JP2514911Y2 - Package for storing semiconductor devices - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an improvement of a semiconductor element housing package for housing a semiconductor element.

(Prior Art) Conventionally, a semiconductor element, particularly a semiconductor integrated circuit element (LSI)
The semiconductor element housing package for housing etc. is generally made of an electrically insulating material such as alumina ceramics,
An insulating substrate having a recess for mounting and accommodating a semiconductor element in the center of its upper surface and a metallized wiring layer made of a high melting point metal powder such as tungsten, molybdenum, or manganese led out from the periphery of the recess to the outer peripheral edge; External lead terminals, which are attached to the metallized wiring layer via a brazing material to electrically connect the semiconductor element to an external electric circuit, and a lid body. While fixing, each electrode of the semiconductor element is connected to the metallized wiring layer via a bonding wire,
After that, a lid is bonded to the upper surface of the insulating base through a sealing member made of glass, resin, or the like, and the semiconductor element is hermetically sealed inside the container made of the insulating base and the lid, thereby obtaining a final product. It becomes a semiconductor device.

However, in recent years, semiconductor devices have been rapidly increased in density, integration, and driving speed, and when the semiconductor device is housed in the conventional semiconductor device housing package, it has the following drawbacks. Become.

That is, (1) thermal expansion coefficient of the alumina ceramic constituting the silicon and package insulating substrate of the semiconductor device are each ^{3.0~3.5 × 10 -6 /℃,6.0~7.5×10 -6 / ℃} , large Due to the difference, when heat generated when the semiconductor element is operated is applied to both, a large thermal stress is generated between the two, and the semiconductor element is damaged by the thermal stress or peeled from the insulating substrate. The function as a semiconductor device is lost.

(2) Since the alumina ceramics that constitutes the insulating base of the package has a high dielectric constant of 9 to 10 (room temperature 1MHz), the propagation speed of the electric signal transmitted through the metallized wiring layer provided on the insulating base is slow, and therefore the high speed of the electric signal. A semiconductor element that requires propagation cannot be accommodated.

(3) The thermal conductivity of the alumina ceramics that constitutes the insulating base of the package is as low as about 17 W / m · K, so the heat generated during the operation of the semiconductor element cannot be dissipated into the atmosphere satisfactorily. The semiconductor element is heated to a high temperature by the heat generated by the element itself, causing a malfunction.

It had a defect such as.

Therefore, in order to eliminate the above-mentioned drawbacks, the portion where the semiconductor element is mounted and fixed has a thermal conductivity of 100 W / m / K or more and a thermal expansion coefficient of 4.6 × 10 ⁻⁶ / ° C. close to that of the semiconductor element. With a structure in which aluminum-based sintered material is used, and the metallized wiring layer part is made of mullite-based sintered material with a low dielectric constant of 6.4 (room temperature 1 MHz), and each is attached via a brazing material such as silver solder. A package for housing a semiconductor device has been proposed.

However, when the aluminum nitride sintered body and the mullite sintered body are attached via the silver brazing material, the silver brazing material has a high Vickers hardness (Hv) of Hv ≧ 83 and the aluminum nitride sintering body when the mullite sintered material is brazing both from like to have a slight difference in that the thermal expansion coefficient of each of which approximates a 4.6 × 10 ^-6 /℃,4.2×10 ^-6 / ℃ When the brazing area is as wide as 4.0 mm ² or more, a large thermal stress is generated between the two, and the bonding strength between the aluminum nitride sintered body and the mullite sintered body is reduced by the thermal stress, or This causes a defect that the mullite sintered body having low mechanical strength is damaged.

(Purpose of the Invention) The present invention has been devised in view of the above-mentioned drawbacks, and the purpose thereof is to firmly attach the aluminum nitride sintered body and the mullite sintered body, and to achieve high density and high integration inside. Another object of the present invention is to provide a semiconductor element housing package capable of hermetically housing a semiconductor element that has been driven at high speed and driven at high speed.

(Means for Solving the Problems) The present invention is made of an aluminum nitride sintered body, and an insulating substrate having a mounting portion on which a semiconductor element is mounted is surrounded by an insulating substrate. In a package for storing a semiconductor element, in which a frame made of a quality sintered body is attached via a brazing material, the Vickers hardness (H
v) is Hv ≦ 70.

(Example) Next, this invention is demonstrated in detail based on an accompanying drawing.

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 frame.

The insulating base 1 is provided with a convex mounting portion 1a on which the semiconductor element 3 is mounted, in the center of the upper surface thereof.
The semiconductor element 3 is attached to the upper side with an adhesive.

The insulating substrate 1 is made of an aluminum nitride sintered body, and the aluminum nitride sintered body has a thermal conductivity of 100 W.
When the semiconductor element 3 is mounted and fixed on the insulating substrate 1, the insulating substrate 1 absorbs the heat generated by the semiconductor element 3 and absorbs the heat, because the material is as high as / m · K or more and easily conducts heat. The heat can be well diffused into the atmosphere, and as a result, the semiconductor element 3 is always kept at a low temperature,
Can be operated normally and stably for a long period of time.

Further, since the aluminum nitride sintered body constituting the insulating substrate 1 has a thermal expansion coefficient of 4.6 × 10 ⁻⁶ / ° C., which is close to the thermal expansion coefficient of the semiconductor element 3 and has a small joint area between them. After mounting and fixing the semiconductor element 3 on the mounting portion 1a of the insulating substrate 1, even if heat generated when the semiconductor element 3 is operated is applied to both, a large thermal stress is generated between them. The semiconductor element 3 is not damaged or peeled off from the insulating substrate 1 due to the thermal stress.

The insulating substrate 1 made of the aluminum nitride sintered body is prepared by adding aluminum nitride powder as a main material, powders of yttrium oxide, calcia, etc. as a sintering aid, and an appropriate organic solvent, and a solvent. A green sheet (raw sheet) is formed by making a sludge and adopting a doctor blade method to the sludge, and thereafter, the green sheet is subjected to an appropriate punching process and a plurality of these are laminated to each other, and about 1800 It is manufactured by firing at a high temperature of ℃.

Further, the outer peripheral edge of the upper surface of the insulating base 1 is surrounded by a convex mounting portion 1a provided on the upper surface of the insulating base 1 so as to surround the frame 2
Are brazed and attached, and a space for accommodating the semiconductor element 3 is formed inside by the insulating base 1 and the frame 2.

The insulating base 1 and the frame 2 are attached to each other by depositing a metallized metal layer 7 on the lower surface of the frame 2 in advance and then depositing the metallized metal layer 7 on the upper surface of the insulating substrate 1 in advance. The brazing material 9 is attached to the metallized metal layer 8 which has been formed.

The metallized metal layers 7 and 8 deposited on the insulating substrate 1 and the frame 2 are made of refractory metal powder such as tungsten, molybdenum, and manganese. An organic solvent and a solvent are added to and mixed with the refractory metal powder. The metal paste thus obtained is applied by printing to the upper surface of the insulating substrate 1 and the lower surface of the frame body 2 by a conventionally known screen printing method, and then baked at a high temperature to adhere to each of the insulating substrate 1 and the frame body 2. To be done.

The brazing material 9 for attaching the insulating base 1 and the frame 2 is made of, for example, gold, silver, or a metal containing gold or silver as a main component, and its Vickers hardness (Hv) is Hv ≦ 70. .

Since the brazing material 9 has a Vickers hardness (Hv) of Hv ≦ 70 and is soft, the brazing area is 4.0 mm ² or more when the insulating base body 1 and the frame body 2 are brazed and attached. Therefore, even if a large thermal stress is generated between the insulating base 1 and the frame body 2, the thermal stress is absorbed by deforming the brazing material 9, whereby the attachment strength between the insulating base body 1 and the frame body 2 is increased. Does not decrease and the frame 2 is not damaged.

The brazing material 9 has a Vickers hardness (Hv) of Hv>
When it becomes 70, the brazing material 9 becomes too hard, and the brazing material 9 cannot completely absorb the thermal stress generated between the insulating base 1 and the frame 2, so that the insulating base 1 and the frame 2 are separated from each other. The wearing strength may be reduced, or the frame body 2 may be damaged. Therefore, the Vickers hardness (Hv) of the brazing material 9 for attaching the insulating base body 1 and the frame body 2 is specified as Hv ≦ 70.

The frame 2 attached to the insulating substrate 1 is made of a mullite sintered body. For example, mullite, silica, magnesia, calcia, and other raw material powders are mixed with an appropriate organic solvent and a solvent to form a slurry. A green sheet (green sheet) is formed by adopting this together with the doctor blade method, and then the green sheet is subjected to appropriate punching processing and a plurality of layers are laminated, and about 1400 to 18
It is manufactured by firing at a temperature of 00 ° C.

The frame body 2 has a metallized wiring layer 4 made of a high melting point metal powder such as molybdenum or tungsten embedded therein, and the metallized wiring layer 4 serves to connect the electrode of the semiconductor element 3 to the external lead pin 5. The external lead pin 5 is attached to one end thereof, and the bonding wire 6 connected to the electrode of the semiconductor element 3 is attached to the other end thereof.

Since the frame body 2 has a low induction rate of 6.3 (room temperature 1 MHz) of the mullite sintered body constituting the frame body 2, the propagation speed of the electric signal transmitted through the metallized wiring layer 4 embedded in the frame body 2 is extremely high. As a result, it becomes possible to accommodate a semiconductor element which is driven at high speed and has a high electric signal propagation speed in the package.

In addition, the external lead pin 5 attached to the metallized wiring layer 4 embedded in the frame 2 has the semiconductor element 3 housed therein.
The electrodes are used to electrically connect each electrode to an external electric circuit, and a metal such as Kovar metal or 42Alloy is formed into a pin shape.

It should be noted that when a metal having good conductivity and excellent corrosion resistance made of nickel, gold, or the like is layered on the outer surface of the external lead pin 5 to a thickness of 2.0 to 10.0 μm by a conventionally known plating method, The electrical connection between the lead pin 5 and the external electric circuit is improved, and the oxidative corrosion of the external lead pin 5 is effectively prevented. Therefore, it is preferable to deposit a metal, such as nickel or gold, having good conductivity and excellent corrosion resistance on the outer surface of the external lead pin 5 in a thickness of 2.0 to 10.0 μm.

Thus, according to the semiconductor element housing package of the present invention, the semiconductor element 3 is fixedly mounted on the convex mounting portion 1a of the insulating substrate 1 to which the frame body 2 is mounted, and each electrode of the semiconductor element 3 is bonded. The semiconductor device as a final product is obtained by connecting to the metallized wiring layer 4 via the wire 6 and attaching the lid 10 to the upper surface of the frame 2 via a sealing member.

(Effect of the Invention) According to the package for housing a semiconductor device of the present invention, the thermal conductivity of the insulating substrate on which the semiconductor device is mounted and fixed is 100 w / mK.
The heat generated by the semiconductor element housed inside, which is formed of the aluminum nitride sintered body described above, is satisfactorily dissipated to the atmosphere through the insulating substrate, and as a result, the semiconductor element is always kept at a low temperature and It can operate normally and stably for a long period of time.

Since the insulating substrate on which the semiconductor element is mounted and fixed is made of an aluminum nitride sintered body having a thermal expansion coefficient close to that of the semiconductor element, after mounting and fixing the semiconductor element on the insulating substrate, Even if heat generated when the semiconductor element is actuated is applied to both the insulating substrate and the semiconductor element, a large thermal stress does not occur between the two, and the semiconductor element may be damaged by the thermal stress. It does not peel off from the insulating substrate.

Furthermore, the metallized wiring layer that connects each electrode of the semiconductor element housed inside to the external electric circuit has a dielectric constant of 6.3 (room temperature 1 MH
z) and a frame body made of a low mullite sintered body, the propagation speed of the electric signal transmitted through the metallized wiring layer 4 can be made extremely fast. As a result, the propagation speed of the electric signal inside the package can be increased. It is also possible to accommodate a semiconductor element that drives at high speed and at high speed.

Furthermore, since the insulating base body made of the aluminum nitride sintered body and the frame body made of the mullite sintered body were attached by using the brazing material having the Vickers hardness (Hv) of Hv ≦ 70, the insulating base body and the frame body were attached. When brazing and attaching and, the brazing area
4.0 mm ² or more wide basis becomes, heat stress as a large thermal stress is generated between the insulating substrate and the frame is absorbed by deforming the brazing material, whereby preparative between the insulating substrate and the frame The adhesion strength does not decrease, and the frame having weak mechanical strength is not damaged.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a package for housing a semiconductor device of the present invention. DESCRIPTION OF SYMBOLS 1 ... Insulating base body, 1a ... Convex mounting part 2 ... Frame body, 9 ... Brazing material

Claims (1)

(57) [Scope of utility model registration request] 1. An insulating substrate made of an aluminum nitride sintered body, having an upper surface on which a semiconductor element is mounted,
In a package for storing a semiconductor device, in which a frame made of a mullite sintered body is attached via a brazing material so as to surround the mounting portion, the Vickers hardness (Hv) of the brazing material is Hv ≦ 70. A package for housing a semiconductor element, which is characterized in that