JPH0714973A - Lead frame for semiconductor device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a lead frame for a semiconductor device capable of effectively disposing inner leads around a tab of a lead frame and preventing a reduction in the yield of wire bonding. To aim. [Structure] A rectangular tab b for supporting a semiconductor element a,
A plurality of inner leads c for wire connection, one end of which is provided close to the tab b, a quadrangular frame portion d which supports the inner leads c at the other ends of the inner leads c, and the tab b
In a lead frame f for a semiconductor device having a suspension lead e for supporting a tab extending from the frame portion d to the frame portion d, the tab b is formed in a substantially square shape, and the frame portion d is formed in a substantially rectangular shape. Is arranged substantially in the center of the frame portion d,
The tab supporting suspension lead e is arranged on a diagonal line connecting the four corners of the frame portion d.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device, and more particularly to a lead frame used for a resin-sealed semiconductor device.

[0002]

2. Description of the Related Art Conventionally, as a lead frame used in this type of resin-sealed semiconductor device, for example, there is one shown in FIG. This lead frame 100 is
As is well known, a plurality of lead frames corresponding to a plurality of semiconductor devices are connected in a strip shape so that a plurality of semiconductor devices can be manufactured by a series of manufacturing processes.

The lead frame 100 is a lead frame for a rectangular quad flat package (QFP). As shown in FIG. 3, the lead frame 100 has wide outer portions arranged on both sides thereof in parallel with each other. Frames 101, 101, dams 103, 103 connected to these outer frames 101, 101 to partition a rectangular region corresponding to the resin sealing portion 102 of the semiconductor device, and the dams 103, 103 at the center of the dams 103, 103. Arranged semiconductor element 104
A flat square tab 105 for supporting the inner surface of the semiconductor element 104, a plurality of inner leads 106 that are connected to the terminals of the semiconductor element 104 by wire bonding (not shown), and these inner leads 106 are linearly connected to each other via the dam 103. The outer lead 107 to be provided is integrally provided. In the lead frame 100, the semiconductor element 104 is placed on the central tab 105, and the terminals of the semiconductor element 104 and the tips of the inner leads 106 are connected to each other by wire bonding. A region 102 surrounded by a one-dot chain line corresponding to the inside of 103, 103 is sealed with resin.

As described above, the lead frame 100
Includes a tab 105 for supporting the semiconductor element 104 mounted thereon when the resin is injected. The tab 105 is three or more (four in the illustrated example) so as not to be displaced by the resin and dislocated. The suspension leads 108 are supported and fixed to the dams 103 of the lead frame 100. In particular, in the case of the lead frame 100 for the quat flat package in which the inner leads 106 are arranged in four directions on the outer periphery of the tab 105 described above, the number of the inner leads 106 is increased, so that a portion where the leads 106 are not arranged, that is, Tab 1 formed in a flat square shape
Dam 10 formed in a rectangular shape from four corners of 05
The suspension leads 108 are provided toward the four corners 3 and 103.

The tab 1 of the lead frame 100 is also used.
The shape of the semiconductor element 104 mounted on the substrate 05 is such that the peripheral length per unit area is short and the cutting line on the semiconductor wafer is shortest.
It is set in a square that can take the most.

[0006]

However, the above-mentioned prior art has the following problems. That is, in the case of a semiconductor device in which the square semiconductor element 104 is mounted on the rectangular quad flat package lead frame 100 as described above, the outer lead 107 outside the resin sealing portion 102 is The rectangular dams 103, 103 can be evenly arranged according to the length of the short side and the long side. However, the resin sealing portion 10
The inner lead 106 in 2 has four tabs 105 on which the semiconductor element 104 is mounted, which connects the four corners of the square tab 105 and the four corners of the rectangular dams 103, 103. The inner leads 10 per length in the vicinity of the tab 105 on the short side and the long side of the dams 103 are divided by the suspension leads 108.
The number of 6 will be different. Therefore, in the case of the lead frame 100, it is necessary to narrow the lead pitch on the long side of the tab 105 or separate the tip position of the inner lead 106 on the long side from the tab 105, and perform wire bonding. At this time, there is a problem that the movement pitch and the movement distance of the tip of the wire bonding machine are not constant, wire bonding defects easily occur, and the yield of wire bonding on the long side of the tab 105 is reduced.

Therefore, the present invention has been made to solve the above-mentioned problems of the prior art. The purpose of the present invention is to effectively dispose inner leads around the tabs of the lead frame. An object of the present invention is to provide a lead frame for a semiconductor device capable of preventing the yield of wire bonding from decreasing.

[0008]

That is, the present invention is
As shown in FIG. 1, a quadrangular tab b for supporting the semiconductor element a, a plurality of inner leads c for wire connection, one end of which is provided close to the tab b, and the other ends of the inner leads c. And a quadrangular frame portion d for supporting them, and a tab supporting suspension lead e extending from the tab b to the frame portion d.
In the lead frame f for a semiconductor device having, the tab b is formed in a substantially square shape, the frame portion d is formed in a substantially rectangular shape, and the tab b is arranged substantially in the center of the frame portion d. The suspension lead e for the
It is configured to be arranged on a diagonal line connecting the two corners.

The suspension lead for supporting the tab is, for example,
Four are arranged at the positions corresponding to the four corners of the frame,
The number is not limited to this, and may be about three.

[0010]

In the present invention, the tab is formed in a substantially square shape, the frame portion is formed in a substantially rectangular shape, the tab is arranged substantially in the center of the frame portion, and the suspension lead for supporting the tab is
Since it is arranged on a diagonal line connecting the four corners of the frame part, it is divided by the ratio of the vertical and horizontal sides of the frame part formed in a substantially rectangular shape and the suspension leads for supporting the tabs. The length ratio between the vertical and horizontal areas of the tab can be made equal, and multiple inner leads can be evenly arranged around the tab. The movement pitch and the movement distance of the tip of the bonding machine become constant, and it is possible to prevent the occurrence of defective wire bonding, and it is possible to prevent the yield of wire bonding from decreasing.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to illustrated embodiments.

FIG. 2 shows an embodiment of a lead frame for a semiconductor device according to the present invention.

In FIG. 2, reference numeral 1 indicates a lead frame for a rectangular quat flat package.
As is well known, the lead frame 1 has a plurality of lead frames corresponding to the plurality of semiconductor devices connected in a strip shape so that the plurality of semiconductor devices can be manufactured by a series of manufacturing steps.

As shown in FIG. 2, the lead frame 1 has a wide strip-shaped outer frame 2 located at both ends in the width direction.
An outer frame 3 formed so as to connect these outer frames 2 to each other, and a rectangular region corresponding to the resin sealing portion 4 of the semiconductor device, which is connected to the outer frames 2 and 3, is defined. Dams 5 and 6 as frame parts, tabs 11 having a square shape in a plane for supporting the semiconductor element 7 arranged in the center of these dams 5 and 6, and terminals of the semiconductor element 7 and wire bonding (not shown) A plurality of inner leads 9 to be connected and an outer lead 10 linearly connected via the inner leads 9 and dams 5 and 6 are integrally provided.

In the lead frame 1, the semiconductor element 7 is placed on the central tab 11 and the semiconductor element 7 is mounted.
The terminal 5 and the tip of the inner lead 9 are connected by wire bonding,
The resin sealing portion 4 corresponding to the inside of 6 is sealed with resin.

The semiconductor element 7 mounted on the tab 8 of the lead frame 1 has a short perimeter per unit area and the shortest cutting line on the semiconductor wafer.
That is, the square is set so that the largest number of semiconductor elements 7 can be taken from the semiconductor wafer.

As described above, in the lead frame 1, the tabs 11 for supporting the semiconductor element 7 mounted thereon during resin injection are formed in a square shape corresponding to the shape of the semiconductor element 7, and the frame portion is also formed. The dams 5 and 6 are formed in a rectangular shape according to the shape of the resin sealing portion 4. In addition, one end of each of the plurality of inner leads 9 has a tab 11
And the other ends are connected to the long sides and the short sides of the dams 5 and 6 at equal intervals, and the inner leads 9 of these are
It is formed so as to extend in four directions from the vicinity of each of the four sides of the tab 11 toward the corresponding sides of the dams 5 and 6.

By the way, in this embodiment, the leads for supporting the tabs are arranged on a diagonal line connecting the four corners of the frame. That is, the four suspension leads 15 for supporting the tabs are arranged on the diagonal lines connecting the corners 16 of the rectangular dams 5 and 6 and connecting the corners 16, and the tab 11 has a rectangular shape. It is arranged in the center of the dams 5 and 6, and the tab 11 and the suspension lead 15 are connected at a position displaced from the corner of the square tab 11 to the short side of the resin sealing portion 4.

In the lead frame for the semiconductor device according to this embodiment having the above-mentioned structure, the inner leads can be effectively arranged around the tabs of the lead frame as follows, and the yield of wire bonding is lowered. It is designed to prevent you from doing so.

That is, the lead frame 1 is shown in FIG.
2, the tab 11 is formed in a square shape, and the dams 5 and 6 are formed in a substantially rectangular shape. The tab 11 is arranged in the center of the dams 5 and 6, and the suspension lead for supporting the tab is provided. 15 is arranged on a diagonal line connecting the four corners 16 of the dams 5 and 6. Therefore, in the lead frame 1, the ratio of the long side to the short side of the dams 5 and 6 formed in a rectangular shape, the vertical area of the tab 11 defined by the suspension lead 15 for supporting the tab, and the lateral direction of the tab 11 are defined. The ratio of the lengths of the regions can be made equal, and the plurality of inner leads 9 can be evenly arranged around the tab 11. Therefore, when performing the wire bonding, it is possible to prevent the movement pitch and the movement distance of the tip of the wire bonding machine from becoming constant, and it is possible to prevent the wire bonding failure from occurring and prevent the yield of the wire bonding from decreasing. You can

[0021]

According to the present invention having the above-described structure and operation, the inner leads can be effectively arranged around the tabs of the lead frame, and the yield of wire bonding can be prevented from lowering. A lead frame can be provided.

[Brief description of drawings]

FIG. 1 is a plan configuration diagram showing a lead frame for a semiconductor device according to the present invention.

FIG. 2 is a plan view showing an embodiment of a lead frame for a semiconductor device according to the present invention.

FIG. 3 is a plan view showing an embodiment of a conventional lead frame for a semiconductor device.

[Explanation of symbols]

1 lead frame, 2, 3 outer frame, 4 resin sealing part,
5, 6 dam, 7 semiconductor element, 8 tab, 9 inner lead, 10 outer lead, 11 tab, 15
Hanging leads.

Claims (1)

[Claims] 1. A quadrangular tab for supporting a semiconductor device,
A plurality of inner leads for wire connection, one end of which is provided close to the tab, a rectangular frame portion which supports the inner leads at the other end thereof, and a tab supporting portion which extends from the tab to the frame portion. In a lead frame for a semiconductor device having a suspension lead of, the tab is formed in a substantially square shape, the frame portion is formed in a substantially rectangular shape, and the tab is arranged at a substantially central portion of the frame portion for supporting the tab. The lead frame for a semiconductor device, wherein the suspension lead is arranged on a diagonal line connecting four corners of the frame.