JP2552419Y2 - 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 package for accommodating a semiconductor element, particularly a semiconductor integrated circuit element, is as shown in FIG.
An insulating base 11 made of an electrically insulating material such as alumina ceramics, having a concave portion for forming a cavity for accommodating a semiconductor element in a central portion, and a low-melting glass layer 12 for sealing applied on an upper surface; A lid body also made of an electrically insulating material such as alumina ceramics, having a recess in the center for forming a cavity for accommodating a semiconductor element, and a low-melting glass layer 14 for sealing adhered to the lower surface. 13 and the semiconductor element housed inside
And an external lead terminal 16 for electrically connecting the external lead circuit 15 to an external electric circuit.The external lead terminal 16 is placed on the upper surface of the insulating base 11 and is sealed in advance. The external lead terminal 16 is temporarily fixed to the insulating base 11 by melting the low melting point glass layer 12 of FIG. Output electrode) to the external lead terminal 16 via the bonding wire 17, and then
The low-melting glass layers 12 and 14 for sealing in which the insulating base 11 and the lid 13 are adhered to the respective main surfaces facing each other are fused and integrated, and the insulating base 11 and the lid 13 are separated from each other. A semiconductor device as a product is obtained by hermetically sealing the container.

The low-melting glass layers 12 and 14 for sealing, which are attached to the upper surface of the insulating base 11 and the lower surface of the lid 13, are made of the insulating base 11 and the lid 13. Glass whose thermal expansion coefficient matches the thermal expansion coefficient of alumina ceramics, etc., to firmly adhere to, for example, lead oxide (PbO) 70.0
Wt%, boron oxide (B ₂ O ₃ ) 8.6 wt%, titanium oxide (T
Glass containing 7.8% by weight of iO ₂ ) and 6.7% by weight of zirconium oxide (ZrO ₂ ) is used.

[0004]

[Problems to be solved by the invention] However, recently,
Information processing devices such as IC cards are rapidly becoming thinner, and semiconductor devices mounted on the information processing devices are required to have a reduced thickness. It has been required to reduce the thickness of the package as a whole by making the thickness of the lid about 0.2 mm.

[0005] Therefore, when the thickness of the lid of the above-mentioned conventional package for housing a semiconductor element is set to about 0.2 mm and the thickness of the entire package is reduced, the lid of the package is usually made of an electrically insulating material such as alumina ceramics. Since alumina ceramics are fragile and have low mechanical strength, reducing the thickness of the lid significantly reduces the mechanical strength of the lid, and as a result, the semiconductor element is placed inside the container consisting of the insulating base and the lid. After hermetically sealing and forming a semiconductor device,
When an external force is applied to the lid, the lid is easily damaged by the external force, and the hermetic sealing of the inside of the container is broken, and the semiconductor element housed therein cannot be operated normally and stably for a long period of time. Had the disadvantage that

In order to solve the above-mentioned drawbacks, it is considered that the lid is made of Kovar metal or 42 alloy which has excellent mechanical strength and a thermal expansion coefficient similar to that of the insulating base and the low melting point glass layer for sealing. Can be

However, Kovar metal and 42 alloy have a slight difference in thermal expansion coefficient from those of alumina ceramics and low-melting glass for sealing which constitute an insulating base (Kovar metal and 42 alloy: 4.4 alloy). ~ 5.0 ×
10 ⁻⁶ / ° C., alumina ceramics and low melting glass for sealing: 6.5 to 7.5 × 10 ⁻⁶ / ° C.), when the Kovar metal or 42 alloy is used for a large-area lid, the thermal expansion coefficient When the melting point of the low-melting glass layer for sealing is melted and the container formed of the insulating base and the lid is hermetically sealed, the heat for melting the low-melting glass for sealing is generated by the lid. When applied to both the insulating substrate and the low-melting glass layer for sealing, cracks and cracks may occur in the low-melting glass layer for sealing, Peeling occurs between the low melting glass layer and the lid,
As a result, the hermetic sealing of the container is broken, and this causes a disadvantage that the semiconductor element housed therein cannot be operated normally and stably for a long period of time.

[0008]

According to the present invention, a semiconductor element and an external lead terminal to which each electrode of the semiconductor element is connected by a bonding wire are sandwiched between an insulating base and a metal lid, and a sealing member is provided. In a semiconductor element housing package in which a semiconductor element is hermetically sealed inside by glass welding of glass, one main surface of the metal lid has a flat area of 0.04 to
A plurality of recesses having a thickness of 4.0 mm ² and a depth of 25.0 to 75.0% with respect to the thickness of the lid are formed so that the total area of the recesses is 10.0 to 50.0% of the planar area of the lid. It is assumed that.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the accompanying drawings.

FIGS. 1 and 2 show an embodiment of a package for accommodating a semiconductor device according to the present invention, wherein 1 is an insulating base and 2 is a lid. The insulating base 1 and the lid 2 constitute a container for housing the semiconductor element 3.

The insulating substrate 1 is made of an electrically insulating material such as alumina ceramics, and has a semiconductor element in the center of its upper surface.
The semiconductor device 3 is attached and fixed to the bottom surface of the recess 1a via an adhesive such as glass, resin, brazing material, or the like.

The insulating substrate 1 is made of, for example, aluminum oxide (Al ₂ O ₃ ), silica (SiO ₂ ), magnesia (MgO),
Raw material powder such as calcia (CaO) is charged into a press die corresponding to the shape of the insulating substrate 1 shown in Fig. 1 and molded by applying a constant pressure, and then the molded product is fired at a temperature of about 15000 ° C. It is produced by doing.

On the upper surface of the insulating base 1, one end of an external lead terminal 4 made of a metal such as Kovar metal (Fe-Ni-Co alloy) or 42 alloy (Fe-Ni alloy) has a low melting point glass for sealing.
The external lead terminal 4 is temporarily fixed via a metal plate 5 and is formed by forming an ingot (lumps) of Kovar metal or the like into a predetermined plate shape by employing a conventionally known rolling and punching method. .

The external lead terminal 4 serves to connect the semiconductor element 3 housed therein to an external electric circuit, and one end of each of the electrodes of the semiconductor element 3 is provided with a bonding wire 6.
The semiconductor element 3 is electrically connected to the external electric circuit by connecting the external lead terminal 4 to the external electric circuit.

The external lead terminal 4 may be formed by plating a metal having good conductivity and excellent corrosion resistance made of nickel, gold or the like to a thickness of 1.0 to 20.0 μm by plating. 4 can be effectively prevented and the electrical connection between the external lead terminals 4 and the bonding wires 6 and the external electric circuit can be made good. Therefore, it is preferable that nickel, gold or the like be layered on the surface of the external lead terminal 4 by plating to a thickness of 1.0 to 20.0 μm.

The sealing low-melting glass 5 for temporarily fixing the external lead terminals 4 to the insulating base 1 is made of, for example, lead oxide (Pb
O) 75.0% by weight, titanium oxide (TiO ₂ ) 9.0% by weight, boron oxide (B ₂ O ₃ ) 7.5% by weight, zinc oxide (ZnO) 2.0% by weight. The glass paste obtained by adding and mixing is applied by printing to a predetermined thickness on the upper surface of the insulating substrate 1 by a conventionally known screen printing method,
Thereafter, this is baked at a temperature of about 400 ° C. to be attached to a predetermined position on the upper surface of the insulating substrate 1. As a method of temporarily fixing the external lead terminals 4 to the upper surface of the insulating base 1 using the low melting glass 5, one end of the external lead terminals 4 is placed on the low melting glass 5 attached to the upper surface of the insulating base 1. This is carried out by mounting and then heating it to a temperature of about 400 ° C. to heat and melt the low-melting glass 5.

The insulating base 1 to which the external lead terminals 4 are temporarily fixed is also provided with a lid 2 on the upper surface thereof, a sealing low-melting glass 7 adhered to the lower surface of the lid 2 and the insulating base 1. The low-melting glass for sealing 5 adhered to the upper surface is joined by melting and integrating, thereby forming the insulating base 1 and the lid.
The semiconductor element 3 is hermetically sealed inside the container composed of

The lid 2 is made of an iron alloy such as Kovar metal (Fe-Ni-Co alloy) or 42 alloy (Fe-Ni alloy).
The ingot (lumps) of the Kovar metal or the like is manufactured by forming a predetermined plate shape using a conventionally known metal rolling method and a punching method.

Since the iron alloy constituting the lid 2 is not a brittle material such as alumina ceramics, its thickness is 0.2 mm.
It is not damaged even when the external force is applied. Therefore, even if the thickness of the lid 2 is set to about 0.2 mm and the overall thickness of the package is reduced, the hermetic sealing inside the container can be maintained, and the semiconductor element 3 accommodated in the container can be normally and stably maintained for a long time. It can be activated.

The lid 2 has a flat surface of 0.04
To 4.0 mm ² , the depth is 25.0 to 75.0 with respect to the thickness of the lid 2.
%, The elastic modulus of the lid 2 is greatly improved by the concave A, whereby the low-melting glass 5, 7 for sealing is melted, and the insulating base 1 and the lid are removed. When hermetically sealing the container composed of the body 2, heat for melting the low melting point glass 5, 7 for sealing is applied to both the lid 2, the insulating base 1, and the low melting point glass 5, 7 for sealing. Even if the thermal stress generated between them is absorbed by deforming the lid 2, cracks and cracks may occur in the low-melting glass for sealing 5, 7 or the low-melting glass for sealing 5 ,
No peeling occurs between 7 and the lid 2.

When the plane area of the recess A formed in the cover ^{2 is} less than 0.04 mm ² or more than 4.0 mm ² , the cover A
2, the effect of improving the elastic modulus (stress relaxation effect) becomes poor, and it becomes impossible to completely absorb the thermal stress generated between the lid 2 and the insulating base 1 and the low-melting-point glasses 5, 7. Therefore, each recess A formed in the lid 2 has a flat area.
Specified in 0.04 to 4.0 mm ^2.

If the depth of the recess A is less than 25.0% of the thickness of the lid 2, the effect of improving the elastic modulus (stress relaxation effect) of the lid 2 becomes poor.
The mechanical strength of 2 is greatly reduced. Therefore, the concave
The depth of A is specified in the range of 25.0 to 75.0% with respect to the thickness of the lid 2.

Further, when the total area of the recesses A is less than 10.0% with respect to the area of the cover 2, the effect of improving the elastic modulus (stress relaxation effect) of the cover 2 becomes poor, and exceeds 50.0%. Then, the mechanical strength of the lid 2 is greatly reduced.
Therefore, the sum of the plane areas of the recesses A is specified in the range of 10.0 to 50.0% with respect to the plane area of the lid 2.

Further, when the surface of the lid 2 is coated with high-melting glass, the high-melting glass serves to electrically insulate the lid 2 which is conductive, and the lid 2 is provided with a semiconductor element 3. When the bonding wire 6 connecting the electrode to the external lead terminal 4 comes into contact, a short circuit may occur between the electrodes of the semiconductor element 3 or unnecessary electricity may flow from the outside to the semiconductor element 3 to cause a change in the characteristics of the semiconductor element 3. Can be effectively prevented.
Therefore, in order to operate the semiconductor element 3 with high reliability and stability, it is preferable to cover the surface of the lid 2 with high melting point glass.

Examples of the high melting point glass covering the surface of the lid 2 include 40.0 to 60.0% by weight of lead oxide (PbO), 20.0 to 40.0% by weight of silicon oxide (SiO ₂ ), and boron oxide (B ₂
O ₃ ) glass containing 5.0 to 10.0% by weight, or silicon oxide (SiO ₂ ) 40.0 to 60.0% by weight, barium oxide (BaO) 20.
0 to 35.0% by weight, calcium oxide (CaO) 5.0 to 15.0
The glass containing by weight is preferably used because it has a thermal expansion coefficient close to the thermal expansion coefficient of the lid 2 and allows the lid 2 to be firmly covered.

The high melting point glass having the above composition has a melting point of
When the insulating base 1 and the lid 2 are joined by heating and melting the low-melting glass 5 and 7 for sealing, the low-melting glass 5 and 7 for sealing are heated to the high-melting glass because the temperature is as high as 600 to 900 ° C. Even if heat for melting is applied, it does not melt, and the electrical insulation of the lid 2 can be maintained.

The low-melting glass 7 for sealing adhered to the lower surface of the lid 2 is, for example, the same glass as the low-melting glass 5 for sealing adhered to the upper surface of the insulating base 1, that is, lead oxide (PbO) 75.0 wt%, titanium oxide (TiO ₂₎ 9.0 wt%, boron oxide (B ₂ O ₃₎ 7.5 wt%, zinc oxide (ZnO) 2.0 wt%
Is used, and is adhered to the lower surface of the lid 2 by the same method as the method of attaching the low-melting glass 5 for sealing to the upper surface of the insulating substrate 1.

The sealing low-melting glass 7 adhered to the lower surface of the lid 2 is melted and integrated with the sealing low-melting glass 5 adhered to the upper surface of the insulating substrate 1 to form an insulating substrate. 1 and the lid 2 are joined to each other, so that the semiconductor element 3 is hermetically sealed in a container including the insulating base 1 and the lid 2.

Thus, according to the package for housing a semiconductor element of the present invention, the semiconductor element 3
And the semiconductor element 3
External terminals with bonding wires 6
4, and then the insulating base 1 and the lid 2 are heated and melted, and the low-melting-point glasses 5 and 7 for sealing, which have been previously adhered to the opposing main surfaces thereof, are joined together. As a result, the semiconductor element 3 is hermetically sealed inside the container including the insulating base 1 and the lid 2, thereby completing the semiconductor device as a product.

[0030]

[Effects of the Invention] According to the package for storing a semiconductor element of the present invention, the plane area of one main surface of the metal lid is 0.04 to 4.0 mm.
² , a plurality of recesses having a depth of 25.0 to 75.0% of the thickness of the lid, and the total area of the recesses is 10.0 to 5 times the planar area of the lid.
The elasticity of the lid is greatly improved because it is formed to be 0.0%. When the low-melting glass for sealing is melted and the container consisting of the insulating base and the lid is hermetically sealed, Even if heat for melting the low-melting glass for stopping is applied to both the lid, the insulating substrate, and the low-melting glass for sealing, the thermal stress generated between the two is absorbed by deforming the lid. As a result, cracks and cracks do not occur in the low-melting glass for sealing, and peeling does not occur between the low-melting glass for sealing and the lid, and the container is hermetically sealed. And the semiconductor element housed therein can be operated normally and stably for a long period of time.

Further, since the thickness of the lid can be reduced, the overall thickness of the package can be reduced, so that the present invention can be applied to a semiconductor device mounted on an information processing device which has recently become thinner.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an embodiment of a package for housing a semiconductor device according to the present invention;

FIG. 2 is a plan view of the lid of the package shown in FIG. 1 as viewed from the lower surface side.

FIG. 3 is a sectional view showing an embodiment of a conventional package for housing a semiconductor element.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating base 2 ... Metal cover 3 ... Semiconductor element 4 ... External lead terminal 5, 7 ... Low melting glass for sealing A ... Concavity

Claims (1)

(57) [Scope of request for utility model registration] 1. A sandwich the external lead terminals each electrode of the semiconductor element and the semiconductor element are connected by a bonding wire between the insulating substrate and the metallic lid, inside the glass fusing glass for sealing In the semiconductor element housing package for hermetically sealing a semiconductor element, a recess having a plane area of 0.04 to 4.0 mm ² and a depth of 25.0 to 75.0% of the thickness of the lid is formed on one main surface of the metal lid. A semiconductor element storage package, wherein a plurality of the recesses are formed so that the sum of the plane areas of the recesses is 10.0 to 50.0% of the plane area of the lid.