JPH03219663A - Lead frame for semiconductor device - Google Patents

Abstract

PURPOSE:To increase the wire bonding point of an inner lead and to prevent a malfunction of removal of the wire from the lead by so providing two or more rows of positions of the points of the leads that distances from the outer periphery of a die pad are alternately different. CONSTITUTION:The positions of wire bonding points 9 are so disposed that distances from the outer periphery of a die pad 2 are alternately different. Since the adjacent points are far from one another, the width of the point 9 of an inner lead 1a can be increased, and a wire bonding can be stably conducted. The improvement in the stability of the thus obtained bonding causes improvements in the assembling yield of a semiconductor device and in quality, reliability of a multipin semiconductor device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the shape of a lead frame for a semiconductor device used in the assembly process of a semiconductor device.

(Prior Art) In a semiconductor device, a bonding pad of a semiconductor element formed from an integrated circuit is connected to each lead of a corresponding lead frame, and then the inner part of each lead other than the outer tip is formed by transfer molding or the like. It is integrally molded with resin. Then, each lead is cut on the outside of the molded resin, and the semiconductor device is assembled by appropriately bending the leads as necessary. FIG. 4 is a perspective view showing an example of a completed conventional semiconductor device. In FIG. A wire 5 connecting the element 3 and the corresponding lead 1 is a sealing resin that integrally molds the semiconductor element 3 and the like. In particular, in the lead 1, the portion buried inside the resin 5 will be referred to as an inner lead la, and the portion extending outside the sealing resin 5 will be referred to as an outer lead 1b.

In actual semiconductor device assembly work, the die pad 2 and leads 1 are connected by a dam bar 6 as shown in FIG. The second detailed view of the die pad 2 and inner lead 1a on which the semiconductor device r is mounted in the lead frame shown in FIG. 3, which is called a lead frame.
It is a diagram.

It is generally known that the inner lead portion of a conventional lead frame has a shape in which the wire bonding points 9 of the inner lead 1a are arranged in a line at approximately the same distance from the outer periphery of the die pad 2, as shown in FIG. There is.

[Problem to be solved by the invention]

The above-mentioned semiconductor devices tend to have multiple bins due to the recent needs for higher integration and higher functionality of semiconductor elements, so the lead frames used for them are also becoming more binned and the number of leads 1 is increased to increase the packaging density. The pitch has been reduced, and not only the pitch of the outer lead 1b but also the pitch of the inner lead 1a has become finer. However, if the pitch is reduced while maintaining the conventional inner lead shape, the width of each inner lead becomes extremely narrow, making it difficult to process the lead frame, and at the same time making it difficult to wire bond when assembling semiconductor devices. Also, since the wire is bonded onto a narrow lead, even a slight positional deviation causes the wire to come off from the inner lead 1a, resulting in a wire bonding failure.

Therefore, in order to solve this problem, the present invention makes the wire bonding points 9 of the inner leads 1a of the lead frame in two or more rows in different rows, thereby increasing the width of the wire bonding points 9. This provides stable wire bonding.

[Means to solve the problem]

In order to solve the above problems, the lead frame of the present invention is characterized in that the wire-bonding points of the inner leads are arranged in two or more rows so as to be alternately different, thereby increasing the width of the wire-bonding portion of the inner leads. do.

〔Example〕

Embodiments of the present invention will be described below based on the drawings. Although the basic configuration is the same as that shown in FIG. 3, which is an example of the prior art, FIG. 1 shows a partially detailed view of an embodiment of the present invention.

In FIG. 1, 1a is an inner lead, and 2 is a die pad of a semiconductor element mounting portion. 9 is a wire bonding point of the inner lead. As a result of alternating the positions of the wire bonding points 9 at different distances from the outer periphery of the die pad 2, the adjacent wire bonding points become farther apart, so the width of the wire bonding point 9 of the inner lead 1a is increased. This is what I did.

〔Effect of the invention〕

As described above, in the lead frame of the present invention, the wire bonding points of the inner leads are arranged in two or more rows so that the distances from the outer periphery of the die pad are alternately different. can be made wider. As a result, when performing wire bonding during assembly of a semiconductor device, defects such as wires coming off from inner leads due to slight positional deviation are reduced, and wire bonding can be performed stably. The improved stability of wire bonding obtained in this manner not only improves the assembly yield of semiconductor devices but also contributes to improving the quality and reliability of multi-bin semiconductor devices.

[Brief explanation of drawings]

FIG. 1 is a partially detailed plan view showing an embodiment of the lead frame of the present invention. FIG. 2 is a partially detailed plan view showing an example of a conventional lead frame. FIG. 3 is a perspective view showing an example of a conventional lead frame. FIG. 4 is a perspective view showing an example of a conventional completed semiconductor device. 1...Lead 1a...Inner lead 1b...Outer lead 2...Die pad 3...Semiconductor element 4...Wire 5...Sealing resin 6...Dam bar 7...Strip shape Frame 9: Wire pond day pointing of inner lead or more

Claims (1)

[Claims] Consists of a rectangular band-shaped frame, a semiconductor element mounting part, a plurality of leads extending from the band-shaped frame to the vicinity of the semiconductor element mounting part, a dam bar located between the plurality of leads and connecting the plurality of leads, etc. In a lead frame for a semiconductor device, the wire bonding point of the lead (distance from the semiconductor element mounting part) is set to 2.
A lead frame for a semiconductor device, characterized in that the width of the wire bonding portion of the lead is widened by making the lead frame larger than one row.