KR20200038012A - Apparatus of plasma atomic layer depositing on powder - Google Patents

Abstract

The present invention relates to an atomic layer deposition device for powder, which can form a uniform coating film on a surface of the powder. The atomic layer deposition device for powder comprises: a mesh structure configured to load powder in a chamber; a shower head disposed below the mesh structure and disposed below the chamber by supplying raw material gas, purge gas, and plasmaized reaction gas from bottom to top to provide the same to the powder; and an exhaust portion disposed above the chamber to exhaust the raw material gas, purge gas, and plasmaized reaction gas to the outside.

Description

Apparatus of plasma atomic layer depositing on powder

The present invention relates to an atomic layer deposition apparatus and a deposition method, and more particularly, to an atomic layer deposition apparatus and deposition method for powder that can form a coating film on the powder using plasma.

Various methods have been tried to form a film on the powder. For example, it is possible to form a plating film on a powder by a plating process. However, the plating process involves the harmfulness of the working conditions and environmental pollution, and the plating film that can be formed according to the material of the powder is limited. In addition, although it is possible to form a coating film on a powder by a chemical vapor deposition process, it is difficult to form a uniform coating film on the surface of the powder, and there is a problem that a high temperature is required to form a coating film of an oxide film or a nitride film.

1. Public Patent Publication 10-2014-0107843 (September 05, 2014)

The technical problem to be achieved by the present invention is to provide a plasma atomic layer deposition apparatus and a deposition method for powders capable of forming a uniform coating film on the surface of the powder with high productivity and low process temperature. However, these problems are exemplary, and the scope of the present invention is not limited thereby.

Provided is a plasma atomic layer deposition apparatus for powders according to one aspect of the present invention for solving the above problems. The plasma atomic layer deposition apparatus for powder may include a mesh structure configured to load powder in a chamber; A shower head disposed below the mesh structure and disposed below the chamber to supply raw material gas, purge gas and plasmad reaction gas from below to above to provide the powder; And an exhaust portion disposed above the chamber to exhaust the raw material gas, purge gas, and plasmad reaction gas to the outside. It includes.

In the plasma atomic layer deposition apparatus for powder, the mesh structure is configured such that the size of the mesh does not directly contact the powder and the shower head, and the plasma for forming the plasmad reaction gas includes the mesh and the shower head. It is generated in the space between, the shower head may be an electrode for forming the plasma.

The plasma atomic layer deposition apparatus for powder is interposed between the mesh structure and the shower head, and includes a through hole so that raw material gas, purge gas, and plasmad reaction gas pass from the bottom to the top, and form the plasma. In the process of serving as a ground, a ground structure; may further include.

In the plasma atomic layer deposition apparatus for powder, the mesh structure is configured so that the size of the mesh does not directly contact the powder and the shower head, and the plasma for forming the plasmad reaction gas includes the ground structure and the shower It is generated in the space between the heads, and the shower head may be an electrode for forming the plasma.

In the plasma atomic layer deposition apparatus for powder, the plasma may be a CCP plasma (Capacitively Coupled Plasma).

In the plasma atomic layer deposition apparatus for powder, the chamber may include an external reactor and an internal reactor capable of being mounted and detached inside the external reactor and capable of loading the powder.

In the plasma atomic layer deposition apparatus for powder, the mesh structure and the showerhead may be located inside the outer reactor but may be disposed below the inner reactor.

Provided is a plasma atomic layer deposition method for powders according to another aspect of the present invention for solving the above problems. The plasma atomic layer deposition method for powder may include loading powder on a mesh structure in a chamber; And an adsorption step of adsorbing at least a portion of the raw material gas to the powder by providing a raw material gas from the bottom to the top of the mesh structure, a first purge step of providing a purge gas from the bottom of the mesh structure to the top, the mesh structure. A unit comprising a reaction step of forming a unit deposition film on the surface of the powder by providing a reaction gas plasmad to the powder from below to above and a second purge step of providing a purge gas from below to above the mesh structure. And performing the cycle at least once or more.

The plasma atomic layer deposition method for the powder further includes the step of evacuating the source gas, the purge gas and the plasmad reaction gas to the outside, wherein the source gas, the purge gas and the plasmad reaction gas is exhausted from the chamber The position to be may be higher than the position where the powder is loaded.

In the plasma atomic layer deposition method for the powder, the adsorption step, the first purge step, the reaction step, and the second purge step may include a step in which at least a portion of the powder is suspended on the mesh structure.

In the plasma atomic layer deposition method for the powder, the chamber includes an external reactor and an internal reactor capable of being mounted and detached inside the external reactor, and the mesh structure is disposed at the bottom to load the powder. The step of loading the powder on the mesh structure in the chamber includes loading the powder into the inner reactor and then mounting the inner reactor inside the outer reactor, after performing the unit cycle at least once or more. It may further include the step of detaching the inner reactor mounted on the inside of the outer reactor to the outside.

According to one embodiment of the present invention made as described above, it is possible to implement a plasma atomic layer deposition apparatus and a deposition method for powders capable of forming a uniform coating film on the surface of the powder with high productivity and low process temperature. Of course, the scope of the present invention is not limited by these effects.

1 is a view schematically illustrating a plasma atomic layer deposition apparatus for powder according to an embodiment of the present invention.
FIG. 2 is an enlarged view of a shower head, a power source, and a grounding portion in the plasma atomic layer deposition apparatus for powder shown in FIG. 1.
3 is a flow chart illustrating a deposition method using a plasma atomic layer deposition apparatus for powder according to an embodiment of the present invention.
4 is a view schematically illustrating a plasma atomic layer deposition apparatus for powder according to a modified embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms, and the following embodiments make the disclosure of the present invention complete, and the scope of the invention to those skilled in the art It is provided to inform you completely. Also, for convenience of description, the size of at least some of the components may be exaggerated or reduced in the drawings. The same reference numerals in the drawings refer to the same elements.

According to the plasma atomic layer deposition apparatus for powder and a deposition method using the same according to embodiments of the present invention, it is impossible to perform in a conventional thermal atomic layer deposition apparatus by providing a plasma generating apparatus configuration in a powder reactor It is possible to deposit a substance such as an oxide film or a nitride film metal that requires high temperature conditions on the surface of the powder.

When the object to be treated is a powder, it is generally not easy to configure a plasma generating device inside the powder reactor, and various problems when configuring a plasma generating device of a remote plasma and an inductively coupled plasma (ICP) type Have

In the case of a long-distance plasma (report plasma), a separate plasma generating device must be configured and supplied through a pipe to a powder processing device. From the viewpoint of generating plasma, a plasma is activated with an inert gas separately, and a reactive gas is secondarily supplied. Therefore, since the reaction gas needs to be activated with plasma, there may be a problem that a separate process time is added according to the plasma activation step. Sufficient reaction can be achieved only by supplying gas, however, a large amount of gas and piping connected to the remote plasma generator and the powder reactor may cause an increase in purge time and uneven powder dispersion during the atomic layer deposition.

Next, when the coil-type inductively coupled plasma is installed outside the powder reactor, plasma must be generated at a pressure lower than a few to several tens of mTorr, which is a pressure range required for plasma generation, depending on the amount of gas supplied when performing atomic layer deposition. Since the pressure is hundreds of mTorr to several Torr, plasma generation is not easy, and since the plasma is not directly exposed to the lower portion of the powder loaded in the reactor, uneven deposition of each powder particle may occur.

Next, when a capacitive-coupled plasma (CCP) generator is configured inside the powder reactor, when metal powder is processed, metal powder is directly attached to the electrode or plasma is not generated when connected to the ground of the reactor outer wall. Problems may arise, micro arcing and non-uniform plasma may occur. In addition, when the plasma is generated from the top, since the plasma is not directly exposed to the bottom of the powder loaded in the reactor, uneven deposition of each powder particle may occur. The present invention configures a capacitively coupled plasma generator at the bottom of the reactor to overcome the above problems.

1 is a view schematically illustrating a plasma atomic layer deposition apparatus for powders according to an embodiment of the present invention, and FIG. 2 shows a shower head, a power supply, and a ground part in the plasma atomic layer deposition apparatus for powders shown in FIG. 1. It is a diagram enlarged and illustrated.

1 and 2, the plasma atomic layer deposition apparatus 100 for powder according to an embodiment of the present invention is a mesh structure 130 configured to load the powder 150 in the chambers 110 and 140 ; A shower head disposed under the mesh structure 130, but provided under the chambers 110 and 140 to supply raw material gas, purge gas, and plasmad reaction gas from the bottom to the top to provide the powder 150 ( 134); And an exhaust unit 120 disposed above the chambers 110 and 140 to exhaust the raw material gas, the purge gas and the plasmad reaction gas to the outside. It includes.

The plasma atomic layer deposition apparatus 100 for powder according to an embodiment of the present invention is interposed between the mesh structure 130 and the shower head 134, but the raw material gas, the purge gas and the plasmad reaction gas are upwardly downward. It may include a through-hole to pass through, and serves as a ground in the process of forming the plasma (P), a ground structure 136; may further include. The raw material gas, the purge gas and the reaction gas that is plasmad include a through hole to pass from the bottom to the top, and in the sense that it serves as a ground in the process of forming the plasma (P), the ground structure 136 is a ground shower head It may be understood as.

The mesh structure 130 is configured so that the size of the mesh does not directly contact the powder 150 and the shower head 134, and the plasma P for forming the plasmad reaction gas is showered with the ground structure 136. It is generated in the space between the heads 134, and the shower head 134 may also serve as an electrode for forming the plasma P. The plasma P may be a CCP plasma (Capacitively Coupled Plasma).

The plasma P generated by the plasma generating device having the ground structure 136, which is understood as the ground shower head, may be understood as a kind of remote plasma. In the atomic layer deposition apparatus for powder, the plasma device may be supplied with a plasma, a reactive gas such as radicals, ions, electrons, etc. in a remote form, and plasma may be directly supplied through a ground showerhead hole.

An electrical insulating member 135 is interposed between the shower head 134 and the chambers 110 and 140.

Meanwhile, the chambers 110 and 140 may include an outer reactor 110 and an inner reactor 140 capable of mounting and detaching inside the outer reactor 110 and capable of loading the powder 150. The mesh structure 130 and the showerhead 134 may be located inside the outer reactor 110 but disposed below the inner reactor 140. That is, the mesh structure 130 and the showerhead 134 may be positioned at a lower level than the bottom of the inner reactor 140. The source gas and the gas that can be plasmad may be supplied through a shower head capable of generating plasma installed below the external reactor 110 through a supply port 170 of the external reactor 110.

The method capable of generating plasma includes both the DC method and the RF method, and the frequency capable of generating the AC plasma may include both low-frequency and high-frequency methods from several kHz to several GHz.

3 is a flow chart illustrating a deposition method using a plasma atomic layer deposition apparatus for powder according to an embodiment of the present invention.

Referring to FIG. 3, the deposition method using the plasma atomic layer deposition apparatus 100 for powder according to an embodiment of the present invention is a plasma atomic layer deposition method for powder, and the mesh structure 130 in the chambers 110 and 140 Step of loading the powder 150 on (S100); And an adsorption step (S210) of adsorbing at least a portion of the raw material gas to the powder 150 by providing the raw material gas from the bottom to the top of the mesh structure 130, and providing a purge gas from the bottom of the mesh structure 130 to the top. A first purge step (S220), a reaction step (S230) of forming a unit deposition film on the surface of the powder 150 by providing a plasma-like reaction gas to the powder 150 from the bottom to the top of the mesh structure 130 and It includes; performing at least one or more unit cycles (S200) having a second purge step (S240) for providing purge gas from the bottom of the mesh structure 130 upward.

In the adsorption step (S210), the first purge step (S220), the reaction step (S230), and the second purge step (S240), at least a part of the powder 150 is floating on the mesh structure 130 ).

The raw material gas, purge gas and plasma reaction gas are set to flow from the lower side of the mesh structure 130 upwards, so that the powder 150 is directed upward by the flow of the raw material gas, the purge gas and the plasmad reaction gas. Receives the power of

In addition, the deposition method using the plasma atomic layer deposition apparatus 100 for powder according to an embodiment of the present invention may further include evacuating the raw material gas, the purge gas and the plasmad reaction gas to the outside. The position where the raw material gas, purge gas and plasma reaction gas are exhausted from the chambers 110 and 140 is set higher than the position where the powder 150 is loaded, so that the powder 150 is placed in the chambers 110 and 140. It is possible to receive an upward force due to the pressure of the exhaust unit 120 disposed above.

After all, the powder 150 receives the downward force F1 by gravity, and at the same time, the upward force F2 and the chambers 110 and 140 by the flow of the raw material gas, the purge gas and the plasmad reaction gas. ) Receives the upward force (F3) by the pressure of the exhaust portion 120 disposed above. Therefore, by properly adjusting the sizes of F1, F2, and F3, the powder 150 having a self-weight can repeat floating and sedimentation on the mesh structure 130 at an appropriate ratio. As a result of this, the uniformity of the coating film deposited on the surface of the powder 150 may be improved while the powder 150 on the mesh structure 130 is uniformly stirred while the unit cycle S200 is deposited while being repeated at least once or more. .

If the powder 150 on the mesh structure 130 is not agitated smoothly, the powder located relatively adjacent to the mesh of the mesh structure 130 is formed on the powder surface by frequent exposure to the source gas and the reaction gas. While the coated film is relatively thick, the powder located relatively far from the mesh of the mesh structure 130 is rarely in contact with the raw material gas and the reaction gas, so that the coating film formed on the powder surface is relatively thin, resulting in uniformity of the coating film. It becomes poor.

In the step (S100) of loading the powder 150 on the mesh structure 130 in the chambers 110 and 140, the chambers 110 and 140 are mounted inside the outer reactor 110 and the outer reactor 110, and Desorption is possible and may include an internal reactor 140 capable of loading powder 150.

According to this, the step (S100) of loading the powder 150 on the mesh structure 130 in the chambers 110 and 140, the powder 150 is loaded into the inner reactor 140, and then the inner reactor 140 is external. It may include a step of mounting inside the reactor (110). The mesh structure 130 may be provided in a state combined with the inner reactor 140.

The deposition method using the plasma atomic layer deposition apparatus 100 for powders according to an embodiment of the present invention is an inner reactor mounted inside the outer reactor 110 after the step of performing the unit cycle (S200) at least once or more 140) may further include detaching the device 100 from the outside.

Meanwhile, the filter unit 139 illustrated in FIG. 1 is a problem that occurs during a process of depositing a coating film on a powder by an atomic layer deposition process, resulting in direct powder loss to the exhaust stage 120 and productivity due to clogging of the exhaust stage. It is provided to prevent degradation.

4 is a view schematically illustrating a plasma atomic layer deposition apparatus for powder according to a modified embodiment of the present invention.

Referring to FIG. 4, a plasma atomic layer deposition apparatus 100 for powder according to a modified embodiment of the present invention includes a mesh structure 130 configured to load powder 150 in chambers 110 and 140; A shower head disposed under the mesh structure 130, but provided under the chambers 110 and 140 to supply raw material gas, purge gas, and plasmad reaction gas from the bottom to the top to provide the powder 150 ( 134); And an exhaust unit 120 disposed above the chambers 110 and 140 to exhaust the raw material gas, the purge gas and the plasmad reaction gas to the outside. It includes.

The mesh structure 130 may be configured to have a mesh size so that the powder 150 and the shower head 134 do not directly contact each other. Plasma (P) for forming the plasmad reaction gas is generated in a space between the mesh structure 130 and the shower head 134, and the shower head 134 of the electrode for forming the plasma (P) Can play a role. The plasma P illustrated in FIG. 4 may be understood as a direct plasma.

Descriptions of other components shown in FIG. 4 are the same as those described in FIG. 1 and will be omitted herein.

The reactor of the plasma atomic layer deposition apparatus for powders according to the above-described embodiments of the present invention is characterized in that a raw material gas and a reaction gas capable of being plasmad are supplied through a shower head device under the reactor. Plasma treatment of the powder loaded in the internal reactor is characterized in that the plasma activated through the plasma generating device installed at the bottom of the reactor is supplied to the lower portion of the powder particles, and further, is supplied between the respective powders to be exhausted to the upper exhaust portion. . The plasma generator installed inside the reactor includes a capacitively coupled plasma structure. In order to prevent the powder from being directly exposed to the electrode, which is a component of the plasma generating device, a mesh structure having a mesh network smaller than the powder size capable of loading the powder in an internal reactor is introduced. Direct plasma and remote plasma can be selectively generated according to the combination of the electrode for forming an electric field for generating plasma and the ground showerhead that can serve as a ground. For example, when the ground shower head is removed, a direct plasma can be generated, and when the ground shower head is included, a remote plasma can be generated.

In order to generate the plasma in the deposition apparatus for powder, it may be assumed that a direct plasma generating device is configured inside or supplied externally in a remote form through a remote plasma device, but a capacitive overlapping direct is applied to the top or bottom of the reactor. When the plasma is constituted, powder is attached to the electrode, and accordingly, non-uniform plasma is generated. In addition, it is difficult to supply the reaction gas smoothly to the inside of the powder, and it is difficult to perform plasma atomic layer deposition because the plasma contact is not smooth due to fluctuations in the electrical contact according to the powder flow.

In addition, in order to generate plasma by mounting a remote plasma generator externally, plasma must be generated through a step of supplying an active gas and an inert gas separately, and a large amount of gas must be supplied. When a large amount of gas is supplied, the reactor Powder loaded therein may be lost in the exhaust direction, and uniform deposition characteristics and exhaust and purge times may increase due to pressure increase during the process, resulting in reduced productivity.

In the plasma atomic layer deposition apparatus of the present embodiment described above, the capacitively coupled plasma apparatus is disposed under the powder loaded in the reactor, so that an electric short problem is not generated when plasma is generated, and the plasmad reaction gas is remote and direct. By supplying the powder inside, short plasma generation time and small amount of gas supply can shorten the plasma atomic layer deposition time, generate stable plasma, and can be performed at low temperature in the conventional thermal atomic layer deposition method. It is possible to easily form an oxide film, a nitride film, or a metal material without, and to implement an excellent thin film according to the plasma atomic layer deposition method, and a short purge time for the reaction gas reduces the deposition process time, thereby obtaining high productivity.

Although the present invention has been described with reference to the embodiments shown in the drawings, these are merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

100: atomic layer deposition apparatus for powder
110: external reactor
120: exhaust
130: mesh structure
134: shower head
136: ground structure
140: internal reactor
150: powder

Claims (6)

A mesh structure configured to load powder in the chamber;
A shower head disposed under the mesh structure and disposed under the chamber to supply raw material gas, purge gas, and plasmad reaction gas from bottom to top to provide the powder; And
An exhaust unit disposed above the chamber to exhaust the raw material gas, the purge gas, and the plasmad reaction gas to the outside; Containing,
Plasma atomic layer deposition device for powder. According to claim 1,
The mesh structure has a size of a mesh so that the powder and the shower head do not directly contact each other, and plasma for forming the plasmad reaction gas is generated in a space between the mesh and the shower head, and the shower head Serves as an electrode for forming the plasma,
Plasma atomic layer deposition device for powder. According to claim 1,
Interposed between the mesh structure and the shower head, including a through-hole so that the raw material gas, purge gas and plasma reaction gas passes from the bottom to the top, and serves as a ground in the process of forming the plasma, a ground structure Containing more;
Plasma atomic layer deposition device for powder. The method of claim 3,
The mesh structure has a size of a mesh so that the powder and the shower head do not directly contact each other, and plasma for forming the plasmad reaction gas is generated in a space between the ground structure and the shower head, and the shower The head serves as an electrode for forming the plasma,
Plasma atomic layer deposition device for powder. According to claim 1,
The plasma is characterized in that the CCP plasma (Capacitively Coupled Plasma),
Plasma atomic layer deposition device for powder. According to claim 1,
The chamber includes an external reactor and an internal reactor capable of being mounted and detached inside the external reactor and capable of loading the powder,
Plasma atomic layer deposition device for powder.

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