JP2973953B2 - TCP tape structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a TCP tape structure in which an IC chip is mounted on a base film.

[0002]

2. Description of the Related Art In recent years, a TCP tape structure in which an IC chip is mounted on a base film has been widely used in order to enable high-density mounting of the IC chip and to improve a degree of freedom of mounting. As the number of output pins increases, the external shape of the IC chip has become rectangular.

FIG. 5 shows a TCP tape structure, and FIG. 6 is a sectional view showing a TCP chip structure after resin sealing. An IC chip is arranged in a device hole 2 opened in the base film 1, and a tip of an inner lead 4 protruding into the device hole 2 is joined to an electrode of the IC chip 3, and the IC chip 3 is connected to the inner lead 4. It is suspended and arranged in the device hole 2 of the base film 1.

[0004] A plurality of inner leads 4 are provided in parallel with each other on the long side 3a and the short side 3b of the IC chip 3, and the inner leads 4 are connected to the long side 3a and the short side of the IC chip 3 respectively. The entire IC chip 3 is suspended from the side 3b. The inner lead 4 is connected to an external circuit or the like via an internal wiring 7 on the base film 1.

[0005] Further, the I
As shown in FIG. 6, the C chip 3 was covered with a thermosetting resin 8 and hermetically sealed.

[0006]

The base film 1 is made of a material that expands thermally when the hermetic sealing resin 8 is thermally cured.

Since the device hole 2 opened in the base film 1 is shaped like a rectangle following the outer shape of the IC chip 3, the base film 1 in the region of the device hole 2 of the base film 1 when thermally expanded is formed. The thermal expansion of the device hole 2 particularly on the long side (the left-right direction in FIG. 6) is larger than that on the short side.

Therefore, a tensile force (stress) due to the thermal expansion of the base film 1 is applied to the inner lead 4 joined to the short side 3b of the IC chip 3, and the inner lead 4 is broken by the stress, or the inner lead 4 is broken. 4 and I
There is a possibility that a trouble may occur in a joint portion of the C chip 3 with the electrode.

It is an object of the present invention to provide a TCP tape structure having a structure for absorbing and relaxing a stress applied to an inner lead due to a thermal expansion of a base film.

[0010]

In order to achieve the above object, a TCP tape structure base film according to the present invention,
A TCP tape structure having an IC chip and a stress buffer, wherein the IC chip is hermetically sealed with a thermosetting resin. The base film is thermally expanded when the hermetically sealing resin is thermoset. Having a device hole and an inner lead.
An opening for receiving the chip, the inner lead is a conductor whose tip projects into a device hole of the base film, and the IC chip has an inner lead joined to the electrode, and the device hole of the base film is passed through the inner lead. It is suspended in the, the stress buffer,
Elastic deformation due to thermal expansion of the base film, and extends from the base film to the device hole.
The extension of the inner lead is formed on the surface.
It supports the base of the inner lead and absorbs and reduces the stress applied to the inner lead due to the thermal expansion of the base film.

[0011] The stress buffer is formed integrally with the opening edge of the device hole, and is shaped in a serpentine pattern shape, said device Ho from the base film
It is provided so as to extend to the file .

A plurality of the stress buffering parts are arranged in parallel.
Extending from the base film to the device hole
It is provided as .

[0013] The inner leads are wiring-processed on the stress buffer in a meandering pattern shape.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a plan view showing a TCP tape structure according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line AA 'of FIG.

In the drawing, T according to the first embodiment of the present invention is shown.
The CP tape structure consists of a base film 1, an IC chip 3
And a stress buffer 9, and hermetically seals the IC chip 3 with a thermosetting resin 8.

The base film 1 is made of a material having a property of thermally expanding when the hermetic sealing resin 8 is thermally cured, and has a device hole 2 and an inner lead 4.
The device hole 2 is an opening for receiving the IC chip 3.
Of the device hole 2.

The IC chip 3 has an inner lead 4 bonded to an electrode 5 and is suspended in the device hole 2 of the base film 1 via the inner lead 4. Also IC
The chip 3 is hermetically sealed with a thermosetting resin 8 while being suspended from the inner lead 4. Reference numeral 6 denotes a resin area sealed with the resin 8, and a part of the base film 1 and the inner leads 4 that are inwardly provided at the opening edge of the device hole 2 are embedded in the resin 8. Becomes

Further, the stress buffering section 9 includes the base film 1.
Elastically deforms with the thermal expansion of the base film 1, supports the base of the inner lead 4, and absorbs and relaxes the stress applied to the inner lead 4 due to the thermal expansion of the base film 1. The stress buffer 9 shown in FIG.
And is formed integrally with the opening edge of the device hole 2 to form a meandering pattern.

The inner leads 4 are subjected to wiring processing on the stress buffer 9 in a meandering pattern, and are connected to the internal wiring 7 on the base film 1. The inner leads 4 are plated with Sn.

In the first embodiment, when the hermetic sealing resin 8 is thermally cured as shown in FIG. 2, the base film 1 thermally expands from the original dimension W to an extended dimension Wh, and the stress is reduced. It is applied to the inner lead 4 connected to the short side 3b of the IC chip 3.

According to the present invention, the stress buffer 9 having the meandering pattern shape is elastically deformed by the stress accompanying the thermal expansion of the base film 1, and absorbs and relaxes the stress caused by the base film.

As a result, the stress caused by the base film 1 applied to the inner leads 4 decreases, and the inner leads 4
Will not be broken. In addition, inner lead 4
An unreasonable force is not applied to the joint between the IC chip 3 and the electrode 5.

(Embodiment 2) FIG. 4 is a plan view showing Embodiment 2 of the present invention.

In the second embodiment of the present invention shown in FIG. 4, a plurality of stress buffer portions 9 are provided in parallel.

According to the second embodiment, the inner leads 4
Can be divided into a plurality of stress buffer portions 9 for wiring processing, and the area of the wiring processing portion of the inner lead 4 in each stress buffer portion 9 can be reduced, whereby the elastic deformation degree of the stress buffer portion 9 can be reduced. Is easily set to a desired value, and there is an advantage that the stress applied to the inner lead 4 can be appropriately absorbed and alleviated.

[0027]

As described above, according to the present invention, the stress caused by the base film applied to the inner lead can be absorbed and alleviated, the break of the inner lead can be prevented, and the connection between the inner lead and the electrode of the IC chip can be prevented. It is possible to prevent excessive force from being applied to the joint.

Further, since the inner leads are subjected to wiring processing in accordance with the meandering pattern of the stress buffer portion, even if the stress buffer portion is elastically deformed, an excessive force such as a stress caused by a base film may be applied to the inner lead. Absent.

Further, by installing the stress buffer portions in parallel, the inner leads can be set separately.
The wiring area of the stress buffering portion can be reduced, so that the elastic deformation by the stress buffering portion can be appropriately selected.

[Brief description of the drawings]

FIG. 1 is a plan view showing a structure of a TCP tape according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line A-A 'of FIG.

FIG. 3 is an enlarged view showing a stress buffer unit of FIG.

FIG. 4 is a diagram showing a second embodiment of the present invention.

FIG. 5 is a plan view showing a conventional example.

FIG. 6 is a sectional view taken along line B-B ′ of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base film 2 Device hole 3 IC chip 4 Inner lead 8 Resin 9 Stress buffer

Claims (4)

(57) [Claims] 1. A TCP tape structure having a base film, an IC chip, and a stress buffer, wherein the IC chip is hermetically sealed with a thermosetting resin, wherein the base film is used for hermetic sealing. It is made of a material that has the property of expanding thermally when the resin is thermally cured.
The device hole has an inner lead, and the device hole is an opening for receiving the IC chip. The inner lead is a conductor having a tip protruding into the device hole of the base film. The IC chip has an inner lead joined to an electrode. A stress buffer, which is suspended in the device hole of the base film via the inner lead, and is elastically deformed in accordance with the thermal expansion of the base film.
Extend to the chair hole, and the extension of the inner lead is displayed.
A TCP tape structure formed on a surface to support a base of an inner lead and absorb and reduce stress applied to the inner lead due to thermal expansion of a base film. Wherein said stress buffer is formed integrally with the opening edge of the device hole, and is shaped in a serpentine pattern shape, said device hole from the base film
The TCP tape structure according to claim 1, wherein the TCP tape structure is provided so as to extend . 3. A plurality of stress buffering parts are arranged in parallel.
Extending from the base film to the device hole.
TCP tape structure according to claim 2, characterized in that provided Te. 4. The TCP according to claim 1, wherein the inner leads are wiring-processed on the stress buffer according to a meandering pattern shape.
Tape structure.