JPH0547837A - Mounting structure of tab type semiconductor device on lead frame - Google Patents

Abstract

PURPOSE:To obtain a narrow pitch, multi-lead TAB type semiconductor device by mounting a semiconductor element connected to a carrier film on a lead frame. CONSTITUTION:Positioning of a lead frame 2 and a bump 13c is facilitated at the time of jointing by providing a hole part 2c on a lead frame 2 in the position corresponding to a bump 13c by means of a press or the like. Further, when the surfaces of the bump 13c and the lead frame 2 are plated with tin or an alloy of tin and lead and the bump 13c is positioned to this hole part 2c so as to join both of them, a fillet 9 is formed around the bump 13c at the time of thermocompression bonding so that junction strength of both of them can be further increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure of a TAB type semiconductor device on a lead frame, and more particularly to improvement of the lead frame.

[0002]

2. Description of the Related Art Recently, electronic devices have been remarkably miniaturized, lightened and highly functionalized, and accordingly, semiconductor devices mounted on the electronic devices are strongly required to be small, surface mount type and high density mount. Is becoming

FIG. 5A is a plan view showing an example of a conventional semiconductor device (hereinafter referred to as QFP) in which leads are provided on four sides of a package, and FIG. 5B is a sectional view taken along line BB. In the figure, 1 is a semiconductor element, 2 is a lead formed on a lead frame corresponding to the electrode of the semiconductor element 1,
Hereinafter, the side connected to the semiconductor element 1 is the inner lead 2a,
The opposite side may be called outer lead 2b. Three
Is a wire made of gold, aluminum or the like, which connects the electrode of the semiconductor element 1 and the lead 3 corresponding thereto.
Reference numeral 4 denotes a package in which the semiconductor element 1, the inner leads 2a and the wires 3 are sealed. Such a semiconductor device has the semiconductor element 1 in the device hole of the lead frame.
And the electrodes 2 of the semiconductor element 1 and the corresponding leads 2 are respectively connected to the wires 3 by using a bonding tool.
Connect with. Then, in order to prevent the deterioration of each of these elements, the package 4 is made of epoxy resin or the like, each lead 2 is separated from the lead frame by a required length, and forming is performed as shown in b.

[0004]

As described above, there is an increasing demand for miniaturization and high-density mounting of semiconductor devices, and in the above QFP type semiconductor device, the number of leads has already exceeded 200 at present. The trend is for higher density. However, the pitch P of the inner leads 2a of the lead frame is limited to about twice the plate thickness t, that is, P.apprxeq.2t due to the etching capability, and it is difficult to make the pitch finer due to such restrictions. On the other hand, the number of the inner leads 2a can be increased to some extent by widening the distance between the electrodes of the semiconductor element 1 and the tips of the inner leads 2a. For this purpose, the wire 3 must be lengthened. However, if the wire is lengthened, it may come into contact with the adjacent wire 3 to cause a short circuit, or the package 4 may fall over, so that the length of the wire 3 is generally 2.5 m.
It is about m.

As described above, in the conventional semiconductor device of the wire bonding type using the lead frame, there is a technical limitation in the pitch of the leads and the length of the wires, and it is impossible to increase the number of leads any more. It was difficult.

The present invention has been made to solve the above problems, and by mounting a semiconductor element connected to a carrier film on a lead frame, a lead frame of a TAB semiconductor device having a narrow pitch and multiple leads can be formed. The purpose is to obtain a mounting structure.

[0007]

A semiconductor device according to the present invention includes a TAB type semiconductor device in which inner leads of a circuit pattern formed on an insulating film are respectively connected to electrodes of a semiconductor element and the outer shape is cut, and a large number of leads. And a lead frame having a resin, and the outer leads of the circuit pattern of the TAB type semiconductor device are connected to the leads of the lead frame and sealed with resin.

Further, bumps are provided on the outer leads of the TAB type semiconductor device, and holes are provided on the leads of the lead frame so as to correspond to the bumps.

[0009]

The semiconductor element of the TAB semiconductor device is mounted in the device hole of the lead frame, each outer lead is aligned with the lead of the lead frame, and the two are aligned by thermocompression bonding with a bonding tool. Then TAB
The semiconductor device and the inner lead of the lead frame are packaged with resin or the like, and the outer lead of the lead frame is cut and formed.

When bumps are provided on the outer leads of the TAB type semiconductor device, both can be firmly connected under a low load.

Further, if holes are provided in the leads of the lead frame so as to correspond to the bumps, not only the positioning of the two becomes easy, but also the bonding strength can be further increased.

[0012]

FIG. 1 is a diagram showing an embodiment of the present invention.

In the figure, 10 is a semiconductor device (hereinafter referred to as a TAB type semiconductor device) in which a semiconductor element 1 is connected to an inner lead of a circuit pattern provided on a carrier film. As shown in FIG. 4A, the TAB type semiconductor device 10 is made of a polyimide film or the like and is long (for example, 3 mm) provided with a large number of device holes 12 at predetermined intervals.
(00 m) carrier film 11 is formed with a large number of circuit patterns 13 made of copper foil or the like for each device hole 12 and one end thereof is projected into the device hole 12 to form an inner lead 13a. And the device hole 12
The semiconductor element 1 is arranged on the substrate, the inner leads 13a are connected to the respective electrodes by a bonding tool, and the circuit pattern is cut at the position of the cutting position (dotted line) 14. This state is shown in FIG. The surface of the circuit pattern 13 is plated with gold, for example. 15
Is a test pad, and 16 is a sprocket hole for carrying the carrier film 11.

Reference numeral 2 is a lead of a lead frame (hereinafter simply referred to as a lead frame), the upper surface of which is plated with silver. 4 is a package sealed with an epoxy resin, for example.

To mount the TAB type semiconductor device 10 as described above on the lead frame 2, the semiconductor element 1 of the TAB type semiconductor device 10 is placed in the device hole of the lead frame.
1 with the active surface thereof facing upward, and as shown in FIG. 1B, the gold plating provided on the outer lead 13b and the silver plating provided on the lead frame 2 are melted by the bonding tool 5 having a built-in heater. However, both are firmly thermocompression bonded.

When the outer leads 13b and the lead frame 2 are joined together, the semiconductor element 1, the carrier film 11 including the circuit pattern 13, and the inner leads 2a of the lead frame are sealed with, for example, epoxy resin to form the package 4. Then, if the outer lead 2b of the lead 2 is cut and formed, the manufacturing of the semiconductor device is completed.

2A and 2B show essential parts of an embodiment of the present invention. FIG. 2A is a side view, FIG. 2B is a plan view, and FIG.
(C) is an operation explanatory view. In this embodiment, bumps 13c are formed on the lower surface of the outer leads 13b of the TAB type semiconductor device 10 by, for example, half etching, and the surface thereof is plated with gold, for example.

By configuring the outer lead 13b as described above, the contact area between the outer lead 13b and the lead frame 2 can be reduced, so that both can be thermocompression bonded with a low load. Further, the hole 2 is formed on the lead frame 2 at a position corresponding to the bump 13c by pressing or the like.
By providing c, the lead frame 2 and the bump 13c
It is possible to facilitate the alignment with and to join.

Then, the surfaces of the bumps 13c and the lead frame 2 are plated with tin or an alloy of tin and lead, the bumps 13c are aligned with the holes 2c, and the two are joined together. ) Bump 13
Since the fillet 9 is formed around c, the joint strength between the two can be further increased.

FIG. 3 is a sectional view of another embodiment of the present invention. In this embodiment, the semiconductor element 1 of the TAB semiconductor device 10 is used.
Is connected to the lead frame 2 with its active surface facing down. In the case of mounting in this way, the gold plating or the like provided on the lead 13 or the bump 13c is
Is formed on the upper surface side of.

With this structure, the lead 1
The position of the lead frame 3 and the lead frame 2 can be easily aligned, and the bonding strength can be further increased.

[0022]

As is apparent from the above description, the present invention does not use a wire, and is capable of achieving a narrow pitch and multiple leads.
Since the outer lead of the AB type semiconductor device is connected to the lead of the lead frame, the distance between the semiconductor element and the tip of the lead of the lead frame can be widened, so that the number of leads can be increased. .. Further, since no wire is used, a short circuit accident will not occur even if the pitch is reduced. Further, since the TAB type semiconductor device is used, the characteristic test of the semiconductor element is easy.

Further, bumps are provided on the outer leads of the TAB type semiconductor device, holes are provided on the leads of the lead frame corresponding to the bumps, and plating is provided on the leads of the lead frame, so that they are joined together under a low load. It is possible to achieve the above, and further, the positioning is easy, and the bonding strength can be increased.

[Brief description of drawings]

1A and 1B are diagrams showing an embodiment of the present invention.

FIG. 2A to FIG. 2C are diagrams showing a main part of an embodiment of the present invention.

FIG. 3 is a sectional view showing another embodiment of the present invention.

FIG. 4A is a plan view showing a TAB semiconductor device. (B) AA sectional drawing of a TAB type semiconductor device.

FIG. 5A is a plan view showing a conventional semiconductor device. (B) BB sectional drawing of the conventional semiconductor device.

[Explanation of symbols]

 1 semiconductor element 2 lead frame 2a inner lead 2b outer lead 2c outer lead hole 3 wire 4 package 5 bonding tool 9 fillet 10 TAB semiconductor device 11 carrier film 12 device hole 13 circuit pattern 13a inner lead 13b outer lead 13c bump 14 cutting Position 15 Test pad 16 Sprocket hole

Claims (1)

[Claims] 1. A TAB semiconductor device comprising a TAB semiconductor device in which inner leads of a circuit pattern formed on an insulating film are respectively connected to electrodes of a semiconductor element and the outer shape is cut, and a lead frame having a large number of leads. A bump is formed on the outer lead of the circuit pattern of the device, a hole is formed at a position corresponding to the bump of the lead of the lead frame, and the hole of the lead of the lead frame is plated to be connected to each other. A mounting structure for a lead frame of a TAB type semiconductor device, which is characterized by being then sealed with resin.