JP3176250B2 - 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 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 such as an LSI (Large Scale Integrated Circuit) is usually made of an electrically insulating material such as an aluminum oxide sintered body. An insulating base having a recess for accommodating a semiconductor element in a substantially central portion and a plurality of metallized wiring layers made of a high melting point metal powder of tungsten, molybdenum, manganese or the like led out from the periphery of the recess to the outer periphery; A plurality of external lead terminals brazed to the metallized wiring layer via a brazing material such as silver brazing in order to electrically connect to an external electric circuit, such as an iron-nickel-cobalt alloy or an iron-nickel alloy. A semiconductor element is bonded and fixed to the bottom surface of the concave portion of the insulating base via an adhesive such as glass, resin, and brazing material. Then, each electrode of the semiconductor element is connected to a metallized wiring layer via a bonding wire, and thereafter, a metal lid is welded to the upper surface of the insulating base, and the semiconductor element is placed inside a container comprising the insulating base and the metal lid. Is airtightly accommodated to form a semiconductor device as a final product.

In the above-described conventional package for housing a semiconductor element, a metal frame made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy is usually brazed on the upper surface of an insulating base, and the metal frame is formed. The metal lid is attached to the upper surface of the insulating base by welding the metal lid to the frame by a seam welding method or the like, whereby the container including the insulating base and the metal lid is hermetically sealed. You.

[0004] In addition, the metal frame is brazed to the insulating base by first forming a frame-shaped metallized metal layer made of a refractory metal powder of tungsten, molybdenum, manganese or the like on the upper surface of the insulating base and around the recess for accommodating the semiconductor element. Is formed by employing a conventionally known thick film method such as a screen printing method, and then a brazing material such as a silver brazing material and a metal frame are sequentially placed on the frame-shaped metallized metal layer. Then, a temperature of about 800 ° C. is applied to the brazing material, and the brazing material is heated and melted.

[0005]

However, recently,
With the expansion of the application field of the semiconductor element, the shape of the semiconductor element has become larger than before, and accordingly, the concave portion of the insulating base and the metal frame brazed around the concave portion have an extremely large shape. Because the metal frame has a rectangular cross section, high rigidity, and a slightly different coefficient of thermal expansion between the metal lid and the insulating base, the metal frame is composed of the insulating base and the metal lid. After the semiconductor element is hermetically housed inside the container to form a semiconductor device, when heat is applied to the metal lid and the insulating base, a difference in the thermal expansion coefficient between the metal lid and the insulating base results. When the thermal stress is generated and applied to the metal frame, the metal frame is detached from the insulating substrate together with the metallized metal layer formed on the insulating substrate, and the metal frame is cracked or cracked in the insulating substrate to which the metal frame is attached. Cracks Hermetic seal is torn of the container, as a result,
There has been a disadvantage that the semiconductor element housed in the container cannot be operated normally and stably for a long period of time.

[0006]

SUMMARY OF THE INVENTION The present invention has been devised in view of the above-mentioned drawbacks, and has as its object to complete a hermetic sealing of a container composed of an insulating base and a metal lid, and to provide a large-sized semiconductor device accommodated therein. An object of the present invention is to provide a semiconductor element housing package that can be operated normally and stably for a long period of time.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided an insulating substrate having a concave portion for accommodating a semiconductor element on an upper surface, a frame-shaped metallized metal layer surrounding the concave portion, and a brazing metal layer on the frame-shaped metallized metal layer. A semiconductor element storage package comprising a metal frame to be attached and a metal lid attached to the metal frame, wherein the metal frame is provided with flanges above and below legs. It has a substantially U-shape, and has legs of the metal frame.
The length L and the thickness T of the portion are set to 2 ≦ L / T ≦ 25.
The joint angle between the leg and the collar is a circle with a radius of 0.05 mm or more.
It is characterized by having an arc shape .

[0008]

[0009]

[0010]

According to the semiconductor device housing package of the present invention, a metal frame brazed to the frame-shaped metallized metal layer attached to the insulating base is provided with flanges on the upper and lower sides of the legs, and the cross section of the metal frame is substantially the same. Because of the letter-shaped shape, the metal frame is provided with spring properties.As a result, after the semiconductor element is hermetically housed in a container formed of an insulating base and a metal lid, the semiconductor device is formed.
Even if heat is applied to both the metal lid and the insulating base and thermal stress is generated between the two, the thermal stress is absorbed by the spring properties of the metal frame, thereby forming the metal frame on the insulating base. The semiconductor element to be housed inside the container with the hermetic sealing of the container completely completed without the metallized metal layer being detached from the insulating substrate together with the metallized metal layer and without the occurrence of cracks or cracks in the insulating substrate to which the metal frame is attached. It is possible to operate normally and stably for a long time.

According to the package for housing a semiconductor element of the present invention, the length L and the thickness T of the leg of the metal frame are set to 2 ≦ L /
If T ≦ 25, the spring properties of the metal frame become moderate,
The thermal stress generated due to the difference in thermal expansion coefficient between the metal lid and the insulating base can be completely absorbed by the metal frame.

Further, according to the package for housing a semiconductor element of the present invention, the joint corner between the leg and the flange of the metal frame has a radius of 0.1 mm.
When the metal frame is formed in an arc shape of not less than 05 mm , when the metal frame is brazed to the metallized metal layer adhered to the insulating base via the brazing material, the brazing material flows uniformly over the entire circumference of the metal frame, The brazing strength of the body can be increased.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 and 2 show an embodiment of a package for accommodating a semiconductor element according to the present invention, wherein 1 is an insulating base, and 2 is a metal lid. The insulating element 1 and the metal lid 2 make the semiconductor element 3
The container for accommodating is comprised.

The insulating substrate 1 is made of an electrically insulating material such as an aluminum oxide sintered body, a mullite sintered body, an aluminum nitride sintered body, a silicon carbide sintered body, a glass ceramic sintered body, and the like. A recess 1a is formed at a substantially central portion of the recess to form a space for accommodating the semiconductor element 3,
A semiconductor element 3 is bonded and fixed to the bottom of the recess 1a via an adhesive such as brazing material, glass, resin, or the like.

When the insulating substrate 1 is made of, for example, an aluminum oxide sintered body, a raw material powder of aluminum oxide, silicon oxide, magnesium oxide, calcium oxide or the like is mixed with a suitable organic binder, a solvent, etc., and mixed to form a slurry. In addition, this is formed into a sheet by a well-known doctor blade method, calender roll method, or the like to obtain a ceramic green sheet (ceramic raw sheet). Are laminated at a high temperature (about 160
(0 ° C.).

A plurality of metallized wiring layers 4 are formed on the insulating substrate 1 from the periphery of the concave portion 1a to the outer peripheral edge, and each electrode of the semiconductor element 3 is provided around the concave portion 1a of the metallized wiring layer 4. Are electrically connected via bonding wires 5, and external lead terminals 6 are brazed through brazing materials to portions led out to the outer peripheral edge of the insulating base 1.

The metallized wiring layer 4 provided on the insulating base 1 is made of a high melting point metal powder such as tungsten, molybdenum, manganese or the like, and the metallized wiring layer 4 is connected to an external lead terminal 6 connected to an external electric circuit. Has the function of electrically conducting the respective electrodes.

The metallized wiring layer 4 is prepared by screen-printing a metal paste obtained by adding a suitable organic solvent and a solvent to a refractory metal powder such as tungsten, for example, on a ceramic green sheet serving as the insulating substrate 1 in advance. By printing and applying a predetermined pattern by the method, the insulating substrate 1 is adhered and formed at a predetermined position.

The metallized wiring layer 4 is coated with a metal having excellent corrosion resistance, such as nickel and gold, and a good wettability with a brazing material to a thickness of 1 to 20 μm on the exposed surface by plating. In addition, the oxidation corrosion of the metallized wiring layer 4 can be effectively prevented, and the brazing connection between the metallized wiring layer 4 and the bonding wires 5 and the external lead terminals 6 can be made strong. Therefore,
It is preferable that a metal having excellent corrosion resistance, such as nickel and gold, and having good wettability with the brazing material is applied to the surface of the metallized wiring layer 4 to a thickness of 1 to 20 μm by plating.

The external lead terminals 6 brazed to the metallized wiring layer 4 adhered to the insulating base 1 are made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy. It acts to electrically connect to an external electrical circuit.

The external lead terminal 6 is formed by forming an ingot (lumps) such as an iron-nickel-cobalt alloy into a predetermined plate shape by using a conventionally known metal working method such as a rolling method or a punching method. Be produced.

On the other hand, a metallized metal layer 7 is formed on the upper surface of the insulating base 1 so as to surround the recess 1a for accommodating the semiconductor element 3, and the metallized metal layer 7 is formed in a frame shape. A metal frame 8 is brazed to 7 via a brazing material 9.

The frame-shaped metallized metal layer 7 functions as a base metal layer when the metal frame 8 is brazed to the insulating base 1, and is formed of a high melting point metal powder such as tungsten, molybdenum, and manganese.

The frame-shaped metallized metal layer 7 is insulated from a metal paste obtained by adding a suitable organic solvent and a solvent to a refractory metal powder such as tungsten and mixing the same method as the metallized wiring layer 4. The ceramic green sheet serving as the base 1 is previously applied in a predetermined pattern by a well-known screen printing method so as to be formed in a frame shape on the upper surface of the insulating base 1.

The frame-shaped metallized metal layer 7 is further provided with a metal frame 8 on its upper surface, and the metal frame 8 is provided with flanges 8b and 8c above and below a leg 8a as shown in FIG. Is provided, and has a substantially U-shaped cross section.

The metal frame 2 functions as a base metal member when the metal lid 2 is attached to the insulating base 1, and the flange 8b
Is attached to the upper surface of the insulating substrate 1 by brazing a metallized metal layer 7 adhered to the upper surface of the insulating substrate 1 via a brazing material 9 such as silver brazing, and a metal lid is provided on the flange portion 8c. 2 is attached by welding such as a seam welding method.

The cross section of the metal frame 2 is substantially U-shaped, and the leg 8a is provided with a spring property so that the flange 8
c, the metal lid 2 is welded, and the semiconductor element 3 is hermetically housed in a container including the insulating base 1 and the metal lid 2 to form a semiconductor device. Even if heat is applied to both of them and a thermal stress is generated between the two, the thermal stress is absorbed by the resiliency of the metal frame 8, whereby the metallized metal is formed on the insulating substrate 1. The semiconductor element 3 accommodated in the container without completely separating from the insulating substrate 1 together with the layer 7 and without causing cracks or cracks in the insulating substrate 1 to which the metal frame 2 is attached is completely hermetically sealed. Can operate normally and stably over a long period of time.

If the length L and the thickness T of the legs 8a are set to 2 ≦ L / T ≦ 25, the metal frame 8 has an appropriate spring property, and Even if thermal stress is generated between the insulating bases 1 due to the difference in thermal expansion coefficient between the two, the thermal stress can be completely absorbed by the metal frame 2, whereby the insulating base 1 and the metal lid The reliability of hermetic sealing of the container comprising the body 2 can be made extremely high. Therefore, it is preferable that the length L and the thickness T of the leg portion 8a of the metal frame 8 be set to 2 ≦ L / T ≦ 25.

The metal frame 8 has a leg 8a and a flange 8a.
If the joining corners a of b and 8c are formed in an arc shape having a radius of 0.05 mm or more, a brazing material 9 such as silver brazing is applied to the metallized metal layer 7 in which the flange 8b of the metal frame 8 is adhered to the insulating base 1. When brazing is performed through the metal frame 8, the brazing material 9 flows evenly over the entire surface of the metal frame 8, and the brazing strength of the metal frame 8 becomes strong. Therefore, in the metal frame 8, it is preferable that a joint corner a between the leg 8a and the flanges 8b and 8c is formed in an arc shape having a radius of 0.05 mm or more.

The metal frame 8 is made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy, and is subjected to a predetermined metal working on an ingot such as the iron-nickel-cobalt alloy. It is formed in a U-shaped cross section.

Thus, according to the above-described package for accommodating a semiconductor element, the semiconductor element 3
Is bonded and fixed via an adhesive such as brazing material, glass, resin and the like, and each electrode of the semiconductor element 3 is electrically connected to the metallized wiring layer 4 via a bonding wire 5. The metal cover 2 is welded to the flange 8c of the metal frame 8 brazed to the upper surface by a seam welding method or the like, and the semiconductor element 3 is hermetically accommodated in a container including the insulating base 1 and the metal cover 2. By doing so, a semiconductor device as a final product is obtained.

The present invention is not limited to the above-described semiconductor device housing package, and various modifications can be made without departing from the scope of the present invention.

[0033]

According to the package for housing a semiconductor element of the present invention, the metal frame brazed to the frame-shaped metallized metal layer attached to the insulating base is provided with flanges on the upper and lower sides of the legs.
Since the metal frame body is provided with resiliency due to the substantially U-shaped cross section, as a result, after the semiconductor element is hermetically housed inside a container formed of an insulating base and a metal lid, a semiconductor device is formed. Even if heat is applied to both the metal lid and the insulating base and thermal stress is generated between the two, the thermal stress is absorbed by the spring properties of the metal frame, thereby forming the metal frame on the insulating base. The semiconductor element to be housed inside the container with the hermetic sealing of the container completely completed without the metallized metal layer being detached from the insulating substrate together with the metallized metal layer and without the occurrence of cracks or cracks in the insulating substrate to which the metal frame is attached. It is possible to operate normally and stably for a long time.

Further, according to the semiconductor device housing package of the present invention, the length L and the thickness T of the leg of the metal frame are set to 2 ≦ L /
If T ≦ 25, the spring properties of the metal frame become moderate,
The thermal stress generated due to the difference in thermal expansion coefficient between the metal lid and the insulating base can be completely absorbed by the metal frame.

Further, according to the semiconductor element housing package of the present invention, the joint corner between the leg and the flange of the metal frame has a radius of 0.1 mm.
When the metal frame is formed in an arc shape of not less than 05 mm , when the metal frame is brazed to the metallized metal layer adhered to the insulating base via the brazing material, the brazing material flows uniformly over the entire circumference of the metal frame, The brazing strength of the body can be increased.

[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.

2 is an enlarged cross-sectional view of a main part of the package for housing a semiconductor element shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating base 1a ... Depression 2 ... Metal lid 3 ... Semiconductor element 4 ... Metallized wiring layer 6 ... ... External lead terminals 7 ... Frame-shaped metallized metal layer 8 ... Metal frame 8a ... Legs 8b, 8c ... Flange 9 ...・ Braze material

Claims (1)

(57) [Claims] An insulating base having a concave portion for accommodating a semiconductor element on an upper surface, a frame-shaped metallized metal layer surrounding the concave portion, and a metal frame brazed to the frame-shaped metallized metal layer. And a metal lid attached to the metal frame, wherein the metal frame has a substantially U-shaped cross section in which flanges are provided above and below the legs. And the length L and thickness T of the legs of the metal frame are 2
≤ L / T ≤ 25 and the joint corner between the leg and the flange
Characterized by having an arc shape with a radius of 0.05 mm or more.
Semiconductor device package .