JPH09213744A - Semiconductor device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a possible short circuit by solder on the occasion of mounting a package by flip chip connection, and besides to narrow the pitch between electrodes. SOLUTION: Electrodes 2 of a package 1 wherein a semiconductor device is sealed with resin, and through holes bored at the corresponding parts to the electrodes 4 of a printed board 3 are provided, and a film 6 filled with low-melting-point metal 5 is inserted between the package 1 and the printed board 3, and mounting is performed. Besides, the width of the opening ends of the through holes of the film 6 is made larger than that of the central parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device, and more particularly to a semiconductor device having a package mounted by flip chip connection and a method for manufacturing the same.

[0002]

2. Description of the Related Art A conventional semiconductor device and its manufacturing method will be described with reference to FIG. FIG. 4 is a sectional view of a conventional semiconductor device. Conventionally, LGA (Land Grid Array)
), A BGA (Ball Grid Array), or other semiconductor device using a package, a solder ball 15 is formed on the electrode portion 12 on the back surface of the package 11,
A so-called flip-chip connection is used in which the package 11 is directly mounted on the printed circuit board 13 by soldering at a position corresponding to the third electrode portion 14.

[0003]

In the method of mounting the package 11 using the solder balls 15, the step of attaching the solder balls 15 to the electrode portions 12 of the package 11 and then connecting the solder balls 15 to the electrode portions 14 of the printed circuit board 13 is required. Since it is necessary, there is a problem that it takes time.

Further, as seen in the explanatory view showing an example of the problem in the conventional semiconductor device of FIG. 5, there is a possibility that the solder ball 15 is crushed during mounting and comes into contact with the adjacent solder ball 15 to cause a short circuit. Therefore, the adjacent electrode portions 1
Since the space between the two must be widened, there is a problem that the narrowing of the pitch is limited.

In view of the above circumstances, the present invention provides a semiconductor device which simplifies the process when mounting a package by flip-chip connection and can realize a narrow pitch between electrodes. Has an aim.

[0006]

In order to achieve the above object, a semiconductor device of the present invention comprises a package in which a semiconductor element is sealed, a printed board on which the package is mounted,
It is characterized in that it is provided between the printed board and the package, and is provided with a film having a through hole at a portion to be connected to the electrode of the printed board and the electrode of the package.

Further, the through hole of the film is filled with a low melting point metal. Furthermore,
The width of the opening of the through hole is preferably wider than the width of the central portion.

Further, a step of forming a through hole in a portion of the film to be connected between the electrode of the printed board and the electrode of the package of the film inserted between the printed board and the package, and filling the through hole with a low melting point metal. And a step of aligning the package and the film,
A semiconductor device comprising: a step of aligning the film and the printed circuit board; and a step of connecting the aligned package and the printed circuit board with a low melting point metal through the film. There is a manufacturing method of.

[0009]

DETAILED DESCRIPTION OF THE INVENTION A semiconductor device and a method of manufacturing the same according to embodiments of the present invention will be described below with reference to the drawings. 1 is a sectional view of a semiconductor device according to a first embodiment of the present invention, FIG. 2A is a perspective view of a film used in the first embodiment of the present invention, and FIG. It is sectional drawing of the film of FIG.

The film 6 is made of a non-conductive and heat-resistant material such as polyimide having a thickness of about 1 mil. Film 6
First, a through hole 7 having the same width is formed from the front side to the back side by press working at a position corresponding to the electrodes 2 and 4 of the package 1 and the printed circuit board 3, and then a mask having a hole larger than the through hole 7 is formed. Is covered on the film 6 and an etching process is performed to widen the opening end. After that, through hole 7
The solder 5 is made to flow from above and below so that the ends of the solder balls 5 on both sides come out from the surface of the film 6.

A mark for alignment is attached to the film 6 processed as described above. Similarly, a mark for alignment is also attached to the package 1 and the printed circuit board 3, and the position is detected by using a laser, for example, and the electrodes 1 and 4 of the package 1 and the printed circuit board 3 are aligned with each other. Then, heat is applied to melt the solder 5, and the electrode portion 2 of the package 1 and the electrode portion 4 of the printed board 3 are electrically connected via the film 6.

As a result, the step of attaching the solder balls 5 to the electrode portions 2 of the package 1 is not necessary, and the film 6 filled with the solder 5 is attached to the package 1 and the printed circuit board 3.
Since it can be replaced with a process of inserting the device in between, the efficiency is improved and the assembly process time is shortened.

Further, by widening the opening end, the solder 5 flows into the opening end space of the film 6 even if the solder 5 is crushed at the time of mounting, and there is no fear of contact with the adjacent solder 5, so that a short circuit due to the solder 5 occurs. Can be prevented.

Next, a semiconductor device according to a second embodiment of the present invention and a method of manufacturing the same will be described with reference to FIGS. First, the outer size of the film 6 is formed to be the same as the outer size of the package 1. A mask having a hole of an arbitrary size is covered on the film 6 at a position corresponding to the electrodes 1 and 4 of the package 1 and the printed circuit board 3, and an etching process is performed to form a through hole 7 having the same width from the front side to the back side. . After that, a mask having a hole larger than the through hole 7 is covered and etching is performed again to widen the opening end of the through hole 7. Further, the center of the through hole 7 is filled with the solder 5, and then the solder balls 5 are formed from above and below to complete the filling of the solder 5.

Next, a frame is formed for alignment, the film 6 and the package 1 are aligned and fixed in the frame, and the film 6 and the package 1 are placed on the printed circuit board 3 and heat-treated. The portion 2 and the electrode portion 4 of the printed circuit board 3 are electrically connected via the film 6.

As a method for filling the through holes 7 of the film 6 with the solder 5, there is a method of forming the film 6 into a three-layer structure, which will be described with reference to the drawings. FIG. 3 is a manufacturing process diagram of a modified example of the film used in the present invention.

First, as shown in FIGS. 3A and 3B, the package 1 of the film 6a and the printed circuit board 3 are formed.
Through holes 7 of the same width are formed from the front side to the back side by press working at the locations corresponding to the electrode portions 2 and 4. Next, FIG.
As shown in FIG. 3C, the through hole 7 is filled with Cu, and
As shown in (d), the film 6a is covered with the films 6b and 6c from above and below. Covered films 6b and 6c
Then, as shown in FIGS. 3 (e) and 3 (f), an etching process is performed by the same method as in the first embodiment to form the solder 5 in the opening.

In the manufacturing process shown in FIG. 3, etching treatment is performed in advance on the portions of the films 6b and 6c corresponding to the package 1 and the electrode portions 2 and 4 of the printed circuit board 3, and then the film 6a is removed from above and below. There is also a method of covering 6b and 6c.

As a method of aligning the film 6, the package 1 and the printed circuit board 3, a guide pin is erected on the substrate 3 and the film 6 and the package 1 are sequentially fixed along the guide pin and heat is applied. There is also a method of electrically connecting the electrodes 1 and 4 of the package 1 and the printed circuit board 3 by adding.

The present invention is not limited to the first and second embodiments described above, and the method of processing the through hole 7 of the film 6 and the method of aligning the film 6, the package 1 and the printed circuit board 3 are different from each other. A combination may be used.

The present invention is not limited to the first and second embodiments described above, and the film 6 can use epoxy resin, fluororesin, glass epoxy, polyester instead of polyimide. Further, instead of the solder 5, Cu, Al, which is a low melting point metal, is used to electrically connect the electrode portion 2 of the package 1 and the electrode portion 4 of the printed board 3.
You may use Au, Ni, etc.

The shape of the holes in the film 6 is shown in FIG.
The shape is not limited to the shape shown in FIG. 1, and any shape is possible as long as the opening end has a spread. The package 1 of the present invention is not limited to plastic resin, and ceramic may be used.

[0023]

According to the present invention, by connecting the package and the electrode portion of the printed circuit board through the film having the through hole filled with solder, solder which may occur when the package is mounted by flip chip connection It is possible to prevent a short circuit due to, and to narrow the pitch between the electrodes.

[Brief description of drawings]

FIG. 1 is a sectional view of a semiconductor device according to an embodiment of the present invention.

FIG. 2 (a) is a perspective view of a film used in an example of the present invention. (B) It is sectional drawing of the film of (a).

FIG. 3 is an explanatory diagram of a manufacturing process of a modified example of the film used in the present invention.

FIG. 4 is a sectional view of a conventional semiconductor device.

FIG. 5 is an explanatory diagram showing an example of problems in a conventional semiconductor device.

[Explanation of symbols]

1, 11 ... Package, 2, 12 ... Package electrode part, 3, 13 ... Substrate, 4, 14 ... Substrate electrode part, 5, 1
5 ... Solder, 6, 6a, 6b, 6c ... Film, 7 ... Through hole, 8 ... Cu

Claims (4)

[Claims] 1. A package encapsulating a semiconductor element, a printed circuit board on which the package is mounted, and a package which is inserted between the printed circuit board and the package and which connects the electrode of the printed circuit board and the electrode of the package. A semiconductor device, comprising: a film having a through hole in an intended portion. 2. The semiconductor device according to claim 1, wherein the through hole of the film is filled with a low melting point metal. 3. The semiconductor device according to claim 1, wherein a width of an opening end of the through hole is wider than a width of a central portion of the through hole. 4. A step of forming a through hole in a portion of the film to be inserted between the printed board and the package, where the electrode of the printed board and the electrode of the package are to be connected, and the through hole is filled with a low melting point metal. The step of aligning the package and the film, the step of aligning the film and the printed circuit board, and the package and the printed circuit board that have been aligned via the film. And a step of connecting with a melting point metal.