JPH02228057A - Semiconductor device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a semiconductor device, and particularly to a multi-pin resin-sealed semiconductor device.

[Conventional technology]

FIG. 3 is a perspective plan view showing the structure of a conventional multi-bin resin-sealed semiconductor device. In this figure, (1) is a tab for mounting a semiconductor element, +21 is a semiconductor element bonded to this tab, and (3) is an electrode of this semiconductor element, which is arranged in plural along the periphery of the element. There is. (4) is a plurality of leads disposed around the semiconductor element in correspondence with the electrodes (3), and when resin encapsulation (described later) is performed, internal leads (5) located within the resin; It is composed of an external lead (6) located outside the resin. (7) is a wire such as a gold wire that connects the tip of 51 and the electrode (3), ts+ is a resin package body, which is connected to the semiconductor element), tab (1), and wire (7). ) and internal leads ((5)).

In the conventional semiconductor device constructed in this way, the tab (1) and the lead (4) are constructed as a well-known lead frame, and are processed by a stamping method or an etching method.

FIG. 4 shows an enlarged view of a part of such a lead frame, and P in the figure indicates the pitch of the inner end portions of the leads (A). When processing this type of lead frame, the processing limit value is about P = 0.24 mm for the stamping method and P = 0.21011 for the etching method when the lead frame thickness is 0.15 + am, and the value of P is If it is less than this, the punch may be damaged or it will not be possible to secure the lead width necessary for wire connection.

[Problem to be solved by the invention]

As semiconductor devices become more sophisticated, lead frames also become more sophisticated.
There is a growing demand for extremely large numbers of bins exceeding 0 bins, but in such cases, if the pitch P of the inner end of the leads is made equal to or greater than the processing limit value described above, the internal lead f5
Since the tip of the semiconductor element (2) must be located away from the semiconductor element (2), assembly work is difficult. On the other hand, in order to set the tips of the internal leads (5) at predetermined positions so as not to interfere with the assembly work, there is a problem in that the pitch P must be made smaller than the processing limit value of the frame. Note that the processing limit value can be reduced by reducing the thickness of the lead (A), but the external lead (6)
As a countermeasure to this problem, it has been proposed, for example, in Japanese Patent Publication No. 49-47590, to make only the inner end of the lead (4) thinner. This type of thin part can be easily processed by photoetching, but as shown in FIG. 5, which shows an enlarged view of the inner end of the internal lead (5), the thin processed surface (9) is rough. In this case, it is not possible to bond and secure the wire (2) for connecting to the electrode (3) of the semiconductor element to this part. In this case, as shown in FIG. There is also a method of joining the wire port to the flat surface side of the back side of the internal lead (9), but when a force is applied to the flat surface QOI of the internal lead (9) during joining, the thin part bends downward as shown in the figure. There is a problem that the joint of the wire (2) becomes unstable.

The present invention has been made to solve these problems, and it is an object of the present invention to provide a semiconductor device in which a wire can be accurately bonded and fixed to a lead having a thinner inner end.

[Means to solve the problem]

In the semiconductor device according to the present invention, the inner ends of the leads are made thinner by etching, and the etched surfaces of the thinner parts are flattened by correction processing.

[For production]

According to this invention, since the etched surface of the thin portion at the inner end of the lead is flattened, the wire can be easily bonded and fixed to this surface.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a plan view showing the inner end of several internal leads (9), and FIG. 2 is an enlarged perspective view showing the inner end of one internal lead +51.
5) is an internal lead, and (9) is a thin portion provided at the inner end of the internal lead, which is formed by photo-etching one side. (11) is a straightened surface formed by applying straightening processing such as pounding to the tip of the etched surface of the thin part.While the etched surface is a rough surface, the straightened surface (11) is It becomes a flat surface, and it is easy to bond and fix the wire (7).

〔Effect of the invention〕

As described above, according to the present invention, a thin part is formed at the inner end of the lead by etching, and the etched surface of the thin part is flattened by correction processing, making it possible to bond and fix the wire, which limits the processing limit of the frame. The value can be made small, and it is possible to cope with an extremely large number of pins.

[Brief explanation of the drawing]

Fig. 1 is a plan view of the inner end of a lead showing an embodiment of the present invention, Fig. 2 is an enlarged perspective view showing the structure of the inner end of one lead, and Fig. 3 is a conventional multi-bin resin seal. FIG. 4 is an enlarged explanatory view showing the structure of a lead frame in a conventional semiconductor device, and FIGS. 5 and 6 show the inner ends of leads in a conventional semiconductor device. FIG. In the figure, (1) is a tab, (2) is a semiconductor element, B) is an electrode, (A) is a lead, +51 is an internal lead, (6) is an external lead, the opening is a wire, 0131 is the package body,
(9) is the thin part, and (l!) is the straightened surface. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] a tab equipped with a semiconductor element having a plurality of electrodes;
A plurality of leads are arranged around the tab in correspondence with the electrodes and connected to the electrodes, and a resin package body includes a portion of the leads and seals the semiconductor element and the tab. 2. A semiconductor device comprising: an inner end portion of each lead formed by etching to be thinner than the other portion; and a straightening process such that the surface of the thin portion is flattened.