JPS6236301Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a package that houses a semiconductor device.

A package P that houses a semiconductor element constituting an integrated circuit (IC, LSI, etc.) and is equipped with a plurality of leads for connecting and leading out each electrode of the semiconductor element.
As illustrated in FIG. 1, a semiconductor element S is housed in a cavity F formed approximately at the center of a ceramic body C having electrical insulation properties, and an external A structure in which the leads L are arranged on both sides of the ceramic body C is often used.

The plurality of external leads L, which are attached by soldering to both sides of the ceramic body C in this way, are connected to each other by the connecting leads T until the semiconductor device is completed and subjected to a conduction test. After that, it becomes independent as an external lead L and functions as a semiconductor device only after it is cut near the X--X line. As described above, the lead frame consisting of the external leads L and the connecting leads T connecting these leads is formed by stamping and integrally molding a single metal plate using a predetermined mold.

In the process of manufacturing semiconductor devices such as ICs and LSIs using such packages, there are several reasons why each external lead L is left integrally connected with the connecting lead T until it undergoes a conduction test. Place the external leads L one by one in the specified position,
It is very troublesome and inefficient to make row joints at intervals. However, if the external leads L are attached to a lead frame in which they are accurately arranged at predetermined intervals, it becomes possible to connect many external leads L at once, and it is possible to connect the external leads L and cavity F during the package manufacturing process. When applying nickel plating or gold plating as a surface treatment to the bottom of the package, it is important to note that if all the plated parts are electrically connected, you only need to connect the current-carrying terminal to one place, and when transporting the package. The main reason is that inconveniences such as the spacing of the external leads L being out of alignment or bending are less likely to occur during the manufacturing process of the semiconductor device, such as housing the semiconductor element S in a package and connecting the wires.

However, in a lead frame in which the external lead L and the connecting lead T are integrally formed in this way, the connecting lead T, which is provided for the purpose of facilitating the positioning of brazing joints, is extended during the package manufacturing process. Since the end surface of the extended end portion Ta, which is the cut portion, is usually cut at right angles to the lower surface Tb, the lower end of the extended end portion Ta is normally cut at right angles to the lower surface Tb. The corner Tc, which is created by cutting the material at a right angle, gets caught on a part of the assembly line or has a sharp corner, which prevents smooth flow movement.
Especially recently, almost all processes have been automated,
Due to the fast-moving flow during manufacturing, even the slightest corner can be adversely affected, leading to assembly line stoppages or, in some cases, product defects due to line flow defects. It was hot too.

In view of the above, the present invention aims to provide a package for semiconductor devices having a lead frame shaped so that problems such as lead frames getting caught or poor flow do not occur on an assembly line or the like.

To explain the embodiments of the present invention in detail with reference to the drawings, FIGS. 2A and 2B are partially enlarged views of only the lead frame in FIG. Extended end in Figure 1
A rounded circular portion M is formed at the lower end corner portion (corresponding to Ta) or at the lower end corner portion in the case where the extended end portion Ta is not provided. If the roundness of the circular portion M is too small, it becomes angular and nearly right-angled, and does not have a significant effect to achieve the intended purpose of the present invention. In other words, it has been found through experiments that if the circular portion M is less than 0.1R, sufficient smoothness during movement is not achieved. The experimental method involved sliding down each package cage with a lead frame with various rounded corners from a 20° slope with a constant surface condition similar to an automatic assembly line. When the roundness of the circular portion M is 0.1R or more, the results show that there is no significant difference, and the sliding properties are almost the same and relatively good.

However, such an experiment merely involves sliding down a slope, and is not equivalent to the flow movement conditions on an assembly line for manufacturing actual semiconductor devices. It was confirmed that the flow movement characteristics of the package were greatly improved by giving it a rounded shape. The present invention can be applied not only to the type of package shown in Figure 1, but also to dip-type packages in which the lead frame is welded to glass, or packages in which the lead frame is molded with synthetic resin. Needless to say, it can also be applied as is.

As described above, according to the semiconductor device package of the present invention, when the semiconductor device is completed, the external leads are not independent, but the corner portions are rounded when the connecting leads are integrated. It is possible to achieve smooth flow movement on an automatic assembly line for semiconductor devices, etc., which has many effects such as improved productivity and the ability to manufacture semiconductor devices with stable quality.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a conventional package for semiconductor devices, and FIGS. 2A and 2B are partially enlarged views of only the lead frame constituting the package for semiconductor devices according to an embodiment of the present invention. P...Package, L...External lead, T...
Articulating lead.

Claims (1)

[Scope of utility model registration request] In a semiconductor device package that houses a semiconductor device and is equipped with a plurality of external leads connected to the electrodes of the semiconductor device, the end portion of a lead frame has a connecting lead integrally formed to connect the external leads. A package for semiconductor devices characterized by rounded corners of 0.1R or more.