JPH0410646A - Package for housing glass-sealed semiconductor element - Google Patents

Abstract

PURPOSE:To prevent a crack from being produced even under a sverere condition in a high-temperature atmosphere, provide perfect air-tight sealing, and make it possible to normally and stably operate a semiconductor element for a long time by using crystalline glass of a specified composition as glass members to fix external lead terminals to the upper face of an insulating substrate. CONSTITUTION:Recesses to contain a semiconductor element 3 are made in the center of an insulating substrate 1 and the center of a lid 2 and the semiconductor element 3 is fastened to the bottom of the recess 1a of the insulating substrate 1 with bond such as a brazing filler material. One end of each metallic external lead terminal 4 is fixed to the upper face of the insulating substrate 1 with glass members 5 and the electrodes of the semiconductor element 3 are electrically connected to the external lead terminals 4 with wires 6. The glass members 5 to fix the external lead terminals 4 to the upper face of the insulating substrate 1 are made of crystal glass composed of 55.0-60.0wt.% lead oxide, 7.0-11.0wt.% silicon oxide, 5.5-9.5wt.% boron oxide, 0.2-3.0wt.% aluminum oxide, and 20.0-30.0wt.% zinc oxide and are not softened and molten after crystallization unless they are exposed at a very high temperature.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a semiconductor element storage package for accommodating a semiconductor element, and more particularly to a glass-sealed semiconductor element in which the package is sealed by glass welding. This invention relates to improvements to storage packages.

(Prior art and its problems) Conventionally, a glass-sealed semiconductor device storage package for accommodating a semiconductor device, especially a semiconductor integrated circuit device, is made of an electrically insulating material such as alumina ceramics, and the semiconductor device is housed in the center. The insulating base has a rectangular recess for accommodating the semiconductor element, and a low melting point amorphous glass layer for sealing is adhered to the upper surface of the insulating base. A lid body having a concave portion and having a low melting point amorphous glass layer adhered to the bottom surface for sealing, and an external lead terminal for electrically connecting a semiconductor element housed inside to an external electric circuit. The external lead terminal is placed on the top surface of the insulating base, and the external lead terminal is placed on the insulating base by melting the low melting point amorphous glass layer for sealing that has been applied in advance. Next, a semiconductor element is attached to the recessed part of the insulating base, and each electrode of the semiconductor element is connected to an external lead terminal via a bonding wire. After that, the insulating base and the lid are attached to each other. A semiconductor device and Become.

However, in this conventional glass-sealed package for storing semiconductor elements, when attaching the semiconductor element to the recess of the insulating base, the insulating base is approximately
It is heated to a temperature of 50°C, and due to the heating, the low melting point amorphous glass layer for sealing, which temporarily fixes the external lead terminals on the top surface of the insulating base, softens and melts, causing the top surface of the insulating base to melt. The attachment position of the external lead terminal fluctuates, making it difficult to relatively position the external lead terminal and the insulating base.

Further, at this time, a portion of the molten low-melting amorphous glass flows into the recess of the insulating substrate and comes into contact with the semiconductor element, resulting in deterioration of the characteristics of the semiconductor element.

Therefore, in order to eliminate the above-mentioned drawbacks, it has been proposed to use crystalline glass with a high melting point that does not soften or melt even with the heat of mounting and fixing semiconductor elements as the glass for fixing external lead terminals on the insulating substrate. Branch Showa 63-3166
(see issue).

However, this crystalline glass is generally lead oxide (PbO).
) 61.0% by weight, zinc oxide (ZnO) 9.3% by weight, zirconium oxide (ZrO□) 9.2% by weight, silica (Si02) 8.4% by weight, and boron oxide (B20)
*) It consists of 8.8% by weight, and its coefficient of thermal expansion is approximately 80.
The coefficient of thermal expansion at XIO-7/°C is different from that of alumina ceramics (65 to 75 x 10-7/°C) which forms the insulating base and lid of the package for storing semiconductor elements.

Therefore, after a semiconductor element is housed inside this semiconductor element storage package to form a semiconductor device, the semiconductor device is attached and connected to an external circuit board under harsh conditions such as reflow soldering in a high-temperature atmosphere. In this case, the stress generated between the crystalline glass and the insulating substrate due to the difference in their thermal expansion coefficients causes cracks in the crystalline glass, which breaks the hermetic seal of the container and causes damage inside the insulating container. There was a problem to be solved in that it was not possible to operate the semiconductor elements accommodated normally and stably for a long period of time.

(Object of the Invention) The present invention was devised in view of the above-mentioned drawbacks, and its purpose is to eliminate the occurrence of cracks in crystalline glass even under harsh conditions caused by high-temperature atmospheres such as flow soldering. An object of the present invention is to provide a package for storing a semiconductor element, which completely hermetically seals an insulating container housing the semiconductor element and allows the semiconductor element housed inside the insulating container to operate normally and stably for a long period of time. .

(Means for Solving the Problems) The present invention provides an insulating substrate in which an external lead terminal for electrically connecting a semiconductor element to an external circuit is fixed to a crystalline glass that is melt-crystallized, and a temperature lower than that of the crystalline glass. The semiconductor element is hermetically sealed inside by heating and melting the glass member of the lid onto an insulating base and joining the insulating base and the lid. In the glass-sealed semiconductor device storage package, the crystalline glass contains 55.0 to 60.0% by weight of lead oxide, 7.0 to 11.0% by weight of silicon oxide, and 5.5 to 11.0% by weight of boron oxide. 9.5% by weight,
Aluminum oxide 0.2 to 3.0% by weight, zinc oxide 2
It is characterized by comprising 0.0 to 30.0% by weight.

(Example) Next, the present invention will be explained in detail based on the accompanying drawings.

FIG. 1 shows an embodiment of the glass-sealed semiconductor element storage package of the present invention, in which 1 is an insulating base made of an electrically insulating material such as alumina ceramics, and 2 is a lid also made of an electrically insulating material. The insulating base 1 and the lid 2 constitute an insulating container in which the semiconductor element 3 is housed.

The insulating base 1 and the lid 2 each have a recess in the center thereof for accommodating the semiconductor element 3, and the semiconductor element 3 is placed on the bottom surface of the recess 1a of the insulating base 1 with adhesive such as brazing material. It is attached and fixed through.

Note that the insulating base l and the lid body 2 are formed by employing a conventionally well-known press molding method, for example, the insulating base l and the lid body 2 are
When the lid body 2 is made of alumina ceramics, alumina ceramic powder is filled into a press mold having a shape corresponding to the insulating base l or the lid body 2 as shown in FIG. 1, and a constant pressure is applied. It is manufactured by molding and then firing the molded product at a temperature of about 1500°C.

The insulating substrate l has Kovar (Fe-Ni-C) on its upper surface.
One end of an external lead terminal 4 made of a metal material such as O alloy) or 42Alloy (Fe-Ni alloy) is fixed by a glass member 5, and each electrode of the semiconductor element 3 is connected to the external lead terminal 4 through a wire 6. By electrically connecting the external lead terminals 4 to the external circuit, the semiconductor element 3 is connected to the external circuit.

The glass member 5 for fixing the external lead terminal 4 to the upper surface of the insulating base 1 contains 55.0 to 60.0% by weight of lead oxide, 7.0 to 11.0% by weight of silicon oxide, and 5.5 to 9.5% by weight of boron oxide. The glass member 5 is made of crystalline glass containing 0.2 to 30% by weight of aluminum oxide and 20.0 to 3060% by weight of zinc oxide. Approximately 600°C
Therefore, when attaching the semiconductor element 3 to the recess 1a of the insulating base l to which the external lead terminal 4 is fixed via the glass member 5, the semiconductor element 3 will not soften or melt unless it is Even if the insulating substrate 1 is heated to about 450°C to strengthen the adhesive strength, the glass member 5 will soften.
Without melting, the relative positioning of the external lead terminal 4 on the upper surface of the insulating base 1 is perfected, and the glass member 5 melts and comes into contact with the semiconductor element 3, causing deterioration in the characteristics of the semiconductor element 3. Nor.

Further, the glass member 5 has a coefficient of thermal expansion of 62×JO−
7/'C, which approximates the coefficient of thermal expansion of the alumina ceramics forming the insulating substrate l. The glass member 5 never cracks due to the stress generated between the insulating base 1 and the glass member 5 due to the difference in their coefficients of thermal expansion, and the insulating container is always completely hermetically sealed. It becomes possible to operate the semiconductor element housed inside the insulating container normally and stably for a long period of time.

Incidentally, if the lead oxide (PbO) content of the glass member 5 is less than 55.0% by weight, the coefficient of thermal expansion of the glass member 5 will become small and the coefficient of thermal expansion of the glass member 5 will not match that of the insulating substrate l; If it exceeds .0% by weight, the chemical resistance of the glass member 5 will deteriorate and the reliability of hermetic sealing of the insulating container will be greatly reduced, so lead oxide (PbO) should be in the range of 55.0 to 60.0% by weight. Limited.

Furthermore, if silicon oxide (SiO□) is less than 7.0% by weight, the coefficient of thermal expansion becomes too large to match that of the insulating substrate 1, and the fluidity of the glass member 5 is impaired, resulting in the airtight sealing of the insulating container. It became difficult to stop, and it happened again.
If the content exceeds 1.0% by weight, the melting temperature of the glass will rise, causing thermal deterioration of the semiconductor elements housed inside the insulating container.
% by weight.

Further, if boron oxide (B2o3) is less than 5.5% by weight, the coefficient of thermal expansion of the glass member 5 becomes large and the insulating base 1
Boron oxide (B20
a) is limited to a range of 5.5 to 9.5% by weight.

Also, if aluminum oxide (Alz03) is less than 0.2% by weight, the fluidity of the glass will be impaired and it will be difficult to hermetically seal the insulating container, and if it exceeds 3.0% by weight, the heat of the glass member 5 will be reduced. Aluminum oxide (
AlzOs) is limited to a range of 0.2 to 3.0% by weight.

If zinc oxide (ZnO) is less than 20.0% by weight, it will be difficult to crystallize the glass, making it impossible to firmly fix the external lead terminal 4, and if it exceeds 30.0% by weight, the glass will flow. Zinc oxide (ZnO) is
．． It is limited to a range of 0 to 30.0% by weight.

The method for fixing the external lead terminals 4 to the upper surface of the insulating substrate 1 using the glass member 5 is as follows: First, a suitable solvent is added to the above-mentioned glass raw material powder to make a glass paste, and this glass paste is processed using a conventionally well-known method. The top surface of the insulating base 1 is printed and coated using a screen printing method, and then one end of the external lead terminal 4 is placed on the glass paste applied to the insulating base 1 and heated to a temperature of about 500°C. This is done by heating and melting the glass paste to bring it into a crystalline state.

Further, a glass member 7 made of amorphous glass with a low melting point is attached to the lower surface of the lid body 2.
The lid body 2 is attached to the upper surface of the insulating base l, and serves to airtightly seal the inside of the insulating container.

Note that the glass member 7 contains 75% by weight of lead oxide (PbO).
, titanium oxide (TiO+) 9.0% by weight, boron oxide (B20a) 7.5% by weight, zinc oxide (ZnO) 2.
A glass paste obtained by adding an appropriate solvent to the glass raw material powder is applied to the lower surface of the lid body 2 to a desired thickness by employing a conventionally well-known thick film method such as screen printing. It is formed.

Since the glass member 7 has a low softening and melting temperature of about 400°C, the glass member 7 is heated at a temperature of about 40°C.
When heating to a temperature of 0°C and attaching the lid 2 to the top surface of the insulating base 1 to hermetically seal the insulating container, the heat of the hermetic sealing is applied to the glass member 5 attached to the top surface of the insulating base 1. Even if the external lead terminal 4 is applied, the glass member 5 never softens or melts, and the external lead terminal 4 can always be fixed at a predetermined position.

Thus, according to this semiconductor element storage package, the semiconductor element 3 is attached and fixed to the bottom surface of the recess 1a of the insulating base l, and each electrode of the semiconductor element 3 is connected to the external lead terminal 4 by the wire 6, and then the insulation is removed. Base body 1 and lid body 2
The glass member 7 has been previously attached to the lower surface of the lid body 2.
By heating and melting and bonding, the semiconductor element 3 is hermetically sealed inside, thereby completing a semiconductor device as a final product.

(Effects of the Invention) The present invention uses 55.0 to 60.0% by weight of lead oxide, 7.0 to 11.0% by weight of silicon oxide, and 5.0% by weight of boron oxide as a glass member for fixing external lead terminals to the upper surface of an insulating substrate.
5-9.5% by weight, aluminum oxide 0.2-3.
Since the crystalline glass containing 0% by weight and 20.0 to 30.0% by weight of zinc oxide is used, the mounting strength of the semiconductor element is strengthened when the semiconductor element is mounted in the recess of the insulating substrate. Therefore, even if the insulating base is heated to approximately 450°C, the glass member to which the external lead terminals are fixed does not soften or melt at all, and the relative positioning of the external lead terminals on the top surface of the insulating base is perfect. At the same time, the glass member does not melt and come into contact with the semiconductor element, thereby preventing deterioration of the characteristics of the semiconductor element.

Further, the glass member has a coefficient of thermal expansion of 62×10-7
/ ”C, which is similar to the coefficient of thermal expansion of alumina ceramics that forms the insulating substrate, so even if harsh conditions such as flow soldering are applied in a high-temperature atmosphere, there will be no damage between the insulating substrate and the glass member. The glass member never cracks due to the stress caused by the difference in the thermal expansion coefficient of the insulating container, and the hermetic sealing of the insulating container is always perfect, and the semiconductor elements housed inside the insulating container can be operated normally for a long period of time. It becomes possible to operate stably.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of a glass-sealed semiconductor element storage package according to the present invention. 1. Insulating base 2. Lid 4. External lead terminal 5. Glass member 7 made of crystalline glass. Glass member adhered to the lid.

Claims (1)

[Claims] an insulating base on which external lead terminals for electrically connecting a semiconductor element to an external circuit are fixed with crystalline glass melted and crystallized; and a lid body comprising a glass member that softens and melts at a lower temperature than the crystalline glass. A glass-sealed semiconductor element storage device comprising: a glass member of the lid body is heated and melted onto an insulating base body, and a semiconductor element is hermetically sealed inside by bonding the insulating base body and the lid body. In the package, the crystalline glass is lead oxide 55.
0 to 60.0% by weight, silicon oxide 7.0 to 11.
0% by weight, boron oxide 5.5-9.5% by weight, aluminum oxide 0.2-3.0% by weight, zinc oxide 20.0%
A glass-sealed package for housing a semiconductor element, characterized in that the glass-sealed package contains 30.0% by weight.