JPH0714942A - Semiconductor device - Google Patents

Abstract

PURPOSE:To provide a semiconductor device in which a semispherical bump can be formed easily on the opening of a conductor through-hole which is to be connected with a conductor pattern prepared in a package body. CONSTITUTION:The semiconductor device is provided with a semiconductor chip which is mounted on a plastic package body 10 having a conductor pattern thereon. In a conductor through-hole 22 which is formed by connecting a conductor layer 24 that has an opening on one end face of the body 10 and is formed along the inside wall face thereof with the conductor pattern, the stem part 30 of a T-shaped metallic pin erected on a collar part 26 whose area is larger than the opening is inserted as being contact with the layer 24, and a semispherical bump 18 is formed on the flat face side of the part 26 covering the opening of the through-hole 22.

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 semiconductor chip mounted on a package having a conductor pattern formed thereon.

[0002]

2. Description of the Related Art Conventionally, the semiconductor device shown in FIG. 3 has been used. In the semiconductor device shown in FIG. 3, the semiconductor chip 104 mounted in the cavity recess 102 of the package body 100 in which a conductor pattern (not shown) is formed is connected to the conductor pattern by a wire 106, and the package body 100 is also connected. The conductor pattern formed on the pin 11 is attached to the pin 11 mounted on the bottom surface of the package body 100.
0 and vias and the like are connected. It should be noted that the semiconductor chip 104 and the like are covered by the cap 108 with the cavity recess 10
It is sealed within 2. Conventionally, such a package body 1
00 was made of ceramics, but the present inventor previously proposed a plastic package in Japanese Patent Application No. 5-16934 in order to reduce the weight of the semiconductor device and reduce the manufacturing cost.

In this plastic package,
As in a ceramic package, the conductor pattern and the pin cannot be connected by the via that is formed by filling the paste in which the metal powder is mixed into the through hole formed in the green sheet and firing it. As shown in FIG. The conductor pattern is connected to the pin 110 by the conductor through hole 202. The conductor through hole 202 is formed by forming a conductor layer 206, which is connected to a conductor pattern by plating, on the inner wall surface of the through hole 204 formed in the plastic package body 200 by a drill or the like. still,
The conductor layer 20 is formed around the opening of the conductor through hole 202.
A terminal land 207 connected to the conductor 6 is formed in series with the conductor layer 206. In this conductor through hole 202,
The pins 110 with the long pin portions 211 and the short pin portions 212 protruding are attached to each of both surfaces of the flange portion 210 having an area larger than the opening area. The pin 110 is usually attached by fitting by inserting the short pin portion 212 into the conductor through hole 202, or by using both the fitting and resin attachment.

In the pin 110 thus mounted in the conductor through hole 202, the short pin portion 212 inserted in the conductor through hole 202 contacts the conductor layer 206, and the terminal land 207 contacts the flange portion 210. Is connected to the conductor pattern formed on the plastic package body 200. However, recently, as the operation speed of the semiconductor chip 104 mounted on the package body 200 has been increased, the inductance and resistance of the long pin portion 211 of the pin 110 protruding outward from the bottom surface of the package body 200. Has become a problem. For this reason, the inventor has proposed that the pin 110
We also proposed to use hemispherical bumps instead of.

[0005]

By using a bump instead of the pin 110, the long pin portion 2 of the pin 110 can be obtained.
It is possible to eliminate the influence of the inductance, resistance, etc. of 11. However, when a bump is used instead of the pin 110, a low melting point metal such as solder is melted and a hemispherical shape is formed on the opening of the conductor through hole 202 or in the vicinity thereof by utilizing the surface tension of the molten low melting point metal. It is necessary to form bumps. Therefore, various problems shown in FIG. 5 occur.

That is, as shown in FIG. 5A, when the bump 300 is not formed on the terminal land 207 while avoiding the opening of the conductor through hole 202, the hemispherical bump 3 is formed.
00 can be easily formed, but the area of the terminal land 207 must be increased, and the formation density of the bumps 300 becomes lower than the mounting density of the conventional pins 110. On the other hand, if the bumps 300 are not formed directly on the openings of the conductor through-holes 202, as shown in FIG. 5B, the bumps 300 whose shape has collapsed due to a portion of the low melting point metal entering the conductor through-holes 202. Is formed. Alternatively,
As shown in FIG. 5C, the low melting point metal flows along the periphery of the opening of the conductor through hole 202 to form a donut-shaped bump 300. In this way, the conductor through hole 20
It was extremely difficult to form a hemispherical bump on the second opening. Therefore, an object of the present invention is to provide a semiconductor device capable of easily forming a hemispherical bump on an opening of a conductor through hole connected to a conductor pattern formed on a package body.

[0007]

As a result of repeated studies to achieve the above object, the present inventor has used a T-shaped pin in which a pin portion is erected on a collar portion, and uses the T-shaped pin's pin portion as a conductor. By inserting into the through hole and forming a bump on the flat surface side of the collar portion of the T-shaped pin that covers the opening of the conductor through hole,
The inventors have found that hemispherical bumps can be easily formed on the openings of conductor through holes, and have reached the present invention. That is, according to the present invention, in a semiconductor device in which a semiconductor chip is mounted on a package body having a conductor pattern formed thereon, a conductor layer formed along one inner wall surface of the package body and formed along an inner wall surface is formed on the conductor pattern. Into the conductor through-hole formed by connection, a pin portion of a metal T-shaped pin erected on a collar portion having an area larger than the opening area of the conductor through hole is inserted so as to come into contact with the conductor layer. In addition, a hemispherical bump made of a low melting point metal such as solder is formed on the flat surface side of the collar portion of the T-shaped pin that covers the opening of the conductor through hole. is there. The present invention having such a configuration can be suitably applied to a semiconductor device whose package body is made of plastic.

[0008]

According to the present invention, since the opening of the conductor through hole connected to the conductor pattern of the package body is covered with the flange of the T-shaped pin, solder or the like is not formed on the bump forming surface of the flange which is a flat surface. When the low melting point metal is melted to form a hemispherical bump, the low melting point metal may enter into the conductor through hole, or the low melting point metal may flow in a donut shape along the opening edge of the conductor through hole. It is possible to prevent and easily form a hemispherical bump. Further, since the bump can be formed on the opening of the conductor through hole, the density of the bump can be increased.

[0009]

The present invention will be described in more detail with reference to the drawings.
FIG. 1 is a sectional view showing an embodiment of the present invention.
The semiconductor chip 12 mounted in the cavity concave portion 11 (which may be referred to as “”) is bonded by a wire 14 to a conductor pattern (not shown) formed on the package body 10. The cavity recess 11 in which these semiconductor chips 12 and the like are mounted is sealed in the cavity recess 11 by the cap 16. The conductor pattern of the package body 10 shown in FIG.
Hemispherical solder bumps 18, 18 formed on the bottom surface of the
.. are connected by the conductor through holes 22 shown in FIG.

The conductor through-hole 22 shown in FIG. 2 is formed along the inner wall surface of the through-hole 22 by copper plating or the like after the through-hole 20 that comes into contact with the conductor pattern formed on the package body 10 is drilled. To form the conductor layer 24. The conductor layer 24 connects the conductor pattern and the terminal land 26 formed on the periphery of the opening of the through hole 22. Such conductor through hole 22
By inserting the pin portion 30 of the T-shaped pin made of metal, the collar portion 26 covers the opening of the conductor through hole 22 and the T-shaped pin is mounted on the bottom surface of the package body 10. This T-shaped pin has a pin portion 30 and a conductor layer 24.
The conductor pattern formed on the package body 10 is connected to the conductor pattern by the contact with the flange 28 and the terminal land 26. The T-shaped pin used in this embodiment is
It can be formed of copper, nickel, iron-nickel-cobalt alloy, iron-nickel alloy, or the like, and is mounted on the package body 10 by fitting the conductor through hole 22 and the pin portion 30. If the conductor through hole 22 and the pin portion 30 are not sufficiently fitted to each other, resin may be applied.

In this embodiment, the package body 10
On the flat side of the collar 26 of the T-pin attached to the bottom of the
A hemispherical solder bump 18 is formed. This bump 18
First, the flux is applied to the bump forming surface, which is a flat surface of the collar portion 26, and then the solder balls are placed on the bump forming surface to be melted by heating, and the surface tension of the molten solder is used to make a hemispherical shape. And Next, the hemispherical bumps 18 are formed by cooling the hemispherical molten solder.
As another forming method, a solder paste may be applied to the bump forming surface of the collar portion 26 by screen printing to a predetermined thickness to form a solder paste layer, and then the solder paste layer may be heated and melted to form a hemispherical shape. The bump 18 can be formed.

Thus, the solder bumps 18 of this embodiment are
Is formed on the flat surface side of the collar portion 26 of the T-shaped pin that covers the opening of the conductor through hole 22, so that the influence of the opening of the conductor through hole 22 can be eliminated when the bump 18 is formed, and the hemisphere Shaped bumps 18 can be easily formed. Further, the bumps 18 can be formed on the openings of the conductor through holes 22, and the bumps 18 can be provided on the bottom surface of the package body 10 with high density. Therefore, it is possible to cope with the increase in the number of pins of the semiconductor device accompanying the high integration of the semiconductor chip 12. Further, in a package in which the conductor pattern of the package body 10 and the external connection terminals are connected via the conductor through holes 22, the influence of inductance, resistance, etc. is greater than that of a conventional pin used as an external connection terminal. It is possible to easily form a small number of bumps 18 and mount a semiconductor chip having an increased operation speed.

The T-shaped pin used in this embodiment described above is the short pin portion 212 of the pin 110 shown in FIG.
Of the long pin portion 211 protruding outward from the bottom surface of the package body 10 after inserting into the conductor through hole 22.
May be cut. Although the plastic package 10 has been described in the present embodiment, when the conductor through hole is provided in the ceramic package as well, the T-shaped pin used in the present embodiment is used to form the conductor through hole on the opening. Moreover, hemispherical bumps can be easily formed.

[0014]

According to the present invention, hemispherical bumps, which are less affected by inductance and resistance as compared with the conventional pins, can be easily formed on one end surface of the package body, and the operation speed is increased. A semiconductor device equipped with a chip can be provided.

[Brief description of drawings]

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

2 is a partial cross-sectional view showing a structure near a bump 18 of the semiconductor device shown in FIG.

FIG. 3 is a cross-sectional view for explaining a conventional semiconductor device.

4 is a partial cross-sectional view showing a structure near a pin 110 of the semiconductor device shown in FIG.

FIG. 5 is an explanatory diagram for explaining a problem that occurs when forming the bumps 300 in the conductor through holes 202.

[Explanation of symbols]

 10 Package Body 12 Semiconductor Chip 18 Bump 22 Conductor Through Hole 24 Conductor Layer 28 Collar Section 30 Pin Section

Claims (2)

[Claims] 1. In a semiconductor device in which a semiconductor chip is mounted on a package body having a conductor pattern formed thereon, a conductor layer formed along an inner wall surface of the package body and connected to the conductor pattern. Into the conductor through-hole formed as described above, the pin portion of the metal T-shaped pin erected on the flange portion having an area larger than the opening area of the conductor through hole is inserted so as to contact the conductor layer. In addition, a hemispherical bump made of a low melting point metal such as solder is formed on the flat surface side of the collar portion of the T-shaped pin that covers the opening of the conductor through hole. 2. The semiconductor device according to claim 1, wherein the package body is made of plastic.