JP3146428B2 - Metal composite material and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a metal composite material,
More specifically, the present invention relates to a metal composite material used for an electrode material for supporting a semiconductor element or a substrate for mounting a semiconductor element, and a method for manufacturing the same.

[0002]

2. Description of the Related Art Generally, a heat sink made of aluminum is widely used in semiconductor devices. There are also many semiconductor integrated circuit devices in which a semiconductor integrated circuit is mounted on a ceramic substrate and the ceramic substrate is mounted on a heat sink.

[0003]

When the above-mentioned semiconductor integrated circuit device is formed, a material close to the thermal expansion coefficient of the semiconductor material such as silicon constituting the semiconductor integrated circuit, for example, a single material such as molybdenum or tungsten, or ,copper/
Composite materials such as molybdenum and copper / tungsten have been used as the material of the heat sink, but this type of semiconductor integrated circuit device has a problem in that the heat sink is heavy and light.

On the other hand, recently, there has been an increasing demand for weight reduction of semiconductor integrated circuit devices.

As described above, in a semiconductor integrated circuit device which emphasizes weight reduction, not only a substrate supporting the semiconductor integrated circuit but also a heat radiating plate is required to be light. In order to meet such demands, it is necessary to make the heatsink a relatively low-density material, that is, a light material. However, a low-density material is generally less than a semiconductor material such as silicon. At present, a radiator plate capable of meeting the above-mentioned demand for weight reduction has not yet been disclosed because of its high coefficient of thermal expansion.

More specifically, according to experiments performed by the present inventors, in order to meet the demand for weight reduction, it is inappropriate to have a thermal expansion coefficient and a thermal conductivity of 23.0 × 10 ⁻⁶ or more. However, it was found that if the coefficient of thermal expansion was about 10 × 10 ⁻⁶ / ° C., it could be sufficiently used.

Accordingly, it is an object of the present invention to provide a metal composite material which can meet the demand for weight reduction and has a sufficient coefficient of thermal expansion and thermal conductivity, and a method for producing the same.

[0008]

Means for Solving the Problems The present inventors diligently develop a practical composite material based on a ductile metal-based composite material, which is firstly lightweight, inexpensive, and has desired thermal characteristics. As a result of our efforts, we have found a stable combination of Al and Mo or W.

In particular, since Al (ell) has poor wettability with brazing filler metal solder, plating or cladding is applied, and for Mo, the wire is simply sandwiched in a grid shape (hereinafter referred to as a grid wire). When the wire is formed into a net, a composite component having a so-called Al (ell) .Mo.Al (ell) laminated structure can be provided relatively easily.

According to the present invention, the base material is molybdenum,
The molybdenum base material has a laminated structure of Al.Mo.Al using aluminum as a joining material, has a coefficient of thermal expansion of 10 × 10 ^{−6 to} 23.0 × 10 ⁻⁶ / ° C. A metal composite material characterized by being at least one of a wire in a shape and a wire in a lattice shape is obtained.

In this case, if the Ni wire or the Ni thin plate is press-bonded to the Mo wire with a clad, for example, the pores (air pockets) at the time of joining Al (Mo) with Mo become Al.
(L) -Mo can be completely eliminated because the wettability of Mo is improved. Also, as a method of matching with Al (L) -Mo,
What is necessary is just to roll at a cold or warm state, and what was made into a net | network shape is preferable because it can follow the expansion | extension of Al (ell) when it forms a board | substrate.

According to the present invention, the metal composite material is characterized in that the bonding material is plated or clad for improving soldering or brazing properties.

According to the present invention, aluminum is used as a matching material for a base material made of at least one of the mesh-like molybdenum wire and the lattice-like molybdenum wire.
A method for producing a metal composite material, characterized by stacking and rolling to obtain Mo · Al, is obtained.

According to the present invention, in the metal composite material, the composite material is subjected to plating or cladding for improving solderability or brazing property. Is obtained.

When the metal composite material of the present invention is used for a purpose other than a heat-radiating substrate, the coefficient of thermal expansion is in accordance with the above-mentioned market requirements (10-23.0 × 10 ⁻⁶ / ° C .;
5 below (Al (El) 1/2 or less of the ₂ O ₃ or Mo))
When aiming at an area below or smaller than the above, it is preferable to stack the grid lines or nets in two or more layers without increasing the wire diameter of Mo.

[0016]

Embodiments of the present invention will be described below.

Example 1 A net having a nominal size of 710 μm was prepared from a Mo wire having a wire diameter of 0.450 mm. Since the surface graphite has already been removed, general wet nickel plating is applied to give a layer thickness of 0.5 μm. Next, the mesh is sandwiched between two 10 mm thick Al plates.
Rolling at 0 ° C until the total layer thickness becomes 10mm
processed. In addition, cold rolling was added to increase the surface flatness. With this, the so-called Mo net is used as the base material,
A three-layer composite material using Al as a composite material was obtained.

FIG. 1 is a micrograph showing a metal structure of a metal composite material according to an example of the present invention. As shown in this photograph, it can be seen that no pore is found around the Mo line.

Here, Ni (Al) is plated with Ni by a zinc substitution method. After the surface is degreased, it is immersed in a commercially available alkaline replacement solution (AL-20, World Metal Co., Ltd.) for 30 seconds at 40 ° C., and then etched with a HNO ₃ -based acid solution to remove smut (AZM-201, Uemura Kogyo). After this, NaO
A surface treatment is performed with a zinc-substituted solution (Hizai Chemical, Super Zincate) containing H, ZnCl (L) ₂ as a main component, and finally, Ni plating is performed at 1 A / dm ² in a Watt bath.
After taking out and washing, the film was baked in hydrogen at 410 ° C. for 20 minutes to obtain a Ni plating thickness of 1 μm.

When the characteristics of the test piece were examined, the density was 2.9.
g / cm ³ , coefficient of thermal expansion 11.9 × 10 ⁻⁶ / ° C., and thermal conductivity 0.40 cal / cm · sec · ° C.

Consider W as a comparative example. From the standpoint of mass production stability of W-plates, the thickness of easy-to-use plates is limited to 0.1 mm. When a composite material having a three-layer structure of Al (Well) / W · Al (Well) was trial-produced to increase the density to 4.4 g / cm ³ , which is 1.5 times that of Example 1, the thermal expansion coefficient was 8. 0 × 10 ^-6 /
° C, which is much lower than the desired relatively large coefficient of thermal expansion that matches the material around the substrate, making it unsuitable.

[0022]

As described above, the metal composite material of the present invention can provide a metal composite material having no internal pores and the like and excellent in mass production stability, and a method for producing the same.

Further, according to the present invention, the joining material is Al
(G), and a composite part with good grindability and a method for producing the same can be provided.

Moreover, according to the present invention, it is possible to provide a metal composite material for a heat radiation board which is lightweight and has good solder brazing properties, and a method for producing the same.

Further, according to the present invention, it is possible to provide a metal composite material whose characteristics can be freely adjusted in a range having a relatively large coefficient of thermal expansion, for example, 10 to 23 × 10 ⁻⁶ / ° C., and a method for producing the same. it can.

In addition, there is a possibility that this kind of metal composite material can be converted to a material which focuses on thermal expansion, although not related to the above-described semiconductor device and the above-mentioned metal composite material.

[Brief description of the drawings]

FIG. 1 is a micrograph showing a metal structure of a metal composite material according to an example of the present invention.

────────────────────────────────────────────────── ─── Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B32B 15/01 B23K 20/04

Claims (4)

(57) [Claims] 1. A laminated structure of Al.Mo.Al with a base material of molybdenum and a bonding material of aluminum,
It has a coefficient of thermal expansion of 10 × 10 ^{−6 to} 23.0 × 10 ⁻⁶ / ° C., and the molybdenum base material is at least one of a mesh wire and a grid wire. Metal composite material. 2. The metal composite material according to claim 1, wherein
A metal composite material, wherein the bonding material is plated or clad for improving solderability or brazing property. 3. A method in which aluminum is superimposed on a base material made of at least one of a mesh-like molybdenum wire and a lattice-like molybdenum wire so as to become Al.Mo.Al, and rolled. A method for producing a metal composite material characterized by the following. 4. The metal composite material according to claim 3,
A method for manufacturing a metal composite material, wherein the bonding material is subjected to plating or cladding for improving soldering or brazing properties.