JPS6245050A - Substrate for semiconductor device - Google Patents

Abstract

PURPOSE:To contrive to improve the insulation property and chemical resistance of the titled substrate by forming an insulating coating consisting of a high- melting point glass on the high-heat conductive substrate consisting of a specific metal. CONSTITUTION:An insulating coating 2 consisting of a high-melting point glass having a softening point of 600 deg.C or more and a thickness of 3-30mum is formed on a high-heat conductive substrate 1 consisting of a metal whose thermal expansion coefficient is 1X10<-6>-11X10<-6>cm/dcg and whose thermal conductivity is 0.1Cal/cm.sec.k or more. The insulative coating can be also formed by coating indirectly through a metal layer besides being formed by coating directly on the high-heat conductive substrate. This substrate for a semiconductor device is superior in heat conductivity and heat dissipation property and displays a favorable insulation property and chemical resistance at a high-temperature region as well.

Description

Detailed Description of the Invention 3. 37:1 [1 Description (Field of Industrial Application)] This invention relates to a substrate for a semiconductor device, and particularly to a substrate for a semiconductor device suitable as a heat dissipation substrate for mounting an IC. .

<Background and Prior Art> Conventionally, heat dissipation substrates made of metals with good thermal conductivity have been provided as substrates for semiconductor devices. The above-mentioned heat dissipation substrate is used for the purpose of dissipating heat effectively, in view of the fact that the amount of heat generated from semiconductor elements increases as the density of integrated circuits increases, and insulation is required in the design. In this case, an insulating MPM is formed by bonding an insulating sheet to a metal substrate having good thermal conductivity or by a vapor phase method.

<Problems to be solved by the invention> However, when the insulating sheets are bonded together, it is necessary to interpose an adhesive between the fully bent substrate and the insulating sheet, and the insulating sheet itself There is a problem in that high thermal conductivity cannot be obtained because it is difficult to make the wall thin. There is also the problem that the manufacturing process is complicated and the cost is high.

On the other hand, when a thin film is formed by a vapor phase method, micro-destruction occurs in the thin film due to phase transition, recrystallization, thermal stress due to a difference in thermal expansion coefficient, etc. in the thin film in a high temperature region. There are problems in that insulation properties deteriorate and chemical resistance cannot be exhibited.

The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a substrate for a semiconductor device that has excellent thermal conductivity and can exhibit good insulation and chemical resistance even in a high temperature range.

Means for Solving the Problems> The substrate for a semiconductor device of the present invention for achieving the above object has a thermal expansion coefficient of lX10-6 to 11X10.
'cm/dcgt', thermal conductivity force, 0.1cat
/Cm-Sec -k or higher, a highly thermally conductive substrate made of a metal with a softening point of 600°C or higher and a thickness of 3 to 30°C.
An insulating film made of high melting point glass is formed.

However, the above-mentioned insulating film can be formed not only directly on the highly thermally conductive substrate but also indirectly through the gold B layer. In addition, as a thermally conductive substrate,
Cu-W alloy, Cu-M.

It is conceivable to form it with an alloy, Δ1-Si alloy, or the like.

Effects> According to the semiconductor device substrate, heat generated by the semiconductor element can be efficiently dissipated through the highly thermally conductive substrate and the insulating film made of high melting point glass. Also,
The insulation and chemical resistance of the insulating film in a high temperature region can be stably ensured using high melting point glass.

<Example> Embodiments will be described in detail below with reference to the accompanying drawings showing examples.

FIG. 1 is a sectional view showing a semiconductor device substrate in which one side of a highly thermally conductive substrate (1) is directly coated with an insulating film (2) made of high melting point glass.

The high thermal conductive substrate (1) has a thermal expansion coefficient of 1×
10 to 11 x 10-60 m/deg and a metal with a thermal conductivity of 0, I Cat /ca+-sec-k or more, such as Cu-W alloy, Cu-MO alloy, AI-
It is made of Si alloy or the like. By regulating the thermal expansion coefficient within the above range, it is possible to prevent microscopic destruction of the insulating film (2) caused by differences in thermal coefficients.Also, the thermal conductivity can be reduced to 0.1 Cal/cm. 5ec・k
By doing so, the heat generated by the semiconductor element (3) mounted on the highly thermally conductive substrate (1) can be efficiently transferred.

The insulating coating ('2J) must not melt when the ceramic (4) serving as the connection terminal is brazed to the highly thermally conductive substrate (1).
As the high melting point glass, glass having a softening point of 600° C. or higher is used. Furthermore, the coating thickness of the insulating wave Ill (21) is set in the range of 3 to 30 μm, so that stable insulation and heat dissipation properties can be obtained.

That is, if the coating thickness of the insulating coating (2) is 3 μa > li, there is a risk of insulation failure;
Otherwise, the dissipation of conductive heat from the highly thermally conductive substrate (1) will be inhibited.

With the above configuration, the insulating film (2) can exhibit stable insulation in the temperature range of at least 600° C.Jf-t. Furthermore, since the high melting point glass used as the insulating coating (2) has chemical resistance such as alkali resistance and acid resistance, Si chip bonding and Au plating for improving oxidation resistance are possible.

Note that the present invention is not limited to the above-mentioned embodiments, and for example, as shown in FIG. 9
Various design changes can be made without changing the gist of the present invention, such as coating the material through a wire.

Comparative Example> A highly thermally conductive substrate (1) was prepared using a Cu-W alloy (10 to 15% by weight Cu) and a Cu-MO alloy (10 to 15% by weight).
The following table shows the performance test results of substrates for semiconductor devices in which these highly thermally conductive substrates (1) were directly coated with an insulating coating (Z) with a thickness of 2 to 28 μm. The insulating wave M (21) was made by screen printing glass paste (softening point: 850°C) and firing it at 950°C.

From the comparative example above in the table, the coating thickness of the insulating coating (2) is 3 to 3.
It can be inferred that good insulation and thermal conductivity can be obtained in the range of 0.077 m.

<Effects of the Invention> As described above, the semiconductor device substrate of the present invention has the unique effects of being excellent in thermal conductivity and heat dissipation, and also exhibiting good insulation and chemical resistance even in high-temperature areas. play.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a substrate for a semiconductor device, and FIG. 2 is a sectional view showing another example of actual flow. (1)...High thermal conductivity substrate (2)...Insulating coating (5)...Metal layer

Claims (1)

[Claims] 1. Coefficient of thermal expansion is 1×10^-^6 to 11×10^-^
At 6cm/deg, the thermal conductivity is 0.1Cal/cm・s
For semiconductor devices, characterized in that an insulating film made of high melting point glass having a softening point of 600° C. or more and a thickness of 3 to 30 μm is formed on a highly thermally conductive substrate made of a metal of ec・k or more. substrate. 2. The semiconductor device substrate according to claim 1, wherein the insulating film is formed directly on the highly thermally conductive substrate. 3. The semiconductor device substrate according to claim 1, wherein the insulating film is indirectly formed on the highly thermally conductive substrate via a metal layer. 4. The substrate for a semiconductor device according to claim 1, wherein the highly thermally conductive substrate is a Cu-W alloy. 5. The substrate for a semiconductor device according to claim 1, wherein the highly thermally conductive substrate is a Cu-Mo alloy. 6. The substrate for a semiconductor device according to claim 1, wherein the highly thermally conductive substrate is an Al-Si alloy.