JPH10144828A - Semiconductor package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin semiconductor package at low cost. SOLUTION: In a semiconductor package 10, a pattern-formed lead frame 3 and a semiconductor element 1 are connected through the intermediary of metallic balls 2. After forming a stress buffer 5 so as to cover the semiconductor element 1 and the metallic balls 2, the whole body is sealed up with a resin 4. At this time, the stress buffer 5 is made of a material such as silicone, etc., capable of easing external compression-expansion stress. In such a constitution, the stress imposed on junction parts 2a due to the thermal expansion, etc., resultant from the thermal contraction of resin and the temperature rise in a product application in the case of the shifting over from high to low temperature after the sealing up with the resin 4 can be absorbed through the intermediary of the stress buffer 5, thereby enabling the thin semiconductor package to be manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor package using metal balls for connecting a lead frame and a semiconductor element.

[0002]

2. Description of the Related Art Conventionally, in a semiconductor package 20 using a lead frame 3 as shown in FIG.
The semiconductor element 1 was joined to the substrate a, and the electrode portion of the semiconductor element 1 and the lead frame 3 were electrically connected via the thin metal wire 6 and sealed with the resin 4. Also, as shown in FIG.
In the AB conductor package 30, the electrode portion of the semiconductor element 1 and the inner lead 7a are electrically connected via a metal bump or a metal ball 2, and a liquid resin 4a is dropped and sealed around the periphery.

[0003]

By the way, as shown in FIG. 4, in order to electrically connect the electrode portion of the semiconductor element and the lead frame 3 via the thin metal wire 6, a rising height of the thin metal wire is provided. However, there is a problem that the resin portion cannot be made thin. When a TAB tape is used as shown in FIG. 5, there is a problem that the external dimensions are not stable because the liquid resin 4a is dropped and sealed as a package. Further, the use of TAB tapes has a problem that the production cost is high. Therefore, an object of the present invention is to provide a semiconductor package that is thin and can be manufactured at low cost.

[0004]

According to the first aspect of the present invention, an electrode formed on a semiconductor element and a connecting portion of a lead frame are connected via a metal ball. In the semiconductor package connected and resin-sealed, the semiconductor package has a configuration in which a stress buffer is provided around the connection portion. According to the invention of claim 2, the stress buffer is a metal ball. According to the third aspect of the present invention, the stress buffering material covers at least the bonding portion of the metal ball. According to the invention as set forth in claim 4, metal balls are bonded to both surfaces of the lead frame, and semiconductor elements having electrode portions formed on the respective surfaces of the metal balls are bonded to each other. In the semiconductor package,
It has a configuration in which a stress buffer is provided between each semiconductor element.

[0005] By having each of these components, heat shrinkage of the resin at the time of transition from high temperature to normal temperature after resin sealing,
The stress on the joint due to thermal expansion or the like due to a rise in temperature during use of the product can be absorbed via the stress buffer, and a thin semiconductor package can be manufactured.

[0006]

FIG. 1 shows a first embodiment of the present invention.
This will be described with reference to FIG. FIG. 1 is a cross-sectional view of the semiconductor package according to the first embodiment. As shown in FIG. 1, in a semiconductor package 10 according to a first embodiment of the present invention, a lead frame 3 on which a pattern is formed and a semiconductor element 1 are connected via a metal ball 2, and a stress buffer 5 Are formed so as to cover the semiconductor element 1 and the metal ball 2 described above, and are then sealed with a resin 4.

Here, as shown in FIG.
Is made of a material such as silicone which can relieve external compression / expansion stress.

[0010] According to the present embodiment configured as described above, the resin is sealed by heat shrinkage at the time of transition from a high temperature to a normal temperature after the resin encapsulation, bonding by thermal expansion accompanying a rise in temperature during use of the product, and the like. The stress on the portion 2a can be absorbed through the stress buffer 5, and a thin semiconductor package can be manufactured.

Next, a second embodiment of the present invention will be described with reference to FIG. The difference from the first embodiment is that
The point is that the stress buffer 5 is provided only near the joint 2a.

According to the present embodiment configured as described above, the stress buffering material 5 is provided only in the vicinity of the joint 2a so that the stress buffering material can be used while reducing the amount of stress buffering material used. Can be.

Next, a third embodiment of the present invention will be described with reference to FIG. The difference from the first embodiment is that
Metal balls 2 are provided on both sides of a lead frame 3 on which a pattern is formed.
Are connected to both sides, and the stress buffer 5
a, 2b and between the semiconductor elements 1, 1a.

According to the present embodiment configured as described above, the stress in the joints 2a and 2b can be reduced by filling the stress buffer 5 between the semiconductor elements 1 and 1a. .

[0013]

As described above, according to the invention described in the claims of the present application, a metal ball is used for electrical connection between a semiconductor element and a lead frame, and a stress buffer is provided around the metal ball. Thus, a thin and low-cost semiconductor package can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a semiconductor package according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a semiconductor package according to a second embodiment of the present invention.

FIG. 3 is a sectional view of a semiconductor package according to a third embodiment of the present invention.

FIG. 4 is a cross-sectional view of a conventional semiconductor package.

FIG. 5 is a sectional view of a conventional semiconductor package.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 semiconductor element 1a semiconductor element 2 metal ball 2a joint 2b joint 3 lead frame 3a island 4 resin 4a resin 5 stress buffer 6 thin metal wire 7 film carrier 7a inner lead 10 semiconductor package 20 conventional semiconductor package 30 TAB Semiconductor package

Claims (4)

[Claims] An electrode formed on a semiconductor element and a connection portion of a lead frame are connected via a metal ball, and a resin-sealed semiconductor package is provided with a stress buffer around the connection portion. A semiconductor package characterized by the above-mentioned. 2. The semiconductor package according to claim 1, wherein said stress buffering material covers a joint portion of the metal ball and an entire circuit portion of the semiconductor element. 3. The semiconductor package according to claim 1, wherein said stress buffering material covers at least a joint of the metal balls. 4. In a semiconductor package in which metal balls are bonded to both surfaces of a lead frame, and semiconductor elements having electrode portions formed on the respective surfaces of the metal balls are bonded to each other, a stress buffer is provided between the semiconductor elements. A semiconductor package characterized in that: