JPH04132687A - Method for synthesizing diamond single crystal film - Google Patents

Abstract

PURPOSE:To obtain good films having various sizes by employing the single crystal of Ni, Co or Ni-Co alloy mixed with Fe, Cu, Cr, etc., in a prescribed ratio as a substrate when the diamond single crystal film is formed by a chemical gaseous phase method. CONSTITUTION:A substrate comprising a Ni single crystal, Co single crystal or Ni-Co alloy single crystal is prepared. The Ni single crystal is preferably mixed with one or more metals selected from <=50% of Fe, <=50% of Cu, 12% of Cr, <=10% of Mn, <=10% of Pt, <=10% of Pd, <=7% of Au and <=7% of Ag. The Co single crystal is preferably mixed with one or more metals selected from <=40% of Fe, <=40% of Cu, <=15% of Cr, <=10% of Mn, <=8% of Pt, <=8% of Pd, <=5% of Au and <=5% of Ag. A single crystal of diamond is formed on the substrate of the single crystal by a chemical phase method.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a method for synthesizing a diamond single crystal film.

(Prior art and problems to be solved) Due to its excellent properties, diamond is not only used as a hard material.
It is expected to be applied as a highly functional material such as electronic materials and luminescent materials. One of the fundamental technologies for electronic devices that is currently in practical use is the synthesis technology of single-crystal films with high crystallinity and controlled impurities. In order for diamond to be put to practical use as a highly functional material, it is necessary to establish a synthesis technology for high-quality single crystal films, just as with other materials.

Currently, high-pressure methods and chemical vapor phase methods (CVD methods) are known as diamond synthesis methods.

There are two types of high-pressure methods: the static high-pressure method, which uses a press to maintain high pressure and high temperature for a long time, and the dynamic high-pressure method (shock compression method), which uses explosives to instantaneously generate high pressure and high temperature. be. High-quality crystals are produced using a method (catalytic (method). However, this method cannot be applied to large single crystals, sintered bodies (
It is used for the synthesis of multi-nodular bodies) and is not suitable for the synthesis of thin films.

On the other hand, different chemical vapor phase methods are known, such as a thermal filament method, a microwave plasma CVD method, a high frequency plasma CVD method, a direct current plasma CVD method, and a combustion method. Since the chemical vapor phase method can synthesize diamond films on various substrates and is advantageous in controlling impurities, it is expected that it can be used to synthesize diamond for semiconductor materials, various electronic materials, and luminescent materials. The crystallinity of the diamond produced in any chemical vapor phase method strongly depends on the synthesis conditions (particularly the composition of the raw material gas and the substrate temperature), and the crystals produced usually have a higher concentration than natural diamond or high-pressure synthetic diamond. It is known to have some defects. Recently, by controlling these conditions, Ua, which is known as a high-purity type of natural diamond, has been developed.
It has been shown that high-quality diamond single crystals that exhibit properties close to those of regular diamonds can be synthesized. However, it has become clear that even under such appropriate conditions, polycrystalline films have a high concentration of defects.

Currently, diamond films synthesized on various substrates by chemical vapor deposition are polycrystalline, and polycrystalline films not only have a high defect concentration as mentioned above, but also have distortions.
It has become clear that crystallinity is inferior to that of single crystals, such as the fact that no interband luminescence is observed, and that there is an adverse effect on luminescent properties.

From this, it is easy to predict that there will be major restrictions on applications such as electronic materials and light-emitting materials that require high crystallinity. Further, inconveniences arise when synthesizing semiconductors. Diborane (B2HJ) containing boron in the raw material gas
By adding gas, a p-type semiconductor diamond doped with boron can be synthesized. in this case,
It is known that even with the same diborane concentration, boron is incorporated depending on the crystal plane and the concentration changes. The planes that appear in the vapor phase method are usually (111) or (100) planes, but in polycrystalline films, crystal grains with these two planes are arranged in a disordered manner, resulting in non-uniformity in the boronic concentration. arise. This causes non-uniformity in electrical conductivity, mobility, etc. The size of crystal grains is usually several microns, and although this non-uniformity can be ignored in devices with a size of several millimeters such as thermistors, it can be ignored in devices with submicron structures such as transistors and integrated circuits. Crystal films cannot be used.

Furthermore, it is well known that the mobility of silicon is greatly reduced compared to single crystal due to the presence of strain and grain boundaries, and this point is a decisive obstacle in creating high-speed devices.

As described above, polycrystalline films are not suitable for use as high-performance electronic materials or light-emitting materials, and therefore there is currently a need to establish a synthesis technique for single-crystalline films.

Against this background, there has been a desire to develop a technique for synthesizing single crystal films (epitaxial growth technique) using chemical vapor deposition, but there have been few success stories.

The best known is On the Diamond! This is Hayashi crystalline film synthesis, and because it grows with the same structure, it is also called homoepitaxial growth.

The size of the film is determined by the size of the diamond single crystal used as the substrate.

A typical example of growth on a different substrate is cubic boron nitride (cBN). It has the same crystal structure as diamond, and its lattice constant is extremely similar to that of diamond (
aT3N is 1.3% larger). There are reports from several different research institutions, c B N
Epitaxial growth at −J= is considered reliable. However, like diamond, cBN is a high-pressure stable phase and is currently synthesized by a high-pressure method. Synthesis of large single crystals is said to be more difficult than in the case of diamond substrates, and the possibility of mass production of high-quality crystals of 2 to 3 mm or more is extremely low.

For this reason, epitaxial growth of cBN on a substrate is not expected to have much practical value.

Further, a patent has been proposed for synthesizing a single crystal film using a silicon carbide (SiC) single crystal as a substrate. Although the synthesis of carbide pulley crystals does not require the same advanced technology as diamond and boron nitride, the difference in lattice constant from diamond is large (approximately 20%), so it is difficult to synthesize epitaxially grown diamond films. The strain may become extremely large, or dislocations may occur at a high density to alleviate the strain. Dislocations are a type of defect and are expected to have an adverse effect on the properties of the material.

Furthermore, it is difficult to synthesize a high-quality SjC single crystal with a size of several cm or more using normal synthesis methods, and it is necessary to use epitaxial growth technology using silicon as a substrate.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for economically synthesizing diamond single crystals of various sizes by eliminating the drawbacks of the prior art described above.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present inventors have conducted various studies on materials for substrates in chemical vapor deposition methods, and have hereby accomplished the present invention.

That is, in the present invention, when obtaining a diamond-containing film on a substrate by a chemical vapor phase method, the substrate is a nickel single crystal, Kobal 1~! , for crystal or nickel coating 1~
The gist of this invention is a method for synthesizing a diamond single crystal film, which is characterized by using an alloy single crystal.

The present invention will be explained in more detail below.

(Function) The substrate used in the present invention is a nickel or nickel alloy single crystal, a cobalt or nickel alloy single crystal, or a nickel-cobalt alloy single crystal.

These single crystals or single crystal films can be synthesized by conventional techniques such as a zone melt method, a pulling method, a Bridgman method, a vapor deposition method, and a vapor phase method.

Furthermore, there is no particular difficulty in synthesizing single crystals or single crystal films with a size of several cm or more, and this method is advantageous for producing high-performance devices.

As described above, the present invention is far more advantageous in terms of size and economy than technologies using diamond or cubic boron nitride as a substrate, and is far more advantageous than technologies using silicon carbide as a substrate. In addition to being economically advantageous, it is predicted that the synthesized single-crystalline film will have high crystallinity, and will have great significance in the practical application of high-performance materials using diamond, such as high-performance electronic materials and light-emitting materials. It is.

The basis of the method of the present invention is to use the aforementioned various single crystals as a substrate, and to epitaxially grow diamond thereon by a chemical vapor phase method.

As described above, the substrate may be a nickel or nickel alloy single crystal, a cobalt or nickel alloy single crystal, or a nickel-cobalt alloy single crystal. Examples of the component composition of these single crystals include the following.

In the case of nickel single crystal, nickel and iron = 50 ata+
% or less, copper: 50 atm or less, chromium: ], 2 atm
% or less, manganese: 10 atm % or less, platinum: 10 atm
m% or less, palladium: 1. Oatm% or less, gold near a
tm% or less and silver: one or two of 7 atm% or less
Single crystals with added seeds or more can be used.

In the case of cobalt single crystal, cobal 1~, iron: 40 atm
% or less, copper: 4. Oatm% or less, chromium: ]-5at
m% or less, manganese: 10 atm% or less, platinum: 8 atm
m% or less, palladium: 8 atm% or less, gold: 5 atm
% or less and silver: 5 atm % or less can be used.

In the case of nickel-cobalt single crystal, an alloy of Nj and Co in any proportion, or iron: 50 atm% or less, copper: 50 atm%
m% or less, chromium: 15 atm% or less, mangon: 1O
atm% or less, platinum: Oatm% or less, palladium: 1
0at+++% or less, gold: 7atm% or less and silver = 7
A single crystal containing one or more of atn% or less can be used.

Further, the nickel single crystal used for the substrate, the edge 1~ single crystal, and the nickel-cobalt single crystal are titanium.

m-crystal containing 1 stm% or less of any of molybdenum, tantalum, tungsten, silicon, and boron, or any combination of these elements? Total amount 1 stm%
Single crystals containing the following can also be used, and single crystals containing these elements and one or more of the above-mentioned iron, copper, chromium, manganese, platinum, palladium, gold, and silver can also be used. Available.

As mentioned above, the single crystal that becomes the substrate is a single crystal ingot synthesized by a crystal growth method such as a band melting method, a pulling method, or a Bridgman method, and then cut into the required plane direction, or by a vapor deposition method or a chemical vapor phase method. There are methods such as using a single crystal film epitaxially grown in a predetermined plane orientation by a method (for example, MOCVD method). Furthermore, a polycrystalline substrate can also be used to determine appropriate synthesis conditions. If the crystallites of the substrate are small, the polycrystalline substrate may be heat-treated at about 900°C in a reducing atmosphere (for example, in hydrogen plasma) to reduce the crystallite size to 1. It can be recrystallized to about mm. If such a polycrystalline substrate is used, it is possible to determine whether the synthesis conditions are suitable or not by observing the orientation of diamond within each crystallite.

As the chemical vapor phase method, any chemical vapor phase method known as a diamond synthesis method using carbon-containing gas as a raw material can be used. Thermal filament method, in which the source gas is activated with a tungsten wire heated to a high temperature of around 2000°C; the microwave plasma CVD method, in which the source gas is turned into plasma by electric discharge;
Typical examples include the high-frequency plasma CVD method, the DC arc plasma method, the high-frequency arc plasma method, and the combustion flame method, which uses the flame of a mixture of acetylene and oxygen in an appropriate ratio. (See Figures 4 to 4).

Next, we will use microwave plasma CV, which is one of the chemical vapor phase methods.
The synthesis method of the present invention will be explained in detail by taking method D as an example.

The reaction chamber (3) of the microwave plasma CVD method shown in Figure 1
) Place the nickel single crystal substrate on the sample support stand (7) provided approximately at the center of the sample support stand (7). When the substrate is cut out from a single crystal ingot, it is desirable to remove the disordered layer by acid treatment or the like. Furthermore, surface treatment to improve the nucleation density is also effective.

After evacuating the reaction chamber, a mixed gas of methane and hydrogen with a predetermined composition was introduced as a raw material gas, and after cleaning the reaction chamber for 10 to 20 minutes, the microwave was applied exclusively from the microwave oscillator (1) to start the reaction. The gas in the room is turned into plasma, and the power is adjusted to achieve a predetermined substrate temperature. At this time, if necessary, only hydrogen gas may be introduced first, and the substrate may be pretreated with hydrogen plasma. This is effective in removing organic matter, carbon, etc. attached to the surface. Hydrogen-
When the raw material is methane mixed gas, the total pressure is 40 Torr, the substrate is nickel, and the substrate temperature is 880°C), and the methane concentration is 0 and 9 vo 0% (hereinafter abbreviated as "%"), the diamond that is produced is similar to the substrate. Epitaxy relationship (
A single-crystal film was formed with a certain correspondence between the crystal orientation of the substrate and the crystal orientation of diamond. However, at methane concentrations of 1.0% or more, graphite was generated and no epitaxy was observed. In this intermediate region (0.9%
(Methane concentration: 1.0%) Satisfactory reproducibility was not obtained, with results varying depending on the part of the substrate.

Regarding the dependence of graphite formation on methane concentration, no significant difference was observed depending on the crystal plane, and the results for the cobalt substrate were almost the same. For comparison, an experiment using silicon or molybdenum as a substrate was conducted under the same conditions, and in this case, a polycrystalline film of relatively good quality was obtained even at 1.0%.

0°3vo of water vapor is added to the above methane-hydrogen system as a raw material gas.
When Q% was added, epitaxial growth was observed when methane was 1.8% or less, but graphite formation was observed when methane was 2.0% or more, and no single crystal film was formed.

Various combinations of raw material gases are known in chemical vapor phase synthesis, and any of them are effective in the present invention. C-H series, hydrocarbons represented by mixed gases of hydrocarbons and hydrogen such as methane, ethane, ethylene, and acetylene.
It may be a C-H-0 system such as hydrogen-steam (or oxygen), alcohol-hydrogen, carbon oxide-hydrogen, or acetylene-oxygen in the combustion flame method. In either case, the normally appropriate substrate temperature is within the range usually reported for vapor phase synthesis (approximately 400-1.100°C, preferably 50°C).
0-1000°C). According to detailed study, 8
It was shown that the epitaxy was more complete at higher temperatures of 50 to 950°C, and the nucleation density was relatively high at 750 to 900°C. For this reason, for example, nucleation is performed at 800°C in the initial stage of the reaction, and then at 950°C.
This operation is effective for obtaining a uniform and high quality single crystal film.

When growing diamond on nickel or cobalt as a substrate, it is important to suppress the formation of graphite. Due to the catalytic action of nickel and cobalt, graphite precipitation tends to be faster on these substrates than on many other substrates such as silicon and molybdenum. Therefore, for example, when the carbon concentration in the raw material gas is relatively high, even if diamonds are formed on other substrates, graphite is first formed on the substrate surface with nickel and Kobal 1-, and then diamonds are formed on the graphite. The phenomenon of generation is often observed. In this case, graphite usually has an epitaxy relationship with the substrate (the crystal orientation of graphite and the crystal orientation of the substrate have a certain correspondence relationship).
Therefore, even if diamonds formed on graphite have an epitaxial relationship with graphite, diamond does not have an epitaxial relationship with the substrate. Also.

From the observations so far, diamond 1 growing on graphite
No example has been found where ~ results in epitaxy. Therefore, even if the substrate and graphite are in an epitaxial relationship,
It is difficult to expect epitaxy between the substrate and diamond.

Under these circumstances, if a graphite layer is first formed on a nickel or cobalt substrate, the possibility of epitaxial growth is extremely low. This is thought to be the reason why diamond epitaxy has not been found so far in nickel and edge substrates. The formation of the graphite layer is controlled by the reaction conditions. Particularly important are the control of gas composition and substrate temperature (more precisely, substrate surface temperature).

Under conditions in which graphite is not produced at the initial stage of the reaction and only diamond is produced, the produced diamond has an epitaxial relationship with the substrate. The density of nucleation in Diamond 1 is usually 10 g/cm2 or less, and when a sample is observed with a scanning electron microscope at the early stage of the reaction, many crystal grains with uniform crystal orientation are observed. As the reaction time progresses, these particles grow and coalesce to form a single crystal film. Epitaxy and single crystallinity are confirmed by X-ray diffraction and electron diffraction.

Accurate determination of epitaxial growth is performed by X-ray diffraction or electron diffraction, but observation of the morphology of diamond particles using a scanning electron microscope or optical microscope at the initial stage of the reaction is simple and effective for determining the suitability of synthesis conditions. For example, when the substrate surface is (111), the particles are observed as equilateral triangles with uniform orientation, and when the substrate surface is (100), the particles are observed as squares with uniform orientation. Furthermore, observation of Raman spectra is effective in distinguishing between graphite and diamond, and accurate determination can be made by using them in combination with diffraction and morphological observation.

Several methods are used to measure the substrate temperature in current chemical vapor synthesis methods, depending on the synthesis method and the person performing the measurement. It is difficult to strictly define the appropriate conditions for crystal film synthesis. The most practical way to determine the appropriate conditions is to keep the substrate temperature constant (even if you cannot accurately determine the absolute value, you just need to confirm that it is constant), change the gas composition, and then compare the results as described above. This can be confirmed by morphology am, Raman spectrum measurement, etc.

The range of suitable conditions for forming diamond single crystal films on substrates of nickel, cobalt, and their alloys is silicon,
The general tendency is for the gas composition to be narrower than the conditions under which diamond films are formed on ordinary substrates such as molybdenum, tungsten, and quartz glass.

This is because, in the gas phase method, the conditions under which a few percent of graphite precipitates are generally recognized as the diamond formation region.
It is also related to the high precipitation rate of graphite on the nickel and cobalt surfaces. In the present invention, when the synthesis method, substrate temperature, and other conditions are constant, it is necessary to keep the carbon concentration in the raw material gas below a certain critical value and suppress the formation of graphite, so a lower concentration region than usual is appropriate. range.

In addition to the gas composition, it is desirable to prevent graphite from being generated not only on the surface of the substrate but also on other parts, such as the back side. This is achieved by also contacting the back side of the substrate with the plasma gas - it is also useful to make the temperature of the substrate as uniform as possible.

[Margin 1 below (Example) Next, examples of the present invention will be shown.

In the backyard ■ 99.99% purity, size 5 mm φ x 16011 IIl was placed on a substrate support dish in a quartz glass reaction tube with an inner diameter of 40 φ.
A nickel single crystal substrate with a (100) orientation was installed. After evacuating the reaction tube to 1O-4 Torr using a rotary pump and an oil diffusion pump, methane gas was released at 0.5v.
Hydrogen-methane mixed gas containing oQ% at 100mA/wi
The pressure inside the reaction tube was set to 40 Torr.

Next, microwaves were applied from outside the reaction tube to the location where the substrate was installed in a direction perpendicular to the reaction chamber to generate plasma.

After the plasma was turned on, the microwave input power was adjusted so that the substrate temperature was 880°C. The microwave input power at this time was 380W. The substrate temperature was measured from above the reaction tube using a radiation thermometer.

When synthesis was carried out for 2 hours under the above conditions, a granular material with uniform crystallographic orientation was precipitated. Electron diffraction and Raman spectroscopy confirmed that this granular material was diamond. When the synthesis was carried out for another 10 hours under the same conditions, adjacent diamond grains were joined together to obtain a diamond single crystal film.

Husband 1, purity 99.99%, size 5mmφX1. ．． Ommt,
When synthesis was performed for 2 hours under the same conditions using the microwave plasma CVD method shown in Example 1 using a nickel single crystal substrate with a (111) orientation, a granular material with uniform crystallographic orientation was precipitated. .

This granular material was confirmed to be diamond by X-ray diffraction and Raman spectroscopy. 10 more under similar conditions
When time-synthesis was performed, adjacent granular diamonds joined together to form a diamond single crystal film.

Lost 1 milky purity 99.99%, size 5III1φX1. Om
mt, using a cobalt single crystal substrate with (100) orientation,
By the microwave plasma CVD method shown in Example 1,
Using a hydrogen-methane mixed gas, the substrate temperature was 900°C, the methane gas concentration Q was 5%, and the tube pressure was 4-OT.

rr, total gas flow rate] 00 +n Q, / ml-n
When synthesis was carried out for 12 hours under the following conditions, diamond 1 to (11) crystalline films were obtained on a cobalt single crystal substrate.

Example-1- Purity 99.99%, size 5mmφX ], , Om
mt, using a nickel single crystal substrate with a (1,00) orientation, by the microwave plasma CVD method shown in Example 1, using a hydrogen-carbon oxide mixed gas, and at a substrate temperature of 9.
00°C1-carbon oxide gas concentration 2.0%, pipe pressure 4-
OT orr, total gas flow rate 100m+Q/1Ilin
When synthesis was carried out for 7 hours under the following conditions, a diamond single crystal film was obtained on a nickel single crystal substrate.

Loss - Example 1 Purity 99.99%, size 5m1IIφX J, O
vIll, using a nickel single crystal substrate with a (1,00) orientation, by the microwave plasma CVD method shown in Example 1, using a hydrogen-methane-steam mixed gas, with a substrate temperature of 880°C and a methane gas concentration of 1.8. %, water vapor concentration 0.5
%, pipe pressure 40 Torr, total gas flow rate 100+nρ/
When synthesis was carried out for 7 hours under conditions of min., a diamond single crystal film was obtained on a nickel single crystal substrate.

Fuba Mastan purity 99.99%, size 5ml 11φX 1, O
Using a nickel-65-cobalt-20-copper-15 alloy (ATM ratio) single-crystal substrate with +nmt, orientation (], OO) plane, hydrogen-methane-mixed gas was used by the microwave plasma CVD method shown in "Example". When synthesis was carried out for 12 hours under the conditions of a substrate temperature of 860°C, a methane gas concentration of 0.5%, a tube pressure of 4.0'rorr, and a total gas flow rate of 100 mQ/min, a diamond single crystal film was obtained on an alloy single crystal substrate. Ta.

5mmφ x 1.5mm purity 99.99% on a substrate support dish in a quartz glass reaction tube with an inner diameter of 40mmφ. On++n
A nickel single crystal substrate with a (1,00) orientation was installed. After evacuating the reaction tube to 10-” Torr using a rotary pump and an oil diffusion pump, methane gas was released at 0.5 V.
The substrate was heated in an electric furnace while flowing a hydrogen-methane mixed gas containing oQ% from one side of the reaction tube. Furthermore, electricity was applied to the substrate "on the other hand" and the tungsten filament installed at 0 mm, and heated to 2100"C.

When synthesis was carried out for 12 hours under the conditions of a substrate temperature of 880°C, a tube pressure of 50 Torr, and a total gas flow rate of 00 mff/min, diamond 1 was deposited on a nickel single crystal substrate.
~A single crystal film was obtained.

99.99% purity, size 5ml 1φX1. , Omm
t, using a cobalt single crystal substrate with a (1,00) orientation,
By the hot filament CVD method shown in Example 7, using hydrogen-ethyl alcohol mixed gas, the substrate temperature was 000°C.
, ethyl alcohol concentration 1.0%, pipe pressure 50 To
When the synthesis was carried out for 10 hours under the conditions of a total gas flow rate of 100IIIQ/min, a cobalt single crystal substrate was obtained.
Second, a diamond single crystal film was obtained.

Nickel 50-Cobalt 50 alloy (a
tm ratio) Using a single crystal substrate, a bias voltage of +80 V was applied to the substrate in a dish by the hot filament CVD method shown in Example 7. Using hydrogen-methane mixed gas, substrate temperature 8
50°C, methane gas concentration 0°5%, pipe pressure 50 T
Synthesis was carried out for 8 hours under conditions of a total gas flow rate of 100 mQ/win, and a diamond single crystal film was obtained on the alloy single crystal substrate.

Argon 50 + Hydrogen 10 A /
mjn is flowed from the top of the torch, and methane 0 is used as the raw material gas.
．． Plasma generating gas was added at 3Q/min. 4. Install a high frequency induction coil around the reaction tube. Arc plasma was generated by applying a high frequency of MHz. A water-cooled substrate support is installed at the plasma tip, and a substrate with a purity of 99.99% and a size of 5 mmφX1. Ommt, direction (
nickel 50-cobalt 50 alloy (at
m ratio) A single crystal substrate was placed.

The input power was 40 kW, the gas pressure was atmospheric pressure, and the substrate temperature was adjusted to 880'C by cooling the substrate support.

When synthesis was carried out for 15 minutes under the conditions described above, a diamond single crystal film was obtained on a nickel ζ crystal substrate-I.

Large Dust Reigetsu-V Using the high-frequency arc plasma CvD method shown in Example 10, the substrate was made into a substrate under the same conditions with a purity of 99.99% and a size of 5.
mmφX1. Ommt, 1 for edge of direction (1-00) plane
~ After 15 minutes of synthesis using a single crystal substrate,
A diamond single crystal film was obtained on a cobalt single crystal substrate.

Intuition 1ii112- Acetylene gas and oxygen gas were flowed into the melt-cutting gas burner at a rate of 1 and 5 Q/min, respectively, so that the length of the combustion flame was approximately 30 mm. A water-cooled substrate support is placed in this inner flame, and this has a purity of 99.99% and a size of 5 mmφ.
X1. A nickel single crystal substrate with a (1-00) orientation was fixed. The substrate was placed 5 mm from the tip of the burner.

The temperature of the substrate was 880°C by cooling, and the temperature was 200°C in the air.
When synthesis was carried out for minutes, a diamond single crystal film was obtained on a nickel (1) crystal substrate.

A nickel 50-iron 50 alloy (ATM ratio) substrate with a size of 1 Omm x 1 Omm x 0.5 mm that was heat-treated in a hydrogen furnace at a temperature of 900°C and a pressure of 1 atm for 30 minutes was used as shown in Example 1. Synthesis was performed for 10 hours using a hydrogen-methane mixed gas using a microwave plasma CVD method under the conditions of a substrate temperature of 880'C, a methane gas concentration of 0.5%, a tube pressure of 40 Torr, and a total gas flow rate of 100 ml/min. However, a diamond single crystal film was obtained on each crystallite of the substrate.

Loss of embrittlement - Heat treated in a Mikitosho hydrogen furnace at a temperature of 900°C and a pressure of 1 atm for 30 minutes. Size: 1 OmmX 1. OmmX 0.5mm
Using a nickel 50-copper 50 alloy (fltlll ratio) substrate of
, methane gas concentration 0.5%, pipe pressure 40T orr,
When the synthesis was carried out for 10 hours under the condition of a total gas flow rate of 100 mQ/mjn, a diamond single crystal film was obtained on each crystallite of the substrate.

Heat treated for 30 minutes at 900℃ and atmospheric pressure in a hydrogen furnace on board the ship. OmmX ], OmmX 0.5m
Using a nickel 88-chromium 12 alloy (ATM ratio) substrate of m, the substrate temperature was 880°C using a hydrogen-methane mixed gas by the microwave plasma CVD method shown in Example 1.
, methane gas concentration 0.5%, pipe pressure 4,0 Tor or
Synthesis was carried out for 10 hours under the conditions of r, total gas flow rate of 100 mQ, /mjn, and a diamond single crystal film was obtained on each crystallite of the substrate.

Example 1-6 Heat treated in a hydrogen furnace at a temperature of 900'' C1 pressure of 1 atm for 30 minutes Size 1 OmmX I OmmX 0.5mm
Using a nickel 90-manganese 10 alloy (a+monocarbon) substrate of
, methane gas concentration 0.5%, pipe pressure 40 Torr, total gas flow rate 1. When synthesis was carried out for 10 hours under the conditions of OO+nfL/mjn, a diamond single crystal film was obtained on each crystallite of the substrate.

Using a nickel 90-platinum 10 alloy (ATM ratio) substrate with a size of 1 Omm x 1 Omm x 0.5 mm that was heat-treated for 30 minutes at a temperature of 900°C and a pressure of 1 atmosphere in an Odori Uni-hydrogen furnace,
By the microwave plasma CVD method shown in Example 1, using a hydrogen-methane mixed gas, the substrate temperature was 880°C, the methane gas concentration was 0.5%, the tube pressure was 40 T orr, and the total gas flow rate was 100 mQ/min. When time synthesis was performed, a diamond single crystal film was obtained on each crystal ball of the substrate.

A nickel 90-palladium 10 alloy (ATM ratio) substrate of 0 mm x 10 mm x 0.5 mm was heat-treated in a hydrogen furnace at a temperature of 900 cm and a pressure of 1 atm for 30 minutes. Synthesis was carried out using a hydrogen-methane mixed gas by wave plasma CVD method for 10 hours under the conditions of a substrate temperature of 880°C, methane gas concentration of 0.5%, tube pressure/JOTorr, and total waste flow t of 100 mQ/min. A diamond single crystal film was obtained on each crystallite-L of the substrate.

Included U rice - Example - ↓ - 廄 - Conducted using a nickel 93-gold 7 alloy (ATM ratio) substrate of size 10 mm By the microwave plasma CVD method shown in Example 1, a hydrogen-methane mixed gas was used, the substrate temperature was 880°C, the methane gas concentration was 0.5%, the tube pressure was 401'', orr, and the total gas flow rate was 1.
When synthesis was carried out for 10 hours under the condition of 00 mQ/min, a diamond single crystal film was obtained on each crystallite of the substrate.

(Example -?-p Heat treated in a hydrogen furnace at a temperature of 900°C and a pressure of 1 atm for 30 minutes. Size J, Omm
Using a nickel 93-silver 7 alloy (ATM ratio) substrate of n,
By the microwave plasma CVD method shown in Example 1,
When synthesis was carried out for 10 hours using a hydrogen-methane mixed gas under the conditions of a substrate temperature of 880°C, a methane gas concentration of 0.5%, a tube pressure of 40 Torr, and a total gas flow rate of 100 mQ/mjn, each crystallite on the substrate A diamond single crystal film was obtained.

Example 21 A cobalt 60-iron 40 alloy (ATM ratio) substrate with a size of 10 mm x 1 Omm x 0.5 mm that was heat-treated in a hydrogen furnace at a temperature of 900°C and a pressure of 1 atm for 30 minutes was used to conduct the microwave treatment shown in Example 1. Synthesis was carried out for 10 hours using a hydrogen-methane mixed gas using a plasma CVD method under the conditions of a substrate temperature of 880°C, a methane gas concentration of 0.5%, a tube pressure of 40 Torr, and a total gas flow rate of 100 mQ/ll1in. A diamond single crystal film was obtained on the second crystallite.

Example 2 In a hydrogen furnace at a temperature of 900°C and 1 pressure. Heat treated at atmospheric pressure for 30 minutes Size: 1 Omm x 1 Omm x 0.5m
Using a cobalt 60-copper 40 alloy (ATM ratio) substrate of m, the microwave plasma CVD method shown in Example 1 was performed using a hydrogen-methane mixed residue, the substrate temperature was 880°C, the methane gas concentration was 0.5%, and the inside of the tube was heated. Synthesis was carried out for 10 hours under the conditions of a pressure of 40 Torr and a total gas flow of 3110 Q mQ, / mj, n, and a diamond single crystal film was obtained on the substrate.

Example 2-W Heat treated in a hydrogen furnace at a temperature of 900°C and a pressure of 1 atm for 30 minutes], OmmX 1-QmmX 0.5m
Using a cobalt 85-chromium 15 alloy (ATM ratio) substrate of m, the microwave plasma CVD method shown in Example 1 was performed using a hydrogen-methane mixed gas, and the substrate temperature was 880.
°C, methane gas concentration 0.5%, pipe pressure 4.0 Torr
When the synthesis was carried out for 10 hours under the condition of a total gas flow rate of 100 mQ/min, a diamond single crystal film was obtained on each crystallite-L of the substrate.

Shishikireho-λ-4 Heat treated in a hydrogen furnace at a temperature of 900°C and a pressure of 1 atm for 30 minutes], OmmXlommXo, 5mm cobalt 90-manganese 10 alloy (at, m ratio) substrate, Example] Synthesis was carried out for 10 hours using a hydrogen-methane mixed gas using the microwave plasma CVD method shown in , under the conditions of a substrate temperature of 880°C, a methane gas concentration of 0.5%, an internal pressure of 40 Torr, and a total gas flow rate of 100n+Q/mjn. As a result, a diamond single crystal film was obtained on the substrate.

A cobalt 92-platinum 8 alloy (ATM ratio) substrate with a size of 10 mm x 10 mm x 10.5 mm that was heat-treated in an alternating hydrogen furnace at a temperature of 900°C and a pressure of 1 atm for 30 minutes was used, and the microwave plasma shown in Example 1 was used. Hydrogen-
Using methane mixed gas, substrate temperature 880°C, methane gas concentration 0.5%, pipe pressure 40T orr, total gas flow rate 1
When the synthesis was carried out for 10 hours under the condition of 00 mQ /mjn, a diamond single crystal film was obtained on the substrate.

A Cobalt 92-Parasol 48 alloy (ATM ratio) substrate with dimensions Omm x 10mm x 0.5mm was heat treated in a hydrogen furnace for 30 minutes at a temperature of 900'C and a pressure of 1 atm, as shown in Example 1. By microwave plasma CvD method, using hydrogen-methane mixed gas, substrate temperature is 880℃,
Synthesis was carried out for 10 hours under the conditions of methane gas concentration of 0.5%, tube internal pressure of 40 Torr, and total gas flow rate of 100 m (1/mjn), and a diamond single crystal film was obtained on each crystallite of the substrate.

Heat treated in a hydrogen furnace for 30 minutes at a temperature of 900°C and a pressure of 5 mm, using a cobalt 95-gold 5 alloy (ATM ratio) substrate with a size of OmmXlommXo and 5 mm, the micro Using the wave plasma CVD method, a hydrogen-methane mixed gas was used, the substrate temperature was 880°C, the methane gas concentration was 0.5%, the tube pressure was 40 Torr, and the total gas flow rate was 100.
When synthesis was carried out for 10 hours under the conditions of mQ/mjn, a diamond single crystal film was obtained on the substrate.

Heat treated in a hydrogen furnace for 30 minutes at a temperature of 900℃ and a pressure of 1 atm], OmmX I OmmX 0.5mm
Using a 1-95-silver 5 alloy (ATM ratio) substrate for the edge of
By the microwave plasma CVD method shown in Example 1,
Using hydrogen-methane mixed gas, substrate temperature 880°C, methane gas concentration 0.5%, pipe pressure 40T orr, total gas flow rate 100m11! When the synthesis was carried out for 10 hours under the condition of /min, a diamond single crystal film was obtained on the substrate.

1ii□11;su□□;≧shi■ 1 Size with atm% of titanium added]OmmX]0
Nickel of mm x 0.5 mm was heated in a hydrogen furnace at a temperature of 900°C.
, and a pressure of j atmospheres for 30 minutes. By the microwave plasma CVD method shown in Example 1 using this as a substrate,
Synthesis was carried out for 10 hours using a hydrogen-methane mixed gas under the conditions of a substrate temperature of 880°C, a methane gas concentration of 0.5%, an internal pressure of 40 Torr, and a total gas flow rate of 100 mQ/min. A diamond single crystal film was obtained.

Size 10nvX with 1atm% molybdenum added
1 Omm x 0.5 mm of nickel was heat treated in a hydrogen furnace at a temperature of 900° C. and a pressure of 1 atmosphere for 30 minutes. Using this as a substrate, the microwave plasma CVD method shown in Example 1 was carried out using hydrogen-methane mixed gas, and the substrate temperature was 880.
℃, methane gas concentration 0.5%, pipe pressure 4. QT
orr, 10 under the condition of total gas flow rate 100 mQ/min
When time synthesis was performed, a diamond single crystal film was obtained on the substrate.

Arrow stream side, pj.

1. Size 10Illll with atm% tantalum added
I+x] OmmX 0.5 mm of nickel was heat-treated in a hydrogen furnace at a temperature of 900° C. and a pressure of ]atmosphere for 30 minutes. Microwave plasma C shown in Example 1 using this as a substrate
V D 7A, using hydrogen-methane mixed gas, substrate temperature 880°C, methane gas concentration 0.5%, tube pressure 4
Synthesis was carried out for 10 hours under the conditions of 0 Torr and a total gas flow rate of 100 mQ/mjn, and a diamond single crystal film was obtained on each crystallite of the substrate.

Husband I - Shadow λ] Size 10nv with atm% tungsten added
+X 1. OmmX 0 , 5 mm of nickel was heat treated in a hydrogen furnace at a temperature of 900° C. and a pressure of 1 atmosphere for 30 minutes.

Using this as a substrate, the microwave plasma CVD method shown in Example 1 was performed using a hydrogen-methane mixed gas at a substrate temperature of 880°C, a methane gas concentration of 0.5%, and a tube pressure of 40T.
Synthesis was carried out for 10 hours under conditions of a total gas flow rate of 100 m1+/min, and a diamond single crystal film was obtained on the substrate.

[Size 10n+llll with 15tIN% silicon added
Nickel measuring 10 mm x 0.5 mm was heated in a hydrogen furnace at a temperature of 9
Heat treatment was performed at 00° C. and 1 atm pressure for 30 minutes. This was used as a substrate by the microwave plasma CVD method shown in Example 1, using hydrogen-methane mixed gas, and at a substrate temperature of 880°.
C, methane gas concentration 0.5%, pipe pressure 40 Torr,
10 under the condition of total gas flow rate 1001IIQ/ll1jn
When time synthesis was performed, a diamond single crystal film was obtained on the substrate.

Disappointed ± 1stm% of boron added size 10mm x] 0
Nickel of mm x 0.5 mm was heated in a hydrogen furnace at a temperature of 900°C.
, and heat treated at a pressure of 1 atm for 30 minutes. By the microwave plasma CVD method shown in Example 1 using this as a substrate,
Using a hydrogen-methane mixed gas, the substrate temperature was 880°C, the methane gas concentration was 0.5%, and the tube pressure was 4. When the synthesis was carried out for 10 hours under the conditions of Q Torr, total gas flow M]OOmn/min, a diamond 1 to () 1 crystalline film was obtained on the substrate winter crystals.

Practical application low-4-view-''al;m% titanium added size 1.0mmX1
Cobalt of 0 mm x 0.5 nv was heated to a temperature of 900 in a hydrogen furnace.
Heat treatment was carried out for 30 minutes at 1°C and 1"atm. Using this as a substrate, the microwave plasma CVD method shown in Example 1 was performed using a hydrogen-methane mixed gas at a substrate temperature of 880°C.
When synthesis was carried out for 10 hours under the conditions of methane gas concentration Q of 5%, tube pressure of 40 Torr, and total gas flow rate of 100 mQ/mjn, diamond 11 was formed on the substrate winter crystallites.
．． A crystal film was obtained.

Fruit circulation ii Sutan 1 Size 10mmX with atm% molybdenum added
Kobal 1~ of 10 mm x 0.5 mm was heat treated in a hydrogen furnace at a temperature of 900°C and a pressure of J atm for 30 minutes. Using this as a substrate, microwave plasma CVD was performed as shown in Example J.
By the method, using hydrogen-methane mixed gas, the substrate temperature was 88℃.
0°C, methane gas concentration 0.5%, pipe pressure 40 Tor
r, total gas flow rate 100mF, 10 under the conditions of /mjn
When time synthesis was performed, a diamond single crystal film was obtained on the substrate.

Size with added tantalum of 1 atm%], Omm
Cobalt of Xl 0 mm x 0.5 mm was heat treated in a hydrogen furnace at a temperature of 900° C. and a pressure of 1 atmosphere for 30 minutes. Microwave plasma CV shown in Example 1 using this as a substrate
By method D, using hydrogen-methane mixed gas, the substrate temperature is 8.
80℃, methane gas concentration 0.5%, pipe pressure 40 Torr
r, 1 under the condition of total gas flow rate 100mm/lll1n
When the synthesis was carried out for -0 hours, a diamond single crystal film was obtained on the substrate.

Size 10mm with added stm% tungsten
A Kobal 1 ~ x 10 mm x 0.5 mm was heat treated in a hydrogen furnace at a temperature of 900'C1 pressure of 1 atm for 30 minutes.

Using this as a substrate, the microwave plasma CVD method shown in Example 1 was carried out using a hydrogen-methane mixed gas, the substrate temperature was 880'C, the methane gas concentration was 0.5%, and the tube pressure was 4.
0 Torr, total gas flow f! : ]-00m Q, /m
When the synthesis was carried out for 10 hours under the condition of 100 nm, a single crystal film of 1 diamond was obtained on each crystallite-L of the substrate.

Kyoto Masu - Shadow 1 - Size 10 mm x 0 m with 1 at% silicon added
m x 0.5 mm of Kobal 1- in a hydrogen furnace at a temperature of 900°C.
, and heat treated at a pressure of 1 atm for 30 minutes. This was used as a substrate by the microwave plasma CVD method shown in Example 1, using a hydrogen-methane mixed gas, substrate temperature 880°C, methane gas concentration 0.5%, tube pressure 40 Torr, total gas flow rate "OOm 1+, / When the synthesis was carried out for 10 hours under conditions of min.
~A single crystal film was obtained.

Size: 10 mm x 10 m with 1 atm% of boron added
m x 10.5 mm of cobalt in a hydrogen furnace at a temperature of 900'
Heat treatment was performed at a C1 pressure of 1 atm for 30 minutes. Using this as a substrate, the microwave plasma CVD method shown in Example] was performed using a hydrogen-methane mixed gas at a substrate temperature of 880°C, a methane gas concentration of 0.5%, and a tube pressure of 4. Synthesis was carried out for 10 hours under the conditions of QTorr and a total gas flow rate of 100 mm 2 /min, and a diamond 1 (single crystal film) was obtained on the substrate.

Lost volume = 1, size 10mm 10m with atm% titanium added
mX10.5mm nickel 40-cobalt 40 copper 20
Alloy (ATM) ratio in a hydrogen furnace at a temperature of 900°C and a pressure of 1
Heat treatment was performed at atmospheric pressure for 30 minutes. Example 1 using this as a substrate
Using the microwave plasma CVD method shown in Figure 1, using a hydrogen-methane mixed gas, the substrate temperature was 880°C, the methane gas concentration was 0.5%, the tube pressure was 40 Torr, and the total gas flow rate was 100.
When the synthesis was carried out for 10 hours under the condition of mm 2 /min, a diamond single crystal film was obtained on the substrate.

(Effects of the Invention) As detailed above, according to the present invention, since a specific material is used as the substrate in the chemical vapor deposition method, a diamond single crystal film can be formed on the substrate, and moreover, it is economical. It is.

[Brief explanation of drawings]

The drawings all show embodiments of the present invention, and FIG. 1 is a schematic diagram of a method using plasma induced by mital waves, FIG. 2 is a schematic diagram of a method using heated filament 1-, and FIG. The figure is a schematic diagram of a method using plasma induced by high frequency, and FIG. 4 is a schematic diagram of a method using combustion flame. ]... Microwave oscillator, 2... Waveguide, 3 Reaction chamber,
4. Board, 5. Gas supply device, 6. Air supply material, 7
- Substrate support stand, 8... Electric furnace, 9 - Tanksten filament 1~. 10・High frequency induction coil, 11 Cooling water, 1
2 burner, 13... combustion flame.

Claims (5)

[Claims] (1) A method for synthesizing a diamond single crystal film, which comprises using a nickel single crystal, a cobalt single crystal, or a nickel-cobalt alloy single crystal as the substrate when obtaining the diamond single crystal film on a substrate by chemical vapor deposition. (2) The nickel single crystal used in the substrate contains nickel, iron: 50 atm% or less, copper: 50 atm% or less, and chromium:
12 atm% or less, manganese: 10 atm% or less, platinum: 10 atm% or less, palladium: 10 atm% or less,
1 of Gold: 7 atm% or less and Silver: 7 atm% or less
The method according to claim 1, wherein a species or two or more species are added. (3) The cobalt single crystal used for the substrate contains cobalt, iron: 40 atm% or less, copper: 40 atm% or less, and chromium:
15 atm% or less, manganese: 10 atm% or less, platinum: 8 atm% or less, palladium: 8 atm% or less, gold:
The method according to claim 1, wherein one or more of the following is added: 5 atm% or less and silver: 5 atm% or less. (4) The nickel-cobalt single crystal used for the substrate is iron:
50 atm% or less, copper: 50 atm% or less, chromium: 1
5 atm% or less, manganese: 10 atm% or less, platinum:
The method according to claim 1, wherein one or more of the following are added: 10 atm% or less, palladium: 10 atm% or less, gold: 7 atm% or less, and silver: 7 atm% or less. (5) The nickel single crystal, cobalt single crystal, and nickel-cobalt single crystal used for the substrate are titanium, molybdenum,
Claim 1, 2, 3, or 4, which is a single crystal containing tantalum, tungsten, silicon, or boron in a total amount of 1 atm% or less, or a single crystal containing any combination of these elements in a total amount of 1 atm% or less. The method described in.