JPH03220740A - Structure of semiconductor device - Google Patents

Abstract

PURPOSE:To prevent positional deviation of lead and inhibit the generation of its deformation by supporting the lead in a device hole of TAB(Tape Automated Bonding) with an organic coat and making thinner the thickness of the organic coat than that of a bump electrode. CONSTITUTION:This is the structure of a semiconductor device, using TAB(Tape Automated Bonding) which comprises a polymid tape 1, a bonding agent 2, and a rolled copper foil 3, thus forming three layer structure TAB tape. In this case, a lead 4 of the rolled copper foil 3 is eutectically soldered. For example, a 5mum thick polymid 5 is adapted to adhere to the rolled copper foil 3 while an aluminum electrode 7 is laid out on the surface of a semiconductor element 6 as a connection electrode. At the same time, passivation 8 is coated on the surfaces of other components which exclude the aluminum electrode 7 as a protection film for the semiconductor element 6 at the maximum thickness of 2mum. Furthermore, a metallic bump electrode, which is 15mum high, is formed on the aluminum electrode 7, thereby providing the rolled copper foil 3 on the three layer structure TAB tape and electric and physical connections. It is, therefore, possible to eliminate positional deviation of the lead and the generation of its deformation and prevent the generation of short circuit between the lead and the semiconductor element.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of a semiconductor device, and particularly to the structure of a semiconductor device using TAB.

[Conventional technology]

Conventionally, the structure of this type of semiconductor device is TA, which consists of a three-layer structure consisting of a base tape made of organic material, adhesive, and copper foil.
The lead part of the B tape is plated with gold, tin, solder, etc., and a protruding electrode of gold, solder, etc. is provided on the electrode part of the semiconductor element to be connected, and the lead of the TAB tape and the protruding electrode are aligned. The structure was such that they were connected using thermocompression bonding.

[Problem to be solved by the invention]

The structure of the conventional semiconductor device described above has a drawback in that the leads are easily misaligned and deformed because the leads extend long into the device hole of the TAB tape.

Furthermore, since the conductor of the lead exists on the semiconductor element in an uninsulated state, there is also a drawback that an electrical short circuit is likely to occur between the lead and the semiconductor element.

SUMMARY OF THE INVENTION An object of the present invention is to provide a structure of a semiconductor device in which deformation does not occur in the positions of the wires 1 and 1, and short circuits do not occur between the wires 1 and the semiconductor element.

[Means to solve the problem]

The present invention is based on TAB (Tape Automate).
In the structure of a semiconductor device using d bonding, the base tape and the adhesive are used to connect semiconductor elements using a TAB tape consisting of a three-layer structure of a base tape made of an organic substance, an adhesive, and a copper foil. A lead made of copper foil, which extends into a device hole drilled through and is provided for connecting to the semiconductor element, is connected to the semiconductor element on the side to be connected to the semiconductor element. The TAB tape has an organic film thinner than the protrusion thickness of the protrusion electrode of the conductor provided on the connection electrode portion of the semiconductor element, and is formed on the entire surface of the device hole, except for the lead portion. The lead portion from which the organic film has been removed and the semiconductor element are connected via the protruding electrode.

In the structure of the semiconductor device described in Section 2.1, the portion where the organic film is removed in the device hole or the lead portion connected to the semiconductor element is not exposed and is connected to a mounting board on which the semiconductor device is mounted. The lead portion has also been removed.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view of a first embodiment of the invention.

In Figure 1, 1 is a 75 μm thick polyimide tape;
2 is an adhesive, and 3 is a rolled copper foil with a thickness of 35 μm, constituting a TAB tape with a three-layer structure.

Note that the leads 4 made of rolled copper foil 3 are plated with 1 μm thick eutectic solder. 5 is polyimide with a thickness of 5 μm, and is in close contact with the rolled copper foil 3. 6 is a semiconductor element,
An aluminum electrode 7 with a thickness of 1 .mu.m is arranged as a connection electrode on the surface thereof, and a passihesicon 8 is coated with a maximum thickness of 2 .mu.m on the surface other than the aluminum electrode 7 as a protective film for the semiconductor element 6. Furthermore, a height of 15μ is placed on the aluminum electrode 7.
A gold protrusion electrode 9 of m is formed, and the TA has a three-layer structure.
Electrical and physical connections are made with the rolled copper foil 3 on the B tape.

FIGS. 2(a) to 2(k) are sectional views showing the manufacturing process of the first embodiment of the present invention in order of process.

First, as shown in FIG. 2 (a), a 75 μm thick polyimide tape 1 (trade name: Upilex), which has already been coated with a 20 μm thick epoxy adhesive 2, is slit to a width of 35 mm. As shown in (b), a device 5 hole]O and a sprocket hole (not shown) were punched out using a mold.The subsequent steps were all carried out using the sprocket hole.

Next, as shown in FIG. 2(c), a rolled copper foil 3 (product name ○FC-
ACE foil) with the roughened side facing the adhesive 2, passed through a roll adjusted to 150°C and 2.5 kg/cm2, and heated to 100°C.

It was laminated by drying for 4 hours.

Next, as shown in FIG. 2(d), a photosensitive polyimide 11 (trade name: Pimel) is placed in the device hole 10 after drying.
It was applied dropwise to a thickness of 0 μm and dried in a clean open air atmosphere at 100° C. for 13 seconds.

After that, as shown in Fig. 2(e), 200 mj/cm
2, photosensitive polyimide 11 was exposed to contact light for 10 seconds, then immediately spray developed for 15 seconds, overlapped for 3 seconds, and spray rinsed for 10 seconds. After that, N
It was dried at 140° C. for 30 minutes in a clean open atmosphere of 2 atmospheres, and then at 250° C. for 11 hours.

Next, as shown in FIG. 2(f), the exposed polyimide 12 was exposed to a gas of CF 4:02 = 95:5 at a pressure of 200 mI/sec and a degree of vacuum of 0.5.
Dry etching was carried out at an output of 100 W.

After patterning the photosensitive polyimide 12, as shown in FIG.
As shown in g), TAB tape is chemically polished, acid treated,
After washing with water, resist 13 was applied on both sides and precured at 130° C. for 5 minutes.

After that, as shown in Fig. 2 (h), 300 m j /
The resist 13 on the side in close contact with the rolled copper foil 3 was exposed to contact light at cm2.

Subsequently, as shown in FIG. 2(i), the film was developed with a 1% aqueous solution of sodium carbonate and washed with water.

Thereafter, as shown in FIG. 2(j), unnecessary rolled copper foil 3 was removed by etching with 30% ferric chloride, and leads 14 were formed by washing with water and showering.

Finally, as shown in FIG. 2(k), the resist on both sides was removed with a 3% caustic soda aqueous solution, and the desired TAB tape was prepared by washing with water and showering.

On the other hand, as shown in FIG. 1, a protruding gold electrode 9 of 15 μm in height was formed by electrolytic plating on the aluminum electrode 7 of the semiconductor element 6 whose surface had been previously subjected to passivation 8 .

Therefore, the gold protrusion electrode was roughly aligned with the connection position of the TAB tape with 1 μm of Sn:Pb=60:40 solder applied to the surface of the lead 4 made of the rolled copper foil 3, and the gold protrusion Insert the electrode 9 into the hole where the polyimide 5 of the lead 4 has been removed, and heat at 250°C and 2kg/cm.
A semiconductor device structure as shown in FIG. 1 was made by thermocompression bonding for 2.1 seconds.

At this time, even if the pressing force is extremely increased, the minimum distance between the rolled copper foil 3 and the semiconductor element 5 is defined by the polyimide 4 and the passivation 8, and the stress is also alleviated, so it is not possible to use a protruding gold electrode. There was no occurrence of cracks under the aluminum electrode 7.

FIG. 3 is a sectional view of the second embodiment of the present invention, and FIG. 4 is a sectional view of the second embodiment of the present invention.
FIG. 3 is a cross-sectional view of an example of mounting the embodiment on a mounting board.

In Figure 3, 1 is a 75 μm thick polyide tape, 2
3 is an adhesive, 3 is a rolled copper foil with a thickness of 35 μm, and a 3-layer T
Forming AB tape. Note that the leads 4 made of rolled copper foil 3 are plated with 1 μm thick eutectic solder. 5 is polyimide with a thickness of 5 μm, and is in close contact with the rolled copper foil 3.

6 is a semiconductor element with a 1 μm connection electrode on its surface.
A thick aluminum electrode 7 is arranged, and a passivation 8 is coated with a maximum thickness of 2 μm on the surface other than the aluminum electrode 7 as a protective film for the semiconductor element 6. Furthermore, one protruding solder electrode with a height of 15 μm is formed on the aluminum electrode 7, and is electrically and physically connected to the rolled copper foil 3 on the three-layer TAB tape.

Note that the polyimide 5 of this example has solder protruding electrodes 19.
Place the semiconductor element 6 on the mounting board 1 other than where it fits.
The lead portion (hereinafter referred to as OLB portion) 17 that is connected to the OLB portion when mounted on the OLB portion 5 is also removed. Therefore, as shown in Figure 4, the OL
A mounting board 1 on which the semiconductor device is separated at the outer periphery of the B portion 17 and the semiconductor element 6 is mounted using the OLB portion 17.
The semiconductor element 6 of this embodiment can be thermocompression-bonded to the conductor pattern 16 of No. 5 for electrical and physical connection.

In this embodiment, even if the temperature is increased or the time is increased during thermocompression bonding of the semiconductor element 6 and the TAB tape, the solder protrusion electrodes 19 of the aluminum electrodes 7 will not flow out onto the solder wires 4. Therefore, polyimide 5 has the advantage of preventing solder from flowing.

Furthermore, as shown in FIG. 4, if a semiconductor device is mounted on the mounting board 15 without the three-layer TAB, there will be no adhesive, which causes current leakage between the leads. There is also the advantage of improved quality.

〔Effect of the invention〕

As explained above, in the present invention, most of the leads in the zero device holes of the TAB tape are supported by an organic film,
In addition, by making the thickness of the organic film thinner than the protruding electrodes on the electrodes of the semiconductor element, it is possible to prevent misalignment and deformation of the lead, and also to prevent short circuits between the lead and the semiconductor element. This also has the effect of maintaining an appropriate distance between the leads and the semiconductor element.

Furthermore, since the organic film is removed only at the connecting portion near the lead portion connected to the semiconductor element, there is an effect that alignment can be completed by simply fitting the protruding electrode of the semiconductor element.

In addition, due to the presence of an organic film on the semiconductor element,
It also has the effect of serving as a protection against damage to semiconductor devices.

In addition, when soldering a protruding electrode of a semiconductor element, the organic film acts as a wall and has the effect of preventing the solder paste from flowing to the -1~ side.

In addition, if the organic film is also removed from the lead part that is connected to the board on which the semiconductor device is mounted, no part containing the adhesive of the TAB tape will remain after the semiconductor device is mounted on the board, which will prevent current leakage. It also has the effect of eliminating problems.

[Brief explanation of drawings]

Fig. 1 is a sectional view of the first embodiment of the present invention, Fig. 2(a)
~(1() is a cross-sectional view showing the manufacturing method of the first embodiment of the present invention in the order of steps, FIG. 3 is a cross-sectional view of the second embodiment of the present invention, and FIG. 4 is a cross-sectional view of the second embodiment of the present invention. It is a sectional view of an example mounted on a board. 1... Polyimide tape, 2... Adhesive, 3...
Rolled copper foil, 4.14. Lead, 5... polyimide,
6... Semiconductor element, 7... Aluminum electrode, 8... Passivation, 9... Gold protruding electrode, 10... Device hole, 11... Photosensitive polyimide, 12... Photosensitive polyimide, 13...Resist, 15... Mounting board, 16. Conductor pattern, 17. OL 8 part, ]9.
・Solder protruding electrode.

Claims (1)

[Claims] 1. TAB (Tape Automated Bondin)
In the structure of a semiconductor device using g), a TAB tape consisting of a three-layer structure of a base tape made of an organic substance, an adhesive, and a copper foil is used to penetrate the base tape and the adhesive in order to connect semiconductor elements. A lead made of copper foil, which is provided to connect to the semiconductor element and extends into a device hole opened by the semiconductor element, is connected to the semiconductor element on the side to be connected to the semiconductor element. The TAB tape has an organic film thinner than a protrusion thickness of a protrusion electrode of a conductor provided on a connection electrode portion of the semiconductor element, which is formed on the entire surface of the device hole except for the lead portion;
A structure of a semiconductor device, characterized in that the lead portion from which the organic film has been removed and the semiconductor element are connected via the protruding electrode. 2. In the structure of the semiconductor device according to claim 1, the removed portion of the organic film in the device hole is connected not only to the lead portion connected to the semiconductor element but also to a mounting board on which the semiconductor device is mounted. A structure of a semiconductor device, characterized in that the lead portions that are connected are also removed.