JPH0752760B2 - Package for semiconductor device - Google Patents

Description

The present invention relates to a structural improvement of a high-frequency semiconductor device package in which the inside of the package is electromagnetically shielded from the outside, and the reliability of a small-sized high-frequency semiconductor device package having an electromagnetic shield is described. The inner surface of the side wall with a material (such as silicon dioxide, silicon nitride, or polyimide) that is hard to adhere to for the purpose of improving the properties and improving the manufacturing yield. Is composed of.

[Industrial application field]

The present invention relates to a structural improvement of a high frequency semiconductor device package in which the inside of the package is electromagnetically shielded from the outside.

[Conventional technology]

The semiconductor device is used by being put in some package for the purposes of (a) protection from an external atmosphere, (b) mechanical fixation, (c) electrical extraction to the outside, and (d) heat dissipation.

Although there are various models of semiconductor device packages according to the related art, two examples according to the related art of the present invention will be briefly described below.

First Example In FIG. 5, a frame-shaped ceramic plate 11 having an opening in a central portion (semiconductor chip mounting region) is placed on a peripheral region on a stem 1 made of a rectangular metal plate, and a screen is placed thereon. An input / output lead section 4 is provided which is made of a metallized layer formed by printing a film made of a conductive material such as a metal paste using a printing method. A semiconductor chip 6 is fixed to a central region on the stem 1 with a metal braze 8 such as gold tin braze, and is connected to the input / output lead portion 4 with a bonding wire 7. Further, a side wall 2 of a rectangular cylindrical body made of a ceramic material is provided as a side wall surrounding the semiconductor chip 6 on the stem 1, and an inner wall 21 of the side wall 2 is provided with a metallized layer 5 for electromagnetic shielding. There is. The upper opening of the side wall 2 made of a ceramic material is covered with a metal cap (top portion) 3 and sealed with a metal braze 8 such as gold tin braze.

Second Example In FIG. 6, the side wall of the package is composed of a rectangular metal tubular body 9 for electromagnetic shielding. Other configurations are
In addition to the fact that the electromagnetic shield made of the metallized layer 5 is unnecessary,
It is almost the same as the first example.

In particular, in the case of a high frequency semiconductor device used in the gigahertz order, it is necessary to protect the semiconductor device from noise radio waves. It is desirable to do.

Further, in a high frequency semiconductor device used in the gigahertz order, it is necessary to particularly increase the gain, and for that purpose, it is necessary to reduce the dielectric loss of the package. Therefore, it is desirable to downsize the package. This is because the dielectric loss depends on the volume of the dielectric.

[Problems to be solved by the invention]

By the way, in order to seal a semiconductor device package having an electromagnetic shield, the side wall 2 and the cap (top portion) 3 are made of metal brazing such as gold tin brazing as shown by 8 in FIGS. 5 and 6. Since the metal braze and the metallized layer 5 or the metal body 9 have good wettability and easily adhere to each other, the metal braze is shown in FIG.
As shown by, it flows down along the inner surfaces of the side walls 2 and 9,
The bonding wire 7 may be blown out or the bonding wire 7 may be short-circuited, which has the drawbacks that the reliability is likely to decrease and the manufacturing yield is likely to decrease.

An object of the present invention is to solve this drawback, and to improve the reliability of a small-sized high-frequency semiconductor device package having an electromagnetic shield and improving the manufacturing yield.

[Means for Solving the Problems] The above object is to provide a side wall (2) having a metallized portion for electromagnetic shielding inside, the side wall (2) and the metal brazing (8).
In a package for a semiconductor device having a top portion (3) adhered via, a metallized portion of a side wall (2) is
This is achieved by a package for a semiconductor device in which a film (10) of a material to which the metal brazing (8) is hard to adhere, for example, silicon dioxide, silicon nitride or polyimide is formed.

[Action]

In the semiconductor device package according to the present invention, the inner surface of the side walls 2 and 9 is made of a film of a material to which liquid metal is unlikely to adhere.
Since the coating film 10 is formed, the coating film 10 prevents the metal brazing material 8 from flowing down, prevents the bonding wire 7 from being cut off, or prevents the bonding wire 7 from short-circuiting. It is possible to improve the reliability of the semiconductor device package and improve the manufacturing yield.

〔Example〕

Hereinafter, a semiconductor device package according to an embodiment of the present invention will be further described with reference to the drawings.

First, as shown in FIG. 2, a frame-shaped ceramic plate 11 having an opening in the central portion (semiconductor chip mounting region) is placed on the peripheral region on the stem 1 made of a rectangular metal plate, and then, A screen made of a conductive material such as a metal paste is printed by using a screen printing method to form the input / output lead portion 4 made of a metallized layer.

Next, as shown in FIG. 3, a metallized layer 5 is formed on the inner surface of the rectangular cylindrical body 2 made of a ceramic material for electromagnetic shielding and placed on the stem 1. At this time, it is necessary to leave a space between the lower end of the metallized layer 5 and the lower surface of the rectangular tubular body 2. This is to ensure insulation from the input / output lead section 4.

Next, as shown in FIG. 4, a coating 10 made of a material to which a liquid metal does not easily adhere, such as silicon dioxide, silicon nitride, or polyimide, is formed on the inner surface of the metallized layer 5.

Next, as shown in FIG. 1, the semiconductor chip 6 is fixed with a metal braze 8 such as gold-tin braze, and a bonding wire 7 is held.
It is connected to the input / output lead section 4. Finally, the upper opening is covered with a metal cap (top portion) 3, and a metal braze 8 such as gold tin braze is used.
Seal with.

In the cap sealing process of the semiconductor device package according to the present embodiment, a material formed on the inner surface of the metallized layer 5 to which a liquid metal is hard to adhere, for example, a film such as silicon dioxide, silicon nitride, or polyimide. Since the metal braze is prevented from flowing down by 10, the cutting of the bonding wire 7 or the short-circuiting of the bonding wire 7 is effectively prevented.

〔The invention's effect〕

As described above, in the high-frequency semiconductor device package in which at least the side wall and the top are electromagnetically shielded from the outside according to the present invention, the inner surface of the side wall is a material in which the metal brazing is difficult to adhere, for example, Since the coating of silicon dioxide, silicon nitride, or polyimide is formed, the metal brazing such as gold tin brazing for sealing the side wall and the top does not flow down along the inner surface of the side wall, and the bonding wire is It does not melt and does not short-circuit the bonding wire.

Therefore, it is possible to improve the reliability of a small-sized high-frequency semiconductor device package having an electromagnetic shield and improve the manufacturing yield.

[Brief description of drawings]

FIG. 1 is a sectional view of a semiconductor device package according to an embodiment of the present invention. 2 to 4 are process diagrams of a semiconductor device package according to an embodiment of the present invention. 5 and 6 are cross-sectional views of a semiconductor device package according to the related art. FIG. 7 is a cross-sectional view showing a defect (a metal braze flow-down state in a semiconductor device package) according to the conventional technique. 1 ... Stem (metal), 11 ... Ceramic plate, 2 ... Side wall (ceramic), 21 ... Side wall inner surface, 3 ... Top part (metal cap), 4 ... Input / output lead part, 5 ... Metallization Layer, 6 ... Semiconductor chip, 7 ... Bonding wire, 8 ... Metal brazing, 9 ... Sidewall (metal), 10 ... Coating made of material with low wettability, 81 ... Metal brazing.

Claims (2)

[Claims] 1. A semiconductor device having a side wall (2) having a metallized portion for electromagnetic shielding inside and a top portion (3) adhered to the side wall (2) through a metal brazing (8). In the package, the metal brazing (8) is provided on the metallized portion of the side wall (2).
A semiconductor device package, characterized in that a film (10) of a material that does not easily adhere is formed. 2. The semiconductor device package according to claim 1, wherein the material of the film (10) is silicon dioxide, silicon nitride, or polyimide.