JPH07201901A - Molding device for resin-sealing use - Google Patents

Abstract

PURPOSE:To form a resin-sealed part which has excellent moisture proofness and long-term high reliability with better production efficiency by preventing the residue of a bubble generated in cavity on the resin injecting gate side. CONSTITUTION:This is a molding device for resin-sealing use in which a lead frame 24 with a semiconductor element 23 mounted on is positioned, press- contacted and held by an upper mold 25 and a lower mold 25a. A molten resin S is injected to fill up a cavity 21 formed of the upper mold 25 and the lower mold 25a through a pressurized flow runner 26 and a resin injection gate 27 and the element 23 and the lead frame 24 are sealed with a resin in one end each. An air vent 29 for bubble discharging use is provided in at least area surface of the putting PL of the upper mold 25 or the lower mold 25a which is opposite to the position of a resin injecting gate 27 provided in the upper mold 25 or the lower mold 25a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-sealing die device for resin-sealing a lead frame on which a semiconductor element is mounted, and more specifically, a resin-sealing die having an air vent for air bubble discharge. Regarding the device.

[0002]

2. Description of the Related Art As shown in FIG. 3, a conventional resin sealing mold device of this type is a plurality of upper mold cavities 2.
An outer frame 24a of a lead frame 24 provided with an upper die chase block 22 in which 1a is embedded and a semiconductor element 23 is mounted.
Upper mold 25 pressed against the upper surface of the mold and a plurality of lower mold cavities 2
A lower die chase block 22a in which 1b is embedded, a runner 26 and a resin injection gate 27 that pressurize molten resin on the surface of the block 22a, and a lower die 25a that presses against the lower surface of the outer frame 24a of the lead frame 24 The lead frame 24 is configured to form a resin sealing portion.

When resin molding is performed using the resin molding die device 20 as described above, the upper mold 25 and the lower mold 25 are used.
A semiconductor element 23 is mounted between the lead frame 24 and the semiconductor device 23, and an electrode terminal (not shown) of the element 23 and a terminal lead 24b of the lead frame 24 are wire-bonded with a wire 24c to form an electric conduction circuit. Positioning pressure contact is clamped. Then, a molten resin having a predetermined pressure is injected into the cavity 21 formed by the cavity 21a of the upper mold 25 and the cavity 21b of the lower mold 25a from the resin injection gate 27 provided in the lower mold 25a, The molten resin is filled while the air (air) in the cavity 21 is gradually discharged from the air discharge air vent 28 provided on the opposite side of the gate. Then, the lead frame 24 having the resin sealing portion formed thereon is released after the injected resin is cured.
Collect.

[0004]

However, the injection gate 27 is provided on the putting surface of the upper mold 25 or the lower mold 25a, and one surface of the outer frame 24a of the lead frame 24 (the lower surface side in the embodiment of FIG. 3). It will be located so as to overlap. Therefore, the upper surface of the gate 27 is closed, and the resin injected from the gate 27 into the cavity 21 in this state flows as shown by the arrow in the figure and collides with the lead frame 24 in an oblique direction. Bubbles were generated due to the phenomenon that swirls occurred and the air (air) was wrapped up. As a result, the lead frame 24
The bubbles Q remain in the resin sealing portion 24c of the cavity 21 on the one surface side and the side where the gate 27 is located. If the air bubbles Q remain in the resin sealing portion 24c, the moisture resistance of the sealing portion 24c is reduced, which causes the intrusion of moisture, and there is a problem that the long-term reliability of the resin sealing portion 24c is reduced. It was

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and prevents a bubble Q generated in the cavity 21 on the gate 27 side from remaining and is a resin having excellent moisture resistance and long-term reliability. This is to form the sealing portion 24c with high production efficiency.

[0006]

According to a first aspect of the present invention, there is provided a resin molding die apparatus, wherein a lead frame on which a semiconductor element is mounted is clamped by an upper die and a lower die.
In the cavity formed by the upper mold and the lower mold, a molten resin is injected and filled through a runner and a resin injection gate, and a resin-sealing mold device for resin-sealing one end of the element and the lead frame, At least an air vent for discharging bubbles is provided on the surface of the putting area of the lower mold or the upper mold facing the position of the resin injection gate provided in the upper mold or the lower mold.

[0007]

In the resin sealing mold device according to the present invention, the air vent for discharging bubbles generated on the gate side wall surface in the cavity formed by the upper mold and the lower mold is used as the gate. Since the structure is provided on the facing PL surface of the upper mold or the lower mold, the bubbles generated in the cavity near the gate can be quickly discharged from the air vent to prevent the bubbles from remaining.

Furthermore, since the bubbles generated in the cavity are quickly discharged from the air vent, the injection speed of the resin can be increased as compared with the prior art. As a result, the production efficiency of resin encapsulation is significantly improved, and the curing speed of the injected resin in the cavity can be made uniform.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a sectional view of an essential part showing a mold clamping state of a resin sealing mold device according to the embodiment of the present invention. ,
FIG. 2 is a cross-sectional view of an essential part showing an outline of a sealing resin injection state according to the embodiment of the present invention.

As shown in FIGS. 1 and 2 (the same components as those in the conventional example are designated by the same reference numerals), a plurality of upper mold cavities 21 are provided in a resin sealing mold apparatus according to an embodiment of the present invention.
The chase block 22 having the embedded a is provided, and the upper die 25 is pressed against the upper surface of the outer frame 24a of the lead frame 24 on which the semiconductor element 23 is mounted, the chase block 22a having the plurality of upper die cavities 21b embedded therein, and The lower die 25a is in pressure contact with the lower surface of the outer frame 24a of the lead frame 24 provided with the runner 26 and the gate 27 for flowing the molten resin, and the upper die 25 is put in pressure contact with the upper surface of the outer frame 24a. An air vent 29 for discharging the generated bubbles Q is provided on the PL surface, and the resin sealing mold device 20 is shown in FIG.

When the lead frame 24 is resin-sealed using the resin-sealing die device, the upper mold 2 is used.
5 and the lower die 25a, the lead frame 24 is sandwiched by pressure contact, and the lead frame 24 is inserted into the cavity 21 formed by the upper die 25 and the lower die 25a.
The molten resin flows from the gate 27 at a predetermined pressure through the runner 26 provided on the lower mold 25a, which is pressed against the lower surface of the outer frame 24a, and the air in the cavity 21 is provided on the opposite side of the gate 27. The air-exhausting air vent 28 and the air bubbles Q remaining in the vicinity of the cavity 21 on the side of the gate 27 are gradually discharged from the air-venting air vent 29 of the air bubbles Q provided in the upper mold 25 to a putting escape portion (not shown). Are filled in the cavity 21 to form a sealing resin portion 24c. After that, the injected resin is cured and then released from the mold, and the lead frame 24, part of which is resin-sealed, is collected.

According to the above embodiment, the air and the air bubbles Q in the cavity 21 can be efficiently and completely discharged from the air vents 28, 29, so that the air bubbles Q may remain inside the resin sealing portion 24c. At the same time, after the bubbles Q are not left on the outer surface, the appearance quality can be improved.

Further, in the prior art, the resin filling speed is slowed down in order to prevent the generation of bubbles Q, but in the embodiment, the resin filling speed can be increased by providing the air vent 29 for discharging the bubbles Q. . Here, the air vent provided in the upper mold 25 is not limited to the position of the embodiment facing the position of the gate 27, but the upper mold 25 and the lower mold 25a may be formed depending on the inner volume of the cavity 21.
If a plurality of one or both putting PL surfaces are provided, the bubbles Q can be discharged more efficiently.

[0014]

According to the resin-sealing mold device of the present invention having the above-described structure, the bubbles generated during the injection of the molten resin can be quickly eliminated, so that the bubbles remain in the resin-sealing portion. It is possible to form a resin-sealed portion having excellent moisture resistance with high production efficiency.

Further, since the filling speed is improved, it is possible to prevent the occurrence of warpage of the resin-sealed portion even when the hardening speed of the sealing resin filled in the cavity is uniform.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts showing a mold clamped state of a resin sealing mold device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of an essential part showing an outline of a sealing resin injection state according to the embodiment of the present invention.

FIG. 3 is a cross-sectional view of essential parts showing a mold clamping state of a resin sealing mold device according to a conventional example.

[Explanation of symbols]

 20 Mold Equipment for Resin Encapsulation 21 Cavity 21a Upper Mold Cavity 21b Lower Mold Cavity 22 Upper Mold Chase Block 22a Lower Mold Chase Block 23 Semiconductor Element 24 Lead Frame 24a Outer Frame 24b Terminal Lead 24c Wire 25 Upper Mold 25a Lower Mold 26 Resin Pressure flow runner 27 Resin injection gate 28 Air vent for air discharge 29 Air vent for air vent PL Putting surface Q Air bubble S Molten resin

Claims (1)

[Claims] 1. A lead frame on which a semiconductor element is mounted is clamped by an upper die and a lower die, and a molten resin is injected and filled into a cavity formed by the upper die and the lower die through a runner and a resin injection gate. In the resin-sealing die device for resin-sealing one end of the element and the lead frame, at least the lower mold or the upper mold facing the position of the resin injection gate provided in the upper mold or the lower mold. A mold device for resin encapsulation, wherein an air vent for discharging bubbles is provided on the putting area surface.