JPH0878596A - Lead frame use resin-encapsulating device and semiconductor device use lead frame - Google Patents

Abstract

PURPOSE: To obtain a lead frame use resin-encapsulating device of a structure, wherein both the moldability and the positioning accuracy are satisfied and at the same time, a positioning hole bored in the lead frame can be prevented from being buried in resin burrs, and the semiconductor device use lead frame. CONSTITUTION: In the case where a lead frame 2 is placed between resin- encapsulating use top and bottom forces 1 and 3, an opening part 6 for making a resin, which oozes out from cavities 1a and 3a formed in the forces 1 and 3 into air vents 1d and 3d formed in these forces 1 and 3, stop is formed on this side of a positioning hole 2a, which is bored in the frame 2 and faces the air vents 1d and 3b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention, when a lead frame on which a semiconductor element is mounted is sealed with a molding resin, the resin exuded from an encapsulating mold to an air vent is positioned on the lead frame. The present invention relates to a resin sealing device for a lead frame and a lead frame for a semiconductor device, which can prevent the resin from entering the hole.

[0002]

2. Description of the Related Art Generally, a resin encapsulation device for a lead frame of a semiconductor device clamps two upper and lower molds mounted on a transfer molding press, and then a resin tablet in a transfer pot is clamped by a plunger. It is known that pressure is applied to the inside to perform molding.

Conventionally, this type of resin sealing device has an upper mold having a transfer pot in which a plunger for pressurizing a resin tablet advances and retracts in the center thereof, and a cavity forming one package, and an upper mold. A lower mold having a cavity (resin sealing portion) that is provided so as to be movable back and forth and forms the other package,
The one provided with an ejecting mechanism having an ejector pin that advances and retracts inside each cavity housed in each of the lower mold and the upper mold is used.

The positional relationship between the positioning holes of the lead frame sandwiched between the upper mold and the lower mold of the resin sealing device and the air vents (air flow paths) communicating with the outside in the cavities of the upper mold and the lower mold. Is constructed as shown in FIGS. 9 and 10 are plan views of the lead frame for the DIP type package, FIG. 11 is a plan view of the lead frame for the QFP type package, and FIG. 12 is a cross-sectional view of the resin encapsulating device sandwiching the lead frame. Here, the configuration of the resin sealing device will be described by taking the cross-sectional view of FIG. 12 as an example. In the figure, 1 is an upper die of a resin sealing device, 1
a is an upper mold cavity (resin sealing space) formed in the upper mold 1, 1b. Reference numeral 1c is a runner gate formed on the upper mold 1 for filling the cavity with resin, and 2 is a lead frame die-bonded with a semiconductor element (not shown) in the center. The semiconductor element and the internal lead (not shown) are wire-bonded with, for example, a gold wire.

Reference numeral 2a is a positioning hole provided in the outer frame of the lead frame 2. Although not shown, the positioning hole 2a is an apparatus for performing each step in a die bonding step, a wire bonding step, a molding step, a lead processing step, or the like. It is a hole used for positioning with the lead frame and is processed with high precision.

Reference numeral 3 denotes a lower mold, and a lower mold cavity 3a is formed so as to face the upper mold cavity 1a of the upper mold 1. 1d and 3b are air vents provided on the opposite side of the liner gate 1c of the upper cavity 1a and the lower cavity 3a, and the upper mold cavity 1a and the lower mold cavity 3a are communicated with the outside by air vents 1d and 3b. .

A mold resin (not shown) for molding the lead frame 2 is provided with a runner gate 1 of a resin sealing device.
When injected from b and 1c, the flow direction of mold resin is 4
Go to a → 4b → 4c. And the upper mold cavity 1
a, when the lower mold cavity 3a is filled with the mold resin, the air 5 in each of the cavities 1a and 3a and the mold resin is pushed out to the outside in the direction of 4d through the air vents 1d and 3b. A good package is formed that does not occur.

When the mold resin is pressure-fed to the cavities 1a and 3a, as shown in FIG. 9 or 10, the mold resin exudes in a thin film form together with the air 5 from the cavities 1a and 3a to the air vents 1d and 3b. Sometimes. This is generally called an air vent burr (hereinafter simply referred to as burr). The burr is provided on the lead frame 2 so that the positioning hole 2a is not blocked, and the position of the positioning hole 2a is determined by avoiding the air vents 1d and 3b, or by sandwiching the positioning hole 2a as shown in FIG. Two types of air vents 1d and 3b were formed.

[0009]

As described above, the resin encapsulation device for a lead frame and the lead frame for a semiconductor device according to the related art determine the position of the air vent or the positioning hole so that the air vent and the positioning hole relatively overlap each other. I was trying not to fit. However, due to the moldability of the resin sealing device, the air vent is an external lead (2b in FIGS. 9 and 10).
It is better to take the maximum width unless it interferes with.

Further, in terms of the positioning property in each manufacturing process of the semiconductor device, it is best to set the positioning hole in a region which does not interfere with the external lead. As a result, as shown in FIG. 11, the air vent and the positioning hole compete with each other, and when trying to avoid the competition, a problem arises in terms of moldability or positioning. Therefore, as shown in FIG. 11, if the positioning hole is set in a region where it does not interfere with the external lead and the air vent is also set at a position where it does not interfere with the external lead, the mold resin exuded from the air vent is resin. There is a problem in that the positioning holes are buried as burrs and the positioning accuracy is lowered, and the product quality is lowered.

The present invention has been made in order to solve the above problems, and it is possible to satisfy both the moldability and the positioning property and prevent the positioning hole from being buried by the resin burr. An object of the present invention is to obtain a resin sealing device and a lead frame for a semiconductor device.

[0012]

According to another aspect of the present invention, there is provided a resin encapsulation device for a lead frame, wherein when the lead frame is placed on a resin encapsulation mold, an air vent in the mold is An obstacle is formed between the positioning hole of the lead frame and the air vent, which stops the resin exuding from the resin sealing portion of the mold into the air vent.

According to a second aspect of the present invention, there is provided a lead frame positioning hole for a semiconductor device, wherein when the lead frame is mounted on a resin-sealing die, an air vent in the die is exposed. In front of the above, an obstacle for stopping the resin that has exuded to the air vent from the resin sealing portion of the mold is formed.

The lead frame for a semiconductor device according to a third aspect of the present invention is the lead frame for a semiconductor device according to the second aspect, in the longitudinal direction before the positioning hole of the lead frame where the air vent in the mold is exposed. The opening is provided.

A lead frame for a semiconductor device according to a fourth aspect of the present invention is the lead frame for a semiconductor device according to the second aspect, wherein the lead frame for the semiconductor device is longitudinally arranged in front of the positioning hole of the lead frame where the air vent in the mold is exposed. A plurality of openings are provided.

The lead frame for a semiconductor device according to a fifth aspect of the present invention is the lead frame for a semiconductor device according to the second aspect, in the longitudinal direction before the positioning hole of the lead frame where the air vent in the mold is exposed. It has a depression.

According to a sixth aspect of the present invention, there is provided a resin encapsulation device for a lead frame, wherein when the lead frame is placed on a resin encapsulation die, air in the die facing the positioning hole of the lead frame is exposed. A groove is formed in the vent to store the resin that has exuded from the resin sealing portion of the mold in front of the positioning hole.

According to a seventh aspect of the present invention, there is provided a resin encapsulating device for a lead frame, wherein when the lead frame is placed on a resin encapsulating die, air in the die facing a positioning hole of the lead frame is exposed. A step is formed in the vent so that the resin that has exuded from the resin sealing portion of the mold escapes from the positioning hole.

[0019]

In the lead frame sealing device according to the first aspect of the present invention, since the obstacle for stopping the resin oozing from the resin sealing portion of the mold to the air vent is formed, the resin is inserted into the positioning hole from the air vent. The positioning hole can be arranged on the extension line of the air vent without letting it flow in.

In the semiconductor device lead frame according to the second aspect of the present invention, the resin exuding from the resin sealing portion of the mold to the air vent is stopped before the positioning hole of the lead frame where the air vent in the mold is exposed. Since the obstacle to be formed is formed, the positioning hole can be arranged on the extension line of the air vent, and the contamination of the mold by the exuded resin can be suppressed as much as possible.

In the lead frame for a semiconductor device according to the third aspect of the present invention, since the opening is provided in the longitudinal direction in front of the positioning hole of the lead frame where the air vent in the mold is exposed, the positioning hole extends the air vent. It can be arranged on the line and can prevent the resin exuded widely from flowing into the positioning hole.

In the lead frame for a semiconductor device according to the invention of claim 4, since a plurality of openings are provided in parallel in the longitudinal direction in front of the positioning hole of the lead frame where the air vent in the mold is exposed, the positioning hole is formed. It can be arranged on the extension line of the air vent, and can more effectively block the inflow of resin.

In the lead frame for a semiconductor device according to the invention of claim 5, since a recess is provided in the longitudinal direction in front of the positioning hole of the lead frame where the air vent in the mold is exposed, the positioning hole is formed on the extension line of the air vent. In addition, the resin can be attached to the mold and the adhesion of the resin to the mold can be minimized.

According to the sixth aspect of the present invention, in the lead frame sealing device, when the lead frame is mounted on a resin sealing die, a metal is attached to an air vent in the die which faces a positioning hole of the lead frame. Since the groove for storing the resin exuding from the resin sealing portion of the mold is formed in front of the positioning hole, it is possible to prevent the resin from flowing into the positioning hole without processing the lead frame.

According to a seventh aspect of the present invention, in the lead frame sealing device, when the lead frame is mounted on a resin sealing mold, a metal is attached to an air vent in the mold facing a positioning hole of the lead frame. Since a step is formed in which the resin that has exuded from the resin sealing portion of the mold escapes from the positioning hole, it is possible to prevent the resin from flowing in with a mold having an extremely simple structure.

[0026]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a DIP type semiconductor lead frame in this embodiment. In the figure, the same reference numerals as those in FIG. 9 indicate the same or corresponding portions. In FIG. 1A, 6 is a rectangular opening as an obstacle. The opening 6 is formed on the lead frame 2 in the upper mold cavity 1a.
And an opening in front of the positioning hole 2a on the extension line of the air vent (not shown) provided in the lower mold cavity 3a. Although the opening 6 has a rectangular shape, the shape of the opening 6 may be any shape as long as the opening is wider in the longitudinal direction than the diameter of the positioning hole 2a.

Although the opening 6 is shown as a single in FIG. 6 (a), even if a plurality of square holes are arranged in parallel as shown in FIG. 4 (b), intrusion of the mold resin can be effectively prevented. . This is because it is possible to prevent the mold resin from entering each square hole.

FIG. 2 is a plan view of a QFP type lead frame for a semiconductor device. In the case of the QFP type lead frame, each positioning hole 2a is opened on the extension of each diagonal of the die pad in order to avoid interference with the external lead 2b extending from each side of the die pad. Moreover, the air vents (not shown) in the upper mold 1 (see FIG. 3) and the lower mold 3 (see FIG. 3) are also formed in accordance with the diagonal lines. Each opening 6 is opened in front of each positioning hole 2a on each diagonal.

Although the opening 6 has a square shape, it may have any shape as long as it has an opening wider in the longitudinal direction than the diameter of the positioning hole 2a. Further, as shown in FIG. 1 (b), even if a plurality of square holes are arranged in parallel, it is possible to effectively prevent the mold resin from entering.

FIG. 3 is a sectional view taken along the line AA of FIG. In the figure, the same reference numerals as those in FIG. 12 indicate the same or corresponding parts. As is clear from the figure, an opening 6 is formed in the outer frame of the lead frame 2 before the positioning hole 2a.

Next, the operation of this embodiment will be described with reference to the plan view of the semiconductor lead frame shown in FIG. When the mold resin is pressure-fed to each cavity 1a, 3a, each cavity 1
Along with the air 5, the mold resin may form a thin film from a and 3a and may exude to the lead frame 2 in the air vents 1d and 3b.

The resin burr 5 becomes a resin reservoir 7 and penetrates between the air vents in the direction of the positioning hole 2a by a capillary phenomenon. However, when it reaches the opening 6, it adheres along the edge of the opening 6, so Never proceed to. Therefore, the molding resin provided in the lead frame 2 does not reach the positioning hole 2a.

Example 2. In the first embodiment described above, in the lead frame 2, the opening 6 is provided in front of the positioning hole 2a, and the mold resin exuded to the outer frame of the lead frame 2 from the air vent 1d or 3b is dropped into the opening 6. Instead of providing the opening 6 that completely penetrates the lead frame 2, the lead frame 2 may be etched to a predetermined depth to form a recess (half etch) instead of the opening 6.

FIG. 5 is a plan view of the lead frame in this embodiment. In the figure, the same reference numerals as those in FIG. 1 indicate the same or corresponding parts. In the figure, 6a is a half etch formed by etching the lead frame 2 to a predetermined depth. By forming the half etch 6a in this way, the resin burr 5 becomes a resin reservoir 7 and the positioning hole 2a is formed.
Although it penetrates in the direction, it does not fall into the half etch 6a and proceed to the destination. Therefore, the mold resin provided on the lead frame 2 does not reach the positioning hole 2a.

FIG. 6 is a plan view of a lead frame for the QFP package type. This lead frame 2 is shown in FIG.
Similarly, the positioning holes 2a are provided on the extension of the diagonal lines of the die pad, and the air vents (not shown) are also formed in accordance with the diagonal lines. Then, on each diagonal, the lead frame 2 is etched to a predetermined depth before each positioning hole 2a to form a half etch 6a. Thus, instead of the opening 6, the half etch 6a
By forming the mold, the mold resin does not flow down to the mold, so that the mold can be easily cleaned.

Example 3. In each of the first and second embodiments described above, the lead frame was processed to prevent the molding resin from flowing into the positioning hole. However, the air vents 1d and 3b of the upper mold 1 and the lower mold 3 were processed to position the positioning hole 2a. It may be possible to prevent the mold resin from flowing into the. FIG. 7 is a cross-sectional view of the lead frame resin sealing device in this embodiment on which the semiconductor lead frame is mounted. In the figure, the same reference numerals as those in FIG. 3 indicate the same or corresponding portions. In this embodiment, the lead frame 2 has no opening 6 (see FIG. 3).
In the figure, 1e is a dimple-shaped groove formed in the air vent 1d of the upper mold 1, and 3c is a dimple-shaped groove formed in the air vent 3b of the lower mold 3. The position of each groove 1e, 3c is
The upper die 1 and the lower die 3 are located in front of the positioning hole 2a in the lead frame 2 sandwiched between the upper die 1 and the lower die 3.
To form.

Next, the operation of this embodiment will be described.
When the mold resin is pressure-fed to the cavities 1a and 3a, the mold resin becomes a thin film together with air from the cavities 1a and 3a, and exudes into the lead frame 2 in the air vents 1d and 3b to form burrs.

The burr penetrates the air vent in the direction of the positioning hole 2a by a capillary phenomenon, but the air vent 1
The burr exuding on d adheres along the corners of the groove 1e and thus does not proceed further. The burr exuding to the air vent 3b is accumulated in the groove 3e and does not proceed to the tip. Therefore, the mold resin exuded from the cavities 1a and 3a through the air vents 1d and 3b does not reach the positioning hole 2a provided in the lead frame 2.

Embodiment 4 FIG. In the third embodiment, the air vents 1d and 3b are formed by forming the grooves 1e and 3e in the air vents 1d and 3b to prevent the burrs from entering the positioning hole 2a.
The lateral width of each groove 1e, 3e provided in the middle of b may be extended to the ends of the upper die 1 and the lower die 3 to widen the vertical width of the air vent to form a step.

FIG. 8 is a sectional view of the lead frame resin sealing device in this embodiment on which the semiconductor lead frame is mounted. In the figure, the same reference numerals as those in FIG. 7 indicate the same or corresponding parts. In the figure, 1d and 3b are an upper mold 1 and a lower mold 3.
The conventional air vents 1f and 3d provided in the upper mold 1 are wider than the air vents 1d and 3b in the vertical direction, and are formed between the air vents 1d and 1f of the upper mold 1.
A step is provided between the air vents 3b and 3d of the lower mold.

Next, the operation of this embodiment will be described.
When the mold resin is pressure-fed to the cavities 1a and 3a, the mold resin becomes a thin film together with air from the cavities 1a and 3a, and exudes into the lead frame 2 in the air vents 1d and 3b to form burrs.

Burrs are capillarity and air vents 1d, 3
Although it penetrates in the direction of the positioning hole 2a along b, the vertical width of the air vents 1f and 3d becomes wider when reaching the air vents 1f and 3d, so that the resin burr that has exuded becomes the air vents 1d and 3b. The air vents 1f and 3d do not adhere to the stepped portions and proceed further. Therefore, the mold resin exuded from the cavities 1a and 3a through the air vents 1d and 3b does not reach the positioning hole 2a provided in the lead frame 2.

[0043]

According to the first aspect of the present invention, when the lead frame is placed on the mold for resin encapsulation, the air vent in the mold faces the positioning hole of the lead frame and the air. An obstacle was formed between the vent and the resin sealing part of the mold to stop the resin that oozes out to the air vent, so the positioning hole can be extended without the resin flowing into the positioning hole from the air vent. Since they can be arranged on the line, the moldability of the resin encapsulation can be improved, and highly accurate positioning can be performed in each manufacturing process of the semiconductor device, which further improves productivity and makes the semiconductor device inexpensive. The effect is that you can do it.

According to the second aspect of the present invention, when the lead frame is placed on the mold for resin sealing, the mold is provided in front of the positioning hole of the lead frame where the air vent in the mold is exposed. Since the obstacle that stops the resin exuding from the resin sealing portion to the air vent is formed, in addition to the effect of claim 1, there is an effect that contamination of the mold by the exuding resin can be suppressed as much as possible. is there.

According to the invention of claim 3, in the lead frame for a semiconductor device according to claim 2, an opening is provided in the longitudinal direction before the positioning hole of the lead frame where the air vent in the mold is exposed. Therefore, in addition to the effect of the second aspect, there is an effect that it is possible to surely prevent the resin exuded widely from flowing into the positioning hole.

According to the invention of claim 4, in the lead frame for a semiconductor device according to claim 2, a plurality of openings are provided in the longitudinal direction in front of the positioning hole of the lead frame where the air vent in the mold is exposed. Since they are arranged in parallel, in addition to the effect of the second aspect, there is an effect that the inflow of resin can be blocked more effectively.

A semiconductor device lead frame according to a fifth aspect of the present invention is the semiconductor device lead frame according to the second aspect, wherein the lead frame for the semiconductor device is longitudinally arranged in front of a positioning hole of the lead frame facing the air vent in the mold. Since the depression is provided, in addition to the effect of the second aspect, it is possible to minimize the adhesion of the resin to the mold, and thus it is possible to easily clean the mold.

According to a sixth aspect of the present invention, there is provided a resin encapsulating device for a lead frame, wherein when the lead frame is placed in a resin encapsulating die, air in the die facing a positioning hole of the lead frame is exposed. A groove is formed in the vent to store the resin that has exuded from the resin sealing portion of the mold in front of the positioning hole. Therefore, in addition to the effect of claim 1, there is no need to process the lead frame to be mounted. Since the resin can be prevented from flowing into the positioning hole, the versatility is improved.

According to a seventh aspect of the present invention, there is provided a resin encapsulating device for a lead frame, wherein when the lead frame is placed on a resin encapsulating die, air in the die facing a positioning hole of the lead frame is exposed. Since a step is formed in the vent so that the resin that has exuded from the resin sealing portion of the mold escapes from the positioning hole, the inflow of resin can be prevented by the mold having an extremely simple structure in addition to the effect of claim 6. There is an effect.

[Brief description of drawings]

FIG. 1 is a plan view of a lead frame for a DIP type package according to an embodiment of the present invention.

FIG. 2 is a plan view of a lead frame for a QFR type package according to an embodiment of the present invention.

FIG. 3 is a sectional view of a lead frame sealing device on which a semiconductor lead frame according to an embodiment of the present invention is mounted.

FIG. 4 shows a DI according to the present embodiment in which the operation of the opening is explained.
It is a top view of the lead frame for P type packages.

FIG. 5 is a plan view of a lead frame for a DIP type package according to another embodiment of the present invention.

FIG. 6 is a plan view of a lead frame for a QFP type package according to another embodiment of the present invention.

FIG. 7 is a cross-sectional view of a lead frame sealing device according to an embodiment of the present invention on which a semiconductor lead frame is mounted.

FIG. 8 is a cross-sectional view of a lead frame sealing device according to another embodiment of the present invention on which a semiconductor lead frame is mounted.

FIG. 9 is a plan view of a lead frame for a DIP type package mounted on a conventional lead frame sealing device.

FIG. 10 is a plan view of a lead frame for a DIP type package mounted on a conventional lead frame sealing device.

FIG. 11 is a plan view of a conventional lead frame for a QFP type package mounted on a conventional lead frame sealing device.

FIG. 12 is a cross-sectional view of a conventional lead frame sealing device on which a semiconductor lead frame is mounted.

[Explanation of symbols]

1 Upper mold, 2 Lead frame, 3 Lower mold, 1a
Upper mold cavity, 1d upper air vent, 1e groove, 1
f Air vent, 2a Positioning hole, 2b External lead, 3a Lower mold cavity, 3b Lower cavity, 3
c groove, 3d air vent, 6 opening, 6a depression.

Claims (7)

[Claims] 1. A mold resin between a positioning hole of the lead frame where an air vent in the mold is exposed when the lead frame is placed on a mold for resin sealing and the air vent. A resin encapsulation device for a lead frame, wherein an obstacle for stopping the resin exuding from the encapsulation portion to the air vent is formed. 2. When the lead frame is placed on a mold for resin encapsulation, the resin encapsulation portion of the mold is provided in front of a positioning hole of the lead frame where an air vent in the mold is exposed. A lead frame for a semiconductor device, characterized in that an obstacle is formed on the air vent to stop the resin oozing out. 3. The lead frame for a semiconductor device according to claim 2, wherein an opening is provided in the longitudinal direction before the positioning hole of the lead frame where the air vent in the mold is exposed. 4. The lead frame for a semiconductor device according to claim 2, wherein a plurality of openings are provided in the longitudinal direction in front of the positioning hole of the lead frame where the air vent in the mold is exposed. 5. The lead frame for a semiconductor device according to claim 2, wherein a recess is provided in the longitudinal direction before the positioning hole of the lead frame where the air vent of the mold is exposed. 6. When the lead frame is placed on a mold for resin encapsulation, it exudes from the resin encapsulation portion of the mold to an air vent in the mold facing the positioning hole of the lead frame. A resin encapsulation device for a lead frame, wherein a groove for accumulating the resin in front of the positioning hole is formed. 7. When the lead frame is placed on a mold for resin encapsulation, it oozes out from the resin encapsulation part of the mold to an air vent in the mold facing the positioning hole of the lead frame. A lead frame resin encapsulation device, wherein a step is formed to allow the resin to escape from the positioning hole.