JPH0883872A - Package for semiconductor element - Google Patents

Abstract

PURPOSE: To obtain a highly reliable package for semiconductor element in which the heat being generated from a semiconductor element contained therein at the time of operation is dissipated well to the outside and the semiconductor element can be operated normally and stably at a low temperature for a long term. CONSTITUTION: In the package for semiconductor element a heat plate 9 is brazed to the surface of an insulating case 4 for containing a semiconductor element 3 wherein a groove G is made in the brazing face of the heat plate 9.

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).

[0002]

2. Description of the Related Art Conventionally, a semiconductor element housing package for housing a semiconductor element is made of an electrically insulating material such as an aluminum oxide sintered body, and is provided on a top surface with a recess for housing the semiconductor element and a periphery thereof. An insulating substrate having a plurality of metallized wiring layers made of refractory metal powder such as tungsten, molybdenum, manganese, etc., which is led out to the periphery, and silver metal or the like for the metallized wiring layers for connecting the semiconductor element to an external electric circuit. It is composed of an external lead terminal attached via a brazing material and a lid, and the semiconductor element is adhered and fixed to the bottom surface of the concave portion of the insulating substrate with an adhesive such as a brazing material, glass or resin. Each electrode of the semiconductor element is electrically connected to the metallized wiring layer via a bonding wire, and thereafter, the semiconductor element is semi-conducted inside the container including the insulating base and the lid. A semiconductor device as a product by sealing the element hermetically.

In the above-mentioned package for accommodating semiconductor elements, a metallized metal layer made of refractory metal powder such as tungsten or molybdenum is deposited on the lower surface of an insulating substrate, and the metallized metal layer is copper or copper-tungsten. A flat plate-shaped radiator made of a metal having good thermal conductivity is attached via a brazing material such as silver solder, and the heat generated when the semiconductor element is operated is absorbed by the radiator via an insulating base. By dissipating the absorbed heat into the atmosphere, the semiconductor element is prevented from being destroyed by heat or being changed in characteristics.

In addition, the heat sink is attached to the insulating base in the package for storing semiconductor elements by sandwiching a brazing material such as silver braze between the heat sink and the metallized metal layer adhered to the insulating base. Then, this is heated to a temperature of about 800 to 900 ° C. to melt the brazing material.

[0005]

However, in this conventional package for accommodating semiconductor elements, the brazing surfaces of the insulating base and the heat radiator are both flat, and the joint area between the insulating base and the heat radiator is wide. When the heat dissipating body is attached to the insulating base by sandwiching the brazing material between the heat dissipating body and the metallized metal layer adhered to the insulating base and heating and melting the brazing material, the brazing material and the insulating base Also, the air existing between the heat sink and the heat radiator is not well discharged to the outside from between the braze material, the insulating substrate and the heat sink, and is trapped in the braze material. It has been formed. Therefore, in the case of accommodating a semiconductor element that has a large amount of heat generation per unit area per unit area, which has recently been highly integrated and highly integrated in this package for accommodating semiconductor elements,
The heat generated during the operation of the semiconductor element is not well conducted and absorbed by the radiator due to the large amount of voids having poor thermal conductivity formed in the brazing material, and as a result, the semiconductor element is generated by the semiconductor element itself. There is a drawback in that the semiconductor element is heated to a high temperature to cause thermal breakdown or thermal change in characteristics.

[0006]

SUMMARY OF THE INVENTION The present invention has been devised in view of the above-mentioned drawbacks, and an object thereof is to satisfactorily dissipate the heat generated during the operation of the semiconductor element housed inside to the outside and keep the semiconductor element at a low temperature. Another object of the present invention is to provide a highly reliable package for accommodating semiconductor elements, which can operate normally and stably for a long period of time.

[0007]

DISCLOSURE OF THE INVENTION The present invention is a package for storing a semiconductor element, which is formed by brazing a flat radiator on the surface of an insulating container for accommodating a semiconductor element, the brazing surface of the radiator. It is characterized in that it is provided with a groove.

Further, the present invention is characterized in that the groove provided in the radiator is sequentially deeper from the central portion of the radiator to the outer peripheral portion thereof.

Furthermore, the present invention is characterized in that the insulating container is made of an aluminum oxide sintered body and the radiator is made of copper-tungsten.

[0010]

According to the package for accommodating a semiconductor element of the present invention, since the groove is provided on the brazing surface of the flat radiator, the solder is interposed between the radiator and the metallized metal layer adhered to the insulating container. When the heat sink is attached to the insulating container by sandwiching the brazing filler metal by heating and melting the brazing filler metal, the air existing between the brazing filler metal, the insulating base and the heat sink is satisfactorily discharged to the outside from the groove provided in the heat sink. As a result, a large amount of voids having poor heat conduction are not formed in the brazing material, and the heat radiator can effectively absorb the heat generated during operation of the semiconductor element. It becomes possible to operate normally and stably at a low temperature for a long period of time.

[0011]

The present invention will now be described in detail with reference to the accompanying drawings. FIG. 1 shows an embodiment of a package for housing a semiconductor device of the present invention, in which 1 is an insulating base and 2 is a lid. An insulating container for housing the semiconductor element 3 with the insulating base 1 and the lid 2.
4 are composed.

The insulating substrate 1 has a semiconductor element on its upper surface.
3 is a substantially rectangular plate-shaped body having a concave portion 1a for accommodating 3, and the semiconductor element 3 is glass on the bottom surface of the concave portion 1a,
It is adhesively fixed through an adhesive such as resin or brazing material.

The insulating substrate 1 is made of an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body,
In the case of an electrically insulating material such as a silicon carbide sintered body or a glass-ceramic sintered body, for example, in the case of an aluminum oxide sintered body, aluminum oxide powder as a main raw material and silicon oxide as a sintering aid. Powder, calcium oxide powder, magnesium oxide powder and the like powdered aluminum oxide sintered body raw material suitable organic binder, solvent, plasticizer and the like is mixed by mixing to form a sludge and the conventionally known doctor blade method and A plurality of ceramic green sheets (unfired ceramic sheets) are obtained by adopting a sheet forming technique such as a calender roll method, and then each of the ceramic green sheets is appropriately punched, and these are vertically stacked in a predetermined order. Laminate to form a ceramic green sheet laminate, and finally laminate the ceramic green sheet It is manufactured by firing at a high temperature (about 1600 ° C.).

Further, a plurality of metallized wiring layers 5 extending from the periphery of the recess 1a to the outer peripheral edge thereof are formed on the insulating substrate 1, and the metallized wiring layer 5 is provided in the periphery of the recess 1a with each of the semiconductor elements 3. The electrodes are electrically connected via bonding wires 6, and external lead terminals 7 connected to an external electric circuit are attached to the outer peripheral portion of the insulating base 1 of the metallized wiring layer 5 via a brazing material such as silver solder. Has been done.

The metallized wiring layer 5 is made of a refractory metal powder such as tungsten, molybdenum, or manganese. The refractory metal powder is mixed with a suitable organic binder, a solvent, or the like, and a metal paste is obtained from the insulating substrate 1. By applying a thick film method such as a conventionally well-known screen printing method to the ceramic green sheet to be applied by printing in advance, it is formed so as to be led out from the periphery of the recess 1a of the insulating base 1 to the outer peripheral edge. .

The metallized wiring layer 5 is formed by depositing a metal such as nickel or gold, which has excellent corrosion resistance and wettability with a brazing material, on the exposed surface by a plating method to a thickness of 1.0 to 20.0 μm. By doing so, it is possible to effectively prevent oxidative corrosion of the metallized wiring layer 5, and to firmly connect the metallized wiring layer 5 and the bonding wire 6 and braze the external lead terminal 7 to the metallized wiring layer 5. You can

Therefore, the metallized wiring layer 5 is usually formed by depositing a metal such as nickel or gold, which has excellent corrosion resistance and wettability with the brazing material, in a thickness of 1.0 to 20.0 μm on the exposed surface.

Further, external lead terminals 7 are attached to the metallized wiring layer 5 via a brazing material such as silver solder, and the external lead terminals 7 are provided in the semiconductor elements 3 housed inside the container 4. By electrically connecting the electrodes to the external electric circuit and connecting the external lead terminal 7 to the external electric circuit, the semiconductor element 3 housed inside the container 4 is connected to the metallized wiring layer 5 and the external lead terminal 7. It will be connected to an external electric circuit via.

The external lead terminal 7 is made of iron-nickel-
It is made of a metal material such as a cobalt alloy or an iron-nickel alloy, and an ingot made of a metal such as an iron-nickel-cobalt alloy is formed into a predetermined plate shape by adopting a conventionally known metal working method such as rolling or punching. It is made by eggplant.

Further, the insulating base body 1 to which the external lead terminals 7 are attached is further covered with a substantially square metallized metal layer 8 on its lower surface, and the metallized metal layer 8 is made of copper, copper-tungsten or the like. A substantially rectangular flat plate-shaped radiator 9 made of a metal having good heat conductivity is brazed via a brazing material 10.

The metallized metal layer 8 acts as a base metal for attaching the heat radiator 9 to the insulating substrate 1, and is formed of a refractory metal powder such as tungsten, molybdenum or manganese, and is usually a meniscus of the brazing material 10. The width of protrusion from the radiator 9 is about 0.1 to 10 mm, and the radius is 0.1 to 10 mm at the corners to relieve the stress when brazing the radiator 9 to the metallized metal layer 8. Designed to have a degree of roundness.

The metallized metal layer 8 is a metal paste obtained by the same method as that for the metallized wiring layer 5, specifically, a metal paste obtained by adding and mixing an appropriate organic binder, a solvent and the like to a refractory metal powder such as tungsten. A thick film method such as the screen printing method is adopted, and the ceramic green sheet to be the insulating substrate 1 is printed and applied in advance to be formed in a substantially rectangular shape on the lower surface of the insulating substrate 1.

The metallized metal layer 8 is formed by depositing a metal such as nickel or gold, which has excellent corrosion resistance and wettability with a brazing material, on the exposed surface by a plating method to a thickness of 1.0 to 20.0 μm. This makes it possible to effectively prevent oxidative corrosion of the metallized metal layer 8 and to firmly braze the heat radiator 9 to the metallized metal layer 8. Therefore, the metallized metal layer 8 is usually formed by depositing a metal such as nickel or gold, which has excellent corrosion resistance and wettability with the brazing material, in a thickness of 1.0 to 20.0 μm on the exposed surface.

The heat dissipating member 9 attached to the metallized metal layer 8 is a substantially rectangular flat plate made of a metal having a good thermal conductivity such as copper-tungsten or oxygen-free copper. Absorbs the heat generated by the device and dissipates it in the atmosphere, and prevents the semiconductor element 3 from being thermally destroyed, causing a change in the characteristics, and malfunctioning.
Usually, a corner with a radius of about 0.1 to 10 mm is provided at the corner portion in order to relieve stress when the heat radiator 9 is brazed to the metallized metal layer 8.

When the radiator 9 is made of, for example, copper-tungsten, tungsten powder (particle size: about 10 μm) 10
It is pressed into a block shape at a pressure of 00 kgf / cm2 and is fired in a reducing atmosphere at a temperature of about 2300 ° C to obtain a porous tungsten sintered body, which is then heated and melted at a temperature of about 1100 ° C. Copper is impregnated into the porous portion of the tungsten sintered body by utilizing the capillarity and is subjected to a conventionally known cutting process to produce a substantially square shape having a predetermined thickness (about 0.3 to 3.0 mm).

The heat dissipating body 9 is effectively oxidized and corroded by depositing a metal having excellent corrosion resistance such as nickel or gold on the exposed surface to a thickness of 1.0 to 20.0 μm by a plating method. Can be prevented. Therefore, the heat dissipating body 9 is usually formed by depositing a metal having excellent corrosion resistance such as nickel or gold in a thickness of 1.0 to 20.0 .mu.m on the exposed outer surface thereof by a plating method.

When the insulating substrate 1 is made of an aluminum oxide sintered body and the radiator 9 is made of copper-tungsten, the thermal expansion coefficients of both are about 6 × 10 ^-6 / ° C.
Since it is close to 7 × 10 ^-6 / ° C., when joining the heat dissipating body 9 to the insulating substrate 1, a large thermal stress is not generated between the two due to the difference in thermal expansion coefficient between the two. Therefore, it is possible to efficiently dissipate the heat generated during the operation of the semiconductor element 3 into the atmosphere through the wide area of the radiator 9 joined to the insulating base 1.

The heat dissipating body 9 is attached to the insulating base body 1 by facing the metallized metal layer 8 adhered to the lower surface of the insulating base body 1 to one main surface of the heat dissipating body 1 and by interposing a silver solder between them. Place the brazing material 10 between them, and after that,
It is performed by heating to a temperature of 800 to 900 ° C. to melt the brazing material 10.

The radiator 9 is further provided with a plurality of grooves G on its brazing surface. Since the heat dissipating body 9 is provided with the groove G on its brazing surface, the brazing material 10 is sandwiched between the heat dissipating body 9 and the metallized metal layer 8 adhered to the insulating substrate 1 to heat the brazing material 10. When the radiator 9 is attached to the insulating substrate 1 by melting, the air existing between the brazing material 10 and the insulating substrate 1 and the radiator 9 is satisfactorily discharged to the outside from the groove G provided in the radiator 9. As a result, the brazing material
Air is not enclosed in the inside of the brazing material 10 and a large amount of voids with poor heat conduction are not formed in the brazing material 10, and the heat dissipating element 9 can effectively absorb the heat generated when the semiconductor element 3 operates. Becomes

The groove G provided in the radiator 9 is formed on the brazing surface of the radiator 9 by subjecting the radiator 9 to metal processing such as cutting and pressing.

As shown in FIG. 2, the groove G formed in the heat dissipating body 9 is formed so as to be gradually deepened from the central portion of the heat dissipating body 9 toward the outer peripheral portion thereof. The brazing material 10 is sandwiched between the deposited metallized metal layer 8 and the heat dissipating body 9, and the brazing material 10 is heated and melted to form the insulating substrate
When the heat radiator 9 is attached, the air existing between the brazing material 10, the insulating substrate 1 and the heat radiator 9 can be efficiently discharged to the outside along the inclination of the groove G. Therefore, the radiator 9
It is preferable that the depth of the through-hole groove G be gradually increased from the central portion of the radiator 9 toward the outer peripheral portion.

Thus, according to the semiconductor element housing package of the present invention, the semiconductor element 3 is formed on the bottom surface of the recess 1a of the insulating base 1.
Are bonded and fixed via an adhesive such as glass, resin or brazing material, and each electrode of the semiconductor element 3 is connected to the metallized wiring layer 5
To the upper surface of the insulating base body 1 via a sealing material such as glass, resin, or brazing material to form the insulating base body 1 and the cover body 2. A semiconductor device as a product is obtained by hermetically housing the semiconductor element 3 inside the container 4.

[0033]

According to the package for accommodating semiconductor elements of the present invention, since the groove is provided on the brazing surface of the flat radiator, the gap between the radiator and the metallized metal layer adhered to the insulating container is provided. When the brazing material is sandwiched between the two, and the brazing material is heated and melted to attach the radiator to the insulating container, the air existing between the brazing material, the insulating base and the radiator is good from the groove provided in the radiator to the outside. As a result, a large amount of voids having poor heat conduction are not formed in the brazing material, and the heat generated by the heat radiator can be effectively absorbed by the heat radiator. It becomes possible to operate normally and stably for a long period of time by always keeping the temperature low.

[Brief description of drawings]

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

FIG. 2 is an enlarged view of an essential part showing an embodiment of the present invention.

[Explanation of symbols]

 1 ... Insulating substrate 3 ... Semiconductor element 4 ... Insulating container 9 ... Heat radiator 10 ... Brazing material G ... Groove

Claims (3)

[Claims] 1. A package for storing a semiconductor element, which is formed by brazing a flat radiator on the surface of an insulating container for accommodating a semiconductor element, wherein a groove is provided on the brazing surface of the radiator. Package for semiconductor device storage. 2. The package for accommodating a semiconductor element according to claim 1, wherein the groove provided in the heat radiator is deeper from the central portion of the heat radiator toward the outer peripheral portion. 3. The package for housing a semiconductor device according to claim 1, wherein the insulating container is made of an aluminum oxide sintered body, and the heat radiator is made of copper-tungsten.