JPH10335377A - Tape-carrier package, flexible tape substrate and producing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiring lead break prevention effect. SOLUTION: A bent slit hole 7 is formed by a dry etching method using a laser beam or an ion plasma. A wiring lead 5 is stuck on a film 1 by an adhesive agent 8. Within the range of the bent slit hole 7, the film 1 is formed in an identical shape with respect to the plane with the wiring lead 5 and supports the wiring lead 5 while being arranged, namely, lined at a position corresponding to the wiring lead 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible tape substrate and a tape carrier package using the same, and more particularly to a structure of a tape carrier package and a flexible tape substrate having a bent portion, and a method of manufacturing a flexible tape substrate having a bent portion. Things.

[0002]

2. Description of the Related Art A conventional tape carrier package (hereinafter referred to as TCP) having a bent portion and a flexible tape substrate (hereinafter referred to as an FPC) have one long hole formed in a bent portion of a film. A wiring lead is provided so as to cross the hole. This is because the wiring leads are easily bent by forming long holes in the film. Hereinafter, this elongated hole is referred to as a bent slit hole.

However, only by forming a bending slit hole, the wiring lead at the bent portion is in a suspended state, and when bent, the wiring lead has a radius of 0.1 mm.
Since it bends at a small curvature, it breaks in several bends.

[0004] In recent years, the following measures have been known in order to prevent breakage due to bending several times. 4 to 6 described below correspond to the TCP shown in FIG. 1 of the present invention.
FIG. 4 is a cross-sectional view of a position corresponding to the AA cross section of FIG.

As a first conventional countermeasure, as shown in a sectional view of FIG. 4, a film is formed in a bending slit hole of a film 1 formed for bending and around a bending slit hole.
Low elastic resin 10 having a smaller elastic modulus than PC film 1
Is applied and cured so that the low-elastic resin 10 supports the suspended wiring leads 5 crossing the bending slit.
It is a PC. As a result, as compared with the case where the wiring lead 5 is suspended in the air, the curvature of the wiring lead 5 when bent is increased, and the number of times of bending until the wiring lead 5 is broken is increased.

As shown in the cross-sectional view of FIG. 5, the second conventional countermeasure is that the FPC having the structure of the first countermeasure is also provided with F
The FPC has a structure in which a wiring lead 5 is sandwiched between resins having a low elastic modulus by applying and curing a second low elastic resin 11 having a lower elastic modulus than the film 1 of the PC. As a result, the curvature when the wiring lead 5 is bent is further increased and the number of times of bending before breaking is further increased as compared with the structure of the first conventional countermeasure.

Here, the manufacturing process of the FPC of the second conventional measure will be briefly described with reference to FIG.

First, in the step (1), a device hole, which is a first hole for disposing an integrated circuit element, and a bending, which is a second hole for forming a bent portion, in a film 1 made of polyimide or the like to which an adhesive 8 has been applied. The slit hole 7 is punched out by a mold, and a copper foil 12 is attached.

Next, in the step (2), the film 1 is inserted into and around the bending slit hole 7 as the second hole.
The first low-elasticity resin 10 having a smaller elastic modulus is applied by a printing method and cured.

Next, in step (3), a photoresist is applied to the copper foil 12 and dried, and a protective resist is applied to the film side so as to cover device holes and bending slit holes 7 not shown in the drawing. dry.

Next, the photoresist is selectively exposed,
After the development, the copper foil is selectively etched with an etchant to form inner leads, wiring leads 5, and outer leads.

Finally, in the step (4), a resin having a lower elastic modulus than the film 1 is applied to the area of the bent slit hole 7 and its periphery from the wiring lead side by a printing method and cured. Then, a solder resist for protecting the wiring leads 7 other than the bent portions is applied by a printing method as required, and after drying, a metal plating such as tin plating is applied to a portion where the copper foil is exposed to complete the FPC.

Further, the first countermeasure FPC can be obtained by omitting the step (2).

[0014]

However, in the first conventional measure, in order to prevent the breakage of the wiring lead at the bent portion, a step of applying a low elasticity resin compared to the FPC having no bent portion is required. Two additional steps of curing are required, and the conventional FPC of the second countermeasure requires four additional steps, which is twice that of the conventional FPC. was there.

Further, since a continuous bending slit hole is required at the bent portion of the film, there is a problem that the copper foil is bent in the bending slit hole at the time of attaching the copper foil and the strength of the copper foil is reduced.

[0016]

According to the present invention, to solve such a problem, an inner lead extends in a cantilever manner at a position corresponding to an electrode of an integrated circuit element in a first hole of a flexible tape substrate. In the structure of a tape carrier package obtained by joining the inner lead to the electrode of the integrated circuit element and then sealing the integrated circuit device including the joined portion with a resin, the wiring in which the inner lead extends on the flexible tape substrate A lead, an outer lead for connecting to an external substrate located at an end of the wiring lead opposite to the inner lead, and a second hole group of a flexible tape substrate opened in the wiring lead area. A tape carrier package, wherein a part of a flexible tape substrate is lined with a wiring lead provided in the area of the second hole group. To provide over-di.

[0017] Further, an inner lead extends in a cantilever manner at a position corresponding to an electrode of the integrated circuit element in a first hole of the film, and a wiring lead having the inner lead extending on the film; An outer lead for connecting to an external substrate located at the end opposite to the inner lead, and a second hole group of an open film in the wiring lead area, wherein the second hole group Provided is a flexible tape substrate, wherein a part of a film is lined with a wiring lead provided in a region.

Further, an inner lead extends in a cantilever manner at a position corresponding to the electrode of the integrated circuit element in the first hole of the film, and a wiring lead having the inner lead extending on the film; After forming an outer lead for connection with an external board located at the end opposite to the inner lead, the film lead is formed in the wiring lead area.
A method for manufacturing a flexible tape, characterized in that laser irradiation is selectively performed from the wiring lead side using a wiring lead as a mask to form a hole group, and a film excluding a portion immediately below the wiring lead is etched.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view of a tape carrier package (TCP) showing one embodiment of the present invention. This TCP
A liquid sealing material (not shown) is located in the area of the device hole 3 including the integrated circuit element 2 by aligning and joining the inner lead 4 of the flexible tape substrate (FPC) of the present invention and the electrode of the integrated circuit element 2. The resin is applied and cured to complete.

The inner lead 4 extends from the device hole 3 on the film 1, and connects the outer lead 6 and the inner lead 4 as the wiring lead 5 on the film 1. Usually, the inner leads 4, the wiring leads 5 and the outer leads 6 are formed of a copper foil having a thickness of 18 to 35 microns. Film 1 is 25
Typically, micron to 125 micron polyimide films are used.

When the TCP of the present invention is mounted on an external substrate, the TCP at the position of the bending slit hole 7 is 90 degrees or 18 degrees.
It is bent and mounted at an angle of 0 degrees.

In the plan view of FIG. 1, the bent slit hole 7 looks like one long hole, but actually has a structure in which the holes are gathered as shown in FIG.

In the FPC of the present invention, the wiring leads 5 are adhered to the film 1 with an adhesive 8 as shown in FIG.
The film 1 has the same shape in plan view as the wiring lead 5 within the range of the bending slit hole 7 in FIG. 1, and is disposed at a position corresponding to the wiring lead 5, that is, supports the wiring lead 5 in a backed form. doing.

With this structure, as compared with the case where the wiring lead 5 is suspended in the air, the wiring lead 5 has a larger curvature when bent, and the number of times of bending before breaking is increased.
In this case, the same effect as that of the first embodiment can be obtained. Moreover, unlike the first and second countermeasures of the conventional example, there is no need for a step of applying and curing the resin using a low elasticity resin.

FIG. 2 shows a case of a three-layer FPC using an adhesive, but a two-layer FPC having a structure in which wiring leads are directly attached to a film without using an adhesive may be used.

Hereinafter, a method of manufacturing the FPC of the present invention will be described.

First, a device hole, which is a first hole for disposing an integrated circuit element, and other holes (not shown) are punched out by a mold as necessary on a film 1 made of polyimide or the like to which an adhesive 8 has been applied. Paste. Here, the punching of the bending slit hole 7 of the second hole forming the bending portion shown in FIG. 6A is not performed.

In the next step, a photoresist is applied on the copper foil and dried, and a protective resist is applied and dried on the film side so as to cover the device holes.

Next, the photoresist is selectively exposed,
After the development, the copper foil is selectively etched with an etchant to form inner leads, wiring leads 5, and outer leads.

In the last step, a mask 12 having a hole opened in the same shape as the bent slit hole 7 of FIG. 1 is prepared.
As shown in FIG. 3, the opening hole of the mask 12 is arranged on the wiring lead side of the FPC so as to overlap the portion where the bending slit of the FPC in which the wiring lead 7 is formed is formed. Thereafter, the FPC is irradiated with a laser beam through the mask to form a mask 12.
Then, the adhesive and the film in the portion where the laser light is not blocked by the wiring leads 5 are dry-etched. Here, an excimer laser, a carbon dioxide laser, or the like can be used as the laser light. Further, a dry etching method such as ion plasma may be used instead of laser light. In this manner, the FPC in which the film and the adhesive in the portion where the laser beam is not blocked by the mask 12 and the wiring lead 5 are etched is shown in FIG.
The wiring leads 5 are selectively lined with a film as in the cross-sectional shape shown in FIG.

Then, a solder resist for protecting the wiring leads 7 other than the bent portion is applied by a printing method as required, and after drying, a metal plating such as tin plating is applied to a portion where the copper foil is exposed to complete the FPC. .

[0033]

As described above, in the tape carrier package and the flexible tape substrate according to the present invention, it is not necessary to provide a continuous bending slit hole in the bending portion of the film. There is no possibility that the strength of the copper foil is reduced by bending in the holes.

Further, since it is not necessary to apply a low elasticity resin to the bent portion of the film, the manufacturing process is shortened as compared with the prior art, and the cost of the TCP or F is shortened with a short delivery time.
PC can be supplied.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a tape carrier package of the present invention and a flexible tape substrate used therein.

FIG. 2 is a cross-sectional view of a bent portion showing an embodiment of the tape carrier package of the present invention or a flexible tape substrate used therein.

FIG. 3 is a cross-sectional view of a bent portion showing an embodiment of the tape carrier package of the present invention or a flexible tape substrate used therein.

FIG. 4 is a plan view of a bent portion showing one embodiment of a conventional tape carrier package or a flexible tape substrate used for the same.

FIG. 5 is a cross-sectional view of a bent portion showing another embodiment of a conventional tape carrier package or a flexible tape substrate used therein.

FIG. 6 is a cross-sectional view of a bent portion showing a manufacturing process in an embodiment of a conventional tape carrier package or a flexible tape substrate used for the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Film 2 ... Integrated circuit element 3 ... Device hole 4 ... Inner lead 5 ... Wiring lead 6 ... Outer lead 7 ... Bending slit hole 8 ... Adhesive 9 ... Laser beam 10 ... First low elasticity resin 11 ... Second low elasticity resin 12 ... Mask

Claims (3)

[Claims] An inner lead extends in a cantilever manner at a position corresponding to an electrode of an integrated circuit device in a first hole of a flexible tape substrate, and after approximately connecting the inner lead to an electrode of the integrated circuit device, a general bonding is performed. In a tape carrier package obtained by resin-sealing an integrated circuit device including a part, the inner lead is located at a wiring lead extending on a flexible tape substrate and at an end of the wiring lead opposite to the inner lead. An outer lead for connecting to an external board, the wiring lead area has a second hole group of the flexible tape substrate opened, and the wiring lead provided in the second hole group area has A tape carrier package characterized in that a part of a flexible tape substrate is lined. 2. An inner lead extending in a cantilever manner at a position corresponding to an electrode of an integrated circuit element in a first hole of a film,
A wiring lead having the inner lead extended on the film, and an outer lead for connecting to an external substrate located at an end of the wiring lead opposite to the inner lead,
The wiring lead area has a second group of holes in the film that is open, and the wiring leads provided in the area of the second group of holes are partially lined with a film. Flexible tape substrate. 3. An inner lead extending in a cantilever manner at a position corresponding to an electrode of an integrated circuit element in a first hole of a film,
After forming the wiring lead in which the inner lead extends on the film and the outer lead for connecting to an external substrate located at the end of the wiring lead opposite to the inner lead, the wiring lead area In order to form the second hole group of the film, dry etching treatment such as laser irradiation or ion plasma irradiation was selectively performed from the wiring lead side using the wiring lead as a mask, and it was confirmed that the film except the area immediately below the wiring lead was etched. Characteristic method for producing flexible tape.