JPH07202105A - Lead frame for semiconductor device - Google Patents

Abstract

PURPOSE:To obtain a resin-sealed semiconductor device with a structure of a stable die pad to prevent stay shift difficult by reinforcing a suspension lead. CONSTITUTION:In a semi-lead frame 10 equipped with a suspension lead 3 and the like connecting, to a stay, each corner of a plurality of inner leads 2 and a die pad 1, which are provided with an inner part arranged at a preset space along the perimeter which is at a preset space from a perimeter of the die pad 1 having a plurality of corners, each suspension lead 3 is connected by beams 6A, 6B, 6C, and 6D between the die pad 1 and each inner lead 2, and a suspension lead 2 is connected to the inner leads 2 on both sides by arms 7A and 7B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-encapsulated semiconductor device lead frame (hereinafter referred to simply as "lead frame").
In particular, the present invention relates to a reinforcing structure of a suspension lead that supports a die pad in a lead frame for a QFP type IC having a large number of pins.

[0002]

2. Description of the Related Art First, referring to FIG.
The structure of the lead frame used in the mold resin-sealed semiconductor device (hereinafter, simply referred to as “QFP type IC”) will be described. FIG. 2 is an enlarged plan view of a main part of a conventional lead frame. This lead frame 20 is provided with a quadrilateral die pad 1 in the center, and a plurality of inner leads 2 are arranged at predetermined intervals along each periphery of the four sides of the die pad 1, and are shown in the figure. Although not provided, a plurality of outer leads are connected to each of the inner leads 2.

The die pad 1 is formed in a structure in which the ends of the suspension leads 3 extending from the respective corners are connected to and supported by a stay or frame (not shown). The stay and the frame are collectively referred to as “stay” hereinafter.

The semiconductor chip 4 is fixed to the die pad 1 of the lead frame 20 having such a structure, each electrode of the semiconductor chip 4 is connected to the inner end portion of each inner lead 2 by the bonding wire 5, and then the molding die is formed. Mounted on the mold,
The semiconductor chip 4 is resin-sealed.

The illustrated lead frame 20 is a multi-pin QF.
Since it is a P type and the inner end portion of each inner lead 2 is the processing limit, it cannot be projected to the die pad 1 side. On the other hand, since the semiconductor chip 4 is reduced in size, the area of the die pad 1 is also reduced, and accordingly, the suspension lead 2 is also thin and long, and the die pad 1 is supported by such a thin and long suspension lead 2. , Must be connected to the stay.

[0006]

As described above, when the semiconductor chip is reduced in size and the number of pins is increased, the suspension lead 2 is also thin and long. Therefore, when the semiconductor chip 4 is resin-sealed with a molten resin using a molding die, there is a phenomenon that the die pad 1 is stay-shifted by the flow pressure of the molten resin when the molten resin is injected into the molding die. There was a problem that it would occur. An object of the present invention is to reduce the occurrence of stay shift of the die pad.

[0007]

Therefore, in the lead frame of the present invention, a die pad having a plurality of corners,
The die pad is provided with a predetermined distance from the peripheral edge thereof, and a plurality of inner leads having inner end portions arranged at a predetermined distance along the peripheral edge, and suspension leads for connecting the corners of the die pad to the stays. In the lead frame for a semiconductor device, between the die pad and each inner lead, the suspension leads are configured to be connected by a reinforcing member, or the suspension lead is connected to inner leads existing on both sides thereof. The above-mentioned problems were solved by using a reinforcing member for connection or by using both together.

[0008]

Therefore, the die pad is reinforced, and the stay shift due to the flow pressure of the molten resin is less likely to occur, and a good QFP type IC can be obtained.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the lead frame of the present invention will be described below with reference to FIG. FIG. 1 is an enlarged plan view of a main part of the lead frame of the present invention. The same components as those of the conventional lead frame are designated by the same reference numerals, and the description of those components will be omitted.

In FIG. 1, reference numeral 10 generally indicates a lead frame of the present invention. In this lead frame 10, between the die pad 1 and each inner lead 2, the suspension leads 2 are connected by beams 6A, 6B, 6C and 6D which are reinforcing members, and furthermore, the suspension leads 3 are also connected. Were connected to the inner leads 2 existing on both sides thereof at a plurality of positions in the lengthwise direction, that is, at two positions in this embodiment, by arms 7A and 7B which are reinforcing members.

The semiconductor chip 4 is die-bonded to the die pad 1 having such a structure with an adhesive or the like, and then each electrode of the semiconductor chip 4 and the inner end portion of the corresponding inner lead 2 are connected by a bonding wire 5. The lead frame 10 to which the semiconductor chip 4 is fixed is mounted on a transfer mold and a molten resin is injected,
By resin-sealing, a desired resin-sealed semiconductor device can be obtained.

In the lead frame 10 of the above embodiment, the beams 6A, 6B, 6C and 6D and the arms 7A and 7B are used together to reinforce the suspension lead 2 more strongly and prevent the occurrence of stay shift as much as possible. , Semiconductor chip 4
The beam and the arm may be used individually depending on the area of the die pad 1.

Although this embodiment has been described with reference to the lead frame used for the QFP type IC, when the suspension lead is reinforced only by the arms 7A and 7B, a lead frame for another type, for example, a SOP type IC is used. Can also be applied to.

[0014]

As described above, in the lead frame of the present invention, since the suspension lead is reinforced by the beam and / or the arm which is the reinforcing member, the die pad has a stable structure and the stay shift is small or the stay shift is small. It is possible to obtain a resin-sealed semiconductor device in which no shift occurs.

[Brief description of drawings]

FIG. 1 is an enlarged plan view of a main part of a lead frame for a semiconductor device according to the present invention.

FIG. 2 is an enlarged plan view of a main part of a conventional semiconductor device lead frame.

[Explanation of symbols]

 1 die pad 2 inner lead 3 suspension lead 4 semiconductor chip 5 bonding wire 6A beam 6B beam 6C beam 6D beam 7A arm 7B arm 10 lead frame of this invention

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[Procedure amendment]

[Submission date] January 7, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

The die pad 1 is formed in a structure in which the ends of the suspension leads 3 extending from the respective corners are connected to and supported by a stay or frame (not shown). In this specification,
The stay and the frame are collectively referred to as a "stay" and hereinafter simply referred to as "stay".

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

[Procedure 3]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 2

[Correction method] Change

[Correction content]

[Fig. 2]

Claims (2)

[Claims] 1. A die pad having a plurality of corners, a plurality of inner leads having a predetermined distance from a peripheral edge of the die pad, and inner end portions arranged along the peripheral edge at a predetermined distance, and the die pad. In a lead frame for a semiconductor device including a suspension lead that connects each corner to a stay, for a semiconductor device, the suspension pad is connected between the die pad and each inner lead with a reinforcing member. Lead frame. 2. A die pad having a plurality of corners, a plurality of inner leads arranged at predetermined intervals from a peripheral edge of the die pad, and arranged along the peripheral edge at a predetermined interval, and a suspension lead connecting the die pad to a stay. In a lead frame for a semiconductor device, the suspension lead is connected to inner leads existing on both sides thereof by a reinforcing member.