JP2883235B2 - Package for storing semiconductor elements - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a semiconductor device housing package for housing a semiconductor device.

[0002]

2. Description of the Related Art Conventionally, a semiconductor element housing package for housing a semiconductor element, particularly a semiconductor integrated circuit element such as an LSI, is generally made of an electrically insulating material such as alumina ceramics, and the semiconductor integrated circuit element is provided substantially at the center of the upper surface thereof. An insulating base having a metallized wiring layer made of a refractory metal powder of tungsten, molybdenum, manganese, or the like led out from the periphery of the recess to the outer peripheral end thereof, and a semiconductor integrated circuit element electrically connected to an external electric circuit. An external lead terminal brazed to the metallized wiring layer via a brazing material such as silver brazing to connect to the metallized wiring layer, and a metal lid body. And bonding each electrode of the semiconductor integrated circuit device to the metallized wiring layer via a bonding wire. Thereafter, a metal lid is welded to the upper surface of the insulating base, and the semiconductor integrated circuit element is hermetically sealed in a container formed of the insulating base and the metal lid, thereby obtaining a semiconductor device as a final product. .

In the conventional package for housing a semiconductor element, a metal frame 22 made of a metal material such as Kovar metal or 42 alloy is usually soldered to the upper surface of an insulating base 21 as shown in FIG. With a metal lid on the metal frame 22
The metal cover 23 is attached to the upper surface of the insulating base 21 by welding the base 23 by a seam welding method or the like, whereby the container including the insulating base 21 and the metal cover 23 is hermetically sealed.

[0004] In addition, the metal frame 23 is brazed to the insulating substrate 21 by first forming a metallized metal made of a refractory metal powder such as tungsten, molybdenum, or manganese on the upper surface of the insulating substrate 21 to have a slightly larger area than the metal frame 22. The layer 24 is formed by adopting a conventionally known thick film method such as a screen printing method, and then a brazing material 25 such as silver brazing and a metal frame 22 are sequentially placed on the metallized metal layer 24, Lastly, a temperature of about 800 ° C. is applied to the brazing material 25 to heat and melt the brazing material 25, and the entire surface of the metallized metal layer 24 and the metal frame in order to increase the bonding area and increase the bonding strength. This is done by spreading it sufficiently on the side bottom surface of the body 25.

[0005]

However, in this conventional package for housing a semiconductor element, the brazing material for brazing the metal frame to the insulating substrate has a thickness of 60.0 μm or more over the entire upper surface of the metallized metal layer formed on the insulating substrate. Of Kovar metal and 42 that make up the metal frame
Because the thermal expansion coefficient of the alloy and the thermal expansion coefficient of the silver brazing material constituting the brazing material are significantly different from the thermal expansion coefficient of the alumina ceramic constituting the insulating base, etc., a metal cover is attached to the brazing portion of the metal frame. When heat is applied when mounting the semiconductor integrated circuit element or when operating the semiconductor integrated circuit device, a large thermal stress is generated between the metal frame and the insulating base by the heat, and this is caused by the metallized metal layer. Has a drawback that the metallized metal layer is peeled off from the insulating substrate concentrated on the outer peripheral end.

For this reason, the conventional package for accommodating a semiconductor device has a low reliability of hermetic sealing inside the container, and cannot normally and stably operate the semiconductor integrated circuit device accommodated therein for a long period of time.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks, and an object of the present invention is to eliminate the occurrence of peeling in a metallized metal layer for brazing a metal frame provided on an insulating substrate. The reliability of hermetic sealing is high, and the semiconductor integrated circuit
Another object of the present invention is to provide a semiconductor element storage package that can be operated stably.

[0008]

According to the present invention, a metal frame is brazed to a metallized metal layer provided on the surface of an insulating substrate, a metal lid is attached to the metal frame, and a semiconductor element is mounted inside. A semiconductor element housing package adapted to be air-tightly housed, wherein a thickness of a brazing material for brazing the metal frame to the metallized metal layer is within a range of 0.3 mm from the outer peripheral end of the metallized metal layer. 30.0μm
It is characterized by the following.

[0009]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 and 2 show one embodiment of a package for housing a semiconductor element according to the present invention, wherein 1 is an insulating base, and 2 is a metal lid. The insulating base 1 and the metal lid 2 constitute a container 3 for housing the semiconductor integrated circuit device.

The insulating substrate 1 has a concave portion 1a for forming a space for accommodating the semiconductor integrated circuit element 4 in the center of the upper surface thereof.
A semiconductor integrated circuit element 4 is attached to the bottom of the recess 1a via an adhesive such as resin, glass, brazing material or the like.

The insulating substrate 1 is made of an electrically insulating material such as a sintered body of aluminum oxide, a sintered body of mullite, a sintered body of aluminum nitride, a sintered body of silicon carbide and the like. Alumina (Al ₂ O
₃ ), silica (SiO ₂ ), calcia (CaO), magnesia (M
gO) and the like, and an appropriate organic solvent and a solvent are added and mixed to form a slurry, and a ceramic green sheet (ceramic green sheet) is obtained by employing a conventionally known doctor blade method or a kander roll method. Thereafter, the ceramic green sheet is subjected to an appropriate punching process and a plurality of sheets are laminated, and a high temperature (about 1600 ° C.)
It is manufactured by firing at a temperature of

A metallized wiring layer 5 extending from the periphery of the concave portion 1a to the outside of the container 3 is formed on the insulating substrate 1, and a semiconductor integrated circuit element 4 is formed around the concave portion 1a of the metallized wiring layer 5. Are electrically connected via bonding wires 6, and external lead terminals 7 connected to an external electric circuit are attached to a portion led out of the container 3 via a brazing material such as silver brazing. Is done.

The metallized wiring layer 5 is made of tungsten
(W), molybdenum (Mo), a high melting point metal powder such as manganese (Mn), a suitable organic solvent to the high melting point metal powder such as tungsten, a metal paste obtained by adding a solvent and mixing the conventionally known metal paste. A thick film method such as a screen printing method is used, and is applied to a ceramic green sheet serving as the insulating substrate 1 in advance, so that the container 3 can be formed around the concave portion 1a of the insulating substrate 1.
To the outside of the substrate.

The metallized wiring layer 5 is coated with a metal having good conductivity and excellent corrosion resistance, such as nickel (Ni) or gold (Au), on the exposed surface by plating or the like to a thickness of 1.0 to 20.0 μm.
The metallized wiring layer 5 can be effectively prevented from being oxidized and corroded, and the connection between the metallized wiring layer 5 and the bonding wires 6 and the brazing between the metallized wiring layer 5 and the external lead terminals 7 can be effectively prevented. Attachment becomes extremely strong. Therefore, oxidation corrosion of the metallized wiring layer 5 is prevented, and the connection between the metallized wiring layer 5 and the bonding wires 6 and the metallized wiring layer 5 and the external lead terminals are prevented.
In order to make the brazing with the metal 7 firm, the exposed surface of the metallized wiring layer 5 is coated with nickel, gold or the like in an amount of 1.0 to 20.0.
It is preferable to coat the layer to a thickness of μm.

The external lead terminals 7 brazed and attached to the metallized wiring layer 5 serve to connect the semiconductor integrated circuit element 4 housed therein to an external electric circuit, and connect the external lead terminals 7 to the external electric circuit. As a result, the semiconductor integrated circuit element 4 accommodated therein is electrically connected to an external electric circuit via the metallized wiring layer 5 and the external lead terminals 7.

The external lead terminal 7 is made of Kovar metal (Fe-
Ni-Co alloys) and 42 alloys (Fe-Ni alloys), and other ingots such as Kovar metal are rolled and stamped using well-known metalworking methods. It is formed in a predetermined plate shape.

On the upper surface of the insulating base 1, a metallized metal layer 8 is adhered and formed.
A metal frame 9 is brazed through a brazing material 10 such as silver brazing.

The metallized metal layer 8 on the upper surface of the insulating substrate 1
Is composed of a high melting point metal powder such as tungsten, molybdenum, manganese, etc., and is obtained by mixing and adding a suitable organic solvent and a solvent to the high melting point metal powder such as tungsten, etc. The metal paste is printed and applied on the upper surface of the insulating substrate 1 by employing a conventionally known screen printing method, and is baked at a high temperature to be formed on the upper surface of the insulating substrate 1.

The metallized metal layer 8 has a surface coated with a metal having good wettability and excellent corrosion resistance with a brazing material 10 such as nickel (Ni) or gold (Au) by a plating method or the like.
When the metallized metal layer 8 is layered to a thickness of μm, oxidation corrosion of the metallized metal layer 8 can be effectively prevented, and the brazing attachment between the metallized metal layer 8 and the metal frame 9 can be made extremely strong. it can. Therefore, the metallized metal layer
It is preferable to coat a metal having good wettability with the brazing material and excellent corrosion resistance to a thickness of 1.0 to 20.0 μm on the surface of No. 8.

A metal frame 9 brazed to the metallized metal layer 8 via a brazing material 10 acts as a base metal member when the metal cover 2 is attached to the insulating base 1, and the metal frame 9 The metal cover 2 is attached to the insulating base 1 by welding the metal cover 2 to the base 9 by a seam welding method or the like. The metal frame 9 is made of a metal material such as Kovar metal or 42 alloy, and is made of an ingot of the Kovar metal or the like.
Is formed into a predetermined frame shape by employing a conventionally known metal working method such as a rolling method or a punching method.

The metal frame 9 is formed on a metallized metal layer 8 adhered on the upper surface of the insulating base 1 on a brazing material 10 such as silver brazing.
And a metal frame 9 are sequentially placed thereon, and then the preform made of the brazing material 10 is heated and melted to be brazed to the upper surface of the insulating base 1.

Further, as shown in FIG. 2, the metal frame 9 has a metallized metal layer 8 of a brazing material 10 for brazing the metal frame 9.
Is brazed onto the metallized metal layer 8 so that the thickness of the metallized metal layer 8 is 30.0 μm or less in a range T of 0.3 mm from the outer peripheral edge of the metallized metal layer 8. Since the thickness of the material 10 is small, the thermal stress generated between the metal frame 9 and the insulating substrate 1 due to the difference in thermal expansion coefficient between the insulating substrate 1, the metal frame 9 and the brazing material 10 is reduced by the metallized metal layer. The metallized metal layer 8 does not concentrate on the outer peripheral end of the metallized metal layer 8 but escapes to the surface of the metallized metal layer 8 so that the metallized metal layer 8 does not peel off from the insulating substrate 1.

The method of reducing the thickness of the brazing material 10 to which the metal frame 9 is brazed at the outer peripheral end of the metallized metal layer 8 is to increase the area of the metallized metal layer 8 and to reduce the heat melting temperature of the brazing material 10. And the molten brazing material is prevented from spreading significantly on the metallized metal layer 8.

The brazing material for brazing the metal frame 9
In the range T where the thickness of the metallized metal layer 8 is 0.3 mm from the outer peripheral edge of the metallized metal layer 8 to the metallized metal layer 8.
If it exceeds 30.0 μm, the thermal stress generated due to the difference in the thermal expansion coefficient between the insulating base 1 and the metal frame 9 and the brazing material 10 concentrates on the outer peripheral edge of the metallized metal layer 8 and Is separated from the insulating base 1. Accordingly, a range T of 0.3 mm from the outer peripheral edge of the metallized metal
In this case, the thickness of the brazing material 10 to be applied must be 30.0 μm or less.

Thus, according to the package for accommodating a semiconductor device of the present invention, the semiconductor integrated circuit device 4 is attached to the bottom surface of the concave portion 1a of the insulating base 1 via an adhesive, and each electrode of the semiconductor integrated circuit device 4 is metallized wiring layer. 5 through a bonding wire 6 and then electrically insulated.
A metal lid 9 is welded to a metal frame 9 brazed to the upper surface of the substrate 1 by a seam welding method or the like, and the semiconductor integrated circuit element 4 is hermetically sealed inside a container 3 comprising an insulating base 1 and a metal lid 2. By sealing, a semiconductor device as a final product is obtained.

It should be noted that the present invention is not limited to the above-described embodiment, and various changes can be made without departing from the gist of the present invention.

[0027]

According to the present invention, a metal frame is brazed to a metallized metal layer provided on the surface of an insulating base, and the thickness of the brazing material for brazing the metal frame to the metallized metal layer is reduced. Inside the outer edge of the layer
Since the thickness is less than 30.0μm in the range of 0.3mm, the thermal stress generated between the metal frame and the insulating substrate due to the difference in the thermal expansion coefficient between the insulating frame, the metal frame and the brazing material is metallized. The metallized metal layer escapes to the surface of the metallized metal layer without concentrating on the outer peripheral edge, and as a result, the metallized metal layer can be extremely firmly adhered to the insulating substrate without any peeling off from the insulating substrate. .

Therefore, the semiconductor element housing package of the present invention has high reliability of hermetic sealing of a container formed of an insulating base and a metal lid, and allows the semiconductor integrated circuit element housed therein to be normally and for a long period of time. It can be operated stably.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a semiconductor element storage package according to the present invention.

FIG. 2 is an enlarged sectional view of a main part of the package shown in FIG.

FIG. 3 is an enlarged sectional view of a main part of a conventional package for housing a semiconductor element.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating base 2 ... Metal lid 3 ... Container 5 ... Metallized wiring layer 7 ... External lead terminal 8 ... Metallized Metal layer 9 Metal frame 10 Brazing material

Claims (1)

(57) [Claims] 1. A metal frame is brazed to a metallized metal layer provided on the surface of an insulating substrate, and a metal lid is attached to the metal frame so as to hermetically accommodate a semiconductor element therein. A package for semiconductor element storage according to claim 1, wherein the thickness of the brazing material for brazing the metal frame to the metallized metal layer is 0.
A package for housing a semiconductor device, wherein the thickness is 30.0 μm or less in a range of 3 mm.