JP2002115058A - Process for depositing graphite nanofiber thin film by thermal cvd process - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the adhesion between a metallic thin film undercoat layer and a substrate in the deposition of a graphite nanofiber thin film used for a carbon based electron emission source. SOLUTION: A substrate obtained by depositing the surface of a glass substrate or an Si substrate with a thin film of Fe, Co or an alloy containing at least one kind of those metals into prescribed patterns is placed in an evacuated vacuum chamber and is subjected to heat treatment in a vacuum, after that, a carbon-containing gas and gaseous hydrogen are introduced into the chamber, the pressure in the chamber is kept at about 1 atm., and graphite nanofiber is grown only on the pattern parts on the substrate by a thermal CVD process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming a graphite nanofiber thin film by a thermal CVD method, and more particularly, to a method of heat-treating a substrate on which a metal thin film is formed before growing the graphite nanofiber by a thermal CVD method. The present invention relates to a method for forming a thin film. This method can be used to fabricate an electroluminescent device used in place of a flat display (field emission display) or an electron tube of a CRT.

[0002]

2. Description of the Related Art Conventionally, a conical cathode tip (a tip made of W, Mo, Si or the like) is formed on an electrode substrate as a cold cathode source which is an electron emission source for emitting electrons without heating. Things have been suggested. In the case of this cathode chip, for example, an emitter manufactured using a Mo chip and used for a display is currently 100 V / μm.
It can only be driven by an electric field of m.

As described above, Si, Mo, and the like have been studied as cathode materials. In recent years, the use of carbon nanotubes as cathode materials has been studied. A carbon nanotube is a graphite fiber having a helical structure having a carbon 6-membered ring as a main structure, having a hollow cylindrical shape inside, and having an extremely fine, multi-layered structure in which cylinders are arranged concentrically. This carbon nanotube is superior to other metal materials in performances such as electron emission characteristics, heat resistance, and chemical stability. Carbon nanotubes are usually produced by an arc discharge method, a laser evaporation method, a plasma CVD method, or the like.

The present inventors have intensively studied and developed a cathode material having a high electron emission density and a low field electron emission performance. However, the cathode material was formed by a thermal CVD method using a carbon-containing gas and a hydrogen gas. In the process of forming a film, a graphite nanofiber having a structure which has not been reported was found, and since the graphite nanofiber has excellent electron emission characteristics, it was found on February 4, 2000 and March 28, 2000 that: See Japanese Patent Application 2000-28001
No. and 2000-89468. Unlike the carbon nanotubes, the graphite nanofiber is a solid in which a graphene sheet is cut into small pieces and stacked, and has, for example, a columnar structure in which crystals having a truncated cone shape are stacked. There is a through cavity at the center, which is hollow or filled with amorphous carbon. The obtained graphite nanofiber has a diameter of 10 nm to 600 nm.
Those having a diameter of 10 nm and a diameter of less than 10 nm have not been synthesized so far, and those having a diameter of more than 600 nm have poor electron emission performance. Such a graphite nanofiber is useful as a cathode material having excellent electron emission characteristics such as high electron emission characteristics and low field electron emission performance.

[0005]

However, when trying to use the above-mentioned conventional carbon nanotube as a cold cathode source (electron emission source), electron emission from the carbon nanotube occurs from its tip or from a defect. In addition, there is a problem that it cannot be applied as an electron emission source requiring a high current density, such as a CRT electron source.

The present inventors have found that it is difficult to efficiently form a graphite nanofiber thin film at a predetermined position on a substrate to be processed by the technique relating to the formation of a graphite nanofiber thin film by the thermal CVD method as described above. From this fact, a method was found in which a graphite nanofiber thin film could be selectively formed at a predetermined location.However, when this forming method was implemented, the distance between the metal thin film of the base layer for forming the graphite nanofiber thin film and the substrate was reduced Adhesion may be slightly poor, and the metal thin film may peel off from the substrate.

The present invention solves the above-mentioned problems, and forms a graphite nanofiber thin film that can serve as a carbon-based electron emission source as a cathode material that can achieve high electron emission density and low field electron emission performance. It is another object of the present invention to improve the adhesion between the metal thin film of the underlayer and the substrate.

[0008]

According to a method of forming a graphite nanofiber thin film of the present invention, a thin film of Fe, Co or an alloy containing at least one of these metals is formed in a predetermined pattern on a glass substrate or a Si substrate. A film forming method in which the formed substrate is used as a substrate to be processed, and a carbon nano-gas and a hydrogen gas are used by a thermal CVD method to grow graphite nanofibers uniformly only in a pattern portion on the substrate to be processed. Before performing the thermal CVD method, the substrate to be processed is subjected to a heat treatment under vacuum, whereby the adhesion of the metal thin film pattern portion to the substrate is improved.

Further, the method for forming a graphite nanofiber thin film of the present invention comprises the steps of:
e, Co, or a substrate on which a thin film of an alloy containing at least one of these metals is formed in a predetermined pattern is used as a substrate to be processed. Heating with a lamp, introducing a carbon-containing gas and a hydrogen gas into the vacuum chamber, maintaining the pressure in the vacuum chamber at approximately 1 atm. Is a film forming method for uniformly growing the substrate, wherein the substrate to be processed is subjected to a heat treatment under vacuum before the thermal CVD method is performed to improve the adhesion of the pattern portion to the substrate.

The temperature at which the heat treatment is performed is 400 ° C. or higher,
The temperature is preferably lower than the heat resistance temperature of the substrate. If the heat treatment temperature is lower than 400 ° C., the adhesion of the metal thin film pattern portion to the substrate will not be improved, and if the heat treatment temperature exceeds the heat resistant temperature of the substrate, the substrate will be deformed.

The mixing ratio of the carbon-containing gas and the hydrogen gas is, based on the volume, carbon-containing gas / hydrogen gas = 0.1 to 1
It is preferably 0. If the mixing ratio is less than 0.1, it is difficult to efficiently form the graphite nanofiber thin film, and if it exceeds 10, the carbon-containing gas concentration is too high to control the process of forming the graphite nanofiber thin film. There is a problem that is substantially difficult. The hydrogen gas is used for dilution and catalysis in a gas phase reaction.

The temperature for performing the thermal CVD method is 450 to
Preferably it is 650 ° C. If the temperature is lower than 450 ° C., the carbon-containing gas as a raw material gas is hardly decomposed, so that there is a problem that the growth rate of the graphite nanofiber becomes extremely slow and it is not economical. In addition, the growth rate increases as the temperature increases, but if it exceeds 650 ° C., there is a problem that it is substantially difficult to control the process of forming the graphite nanofiber thin film.

As the carbon-containing gas, for example, a carbon-containing gas such as carbon monoxide, carbon dioxide, or a lower hydrocarbon such as methane can be used, and carbon monoxide or carbon dioxide is preferable.

After the metal thin film is formed in a predetermined pattern and subjected to a heat treatment, the surface of the thin film is etched by a wet etching method or the like to roughen the surface state, and then a thermal CVD method is performed. It is preferred that the growth of graphite nanofibers be very good.

[0015]

According to the method of the present invention, a graphite nanofiber thin film is made of Fe, C
o, or a glass substrate or a Si substrate on which a metal thin film of an alloy containing at least one of these metals is formed in a predetermined pattern, first heat-treated under vacuum at a predetermined temperature, and then by a thermal CVD method, For example, using a carbon-containing gas such as carbon monoxide and carbon dioxide, and hydrogen gas,
It is manufactured by uniformly growing graphite nanofibers only at the metal thin film pattern at 50 to 650 ° C. The heat treatment under vacuum improves the adhesion between the pattern and the substrate.

The method of forming the metal thin film pattern on the substrate to be processed is not particularly limited.
It can be performed by forming and attaching a pattern to a predetermined location on the substrate under normal conditions using a method, an evaporation method (for example, an EB evaporation method), or the like. Alternatively, a substrate having the metal thin film pattern applied to a predetermined portion of the substrate surface by a photolithographic process performed by applying a known photosensitive resin liquid on the substrate surface, by a printing process, or by a plating process, etc. Then, after heat-treating this substrate under vacuum, graphite nanofibers may be uniformly grown and formed by thermal CVD at the place where the metal thin film has been applied as described above. The shape of the pattern is not particularly limited, and may be a straight line, a curve, a dotted line, or any other shape.

In the method of forming a graphite nanofiber thin film according to the present invention, first, a substrate holder on which a substrate to be processed having the above-described metal thin film pattern is mounted is placed in a vacuum chamber of a thermal CVD apparatus provided with an infrared lamp. And placed inside the chamber, usually 0.1 mm
Vacuum exhaust is performed until the pressure becomes about 0.01 Torr. Next, a plurality of infrared lamps provided to face the substrate to be processed are energized in the upper part of the vacuum chamber, and a heat treatment is performed in a vacuum at a temperature of 400 ° C. or more and a heat resistant temperature of the substrate for 1 to 30 minutes. Thereafter, a mixed gas of a carbon-containing gas and a hydrogen gas is introduced into the chamber at a predetermined volume ratio, preferably at a carbon-containing gas / hydrogen gas ratio of 0.1 to 10 to perform gas replacement. At this time, the substrate is heated using the infrared lamp, and preferably at a temperature of 450 ° C. to 650 ° C., the graphite nanofibers are grown uniformly only on the metal thin film pattern on the substrate, and the graphite nanofiber thin film is formed. To form The graphite nanofiber thus obtained has a diameter of about 10 to 100 nm. If the mixed gas is heated in advance before being introduced into the vacuum chamber, the temperature can be raised to the film forming temperature in a short time, and the film forming speed is adjusted by providing such a heating means. You can also.

As described above, before the thermal CVD method is performed, the substrate on which the metal thin film pattern is formed is heat-treated, whereby the adhesion between the pattern and the substrate is improved. The graphite nanofiber obtained in this way is
The field emission characteristics of the carbon-based electron emission source can be improved. In other words, it is possible to emit electrons at a sufficiently high current density at a voltage as low as that of a conventional carbon nanotube, so as to be used for a CRT electron source.

The thermal CVD apparatus used to carry out the method for forming a graphite nanofiber thin film of the present invention is not particularly limited, but has, for example, a structure as shown in FIGS. 1 and 2 in the accompanying drawings. The device can be used.

One example of a thermal CVD apparatus used to carry out the method of the present invention is disclosed in Japanese Patent Application No. 2000-89468.
It is the device described in the item. As shown in FIG. 1, this apparatus introduces a raw material gas together with a hydrogen gas into a stainless steel vacuum chamber 1 constituting a film forming chamber, and deposits a graphite nanofiber thin film on a substrate 3 to be processed mounted on a substrate holder 2. An infrared transmission window 4 made of heat-resistant glass such as quartz is provided on an upper wall surface of a vacuum chamber 1 facing a substrate holder 2, and a substrate heating device is provided outside the infrared transmission window 4. Infrared heater 5 for
Is provided so that the graphite nanofiber thin film can be formed on the substrate while the substrate 3 is heated by the infrared heater 5. The pressure in the vacuum chamber during the formation of the thin film is maintained at approximately 1 atm.
The heat treatment of the substrate 3 on which the metal thin film pattern is formed may be performed in the vacuum chamber 1 under vacuum.

The vacuum chamber 1 is connected to a vacuum pump 7 through a valve 6 so that the inside of the vacuum chamber 1 can be evacuated.
Is attached so that the pressure in the chamber can be monitored.

The vacuum chamber 1 also has a gas supply system 9.
Is connected. The gas supply system 9 includes a valve 10a
A source gas supply system connected in series to a source gas cylinder 10d of carbon monoxide gas or the like via a gas pipe via a gas flow controller 10b and a pressure controller 10c;
1a, a hydrogen gas supply system serially connected to a hydrogen gas cylinder 11d by a gas pipe via a gas flow controller 11b and a pressure regulator 11c is provided in parallel, and the raw material gas supply system and the hydrogen gas supply system It merges between the valves 10a and 11a and the vacuum chamber 1, and a mixed gas of a carbon-containing gas and a hydrogen gas is supplied into the vacuum chamber. The mixed gas is allowed to reach the target substrate 3 without being heated by the infrared heater 5.

A cooling means 12 for cooling the vacuum chamber is provided outside the vacuum chamber 1, the inner wall of the vacuum chamber 1 is covered with an insulator 13, the infrared transmission window 4 is made of heat-resistant glass, and , Substrate holder 2
May be provided with a resistance heater 14.

As shown in FIG. 2, another thermal CVD apparatus used for carrying out the method of the present invention is a vacuum chamber 21 made of a metal such as stainless steel which constitutes a film forming chamber.
And a load lock chamber 22. Arbitrary columns 25 for mounting a substrate holder 24 on which a substrate 23 is mounted are provided in the vacuum chamber 21, and a transfer robot 26 is provided in the load lock chamber 22.
Is provided. Also, in the load lock chamber 22,
A vacuum pump 27 is connected, and a vacuum gauge 29 is further attached so that the degree of vacuum in the room can be measured and monitored. The substrate holder 24 on which the substrate 23 is mounted is transferred from the substrate storage chamber to the load lock chamber 22 by the transfer robot 26. Next, after evacuating the inside of the load lock chamber 22 to a predetermined degree of vacuum (about 0.01 Torr), the gate valve 30 is opened,
The substrate holder 24 on which the substrate to be processed 23 is mounted is transported into the vacuum chamber 21 evacuated to a predetermined degree of vacuum, and is placed on the support 25. And the transfer robot 26
Is returned to the load lock chamber 22, the gate valve 30
Close. In the above description, the substrate holder is transported to transport the substrate holder 24 on which the substrate 23 to be processed is mounted. However, the substrate 23 transported to the substrate 23 and fixed on the support 25 in the vacuum chamber 21 is provided. The substrate may be transferred to place the substrate on the holder 24.

An infrared transmission window 31 made of heat-resistant glass such as quartz is provided on the upper wall surface of the vacuum chamber 21 so as to face the substrate 23 to be processed, and has a predetermined arrangement outside the window. A plurality of infrared lamps 32 are attached, and are configured to uniformly heat the substrate 23 to be processed.

A vacuum pump 34 is connected to the vacuum chamber 21 via a valve 33a, so that the inside of the vacuum chamber can be evacuated. Further, a pipe 28 that bypasses the vacuum pump 34 is provided with a valve 39 interposed. Further, a vacuum gauge 35 is attached to the vacuum chamber 21 at an arbitrary position so that the degree of vacuum in the vacuum chamber can be measured and monitored. The vacuum gauge 35 may be connected to any part of such an exhaust system. The heat treatment under vacuum of the substrate 23 on which the pattern of the metal thin film is formed may be performed in the vacuum chamber 21.

Further, a gas supply system 36 is connected to the vacuum chamber 21. The gas supply system 36 is connected to a source gas supply system connected in series to a source gas cylinder 37e of carbon monoxide or the like by a gas pipe via a valve 37a, a gas flow controller 37b, a pressure regulator 37c, and a valve 37d. , A hydrogen gas supply system connected in series to a hydrogen gas cylinder 38e via a gas pipe via a gas flow controller 38b, a pressure controller 38c, and a valve 38d from the valve 38a. The source gas supply system and the hydrogen gas supply system are provided with valves 37a, 38a and vacuum chamber 2
1 and is configured to supply a mixed gas of a carbon-containing gas and a hydrogen gas into the vacuum chamber 21. The introduction of the mixed gas is performed through gas injection nozzle means provided below the position where the substrate 23 or the substrate holder 24 is placed and surrounding the substrate near the outside thereof. The gas injection nozzle means connected to the gas supply system 36 has a gas flow path inside, and a plurality of gas injection ports communicating with the internal gas flow path are arranged on the upper surface thereof. Any shape can be used as long as the gas can be uniformly injected into the vacuum chamber. It is preferable that the gas injection nozzle means be disposed in surface contact with the bottom wall and / or the side wall surface in the vacuum chamber 21. This is for cooling the gas injection nozzle means. By providing such a gas injection nozzle means, when the mixed gas is injected upward from the plurality of gas injection ports, the mixed gas is uniformly diffused over the entire substrate 23 to be processed, and then downward. It descends uniformly and reaches uniformly over the whole substrate to be processed. Thus, a uniform film thickness distribution can be achieved. The gas injection nozzle means provided in the vacuum chamber 21 is preferably made of a metal having a high thermal conductivity such as Cu.

Further, the inner wall of the vacuum chamber 21 may be mirror-polished, or the inner wall may be coated with an insulator such as alumina by thermal spraying. This is to prevent the generated graphite nanofiber from adhering to the wall surface. In addition, in order to prevent graphite nanofibers from adhering to the vacuum chamber wall surface, as a means for cooling the wall surface, on the outer periphery of the chamber,
A cooling medium, for example, a cooling pipe through which cooling water flows may be provided. Further, a heating mechanism for preheating the mixed gas introduced into the vacuum chamber 21 may be provided.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG.
Hereinafter, formation of a graphite nanofiber thin film using the apparatus shown in (1) will be described with reference to examples. (Embodiment 1) 100 n of Fe was deposited only on a predetermined portion (pattern portion of a predetermined shape) on a glass substrate by EB vapor deposition.
m in thickness. The substrate 23 on which the Fe pattern is deposited in this manner is mounted on a substrate holder 24.
The substrate was placed on the substrate holder support 25 in the vacuum chamber 21 of the thermal CVD apparatus by the transfer robot 26 from the substrate storage room. Activate the vacuum pump 34 and operate the valve 3
3a and 33b were opened, and while the pressure in the vacuum chamber was measured with the vacuum gauge 35, the vacuum evacuation was performed until the pressure became about 0.05 Torr. In this state, the infrared lamp 3
2 was energized to bring the substrate temperature to 500 ° C., and a heat treatment under vacuum was performed at this temperature for 5 minutes. Thereafter, the main stoppers of the carbon monoxide gas cylinder 37e and the hydrogen gas cylinder 38e are opened, the pressure is adjusted to about 1 atm (absolute pressure) by the pressure regulators 37c, 38c, and the valves 37a, 38a are opened.
By the gas flow controllers 37b and 38b, a mixed gas of carbon monoxide gas and hydrogen gas (CO: H ₂ = 3 by volume ratio)
0:70) was adjusted to about 1000 sccm, and introduced into the vacuum chamber 21 from below the substrate holder 24 to be processed through gas injection nozzle means to perform gas replacement. At this time, the valves 33a and 33b are closed, the vacuum pump 34 is stopped, and the valve 39 of the bypass pipe 28 is closed.
Was kept in an open state, so that the inside of the vacuum chamber 21 was almost at atmospheric pressure (760 Torr). In this case, the mixed gas was introduced in a state where the substrate 23 was heated to 500 ° C. by energizing the infrared lamp 32.

In this embodiment, after the pressure in the vacuum chamber 21 reaches the atmospheric pressure, the infrared lamp 32 is energized to heat the substrate 23 to 500 ° C., and the thermal CVD is performed at this temperature for 20 minutes. A growth reaction of graphite nanofibers was performed on the substrate by the method. When the carbon monoxide gas reached the target substrate 23, the carbon monoxide was dissociated, and a graphite nanofiber thin film was formed only on the Fe thin film pattern deposited on the target substrate. The substrate after the growth reaction was taken out of the vacuum chamber 21 and the surface state was observed with a scanning electron microscope (SEM). As a result, the graphite nanofiber thin film grew only on the pattern where Fe was deposited. (A in FIG. 3: × 100), and it was confirmed that a large number of graphite nanofibers were growing on the substrate in a curled state (FIG. 4: × 40000). The diameter of the obtained graphite nanofiber is 10 nm to 100 n.
m.

Next, the characteristics of the electron emission source composed of the graphite nanofiber thin film thus obtained were measured. As a result, when the applied electric field reached 1 V / μm, the start of electron emission was confirmed. Thereafter, as the applied electric field was increased, the amount of electron emission increased, and reached about 100 mA / cm ² at 5 V / μm.

In order to examine the adhesion of the Fe thin film pattern to the substrate on the substrate on which the graphite nanofiber thin film obtained as described above is formed and on the substrate which has been subjected to the thermal CVD treatment in the same manner as described above without heat treatment. A thin film peeling test was performed to observe the peelability of the Fe thin film. As a result, when the film was formed by the thermal CVD method after performing the heat treatment, the peeling of the Fe thin film pattern was hardly observed, the pattern was retained, and the adhesion was good, but without performing the heat treatment. When a film is formed by the thermal CVD method, Fe
The thin film tended to peel slightly from the substrate. (Example 2) An Fe thin film having a thickness of 100 nm was formed only on a pattern portion having a predetermined shape on a glass substrate by a sputtering method. Next, a graphite nanofiber thin film was formed according to the same procedure as in Example 1. That is, F
The substrate holder 24 on which the substrate to be processed 23 having the pattern e is mounted is placed on the substrate holder support 25 in the vacuum chamber 21 of the thermal CVD apparatus shown in FIG. 2 by the transfer robot 26 from the substrate storage room. Then, after evacuating the inside of the vacuum chamber 21 to 0.05 Torr,
Heat treatment was performed under vacuum at a substrate temperature of 500 ° C. for 5 minutes. Thereafter, a mixed gas of hydrogen gas and carbon monoxide as a source gas was introduced into the vacuum chamber 21 at a volume ratio of CO: H ₂ = 30: 70, and gas replacement was performed. After the pressure in the vacuum chamber 21 was returned to the atmospheric pressure, the infrared lamp was energized, and a growth reaction of graphite nanofibers was performed on the substrate 23 by a thermal CVD method at 500 ° C. for 20 minutes. When the substrate after the growth reaction was observed by SEM, the same result as in Example 1 was obtained.

A thin film peeling test similar to that of Example 1 was conducted on the substrate on which the graphite nanofiber thin film obtained as described above was formed and on the substrate which had been subjected to the thermal CVD treatment in the same manner as described above without heat treatment. Then, the peeling property of the thin film was observed. As a result, when the film was formed by the thermal CVD method after the heat treatment, the peeling of the Fe thin film pattern was not observed, the pattern was retained, and the adhesion was good. When the film was formed by the CVD method, the Fe thin film tended to peel off slightly from the substrate.

In the above embodiment, an example was described in which a pattern of an Fe thin film was formed on a glass substrate, and a graphite nanofiber thin film was formed only on the pattern portion.
Similar results were obtained in the case of a Co thin film pattern, in the case of a thin film pattern of an alloy containing at least one of Fe and Co, and in the case of forming a metal thin film on a Si substrate.

[0035]

According to the method for forming a graphite nanofiber thin film of the present invention, a predetermined heat treatment is performed on the substrate to be processed before the growth of the graphite nanofiber by the thermal CVD method. The adhesion between them is improved. Therefore, by using this method,
A carbon-based electron emission source (cold cathode source) capable of achieving high electron emission density and low field electron emission performance can be manufactured and provided. A display element capable of emitting light in a desired portion can also be provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an example of a film forming apparatus for performing a method of the present invention.

FIG. 2 is a schematic configuration diagram showing another example of a film forming apparatus for performing the method of the present invention.

FIG. 3 is a scanning electron microscope (SEM) micrograph (× 100) of the graphite nanofiber obtained by the method of the present invention.

FIG. 4 is a scanning electron microscope (SEM) micrograph (× 40000) of the graphite nanofiber obtained by the method of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Vacuum chamber 2 Substrate holder 3 Substrate to be processed 4 Infrared transmission window 5 Infrared heater 6 Valve 7 Vacuum pump 8 Vacuum gauge 9 Gas supply system 10a, 11a
Valve 10b, 11b Gas flow controller 10c, 11c
Pressure regulator 10d, 11d Gas cylinder 12 Cooling means 13 Insulator 14 Resistance heating heater 21 Vacuum chamber 22 Load lock chamber 23 Substrate to be processed 24 Substrate holder 25 Post 26 Transfer robot 27 Vacuum pump 29 Vacuum gauge 30 Gate valve 31 Infrared transmission window 32 infrared lamps 33a, 33b
Valve 34 Vacuum pump 35 Valve 36 Gas supply system 37a, 38a
Valve 37b, 38b Gas flow controller 37c, 38c
Pressure regulator 37d, 38d Valve 37e, 38e
Gas cylinder 39 valve

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 4G046 CA01 CB01 CB03 CB09 CC06 CC08 EA06 EB04 EB13 EC01 EC03 EC06 4K030 AA14 AA17 BA27 BB14 CA04 CA06 DA02 DA04 FA10 JA06 JA09 JA10 KA24 LA11 4L037 CS04 FA03 FA05 FA20 PA03 PA06 PA06 UA02

Claims (7)

[Claims] 1. A method according to claim 1, wherein Fe, C,
o or a substrate on which a thin film of an alloy containing at least one of these metals is formed in a predetermined pattern is used as a substrate to be processed, and after the substrate to be processed is heat-treated under vacuum, a carbon-containing gas and A method for forming a graphite nanofiber thin film, wherein a graphite nanofiber is obtained by uniformly growing a graphite nanofiber only on a pattern portion on the substrate to be processed using hydrogen gas. 2. A method according to claim 1, wherein Fe or C is formed on a glass or Si substrate.
o or a substrate on which a thin film of an alloy containing at least one of these metals is formed in a predetermined pattern is used as a substrate to be processed, and the substrate to be processed, which is placed in a vacuum chamber evacuated, is irradiated with an infrared lamp. Heating, heat-treating the substrate under vacuum, then introducing a carbon-containing gas and a hydrogen gas into the vacuum chamber, maintaining the pressure in the vacuum chamber at approximately 1 atm, and forming a pattern on the substrate to be processed. A graphite nanofiber thin film forming method, wherein a graphite nanofiber thin film is obtained by uniformly growing graphite nanofibers only in a portion by a thermal CVD method. 3. The temperature for performing the heat treatment is 400 ° C. or higher,
3. The method for forming a graphite nanofiber thin film according to claim 1, wherein the temperature is not higher than the heat resistance temperature of the substrate. 4. The mixing ratio of the carbon-containing gas and the hydrogen gas is such that the carbon-containing gas / hydrogen gas is 0.1 to 1 on a volume basis.
The method for forming a graphite nanofiber thin film according to claim 1, wherein the value is zero. 5. The temperature for performing the thermal CVD method is 450 to 6
The method for forming a graphite nanofiber thin film according to claim 1, wherein the temperature is 50 ° C. 5. 6. The method for forming a graphite nanofiber thin film according to claim 1, wherein the carbon-containing gas is carbon monoxide or carbon dioxide. 7. A method of forming the metal thin film into a predetermined pattern, performing a heat treatment under vacuum, etching the surface of the thin film to roughen the surface state, and then performing a thermal CVD method. The method for forming a graphite nanofiber thin film according to any one of claims 1 to 6.