JPH09107006A - Manufacture of film carrier for semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a bonding bump to be easily formed by a method wherein a metallized layer is formed on the surface of a mesa-shaped resin core provided to a conductor lead pattern of a second intermediate form film carrier and its inner lead tip, and a metal film forming process where a film carrier of prescribed form is formed is carried out. SOLUTION: All the surface of a second intermediate form film carrier is flashed with Au to be coated with a metallized layer 27. A photoresist layer 28 is formed on each side of the metallized layer 27, then the metallized layer 27 on a conductor lead pattern 24 and a mesa-shaped polyimide core 16 is exposed, and an Au plating layer 29 is formed on the exposed part of the metallized layer 27. After the photoresist layer 28 is removed, then the exposed metallized layer 27 is removed, and a mesa-shaped polyimide core bump 26 is formed. By this setup, an inner lead bonding bump can easily be formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a film carrier for a semiconductor device, and more particularly, to a resin core bump on the tip of an inner lead that is inner lead bonded to a semiconductor circuit element from a two-layer film tape. The present invention relates to a method for manufacturing a film carrier for a semiconductor device, which has been formed.

[0002]

2. Description of the Related Art Recently, as a method of joining a plurality of electrode pads of a semiconductor circuit element to a conductor lead pattern, a wire bonding method using a wire or a semiconductor circuit element is directly connected to the conductor lead pattern without using a wire. It is roughly classified into an inner lead bonding (wireless bonding) method.

Among these methods, the inner lead bonding is different from the one in which one wire is connected to a plurality of electrode pads of a semiconductor circuit element like wire bonding, unlike the method of forming a conductor lead pattern through bumps on the electrode pads. Since multiple conductor leads can be bonded at once (gang bonding), the bonding time can be significantly shortened, and TAB technology such as LCD driver assembly will be applied in the future (eg, TBGA, CSP, etc.). ) Is attracting attention as a next-generation assembly technology that can be expected.

The film carrier with bumps used for the inner lead bonding assembly of this semiconductor device generally comprises a process of manufacturing a film carrier having conductor leads and a process of forming bumps. The method of forming the bumps formed on each of the plurality of conductor leads of the film carrier is a transfer bump method in which bumps are collectively formed on each of the conductor leads by a transfer method, the conductor lead tips are etched, and the leads are formed on the conductor leads tips. There are a mesa bump method for integrally forming bumps, an Au plating method, and an Au ball bump method for forming one bump at each tip of a conductor lead by using an Au ball bonding method by wire bonding.

In the process of manufacturing a film carrier for a semiconductor device with bumps using the transfer bump method, bumps are formed on a bump forming substrate having a plating mask for forming and reproducing transfer bumps. A step of forming a conductor lead pattern on a resin film laminated with copper foil, and a step of forming a film carrier having an intermediate shape, which comprises a step of forming a plating layer on the surface of the conductor lead; The bumps formed on the substrate are aligned with the conductor leads, heated and pressed, and transferred to the conductor leads.

[0006]

However, there is a problem in that a complicated step is required to form the bump, the formation takes time, the manufacturing cost of the film carrier for a semiconductor device is high, and the cost performance is low. Further, even with the transfer bump, there is a problem that a mass production technology has not been established because a new substrate such as a bump forming substrate, a plating facility for forming a bump on the bump forming substrate and an exposure facility is required.

An object of the present invention is to solve the problems of the prior art and to provide a film carrier for a semiconductor device, which is easy to form the inner lead bonding bump and has high reliability, at low cost.

[0008]

A method for manufacturing a film carrier for a semiconductor device according to claim 1, which is in accordance with the solution to the above-mentioned problems, is a two-layer film tape having a copper foil layer on one surface of a flexible resin film tape. From the above, the film carrier of the first intermediate shape is provided with an outer lead hole in the resin film tape and a device hole in which a plurality of mesa-shaped resin cores are arranged at a position corresponding to an electrode pad of a semiconductor element by a film etching process. And a first shape processing step of forming an inner lead on a plurality of electrode pads of the semiconductor circuit element by etching processing to remove unnecessary portions of the copper foil layer of the first intermediate shape film carrier. The mesa shape is formed on the tip of the conductor lead pattern and the inner lead that are bonded to form an electrical conduction circuit. A second forming step for forming a second intermediate-shaped film carrier provided with a resin core, a conductor lead pattern of the second intermediate-shaped film carrier, and the mesa formed on the tip of the inner lead. It consists of a metal film forming step of forming a metallizing layer on the surface of a resin-shaped resin core to form a film carrier of a desired shape. A film carrier for a semiconductor device having bumps is formed.

[0009]

Since the present invention is configured as described above, it becomes possible to form a bump (for example, 25 μm □) having a fine mesa-shaped resin core as a core from a resin film tape and a bonding pad. Pitch (eg,
The bump height and its uniformity can be easily realized by shrinking (60 μm) and selecting the thickness of the resin film tape. As a result, fine bonding is possible compared to conventional wire bonding. Further, the resin core acts as a buffer function when performing inner lead bonding, and it is possible to prevent damage to the semiconductor circuit element.

Further, as compared with the prior art, a mesa-shaped resin core is formed from a resin film tape, and the resin core is metallized to form a mesa-shaped resin core bump. Then, the film carrier can be formed by the etching process, and the production efficiency can be remarkably improved as compared with the conventional technique. Further, the thick plating process for forming bumps and new equipment are not required, the amount of precious metal used can be reduced, and the manufacturing cost of the film carrier for semiconductors can be reduced.

[0011]

Embodiments of the present invention will now be described with reference to the accompanying drawings to provide an understanding of the present invention. 1 is a cross-sectional view illustrating a film carrier for a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a plan view showing a film pattern of a film carrier having a first intermediate shape according to an embodiment of the present invention. FIG. 3 is a plan view showing a conductor circuit pattern of a film carrier having a second intermediate shape according to an embodiment of the present invention, and FIG. 4 is a process for forming a polyimide core bump according to an embodiment of the present invention. FIG.

First, a copper foil layer 12 is heat-pressed to one surface of a polyimide film (trade name: Kapton, thickness 30 to 50 μm), which is an example of the flexible resin film tape 11 (first).
(See the figure), and then the two-layer film tape 1 wound in a coil
As shown in FIG. 2, a plurality of outer leads 3 are formed by a film etching process while leaving the connecting portions 14 left.
A plurality of mesa-shaped cores 16 made of polyimide are left at the positions corresponding to the holes 15 (which are arranged at four places in this embodiment) and the plurality of electrode pads of the semiconductor circuit element and which are the tips of the inner leads. A polyimide film pattern 18 having a device hole 17 in the state is formed.

These processes are performed by applying a photoresist to both surfaces of the two-layer film tape 13, UV exposing / developing means for forming a resist pattern on the photoresist using a photomask, and exposing the exposed pattern to a film.・ Film that is removed by using hydrazine, which is an example of etching solution ・ Film equipped with means for etching processing, means for removing residual photoresist, etc. ・ Continuous while passing the two-layer film tape through the etching processing step Then, a predetermined holimide film pattern 18 having device holes and outer lead holes is formed. This allows for finer sizes (eg 2
5 μm □), it is possible to form a highly accurate bump core without variation in height, and it is possible to easily realize shrinking of the pitch (for example, 60 μm) between bonding pads. Further, it is possible to easily deal with the arrangement and position of the electrode pads of the semiconductor circuit element such as the arrangement of staggered bumps (not shown). In this case, the required height of the bump can be achieved by selecting the thickness of the resin film tape that forms the core of the bump. Furthermore, it is preferable to perform heat curing at about 350 ° C. after forming the resin core.

Then, the polyimide film 11 is formed.
At the same time, the copper foil layer 12 is exposed in the device hole 17 and the outer lead hole 15, and the device hole 17
A desired shape of the first intermediate shape film carrier 19 in which a plurality of polyimide mesa cores 16 are arranged at positions corresponding to a plurality of electrode pads of the semiconductor circuit element in the region is formed (above, Shape processing step 1).

Next, as shown in FIG. 3, one end portion of the film-etched film carrier 19 having the first intermediate shape is arranged in the device hole 17 in a protruding state, and the leading end thereof is arranged as shown in FIG. A plurality of inner leads 20 each provided with a polyimide mesa core 16 are connected to the inner leads 20, and the respective outer lead holes 15 are connected to the plurality of outer leads 21 arranged in a bridge state and the outer leads 21. Then
Inspection pad 22 for the conduction circuit of the semiconductor device, and
A conductor lead pattern 24 including a frame 23 connecting these is formed.

These processes are performed by means of applying photoresist to both surfaces of the first intermediate-shaped film carrier 19, and UV exposure / development for forming a resist pattern of a conductor lead on the photoresist using a photomask. Means, an etching means for forming a conductor lead pattern 24 for removing the exposure pattern by using cupric chloride, which is an example of a film etching solution, and an etching step for removing the remaining photoresist. A predetermined conductor lead pattern 24 is continuously formed while passing through the film carrier 19 of the first intermediate shape. In this case, since the resist film layer is formed on the surface of the polyimide film pattern 18, the uniform conductor lead pattern 24 can be formed.

Thus, a second intermediate film carrier 25 having a plurality of outer leads 21 and a plurality of inner leads 20 protruding into the device hole 17 and having a mesa-shaped core of polyimide formed at the tip is required. Is formed (the above is the second shape processing step).

Next, the second intermediate film carrier 25 formed by this etching process is subjected to a metal film forming process, as shown in FIG.
The surface of the polyimide mesa-shaped core 16 provided at the front end of 0 is metalized to form an electrical conduction path with each inner lead 20 of the conductor lead pattern 24, and an AU plating layer which is an example of a metal film layer is formed. Formation is performed to form a mesa-shaped polyimide core bump.

These processes are performed as shown in FIG.
(A), (b), (c), (d), and (e) are passed through the film carrier 25 of the second intermediate shape and sequentially processed to complete the semiconductor device film carrier 10. . First, in step (a) of FIG. 4, flash plating of Au, which is an example of a metal film, is performed on the entire surface of the second intermediate shape film carrier 25 by electroless plating to form the metalizing layer 27. Done. Next, FIG.
In the step (b), a photoresist is applied to both surfaces of the photoresist layer 28 to form a photoresist layer 28, and then UV exposure and development are performed to form the conductor lead pattern 24 and the metalizing layer 27 of the mesa-shaped polyimide core 16. Expose. Next, in step (c) of FIG. 4, an Au plating layer 29, which is an example of a metal plating layer, is formed on the exposed metalizing layer 27 by electrolytic plating. Subsequently, in the step of FIG. 4D, the photoresist layer 28 is removed. Further, in step (e) of FIG. 4, a peeling process for removing the exposed metalizing layer 27 is performed to form a mesa-shaped polyimide core bump 26. In this case, the metallizing layer 27 is formed by using the electroless plating method, but it is also possible to form it by using the sputtering method (the above is the metal film layer forming process step).

[0020]

As described above, when the method for manufacturing a film carrier for a semiconductor device of the present invention is used, a film carrier provided with mesa-shaped polyimide core bumps can be formed consistently by etching. Therefore, compared to the conventional technology, a complicated process is not required for forming the bump, the forming time is shortened, the manufacturing cost of the semiconductor device film carrier is reduced, and the mass production technology can be established. it can.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a film carrier for a semiconductor device according to an embodiment of the present invention.

FIG. 2 is a plan view showing a film pattern of a film carrier having a first intermediate shape according to an embodiment of the present invention.

FIG. 3 is a plan view showing a conductor circuit pattern of a second intermediate shape film carrier according to an embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a process of forming a metal film layer according to the embodiment of the present invention.

[Explanation of symbols]

 10 Film Carrier for Semiconductor Device 11 Flexible Resin (Polyimide) Film Tape 12 Copper Foil Layer 13 Two-Layer Film Tape 14 Connection Part 15 Outer Lead Hole 16 Mesa-shaped Polyimide Core 17 Device Hole 18 Polyimide Film Pattern 19 First Intermediate film carrier 20 Inner lead 21 Outer lead 22 Inspection pad 23 Frame 24 Conductor lead pattern 25 Second intermediate shape film carrier 26 Mesa-shaped polyimide core bump 27 Metallizing layer 28 Photoresist film 29 Au plating layer 30 sprocket holes

Claims (1)

[Claims] 1. A method of manufacturing a film carrier for a semiconductor device having a resin core bump on the tip of an inner lead, wherein a flexible resin film tape has a copper foil layer on one side thereof Forming a first intermediate-shaped film carrier by etching, forming outer lead holes in the resin film tape and device holes in which a plurality of mesa-shaped resin cores are arranged at positions corresponding to electrode pads of a semiconductor element. The first shape processing step and the etching processing are performed to remove unnecessary portions of the copper foil layer of the film carrier having the first intermediate shape, and inner lead bonding is performed to a plurality of electrode pads of the semiconductor circuit element, and electrical processing is performed. Of the mesa shape at the tip of the conductor lead pattern and the inner lead for forming a static conduction circuit. A second forming step for forming a second intermediate shape film carrier provided with the resin core of
A process for forming a metalizing layer on the surfaces of the conductor lead pattern of the second intermediate shape film carrier and the mesa-shaped resin core formed on the tip of the inner lead is performed to form a film carrier of a desired shape. A method of manufacturing a film carrier for a semiconductor device, comprising a metal film forming process.