JPH0525722U - Package for storing semiconductor devices - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a package for housing a semiconductor element in which the mounting and fixing of the semiconductor element is firm. [Structure] Semiconductor element mounting portion of metal base 1 forming a container
In the semiconductor element housing package, in which the semiconductor element 4 is attached and fixed via the metal plate 5 on 1a and the semiconductor element 4 is housed in the container, the metal plate 5 has nickel films 5b on both upper and lower surfaces, A punched molybdenum plate 5a to which 5b is joined is used, and the punching end surface is placed on the semiconductor element 4 side and sandwiched between the semiconductor element 4 and the semiconductor element mounting portion 1a of the metal base 1. . When the metal plate 5 is attached to the semiconductor element mounting portion 1a of the metal substrate 1 via the brazing material 11, a part of the brazing material 11 does not creep up the side surface of the metal plate 5 and flow out to the upper surface. As a result, the semiconductor element 4 can be firmly fixed to the upper surface of the metal plate 5.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a semiconductor device storage package for housing a semiconductor device, particularly a semiconductor integrated circuit device.

[0002]

[Prior Art]

 2. Description of the Related Art In recent years, as the performance of information processing apparatuses has increased, the semiconductor elements that make up the information processing apparatuses have been rapidly increasing in density and integration. Therefore, the amount of heat generated per unit volume and unit volume of semiconductor devices increases during operation, and how to efficiently remove the heat is a challenge for normal and stable operation of semiconductor devices. ing.

Conventionally, as a method of removing heat generated by a semiconductor element, for example, the method described above is used on a metal base made of a copper-tungsten alloy having a mounting portion on which a semiconductor element is mounted and fixed in a central portion of an upper surface. A semiconductor element housing package having a structure in which an insulating frame made of alumina ceramics is attached so as to surround the mounting portion through a brazing material such as silver solder is prepared, and the semiconductor element is mounted on the semiconductor element mounting portion of the metal base. Is mounted and fixed via a metal plate, the heat generated from the semiconductor element is absorbed by the metal substrate, and the absorbed heat is released to the atmosphere.

A metal wiring layer is embedded in the insulating frame, so that each electrode of the semiconductor element housed inside can be electrically connected to an external electric circuit through the metal wiring layer. It has become.

Further, the metal plate interposed between the semiconductor element mounting portion of the metal base and the semiconductor element is made of molybdenum, and acts to relieve thermal stress caused by the difference in thermal expansion coefficient between the semiconductor element and the metal base. To do.

For the metal plate, a molybdenum plate obtained by rolling is punched into a predetermined shape by a punching method, and the metal plate is firmly attached to a semiconductor element mounting portion of a metal substrate. The burr surface (finishing surface) formed during punching is attached to the semiconductor element mounting part of the metal base with the semiconductor element side as the semiconductor element side, and the semiconductor element can be easily attached to the metal plate on the entire outer surface of the metal plate. In addition, nickel plating and gold plating are applied to firmly attach and fix.

[0007]

[Problems to be solved by the device]

 However, in this conventional package for accommodating semiconductor elements, the brazing material such as nickel plating or gold plating and a metal having good wettability are adhered to the outer surface of the metal plate, so that the metal plate is mounted on the semiconductor substrate of the metal base. When a brazing material such as silver brazing is attached to the metal part, a part of the brazing material creeps up on the side surface of the metal plate and flows out to the upper surface, and as a result, the semiconductor element is firmly attached to the upper surface of the metal plate. It had a drawback that it could not be attached and fixed.

[0008]

[Means for Solving the Problems]

 The present invention relates to a semiconductor device housing package in which a semiconductor device is mounted and housed through a metal body in a container, wherein the metal plate is a punched molybden board having nickel films bonded on both upper and lower surfaces, and This is characterized in that the punching end surface is on the semiconductor element side.

[0009]

【Example】

 Next, the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a sectional view showing an embodiment of a package for housing a semiconductor device according to the present invention, in which 1 is a metal base, 2 is an insulating frame, and 3 is a lid. The metal base 1, the insulating frame body 2 and the lid body 3 constitute a container for housing a semiconductor element.

The metal base 1 is provided with a convex mounting portion 1a on which a semiconductor element is mounted on the center of the upper surface thereof, and the semiconductor element 4 and the metal plate 5 are mounted on the convex mounting portion 1a. It is fixed by sandwiching it.

The metal base 1 absorbs the heat generated by the semiconductor element 4 and at the same time releases the absorbed heat into the atmosphere, so that a large thermal stress is generated between the metal base 1 and the insulating frame 2 described later. It is formed of a material having a thermal expansion coefficient close to that of the insulating frame 2 and a good thermal conductor, for example, a copper-tungsten alloy (Cu-W alloy).

The metal substrate 1 made of the copper-tungsten alloy is formed, for example, by pressing tungsten powder (about 10 μm) at a pressure of 1000 kg / cm ² and pressurizing the powder at a temperature of about 2300 ° C. in a reducing atmosphere. It is formed by firing to obtain a porous tungsten sintered body, and then impregnating the porous portion of the tungsten sintered body with capillary phenomenon by utilizing the heat-melted copper at a temperature of 1100 ° C.

Further, an insulating frame body 2 is attached to the outer periphery of the upper surface of the metal base 1 so as to surround a convex mounting portion 1 a provided on the upper surface of the metal base 1. The insulating frame 2 and the insulating frame 2 form a space for housing the semiconductor element 4.

The insulating frame 2 is made of an electrically insulating material such as alumina ceramics. For example, a powder of aluminum ceramics is mixed with an appropriate organic solvent or solvent to form a sludge, and a doctor blade method is adopted. Ceramic green sheet (ceramic green sheet) is formed by using the above method, and then the ceramic green sheet is subjected to appropriate punching processing, laminated with multiple sheets, and baked at high temperature (about 1600 ° C). It

A metallized metal layer 6 made of a high melting point metal powder such as tungsten or molybdenum is deposited on the lower surface of the insulating frame 2, and the metallized metal layer 6 and the metal substrate 1 are made of silver solder or the like. It is attached to the metal substrate 1 by brazing with the brazing material 7.

Inside the insulating frame 2, a conductive layer 8 made of a high melting point metal powder such as molybdenum or tungsten is provided, and the conductive layer 8 connects the electrode of the semiconductor element 4 to the external lead pin 9. The external lead pin 9 is attached to one end thereof, and the bonding wire 10 connected to the electrode of the semiconductor element 4 is attached to the other end thereof.

The external lead pins 9 attached to the conductive layer 8 provided on the insulating frame 2 serve to connect the respective electrodes of the semiconductor element 4 housed inside to an external electric circuit, and the Kovar metal (Fe- A metal such as Ni-Co alloy) or 42 alloy (Fe-Ni alloy) processed into a rod shape is used.

It should be noted that if 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 9 by plating to a thickness of 2 to 20 μm, the external lead pin 9 The electrical connection between 9 and the external electric circuit is good, and oxidative corrosion of the external lead pin 9 is effectively prevented. Therefore, in order to prevent the oxidative corrosion of the external lead pins 9 and to improve the electrical connection with the external electric circuit, the outer surface of the external lead pins 9 is made of nickel, gold, etc., having good conductivity and excellent corrosion resistance. It is preferable that the metal is layered to a thickness of 2 to 20 μm.

As shown in FIG. 2, the metal substrate 1 having the insulating frame 2 attached to the upper surface thereof has the semiconductor element 4 attached to the semiconductor element mounting portion 1a with the metal plate 5 interposed therebetween. Fixed.

The metal plate 5 sandwiched between the semiconductor element mounting portion 1 a of the metal base 1 and the semiconductor element 4 serves to relieve thermal stress caused by the difference in thermal expansion coefficient between the metal base 1 and the semiconductor element 4. Therefore, the nickel films 5b and 5b are bonded to both upper surfaces of the molybdenum plate 5a.

The metal plate 5 is formed, for example, by pressing a nickel thin plate on both upper and lower surfaces of a plate made of molybdenum by a conventionally known rolling process and punching this into a predetermined shape by a punching process. The plate 5 has the starting surface for punching on the side of the semiconductor element mounting portion 1a of the metal substrate 1 and the end surface for punching on the side of the semiconductor element 4 on the upper surface of the semiconductor element mounting portion 1a of the metal substrate 1 with a brazing material 11 such as silver solder interposed therebetween. Be attached. In this case, the brazing material and the nickel film having good wettability are arranged on the upper and lower surfaces of the metal plate 5, but the brazing material and molybdenum having poor wettability are exposed on the side surfaces of the metal plate 5, so that the metal plate 5 is made of metal. When attaching to the semiconductor element mounting part 1a of 1, the brazing material 11 does not creep up on the side surface of the metal plate 5 and flows out to the upper surface at all. The element 4 can be fixed extremely firmly.

Since the brazing material and the nickel film 2b having good wettability are bonded to the upper surface of the metal plate 5, the semiconductor element 4 can be firmly attached and fixed to the metal plate 5, and as a result, It is possible to fix the semiconductor element 4 on the semiconductor element mounting portion 1a of the metal base 1 extremely firmly.

Further, when the metal plate 5 is formed by punching, a curved chamfer is formed on the outer peripheral portion on the punching start surface side, which cuts the metal plate 5 on the semiconductor element mounting portion 1a of the metal substrate 1. At the time of attachment, a large amount of brazing material 11 can be allowed to intervene between the metal plate 5 and the semiconductor element mounting portion 1a of the metal base 1 to make the attachment of both materials stronger.

When the thickness of the nickel films 5b, 5b bonded to the upper and lower surfaces of the molybdenum plate 5a exceeds 50 μm, the nickel plate 5b is formed due to the ductility of nickel when it is formed by punching. The molybdenum plate 5a cannot be effectively stretched and adhered to the side surface of the molybdenum plate 5a, and the creeping up of the brazing material 11 cannot be effectively prevented. Therefore, it is preferable that the nickel films 5b and 5b of the metal plate 5 have a thickness of 50 μm or less.

Thus, according to the semiconductor element housing package of the present invention, the semiconductor element 4 is attached and fixed to the metal plate 5 attached to the semiconductor element mounting portion 1a of the metal substrate 1, and each semiconductor element 4 is attached. By connecting the electrodes to the conductive layer 8 via the bonding wires 10 and attaching the lid 3 to the upper surface of the insulating frame 2 via a sealing material, a semiconductor device as a final product is obtained.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, the nickel film 5b is formed on both upper and lower surfaces of the molybdenum plate 5a. , 5b may be replaced by pressure bonding by a conventionally known rolling method, and nickel plating may be applied to both upper and lower surfaces of the molybdenum plate 5a to bond the nickel films 5b, 5b having a predetermined thickness. In this case, when the nickel films 5b, 5b formed by plating become thin with a thickness of less than 7 μm, a large number of film defects are formed, and the metal plate 5 is firmly brazed to the semiconductor element mounting portion 1a of the metal substrate 1. Difficult to wear. Therefore, when the nickel films 5b, 5b are bonded to the upper and lower surfaces of the molybdenum plate 5a by plating, the thickness thereof is preferably set to 7 μm or more and 50 μm or less.

In the above-described embodiment, the semiconductor element housing package in which the semiconductor element 4 is attached to the semiconductor element mounting portion 1a of the metal substrate 1 with the metal plate 5 sandwiched therebetween is described. The present invention can also be applied to a semiconductor element housing package in which a concave portion for accommodating a semiconductor element is provided in the insulating base body and the semiconductor element 4 is attached with the metal plate 5 sandwiched in the concave portion.

[0029]

[Effect of the device]

 According to the package for housing a semiconductor element of the present invention, a metal plate to which a semiconductor element is directly attached is punched into a predetermined shape from a molybdenum plate having nickel films bonded on both upper and lower surfaces. When brazing and attaching to the semiconductor element mounting part of the metal substrate, part of the brazing material does not climb up the side surface of the metal plate and flows out to the upper surface at all, and as a result, the semiconductor element is mounted on the upper surface of the metal plate. Can be firmly fixed.

Further, when the metal plate is formed by punching, a curved chamfer is formed on the outer peripheral portion on the punching start surface side, and when the metal plate is brazed and attached to the semiconductor element mounting portion of the metal substrate, A large amount of brazing material is allowed between the metal plate and the semiconductor element mounting part of the metal base to strengthen the attachment of both, thereby mounting and fixing the semiconductor element on the semiconductor element mounting part. Can be made stronger.

[Brief description of drawings]

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

FIG. 2 is an enlarged cross-sectional view of a main part of the semiconductor element storage package shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Metal base 1a ... Semiconductor element mounting part 2 ... Insulating frame 3 ... Lid 5 ... Metal plate 5a ... Molybdenum plate 5b ... Ni film

Claims (1)

[Scope of utility model registration request] 1. A semiconductor element housing package for mounting and housing a semiconductor element via a metal body inside a container, wherein the metal plate is a punched molybdenum plate having nickel films bonded to both upper and lower surfaces, Also, a package for housing a semiconductor element, wherein the punching end surface is on the semiconductor element side.