JPH0364938A - Film carrier and semiconductor device - Google Patents

Abstract

PURPOSE:To contrive to use a film carrier, which facilitates a positioning at the time of bonding of a semiconductor element with leads and by which a resin covering is also easily performed, by a method wherein an insulative film with through holes provided therein is used, bump-shaped metallic projected matters are provided at the opening parts of the through holes and moreover, a thermally adhesive resin layer is provided on the bump-shaped metallic projected matter formation surface of the insulative film. CONSTITUTION:A film carrier has leads 3 at opening parts in one surface of an insulative film 2 having a plurality of fine through holes 4 in its thickness direction, a metallic substance 5 is filled only in the lead formation through holes 4 and bump- shaped metallic projected matters 6 are formed at opening parts in the other surface of the film 2. Moreover, a thermally adhesive resin layer 8 is provided on a bump- shaped metallic projected matter formation surface and the projected matters 6 are covered and protected. At this time, it ts desirable to form the thickness of the layer 8 in 0.05mum or thicker from the viewpoint of a covering protection and the improvement of reliability. A semiconductor element 1 has electrodes 7 for external connection use, such as Al electrodes and the like, on the surface on one side of the element 1 and these electrodes 7 and the projected matters 6 of the film carrier are electrically connected to each other by an normal bonding method.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a film carrier and a semiconductor device.

<Prior Art> A film carrier method has been used as one of the mounting methods for semiconductor elements.

Various methods have been proposed for bonding (inner lead bonding) between finger-shaped leads and semiconductor elements in the film carrier method, in which bumps (protruding electrodes) are formed on the electrode surface of the semiconductor element and these bumps are utilized. A method has been proposed in which the film is bonded to a lead on a film carrier.

However, the process of forming bumps on the electrode surface involves sporadic etching of an adhesive layer of metals such as titanium/chromium and a barrier layer of metals such as copper, platinum, and palladium to prevent diffusion of the bump-forming metal. Not only does it require a complicated process of forming bumps using methods such as metallization and vapor deposition, and then forming bumps using gold or other materials using a plating method, but it is also difficult to avoid contamination and damage to the semiconductor elements, making this method by no means a good method. cannot be said.

Additionally, a method has been proposed in which bumps are formed on the leads on the film carrier side for bonding, contrary to the above method, but like the above method, this method also requires a complicated bump forming process. .

Additionally, a bumpless film carrier using an anisotropic conductive film has been proposed (Japanese Patent Laid-Open No. 63-4633
The anisotropic conductive film used is one in which conductive particles such as carbon black, graphite, nickel, copper, silver, etc. are dispersed in an electrically insulating resin film, and the particles are oriented in the thickness direction of the film. However, in order to obtain a film that exhibits homogeneous anisotropic conductivity, the manufacturing method is complicated, and if the orientation of the conductive particles is insufficient, the inner lead bonding between the electrode and the lead of the semiconductor element is uncertain. This may result in lower connection reliability.

On the other hand, as electronic devices have become thinner, smaller, and lighter in recent years, there has been a similar demand for the packaging form of semiconductor devices. Packages include TAB and CO.
There is a tendency for thin semiconductor devices such as B type to increase. Generally, such semiconductor devices are coated with a protective resin such as polyimide resin or silicone resin on the surface of the semiconductor element in a separate process in order to protect them electrically, mechanically, or chemically from the outside. A protective film is formed by applying bottling to the vicinity and heating and drying.

However, with resin coating using this method, the connection parts (electrode parts) of semiconductor elements may not be sufficiently covered or voids may be present, so it is not necessarily sufficient in terms of reliability. It is something.

<Problems to be Solved by the Invention> The present invention provides a film carrier that solves the drawbacks of the above-mentioned conventional techniques. Specifically, the present invention provides a film carrier that facilitates positioning when bonding a semiconductor element and a lead, making it extremely easy to manufacture a semiconductor device, and The object of the present invention is to provide a film carrier that can be easily coated with a resin, and a semiconductor device using this film carrier.

Means for Solving the Problems> As a result of extensive studies, the present inventors used an insulating film with conductive through-holes on its front and back surfaces, and provided bump-shaped metal protrusions at the openings of the through-holes. The present inventors have discovered that a film carrier that can achieve the above object can be obtained by providing a heat-adhesive resin layer on the surface of the insulating film on which bump-shaped metal protrusions are formed, and have completed the present invention.

That is, the present invention has a lead in an opening on one side of an insulating film having a plurality of fine through holes in the thickness direction, and a conductive path made of a metal material is formed only in the lead forming through hole, and the other side of the through hole A film carrier having a bump-shaped metal protrusion formed in the opening, a heat-adhesive resin layer formed on the surface of the insulating film on which the bump-shaped metal protrusion is formed, and a film carrier for external connection to the film carrier. The present invention provides a semiconductor device formed by connecting semiconductor elements having electrodes.

<Example> The present invention will be described below based on an example shown in the drawings.

FIG. 1 is a cross-sectional view showing an example of a semiconductor device using the film carrier of the present invention. Only the lead forming through hole 4 is filled with a metal substance 5, and a bump-shaped metal protrusion 6 is formed at the opening on the other side. Further, a thermal adhesive resin layer 8 is provided on the bottom surface of the bump-shaped metal protrusion to cover and protect the bump-shaped metal protrusion 6. At this time, it is preferable that the thickness of the resin layer 8 is 0.05 μm or more from the viewpoint of protecting the coating and improving reliability.

The semiconductor element 1 has an external connection electrode 7 such as an aluminum electrode on one surface thereof, and is resin-sealed by electrically connecting this electrode 7 and the bump-shaped metal protrusion 6 of the film carrier with ordinary adhesive. A semiconductor device of the present invention is obtained.

In FIG. 1, the material of the insulating film 2 is not limited as long as it has electrical insulation properties, such as polyester resin, epoxy resin, urethane resin, polystyrene resin, polyethylene resin, polyamide resin, etc.
Any thermosetting resin or thermoplastic resin can be used, such as polyester resin, ABS resin, polycarbonate resin, and silicone resin. Among these, it is preferable to use a polyide ξ-based resin from the viewpoint of heat resistance and mechanical strength.

The one-sided glue 3 of the insulating film 2 may be made of gold, for example.
It is formed of conductive materials such as various metals such as silver, copper, nickel, and cobalt, or various alloys containing these as main components, and includes a semiconductor element 1, an external connection electrode 7, a bump-shaped metal protrusion 6, and a metal substance 5. electrically connected via
Wiring is performed in a desired linear pattern so that the semiconductor element 1 can perform a predetermined function.

In the present invention, the through holes 4 provided in the insulating film 2 are important for achieving the connection between the leads 3 and the external connection electrodes 7 on the semiconductor element l, and are important for establishing connections between the leads 3 and the external connection electrodes 7 on the semiconductor element l. At least one fine through hole is provided in the thickness direction of the film 2 at a pitch smaller than the width of the lead 3 in the vicinity of the through hole 4. The holes can be formed with arbitrary hole diameters and hole pitches using a method such as etching. For example, it is preferable to perform drilling by irradiation with an excimer laser. In addition, the diameter of the through-holes 4 should be made large enough to prevent adjacent through-holes 4 from connecting with each other, and the pitch between the holes should be made as small as possible to increase the number of through-holes 4 in contact with the leads. This is preferable in order to reduce the electrical resistance of the metal substance to be filled in a later step.

Among the through holes 4 provided as described above, the leads 3
A conductive path is formed in the through hole in the contact area by filling it with a metal substance 5. Furthermore, several micrometers are added to the opening on the opposite side of the lead abutting surface of the through hole 4 where the conductive path is formed.
A protrusion 6 is formed in the shape of a bump with a height of m to several tens of μm.

The formation of conductive paths and bump-shaped metal protrusions using a metal material can be selectively performed only in the through-holes in the contact areas of the leads 3, for example, by electroplating using the leads 3 as electrodes.

Further, the metal substance 5 filled in and protruded from the through hole 4 is
The material is not limited to a single metal material, but can also have a multilayer structure using multiple types of metals. For example, as shown in FIG. 2, an inexpensive metal material 5a such as copper is used for the first layer on the side where the through hole is in contact with the glue, and the third layer in contact with the semiconductor element is made of a highly reliable metal material such as gold. The first layer and the third layer are made of metal material 5C.
As the second layer located between the N and N, nickel or the like may be used as a barrier metal material 5b to prevent mutual reaction between the metal materials forming the eleventh and third layers.

The thermoadhesive resin layer 8 used in the present invention is extremely important for improving the electrical, mechanical, and chemical reliability of semiconductor devices, and is made of thermosetting resin such as epoxy resin or fluorine-based resin. Any thermoplastic resin such as resin can be used. Specific examples include bolioid ξ-based resins, epoxy-based resins, silicone-based resins, and fluorine-based resins.

The resin layer 8 is formed by coating the entire surface or pattern of the bump-like metal protrusion-shaped bottom surface of the insulating film, or by placing a film or ribbon on the film.

FIGS. 3(a) to 3(e) are manufacturing process diagrams for connecting a film carrier and a semiconductor element to obtain a semiconductor device.

FIG. 3(a) is a cross-sectional view of the insulating film 2 with the through-hole 4 formed therein as described above, and FIG. , FIG. 3(C) is a cross-sectional view when the bump-shaped metal protrusion 6 is formed, and FIG.
b), FIG. 3(d) is a cross-sectional view when a heat-adhesive resin layer 8 is provided on the surface so as to cover the bump-shaped metal protrusion 6, and FIG. 3(e) is a perspective view of the semiconductor element 1. The thermoadhesive resin layer 8 covering the upper part of the bump-shaped metal protrusion 6 in FIG. 3(a), which shows a cross-sectional view of the semiconductor device after connection, expands during thermocompression bonding in FIG. 3(e). The external connection electrode 7 on the semiconductor element 1 and the bump-shaped metal protrusion 6 are electrically connected. Note that the heat-adhesive resin N8 does not necessarily have to be provided to cover the bump-shaped metal protrusion 6 as shown in FIG. It is a good thing.

When the semiconductor element 1 is connected to the film carrier with the heat-adhesive resin layer 8 interposed in this way, a layer of the heat-adhesive resin is formed between the carrier and the element, and even the through holes are filled with the resin. This improves adhesion and strengthens the electrical connection. Furthermore, since the surface of the semiconductor device can be protected by the resin layer, resin sealing can be performed at the same time as connection, and the manufacturing process can also be simplified. In addition, Fig. 3(d)
As shown in Figure 2, the excess resin flows into the through-holes that are not filled with metal material and pushes out the air inside, so there is no cranking caused by heating during connection, resulting in high reliability.

<Effects of the Invention> As described above, the film carrier of the present invention provides a through hole in the insulating film in the lead contact area or in the area and its vicinity, fills the inside with a metal substance, and further includes bumps. Since the shaped metal protrusion is formed, when forming the through hole, it is only necessary to roughly align it with the lead forming part.
In addition, the bump-like protrusions allow for highly accurate positioning of connections with semiconductor elements, thereby improving the reliability of the resulting semiconductor device.

In addition, highly accurate bumps can be formed at low cost, and by making the wiring and through-holes finer, it is possible to accommodate fine pitches of semiconductor element wiring. Furthermore, the external connection electrodes on the semiconductor element surface can be freely laid out within the element surface, increasing the degree of freedom in wiring design.

Furthermore, since the film carrier of the present invention is provided with a heat-adhesive resin layer on the connection surface, resin sealing can be performed at the same time when connecting to a semiconductor element, simplifying the manufacturing process and ensuring a strong connection. This will improve reliability.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an example of a semiconductor device using the film carrier of the present invention, FIG. 2 is an enlarged cross-sectional view of a through hole filled with a multilayer metal substance, and FIG. 3(a) ~
(e) is a manufacturing process diagram for connecting the semiconductor element 1 to a film carrier to obtain a semiconductor device. DESCRIPTION OF SYMBOLS 1... Semiconductor element, 2... wA edge film, 3...
...Lead, 4...Through hole, 5...Metal substance, 6...
... Bump-shaped metal protrusion, 7 ... External connection electrode, 8
...Thermoadhesive resin layer

Claims (4)

[Claims] (1) An insulating film having a plurality of fine through-holes in the thickness direction has a lead at an opening on one side, and a conduction path made of a metal material is formed only in the lead-forming through-hole, and the opening on the other side of the through-hole A film carrier comprising a bump-shaped metal protrusion formed on the insulating film, and a heat-adhesive resin layer formed on the surface of the insulating film on which the bump-shaped metal protrusion is formed. (2) The film carrier according to claim (1), wherein the conductive path is formed by filling with a metal substance. (3) The film carrier according to claim (1) or (2), wherein the conductive path is formed in a multilayer structure using a plurality of types of metal substances. (4) A semiconductor element having an electrode for external connection is claimed in claim (1)
) - (3) A semiconductor device connected to the bump-shaped metal protrusion according to any one of (3).