JPS60107848A - Semiconductor device and lead frame used for said device - Google Patents

Abstract

PURPOSE:To miniaturize a semiconductor device by arranging a plurality of leads constituting a lead frame at two steps in zigzag manner, bending the leads in sections projected to the outside to a L shape and bringing both bottoms of the leads arranged at two steps to the same planes as the bottom of a resin package in the semiconductor device having a shape in which a semiconductor element is fixed onto the lead frame and the lead frame is received in the resin package. CONSTITUTION:A semiconductor element is fastened to a semiconductor loading section for a lead frame, and the semiconductor loading section is sealed in a resin package 2 while projecting lead end sections in the frame, thus manufacturing a semiconductor device 1. In the constitution, leads 3 are formed in two-step structure while being zigzag arranged, and the end sections of each lead 3 are bent downward to a L shape in external projecting sections, and the bottoms of the external projecting sections are aligned with the bottom of the package 2 and formed in the same surface. Accordingly, the size of the package 2 may be small, and the device 1 is miniaturized by that much.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a semiconductor device and a lead frame used in its manufacture, and relates to a technology that can achieve miniaturization of specialized semiconductor devices.

[Background technology]

As semiconductor devices become more dense and multi-functional, the number of external terminals (leads) increases and semiconductor devices tend to become larger. There is a strong desire for miniaturization. Even in resin molded semiconductor devices in which the main parts such as chips are covered with a resin package, electronic materials 1980 1
October issue, pages 121-124 [As described in the mini-flat IOJ, further miniaturization has been attempted.

By the way, conventional resin molded semiconductor devices are manufactured using plate-shaped lead frames, as described in "Lead Frame", pages 69-74 of Electronic Materials, August 1982, for example.

However, in manufacturing semiconductor devices using such lead frames, the inventors have found that it is difficult to miniaturize a product group with a large number of leads for the following reasons.

That is, since the lead frame is formed from one plane plate, the leads are arranged on the same plane. As the number of leads increases, the lead pitch is designed to be smaller, but there is a limit from the viewpoint of preventing short circuits. Also,
From the point of view of miniaturizing the lead frame, it is conceivable to reduce the lead width in addition to reducing the lead pitch. However, as the number of leads increases, the dimensions of the resin package increase, and the length of the leads (inner leads) extending inside the resin package increases, causing a decrease in the strength of the leads. As a result, there is a limit to the reduction in the width of the inner leads, and as the number of leads increases, the package dimensions gradually increase.

On the other hand, in the case of resin packages, as the size of the package increases, the flow of resin into the cavity of the mold during resin molding becomes complicated, which increases the likelihood of defects such as voids (bubbles), resulting in poor product quality. The inventors have also found that this may lead to a decrease in .

[Purpose of the invention]

An object of the present invention is to prevent malfunctions of semiconductor devices.

The above and other objects and novel features of the present invention include:
It will become clear from the description of this specification and the accompanying drawings.

[Summary of the invention]

A brief overview of typical inventions disclosed in this application is as follows.

That is, in the present invention, a lead frame is constructed of two sub-lead frames superimposed in parallel, and a semiconductor device is manufactured using these lead frames. The leads of the sub-lead frame are arranged in two stages in a staggered manner, located above or below the leads of other sub-lead frames.

Further, the leads are bent one step upward or downward near the inner end, and the wire connection portions at the inner end are all on the same plane. Therefore, in a semiconductor device manufactured using such a lead frame, the leads are arranged in two stages in a staggered manner inside and outside the package.
It is smaller than a conventional semiconductor device in which leads are arranged in one row.

〔Example〕

FIG. 4 is a front view of a semiconductor device according to an embodiment of the present invention;
FIG. 2 is a plan view, FIG. 3 is a side view, FIG. ) and (b) are partially sectional views, and FIG. 6 is a perspective view showing the main parts of the lead frame.

As shown in FIGS. 1 to 3, a resin mold type semiconductor device 1 has a structure in which leads 3 protrude in two stages in a staggered manner from both sides of a resin package 2. Also,
Each lead 3 is bent one step in the middle, and the lower surface of the tip is formed to be approximately flush with the lower surface of the resin package 2, forming a so-called surface mount structure. Each lead 3 is arranged in two stages in a staggered manner in a plane perpendicular to its extending direction. As will be described later, this arrangement is similar within the resin package 2, except for the inner end. In addition, by making the pitch between adjacent leads (lead pitch) the same as a when considering the leads as wire rods, the dimensions of the resin package 2 in the plane direction and the height direction perpendicular thereto are minimized. be able to.

Such a semiconductor device 1 has a dimension in the lead arrangement direction that is half that of a conventional semiconductor device with a single line of leads. Therefore, from both sides of the resin package 2,
In the protruding semiconductor device of this embodiment, the size and area of the resin package 2 is half that of a conventional semiconductor device.

Next, a method for manufacturing (assembling) such a semiconductor device 1 will be explained, and the inside of the resin package 2 will also be explained. In assembling the semiconductor device 1, a lead frame 4 as shown in FIG. 6 is used. This lead frame 4 is composed of two sub lead frames 5 and 6 as shown in FIGS. 6, the protruding connecting portions 9 of the frame frames 7, 8,
It is fixed by 100% welding and has an integrated structure.

As shown in FIG. 4(a), one of the sub lead frames 5 and 6 has a tab 11. A tab suspension lead 12 for connecting the tab 11 to the frame frame 7. A plurality of glue boards with their inner ends facing the tabs 11 3. Tie bar 1 that supports lead 3 on frame frame 7
3. It consists of a dam 14 that plays a role in stopping the flow of resin during resin molding. Further, in this sub-lead frame 5 with tabs, the inner ends of the tabs 11 and leads 3 are lowered as shown in FIG. 5(a). For this reason, the tab suspension lead 12 and the lead 3 are bent in one step in the middle. Note that a semiconductor element (chip) 15 is fixed on the upper surface of the tab 11, and the electrodes of the chip 15 are fixed to the upper surface of the tab 11.
A wire connection portion 16 at the inner end of the card 3 is connected with a wire 17. At this time, the wire 17 hangs down and contacts the chip 15 with green contact, which tends to cause a short circuit failure. Therefore, in this example, the tab 11 is made even more slender than the inner end of the lead 3 so that the upper surface of the chip 15 substantially coincides with the surface of the wire connection portion 16 of the lead 3.

On the other hand, the tab-less sub-lead frame 6 located below the tab-equipped sub-lead frame 5 shown in FIG. Frame frame 8. Tie bar 18
．． It has a dam 19.

However, the tab 11 like the tab-equipped sub lead frame 5
And the tab lead 12 is not included. Also, lead 3
has the same structure as the tab-equipped sub-lead frame 5, but
Its position is 5th sub IJ-de frame with tab when viewed from above.
The leads 3 are arranged such that one lead is located in the middle of each lead 3. In addition, the sub lead frame 6 without tabs is the fifth
As shown in Figure (b), the inner end of the lead 3 is bent upward in one step. The inner end portion of the lead that is bent and becomes horizontal becomes a wire connection portion 20 . When the sub-lead frame 5 with tabs and the sub-lead frame 6 without tabs are stacked and integrated, this wire connection part 20 is positioned on the same plane as the wire connection part 16 of the sub-lead frame 5 with tabs. It has become.

This is because, although not particularly limited, it is difficult to connect when the height of the wire connection portion on the lead side increases or decreases during wire bonding.

Therefore, in the case of a wire bonding apparatus that can reliably connect wires even if the height of the wire connection portion on the lead side is not constant, it is not necessary to make the inner ends of the leads in both lead frames 5 and 6 on the same plane. Note that by arranging the leads 3 in two stages in a staggered manner, the lead frame 4 and the resin package 2 can be made smaller. On the other hand, in the embodiment, the inner end of the lead is one step, but this is because the inner end of the lead becomes the wire connection part 16.20, so if there is an area (thickness) necessary for wire connection, then This is often due to the fact that it does not require as much mechanical strength as other IJ-lead parts, so it can be made thinner than other lead parts. The present invention has achieved miniaturization by focusing on this point.

Such a lead frame 4 has a chip 15 on the tab 11.
is connected. Further, the electrodes of the chip 15 and corresponding wire connection portions 16 and 20 at the inner end of the negative electrode 3 are electrically connected by wires 17.

Next, as shown in FIG. 6, the area surrounded by the frames 7, 8 and the dams 14, 19 is covered with a resin package 2 made of resin mold. Thereafter, unnecessary lead frame portions are cut and removed, and lead portions protruding from the resin cage 2 are molded to produce a semiconductor device as shown in FIGS.

〔effect〕

(1) In the present invention, since the leads are arranged in two stages in a staggered manner both inside and outside the resin package, it is possible to achieve miniaturization of the semiconductor device.

(2) In the present invention, the leads of the lead frame are arranged in two stages in a staggered manner, including an inner lead portion that is resin-molded and an outer lead portion that is not resin-molded. As a result, the resin mold area does not become large, and deterioration of resin inflow conditions during resin molding due to enlargement can be prevented.For example, the generation of voids (bubbles) in the resin package can be reduced, and moisture resistance can be improved. Improvements can be made.

(3) Considering the present invention from the point of view of assembly processing equipment, even if the number of leads is increased, the lead frame will not be significantly enlarged. As a result, the assembly processing equipment does not need to be large-sized, and equipment costs can be reduced.

(4) Similarly, even if the number of leads increases, the lead frame does not become large in size, making it easy to handle and highly workable.

(5) Due to the above (1) to (4), a synergistic effect can be obtained in that a compact and high quality semiconductor device can be provided at a low cost.

Although the invention made by the present inventor has been specifically described above based on examples, it goes without saying that the present invention is not limited to the above-mentioned examples, and can be modified in various ways without departing from the gist thereof. Nor. For example, in the embodiment described above, the leads of both sub-lead frames were bent in order to align the inner ends of the leads on the same plane, but this may be structured so that only one of the leads is bent. FIG. 7 shows an example in which the leads 3Y of the sub-frame 5 with tabs are not bent, but the leads 3 of the sub-lead frame 6 without tabs are bent. Even with this structure, the same effects as in the above embodiment can be obtained.

Further, as shown in FIGS. 8(a) and (b), the present invention
It can be similarly applied to a semiconductor device 1 in which the resin package 2 has a gate 3 protruding from its four sides, or a semiconductor device 1 having a pull-in-line structure as shown in FIG. You can get an effective power ball.

In particular, a semiconductor device 1 with leads 3'L' protruding from the 411 plane.
In this case, the resin package 2 can be made smaller in terms of area, so the effect of smaller size is greater.

Note that Figures 9(a) and (b) are similar to Figures 8(a) and (b).
)K are the sub-lead frames 5 and 6 used for assembling the semiconductor device 1 shown in FIG. 6, but the only difference from the lead frame 4 shown in FIG. Since they are the same, their explanation will be omitted.

[Application field]

The above explanation has mainly been about the case where the invention made by the present inventor is applied to the resin mold type semiconductor device manufacturing technology, which is the field of application that is the background of the invention.
The present invention is not limited thereto, and can be applied, for example, to manufacturing techniques for articles in which a large number of rods protrude from a package in terms of miniaturization of articles.

Furthermore, the present invention can also be applied to ceramic-sealed semiconductor devices or glass-sealed semiconductor devices.

[Brief explanation of the drawing]

FIG. 1 is a front view of a semiconductor device according to an embodiment of the present invention, FIG. 2 is a plan view, FIG. 3 is a side view, and FIG. FIG. 5 is a plan view of the sub-lead frame constituting the lead frame, FIG. FIGS. 8(a) and 8(b) are schematic diagrams of a semiconductor device according to an example, and FIGS. 8(a) and 8(b) are a front view and a plan view of a semiconductor device according to another embodiment. FIG. The schematic plan view shown in FIGS. 10(a) and 10(b) are a front view and a plan view of a semiconductor device according to another embodiment. 1... Semiconductor device, 2... Resin package, 3.
・・Lead, 4・Lead frame, 5, 6・Sub-lead frame, 7, 8・Disastrous・Frame frame, 9. lO・
...Connection part, 11...Tab, 12...Tab suspension lead, 13...Tie bar, 14...Dam, 15...
Semiconductor element (chip), 16... wire connection part, 17
...Wire, 18...Tie bar, 19...Dam,
20...Wire connection part. Figure 3

Claims (1)

[Claims] 1. A semiconductor device having a package and a plurality of leads extending inside and outside the package, the leads being arranged in two stages in a staggered manner inside and outside the package. A semiconductor device characterized by being arranged in. 2. The semiconductor device according to claim 1, wherein inner end portions of the leads are located on the same plane. 3. A lead frame included in a part of a lead frame extending inside and outside of a package in a semiconductor device, the lead frame consisting of two sub-lead frames that are overlapped and integrated with each other. A lead frame characterized in that the leads of each sub-lead frame are located above or below the leads of other sub-lead frames, and the leads of the lead frame are arranged in two stages in a staggered manner. 4. The third aspect of the present invention is characterized in that the inner end portions of the leads of the lead frame are located on the same plane.
Lead frame as described in section.