JPH06132415A - Package for semiconductor-element housing - Google Patents

Abstract

PURPOSE:To completely airtightly seal a semiconductor element, to make the propagation loss of a signal extremely small and to operate the semiconductor element normally and stably for a long time by a method wherein an insulating frame body is attached and bonded horizontally and firmly to a heat-conductive base body provided with a protrusion part on the top surface. CONSTITUTION:A package for semiconductor-element housing use is formed by attaching and bonding an insulating frame body 2 to a heat-conductive base body 1 provided with a protrusion 1a, on which a semiconductor element 4 is mounted, on the surface, in such a way that the insulating frame body surrounds the protrusion part 1a. In the package, a cutout part is formed at the inner circumferential corner part on the rear surface of the insulating frame body 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a semiconductor element housing package for housing a semiconductor element.

[0002]

2. Description of the Related Art In recent years, as the performance and speed of information processing devices have increased, the density and integration of the semiconductor elements constituting the information processing devices have rapidly increased. Therefore, the amount of heat generated per unit area and unit volume of the semiconductor element increases during operation, and how to efficiently remove the heat is a problem in order to operate the semiconductor element normally and stably. .

Conventionally, as a method of removing heat generated by a semiconductor element, copper, copper-tungsten alloy, nitride having a protrusion 21a for mounting the semiconductor element 20 on the center of the upper surface as shown in FIGS. 3 and 4 has been used. A semiconductor element storage package having a structure in which an insulating frame body 22 is brazed and attached so as to surround the protrusion 21a on a base body 21 made of a heat conductive material such as an aluminum sintered body is prepared. This is performed by mounting the semiconductor element 20 on the upper surface of the protruding portion 21a of 21 and causing the base 21 to absorb the heat generated from the semiconductor element 20 and radiating the absorbed heat into the atmosphere.

The substrate 21 having the projections 21a is a flat substrate 21 made of, for example, copper, copper-tungsten alloy or the like.
It is manufactured by grinding the upper surface of and forming a protrusion 21a at the center.

The insulating frame 22 has a metallized wiring layer made of tungsten, molybdenum, manganese or the like on the upper surface.
23 is formed, and each electrode of the semiconductor element 20 housed inside can be electrically connected to an external electric circuit via the metallized wiring layer 23.

Further, a metallized metal layer 24 made of tungsten, molybdenum, manganese or the like is formed on the lower surface of the insulating frame 22, and the metallized metal layer 24 is used as a substrate.
The insulating frame body 22 is attached to the base 21 by brazing it to the 21 via a brazing material 25 such as silver brazing.

[0007]

However, in this conventional package for accommodating semiconductor elements, the protrusions 21a provided on the base 21 made of a thermally conductive material are formed by grinding the base 21. Cage, protrusion 21a
An arcuate bulge A is formed between the base of the base and the upper surface of the base 21.

Therefore, when the insulating frame body 22 is brazed and attached on the base body 21 having the protruding portion 21a so as to surround the protruding portion 21a, the inner peripheral corner portion of the lower surface of the insulating frame body 22 is the base body. Insulation frame body
22 A gap between the lower surface and the upper surface of the base 21 occurs,
As a result, there are drawbacks that brazing and attachment of the base body 21 and the insulating frame body 22 becomes incomplete and the reliability of hermetic sealing of the semiconductor element housing package becomes extremely low.

When the insulating frame 22 is obliquely attached to the base 21 due to the bulging portion A, the electrodes of the semiconductor element 20 are bonded to the metallized wiring layer 23 of the insulating frame 22 by bonding wires.
Bonding wire 26 when electrically connected through 26
When the semiconductor element is driven in a high frequency band, there is a drawback that a large loss occurs in signal propagation due to a mismatch in characteristic impedance due to a difference in length of the bonding wire 26. Had.

[0010]

SUMMARY OF THE INVENTION The present invention has been devised in view of the above-mentioned drawbacks, and an object of the invention is to fix a semiconductor device by horizontally and firmly attaching an insulating frame to a heat conductive substrate having a projection on its upper surface. It is an object of the present invention to provide a package for housing a semiconductor element, which is capable of operating the semiconductor element normally and stably for a long period of time while achieving hermetic sealing and minimizing signal transmission loss.

[0011]

SUMMARY OF THE INVENTION The present invention is a semiconductor in which an insulating frame is attached to a heat conductive substrate having a projection on which a semiconductor element is mounted, so as to surround the projection. A package for storing an element, characterized in that a notch is formed at an inner peripheral corner of a lower surface of the insulating frame.

[0012]

The present invention will now be described in detail with reference to the accompanying drawings. 1 and 2 show an embodiment of a semiconductor element housing package of the present invention, in which 1 is a base, 2 is an insulating frame, and 3 is a lid.

The base 1 has a semiconductor element on the center of its upper surface.
4 is provided with a convex projection 1a on which the projection 4a is placed.
The semiconductor element 4 is attached onto the 1a via an adhesive.

The base 1 is made of a metal having good thermal conductivity such as copper or a copper-tungsten alloy. The copper, the copper-tungsten alloy, etc. have a high thermal conductivity of 200 W / m · K or more, and heat When the semiconductor element 4 is placed on the protruding portion 1a of the base 1 because it is easily conducted, the base 1 can absorb the heat generated by the semiconductor element 4 and can satisfactorily release the absorbed heat to the atmosphere. As a result, the semiconductor element 4 can always be kept at a low temperature, and the semiconductor element 4 can be normally and stably operated for a long period of time.

When the substrate 1 is made of, for example, a copper-tungsten alloy, tungsten powder (particle size: about 10
(μm) at a pressure of 1000 Kg / cm ^{2 and} is pressed at a temperature of about 2300 ° C. in a reducing atmosphere to obtain a porous tungsten sintered body, which is then heated and melted at a temperature of 1100 ° C. Copper is impregnated into the porous portion of the tungsten sintered body by utilizing the capillarity.

The protrusion 1a provided in the central portion of the upper surface of the base 1 is formed by subjecting the upper surface of a plate made of copper, copper-tungsten alloy or the like, which is the base 1, to the conventional grinding process. The upper surface is formed into a predetermined shape.

The base 1 having the projection 1a on the upper surface is also attached with the insulating frame 2 so as to surround the projection 1a on the upper surface.

The insulating frame 2 acts as a supporting member for supporting the metallized wiring layer 5 connecting each electrode of the semiconductor element 4 described later to an external electric circuit, and is made of an electrically insulating material such as an aluminum oxide sintered body. Is formed by.

When the insulating frame 2 is made of an aluminum oxide sintered body, for example, alumina, silica, calcia, magnesia, and the like are mixed with a suitable organic solvent and a solvent to form a slurry. A ceramic green sheet (ceramic green sheet) is formed by adopting a doctor blade method or a calendar roll method for this, and thereafter, appropriate punching processing is performed on the ceramic green sheet and a plurality of layers are laminated if necessary,
It is manufactured by firing at high temperature.

On the lower surface of the insulating frame body 2, a metallized metal layer 6 made of a refractory metal powder such as tungsten, molybdenum, manganese, etc. is adhered and formed. The insulating frame body 2 is attached to the base body 1 by brazing with the brazing material 7.

Further, the insulating frame 2 is provided with a cutout portion B at an inner peripheral corner portion of the lower surface, and the cutout portion B is provided on the base body 1 with the insulating frame body 2.
When attaching, it is effectively prevented that the inner peripheral corner portion B of the lower surface of the insulating frame body 2 is caught by the bulging portion formed between the upper surface of the base body 1 and the base portion of the protrusion 1a and becomes oblique. This has the effect that the insulating frame body 2 is horizontally attached to the base body 1. In this case, since the insulating frame body 2 is horizontally attached on the base body 1 by the notch B formed in the inner peripheral corner portion of the lower surface of the insulating frame body 2, the upper surface of the base body 1 and the lower surface of the insulating frame body 2 are Are in close contact with each other, and as a result, the bonding strength between the base body 1 and the insulating frame 2 is strengthened, and the occurrence of airtightness in the bonded portion is eliminated.

The cutout portion B formed in the insulating frame body 2 is formed, for example, by cutting a portion located at an inner peripheral corner portion of the lower surface of the ceramic green sheet to be the insulating frame body 2 in advance with a cutter or the like. 2 is formed on the inner peripheral corner of the lower surface.

Further, a plurality of metallized wiring layers 5 are adhered and formed on the upper surface of the insulating frame 2, and each electrode of the semiconductor element 4 is bonded to one end of the metallized wiring layer 5 via a bonding wire 8. An external lead terminal 9 electrically connected to the other end and electrically connected to an external electric circuit is brazed.

The metallized wiring layer 5 on the upper surface of the insulating frame 2 and each electrode of the semiconductor element 4 are bonded with a bonding wire 8
When electrically connected via, the insulating frame body 2 is horizontally attached to the base body 1, so that the distance between each electrode of the semiconductor element 4 and each metallized wiring layer 5 becomes uniform, and as a result, By making the lengths of the bonding wires 8 uniform, the characteristic impedances of the wirings composed of the bonding wires 8 and the metallized wiring layer 5 can all be matched, and there will be no significant loss in signal propagation.

The metallized wiring layer 5 is a semiconductor device.
It connects each electrode of 4 to the external lead terminal 9,
The metallized wiring layer 5 is made of a refractory metal powder such as tungsten, molybdenum, manganese, etc. The refractory metal powder such as tungsten is mixed with a suitable organic solvent and a solvent to obtain a metal paste, which becomes the insulating frame 2. Insulation frame is formed by applying the well-known screen printing method to the ceramic green sheet in advance and printing and applying it in a predetermined pattern.
It is deposited on the upper surface of 2.

Further, an external lead terminal 9 is brazed and attached to one end of the metallized wiring layer 5 via a brazing material such as silver brazing, and the external lead terminal 9 is attached to each of the semiconductor elements 4 housed inside. It functions to electrically connect the electrodes to an external electric circuit and is made of a metal material such as Kovar metal (iron-nickel-cobalt alloy) or 42 alloy (iron-nickel alloy).

The external lead terminal 9 is formed in a predetermined plate shape by adopting a conventionally known metal processing method such as a conventionally known rolling processing method or a punching processing method for an ingot (lump) of Kovar metal or the like. It

The external lead terminals 9 are formed by depositing a metal having good corrosion resistance such as nickel and gold on the exposed surface thereof and having good conductivity and having a thickness of 1.0 to 20.0 μm by a plating method. Oxidation and corrosion of the terminal 9 can be effectively prevented, and good electrical connection between the external lead terminal 9 and the external electric circuit can be achieved. Therefore, it is preferable that nickel, gold or the like is layered on the exposed surface of the external lead terminal 9 in a thickness of 1.0 to 20.0 μm.

Thus, according to the package for accommodating semiconductor elements of the present invention, the semiconductor element 4 is mounted and fixed on the protruding portion 1a of the base body 1, and each electrode of the semiconductor element 4 is bonded via the bonding wire 8 to the insulating frame 2 To the metallized wiring layer 5 of the substrate 1. Then, the lid 3 is joined to the insulating frame 2 on the substrate 1 via a sealing material made of glass, resin, etc.
The semiconductor device as a product is completed by hermetically sealing the semiconductor element 4 inside the container including the insulating frame 2 and the lid 3.

The present invention is not limited to the above-mentioned embodiments, and various modifications can be made without departing from the scope of the present invention. For example, in the above-mentioned embodiments, the base 1
Was formed of a metal material such as copper or a copper-tungsten alloy, but the thermal conductivity of an aluminum nitride sintered body was 150 W / m
It may be formed of an inorganic material of K or more. In this case, the base body 1 and the insulating frame body 2 are attached to each other by depositing a metallized metal layer made of a metal powder such as tungsten or molybdenum on the upper surface of the base body 1 in advance.
2 This is performed by brazing the metallized metal layer 6 on the lower surface with a brazing material 7 such as silver brazing.

[0031]

According to the package for accommodating semiconductor elements of the present invention, since the notch is formed at the inner peripheral corner of the lower surface of the insulating frame, the projecting portion is formed on the heat conductive substrate having the projecting portion on the upper surface. When the insulating frame is mounted so as to surround the base, the inner peripheral corners of the lower surface of the insulating frame become slanted by being caught by the bulging portion formed between the upper surface of the base and the base of the protrusion. As a result, the insulating frame horizontally adheres to the thermally conductive substrate, the bonding strength between the substrate and the insulating frame becomes extremely strong, and no airtightness occurs at the bonded portion.

Further, since the insulating frame is horizontally attached on the heat conductive substrate, a bonding wire for electrically connecting each electrode of the semiconductor element and each metallized wiring layer formed on the upper surface of the insulating frame. The lengths of all are equal, and as a result, it is possible to match all the characteristic impedances of the wiring composed of the bonding wire and the metallized wiring layer,
There is no significant loss in signal propagation.

[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 cross-sectional view of a main part of the package shown in FIG.

FIG. 3 is a cross-sectional view of a conventional semiconductor element housing package.

4 is an enlarged cross-sectional view of a main part of the package shown in FIG.

[Explanation of symbols]

 1 ... Insulating substrate 1a ... Protrusions 2 ... Insulating frame 3 ... Lid 4 ... Semiconductor element B ... Notch

Claims (1)

[Claims] 1. A package for accommodating a semiconductor element, comprising a heat conductive base having a protrusion on which a semiconductor element is mounted, and an insulating frame body attached to the protrusion so as to surround the protrusion. A package for accommodating a semiconductor element, wherein a notch is formed at an inner peripheral corner of the lower surface of the insulating frame.