WO2006115242A1

WO2006115242A1 - Surface-treated fine particle, surface-treating apparatus, and method for surface-treating fine particle

Info

Publication number: WO2006115242A1
Application number: PCT/JP2006/308555
Authority: WO
Inventors: Takayuki Abe; Yuuji Honda
Original assignee: Youtec Co., Ltd.
Priority date: 2005-04-25
Filing date: 2006-04-24
Publication date: 2006-11-02
Also published as: JP5795390B2; JP5721923B2; JP2013176770A; JPWO2006115242A1; JP6069098B2; JP2014097502A

Abstract

Disclosed is a surface-treated fine particle which is surface-treated by a simple process while being precisely controlled in the degree of the surface treatment. Also disclosed are a surface-treating apparatus and a method for surface-treating fine particles. Specifically disclosed is a surface-treating apparatus for treating the surface of a fine particle (1), and this apparatus comprises a container (2) for holding the fine particle (1), a chamber (3) for housing the container (2), a heating mechanism (4) for heating the fine particle (1) held in the container (2), and a gas-introducing mechanism for introducing a gas into the chamber (3).

Description

Surface treatment fine particles, surface treatment apparatus, and surface treatment method for fine particles

The present invention relates to surface-treated fine particles, a surface treatment apparatus, and a surface treatment method. In particular, the present invention relates to a surface treatment fine particle, a surface treatment apparatus, and a fine particle surface treatment method in which surface treatment is performed with a simple process and the degree of the surface treatment is accurately controlled.

Background art

[0002] Powder is a very attractive sample both fundamentally and in application, and is currently used in various fields. For example, the fineness of the powder is used for cosmetic foundations, and the fine ferrite particles are used as a magnetic material applied to magnetic tape to form a single magnetic domain. It is also possible to produce a fine particle catalyst using the power of the surface area of the powder characteristics. As such, it is a material that has great potential, so new material development technology is required for surface treatment of powder to develop high-performance and new functions.

[0003] Conventionally, powder surface treatment has been performed by wet chemical etching! For example, a metal or oxide powder is subjected to a surface treatment by etching with an acid solution, a surface treatment by oxidation with an alkaline solution, and a surface treatment by fluorination with a fluoride solution. In addition, the polymer powder is subjected to surface treatment by etching with an organic solvent.

Problems to be solved by the invention

[0004] However, the above-described surface treatment method enables uniform surface treatment, but requires a plurality of steps such as filtration, washing, and drying, and thus the steps are complicated. In the case of wet surface treatment, it is difficult to treat the treatment solution. Also, it is extremely difficult to accurately control the degree of surface treatment (for example, the depth of surface treatment).

[0005] The present invention has been made in consideration of the above-mentioned circumstances, and its purpose is to carry out surface treatment with a simple process and to accurately control the degree of the surface treatment, An object of the present invention is to provide a processing apparatus and a surface treatment method for fine particles.

Means for solving the problem

In order to solve the above problems, the surface-treated fine particles according to the present invention are characterized in that the fine particles are surface-treated by heating or a plasma atmosphere. The plasma atmosphere includes a plasma atmosphere by sputtering.

[0007] The surface-treated fine particles according to the present invention rotate or stir the fine particles in the container by rotating a container having a substantially circular internal cross-sectional shape about the direction perpendicular to the cross-section. The fine particles are surface-treated while being rotated.

[0008] The surface-treated fine particles according to the present invention are obtained by stirring a fine particle in the container by rotating a container having a polygonal cross-sectional shape around a rotation axis that is substantially perpendicular to the cross-section. The fine particles are surface-treated while being rotated.

[0009] Further, in the surface-treated fine particles according to the present invention, the surface treatment may be a treatment of oxidizing, nitriding, fluorinating or carbonizing the surface of the fine particles.

Further, in the surface-treated fine particles according to the present invention, the surface treatment is a treatment for cleaning the surface of the fine particles with plasma, or a treatment for plasma-etching the surface of the fine particles to form irregularities on the surface of the fine particles. It is also possible. In the case of the cleaning process, an inert gas such as Ar may be used as the gas. In addition, an anchoring effect can be expected by performing a treatment for forming irregularities on the surface of the fine particles.

The surface treatment method for fine particles according to the present invention contains fine particles in a container,

The fine particles are surface-treated by heating or a plasma atmosphere. In addition, the plasma atmosphere includes a plasma atmosphere by snottering.

[0010] In the fine particle surface treatment method according to the present invention, the fine particles are contained in a container having a substantially circular internal shape in a cross section substantially parallel to the direction of gravity.

The fine particles in the container are surface-treated while the fine particles in the container are agitated or rotated by rotating the container about a direction substantially perpendicular to the cross section.

[0011] The fine particle surface treatment method according to the present invention has a cross section substantially parallel to the direction of gravity. The fine particles are stored in a polygonal container,

[0012] A surface treatment apparatus according to the present invention includes a container on which fine particles are placed;

A chamber containing the container;

A heating mechanism for heating the fine particles placed on the container;

A gas introduction mechanism for introducing gas into the chamber;

Comprising

The fine particles are surface-treated.

[0013] A surface treatment apparatus according to the present invention is a container that contains fine particles, the container having a substantially circular internal shape in a cross section substantially parallel to the direction of gravity;

A rotation mechanism that rotates the container about a direction substantially perpendicular to the cross section, and a heating mechanism that heats the fine particles contained in the container;

A gas introduction mechanism for introducing gas into the container;

Comprising

By rotating the container using the rotating mechanism, the fine particles in the container are surface-treated while stirring or rotating the fine particles in the container.

[0014] A surface treatment apparatus according to the present invention is a container that contains fine particles, the container having a polygonal internal shape in a cross section substantially parallel to the direction of gravity;

A gas introduction mechanism for introducing gas into the container;

Comprising

[0015] A surface treatment apparatus according to the present invention comprises a container for placing fine particles;

A chamber containing the container; A gas introduction mechanism for introducing gas into the chamber;

An electrode disposed in the chamber and disposed to face the container;

The fine particles are surface-treated using plasma.

[0016] A surface treatment apparatus according to the present invention is a container that contains fine particles, the container having a substantially circular inner shape in a cross section substantially parallel to the direction of gravity;

A rotation mechanism for rotating the container about a direction substantially perpendicular to the cross section, an electrode disposed in the container,

A gas introduction mechanism for introducing gas into the container;

Comprising

It is characterized in that the fine particles in the container are surface-treated by using plasma while stirring or rotating the fine particles in the container by rotating the container using the rotating mechanism.

[0017] A surface treatment apparatus according to the present invention is a container that contains fine particles, the container having a polygonal internal shape in a cross section substantially parallel to the direction of gravity;

A gas introduction mechanism for introducing gas into the container;

Comprising

[0018] In the surface treatment apparatus according to the present invention, the gas introduction mechanism may be a mechanism for introducing at least one of oxygen gas, nitrogen gas, fluorine gas, and hydrocarbon gas. is there. For example, methane gas can be used as the hydrocarbon gas.

In the surface treatment apparatus according to the present invention, the surface treatment may be a treatment for cleaning the surface of the fine particles with plasma or a surface of the fine particles for plasma etching. It is also possible to perform a process of forming irregularities on the surface of the fine particles by performing the chucking.

In the surface treatment apparatus according to the present invention, the gas introduction mechanism may include a mechanism for introducing a shower-like gas from the electrode into the container.

In the surface treatment apparatus according to the present invention, it is also possible to further include a chamber 1 that houses the container, and a vacuum exhaust mechanism that evacuates the chamber.

[0019] As described above, according to the present invention, there are provided a surface-treated fine particle, a surface treatment apparatus, and a fine particle surface treatment method in which the surface treatment is performed with a simple process and the degree of the surface treatment is accurately controlled. Can do.

Brief Description of Drawings

FIG. 1 is a configuration diagram showing an outline of a thermal surface treatment apparatus according to a first embodiment of the present invention.

2 is a cross-sectional view showing an example of surface-treated fine particles obtained by surface-treating fine particles with the thermal surface treatment apparatus shown in FIG.

[FIG. 3] (A) is a cross-sectional view schematically showing a thermal surface treatment apparatus according to Embodiment 2 of the present invention, and (B) is a cross section taken along line 3B-3B shown in (A). FIG.

[FIG. 4] (A) is a cross-sectional view schematically showing a thermal surface treatment apparatus according to Embodiment 3 of the present invention, and (B) is a cross section taken along line 4B-4B shown in (A). FIG.

5 is a cross-sectional view showing an example of surface-treated fine particles obtained by surface-treating fine particles with the thermal surface treatment apparatus shown in FIG.

FIG. 6 is a configuration diagram showing an outline of a plasma surface treatment apparatus according to a fourth embodiment of the present invention.

[FIG. 7] (A) is a cross-sectional view schematically showing a plasma surface treatment apparatus according to Embodiment 5 of the present invention, and (B) is a cross-sectional view taken along line 7B-7B shown in (A). It is.

[FIG. 8] (A) is a cross-sectional view schematically showing a plasma surface treatment apparatus according to Embodiment 6 of the present invention, and (B) is a cross-sectional view taken along line 8B-8B shown in (A). It is.

Explanation of symbols [0021] 1 ··· Powder (fine particles), 2 ··· Container, 3 ··· Chamber 1, 4 ··· Heater, 5 to 7, 11 ··· Piping, 12 ... Valve, 14 ... Mass flow controller (MFC), 15 ··· Gravity direction, 16 ··· Vacuum pump, 17 ··· Acid film, 18 ··· Surface-treated particles, 19 ··· Vessel, 20 ··· Chamber cover, 21 ··· Heater , 22 ··· Container, 23 ··· Surface treated fine particle, 24 ··· Gas shower electrode, 25 ··· Plasma power supply, 2 ··· Vacuum vacuum, 27 ··· Mass flow controller (MFC), 28 ··· Gas introduction source, 29, 30 ··· Container, 31 ··· Plasma power source, 32, 33… switch

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)

FIG. 1 is a configuration diagram showing an outline of a thermal surface treatment apparatus according to Embodiment 1 of the present invention. This thermal surface treatment apparatus is an apparatus for surface-treating fine particles (or powder).

[0023] The thermal surface treatment apparatus has a container 2 on which powder (fine particles) 1, for example, metal powder is placed or accommodated. A heater 4 as a heating mechanism for heating the powder 1 is disposed at the bottom of the container 2. The container 2 and the heater 4 are disposed in the chamber 1.

[0024] Further, the thermal surface treatment apparatus includes a gas introduction mechanism for introducing gas into the chamber 13. The gas introduction mechanism has a gas introduction mechanism for introducing O gas. Ga

2

The gas introduction mechanism consists of piping 5-7, valve 12, mass flow controller (MFC) 14 and O gas.

There are 2 sources.

[0025] The tip of the pipe 5 is connected to the chamber 1, and O gas is channeled from the tip of the pipe 5.

2

It seems to erupt into bar 3. The base end of the pipe 5 is connected to one side of the valve 12, and the other side of the valve 12 is connected to one end of the pipe 6. The other end of the pipe 6 is connected to one end of the mass flow controller 14, and the other end of the mass flow controller 14 is connected to one end of the pipe 7. The other end of the pipe 7 is connected to an O gas supply source.

2

The thermal surface treatment apparatus includes a vacuum pump 16 that evacuates the inside of the chamber 13. This vacuum pump 16 is connected to the chamber 1 by a pipe 11

Next, the surface on which the powder (fine particles) 1 is surface-treated using the thermal surface treatment apparatus. The processing method will be described.

First, a powder 1 in which many fine particles are collected is contained in a container 2. The amount of the powder 1 accommodated in the container 2 is preferably such that two to three layers having fine particle force are laminated. When the number of layers of fine particles is increased, oxygen (O) gas hardly reaches the fine particles in the lower layer.

2

Therefore, the surface treatment state of the lower layer fine particles is deteriorated. In addition, for example, Si powder or Ti powder is used in the present embodiment as the base material constituting the fine particles 1. The fine particles 1 do not necessarily need to be a single type of fine particles, and a plurality of types of fine particles can be used. Various shapes can be used as the shape of the fine particles 1, and for example, a sphere or a shape close to a sphere is preferable.

[0028] Next, while the powder 1 is heated to a predetermined temperature (for example, about 400 to 800 ° C) with the heater 4 through the container 2, the inside of the chamber 13 is maintained at a predetermined pressure (for example, the vacuum pump 16). Exhaust to 10 ^1-2 ~ ^10_4 Torr). Then, the valve 12 is opened, and oxygen gas whose flow rate is controlled by the mass flow controller 14 is introduced into the chamber 13 through the pipes 5-7. As a result, the surface treatment for oxidizing each fine particle surface of the powder 1 can be performed, and fine particles having a surface that can also be used for the acidity of the metal used can be produced. Further, in the present embodiment, oxygen gas is used, and therefore, the ability to form oxides. If hydrocarbon gas is used, carbide is formed, and if nitrogen gas is used, nitride is formed, and HS gas is formed.

If 2 is used, sulfide is formed.

FIG. 2 is a cross-sectional view showing an example of surface-treated fine particles obtained by surface-treating fine particles with the thermal surface treatment apparatus shown in FIG.

The surface-treated fine particles 18 are obtained by subjecting the fine particles 1 to surface treatment with relatively uniform uniformity, and forming an oxide film 17 on the surface of the fine particles 1. However, in the thermal surface treatment apparatus, the surface treatment of the bottom of the fine particles 1 (the portion on the side in contact with the container 2) is performed by performing the thermal surface treatment with the fine particles 1 contained in the container 2 stationary. As a result, the thickness of the oxide film formed by is reduced.

[0030] According to the first embodiment, by using the thermal surface treatment apparatus, the fine particles or the powder can be surface-treated in a simple process, and the degree of the surface treatment can be controlled with high accuracy. Can do. In other words, the surface treatment is performed by applying heat while suppressing the aggregation of the powder. Therefore, it is possible to control the degree of surface treatment with high accuracy with a simple process.

In the present embodiment, when a surface treatment is performed to oxidize the surface of the fine particles that are also s, the surface of the fine particles can be insulated.

[0031] (Embodiment 2)

FIG. 3 (A) is a cross-sectional view schematically showing the thermal surface treatment apparatus according to Embodiment 2 of the present invention, and FIG. 3 (B) is taken along the line 3B-3B shown in FIG. 3 (A). FIG. This thermal surface treatment apparatus is an apparatus for surface-treating fine particles (or powder).

This thermal surface treatment apparatus has a cylindrical chamber 13. Both ends of the chamber 13 are closed by a chamber lid 20. A container 19 is disposed inside the chamber 13. The container 19 has a cylindrical portion (round barrel), and the powder (fine particles) 1 is accommodated inside the round barrel. The cross section shown in Fig. 3 (B) is a cross section substantially parallel to the direction of gravity. In the present embodiment, a force using a container 19 having a substantially circular cross-sectional shape is not limited to this, and a container having a substantially elliptical cross-sectional shape may be used.

[0033] The container 19 is provided with a rotating mechanism (not shown). By rotating the container 19 as indicated by the arrow by this rotating mechanism, the powder (fine particles) 1 in the container 19 is stirred or rotated. In addition, surface treatment is performed. A rotation axis when the container 19 is rotated by the rotation mechanism is an axis parallel to a substantially horizontal direction (a direction perpendicular to the gravity direction). A heater 21 is disposed on the outer surface of the container 19 as a heating mechanism for heating the powder 1.

The thermal surface treatment apparatus is provided with a gas introduction mechanism that introduces gas into the container 19. The gas introduction mechanism has a gas introduction mechanism for introducing O gas. Gas guide

2

The structure of the insertion mechanism is substantially the same as in the first embodiment. The thermal surface treatment apparatus also includes a vacuum pump (not shown) that evacuates the inside of the chamber 3.

[0035] Next, a method for surface-treating powder (fine particles) 1, for example, metal powder such as Ti or Si, using the thermal surface treatment apparatus will be described.

First, a powder 1 in which many fine particles are collected is stored in a container 19. It should be noted that force capable of using various materials as the powder 1 In this embodiment, for example, Si powder or Ti powder is used as in the first embodiment. [0036] Next, while the powder 1 is heated to a predetermined temperature (for example, about 400 to 800 ° C) by the heater 4 through the container 19, the inside of the chamber 13 is heated to a predetermined pressure (for example, about 400 to 800 ° C) ( For example, exhaust 10 to about ² to 10 ^_4 Torr). Then, oxygen gas whose flow rate is controlled by the gas introduction mechanism is introduced into the container 19, and the container 19 is rotated by the rotation mechanism at a predetermined rotation speed (for example, 15 rpm) for a predetermined time (for example, 120 minutes). The powder 1 inside is rotated and stirred. As a result, a surface treatment is performed to uniformly oxidize the surface of each fine particle of the powder 1, and fine particles having a surface having an acidity of the metal used can be produced.

[0037] In the second embodiment, the same effect as in the first embodiment can be obtained.

Further, according to the present embodiment, since the powder itself can be rotated and stirred by rotating the container 19 itself of the round barrel, the agglomeration of the powder due to moisture or electrostatic force, which is often a problem when handling the powder. Can be prevented. Therefore, fine particles having a very small particle diameter can be surface-treated in a simple process, and the degree of the surface treatment can be accurately controlled.

[0038] (Embodiment 3)

FIG. 4 (A) is a cross-sectional view schematically showing the thermal surface treatment apparatus according to Embodiment 3 of the present invention, and FIG. 4 (B) is along the line 4B-4B shown in FIG. 4 (A). FIG. In FIG. 4, the same parts as those of FIG.

[0039] A container 22 is disposed inside the chamber 13. The container 22 has a hexagonal barrel shape (hexagonal barrel shape) as shown in FIG. 4B. Then, powder (fine particles) 1 is accommodated in the container 22. The cross section shown in Fig. 4 (B) is a cross section substantially parallel to the direction of gravity. In this embodiment, the hexagonal barrel-shaped container 22 is used, but a polygonal barrel-shaped container other than the hexagonal shape is not limited to this.

The container 22 is provided with a rotation mechanism (not shown) as in the second embodiment. By rotating the container 22 as indicated by the arrows by this rotating mechanism, the surface treatment is performed while stirring or rotating the powder (fine particles) 1 in the container 22. The rotation axis when the container 22 is rotated by the rotation mechanism is substantially parallel to the horizontal direction (perpendicular to the direction of gravity). Is the axis.

In addition, a heating mechanism is arranged on the outer surface of the container 22 as in the second embodiment. The thermal surface treatment apparatus includes a gas introduction mechanism and a vacuum pump as in the second embodiment.

[0042] Next, a method for surface-treating powder (fine particles) 1 using the thermal surface treatment apparatus will be described.

First, a powder 1 in which many fine particles are collected is stored in a container 19. It should be noted that various materials can be used as the powder 1. In the present embodiment, for example, Ti powder or Si powder is used as in the first embodiment.

Next, the chamber 13 is evacuated to a predetermined pressure using a vacuum pump while the powder 1 is heated to a predetermined temperature via the container 22 by the heater 4. Then, oxygen gas whose flow rate is controlled by the gas introduction mechanism is introduced into the container 22, and the container 1 is rotated at a predetermined rotation speed for a predetermined time by the rotation mechanism, whereby the powder 1 in the container 22 is rotated. Stir. As a result, a surface treatment can be performed in which the surface of each fine particle of the powder 1 is oxidized with good uniformity, and fine particles having a surface that can also be used for the acidity of the metal used can be produced.

FIG. 5 is a cross-sectional view showing an example of surface-treated fine particles obtained by surface-treating fine particles with the thermal surface treatment apparatus shown in FIG.

The surface-treated fine particles 23 are obtained by finely treating the fine particles 1 with good uniformity and forming the oxide film 17 on the fine particles 1 with good uniformity. In the thermal surface treatment apparatus, since the surface treatment is performed while rotating and stirring the fine particles 1 by rotating the container 22, the entire surface of the fine particles 1 can be surface treated with good uniformity. In addition, the oxide film can be formed with good uniformity. Even if the surface of the fine particles 1 has irregularities or depressions, the irregularities or depressions can be surface treated with good uniformity.

[0045] In the third embodiment, the same effect as in the first embodiment can be obtained.

Further, according to the present embodiment, the powder itself can be rotated and stirred by rotating the hexagonal barrel-shaped container 22 itself, and further, the powder can be periodically removed by gravity by making the barrel hexagonal. Can be dropped. For this reason, the stirring efficiency can be dramatically improved as compared with the second embodiment, and moisture and static electricity often cause problems when handling powder. Aggregation of powder due to force can be prevented. That is, stirring by rotation and pulverization of the agglomerated powder can be performed simultaneously and effectively. Therefore, fine particles having a very small particle diameter can be surface-treated by a simple process, and the degree of the surface treatment can be controlled with high accuracy. Specifically, it is possible to surface-treat fine particles having a particle size of 50 m or less.

It should be noted that the present invention is not limited to Embodiments 1 to 3 above, and can be carried out by being modified as follows. For example, other surface treatments can be performed after plasma cleaning or plasma etching. That is, after performing plasma cleaning with Ar gas, surface treatment is performed with a gas other than Ar (for example, O gas).

2

It is also possible.

In Embodiments 1 to 3, oxygen gas is introduced by the gas introduction mechanism. However, the gas is not limited to oxygen gas, for example, nitrogen gas, fluorine gas, hydrocarbon gas, nitrogen. Alternatively, a gas containing fluorine or the like can be introduced by a gas introduction mechanism. For example, when surface treatment is performed in which nitrogen gas or a gas containing nitrogen is introduced by a gas introduction mechanism and the surface of the fine particles of Si is nitrided, the surface of the fine particles is Si N

A nitride film of 3 4 is formed, and the surface of the fine particles can be cured by this nitride film. Further, for example, when a surface treatment is performed in which fluorine gas or a gas containing fluorine is introduced by a gas introduction mechanism and the surface of the fine particles is fluorinated, a CF film is formed on the surface of the fine particles.

Four

[0047] (Embodiment 4)

FIG. 6 is a configuration diagram showing an outline of the plasma surface treatment apparatus according to the fourth embodiment of the present invention. This plasma surface treatment apparatus is an apparatus for surface-treating fine particles (or powder).

The plasma surface treatment apparatus has a chamber 13. In the chamber 13, a container 2 for storing powder (fine particles) 1 to be coated is disposed. The container 2 is connected to a plasma power source 31 or a ground potential, and both can be switched by a switch 32.

[0049] The plasma surface treatment apparatus has a gas introduction mechanism for introducing gas into the chamber 13. I have. This gas introduction mechanism has a cylindrical gas shower electrode 24, and this gas shower electrode 24 is arranged in the chamber 13. On one side of the gas shower electrode 24, a plurality of gas outlets for blowing out one or more gases in a shower shape are formed. The gas outlet is arranged so as to face the powder 1 contained in the container. The other side of the gas shower electrode 24 is connected to one side of a mass flow controller (MFC) 27 via a vacuum valve 26. The other side of the mass flow controller 27 is connected to a gas introduction source 28 via a vacuum valve and a filter (not shown). This gas introduction source 28 is different in the type of gas to be introduced depending on the surface treatment of the powder. However, in the case of performing the surface treatment with oxygen, it is an introduction source of oxygen gas or a gas containing oxygen, and the surface treatment by nitriding Is a source of introduction of nitrogen gas or a gas containing nitrogen, a source of introduction of fluorine gas or a gas containing fluorine when performing a surface treatment by fluorination, and methane, etc. when a surface treatment by carbonization is conducted. This is a hydrocarbon gas introduction source, and an inert gas introduction source such as argon when surface treatment is performed by plasma cleaning.

In addition, the plasma surface treatment apparatus includes a plasma power supply mechanism, and the plasma power supply mechanism includes a plasma power source 25 connected to the gas shower electrode 24 via a switch 33. The plasma power supplies 25 and 31 are a high-frequency power supply that supplies high-frequency power (RF output), a microwave power supply, a DC discharge power supply, and a pulse-modulated high-frequency power supply, microwave power supply, and DC discharge power supply, respectively. Either one is acceptable. For example, when the plasma power supply supplies high-frequency power, it is preferable to place an impedance matching device (matching box) (not shown) between the high-frequency power supply and the gas shower electrode 24. That is, in this case, the gas shower electrode 24 is connected to a matching box, and the matching box is connected to a high frequency power source (RF power source) via a coaxial cable.

A plasma power supply may be connected to one of the gas shower electrode 24 and the container 2 and a ground potential may be connected to the other, or a plasma power supply may be connected to both the gas shower electrode 24 and the container 2. It ’s okay!

[0051] Further, the plasma surface treatment apparatus includes an evacuation mechanism for evacuating the inside of the chamber 13. For example, the gas shower electrode 12 has an exhaust port (shown in the figure) for exhausting the inside of the chamber 13. And a plurality of exhaust ports are connected to a vacuum pump (not shown).

[0052] Next, a method for surface-treating the powder 1 using the plasma surface treatment apparatus will be described.

First, powder 1 composed of a plurality of fine particles is stored in a container 2. The amount of powder 1 accommodated in the container 2 and the material of the powder are the same as in the first embodiment. Thereafter, the inside of the chamber ^{13 is} evacuated to a predetermined pressure (for example, about 10 ² to 10 ^_4 Torr) by operating a vacuum pump.

[0053] Next, the vacuum nozzle 26 is opened, and a gas (for example, oxygen gas) is introduced into the mass flow controller 27 at the gas introduction source 28, and the flow rate is controlled by the mass flow controller 27. The introduced gas is introduced inside the gas shower electrode 24. Then, a gas blower gas from the gas shower electrode is blown out.

Thereafter, an RF output of 13.56 MHz, for example, is supplied to the gas shower electrode 24 from a high frequency power source (RF power source) which is an example of the plasma power source 25 via, for example, a matching box. At this time, the container 2 is connected to the ground potential. As a result, plasma is ignited between the gas shower electrode 24 and the container 2. At this time, the matching box matches the impedance of the container 2 and the gas shear electrode 24 by the inductance and the capacitance C. As a result, plasma is generated in the chamber 13 and surface treatment is performed to oxidize the surface of the fine particles 1 with uniformity, and fine particles having a surface made of an oxide of the metal used can be produced. .

[0055] According to the fourth embodiment, by using the plasma surface treatment apparatus, the fine particles or the powder can be surface-treated in a simple process, and the degree of the surface treatment can be controlled with high accuracy. Can do. For example, when oxygen gas or a gas containing oxygen is introduced by a gas introduction mechanism and a surface treatment is performed to oxidize the surface of fine particles such as S, an oxide film is formed on the surface of the fine particles. The surface of the fine particles can be insulated by the film. In addition, when a surface treatment is performed in which nitrogen gas or a gas containing nitrogen is introduced by a gas introduction mechanism to nitride the surface of fine particles made of Si, Si N force is not applied to the surface of the fine particles.

A nitride film is formed, and the surface of the fine particles can be cured by this nitride film. In addition, the gas introduction mechanism introduces fluorine gas or fluorine-containing gas, and fine particles with C force When a surface treatment is performed to fluorinate the surface of the film, a CF film is formed on the surface of the fine particles.

4 Further, when a surface treatment for carbonizing the surface of the fine particles by introducing a hydrocarbon gas such as methane by the gas introduction mechanism, carbides are formed on the surfaces of the fine particles. Further, when surface treatment is performed in which argon gas is introduced by a gas introduction mechanism and the surface of the fine particles is plasma-cleaned, the surface of the fine particles can be plasma-cleaned. For example, when fine particles having an oxide film formed on the surface are subjected to plasma cleaning, the oxide film on the surface of the fine particles can be removed, and fine particles having an active surface can be formed. In addition, in the surface treatment by etching, minute irregularities can be formed on the surface, and an anchoring effect can be obtained in surface modification and the like.

[0056] In the present embodiment, since the surface treatment is performed using plasma, the fine particles can be surface-treated with good uniformity even at a low temperature of 100 ° C or lower. Therefore, it is easy to decompose at high temperature of 100 ° C or more! / Vaginal particles and phase changes!

[0057] (Embodiment 5)

FIG. 7 (A) is a cross-sectional view schematically showing a plasma surface treatment apparatus according to Embodiment 5 of the present invention, and FIG. 7 (B) is taken along line 7B-7B shown in FIG. 7 (A). It is sectional drawing. This plasma surface treatment apparatus is an apparatus for surface-treating fine particles (or powder).

[0058] The plasma surface treatment apparatus has a cylindrical chamber 13. Both ends of the chamber 1 3 are closed by a chamber lid 20. A container 29 is disposed inside the chamber 13. The container 29 has a cylindrical portion (round barrel), and the powder (fine particles) 1 as an object to be coated is accommodated inside the round barrel. The container 29 also functions as an electrode and is connected to a plasma power source 31 or a ground potential, and both can be switched by a switch 32. The cross section shown in FIG. 7B is a cross section substantially parallel to the direction of gravity. In the present embodiment, the container 29 having a substantially circular cross section is used. However, the present invention is not limited to this, and a container having a substantially elliptical cross section may be used.

[0059] The container 29 is provided with a rotation mechanism (not shown), and the rotation mechanism rotates the container 29 as indicated by an arrow around the gas shear electrode 24 as a rotation center. The surface treatment is performed while stirring or rotating the powder (fine particles) 1. The rotation axis when the container 29 is rotated by the rotation mechanism is an axis parallel to a substantially horizontal direction (a direction perpendicular to the direction of gravity). Further, the airtightness in the chamber 13 is maintained even when the container 29 is rotated.

In addition, the plasma surface treatment apparatus includes a gas introduction mechanism that introduces gas into the chamber 13. This gas introduction mechanism has a cylindrical gas shower electrode 24, and this gas shower electrode 24 is arranged in a container 29. That is, an opening is formed on one side of the container 29, and the gas shower electrode 24 is inserted into this opening force. The gas shutter electrode 24 is formed with a plurality of gas outlets for blowing out one or more gases in a shower shape. The gas outlet is arranged so as to face the powder 1 contained in the container. As shown in FIG. 7B, the gas outlet is arranged in the direction of about 1 ° to 90 ° in the rotation direction of the container 29 with respect to the direction of gravity 15.

[0061] As with the fourth embodiment, the gas shower electrode 24 is a vacuum valve and a mass flow controller.

(MFC), a vacuum valve, a filter, and a gas introduction source (not shown). Since this gas introduction source is the same as that in the fourth embodiment, description thereof is omitted.

In addition, the plasma surface treatment apparatus includes a plasma power supply mechanism, and this plasma power supply mechanism has a structure similar to that of the fourth embodiment. In addition, the plasma surface processing apparatus includes a vacuum exhaust mechanism that exhausts the inside of the chamber 13 and the structure of the vacuum exhaust mechanism is substantially the same as that of the fourth embodiment.

[0063] Next, a method for surface-treating the powder 1 using the plasma surface treatment apparatus will be described.

First, powder 1 composed of a plurality of fine particles is stored in a container 2. It is to be noted that various materials can be used as the powder 1. In the present embodiment, for example, Ti powder or Si powder is used as in the first embodiment. Thereafter, evacuate the chamber one 3 to a predetermined pressure (e.g., 10 one ² ~ 10_ approximately ⁴⁾ by actuating the vacuum pump. At the same time, the container 29 is rotated by the rotating mechanism, so that the powder (fine particles) 1 contained in the container 29 moves while rolling between the gravitational direction 30 and 90 ° in the rotational direction on the inner surface of the container.

[0064] Next, in the gas introduction source, gas (for example, oxygen gas) is introduced to the mass flow controller. The flow rate is controlled by the mass flow controller, and the gas whose flow rate is controlled is introduced into the gas shower electrode 24. The gas blowout force of the gas shower electrode also blows out the gas. As a result, gas is blown to the fine particles 1 moving while rolling in the container 29, and the pressure suitable for the surface treatment is maintained by the balance between the controlled gas flow rate and the exhaust capacity.

Thereafter, an RF output of 13.56 MHz, for example, is supplied to the gas shower electrode 24 from a high frequency power source (RF power source) which is an example of the plasma power source 25 via, for example, a matching box. At this time, the container 29 is connected to the ground potential. As a result, plasma is ignited between the gas shower electrode 24 and the container 29. At this time, the matching box is matched with the impedance of the container 2 and the gas shutter electrode 24 by the inductance and the capacitance C. As a result, plasma is generated in the container 29, and a surface treatment is performed to uniformly oxidize the surface of the fine particles 1 to produce fine particles having a surface made of SiO or TiO.

2

You can. That is, since the fine particles 1 are rolled by rotating the container 29, it is possible to easily perform the surface treatment on the entire surface of the fine particles 1 with good uniformity.

[0066] In the fifth embodiment, the same effect as in the fourth embodiment can be obtained.

Further, according to the present embodiment, since the powder itself can be rotated and stirred by rotating the container 29 itself of the round barrel, the agglomeration of the powder due to moisture or electrostatic force, which is often a problem when handling the powder. Can be prevented. Therefore, fine particles having a very small particle diameter can be surface-treated in a simple process, and the degree of the surface treatment can be accurately controlled.

[Embodiment 6]

FIG. 8 (A) is a cross-sectional view schematically showing a plasma surface treatment apparatus according to Embodiment 6 of the present invention, and FIG. 8 (B) is taken along line 8B-8B shown in FIG. 8 (A). It is sectional drawing. In FIG. 8, the same parts as those of FIG. 7 are denoted by the same reference numerals, and the description of the same parts is omitted.

A container 30 is disposed inside the chamber 13. This container 30 has a hexagonal barrel shape (hexagonal barrel shape) as shown in FIG. 8B. The container 30 accommodates powder (fine particles) 1 that is an object to be coated. The container 30 also functions as an electrode and is connected to the plasma power source 31 or the ground potential. Both can be switched by switch 32. The cross section shown in Fig. 8 (B) is a cross section substantially parallel to the direction of gravity. In the present embodiment, the force using the hexagonal barrel-shaped container 30 is not limited to this, and a polygonal barrel-shaped container other than the hexagon can also be used.

The container 30 is provided with a rotation mechanism (not shown) as in the fifth embodiment. By rotating the container 30 as indicated by an arrow by this rotating mechanism, the surface treatment is performed while stirring or rotating the powder (fine particles) 1 in the container 30. A rotation axis when the container 30 is rotated by the rotation mechanism is an axis parallel to a substantially horizontal direction (a direction perpendicular to the direction of gravity).

In addition, the plasma surface treatment apparatus includes a gas introduction mechanism and a vacuum exhaust mechanism as in the fifth embodiment. This gas introduction mechanism has a cylindrical gas shower electrode 24 as in the fifth embodiment. In addition, the plasma surface treatment apparatus includes a plasma power supply mechanism as in the fifth embodiment.

Next, a method for surface-treating powder (fine particles) 1 using the plasma surface treatment apparatus will be described.

First, the powder 1 having a plurality of fine particle forces is accommodated in the container 30. It should be noted that various materials can be used as the powder 1. In the present embodiment, for example, Ti powder or Si powder is used as in the first embodiment. Thereafter, the inside of the chamber 3 is evacuated to a predetermined pressure (for example, about ^10_2 to ^10_4 Torr) by operating the vacuum pump. At the same time, the container 30 is rotated by the rotating mechanism, whereby the powder (fine particles) 1 contained therein is stirred or rotated on the inner surface of the container.

Next, a gas (for example, oxygen gas) is introduced into the mass flow controller at the gas introduction source, the flow rate is controlled by the mass flow controller, and the gas whose flow rate is controlled is introduced into the gas shower electrode 24. Then, gas is blown out from the gas outlet of the gas shower electrode. As a result, gas is blown onto the fine particles 1 that are moving while stirring or rotating in the container 30, and the pressure suitable for the surface treatment is maintained by the balance between the controlled gas flow rate and the exhaust capacity.

Thereafter, the plasma power source 25 is connected to the gas shower electrode 24 via, for example, a matching box. An RF output of 13.56 MHz, for example, is supplied from a high-frequency power source (RF power source) that is an example. At this time, the container 30 is connected to the ground potential. Thereby, plasma is ignited between the gas shower electrode 24 and the container 30. At this time, the matching box is matched with the impedance of the container 2 and the gas shutter electrode 24 by the inductance and the capacitance C. As a result, plasma is generated in the container 30, and the surface treatment of oxidizing the surface of the fine particles 1 with good uniformity is performed to produce fine particles having a surface made of SiO or TiO.

2

You can. That is, since the fine particles 1 are agitated and rotated by rotating the container 30, it is possible to easily treat the entire surface of the fine particles 1 with good uniformity.

[0074] In Embodiment 6 described above, the same effects as in Embodiment 4 can be obtained.

According to the present embodiment, the powder itself can be rotated and stirred by rotating the hexagonal barrel-shaped container 30 itself. Further, by making the barrel hexagonal, the powder is periodically removed by gravity. Can be dropped. For this reason, the stirring efficiency can be drastically improved as compared with Embodiment 5, and aggregation of the powder due to moisture and electrostatic force, which is often a problem when handling the powder, can be prevented. That is, stirring by rotation and pulverization of the agglomerated powder can be performed simultaneously and effectively. Therefore, it is possible to surface-treat fine particles having a very small particle diameter by a simple process. Specifically, it is possible to surface-treat fine particles having a particle size of 50 m or less.

Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the conditions for surface treatment of the fine particles can be appropriately changed.

Claims

The scope of the claims

[1] Surface-treated fine particles, wherein the fine particles are surface-treated by heating or a plasma atmosphere.

[2] By rotating a container having a substantially circular internal cross-sectional shape about a direction perpendicular to the cross section as a rotation axis, the fine particles were surface-treated while stirring or rotating the fine particles in the container. Surface-treated fine particles characterized by the above.

[3] By rotating a container having an internal cross-sectional shape of a polygon about a direction substantially perpendicular to the cross section as a rotation axis, the fine particles were surface-treated while stirring or rotating the fine particles in the container. Surface-treated fine particles characterized by the above.

[4] The surface-treated fine particles according to any one of claims 1 to 3, wherein the surface treatment is a treatment of oxidizing, nitriding, fluorinating, or carbonizing the surface of the fine particles.

[5] The surface treatment is a treatment for cleaning the surface of the fine particles with plasma, or

4. The surface-treated fine particles according to claim 1, wherein the surface-treated fine particles are plasma-etched to form irregularities on the surface of the fine particles.

[6] containing fine particles in a container;

A fine particle surface treatment method, wherein the fine particles are surface-treated by heating or a plasma atmosphere.

[7] The fine particles are housed in a container having a substantially circular internal shape with a cross section substantially parallel to the direction of gravity.

A fine particle surface treatment method characterized in that the fine particles in the container are surface-treated while the fine particles in the container are agitated or rotated by rotating the container about a direction substantially perpendicular to the cross section.

[8] The fine particles are contained in a container having a polygonal internal shape with a cross section substantially parallel to the direction of gravity.

[9] a container for placing fine particles;

A chamber containing the container;

A heating mechanism for heating the fine particles placed on the container;

A gas introduction mechanism for introducing gas into the chamber;

Comprising

A surface treatment apparatus characterized by surface-treating the fine particles.

[10] A container for storing fine particles, wherein the inner shape of a cross section substantially parallel to the direction of gravity is substantially circular;

A gas introduction mechanism for introducing gas into the container;

Comprising

A surface treatment apparatus characterized in that the fine particles in the container are surface-treated while stirring or rotating the fine particles in the container by rotating the container using the rotating mechanism.

[11] A container for storing fine particles, the container having a polygonal internal shape in a cross section substantially parallel to the direction of gravity;

A gas introduction mechanism for introducing gas into the container;

Comprising

[12] a container for placing the fine particles;

A chamber containing the container;

A gas introduction mechanism for introducing gas into the chamber;

An electrode disposed in the chamber and disposed to face the container;

A surface treatment apparatus characterized by surface-treating the fine particles using plasma.

[13] A container for storing fine particles, the container having a substantially circular internal shape in a cross section substantially parallel to the direction of gravity;

A gas introduction mechanism for introducing gas into the container;

Comprising

A surface treatment apparatus characterized in that the fine particles in the container are surface-treated by using plasma while stirring or rotating the fine particles in the container by rotating the container using the rotating mechanism.

[14] A container for storing fine particles, the container having a polygonal internal shape in a cross section substantially parallel to the direction of gravity;

A gas introduction mechanism for introducing gas into the container;

Comprising

[15] The surface according to any one of [9] to [14], wherein the gas introduction mechanism is a mechanism for introducing at least one of oxygen gas, nitrogen gas, fluorine gas, and hydrocarbon gas. Processing equipment.

[16] The surface treatment may be a process of cleaning the surface of the fine particles with plasma, or a process of plasma etching the surface of the fine particles to form irregularities on the surface of the fine particles. The surface treatment apparatus as described in any one of 12 thru | or 14

[17] The surface treatment apparatus according to any one of [12] to [14], wherein the gas introduction mechanism includes a mechanism for introducing a shower-like gas from the electrode cover into the container. 15. The surface treatment apparatus according to claim 12, further comprising: a chamber that accommodates the container; and a vacuum exhaust mechanism that evacuates the chamber.