JPS61133650A - Semiconductor lead frame - Google Patents

Abstract

PURPOSE:To make the adhesion of an inner lead and a molding resin excellent, by providing bent pieces at the inner lead at a right angle with respect to the slipping-out direction of the inner lead. CONSTITUTION:A bed part 21 is supported by a suspending pin part 22. The tip parts of a plurality of inner leads 23 are arranged around the bed part 21 so as to face the part 21. An expanded part 24 is provided at the tip part of each inner lead 23a, which faces the long side part of the bed part 21. The end surface of the expanded part 24 is bent at a right angle with respect to the lead surface, and a bent piece 25 is formed.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to improvements in resin-sealed semiconductor lead frames used in the manufacture of semiconductor devices [Technical background of the invention and problems thereof] During the manufacturing process, the semiconductor chip on which the element was formed was fixed to the bed part 12 of the semiconductor lead frame 1 as shown in FIG. 2, and its electrodes and inner leads 13 were connected by bonding wires. rear,
Sealing is performed by mold resin 14 as shown by the dashed line.

Incidentally, in recent lead frames, particularly memory-related lead frames, the bed portion 12 tends to become larger as the memory element becomes larger.

Therefore, in the conventional lead frame 11, especially the inner leads 13h facing the long sides of the bed portion 12,
13h..., the inner lead 13a is from the end surface A of the molded resin 14.

13h... Distance to each tip 15 (L in the figure)
(shown by ) becomes very short to 75. That is, the length of the inner leads 13h, 13a, . . . themselves becomes short, and therefore, there is a drawback that a large area of contact with the mold resin 14 cannot be secured.

If a large area of contact with the mold resin 14 cannot be obtained in this way, the process of cutting the dam part 17 of the outer lead 16
Or, the inner leads 13a813, a... may become loose due to tensile force generated during the bending process, etc.
It may even fall out.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to provide a semiconductor lead frame in which inner leads do not wobble or come off even when tensile force is generated during the cutting process of outer leads. It is in.

[Summary of the invention]

The present invention provides a semiconductor lead frame in which a semiconductor chip is fixed to a bed portion, and after bonding wiring between an electrode of the chip and an inner lead portion is sealed with a resin, one of the inner leads is sealed with a resin. A widened portion is provided at a portion of the inner lead facing the bed portion that is vulnerable to tensile force, and a portion of this widened portion that does not come close to the dending is bent approximately at right angles to the lead surface. This bent portion increases the resistance to the lead tensile force.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. In Fig. 1, reference numeral 2 is a bed section supported by a hanging shim section 22, and the tips of a plurality of inner leads 23, 23, . . . are disposed facing each other around the bed section 2. ing. Among these inner leads 23, widened portions 24 are provided at the tip portions of each of the inner leads 23a, 23a facing the long side portions of the bed portion 21.

The end surface of the widened portion 24 on the side opposite to the bed, which does not contribute to bonding, is bent at right angles to the lead surface to form bent pieces 25, 25, . . . . These folded pieces 2
5.25... may be formed during the transportation process of the lead frame before the mounting process, or may be formed simultaneously during press molding of the lead frame itself.

As described above, in the lead frame of the present invention, since the inner leads 23a, 23h... are provided with bent pieces 25, 25... at right angles to the direction of removal,
The adhesive area with the mold resin 26 becomes larger, and therefore the resistance to tension becomes larger. Therefore, even if tensile force is generated during the cutting process of the dam part 27 or the bending process of the outer leads 28, 28, etc. after sealing with the mold resin 26, the inner leads 2B, 23, etc.・
・The occurrence of wobble and slippage is reduced.

〔Effect of the invention〕

As described above, according to the present invention, the adhesion between the inner lead and the mode resin is increased, so even if tensile force is generated during the cutting process of the dam part, the inner lead does not come off or wobble. This makes it possible to improve product yield.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the structure of a semiconductor lead frame according to an embodiment of the present invention, and FIG. 2 is a perspective view showing the structure of a conventional semiconductor lead frame. 21... Bed part, 23. 23a... Inner lead, 24... Widening part, 25... Bending piece, 26...
mold resin. Applicant's agent Patent attorney Takehiko Suzue 61

Claims (1)

[Claims] In a semiconductor lead frame in which a semiconductor chip is fixed to a bed part, bonding wiring is made between the electrode of the chip and the inner lead part, and then resin-sealed, a part of the inner lead that is weak against tensile force A widened part is provided in a part of the inner lead facing the bed part,
A semiconductor lead frame characterized in that a portion of the widened portion that does not contribute to the bonding is bent substantially at right angles to the lead surface.