JP2003037202A - Package for accommodating semiconductor element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent thermal destruction of a semiconductor element caused by inefficient dissipation of generated heat to the outside, when the element is actuated. SOLUTION: The package for accommodation of a semiconductor element 4 includes a substrate 1, a frame-shaped insulator 2 having a wiring layer 6 connected with each electrode of the element 4, and a lid member 3 mounted on the insulator 2 to seal the inside of the insulator 2 airtightly. The insulator 2 is a glass ceramic sintered compact having a relative permittivity of not larger than 7 and a thermal expansion coefficient of 4 to 8 ppm/ deg.C. The wiring layer 6 has electrical resistivity of not larger than 2.5 μΩ.cm. The substrate 1 has a three-layered structure of tungsten and copper, that is, a middle layer 1c containing 70-95 wt.% of tungsten and 5-30 wt.% of copper, and upper and lower layers 1b and 1d provided on upper and lower sides of the middle layer and containing 25-65 wt.% of tungsten and 35-75 wt.% of copper.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor element housing package for housing a semiconductor element such as an LSI (Large Scale Integrated Circuit Element) or an optical semiconductor element.

[0002]

2. Description of the Related Art Conventionally, a semiconductor element accommodating package for accommodating a semiconductor element is made of a metal material such as a copper-tungsten alloy or a copper-molybdenum alloy having a mounting portion on which the semiconductor element is mounted. A base body, a frame-shaped insulator made of an electrically insulating material such as an aluminum oxide sintered body attached to the upper surface of the base body so as to surround the mounting portion, and an inner peripheral portion of the frame-shaped insulator A plurality of wiring layers made of refractory metal such as tungsten, molybdenum, manganese, etc., which are adhered and led from the outer periphery to the outer peripheral portion, and a lid which is attached to the upper surface of the frame-shaped insulator and closes the hole inside the insulator. The semiconductor element is bonded and fixed to the semiconductor element mounting portion of the base body with an adhesive, and each electrode of the semiconductor element is formed on the wiring layer formed on the frame-shaped insulator through the bonding wire. Electrically Continued, and thereafter, the glass and the lid to the frame-shaped insulating member so as to close the inner hole of the frame-shaped insulator,
A semiconductor device as a product is obtained by joining them through a sealing material made of resin, a brazing material, etc., and hermetically housing the semiconductor element in a container made of a base, a frame-shaped insulator, and a lid.

In the above-mentioned package for housing a semiconductor element, the base on which the semiconductor element is mounted is made of a metal material such as a copper-tungsten alloy or a copper-molybdenum alloy, and the copper-tungsten alloy or copper-tungsten alloy is used. Since the molybdenum alloy has a high thermal conductivity of about 180 W / m · K and is excellent in thermal conductivity, the base body can well absorb the heat generated during the operation of the semiconductor element and can dissipate it into the atmosphere. As a result, the semiconductor element is always kept at an appropriate temperature, and the semiconductor element is effectively prevented from suffering thermal breakdown or thermal deterioration of its characteristics.

Further, copper-tungsten alloys and copper-based materials used as the base body of the above-mentioned package for accommodating semiconductor elements.
The molybdenum alloy is manufactured by firing tungsten powder or molybdenum powder to obtain a sintered porous body, and then melting the sintered porous body in the pores of the sintered porous body. When impregnated with copper, the sintered porous body has a range of 75 to 90% by weight and copper has a range of 10 to 25% by weight. When the sintered porous body made of molybdenum has been impregnated with copper, the sintered porous body has a range of 80 to 90% by weight. % By weight, and copper is in the range of 10 to 20% by weight.

[0005]

However, in this conventional package for accommodating semiconductor elements, the base body fires tungsten powder or molybdenum powder to obtain a sintered porous body, and the sintered porous body has pores inside. It is formed by impregnating molten copper, and the thermal conductivity of the base increases as the amount of copper increases, but the linear thermal expansion coefficient of the base also increases accordingly. The substrate has a linear thermal expansion coefficient (7.0 ppm / ° C .:
Temperature is different from room temperature to 800 ° C.), the stress generated by the difference in linear thermal expansion coefficient between the two acts on the joint interface between the two, and the stress causes cracks in the joint interface, or in severe cases, the joint interface between the two. If peeling occurs, the reliability of the hermetic sealing of the semiconductor element housing package is impaired, and the problem occurs that the semiconductor elements housed inside cannot be reliably and normally operated. Therefore, it is necessary to approximate the linear thermal expansion coefficient of the base to the linear thermal expansion coefficient of the frame-shaped insulator, and the copper content of the base is 10 to 25% by weight (the base is made of a copper-tungsten alloy). If the content of copper is 10 to 25
In the case of a copper-molybdenum alloy, the content of copper is limited to the range of 10 to 20% by weight, and the thermal conductivity of the substrate is about 180 W / mK at the maximum.
It was about.

Therefore, in the conventional package for accommodating semiconductor elements, the density and the degree of integration have greatly increased in recent years, and when a semiconductor element which generates a large amount of heat during operation is accommodated, the heat generated during operation of the semiconductor element is The semiconductor element cannot be completely diffused to the outside, and as a result, the semiconductor element becomes high temperature due to the heat generated by the element itself, causing thermal damage to the semiconductor element or causing a variation in characteristics to operate stably. It had the drawback of not being able to.

Further, in this conventional package for accommodating semiconductor elements, since the relative permittivity of the aluminum oxide sintered body forming the frame-shaped insulator is as high as 9 to 10 (room temperature, 1 MHz), the frame-shaped insulator is used. The propagation speed of the electric signal transmitted through the provided wiring layer is slow, and therefore, there is a drawback that a semiconductor element that requires high-speed signal propagation cannot be accommodated.

Further, in this conventional package for accommodating semiconductor elements, the wiring layer formed on the frame-shaped insulator is formed of a refractory metal material such as tungsten, molybdenum, manganese, etc. Since the electric resistance is as high as 5.4 μΩ · cm (20 ° C.) or more, when the electric signal is propagated to the wiring layer, the electric signal is greatly attenuated, and the electric signal cannot be accurately and reliably propagated. It also had drawbacks.

The present invention has been devised in view of the above-mentioned drawbacks, and an object thereof is to accommodate therein a semiconductor element which is driven at high speed, and to operate the accommodated semiconductor element normally and stably for a long period of time. Another object of the present invention is to provide a package for accommodating a semiconductor element.

[0010]

SUMMARY OF THE INVENTION According to the present invention, a base having a mounting portion on which a semiconductor element is mounted, and a semiconductor element mounting portion mounted on the base so as to surround the semiconductor element are mounted. A semiconductor element housing comprising a frame-shaped insulator having a wiring layer to which each electrode of the element is connected, and a lid attached to the frame-shaped insulator to hermetically seal the inside of the frame-shaped insulator In the package, the frame-shaped insulator is a glass-ceramic sintered body having a relative dielectric constant of 7 or less and a linear thermal expansion coefficient of 4 ppm / ° C to 8 ppm / ° C, and the wiring layer has an electric resistivity of 2.5 μΩ.
cm or less, the substrate is composed of tungsten and copper, and the intermediate layer of 70 to 95 wt% tungsten and 5 to 30 wt% tungsten has 25 to 65 wt% tungsten and 35 wt% tungsten. It is characterized by having a three-layer structure in which upper and lower layers made up of 75 to 75% by weight are arranged.

Further, according to the present invention, a base having a mounting portion on which a semiconductor element is mounted, and a semiconductor element mounting portion are mounted on the base so as to surround the semiconductor element mounting electrode. A semiconductor element storage package comprising a frame-shaped insulator having a wiring layer to be connected, and a lid body attached to the frame-shaped insulator and hermetically sealing the inside of the frame-shaped insulator, The frame-shaped insulator is a glass ceramics sintered body having a relative dielectric constant of 7 or less and a linear thermal expansion coefficient of 4 ppm / ° C to 8 ppm / ° C, and the wiring layer is made of a metal material having an electrical resistivity of 2.5 μΩ · cm or less. The base is composed of molybdenum and copper, and molybdenum is composed of 30 to 60% by weight and copper is composed of 40 to 70% by weight on the upper and lower surfaces of an intermediate layer composed of 75 to 95% by weight of molybdenum and 5 to 25% by weight of copper. 3 with upper and lower layers
It is characterized by having a layered structure.

According to the package for accommodating semiconductor elements of the present invention, since the frame-shaped insulator is made of a glass ceramic sintered body having a relative dielectric constant of 7 or less, an electric signal transmitted through the wiring layer provided on the frame-shaped insulator. It is possible to accommodate a semiconductor element that requires high-speed signal propagation with a high propagation speed.

According to the package for housing a semiconductor element of the present invention, the frame-shaped insulator is fired at a low temperature (about 800 ° C. to 900 ° C.).
Since it is made of a glass-ceramics sintered body that can be used at a temperature of (.degree. As a result, when an electric signal is propagated to the wiring layer, the electric signal is not attenuated significantly, and the electric signal can be accurately and reliably propagated.

Further, according to the package for accommodating a semiconductor element of the present invention, the base contains 70 to 95% by weight of tungsten,
A three-layer structure in which an upper layer and a lower layer each containing 25 to 65% by weight of tungsten and 35 to 75% by weight of copper are arranged on the upper and lower surfaces of an intermediate layer of 5 to 30% by weight of copper, or 75 to 95% by weight of molybdenum, 30 to 60% by weight of molybdenum on both upper and lower surfaces of the intermediate layer composed of 5 to 25% by weight of copper,
Since the upper and lower layers, which are the semiconductor element mounting portions of the base, have a high thermal conductivity of 250 W / m · K or more, the upper layer of the base has a high thermal conductivity of 250 W / m · K or more. Even if the semiconductor element mounted on the substrate emits a large amount of heat during operation, the heat is quickly spread in the plane direction at the semiconductor element mounting portion of the base body, and the upper layer, the intermediate layer, and the lower layer of the base body are sequentially exposed to the outside. It is possible to efficiently and surely disperse the semiconductor element, whereby the semiconductor element is always kept at an appropriate temperature, and the semiconductor element can be stably and normally operated for a long period of time.

Further, according to the package for accommodating a semiconductor element of the present invention, the base is an intermediate layer consisting of 70 to 95% by weight of tungsten and 5 to 30% by weight of copper, and 25 to 65% by weight of tungsten is formed on both upper and lower surfaces of the intermediate layer. 35 to 75 copper
A three-layer structure in which upper and lower layers of 50% by weight are arranged, and 30 to 60% by weight of molybdenum and 40 to 70% of copper are provided on both upper and lower surfaces of an intermediate layer of 75 to 95% by weight of molybdenum and 5 to 25% by weight of copper. 3 with upper and lower layers consisting of wt%
With a layered structure, by sandwiching an intermediate layer having a small linear thermal expansion coefficient between upper and lower layers having a large linear thermal expansion coefficient, the linear thermal expansion coefficient of the entire substrate can be approximated to the linear thermal expansion coefficient of the frame-shaped insulator, As a result, even when heat is applied to both the base and the frame-shaped insulator when the frame-shaped insulator is attached to the base or when the semiconductor element is operated, there is a gap between the base and the frame-shaped insulator. Large thermal stress due to the difference in linear thermal expansion coefficient between the two does not occur, and thus the airtight sealing of the space for housing the semiconductor element is always perfect, and the semiconductor element can be operated stably and normally. It will be possible.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail with reference to the embodiments shown in the accompanying drawings. FIG. 1 is a cross-sectional view showing an embodiment of a semiconductor element housing package of the present invention. In FIG. 1, 1 is a base, 2 is a frame-shaped insulator, and 3 is a lid. The base 1, the frame-shaped insulator 2 and the lid 3 constitute a container 5 that hermetically houses the semiconductor element 4 therein.

The base 1 has a mounting portion 1a on which the semiconductor element 4 is mounted, and the mounting portion 1 on which the semiconductor element 4 provided on the upper surface of the base 1 is mounted on the outer peripheral portion of the upper surface.
The frame-shaped insulator 2 is attached so as to surround a through an adhesive such as a brazing material, glass, or resin.

The substrate 1 acts as a support member for supporting the semiconductor element 4, and also absorbs heat generated by the semiconductor element 4 during operation and efficiently dissipates the heat into the atmosphere to keep the semiconductor element 4 at an appropriate temperature. The semiconductor element 4 is fixed on the mounting portion 1a of the base 1 surrounded by the frame-shaped insulator 2 with an adhesive such as glass, resin, or brazing material.

The substrate 1 is composed of tungsten and copper, and is manufactured by impregnating molten copper into the pores of a sintered porous body obtained by firing tungsten powder.

Further, on the outer peripheral portion of the upper surface of the base body 1, the base body 1 is provided.
The frame-shaped insulator 2 is attached via an adhesive such as a brazing material, glass, or resin so as to surround the mounting portion 1a on which the semiconductor element 4 mounted on the upper surface of the base 1 is mounted. With the frame-shaped insulator 2, a space for housing the semiconductor element 4 is formed inside.

The frame-shaped insulator 2 attached to the base 1 is made of a glass-ceramics sintered body. Specifically, it is made of 1) a raw material powder obtained by adding alumina or mullite to borosilicate glass. Glass-ceramics sintered body (relative permittivity 5 to 6) 2) Glass-ceramics sintered body (relative permittivity 5 to 6) made from raw material powder made by adding alumina or mullite to cordierite-based crystallized glass 3 ) A glass-ceramic sintered body (having a relative dielectric constant of 5 to 6) made of a raw material powder formed by adding alumina or mullite to mullite-based crystallized glass.

When the frame-shaped insulator 2 is made of, for example, a glass-ceramics sintered body made of a raw material powder obtained by adding alumina or mullite to borosilicate glass, the composition of the raw material powder is 72-70 by weight. 76% silica,
15-17% boron oxide, 2-4% aluminum oxide, 1.5% or less magnesium oxide, 1.1-1.4
% Of zirconium oxide, sodium oxide, potassium oxide and lithium oxide in a total amount of 2.0 to 3.0%, borosilicate glass powder, alumina, quartz and cordierite powder, and a binder containing an acrylic resin as a main component, and A dispersant, a plasticizer, and an organic solvent are added to make a sludge, and the sludge is made into a green sheet (raw sheet) by adopting a doctor blade method or a calendar roll method. Punching is performed and a plurality of these are laminated, and the temperature is about 800 ° C-9
It is manufactured by firing at a temperature of 00 ° C.

A plurality of wiring layers 6 extending from the inner peripheral portion to the upper portion of the frame-shaped insulator 2 are adhered and formed, and one end of the wiring layer 6 exposed at the inner peripheral portion of the frame-shaped insulator 2 is attached. The electrodes of the semiconductor element 4 are electrically connected to each other via the bonding wires 7, and the external lead pins 8 connected to an external electric circuit are connected to an external electric circuit at a portion led out to the upper surface of the frame-shaped insulator 2. It is attached by brazing through the brazing material.

The wiring layer 6 acts as a conductive path when connecting each electrode of the semiconductor element 4 to an external electric circuit, and copper,
It is formed of a metal powder such as silver or gold.

For the wiring layer 6, a metal paste obtained by adding and mixing a suitable organic binder, a solvent, etc. to a metal powder such as copper, silver, gold or the like is previously known to a green sheet as the frame-shaped insulator 2 in advance. By printing and applying a predetermined pattern by using a printing method such as a screen printing method, the frame-shaped insulator 2 is adhered and formed from the inner peripheral portion to the upper surface.

Although the melting point of copper, silver, gold, etc. forming the wiring layer 6 is as low as about 1000 ° C., the firing temperature of the glass-ceramics sintered body constituting the frame-shaped insulator 2 is low, so that the frame-shaped insulator is formed. It is possible to deposit and form a predetermined pattern on 2.

Since the specific electric resistance of copper, silver, gold or the like forming the wiring layer 6 is as low as 2.5 μΩ · cm or less, the semiconductor element 4 housed inside the container via the wiring layer 6 and the external electric Even if an electric signal is taken in and out of the circuit, the electric signal is not greatly attenuated in the wiring layer 6, and as a result, the semiconductor element 4 can be driven accurately and surely.

Further, the wiring layer 6 has a relative dielectric constant of 7 or less (at room temperature, 1 M) of the frame-shaped insulator 2 to which the wiring layer 6 is adhered.
Since the electric signal propagates through the wiring layer 6 at a high speed, the electric signal is transmitted and received between the semiconductor element 4 housed inside the container and the external electric circuit via the wiring layer 6. Even if this is done, the electric signal can be accurately and surely taken in and out of the semiconductor element 4 without causing a delay in the propagation of the electric signal.

When the wiring layer 6 is made of copper or silver, if a metal having excellent corrosion resistance is deposited on the exposed surface to a thickness of 1 μm to 20 μm by a plating method, the wiring layer 6 will be oxidized and corroded. This can be effectively prevented, and the connection between the wiring layer 6 and the bonding wire 7 and the attachment of the external lead pin 8 to the wiring layer 6 can be strengthened.
Therefore, when the wiring layer 6 is made of copper or silver,
To prevent oxidative corrosion of the wiring layer 6 and the bonding wire 7
In order to strengthen the attachment to the external lead pin 8, a metal having excellent corrosion resistance such as gold is used on the exposed surface of the wiring layer 6 in a range of 1 μm to 2 μm.
It is preferable to deposit it to a thickness of 0 μm.

The wiring layer 6 adhered to the frame-shaped insulator 2
The external lead pin 8 brazed to is made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy,
It serves to electrically connect the respective electrodes of the semiconductor element 4 to an external electric circuit.

The external lead pin 8 is formed in a predetermined shape by subjecting an ingot (lump) made of a metal such as an iron-nickel-cobalt alloy to a conventionally known metal working method such as a rolling working method or a punching working method. To be done.

In the package for accommodating semiconductor elements of the present invention, the substrate 1 comprises 25 to 65% by weight of tungsten on the upper and lower surfaces of the intermediate layer 1c comprising 70 to 95% by weight of tungsten and 5 to 30% by weight of copper. It is important to have a three-layer structure in which upper and lower layers 1b and 1d composed of 35 to 75% by weight of copper are arranged.

The substrate 1 is made of tungsten 70 to 95.
% Of tungsten and 5 to 30% by weight of copper, 25 to 65% by weight of tungsten and 35% of copper on the upper and lower surfaces of the intermediate layer 1c.
Since the upper layer 1b, which is the semiconductor element mounting portion 1a of the base 1, has a high thermal conductivity of 250 W / m · K or higher, the upper layer 1b of the base 1 has a high thermal conductivity of 250 W / m · K or more. Even if the semiconductor element 4 mounted on the base 1 generates a large amount of heat during operation, the heat is quickly spread in the plane direction of the semiconductor element mounting portion 1a of the base 1 and the base 1
The upper layer 1b, the intermediate layer 1c, and the lower layer 1d can be sequentially and efficiently diffused to the outside, whereby the semiconductor element 4 is always kept at an appropriate temperature, and the semiconductor element 4 can be stably and normally operated for a long period of time. Is possible.

The substrate 1 is an intermediate layer 1c composed of 70 to 95% by weight of tungsten and 5 to 30% by weight of copper.
It has a three-layer structure in which upper and lower layers 1b and 1d composed of 25 to 65% by weight of tungsten and 35 to 75% by weight of copper are arranged on both upper and lower sides of the intermediate layer 1c having a small linear thermal expansion coefficient. Substrate 1 sandwiched between large upper and lower layers 1b and 1d
Since the coefficient of linear thermal expansion of the whole is approximated to the coefficient of linear thermal expansion of the frame-shaped insulator 2, when the frame-shaped insulator 2 is attached onto the substrate 1 or when the semiconductor element 4 operates, Even if heat acts on both of the frame-shaped insulators 2, a large thermal stress due to the difference in linear thermal expansion coefficient between the base 1 and the frame-shaped insulator 2 does not occur between them. The airtight sealing of the space for housing the semiconductor element 4 is always complete,
It is possible to operate the semiconductor element 4 stably and normally.

The substrate 1 has an intermediate layer 1c in which the amount of tungsten is less than 70% by weight, or 95% by weight.
If it exceeds, the coefficient of linear thermal expansion of the base body 1 greatly differs from the coefficient of linear thermal expansion of the frame-shaped insulator 2, and as a result, the frame-shaped insulator 2 is firmly attached to the base body 1. I can't keep it. Therefore, the amount of tungsten forming the intermediate layer 1c of the substrate 1 is 70-9.
It is specified in the range of 5% by weight.

If the amount of tungsten in the upper and lower layers 1b and 1d is less than 25% by weight, in other words, the amount of copper is 75%.
If it exceeds 5% by weight, the linear thermal expansion coefficient of the substrate 1 is greatly different from the linear thermal expansion coefficient of the frame-shaped insulator 2, so that the frame-shaped insulator 2 can be firmly attached to the substrate 1. When the amount of tungsten exceeds 65% by weight, that is, when the amount of copper is less than 35% by weight, the upper and lower layers 1
When the thermal conductivity of b and 1d cannot be made as high as 250 W / m · K or more and the semiconductor element 4 generates a large amount of heat during operation, the heat is completely transmitted to the outside through the base body 1. Cannot be dissipated, and as a result, the semiconductor device 4
To a high temperature to cause thermal damage to the semiconductor element 4,
The characteristics vary, and it becomes impossible to operate stably. Therefore, the upper and lower layers 1b and 1d of the base 1 are made of 25 to 65% by weight of tungsten and 35 to 75% of copper.
Specified in% by weight.

Further, if the upper and lower layers 1b and 1d are formed to have substantially the same composition and thickness, the stress generated between the upper layer 1b and the intermediate layer 1c and the stress generated between the lower layer 1d and the intermediate layer 1c. The flatness of the substrate 1 is improved by offsetting the stress, and as a result, the frame-shaped insulator 2 can be bonded to the substrate 1 extremely firmly, and the reliability of the hermetic sealing of the container 5 is further ensured. The operation reliability of the semiconductor element 4 housed in the container 5 can be made stable and reliable.

Furthermore, the upper and lower layers 1b and 1d and the intermediate layer 1
c is the thickness of the upper and lower layers 1b and 1d, and X is the thickness of the intermediate layer 1.
When the thickness of c is Y, the heat generated by the semiconductor element 4 via the base 1 can be radiated to the outside better by setting the range of 0.5Y ≦ X ≦ Y. The upper and lower layers 1b,
When the thickness of 1d is X and the thickness of the intermediate layer 1c is Y,
If 0.5Y> X, the upper and lower layers 1b and 1d having a high thermal conductivity of 250 W / m · K or more become thin and there is a risk that the heat generated by the semiconductor element 4 cannot be efficiently dissipated to the outside. When <X, the influence on the entire upper and lower base bodies 1 having a large linear thermal expansion coefficient becomes large, and it becomes difficult to approximate the linear thermal expansion coefficient of the base body 1 to the linear thermal expansion coefficient of the frame-shaped insulator 2. Since there is a risk, the thicknesses of the upper and lower layers 1b and 1d and the intermediate layer 1c are the same as the upper and lower layers 1b and 1d.
When the thickness of d is X and the thickness of the intermediate layer 1c is Y, 0.
The range of 5Y ≦ X ≦ Y is desirable.

The substrate 1 having the three-layer structure is the intermediate layer 1c.
A plate body having a predetermined thickness obtained by impregnating a predetermined amount of tungsten sintered body with a predetermined amount of copper, and a predetermined thickness obtained by impregnating a predetermined amount of tungsten sintered body serving as the upper and lower layers 1b and 1d with a predetermined amount of copper. And the upper and lower plates of the intermediate layer 1c are sandwiched between the upper and lower plates, and then in a vacuum or in a medium at a temperature about 20 ° C. higher than the melting temperature of copper (1083 ° C.). It is manufactured by stacking under pressure in a reducing atmosphere.

Thus, according to the above-mentioned package for housing a semiconductor element, the semiconductor element 4 is adhered and fixed on the semiconductor element mounting portion 1a of the base body 1 via an adhesive such as glass, resin, or brazing material, and the semiconductor element is mounted. Each electrode 4 is connected to a predetermined wiring layer 6 through a bonding wire 7, and then the lid 3 is attached to the upper surface of the frame-shaped insulator 2 with glass, resin,
A semiconductor device as a product is obtained by airtightly housing the semiconductor element 4 inside a container 5 made up of a base body 1, a frame-shaped insulator 2 and a lid body 3 by joining them through a sealing material made of a brazing material or the like. .

Next, another embodiment of the present invention will be described.

In the above-mentioned package for accommodating semiconductor elements, the base 1 is 25 to 65% by weight of tungsten and 35 to 65% by weight of tungsten on the upper and lower surfaces of the intermediate layer 1c composed of 70 to 95% by weight of tungsten and 5 to 30% by weight of copper. The upper and lower layers 1b and 1d made up of 75% by weight are arranged in a three-layer structure, and this is composed of 75 to 95% by weight of molybdenum and 5 to 25% by weight of copper.
It is also possible to have a three-layer structure in which the upper and lower layers 1b and 1d composed of 60 to 60% by weight and 40 to 70% by weight of copper are arranged. The substrate 1 contains 75 to 95% by weight of molybdenum and 5 to 25 of copper.
3% molybdenum is formed on both upper and lower surfaces of the intermediate layer 1c, which is made up by weight.
When the upper and lower layers 1b and 1d composed of 0 to 60% by weight and 40 to 70% by weight of copper are arranged in a three-layer structure, the thermal conductivity of the upper layer 1b which is the semiconductor element mounting portion 1a of the substrate 1 is 25%.
Even if the semiconductor element 4 mounted on the base 1 emits a large amount of heat during operation, the heat is swift in the plane direction in the semiconductor element mounting portion 1a of the base 1. The upper layer 1b of the substrate 1, the intermediate layer 1c,
The lower layer 1d can be sequentially and efficiently dissipated to the outside, whereby the semiconductor element 4 is always kept at an appropriate temperature, and the semiconductor element 4 can be stably and normally operated for a long period of time.

Further, molybdenum is 30 to 60% by weight and copper is 40 to 7 on both upper and lower surfaces of the intermediate layer 1c composed of 75 to 95% by weight of molybdenum and 5 to 25% by weight of copper.
The base body 1 having a three-layer structure in which the upper and lower layers 1b and 1d of 0 wt% are arranged has the intermediate layer 1c having a small linear thermal expansion coefficient sandwiched between the upper and lower layers 1b and 1d having a large linear thermal expansion coefficient, and the linear thermal expansion of the entire base body 1 is performed. Since the coefficient is approximated to the linear thermal expansion coefficient of the frame-shaped insulator 2, when the frame-shaped insulator 2 is attached onto the substrate 1 or when the semiconductor element 4 is operated, the base 1 and the frame-shaped insulator 2 are separated. Even if heat is applied to both, a large thermal stress due to the difference in linear thermal expansion coefficient between the base 1 and the frame-shaped insulator 2 does not occur, and the semiconductor element 4 is housed thereby. The airtight sealing of the void is always complete, and the semiconductor element 4 can be stably and normally operated.

When the amount of molybdenum in the intermediate layer 1c of the substrate 1 is less than 75% by weight or exceeds 95% by weight, the coefficient of linear thermal expansion of the substrate 1 is linear thermal expansion of the frame-shaped insulator 2. This greatly differs from the coefficient, and as a result, the frame-shaped insulator 2 cannot be firmly attached to the base body 1. Therefore, the amount of molybdenum forming the intermediate layer 1c of the substrate 1 is specified in the range of 75 to 95% by weight.

When the amount of molybdenum in the upper and lower layers 1b and 1d is less than 30% by weight, in other words, when the amount of copper exceeds 70% by weight, the coefficient of linear thermal expansion of the substrate 1 is the frame-shaped insulator 2.
The coefficient of linear thermal expansion is significantly different from that of the frame-shaped insulator 2 and it becomes impossible to firmly attach the frame-shaped insulator 2 to the substrate 1. If the amount of molybdenum exceeds 60% by weight,
In other words, when the copper content is less than 40% by weight, the upper and lower layers 1b,
When the thermal conductivity of 1d cannot be made as high as 250 W / m · K or more and the semiconductor element 4 generates a large amount of heat during operation, the heat is completely dissipated to the outside through the base body 1. As a result, the semiconductor element 4 is heated to a high temperature, causing thermal damage to the semiconductor element 4 or variation in characteristics, which makes it impossible to operate the semiconductor element 4 stably. Therefore, the upper and lower layers 1b and 1d of the substrate 1 contain molybdenum of 30 to 60% by weight and copper of 40 to 70% by weight.
Specified in.

Further, if the upper and lower layers 1b and 1d are formed to have substantially the same composition and thickness, the stress generated between the upper layer 1b and the intermediate layer 1c and the stress generated between the lower layer 1d and the intermediate layer 1c. The stress is canceled out, and the flatness of the substrate 1 is improved,
As a result, the frame-shaped insulator 2 can be bonded to the base body 1 extremely firmly, and the reliability of the hermetic sealing of the container 5 is further ensured, and the operation reliability of the semiconductor element 4 housed inside the container 5 is improved. Can be stable and reliable.

Furthermore, the upper and lower layers 1b and 1d and the intermediate layer 1
c is the thickness of the upper and lower layers 1b and 1d, and X is the thickness of the intermediate layer 1.
When the thickness of c is Y, the heat generated by the semiconductor element 4 via the base 1 can be radiated to the outside better by setting the range of 0.5Y ≦ X ≦ Y. The upper and lower layers 1b,
When the thickness of 1d is X and the thickness of the intermediate layer 1c is Y,
If 0.5Y> X, the upper and lower layers 1b and 1d having a high thermal conductivity of 250 W / m · K or more become thin and there is a risk that the heat generated by the semiconductor element 4 cannot be efficiently dissipated to the outside. When <X, the influence on the entire upper and lower base bodies 1 having a large linear thermal expansion coefficient becomes large, and it becomes difficult to approximate the linear thermal expansion coefficient of the base body 1 to the linear thermal expansion coefficient of the frame-shaped insulator 2. Since there is a risk, the thicknesses of the upper and lower layers 1b and 1d and the intermediate layer 1c are the same as the upper and lower layers 1b and 1d.
When the thickness of d is X and the thickness of the intermediate layer 1c is Y, 0.
The range of 5Y ≦ X ≦ Y is desirable.

The substrate 1 having the three-layer structure is the intermediate layer 1c.
A plate body having a predetermined thickness obtained by impregnating a predetermined amount of molybdenum sintered body with a predetermined amount of copper and a predetermined thickness obtained by impregnating a predetermined amount of molybdenum sintered body serving as the upper and lower layers 1b and 1d with a predetermined amount of copper. And the upper and lower plates of the intermediate layer are sandwiched by the plate layers of the upper and lower layers, and then the melting temperature of copper (1083
In vacuum or at a temperature about 20 ° C higher than
It is manufactured by stacking under pressure in a reducing atmosphere.

The present invention is not limited to the above-mentioned embodiments, but various modifications can be made without departing from the gist of the present invention.

[0050]

According to the package for accommodating a semiconductor element of the present invention, the frame-shaped insulator is formed of a glass ceramic sintered body having a relative dielectric constant of 7 or less, so that the wiring layer provided on the frame-shaped insulator is transmitted. It is possible to accommodate a semiconductor element that requires high-speed signal propagation by increasing the electrical signal propagation speed.

According to the package for housing a semiconductor element of the present invention, the frame-shaped insulator is fired at a low temperature (about 800 ° C. to 900 ° C.).
Since it is made of a glass-ceramics sintered body that can be used at a temperature of (.degree. As a result, when an electric signal is propagated to the wiring layer, the electric signal is not attenuated significantly, and the electric signal can be accurately and reliably propagated.

Further, according to the package for accommodating semiconductor elements of the present invention, the base contains 70 to 95% by weight of tungsten,
A three-layer structure in which an upper layer and a lower layer each containing 25 to 65% by weight of tungsten and 35 to 75% by weight of copper are arranged on the upper and lower surfaces of an intermediate layer of 5 to 30% by weight of copper, or 75 to 95% by weight of molybdenum, 30 to 60% by weight of molybdenum on both upper and lower surfaces of the intermediate layer composed of 5 to 25% by weight of copper,
Since the upper and lower layers, which are the semiconductor element mounting portions of the base, have a high thermal conductivity of 250 W / m · K or more, the upper layer of the base has a high thermal conductivity of 250 W / m · K or more. Even if the semiconductor element mounted on the substrate emits a large amount of heat during operation, the heat is quickly spread in the plane direction at the semiconductor element mounting portion of the base body, and the upper layer, the intermediate layer, and the lower layer of the base body are sequentially exposed to the outside. It is possible to efficiently and surely disperse the semiconductor element, whereby the semiconductor element is always kept at an appropriate temperature, and the semiconductor element can be stably and normally operated for a long period of time.

Further, according to the package for accommodating a semiconductor element of the present invention, the base is an intermediate layer consisting of 70 to 95% by weight of tungsten and 5 to 30% by weight of copper, and 25 to 65% by weight of tungsten on the upper and lower surfaces of the intermediate layer. 35 to 75 copper
A three-layer structure in which upper and lower layers of 50% by weight are arranged, and 30 to 60% by weight of molybdenum and 40 to 70% of copper are provided on both upper and lower surfaces of an intermediate layer of 75 to 95% by weight of molybdenum and 5 to 25% by weight of copper. 3 with upper and lower layers consisting of wt%
3. It has a layered structure, and an intermediate layer having a small coefficient of linear thermal expansion is sandwiched by upper and lower layers having a large coefficient of linear thermal expansion to approximate the coefficient of linear thermal expansion of the entire substrate to the coefficient of linear thermal expansion of the frame-shaped insulator.
0 ppm / ° C to 8.0 ppm / ° C (room temperature to 800 ° C)
As a result, even when heat is applied to both the base and the frame-shaped insulator when the frame-shaped insulator is attached to the base or when the semiconductor element is operated, the base and the frame-shaped insulator are There is no large thermal stress due to the difference in the linear thermal expansion coefficient between the two, and this ensures that the air-tight seal of the space that houses the semiconductor element is always perfect, and the semiconductor element is stable and normal. Can be activated.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a semiconductor element housing package of the present invention.

[Explanation of symbols]

1 ... Base 1a ... ・ Mounting part 1b ... upper layer 1c ... Middle layer 1d ... Lower layer 2 ... Frame-shaped insulator 3 ... Lid 4 ... Semiconductor element 5 ... Container 6 ... Wiring layer 7 ... Bonding wire 8: External lead pin

Claims (2)

[Claims] 1. A base having a mounting portion on which a semiconductor element is mounted, and a semiconductor element mounting portion mounted on the base so as to surround the semiconductor element, and each electrode of the semiconductor element is connected. A package for accommodating a semiconductor element, comprising: a frame-shaped insulator having a wiring layer; and a lid attached to the frame-shaped insulator to hermetically seal the inside of the frame-shaped insulator. The insulator has a relative permittivity of 7 or less and a linear thermal expansion coefficient of 4 ppm / ° C.
It is a glass-ceramics sintered body of 8 ppm / ° C., the wiring layer is a metal material having an electric resistivity of 2.5 μΩ · cm or less, and the base is made of tungsten and copper. Tungsten is 70 to 95% by weight and copper is 5 to 5 wt%. 25 to 65% by weight of tungsten and 3% of copper on the upper and lower surfaces of the intermediate layer consisting of 30% by weight.
A package for accommodating a semiconductor element, which has a three-layer structure in which upper and lower layers of 5 to 75% by weight are arranged. 2. A base having a mounting portion on which a semiconductor element is mounted, and a semiconductor element mounting portion mounted on the base so as to surround the base, and each electrode of the semiconductor element is connected. A package for accommodating a semiconductor element, comprising: a frame-shaped insulator having a wiring layer; and a lid attached to the frame-shaped insulator to hermetically seal the inside of the frame-shaped insulator. The insulator has a relative permittivity of 7 or less and a linear thermal expansion coefficient of 4 ppm / ° C.
It is a glass-ceramics sintered body of 8 ppm / ° C., the wiring layer is a metal material having an electric resistivity of 2.5 μΩ · cm or less, and the substrate is made of molybdenum and copper.
It has a three-layer structure in which upper and lower layers of molybdenum of 30 to 60% by weight and copper of 40 to 70% by weight are disposed on both upper and lower surfaces of an intermediate layer of 5% by weight and 5 to 25% by weight of copper. A package for semiconductor device storage characterized by.