JPS62142338A - Package for semiconductor device - Google Patents

Abstract

PURPOSE:To attain excellent mass-production properties by arranging plural lead frames at vertical intervals and molding a device into one body in a manner that external lead parts of the lead frame project from the side plane of a package. CONSTITUTION:Lead frames 10 and 12 are arranged into two stages at constant intervals in vertical direction. In a resin molded part 14, a semiconductor element containing hole 16 is opened in the center and internal lead parts 10a and 12a are exposed on a step part 18 around said hole 16 and are wire bonded to the semiconductor element fixed in the semiconductor element containing the hole 16. The upper and lower lead frames 10 and 12 are independent respectively and are arranged at intervals, so that there is no problem if their plane patterns overlaps one upon another, thereby contriving an increase of the number of pins.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a package for a semiconductor device, and more specifically, a plurality of lead frames are vertically spaced apart and integrally molded to form a multi-bin package. The present invention relates to a package for a semiconductor device that achieves the following.

(Background Art) There is a constant demand for packages for semiconductor devices to be smaller and have more pins.

When trying to increase the number of bins using conventional methods for semiconductor device packages that use conventional lead frames, there is a limit to narrowing the lead spacing and lead width, so the tips of the internal leads must be set back from the element mounting area. As a result, there was no choice but to increase the number of pins while ensuring a predetermined lead spacing and lead width.

However, this increases the distance between the tip of the internal lead and the semiconductor element, which reduces the reliability of wire bonding, and also inevitably increases the area on the external lead side, making the entire semiconductor device package This would lead to an increase in the size of the machine, which is contrary to the above request.

Although a PGA (pin grid array) type semiconductor device package, which is formed by stacking ceramic substrates or PC boards, can have a large number of pins, it requires stacking processing and the manufacturing process involves multiple steps, which inevitably leads to high costs. There is a problem.

Furthermore, those using a PC board are subjected to electroless plating on a single unit, and continuous electrolytic plating cannot be performed like a lead frame, so there is a problem that mass production is poor.

The present invention has been made in view of the various problems mentioned above, and its purpose is to provide a semiconductor that is excellent in mass production and can achieve a large number of pins by integral molding using a lead frame. We provide equipment packages.

(Summary of the invention) The present invention has the following configuration to solve the above problems.

That is, it is characterized in that a plurality of lead frames are arranged vertically at intervals and are integrally molded so that the external lead portions of the lead frames protrude from the side wall surface of the package.

Further, a plurality of lead frames are integrally molded at vertical intervals, the external connection terminals are fixed perpendicularly to the internal lead portions of the lead frames, and the other ends protrude from the package surface.

Furthermore, a plurality of lead frames are integrally molded at intervals vertically, and the external connection terminals are fixed perpendicularly to the internal lead parts of the lead frames, with the other ends protruding from the surface of the mold part, and The lead frame portion protruding from the wall surface is cut out, and is further integrally molded so as to cover at least the side wall surface of the mold part and the external connection terminal protrusion side surface so that the external connection terminal protrudes from the package surface. shall be.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings.

FIG. 1 is a sectional view showing a first embodiment of the present invention.

In the figure, reference numerals 10 and 12 indicate lead frames, which are arranged in two stages vertically at a constant interval.

Reference numeral 14 denotes a resin molded part, in which a semiconductor element storage hole 16 is recessed in the center, internal lead parts 10a and 12a are exposed on a stepped part 18 around the resin mold part, and a semiconductor element is fixed in the semiconductor element storage hole 16. (not shown).

FIG. 2 shows an example of a planar pattern of lead frames 10, 12 arranged one above the other. Upper and lower lead frames 10.
12 are independent and are placed at intervals, so their planar patterns may overlap, which makes it possible to create a large number of bins.

Note that the internal lead portion 10a of the lead frame 10.12
, 12a are dense (particularly when they overlap), the upper and lower internal lead parts 10a can be separated by slightly retracting the ends of the internal lead parts 10a of the upper lead frame 10 as shown in FIG. , 12a should have a sufficient wire bonding area on the top surface.

In addition, by bending one (or both) of the upper and lower internal lead parts 10a and 12a and bringing them closer together as shown in the figure (there is no risk of short circuit because the molded resin is interposed), the inner lead parts 10a and 12a can be bent. It is preferable to make wire bonding easier by reducing the difference in height between the wire bonding area and the top surface of the semiconductor element.

As shown in the figure, a certain space is ensured between the upper and lower external lead parts fob and 12b to prevent short circuits.

In this embodiment, the external lead portion ta of the lead frame is
b and 12b protrude from the side wall of the resin mold 14 as external connection terminals.

By bending the external lead portions 10b and 12b of the lead frame into a desired shape at a predetermined position, the lead frame can be used as a so-called surface mount package, a DIP type package, or the like.

Note that the portion of the stage support par 22 (FIG. 2) that supports the stage portion 20 to which the semiconductor element is fixed, outside the resin mold portion 14, is cut and removed as necessary.

The semiconductor device package in this embodiment is molded by inserting lead frames 10 and 12 and integrally molding them with resin.

Note that the internal lead portions, stage portions, etc. of the lead frames 10 and 12 are preliminarily subjected to necessary plating at the lead frame stage. Therefore, the package can be formed by simply positioning and incorporating the lead frames 10, 12 into a mold and performing insert molding.

In addition, some problems in mold making will be described later.

FIG. 3 shows a second embodiment.

In this embodiment, the external connection terminal is the resin molded part 14.
A lead bin 24 is vertically joined to the inner lead portion 10c12c of the inner lead frame, and is integrally molded so that the lower part of the lead bin 24 protrudes downward from the lower surface of the resin molded portion 14.

The lead pins 24, which serve as external connection terminals, are joined in advance to predetermined positions on the lead frame by soldering or the like, and then incorporated into a mold and integrally molded. In this case, the portion corresponding to the external lead portion of the lead frame shown in the first embodiment (the portion shown by the chain line in FIG. 3, including the stage support bar)
is removed by cutting after molding.

Alternatively, as shown in FIG. 4, insert molding is performed so that a lead bin insertion hole 26 is formed during molding,
After molding, the lead pin 24 whose tip is coated with a solder film, conductive adhesive, etc. is inserted into the lead bin insertion hole 26, and the lead pin 24 is bonded to the internal lead portions 10c, 12G of the lead frame using a bonding agent such as solder. It may be fixed at a predetermined location.

Note that by forming through holes or recesses in the internal lead portions 10c and 12c of the lead frame at the joining positions of the lead pins 24, the lead pins 24 can be positioned well.

Furthermore, a hole (opening) for inserting a joining jig may be provided above the lead bin insertion hole 26 during molding to facilitate lead bin joining.

If the internal lead pattern in the resin molded part 14 of the upper lead frame 10 overlaps the lead pattern of the lower lead frame 12, the upper lead is attached to the corresponding part of the lower lead frame 12. An insertion hole 28 into which a lead pin to be joined to the frame 10 is loosely inserted (having a sufficient size to prevent electrical short circuits)
(Fig. 5) should be provided.

Furthermore, the above-mentioned dashed line section (stage support bar 22
By covering the side wall of the resin mold part 14 at the cut portion (including the lead frame) with an appropriate coating material, it is possible to further prevent moisture from entering the package through the gap between the resin and the lead frame near the cut. can.

FIG. 6 shows a third embodiment.

In this embodiment, the package of the second embodiment is inserted, and a resin is integrally molded on the exterior of the package. The region of the exterior molded portion 30 made of resin corresponds to at least the side wall of the resin molded portion in the second embodiment and the lower surface from which the lead pins, which are external connection terminals, protrude. As a result, the above-mentioned cut portion indicated by the dashed line and the periphery of the lead pin 24 are completely covered with the resin, further improving airtightness, and moisture infiltration from these portions into the package is completely prevented.

Further, if a protruding portion 32 or a groove (not shown) is provided on the outer periphery of the lead pin 24 corresponding to the exterior mold portion 30, moisture intrusion can be further prevented, and the lead pin 24 can be further prevented from entering.
4 can be fixed even more firmly.

In this embodiment, in addition to using the same material as the resin mold part 14 as the exterior resin material to prevent thermal distortion, a material with particularly low permeability is used to ensure airtightness.
It is possible to maintain f1 and prevent moisture from entering.

In each of the above embodiments, two lead frames are arranged one above the other, but it goes without saying that three or more lead frames may be used.

Next, the problems encountered during molding and their solutions are shown below.

In the present invention, a plurality of lead frames are arranged vertically at intervals. Therefore, the resin molded portion where the upper and lower lead frame patterns overlap has a problem in that the resin leaks from this portion during molding.

FIG. 7 shows a first solution to the above problem. In this case, the resin mold part 14 and the external lead part 10b of the lead frame
, 12b, a resin plate 34 is inserted between the upper and lower lead frames 10, 12. This prevents resin from leaking.

FIG. 8 shows the second solution. In this case, the resin mold part 14 and the external lead parts LQb, L2 of the lead frame
The base of the external lead part 10b, which forms the boundary with the outer lead part 10b, is bent at right angles to bring the upper and lower external lead parts 10b and 12b into contact with each other to form a bag-like shape, thereby preventing leakage of resin. After molding, the external lead portions 10b, 12b of the lead frame are cut and removed. Therefore, this example is similar to the second and third embodiments, in which the external connection terminal is a lead-bin junction type.
It is commonly used as a universal package for semiconductor devices.

Note that leakage of the resin can also be prevented by making the boundary between the internal lead part and the external lead part of the lead frames arranged above and below have a staggered shape.

(Effects of the Invention) As described above, according to the semiconductor device package according to the present invention, it is possible to increase the number of bins using a lead frame.

In addition, it can be easily integrally molded by insert molding, and the manufacturing process is significantly simplified compared to conventional PGA type semiconductor device packages, which can also have a large number of pins.

In addition, not only the required continuous plating process but also the insert molding process can be performed continuously using the lead frame of the ward, and the subsequent semiconductor element mounting process can be carried out with the long body as well, making it extremely possible for mass production. An efficient manufacturing method with excellent properties can be adopted.

Although the present invention has been variously explained above with reference to preferred embodiments, the present invention is not limited to these embodiments, and it goes without saying that many modifications can be made without departing from the spirit of the invention. That's true.

[Brief explanation of drawings]

1 is a sectional view showing a first embodiment of the package for a semiconductor device according to the present invention, FIG. 2 is an explanatory view showing an example of a planar pattern of upper and lower lead frames, Figure 3 is a sectional view showing the second embodiment, Figure 4 is an explanatory diagram of the case where lead pins are joined after molding, and Figure 5 is an explanatory diagram showing the glue-do-pin joining method when upper and lower lead frame patterns overlap. , FIG. 6 is a cross-sectional view showing the third embodiment, and FIGS. 7 and 8 are explanatory views showing a resin leakage prevention method, respectively. 10.12... Lead frame, 14... Resin mold, 16... Semiconductor element storage hole, 18... Step portion,
10a, 12a...inner lead part, 10b, 12b...
...External lead part, 20... Stage, 22... Stage support bar, 24... Lead bin, 26... Lead pin insertion hole, 28... Insertion hole, 3o... Exterior mold, 32・
...Protruding periphery.

Claims (1)

[Scope of Claims] 1. A package for a semiconductor device, which is formed by integrally molding a plurality of lead frames vertically spaced apart from each other so that the external lead portions of the lead frames protrude from the side wall surface of the package. 2. A semiconductor device package comprising a plurality of lead frames integrally molded at vertical intervals, external connection terminals fixed perpendicularly to internal lead portions of the lead frames, and the other end protruding from the package surface. 3. A plurality of lead frames are integrally molded at vertical intervals, and the external connection terminals are fixed perpendicularly to the internal lead parts of the lead frames, with the other ends protruding from the surface of the mold part, and For a semiconductor device, the lead frame portion protruding from the wall surface is cut off, and further integrally molded to cover at least the side wall surface of the mold part and the surface on the side where the external connection terminal protrudes, so that the external connection terminal protrudes from the package surface. package.