JPH08227960A - Lead frame for semiconductor device - Google Patents

Abstract

PURPOSE: To prevent breakdown of a molding die and generation of lead dent, to eliminate a cutting die, to reduce the number of cutting processes, to prevent deterioration of accuracy of a semiconductor device, contact failure and installa tion breakdown by readily preventing resin burr from remaining without using a cutting die. CONSTITUTION: A slit 5 is provided along an outer circumference of an area near a gate part 11, especially, a gate part cut-out hole 3. Thereby, while sealing resin 10 of the gate part 11 and a runner 9 can be removed during gate break after sealing by sealing resin 10, a part of a lead frame 1 thereabout can be readily removed simultaneously. Therefore, it is possible to prevent resin burr from remaining in a side surface of the gate part cut-out hole 3 after gate break.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art FIGS. 5 (a) and 5 (b) are plan views of an example of a conventional semiconductor device lead frame (hereinafter referred to as a lead frame) after resin encapsulation and a state of being clamped by a sealing die. 6 is a sectional view taken along line EE ′ in FIG. FIG. 5 (a),
As shown in (b), the sealing resin 10 is filled from the runner 9 through the gate portion 11 into the resin mold package 2 to seal the semiconductor element. After that, the encapsulating resin 10 is cured and molded, and then taken out from the encapsulating molds (upper mold) 7 and (lower mold) 8, and is molded from the resin mold package 2 to the gate portion 11 and the gate part 11 so as to be easily processed in a later step. The sealing resin 10 at the runner 9 is separated.

FIGS. 6 (a) and 6 (b) are plan views of a conventional lead frame after a gate break and its FF '.
It is a line sectional view. As shown in FIGS. 6A and 6B, in the conventional lead frame, when the sealing resin 10 in the gate portion 11 and the runner 9 is separated, a resin burr is always formed on the inner surface of the gate portion cutout hole 3. 12 remained attached. This resin burr 12 may fall off in the molding process of the outer lead 4 or the exterior plating process in a later process. Due to the resin burr 12 dropping in the subsequent process, the mold is damaged or the outer lead 4 is broken once every 200 shots. There was a problem that the outer lead 4 was deformed by producing dents at a rate of occurrence of 0.2% during the machining.

In this conventional technique, it is necessary to partially cut and remove the lead frame 1 in the vicinity of the resin burr 12 in order to remove the resin burr 12, so that the man-hours are increased and the necessary equipment is increased. I had problems such as. Also,
In a later step, the resin burr 12 is attached to the lead frame 1 in the vicinity thereof.
There is also a method of cutting and removing the whole part, but at that time, an unnecessary external force is applied to the resin-sealed semiconductor element and the lead frame 1, and the hanging pin provided in the gate part 11 is cut at an occurrence rate of 80% or more, Accuracy deterioration due to transportation, occurrence rate 0.
There were many problems such as 3% of contact mistakes and equipment damage of once / 200 shots.

In order to prevent the above-mentioned resin burrs 12 from remaining adhered, in JP-A-58-207660, a hole or a notch is provided in the portion of the frame portion of the lead frame facing the resin injection port of the mold. However, in this lead frame, resin adheres to the inner surface of the hole or notch and resin burrs adhere and remain, which is not a sufficient countermeasure.

[0006]

As described above,
In this conventional lead frame, the resin burr adheres to and remains on the inner surface of the notch hole in the gate portion and drops off. Therefore, there are problems listed below.

(1) Outer lead processing Inducing defects such as damage to the die or deformation of the outer leads.

(2) It is necessary to increase man-hours and add equipment.

(3) Defects such as deterioration of accuracy, contact mistake, equipment damage, etc. occur.

It is an object of the present invention to provide a lead frame for a semiconductor device which is free from damage to molds and equipment, increase in man-hours, equipment addition, deterioration in accuracy and contact errors.

[0011]

According to a first aspect of the present invention, a gate is provided at a position intersecting with the gate for dissolving resin inflow provided in an encapsulating mold for injecting and molding a dissolving resin to seal a semiconductor element. In a resin-sealed semiconductor device lead frame having a partial cutout hole, a slit is provided along the periphery in the vicinity of the outside of the gate cutout hole.

According to a second aspect of the present invention, a gate portion cutout hole is provided at a position intersecting with the melted resin inflow gate provided in an encapsulating mold for injecting and molding a melted resin to seal a semiconductor element. A resin-encapsulated lead frame for a semiconductor device is characterized in that a half-etch is provided along the periphery in the vicinity of the outside of the gate portion cutout hole.

Further, in the first invention or the second invention, the slit or the slit is formed so that the melted resin covers a region surrounded by the outer circumference of the gate cutout hole and the inner circumference of the slit or half etch. It is characterized by forming a half etch.

[0014]

Embodiments of the present invention will now be described with reference to the drawings.

1 (a) and 1 (b) are a plan view after resin sealing of a first embodiment of the present invention and a cross-sectional view taken along the line AA 'in a state of being clamped by a sealing mold. . In the first embodiment of the present invention, as shown in FIGS. 1 (a) and 1 (b), the molten resin provided in the encapsulating molds 7 and 8 for injecting and molding the molten resin to seal the semiconductor element. Upper and lower gate portion cutout holes 3 are provided at positions intersecting the inflow gate portion 11,
Slits 5 are provided along the periphery in the vicinity of the outside.

With the lead frame 1 having such a structure, the gate portion 1 is sealed with the sealing resin 10 after resin sealing.
1 and the sealing resin 10 of the runner 9 are removed at the time of the gate break. At that time, the portion of the lead frame 1 around the upper and lower gate portion cutout holes 3 is cut and removed along the slits 5, and the upper and lower gate portion cutout holes 3 are removed. 3. The sealing resin 10 attached and remaining on the inner wall surface of 3 is simultaneously removed.

2 (a) and 2 (b) are a plan view and a cross section taken along the line BB 'of FIG. 2 after the gate break of the first embodiment of the present invention. As shown in FIGS. 2A and 2B, after the gate break, in the first embodiment, the sealing resin 10 remaining on the inner wall of the gate cutout hole 3 is completely removed. The step of removing 12 is unnecessary, and
Equipment for cutting and removing the periphery of the gate cutout hole 3 is also unnecessary.

FIGS. 3 (a) and 3 (b) are a plan view after resin sealing and a sectional view taken along the line CC 'in the state of being clamped by an encapsulating mold according to the second embodiment of the present invention. . In the second embodiment of the present invention, as shown in FIGS. 3A and 3B, a half etch 6 is provided along the periphery of the gate notch 3 instead of the slit 5 of the first embodiment. The effect is the first in the example
Is the same as the embodiment described above.

FIGS. 4 (a) and 4 (b) are a plan view of the third embodiment of the present invention after resin encapsulation and a sectional view taken along the line DD 'in a state of being clamped by an enclosing mold. In the third embodiment of the present invention, as shown in FIGS. 4A and 4B, in the first embodiment and the second embodiment, the molten resin is the gate portion 1
The slit 5 or the half etch 6 is formed in the lead frame 1 so that the sealing resin 10 cured in 1 covers the region surrounded by the outer periphery of the gate cutout hole 3 and the inner periphery of the slit 5 or the half etch 6.

By constructing the lead frame 1 in this way, the sealing resin 10 of the gate portion 11 is formed in a region surrounded by the outer periphery of the gate portion cutout hole 3 and the slit 5 or the half etch 6 with the lead frame 1. Adhesion is further improved, and when the sealing resin 10 of the gate portion 11 and the runner 9 is removed at the time of the gate break, from the slit 5 or the half-etch 6 portion of the lead frame 1 in the vicinity of the gate cutout hole 3. The cutting and removal can be effectively performed, and the working effects superior to those of the first and second embodiments can be obtained.

Although the case of the upper and lower gates has been described above, the present invention can be applied to the case of the lower gate.

[0022]

As described above, according to the present invention, a slit or a half-etch is provided along the outer periphery of the notch hole of the gate portion, and further, a lead frame in the outer periphery of the gate portion and an inner periphery of the slit or the half-etch is formed. By increasing the adhesion with the encapsulation resin, the lead frame near the gate cutout hole is cut and removed at the same time as the removal of the encapsulation resin on the gate and runners during a gate break after molding the resin mold package. Since the resin burr does not remain on the lead frame after that, the damage of the die in the subsequent process is reduced from the conventional 1/200 shots to 0 times, and the lead dents during outer lead molding are not generated. This has the effect of significantly reducing the occurrence rate from the conventional 0.2% to 0%.

Further, there is no need to remove the lead frame in the vicinity of the gate cutout hole together with the resin burr by using a cutting die in the subsequent step, and there is an effect that man-hours and required equipment can be saved.

Further, the accuracy deterioration caused by the conveyance in the subsequent process accompanying the cutting of the hanging pin of the gate portion due to the external force applied when removing it by using the cutting die is eliminated, and the occurrence rate is 0.3% in the past. Contact mistake that occurred, 1
This has the effect of completely eliminating the problem of equipment damage and the like that occurred in 200 shots / time.

[Brief description of drawings]

1A and 1B are a plan view after resin sealing according to a first embodiment of the present invention and a cross-sectional view taken along the line AA ′ in a state of being clamped by a sealing mold.

2 (a) and 2 (b) are a plan view and a sectional view taken along the line BB 'of FIG. 2 after the gate break of the first embodiment of the present invention.

3 (a) and 3 (b) are a plan view after resin sealing according to a second embodiment of the present invention and a cross-sectional view taken along the line C-C 'in a state of being clamped by a sealed mold.

4 (a) and 4 (b) are a plan view after resin sealing of a third embodiment of the present invention and a cross-sectional view taken along the line DD 'in a state of being clamped by a sealed mold.

5 (a) and 5 (b) are a plan view after resin sealing of an example of a conventional lead frame and a cross-sectional view taken along the line EE ′ in a state of being clamped by an encapsulating mold.

6 (a) and 6 (b) are a plan view and a cross-sectional view taken along the line FF ′ of the conventional lead frame after the gate break.

[Explanation of symbols]

 1 Lead Frame 2 Resin Mold Package 3 Gate Notch Hole 4 Outer Lead 5 Slit 6 Half Etch 7 Encapsulating Mold (Upper Mold) 8 Encapsulating Mold (Lower Mold) 9 Runner 10 Sealing Resin 11 Gate Part 12 Resin Burr

Claims (3)

[Claims] 1. A resin-sealed semiconductor having a gate cutout hole at a position intersecting with the gate for melted resin inflow provided in an encapsulating mold for injecting and molding a melted resin to seal a semiconductor element. A lead frame for a semiconductor device, wherein a slit is provided along the periphery in the vicinity of the outside of the gate cutout hole in the device lead frame. 2. A resin-encapsulated semiconductor having a gate cutout hole at a position intersecting with the gate for inflowing the melted resin, which is provided in an encapsulating mold for injecting and molding the melted resin to seal the semiconductor element. A lead frame for a semiconductor device, wherein in the lead frame for a device, a half etch is provided along the periphery in the vicinity of the outside of the cutout hole of the gate portion. 3. The slit or the half etch is formed so that the melted resin covers a region surrounded by an outer periphery of the gate cutout hole and an inner periphery of the slit or the half etch. Alternatively, the lead frame for a semiconductor device described in 2.