JP3226010B2 - Method of manufacturing film carrier for semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a film carrier for a semiconductor device, and more particularly to a method for manufacturing a film carrier for a semiconductor device, in which a resin core bump is provided at the tip of an inner lead which is 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 on which is formed.

[0002]

2. Description of the Related Art In recent years, a plurality of electrode pads of a semiconductor circuit element and a conductor lead pattern are bonded to each other by a wire bonding method using a wire or a semiconductor circuit element directly connected to a conductor lead pattern without using a wire. It is roughly divided into the inner lead bonding (wireless bonding) method.

Among these methods, the inner lead bonding is different from the method of connecting one wire at a time to a plurality of electrode pads of a semiconductor circuit element as in the case of wire bonding. Since a plurality of conductor leads can be bonded together (gang bonding), the bonding time can be significantly reduced, and its application development (for example, TBGA, CSP, etc.) including an assembly for an LCD driver as a TAB technology can be achieved. ) Is attracting attention as a next-generation assembly technology that can be expected.

A film carrier with a bump 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 a bump. The method of forming the bumps formed on each of the plurality of conductor leads of the film carrier includes a transfer bump method in which bumps are collectively formed on each of the conductor leads by a transfer method; There is an Au ball bump method in which one bump is formed at each end of a conductor lead using a mesa bump method, an Au plating method, or an Au ball bonding method by wire bonding, in which a bump is integrally formed.

In the process of manufacturing a film carrier for a semiconductor device having bumps using the transfer bump method, the bumps are formed on a bump forming substrate having a plating mask for forming and reproducing transfer bumps. Forming a film carrier having an intermediate shape comprising: a step of forming a conductor lead pattern on a resin film on which a copper foil is laminated; and a step of forming a plating layer on the surface of the conductor lead. A bonding step of aligning the bumps formed on the substrate with the conductor leads, heating and pressing, and transferring the bumps to the conductor leads.

[0006]

However, there is a problem in that a complicated process is required for the formation of the bump, the formation takes a long time, the production cost of the film carrier for a semiconductor device is high, and the cost performance is low. In addition, transfer bumps require new equipment such as a bump forming substrate, plating equipment for forming bumps thereon, and exposure equipment, and there is a problem that mass production technology has not been established.

An object of the present invention is to solve the problems of the prior art and to provide a highly reliable film carrier for a semiconductor device at a low cost in which a bump for inner lead bonding can be easily formed.

[0008]

According to a first aspect of the present invention, there is provided a method of manufacturing a film carrier for a semiconductor device, comprising: a flexible resin film tape having a copper foil layer on one surface. A first intermediate film carrier having an outer lead hole in the resin film tape and a device hole in which a plurality of mesa resin cores are arranged at positions corresponding to the electrode pads of the semiconductor element by film etching. A first shape processing step of forming the first intermediate shape film carrier, and an etching process to remove unnecessary portions of the copper foil layer of the first intermediate shape film carrier. The mesa-shaped conductor lead pattern for bonding and forming an electrically conductive circuit is formed at the tip of the inner lead. A second forming step of forming a second intermediate-shaped film carrier provided with a resin core; and a conductor lead pattern of the second intermediate-shaped film carrier and the mesa formed at the tip of the inner lead. A metal film forming process for forming a metal carrier layer on the surface of the resin core in the form of a metal film to form a film carrier of a required shape. A semiconductor device film carrier provided with bumps is formed.

[0009]

Since the present invention is configured as described above, it is possible to form a bump (for example, 25 μm square) having a fine mesa resin core as a core from a resin film tape and to form a bonding pad. Pitch (for example,
The height of the bumps and the uniformity thereof can be easily achieved by selecting a shrink of 60 μm) and the thickness of the resin film tape. As a result, fine bonding is possible as compared with conventional wire bonding. Further, the resin core acts as a buffering function when performing inner lead bonding, thereby preventing the semiconductor circuit element from being damaged.

Furthermore, 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, a film carrier can be formed by etching, and the production efficiency can be remarkably improved as compared with the conventional technology. Further, a thick plating step for bump formation and new equipment are not required, the amount of noble metal used can be reduced, and the manufacturing cost of the film carrier for semiconductor can be reduced.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention. Here, FIG. 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 first intermediate-shaped film carrier according to the 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 the embodiment of the present invention. FIG. 4 is a diagram illustrating a process of forming a polyimide core bump according to the embodiment of the present invention. FIG.

First, a copper foil layer 12 is heat-welded to one side of a polyimide film (trade name: Kapton, thickness 30 to 50 μm) which is an example of a flexible resin film tape 11 (first type).
See figure) and coiled two-layer film tape 1
3 is subjected to a film etching process, as shown in FIG.
Holes 15 (located at four locations in the present embodiment) correspond to a plurality of electrode pads of the semiconductor circuit element, and a plurality of polyimide mesa-shaped cores 16 are left at positions to be the leading ends of the inner leads. A polyimide film pattern 18 having a device hole 17 in a state is formed.

These processes include means for applying a photoresist on both sides of the two-layer film tape 13, means for UV exposure and development for forming a resist pattern on the photoresist using a photomask, and means for applying the exposed pattern to a film.・ Film with hydrazine which is an example of an etchant ・ Film provided with means for etching processing, means for removing residual photoresist, etc. Continuously while passing the two-layer film / tape through the film etching processing step The formation processing of a predetermined polyimide film pattern 18 provided with device holes and outer lead holes is performed. Thereby, a fine size (for example, 2
5 μm □), it is possible to form a bump core with high precision without variation in height, and it is possible to easily realize shrinking of the pitch between bonding pads (for example, 60 μm). Further, it is possible to easily cope 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 necessary height of the bump can be achieved by selecting the thickness of the resin film tape forming the core of the bump. Further, it is preferable to perform heat curing at about 350 ° C. after forming the resin core.

Thus, the polyimide film 11
In addition, the copper foil layer 12 is exposed in the device hole 17 and the outer lead hole 15, and
A required shape of a first intermediate film carrier 19 in which a plurality of polyimide mesa-shaped cores 16 are arranged at positions corresponding to a plurality of electrode pads of the semiconductor circuit element in the region is formed (the above is referred to as a "first"). 1 shape processing step).

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

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

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

Next, as shown in FIG. 1, the second intermediate film carrier 25 formed by this etching process is subjected to a metal film forming process as shown in FIG.
The metallization of the surface of the polyimide mesa core 16 provided at the front end of the metal lead layer forms an electrical conduction path with each of the inner leads 20 of the conductor lead pattern 24, and an AU plating layer, which is an example of a metal film layer, is formed. Then, a mesa-shaped polyimide core bump is formed.

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

[0020]

As described above, when the method of manufacturing a film carrier for a semiconductor device according to the present invention is used, a film carrier provided with a mesa-shaped polyimide core / bump is consistently formed by etching. Therefore, compared to the prior art, a complicated process is not required for forming the bump, the formation time is shortened, the manufacturing cost of the film carrier for the semiconductor device 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 first intermediate-shaped film carrier according to the embodiment of the present invention.

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

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

[Explanation of symbols]

 Reference Signs List 10 Film carrier for semiconductor device 11 Flexible resin (polyimide) film tape 12 Copper foil layer 13 Two-layer film tape 14 Connecting portion 15 Outer lead hole 16 Mesa-shaped polyimide core 17 Device hole 18 Polyimide film pattern 19 First Intermediate shape 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-like polyimide core / bump 27 Metallizing layer 28 Photoresist film 29 Au plating layer 30 sprocket holes

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/60

Claims (1)

(57) [Claims] 1. A method of manufacturing a film carrier for a semiconductor device having a resin core / bump at the tip of an inner lead, comprising: a step of forming a film resin from a two-layer film tape having a copper foil layer on one side of a flexible resin film tape; Forming a first intermediate-shaped film carrier having 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 positions corresponding to the electrode pads of the semiconductor element by etching; (1) by performing a shape processing step and etching processing to remove unnecessary portions of the copper foil layer of the first intermediate-shaped film carrier, and performing inner lead bonding to a plurality of electrode pads of the semiconductor circuit element; Lead pattern for forming a conductive circuit and the mesa-shaped A second forming processing step of forming a second intermediate-shaped film carrier provided with a resin core of
A metallizing layer is formed on the surface of the mesa-shaped resin core formed on the conductor lead pattern of the second intermediate shape film carrier and the tip of the inner lead to form a film carrier of a required shape. A method for manufacturing a film carrier for a semiconductor device, comprising: a metal film forming step.