JPH0226057A - Heat radiation plate - Google Patents

Abstract

PURPOSE:To obtain an improved heat conduction by forming a diamond-shaped substance layer on a substrate consisting of dispersion strengthened type alloy made by dispersing a metal oxide particle into a matrix of copper or copper alloy. CONSTITUTION:A substrate consists of a dispersion strengthened type alloy made by dispersion a metal oxide particle into a matrix of copper or copper alloy. Copper alloy constituting this matrix is an alloy which mainly consists of copper such as Cu-Al and Cu-Zn. Then, a diamond-shaped substance layer is formed on a substrate consisting of a dispersion strengthened type alloy and the formation of this diamond-shape substance layer is performed by the gaseous phase growth method. It achieves a high coherency between the substrate and the diamind-shaped substance layer even after heating cycle history, thus obtaining an improved heat conduction as a whole.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat sink used in devices such as semiconductor lasers, IC packages, hybrid ICs, and Peltier elements.

[Conventional technology]

Conventionally, as a heat sink for devices such as semiconductor lasers, IC packages, and hybrid IC1 Peltier devices,
Materials made of copper, copper alloys, single crystal diamond, etc. have been used. However, heat sinks made of materials other than single-crystal diamond do not have sufficient thermal conductivity, so there is a problem that they cannot adequately respond to higher output or higher integration of devices. On the other hand, heat sinks made of single-crystal diamond do not have any problems with thermal conductivity, but they have the problem of being expensive and difficult to obtain in large quantities.

However, in recent years, hot filament method, plasma C
For example, 20JAff1 is produced by a vapor phase growth method such as a VD method.
It is now possible to produce a diamond-like material layer with a thickness greater than 100%, and since this diamond-like material layer has thermal conductivity more than twice that of copper, it is expected to be used as a material for heat sinks for devices. ing. However, the diamond-like material layer described above is formed on a substrate such as a silicon wafer, quartz glass, or tungsten carbide, but these substrates have low thermal conductivity, so the overall thermal conductivity is low. Therefore, it cannot be used as a useful heat sink as it is.

Therefore, attempts have been made to obtain a heat sink by using copper or a copper alloy with high thermal conductivity as a substrate and forming a diamond-like material layer thereon.

[Problem that the invention seeks to solve]

However, when using a substrate made of copper or copper alloy, it is not possible to obtain high adhesion between the formed diamond-like material layer and the substrate, resulting in peeling or cracking of the diamond-like material layer. However, there is a problem that high thermal conductivity cannot be obtained.

Based on the above circumstances, the present invention provides that the substrate on which the diamond-like material layer is formed has high thermal conductivity, and that the substrate and the diamond-like material layer have high adhesion even after thermal cycle history. It is an object of the present invention to provide a heat dissipation plate which has high thermal conductivity as a whole.

[Means for solving problems]

The heat dissipation coffin of the present invention is characterized by comprising a substrate made of a dispersion-strengthened alloy in which metal oxide particles are dispersed in copper or a copper alloy, and a diamond-like material layer formed on the substrate.

The substrate in the heat sink of the present invention is made of a dispersion-strengthened alloy in which copper or a copper alloy is used as a matrix, and metal oxide particles are dispersed in the matrix. Here, as the copper alloy forming the matrix, for example, C
u-Al, Cu-Zn, Cu-button, Cu-Ti,
Cu-5i1Cu-Ni, Cu-Cr5Cu-N+
-81, Cu-Ni-Mo and other copper-based alloys containing 50% by weight or more of copper, preferably 70-99.
The one containing 9% by weight is used.

Examples of metal oxide particles dispersed in these matrices include ^1203, SiO□, and Ti01Tin.
,,Tl2O,,C'aO1Br20*,HfO2
,Hg01Try2,t,'azL,Rh2Off,5
c203, Ni01The,, v205, Yb20+,
Particles made of 5rO1Se02, SeO, etc. are used.

Among these, 81203, SiO□, TlO2, etc. are particularly preferred.

In the present invention, the metal oxide particles in the dispersion-strengthened alloy forming the substrate are preferably finely dispersed, but the shape of the metal oxide particles is not particularly limited. Further, the dispersion state may be uniformly dispersed, or may have a gradient such that many metal oxide particles are dispersed on the surface of the matrix metal and less dispersed inside the matrix metal.

The particle size of the metal oxide particles in the matrix metal is, for example, within the range of 100A to 5-5, and the content thereof is, for example, 0.1 to 50% in volume fraction, preferably 2 to 40%. .

Examples of methods for producing dispersion-strengthened alloys include plasma method (US Pat. No. 4.701.301), lineback method (F, N, Rhnes Tr'ans,
Met.

Sac, A IME 137 (1940) 246
), and the mechanical alloying method in which metal oxide particles and copper or copper alloy particles are mixed and molded.Although there are no particular restrictions, the plasma method is preferred from the viewpoint of manufacturing efficiency. The internal oxidation method is preferred.

In this internal oxidation method using a plasma method, a material alloy is prepared by containing a metal to be selectively oxidized in a matrix metal made of copper or a copper alloy, and while heating this material alloy, oxygen and/or Gases of compounds containing oxygen atoms (hereinafter referred to as "oxygen-containing gases")
A method of selectively oxidizing metal elements other than the matrix metal in a material alloy by causing plasma generated in the presence of oxygen (hereinafter referred to as "oxygen-containing plasma") to act on the material alloy (hereinafter referred to as "internal oxidation method"). ). The material alloy used in this method can be made by a method such as a melting method or a sputtering method, and the manufacturing method is not particularly limited.

The selectively oxidized metal contained in the material alloy used in the above plasma method is ^1, C'a.

Er%Hf, Hg5Ir, L'aSRh, Sc,
Se, Si, N1, Th.

One or more selected from T1, V s YJ Sr, etc. can be used, but preferred are AI, Ti5S
i, N1, etc., and particularly preferred are Al5Ti,
81 etc.

The internal oxidation method using oxygen-containing plasma will be explained below.

The types of oxygen-containing gas used include 02, COi
,NO,,N2O3,N2O4,N2O3,SO□,S
03, TeO□, Teas, Sea, 5eas, P=
OIo,P,CI,,As2O5,AS,O,,5b2
0s, sb, o, , Bi, 05, Bi, 0. , H, G, etc. Also, I(elAr, Xe
A rare gas such as N2, N2.8□, etc. can also be added to the oxygen-containing gas as a carrier gas.

The degree of vacuum in the plasma generation space is lX10-'~1
00 Torr, more preferably 1X10-5 to 10 Torr. Vacuum degree is 1×1
If it is less than 0-' Torr or more than 100 Torr, it becomes difficult to generate plasma stably and uniformly.

Under such conditions, it is preferable that the partial pressure of the oxygen-containing gas is 1X10-5 to 1Q7orr,
Particularly preferred are IXIQ-5 to l Torr. If the partial pressure of the oxygen-containing gas is less than IX10-'Torr,
M) The oxidation rate of the metal to be oxidized in IJ Fuchs is extremely slow, and on the other hand, if it exceeds 10 Torr, the matrix metal may also be oxidized.

There are no particular limitations on the means, mode, device, etc. for generating oxygen-containing plasma. For example, the reactor can be a Pelger type, Chiny-Blar flow type, etc., and the types of discharge can be DC discharge, low frequency discharge, high frequency discharge, etc.
Any method such as microwave discharge or cathode heating type discharge may be used.
As the electrode, a parallel plate type, a coil type in the case of high frequency discharge, a hollow cathode type, etc. can also be used.

Furthermore, in the case of microwave discharge, electrodes with cavity couplings or ladder couplings may be used. Among these electrodes, specific examples of the coil type include cylindrical, square, and flat types.

The flow rate of the oxygen-containing gas when generating oxygen-containing plasma is preferably in the range of 0.1 to 100 cc (STP)/min, for example, when a plasma reactor with an internal volume of 1501 is used. The flow rate of oxygen-containing gas is 0.1
cc(STP)/min, the oxidation rate of the metal to be oxidized in the matrix metal is low, and 100
If it exceeds cc(STP)/min, there is a possibility that the matrix metal may also be oxidized.

In the internal oxidation method, it is necessary to heat the material alloy, and this heating is conveniently done by induction heating, but of course it is also possible to heat the material alloy from the outside using a heater, infrared rays, etc. .

When heating a material alloy by induction heating, there are no particular restrictions on the electrode, mode, device, etc. for performing induction heating. For example, the power supply frequency may be low frequency, high frequency, microwave, etc., but generally it is 50Hz to 300Hz.
0 MHz is preferred.

Generation of oxygen-containing plasma and induction heating can be performed simultaneously in the same container using a common electrode, or two or more electrodes can be used to perform plasma generation and induction heating independently or complementarily. It can also be done.

When producing the dispersion-strengthened alloy used as the substrate in the present invention by the internal oxidation method described above, the temperature of the material alloy only needs to be 500° C. or higher.

The heat sink of the present invention is constructed by forming a diamond-like material layer on the surface of a substrate made of the above dispersion-strengthened alloy. This diamond-like material layer is formed by a vapor phase growth method, but the specific method is not particularly limited. Therefore, for example, microwave plasma method (M, K button o, Y, S≧tO, S.

Mhtsumoto knd N, 5etkk:
a: Jor, Cryst.

Growth 62 (1983) 642), thermal filament method (S.

Mhtsumoto, Y., 5lato, M.
Khmo hnd N.

5etalGa: Jor, J, Appl, P
hys, 21 (1982) L183), RF thermal plasma method (S9M'atsumoto, M.

Hino knd T, Kotfay'ashi:
Appl, Phys, Lett51 (1987)
A vapor phase growth method such as 737) can be used.

The microwave plasma method will be explained below.

In the microwave plasma method, a mixed gas of a carbon-containing compound and hydrogen is supplied through a quartz tube into a microwave cavity to generate microwave plasma, and a diamond-like substance is deposited in the form of a film on the surface of a substrate placed in the plasma. This is a method of forming.

Examples of carbon-containing compounds used include linear or cyclic saturated hydrocarbons such as methane, ethane, propane, butane, pentane, octane, and cyclohexane; Unsaturated hydrocarbons containing double or triple bonds; monofluoromethane, difluoromethane, trifluoromethane, tetrafluoromethane, monochloromethane, dichloromethane, trichloromethane,
Tetrachloromethane, monofluorodichloromethane, monofluoroethane, trifluoroethane, tetrafluoroethane, pentafluoroethane, hexafluoroethane, dichloroethane, tetrachloroethane, hexachloroethane, difluorodichloroethane, trifluorotrichloroethane, monofluoropropane, trifluoropropane , pentafluoropropane, perfluoropropane, dichloropropane, tetrachloroethane, hexachloropropane, perchloropropane, difluorodichloropropane, tetrafluorodichloropropane, bromomethane, methylene bromide, bromoform, carbon tetrabromide, tetrabromoethane, pentabromoethane, methyl Short, short methane, monofluorobutane, trifluorobutane, tetrafluorobutane, octafluorobutane, difluorobutane, monofluoropentane, pentafluoropencune, octachloropencune, perchloropencune, trifluorotrichloropentane, tetrafluorobutane Hexane, nonachlorohexane, pentafluorotrichlorohexane, tetrafluorohebutane, hexafluorohebutane, trifluoropentachloroheptane, difluorooctane, pentafluorooctane, difluorotetrachlorooctane,
Halogenated alkanes such as monofluorononane, hexafluorononane, decachlorononane, heptafluorohexachlorononane, difluorodecane, pentafluorodecane, tetrachlorodecane, tetrafluorotetrachlorodecane, octadecachlorodecane; allylamine,
Methylamine, ethylamine, pyridine, pyrimidine,
Nitrogen-containing organic compounds such as purine, picoline, and acrylamide; Sulfur-containing organic compounds such as carbon disulfide, methyl mercaptan, and ethyl mercaptan; Alcohols such as methanol, ethanol, and propatool; Phenol compounds such as phenol and cresol; Formaldehyde,
Aldehyde compounds such as acetaldehyde; acetone,
Examples include ketone compounds such as methyl ethyl ketone; fatty acids such as formic acid, acetic acid, and propionic acid; and alkyl esters of these fatty acids such as methyl esters and ethylestenopebutyl esters. moreover,
Other examples of carbon-containing compounds include inorganic carbon-containing compounds such as -carbon oxide, carbon dioxide, diazomethane, and tricarbon dioxide.

Among these carbon-containing compounds, particularly preferred are organic compounds having 4 or less carbon atoms, such as methane, ethane, propane, butane, ethylene, propylene, butadiene, allylamine, methylamine, ethylamine,
Examples include carbon disulfide, methanol, ethanol, formaldehyde, acetaldehyde, methyl ethyl ketone, formic acid, and ethyl acetate.

The ratio of hydrogen and carbon-containing compound to be used is preferably 0.1 to 5 moles, and 0.2 to 2 moles of carbon-containing compound per 100 moles of hydrogen.
Mole is more preferred. If the proportion of carbon-containing compounds is too small, the growth rate of diamond-like substances tends to be slow;
On the other hand, if this ratio is too large, a diamond-like substance containing a large amount of amorphous carbon is likely to be produced.

The flow rate of hydrogen is 0.1 per 1001 reactor capacity.
A range of ~101/min is preferred.

Note that the hydrogen and the carbon-containing compound may be separately supplied to the reaction zone and mixed and subjected to microwave discharge, or may be supplied to the reaction zone as a pre-mixed gas mixture and subjected to microwave discharge. In either case, the hydrogen supplied,
Carbon-containing compounds or mixed gases include helium,
A rare gas such as argon or xenon may be mixed. There is no particular restriction on the ratio of rare gas, but it is 8 per 100 moles of hydrogen.
It is preferably 0 mol or less.

The pressure near the substrate when performing the microwave plasma method is 0.5 to 760 Torr, especially 1 to 200 Torr.
r is preferable, and the energy density of the excited plasma may be 3 = 200 W/c, preferably 6 to 80 W/c.
W/cm".

When performing the microwave plasma method, the substrate is heated by plasma, usually at a temperature of 200 to 800°C, but in order to generate a diamond-like material, the temperature is 700 to 900°C.
℃, and therefore it is preferable to supplementally heat the substrate as necessary. For such heating, methods such as infrared heating, heat conduction heating, and induction heating can be used, for example.

The average thickness of the diamond-like material layer obtained as described above is not particularly limited, but it is preferably 50- or more, especially 10011111, since high thermal conductivity can be obtained.
It is preferably at least 10 mm, and usually 10 mm or less.

〔Example〕

Examples of the present invention will be described below, but the present invention is not limited to these.

Example 1 Electrolytic copper powder with an average particle size of 3Jl111 had an average particle size of 0.0
Five scales of aluminum oxide fine powder are mixed at a volume fraction of 4%, and 1.5 kg of this mixed powder is made into a powder with a diameter of 9.5 kg.
It was placed in a dry pulverizer with a capacity of 51 mm along with 17 kg of M steel balls, and was pulverized at a rotation speed of 35° rpm in an argon gas atmosphere.
A time pulverization process was performed.

The thus obtained mixed fine powder of copper and aluminum oxide was rolled using a rolling mill with a roll diameter of 150 m under a roll load of 2.
It was rolled at 5 tons and at a rotational speed of 5 rpm to obtain a plate-shaped green compact with a width of 35 mm and a thickness of 500 mm. This plate-shaped powder compact is heated at 980°C for 1 hour in dry hydrogen gas to sinter it,
Next, 35% cold rolling was performed, followed by annealing at 800°C for 1 hour in dry hydrogen gas, and further 30% cold rolling to form a copper matrix with a thickness of approximately 200 mm, in which aluminum oxide was finely dispersed in the copper matrix. Obtain a scale dispersion strengthened alloy plate,
From this, the length is 10m and the width is 5fflI11. Thickness 200J
A board was prepared by cutting out a plate piece of II11.

As shown in FIG. 1, a gas supply section (not shown) is connected to one end of the quartz reaction tube 1, and an exhaust mechanism is connected to the other end, and a microwave guide is connected to extend across the reaction tube 1. Using a microwave plasma reactor equipped with a wave tube 2, the substrate P is placed in the microwave waveguide region of the wave guide 2 in the reaction tube 1, and a flow rate of methane gas is supplied from the gas supply section to the reaction tube 1. 1 cc (STP) / min and hydrogen gas at a flow rate of 100 cc (STP) / min,
Under the conditions of a pressure of 4Q Torr, and with the microwave power adjusted so that the substrate temperature was 800°C, a reaction was performed for 75 hours by applying microwave heating and a mixed plasma of methane and hydrogen using the microwave to the substrate P. , average thickness 50
A diamond-like material layer was formed on the surface of the substrate P to produce a heat sink.

This heat sink was placed in a constant temperature oven and subjected to a heat cycle test from 0 to 400 degrees Celsius, but no abnormalities such as peeling or cracking occurred in the diamond-like material layer even after 50 heat cycles. .

Example 2 As shown in FIG. 2, a gas supply section (not shown) was connected to one end of the quartz reaction tube 11, and an exhaust mechanism was connected to the other end, so that the gas supply section (not shown) was connected to the other end so as to extend across the reaction tube 11. Using a microwave plasma reactor in which a microwave waveguide 12 is provided and an induction heating area by a high frequency coil 13 is provided, the induction heating area by the high frequency coil 13 in the reaction tube 11 has a length of 10 m and a width. A substrate material M made of an aluminum-copper alloy containing aluminum at a volume fraction of 4% and having a thickness of 5aua and 200mm was placed, and oxygen gas was supplied to the reaction tube 11 from the gas supply section at a flow rate of 1cc<5TP)/min. While supplying the material, the substrate material M was heated to 800° C. by the high-frequency coil 13 under the condition of a pressure of 2 Torr and a power of 510° C.
Oxygen-containing plasma generated by microwaves of W is applied to the substrate material M for 2 hours, so that aluminum oxide is almost uniformly distributed in the copper matrix at a volume fraction of 7%.
A dispersion-strengthened alloy plate was manufactured.

A heat sink was manufactured in the same manner as in Example 1 except that this dispersion-strengthened alloy plate was used as the substrate P, by forming a diamond-like material layer with an average thickness of 50 mm on the surface of the substrate P.

This heat sink was subjected to the same heat cycle test as in Example 1, but no abnormality such as peeling or cracking occurred in the diamond-like material layer even after wiping it after 50 heat cycles.

Comparative Example 1 A similar aluminum-copper alloy plate used as the substrate material in Example 2 was used as the substrate P for internal oxidation, and a diamond-like material layer was formed in the same manner as in Example 2. , peeling and cracking occurred in the diamond-like material layer immediately after formation.

Example 3 A substrate material M made of a titanium-copper alloy containing titanium with a volume fraction of 2% and having a length of 10 mm, a width of 5 cm, and a thickness of 200 ribs was subjected to the internal oxidation method in the same manner as in Example 2, and was dispersion strengthened. A diamond-like material layer having an average thickness of 50 μs was formed on the surface of the substrate P in the same manner as in Example 1 except that a type alloy plate was manufactured and this was used as the substrate P, and a heat sink was manufactured.

This heat sink was subjected to the same heat cycle test as in Example 1, but no abnormalities such as peeling or cracking occurred in the diamond-like material layer even after 50 heat cycles.

Example 4 A substrate material M made of a silicon-copper alloy containing 2.5% silicon at a volume fraction of 10 mm in length, 5 seconds in width, and 200 mm in thickness was subjected to the internal oxidation method in the same manner as in Example 2. Offer,
A dispersion-strengthened alloy plate was manufactured, and in the same manner as in Example 1 except that this was used as the substrate P, a diamond-like material layer with an average thickness of 50 μs was formed on the surface of the substrate P, and a heat sink was manufactured.

This heat sink was subjected to the same heat cycle test as in Example 1, but no abnormalities such as peeling or cracking occurred in the diamond-like material layer even after 50 heat cycles.

Example 5 A substrate material M consisting of an aluminum formulation containing 2% aluminum by volume fraction was prepared at a temperature of 90°C.
Subjected to the same internal oxidation method as in Example 2 except that the temperature was 0°C,
A dispersion strengthened alloy plate was manufactured.

The volume fraction of aluminum oxide in the surface portion of this dispersion-strengthened alloy plate was 3%, and the volume fraction at a depth of 1100 u from the surface inside the thickness direction was 1.7%.

Except for using this dispersion-strengthened alloy plate as the substrate P, the process was carried out in exactly the same manner as in Example 1, and the surface of the substrate P was coated with an average thickness of 50 μm.
A heat sink was manufactured by forming a diamond-like material layer of s.

This heat sink was subjected to the same heat cycle test as in Example 1, but no abnormalities such as peeling or cracking occurred in the diamond-like material layer even after 50 heat cycles.

Example 6 The formation time of the diamond-like material layer in Example 2 was changed to 1
A heat sink was manufactured in the same manner as in Example 2, except that a diamond-like material layer with an average thickness of 100 A was formed for 5 hours.

This heat sink was subjected to the same heat cycle test as in Example 1, but no abnormalities such as peeling or cracking occurred in the diamond-like material layer even after 50 heat cycles.

〔Effect of the invention〕

As described above, the heat sink of the present invention has a diamond-like material layer formed on a substrate made of a dispersion-strengthened alloy made of copper or a copper alloy in which metal oxide particles are dispersed. Even after a thermal cycle history, high adhesion between the substrate and the diamond-like material layer is obtained, and the overall thermal conductivity is high. Therefore, it is extremely useful as a heat sink for devices such as semiconductor lasers, IC packages, hybrid ICs, and Peltier elements.

[Brief explanation of the drawing]

FIG. 1 is an explanatory sectional view showing the configuration of an example of a microwave plasma reaction device, and FIG. 2 is an explanatory sectional view showing the configuration of an example of the plasma reaction device. 1... Reaction tube 2... Microwave waveguide P
... Substrate 11 ... Reaction tube 12 ... Microwave waveguide

Claims (1)

[Claims] 1) A heat sink comprising a substrate made of a dispersion-strengthened alloy in which metal oxide particles are dispersed in copper or a copper alloy, and a diamond-like material layer formed on the substrate.