KR102182690B1 - Internal member applying plasma treatment apparatus and method for manufacturing the same - Google Patents

Abstract

The method of manufacturing an inner material for a plasma processing apparatus includes forming a thermal spray coating layer through a first ceramic material on an internal component of a vacuum chamber providing a plasma processing space, and dispersing particles from the thermal spray coating layer by melting a part of the surface of the thermal spray coating layer. Forming a surface-melted layer having a densified surface, and forming a surface supplementary layer on the surface-melted layer by using an aerosol deposition method through a second ceramic material.

Description

Inner material for plasma processing apparatus and its manufacturing method TECHNICAL FIELD {INTERNAL MEMBER APPLYING PLASMA TREATMENT APPARATUS AND METHOD FOR MANUFACTURING THE SAME}

The present invention relates to an inner material for a plasma processing apparatus and a method of manufacturing the same, and more particularly, the interior of a vacuum chamber of a plasma processing apparatus in which a process of treating a conductive thin film through plasma to form a circuit pattern on a substrate is performed. It relates to an inner material included in the and a method of manufacturing the same.

In general, semiconductor devices are manufactured by forming a circuit pattern on a semiconductor substrate such as a wafer. At this time, the circuit pattern is a conductive thin film such as aluminum (Al), titanium (Ti), molybdenum (Mo), tungsten (W), or molybdenum disilicide (MoSi2), titanium nitride (TiN), tantalum nitride (TaN). The process includes a deposition process of depositing a metal compound to form a wiring or an electrode, and a plasma etching process of etching a portion of the deposited wiring or electrode through plasma.

Here, the plasma etching process includes a chamber providing a processing space, a stage disposed in the processing space on which the semiconductor substrate is placed, and a plasma electrode disposed to face the stage in the vacuum chamber to generate the plasma. It proceeds through a plasma processing apparatus including.

In this case, an inner material is formed inside the chamber to be protected from plasma generated in the processing space. The inner material basically includes a thermal spray coating layer that is thermally spray-coated through a ceramic material so as to have excellent plasma resistance, and a surface melting layer in which the strength of the thermal spray coating layer is increased due to the denser particle distribution than the thermal spray coating layer by melting a part of the surface of the thermal spray coating layer.

However, when a part of the surface of the thermal spray coating layer is melt-treated in the process of forming the surface melting layer, as the density increases due to the decrease in pores that existed inside the thermal spray coating layer, the volume decreases and Due to the occurrence of thermal cracks, impurities due to erosion damage may be generated in the plasma etching process in the thermal crack portion, thereby contaminating the semiconductor substrate placed on the stage.

(Patent Document 1) Korean Patent Publication (No. 10-2009-0048114; Publication date 2009.05.13, plasma etching chamber) (Patent Document 2) Korean Patent Publication (No. 10-2008-0102254; Publication date 2008.11.24, Method of manufacturing a ceramic coating member for a semiconductor processing device)

It is an object of the present invention to provide a method of forming an inner material such that a finely formed thermal crack portion in an inner part of a vacuum chamber providing a plasma processing space is compensated.

In addition, another object of the present invention is to provide an inner material manufactured inside the vacuum chamber.

In order to achieve the object of the present invention described above, a method of manufacturing an inner material for a plasma processing apparatus according to a feature includes the steps of forming a thermal spray coating layer through a first ceramic material on an internal component of a vacuum chamber providing a plasma processing space, the And forming a surface melting layer having a denser particle distribution than the thermal spray coating layer by melting a part of the surface of the thermal spray coating layer, and forming a surface supplementary layer on the surface melting layer through a second ceramic material.

At least one component of the second ceramic material according to an embodiment may be the same as that of the first ceramic material.

In the step of forming the superficial melting layer according to an exemplary embodiment, microgrooves may be formed on the surface of the superficial melting layer. Accordingly, in forming the surface supplementation layer, the surface supplementation layer may be formed so that the second ceramic material is formed in the micro grooves.

The method of manufacturing the inner material according to an embodiment may further include removing the remaining surface residues of the surface supplementation layer except for the portion formed in the micro grooves after forming the surface supplementary layer. .

In the step of forming the surface melting layer according to an embodiment, in forming the surface melting layer, microgrooves may be formed on the surface of the surface melting layer. Thus, in the step of forming the surface supplementary layer, the second ceramic material includes ceramic particles having a size that is 10 times or less larger than that of the micro grooves to form the surface supplementation layer by using the aerosol deposition method. can do.

In forming the surface supplementation layer according to an embodiment, the surface supplementation layer may be formed to a thickness of 5 to 10 μm.

The method of manufacturing the inner material according to an embodiment may further include polishing the surface of the thermal spray coating layer before forming the surface molten layer.

In the polishing step according to an embodiment, the average roughness of the center line of the thermal spray coating layer may be 3 μm or less, or the ten point average roughness may be about 20 μm or less.

In the step of forming the thermal spray coating layer according to an embodiment, the thermal spray coating layer may be formed to a thickness of 50 to 300 μm.

In the step of forming the surface melting layer according to an embodiment, the surface melting layer may be formed to a thickness of 10 to 30 μm.

In order to achieve another object of the present invention described above, the inner material for a plasma processing apparatus according to one feature includes a thermal spray coating layer, a surface melting layer, and a surface supplementing layer.

The thermal spray coating layer is formed through a first ceramic material on an internal component of a vacuum chamber providing a plasma processing space. The surface molten layer is formed by melting a part of the surface of the thermal sprayed coating layer to have a denser particle distribution than the thermal sprayed coating layer, and fine grooves are formed on the surface. The surface supplementary layer is formed to penetrate the micro grooves through the second ceramic material on the surface melting layer.

The surface supplementation layer according to an embodiment may be formed limited to the micro grooves so that all portions of the surface melting layer except for the micro grooves are exposed.

According to such an inner material for a plasma processing apparatus and a method of manufacturing the same, a thermal spray coating layer and a part of the surface of the thermal spray coating layer are melt-treated to protect from the plasma in an internal part of a vacuum chamber providing a plasma processing space for processing a substrate through plasma. After forming the surface molten layer, fine grooves due to thermal cracks naturally formed on the surface during the process of forming the surface molten layer on the surface molten layer are penetrated and filled according to the aerosol deposition method. By forming the surface supplementary layer, it is possible to fundamentally prevent the generation of impurities due to erosion damage during the treatment process by the plasma from the micro grooves caused by the thermal crack.

Accordingly, it is possible to increase the production yield of semiconductor chips or display devices manufactured from the substrate processed by the plasma, and contribute to improving their quality.

1 is a schematic diagram of a plasma processing apparatus in which an inner material is formed according to an embodiment of the present invention.
2 to 5 are views for explaining step by step a method of substantially forming the inner material shown in FIG. 1.
6 is an enlarged view of part A of FIG. 5.
7 to 10 are SEM photographs showing the surfaces of the molten surface layer according to FIG. 4 according to the surface roughness in the polishing process according to FIG. 3.

Hereinafter, an inner material for a plasma processing apparatus and a method of manufacturing the same according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the present invention, various modifications may be made and various forms may be applied, and specific embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to a specific form disclosed, it should be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the present invention. In describing each drawing, similar reference numerals have been used for similar elements. In the accompanying drawings, the dimensions of the structures are shown to be enlarged compared to the actual size for clarity of the present invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. These terms are used only for the purpose of distinguishing one component from another component. For example, without departing from the scope of the present invention, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present application, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance the possibility of being added.

Meanwhile, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the technical field to which the present invention belongs. Terms as defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted as an ideal or excessively formal meaning unless explicitly defined in this application. Does not.

1 is a schematic diagram of a plasma processing apparatus in which an inner material is formed according to an embodiment of the present invention.

Referring to FIG. 1, an inner material 500 according to an embodiment of the present invention is formed on an internal component of a vacuum chamber 200 that provides a plasma processing space 210 in a high vacuum state of the plasma processing apparatus 100. .

At this time, the plasma processing apparatus 100 is basically disposed in the plasma processing space 210 to perform a plasma processing process on the substrate 10 and the stage 300 on which the substrate 10 is placed, and It may include a plasma electrode 400 for generating plasma by being disposed to face the substrate 10 placed on the stage 300. Accordingly, the inner material 500 may include not only the stage 300 and the plasma electrode 400, but also other components such as an inner wall or a baffle structure that may be located inside the vacuum chamber 200. . Here, the substrate 10 may include a semiconductor substrate for manufacturing semiconductor chips or a glass substrate for manufacturing display devices.

Accordingly, the inner material 500 needs excellent plasma resistance in order to protect the inner portion of the vacuum chamber 200 from the plasma in the plasma processing space 210, and hereinafter, the inner material 500 A method according to an embodiment of substantially forming a will be described in more detail with additional reference to FIGS. 2 to 6.

2 to 5 are views for explaining stepwise a method of substantially forming the inner material shown in FIG. 1, and FIG. 6 is an enlarged view of part A of FIG. 5.

Referring additionally to FIG. 2, in order to form the inner material 500, a first ceramic material is spray coated on the inner wall 220, which is one of the inner parts of the vacuum chamber 200, to form the thermal spray coating layer 600. To form. Here, the first ceramic material is a group of oxides of yttria, yttrium-aluminum garnet (YAG), alumina, zirconia, and periodic table 3a group having excellent plasma resistance while thermal spray coating is possible. It may be made of single or mixed materials selected from. When the thermal spray coating layer 600 has a thickness (T1) of less than about 50 μm, the inner wall 220, which is the base material, may be damaged by heat in the process of forming the thermal spray coating layer 600, as well as being too thin. It is not preferable because it is easily peeled off during the formation of the surface molten layer 700 below and is substantially difficult to form. If it exceeds about 300 μm, it is too thick to be peeled during the formation of the molten layer 700 below. Not only is this high, but it is not desirable because it increases the process cost due to the excessive thickness. Therefore, it is preferable that the thermal spray coating layer 600 has a thickness (T1) of about 50 to 300 μm. In addition, it is more preferable that the thermal spray coating layer 600 has a thickness (T1) of about 50 to 150 μm. A plurality of rough grooves 610 having a centerline average roughness (Ra) of about 4 to 5 μm or a ten point average roughness (Rz) of about 30 to 40 μm may be formed on the surface of the thermal spray coating layer 600 thus formed.

Referring additionally to FIG. 3, a polishing surface 620 is then formed by polishing the surface on which the rough grooves 610 of the thermal spray coating layer 600 are formed. The reason for polishing the surface of the thermal spray coating layer 600 in this way is to substantially form the surface melting layer 700 to be described below in most of the area of the thermal spray coating layer 600, and specific details according to this It will be described later.

Referring additionally to FIG. 4, a portion of the polishing surface 620 is subsequently melt-treated to form a surface melt layer 700 having a denser particle distribution than that of the thermal spray coating layer 600. Specifically, the surface melting layer 700 may be formed by heating the polishing surface 620 to a high temperature, and performing a process such as flame heating, arc irradiation, laser irradiation, or electron beam heating alone or in combination. As the surface melting layer 700 has a considerably stronger strength than the thermal spray coating layer 600, the inner wall 220 may substantially protect the inner wall 220 from the plasma in the plasma processing space 210. .

At this time, when the thickness T2 is less than about 10 μm, the surface melting layer 700 is not preferable because it is difficult to stably and uniformly form the entire area of the polishing surface 620 because it is too thin. If it exceeds, not only can it be easily peeled off because it is too thick, but it is not preferable because it takes an excessively large amount of time to form it. Therefore, it is preferable that the surface melting layer 700 has a thickness T2 of about 10 to 30 μm. The thickness T2 of the surface melting layer 700 may be implemented by controlling the distance between the heat source for heating to the high temperature or controlling the melting temperature by controlling the output of the heat source.

In addition, since the area ratio of the surface melting layer 700 may be determined according to the surface roughness of the polishing surface 620, this will be described in detail with additional reference to FIGS. 7 to 10 and Table 1 below. I want to.

7 to 10 are SEM photographs showing the surfaces of the molten surface layer according to FIG. 4 according to the surface roughness in the polishing process according to FIG. 3.

surface
asperity Ra More than 4㎛ and less than 5㎛ More than 3㎛ and less than 4㎛ More than 2㎛ and less than 3㎛ More than 1㎛ and less than 2㎛ Rz More than 30㎛ and less than 40㎛ More than 30㎛ and less than 35㎛ More than 13㎛ and less than 20㎛ More than 10㎛ and less than 12㎛ Surface melting layer area ratio 50% or more and less than 60% 70% or more and less than 80% More than 90% and less than 100% 100%

Referring to Tables 1 and 8, in the polishing process according to FIG. 3, the polishing surface 620 has a centerline average roughness Ra of more than about 4 µm and less than 5 µm or a ten point average roughness of more than about 30 µm and less than 40 µm. When proceeding to have (Rz), the actual area ratio of the surface melting layer 700 according to FIG. 4 is about 50% or more and less than 60%, and the inner material 100 does not have a desired level of plasma resistance. Was confirmed.

In addition, referring to Tables 1 and 9, the polishing process according to FIG. 3 is performed with a centerline average roughness Ra of more than about 3 μm and 4 μm or less, or a ten point average of more than about 30 μm and 35 μm or less. When proceeding to have a roughness (Rz), the actual area ratio of the surface melting layer 700 according to FIG. 4 is about 70% or more and less than 80%, and the inner material 100 also exhibits a desired level of plasma resistance. It was confirmed not to have.

On the other hand, referring to Tables 1, 10, and 11, the polishing process according to FIG. 3 was performed with the polishing surface 620 having a centerline average roughness Ra of about 3 μm or less or a ten-point average roughness Rz of about 20 μm or less. ), the actual area ratio of the surface melting layer 700 according to FIG. 4 is about 90% or more and appears in most of the area of the thermal spray coating layer 600, so that the inner material 100 is at a desired level. As it has plasma resistance, it is possible to substantially sufficiently stably protect the inner wall 220 from the plasma, so that the polishing process can be performed with a center line average roughness Ra of about 3 μm or less or It is preferable to proceed so as to have a ten point average roughness (Rz) of about 20 μm or less. In addition, it is more preferable to perform the polishing process so that the polishing surface 620 has a centerline average roughness (Ra) of about 3 μm or less and a ten point average roughness (Rz) of about 20 μm or less.

On the other hand, the surface melting layer 700 formed according to FIG. 4 is a process of curing the surface by heating at the high temperature, even when the thickness T2 or the surface roughness of the polishing surface 620 is adjusted as described above. Naturally, as the density increases due to the decrease in pores existing inside the thermal spray coating layer, the volume decreases, and fine grooves 710 due to thermal cracks are inevitably formed on the surface.

To compensate for this, the surface supplementary layer 800 is formed on the surface melting layer 700 by using an aerosol deposition method through a second ceramic material with additional reference to FIGS. 5 and 6.

Specifically, the surface supplementary layer 800 proceeds under vacuum according to the aerosol deposition method, and the ceramic particles made of the second ceramic material collide with the surface melting layer 700 at high speed, so that the surface melting layer It may be formed at the high density on the 700. Accordingly, the surface supplementary layer 800 may be formed while the ceramic particles naturally penetrate into the micro grooves 710 of the surface melting layer 700 and fill them.

At this time, since the ceramic particles collide with the surface melting layer 700 at high speed according to the aerosol deposition method, the size thereof is substantially larger than the width of the micro grooves 710 by about 10 times or less. Even if it is pulverized by the high-speed collision, it can penetrate and fill the fine grooves 710. For example, when the width of the micro grooves 710 is less than about 1 μm, the ceramic particles may have a size less than about 10 μm. As a result, the micro grooves 710 may be filled with nano-sized ceramic materials. In addition, the surface supplementary layer 800 formed as described above may have a form in which the micro grooves 710 penetrated to a depth of about 5 μm, for example.

Meanwhile, the second ceramic material used to form the surface supplementary layer 800 is, like the first ceramic material, yttria, yttrium-aluminum garnet (YAG), alumina, zirconia. (zirconia) and a group of oxides of Group 3a of the periodic table may be formed of a single or mixed material. At this time, the second ceramic material has the same first ceramic material as the first ceramic material of the thermal spray coating layer 600, which is the basis of the surface melting layer 700, so that the bonding strength with the surface melting layer 700 is excellent. It can be made of material. For example, when the first ceramic material is made of YAG (yttrium-aluminum garnet, YAG), the second ceramic material may be made of yttria or alumina.

In addition, when the thickness (T3) of the surface supplementary layer 800 is less than about 5 μm, it is not preferable because it cannot be uniformly formed on the surface melting layer 700, and when it exceeds about 10 μm, the surface It is not preferable because it may be peeled off from the molten layer 700. Therefore, it is preferable that the surface complementary layer 800 has a thickness T3 of about 5 to 10 μm.

In this way, after forming the thermal spray coating layer 600 and the surface melting layer 700 to be basically protected from the plasma on the inner wall 220 of the vacuum chamber 200 providing the plasma processing space 210 , In the process of forming the superficial melting layer 700 on the superficial melting layer 700, the microgrooves 710 due to the thermal cracks that cannot but be naturally formed on the surface are formed according to an aerosol deposition method. By forming the surface supplementary layer 800 that penetrates and fills, it is possible to fundamentally prevent impurities from being generated from the micro grooves 710 due to the thermal crack due to erosion damage during the plasma treatment process.

Accordingly, it is possible to increase the production yield of semiconductor chips or display devices manufactured from the substrate 10 processed by the plasma, and contribute to improving their quality.

On the other hand, since the reason for forming the surface supplementary layer 800 is to fill in the micro grooves 710 to supplement, the portion penetrated into the micro grooves 710 after forming the surface supplementary layer 800 A process of removing the remaining surface residue may be further performed. For example, the process of removing the surface residue may be performed through a polishing process. In this case, the surface melting layer 700 is exposed from the plasma in place of the surface supplementary layer 800.

Accordingly, since the surface melting layer 700 is formed through chemical bonding, and the surface supplementing layer 800 is formed through physical bonding, the surface melting layer 700 has better properties in terms of hardness and plasma resistance. However, in terms of corrosion resistance, since the surface supplementary layer 800 has more excellent characteristics, a process of removing the exposed portion of the surface supplementation layer 800 may be performed by dividing as necessary using such characteristics.

However, since the surface complementary layer 800 is basically superior in plasma resistance than the thermal spray coating layer 600, in the general plasma treatment process as described above, the polishing process is left as it is, and the inner wall 220 It is preferable to more securely protect the surface from the plasma, as in the surface melting layer 700.

In the detailed description of the present invention described above, it has been described with reference to preferred embodiments of the present invention, but those skilled in the art or those of ordinary skill in the art, the spirit of the present invention described in the claims to be described later. And it will be appreciated that various modifications and changes can be made to the present invention within a range not departing from the technical field.

As described above, in order to protect the interior of the vacuum chamber providing the plasma processing space from plasma, a surface melt layer formed by melting a thermal spray coating layer and a part of the surface of the thermal spray coating layer on the internal parts of the vacuum chamber may be formed. When the micro grooves due to thermal cracks that are inevitably formed on the surface melting layer are filled using an aerosol deposition method, impurities are prevented from being generated by the plasma from the micro grooves due to the thermal cracks. It can be actively used.

10: substrate 100: plasma processing apparatus
200: vacuum chamber 210: plasma processing space
220: inner wall 300: stage
400: plasma electrode 500: inner material
600: thermal spray coating layer 700: surface melting layer
710: fine groove 800: surface complementary layer

Claims (16)

Forming a thermal spray coating layer through a first ceramic material on an internal component of a vacuum chamber providing a plasma processing space;
Melting a part of the surface of the thermal spray coating layer to form a surface melting layer having a denser particle distribution than that of the thermal spray coating layer; And
Including the step of forming a surface supplementary layer on the surface melting layer using a second ceramic material,
The method of manufacturing an inner material for a plasma processing apparatus, further comprising the step of increasing an area ratio of the subsequently formed surface fusion layer by polishing the surface of the thermal spray coating layer before forming the surface fusion layer. The method of claim 1, wherein the second ceramic material has at least one component identical to that of the first ceramic material. The method of claim 1, wherein in the forming of the superficial melting layer, microgrooves are formed on the surface of the superficial melting layer,
In the forming of the surface supplementing layer, the surface supplementing layer is formed so that the second ceramic material is formed in the micro grooves. The method of claim 3, after forming the surface supplementary layer,
The method of manufacturing an inner material for a plasma processing apparatus, further comprising removing the remaining surface residues of the surface supplement layer except for portions formed in the fine grooves. The method of claim 1, wherein in the forming of the superficial melting layer, microgrooves are formed on the surface of the superficial melting layer,
In the step of forming the surface supplementation layer, forming the surface supplementation layer by using the aerosol deposition method by including ceramic particles having a size 10 times or less larger than that of the micro grooves in the second ceramic material. A method of manufacturing an inner material for a plasma processing apparatus, characterized in that. The method of claim 1, wherein in the forming of the surface supplementary layer, the surface supplementation layer is formed to a thickness of 5 to 10 μm. delete The method of claim 1, wherein in the polishing step, the thermal spray coating layer is polished so that the average roughness of the center line is 3 μm or less or the ten point average roughness is 20 μm or less. The method of claim 1, wherein in the forming of the thermal spray coating layer, the thermal spray coating layer is formed to a thickness of 50 to 300 μm. The method of claim 1, wherein in the forming of the surface melting layer, the surface melting layer is formed to a thickness of 10 to 30 μm. A thermal spray coating layer formed through a first ceramic material on an internal part of the vacuum chamber providing a plasma processing space;
A surface melting layer having a particle distribution denser than that of the thermal spray coating layer by melting a part of the surface of the thermal spray coating layer, and having fine grooves formed on the surface; And
A surface supplementary layer formed on the surface melting layer to penetrate into the microgrooves through a second ceramic material,
The inner material for a plasma processing apparatus, wherein the surface melting layer has an area ratio of 90% or more with respect to the total area of the thermal spray coating layer. The inner material of claim 11, wherein the second ceramic material has at least one component identical to that of the first ceramic material. The inner material for a plasma processing apparatus according to claim 11, wherein the surface supplement layer has a thickness of 5 to 10 μm. The inner material of claim 11, wherein the thermal spray coating layer has a thickness of 50 to 300 μm. The inner material for a plasma processing apparatus according to claim 11, wherein the molten surface layer has a thickness of 10 to 30 μm. The inner material for a plasma processing apparatus according to claim 11, wherein the surface complementary layer is formed limited to the micro grooves so that all portions of the surface melting layer except for the micro grooves are exposed.

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