circuit board on which a bonding portion to be exposed and connected to an external connection terminal is formed.

[0002]

2. Description of the Related Art As an example of a semiconductor device, a BGA (Ba
(II Grid Array) type semiconductor devices have been put into practical use. As a method of manufacturing the BGA type semiconductor device, for example, a manufacturing process disclosed in Japanese Patent Application Laid-Open No. 10-199899 has been proposed. In this method of manufacturing a semiconductor device, as shown in FIG. 16, a pressing process is performed on a semiconductor element mounting portion of a metal substrate 51 to form an element mounting portion 52 in a concave shape. An opening 53 corresponding to the element mounting portion 52 is provided.
Is formed, and a circuit board 55 having a wiring pattern 54 around the opening 53 is formed. Then, the metal substrate 51
The opening 53 of the circuit board 55 is aligned with the element mounting portion 52 of the above, and these are thermocompression-bonded via the prepreg layer 56. Next, a part of the wiring pattern 54 is exposed as a land part 57 to which an external connection terminal is bonded, and is covered with a solder resist film 58 to form a semiconductor element mounting substrate 59. Next, the semiconductor element 60 is mounted on the element mounting part 52, and the terminal part of the semiconductor element 60 and the terminal part of the wiring pattern 54 are electrically connected by the bonding wire 61. Then, the sealing resin 62 is poured into the element mounting portion 52 by a potting molding method, and the opening portion 53 is resin-sealed to form a package portion. Next, after solder balls 63 are placed on the land portions 57 and reflowed to form solder bumps, the semiconductor devices are separated into individual pieces by dicing at the cutting lines 64 to form semiconductor devices.

[0003]

However, when the package is formed by the potting molding method,
It takes a long time to fill and cure the sealing resin 62, and the productivity is low. In addition, since no resin pressure is applied, the package portion is likely to be non-uniform and the molding quality is reduced. The land 57
Resin contamination may occur, and in this case, the bonding of the solder balls 63 may be defective. Also, if the package part is formed by a transfer molding method,
Since the mold for clamping the semiconductor element mounting substrate 59 needs to form a gate runner on the land 57 or form an air vent to seal the resin, the land 57 is damaged by the mold gate. It is not generally used because it easily causes resin stains.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to improve productivity without causing scratches or resin stains on terminal joints when resin-sealing an opening recess formed in a circuit board. An object of the present invention is to provide an improved resin sealing method.

[0005]

To solve the above-mentioned problems, the present invention has the following arrangement. That is, the semiconductor element is mounted in the opening recess formed in the circuit board while being electrically connected to the wiring pattern on the circuit board side, and the external connection terminal is exposed around the opening recess and exposed from the protective film layer. In a resin sealing method for resin-sealing an opening concave portion of a circuit board formed with a joint portion, a protection member having a window corresponding to the opening concave portion is superimposed around the opening concave portion of the circuit board, and The circuit board is clamped together with the protection member by a mold, and the sealing resin is pressure-fed through a resin path formed on the protection member to seal the opening concave portion with the resin.

Further, a heat-resistant masking tape may be used as a protective member, and the heat-resistant masking tape may be bonded to a protective film layer of a circuit board before resin sealing.
Alternatively, the release film may be suction-held and held on the clamp surface on the side of the opening concave portion of the molding die and then sealed with a resin. In addition, the circuit board may be formed by bonding a metal plate to a resin substrate having a through-hole capable of accommodating a semiconductor element and forming an opening recess. Alternatively, the release film may be sucked and held on the upper and lower clamp surfaces of the molding die and sealed with a resin. Further, a protection plate may be used as a protection member, and the protection plate may be superimposed on the protection film layer of the circuit board before resin sealing.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the resin sealing method according to the present invention will be described below in detail with reference to the accompanying drawings. [First Embodiment] FIG. 1 is an explanatory view showing a circuit board after resin sealing, FIG. 2 is a cross-sectional explanatory view of a mold in a resin sealing step, and FIG. 3 shows a gate position of the mold in FIG. FIG. 4 is an explanatory view showing a gate position and an air vent position in the mold shown in FIG.

Referring to FIG. 1, a circuit board sealed with resin in this embodiment will be described. Reference numeral 1 denotes a circuit board on which a wiring pattern is formed, and an insulating resin substrate such as a glass epoxy resin substrate is used. The circuit board 1 may be a single-layer or multi-layer circuit board. An opening recess 2 is formed in the circuit board 1. The bottom of the opening concave portion 2 is used as a semiconductor element mounting portion 3. A semiconductor element 4 is mounted on the element mounting section 3 and is electrically connected to a wiring pattern on the circuit board side by bonding wires or the like. Around the opening concave portion 2 of the circuit board 1, a joint (land portion) to which an external connection terminal connected to the wiring pattern is joined is formed to be exposed from the protective film layer (solder resist layer).

The circuit board 1 is carried into a mold 5 provided in a known transfer molding apparatus and sealed with a resin.
First, as shown in FIG. 1, a protective member (such as a heat-resistant masking tape) 6 is adhered to the periphery of the opening concave portion 2 of the circuit board 1. The protection member 6 has a window 6 a corresponding to the opening recess 2.
Are formed. An arbitrary material such as an epoxy resin material is used for the material of the protection member 6. When the protective member 6 is bonded, it is preferable that the protective member 6 is bonded only to the protective film layer via an adhesive.

In FIG. 2, a molding die 5 includes an upper die 7
And a lower mold 8, and a cavity recess 9 for housing the circuit board 1 is formed on the lower mold 8 side. In FIG. 3, a mold runner gate 10 communicating with a pot (not shown) is formed in the upper mold 7. The circuit board 1 to which the protection member 6 is adhered is clamped by the mold 5, and the sealing resin 11 is pressure-fed from the pot via the mold runner gate 10 formed on the protection member 6, and the opening concave portion 2 is made of resin. Seal. FIG. 4 shows an arrangement example of the mold runner gate 10 and the air vent groove 12 formed in the mold 5. Since the periphery of the opening concave portion 2 is covered with the protective member 6, the mold runner gate 10 and the air vent groove 12 can be formed at arbitrary positions of the upper mold 7, so that the degree of freedom of the mold design is increased.

After resin sealing, the circuit board 1 is taken out of the mold 5 and unnecessary resin such as a runner gate of a molded product is separated. Then, the protective member 6 is peeled off, and the solder balls 13 are mounted on the exposed joints. And reflow to join. In this embodiment, the case where the semiconductor device pieces are sealed with resin is described. However, the circuit board 1 may be sealed with resin in a state where a plurality of semiconductor devices are connected or arranged in a matrix. In this case, the semiconductor device is manufactured by dicing the circuit board 1 after resin sealing and separating it into individual pieces.

According to the above resin sealing method, the protection member 6 is bonded to the protection film layer formed around the opening recess 2 of the circuit board 1, and the mold runner gate 10 formed on the protection member 6 is bonded. When the circuit board 1 is clamped by the mold 5, the sealing portion 11 can be damaged or stained by the mold gate when the circuit board 1 is clamped. In addition, the bondability of the solder balls 13 does not decrease. Also, the mold runner gate 10
The air vent groove 12 and the air vent groove 12 can also be formed at arbitrary positions on the mold 5, thereby increasing the degree of freedom in mold design. Further, since the circuit board 1 can be resin-sealed by the transfer molding method, productivity can be improved.

Second Embodiment Next, another example of the resin sealing method according to the first embodiment will be described with reference to FIGS. FIG. 5 is a cross-sectional explanatory view of the mold in the resin sealing step, and FIG. 6 is a cross-sectional explanatory view including the gate position of the mold in FIG. The same members as those in the first embodiment are denoted by the same reference numerals, and the description is referred to. In FIG. 5, a release film 14 is held by suction on a clamp surface on the upper mold 7 side (opening recess 2 side) of the mold 5. The release film 14 may be either a long shape or a strip shape, and is desirably sucked by a suction mechanism (not shown) so as to cover at least the resin path in the mold surface. The release film 14 has heat resistance enough to withstand the heating temperature of the mold 5 and is easily peeled from the mold surface, and is a film material having flexibility and extensibility, for example, PTFE, ETFE. , PET, F
EP, fluorine impregnated glass cloth, polypropylene, polyvinylidene chloride and the like are preferably used. In this embodiment, the release film 14 may be provided on the lower mold 9 including the cavity recess 9. Thereby, the releasability of the molded product from the mold surface can be improved.

Third Embodiment Next, another example of the resin sealing method will be described with reference to FIGS. 7 is an explanatory view showing a circuit board after resin sealing, FIG. 8 is a sectional explanatory view of a mold in a resin sealing step, and FIG. 9 is a sectional explanatory view including a gate position of the mold in FIG. . The same members as those in the first embodiment are denoted by the same reference numerals, and the description is referred to.

The configuration of the circuit board used in the resin sealing method of this embodiment will be described. In FIG. 7, through holes are formed in a circuit board 1 such as a glass epoxy resin substrate (for example, having a thickness of 0.65 mm) by pressing. On one substrate surface of the circuit board 1, a protective film layer (solder resist layer) is formed on a wiring pattern, and a part of the wiring pattern is exposed and formed as a joint (land). On the other surface of the circuit board 1, a metal plate such as a copper plate (for example, having a thickness of 0.25 m
The heat sink 15 made of m) is bonded to form the opening concave portion 2. The bottom of the opening recess 2 is
Is used as the semiconductor element mounting portion 3 for mounting the semiconductor device.

The circuit board 1 is carried into a mold 17 provided in a known transfer molding apparatus and sealed with a resin. As shown in FIG. 7, a protection member (such as a heat-resistant masking tape) 6 is adhered to the periphery of the opening recess 2 of the circuit board 1. When the protective member 6 is bonded, it is preferable that the protective member 6 is bonded only to the protective film layer via an adhesive.

In FIG. 8, a mold 17 includes an upper mold 18 and a lower mold 19, and a cavity recess 20 for accommodating the circuit board 1 is formed on the upper mold 18 side. Further, in FIG. 9, a mold runner gate 22 communicating with a pot (not shown) is formed in the upper mold 18. FIG.
Then, the circuit board 1 is clamped by the mold 18 and the sealing resin 11 is pressure-fed from the pot via the mold runner gate 22 formed on the protection member 6 to seal the opening recess 2 with resin. Also in the present embodiment, the mold runner gate 22 and the air vent groove (not shown) are provided in the mold 18.
Can be formed at any position.

[Fourth Embodiment] Next, another example of the resin sealing method according to the third embodiment will be described with reference to FIGS. FIG. 10 is an explanatory cross-sectional view of a mold in a resin sealing step, and FIG. 11 is an explanatory cross-sectional view including a gate position of the mold in FIG. The same members as those in the third embodiment are denoted by the same reference numerals, and the description is referred to. In FIG. 10, the clamp surface including the cavity recess 20 on the upper mold 18 side (opening recess 2 side) of the molding die 17 includes:
The release film 14 is held by suction. The release film 14 may be either a long shape or a strip shape, and is desirably sucked by a suction mechanism (not shown) so as to cover at least the resin path in the mold surface. FIG.
As shown in FIG. 1, the circuit board 1 is clamped by a mold 18 and the mold runner gate 2 formed on the protection member 6 is formed.
The sealing resin 11 is pressure-fed from the pot through the opening 2 to seal the opening recess 2 with resin. Thereby, the releasability of the molded product from the mold surface can be improved.

Fifth Embodiment Next, still another example of the resin sealing method according to the third embodiment will be described with reference to FIGS. FIG. 12 is a cross-sectional explanatory view of a mold in a resin sealing step, and FIG. 13 is a cross-sectional explanatory view including a gate position of the mold in FIG. The same members as those in the third embodiment are denoted by the same reference numerals, and the description is referred to. 12 and 13, the release film 14 may be suction-held on the upper and lower clamp surfaces of the mold 17 and sealed with a resin. In this case, the protective member 6 attached to the circuit board 1 is unnecessary at the gate position because of the release film 14, and can be omitted.

Sixth Embodiment Next, still another example of the resin sealing method will be described with reference to FIG. FIG. 14 is an explanatory sectional view including the gate position of the mold. The same members as those in the first embodiment are denoted by the same reference numerals, and the description is referred to. A wiring pattern is formed on the circuit board 1, and an insulating resin substrate such as a glass epoxy resin substrate is used. The circuit board 1 may be a single-layer or multi-layer circuit board. A heat sink 24 such as a copper plate is adhered to the circuit board 1 to form the opening concave portion 2. The bottom of the opening concave portion 2 is used as a semiconductor element mounting portion 3. A semiconductor element 4 is mounted on the element mounting section 3 and is electrically connected to a wiring pattern on the circuit board side by bonding wires or the like. Around the opening concave portion 2 of the circuit board 1, a joint (land portion) to which an external connection terminal connected to the wiring pattern is joined is formed to be exposed from the protective film layer (solder resist layer).

The circuit board 1 is loaded into a mold 27 provided in a known transfer molding apparatus and sealed with a resin. A protective plate 26 having a window 26a corresponding to the opening 2 is positioned and overlaid on a protective film layer formed around the opening 2 of the circuit board 1. The plate thickness of the protection plate 26 is, for example, about 0.1 mm, and the material is preferably a heat-resistant resin material, a resin-releasing metal plate, or the like.

Referring to FIG. 14, a mold 27 includes an upper mold 28 and a lower mold 29, and a cavity recess 30 for accommodating the circuit board 1 is formed on the lower mold 29 side.
A mold runner gate 31 communicating with a pot (not shown) is formed in the upper mold 28. The circuit board 1 is clamped by a mold 27 and the sealing resin 11 is pressure-fed from a pot via a mold runner gate 10 formed on the protection plate 26 to seal the opening recess 2 with resin. In this case, since the periphery of the opening concave portion 2 is covered with the protection plate 26,
There is no damage or dirt on the joint, and the mold runner gate 31 and the air vent groove (not shown) can be formed at arbitrary positions of the mold 27, so that the degree of freedom in mold design is increased. Further, since the protection plate 26 is not adhered to the substrate surface, it can be easily attached to and detached from the circuit board 1.

Seventh Embodiment Next, still another example of the resin sealing method according to the sixth embodiment will be described with reference to FIG. FIG. 15 is an explanatory sectional view including the gate position of the mold. The same members as those in the sixth embodiment are denoted by the same reference numerals, and the description is referred to. In the sixth embodiment, the protection plate 26 is superposed on the substrate surface on which the joint is formed. However, the protection plate 26 may be bonded to the protection film layer of the circuit board 1 via an adhesive. The protection plate 26 has a larger size than the circuit board 1 in consideration of the peelability. When the protection plate 26 is bonded, it is preferable that the protection plate 26 is bonded to only the protection film layer via an adhesive. Further, the protection plate 26 may be simply placed on the circuit board 1. As shown in FIG. 15, the circuit board 1 is clamped by the mold 27 and the sealing resin 11 is inserted through the mold runner gate 31 formed on the protection plate 26.
Is pressure-fed from the pot to seal the opening recess 2 with resin. At this time, the releasability can be improved by providing the protection plate 26 on the mold runner gate 31 side widely on the mold runner gate 31 side.

Although various preferred embodiments of the present invention have been described, the present invention is not limited to the above-described embodiments. For example, the material and size of the protection member 6 and the protection plate 26 are arbitrary. Of course, many modifications can be made without departing from the spirit of the invention.

[0025]

According to the resin sealing method of the present invention,
Overlay the protective member around the opening recess of the circuit board,
Since the sealing resin can be sealed by pressing the sealing resin through the mold runner gate formed on the protection member, when the circuit board is clamped by the mold, the terminal joint is formed by the mold gate. There is no damage and no dirt, and there is no decrease in solder ball bonding. In addition, since the mold runner gate and the air vent groove can be formed at any positions of the mold, the degree of freedom in mold design is increased. Further, since the circuit board can be sealed with a resin by a transfer molding method, productivity can be improved.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a circuit board after resin sealing according to a first embodiment.

FIG. 2 is an explanatory sectional view of a mold in a resin sealing step.

FIG. 3 is an explanatory sectional view including a gate position of the mold shown in FIG. 2;

FIG. 4 is an explanatory view showing a gate position and an air vent position in the mold shown in FIG. 2;

FIG. 5 is an explanatory sectional view of a molding die in a resin sealing step according to a second embodiment.

6 is an explanatory sectional view including a gate position of the mold shown in FIG. 5;

FIG. 7 is an explanatory view showing a circuit board after resin sealing according to a third embodiment.

FIG. 8 is an explanatory sectional view of a mold in a resin sealing step.

9 is an explanatory sectional view including a gate position of the mold shown in FIG. 8;

FIG. 10 is an explanatory sectional view of a molding die in a resin sealing step according to a fourth embodiment.

11 is an explanatory cross-sectional view including a gate position of the mold shown in FIG. 10;

FIG. 12 is an explanatory sectional view of a molding die in a resin sealing step according to a fifth embodiment.

13 is an explanatory sectional view including a gate position of the mold shown in FIG. 10;

FIG. 14 is an explanatory cross-sectional view including a gate position of a mold according to a sixth embodiment.

FIG. 15 is an explanatory sectional view including a gate position of a mold according to a seventh embodiment.

FIG. 16 is an explanatory view showing a conventional method for manufacturing a semiconductor device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Circuit board 2 Opening recess 3 Semiconductor element mounting part 4 Semiconductor element 5, 17, 27 Mold 6 Protective member 6a, 26a Window 7, 18, 28 Upper die 8, 19, 29 Lower die 9, 20, 30 Cavity concave 10, 22, 31 Mold runner gate 11 Sealing resin 12 Air vent groove 13 Solder ball 14 Release film 15, 24 Heat sink 26 Protection plate

Claims (6)

[Claims] A semiconductor element is mounted in an opening recess formed in a circuit board while being electrically connected to a wiring pattern on the circuit board side, and an external connection terminal is exposed around the opening recess from a protective film layer. In a resin sealing method for resin-sealing an opening recess of the circuit board formed with a joint portion to be joined, a protection corresponding to a window corresponding to the opening recess is formed around the opening recess of the circuit board. By overlapping the members, clamping the circuit board together with the protection member with a molding die, and forcing the sealing resin through a resin path formed on the protection member to seal the opening concave portion with the resin. Characteristic resin sealing method. 2. The resin according to claim 1, wherein a heat-resistant masking tape is used as the protective member, and the heat-resistant masking tape is adhered to a protective film layer of the circuit board before resin sealing. Sealing method. 3. The resin sealing method according to claim 1, wherein the molding die seals the resin by sucking and holding a release film on a clamp surface of the circuit board on the side of the opening concave portion. . 4. The circuit board according to claim 1, wherein the opening is formed by bonding a metal plate to a resin substrate having a through-hole capable of accommodating the semiconductor element. Or the resin sealing method according to 3. 5. An upper and lower clamp surface of the mold,
The resin sealing method according to claim 4, wherein the resin is sealed by holding the release film by suction. 6. The resin sealing method according to claim 1, wherein a protective plate is used as the protective member, and the protective plate is overlapped with a protective film layer of the circuit board before resin sealing.