Plasma-resistant two-layer coating film structure and its manufacturing method

Abstract

The present invention relates to a two-layer coating film structure formed on the surface of a ceramic or metal substrate to reduce etching by plasma, and a method for producing the same. The present invention provides a plasma-resistant two-layer coating film structure, comprising: a ceramic or metal substrate having pits on its surface; a first coating layer including a ceramic polycrystal having a crystallite size of less than 300 nm, the first coating layer being coated while filling the pits on the substrate surface, and having micro-pits formed on the surface by bonding of ceramic particles, the crystallite size being less than 300 nm; and a second coating layer being a plasma-resistant ceramic film coated on the first coating layer by any one of chemical vapor deposition (CVD), physical vapor deposition (PVD), and atomic layer deposition (ALD), the second coating layer being formed to have a surface roughness (Ra) of 0.2 μm or less without a separate grinding process, and being coated while covering the micro-pits, thereby forming a surface with minimized sites that may become starting points of plasma etching, the second coating layer being crystalline or having a mixture of crystalline and amorphous.

Description

[Technical Field]

[0001] The present invention relates to a two-layer coating film structure formed on the surface of a ceramic or metal substrate to reduce etching by plasma, and a method for manufacturing the same. [Background technology]

[0002] In general, it is known that etching of process parts exposed to plasma during semiconductor processing occurs preferentially in locally recessed portions (grooves; hereinafter referred to as pits) on the surface of the process part, and as etching progresses throughout the entire process part over time, the locally initiated etching spreads to the entire surface of the process part (Byung-Kuk Lee et al., Non-Patent Document 1).

[0003] In addition, a protective layer against plasma etching has been formed by coating the surfaces of process parts exposed to plasma during semiconductor processing with a plasma-resistant material (e.g., Y2O3, Junichi Iwasawa et al., Non-Patent Document 2).

[0004] One example of such a technology is disclosed in Korean Patent Registration No. 10-2213756 (Patent Document 1), which involves forming a plasma protective coating layer on the surface of a substrate (process part) using a thermal spray method. However, the coating layer formed by the thermal spray method inevitably contains cracks and pores, and has the drawback that plasma etching begins locally at the origin of these cracks and pores and spreads throughout the entire process part.

[0005] In addition, the technology described in Korean Patent Registration No. 10-0938474 (Patent Document 2) is a technology that realizes a protective layer against plasma etching by forming a crack-free and almost pore-free coating layer on the surface of process parts using the aerosol deposition (AD) method.

[0006] The technology described in Korean Patent Publication No. 10-2013-0044170 (Patent Document 3) is a technology that provides cross-shaped scratches having a depth of 1 to 2 μm on the surface of the aerosol deposition layer in addition to the technology described in Patent Document 2 that forms an aerosol deposition layer exposed to plasma.

[0007] Furthermore, the technology described in Korean Patent Registration No. 10-1563130 (Patent Document 4) is a technology that, in addition to the technology described in Patent Document 3, removes valleys and peaks on the surface of a process part, forms a coating film, and then removes the valleys and peaks on the surface of this coating film, resulting in a technology that exhibits even better plasma resistance than the technologies in Patent Documents 1, 2, and 3.

[0008] The coating films (layers) in the above Patent Documents 1 to 4 are commonly formed by applying a powder spray coating technique, with Patent Document 1 using a thermal spraying method, Patent Documents 2 and 3 using an aerosol deposition method, and Patent Document 4 using a spray coating method other than a thermal spraying method.

[0009] Meanwhile, coating methods other than thermal spraying for forming a plasma protective layer include ion-assisted deposition (IAD), plasma reactive deposition (PRD), plasma-enhanced CVD, plasma-enhanced evaporation, physical vapor deposition (PVD), and plasma immersion ion process (PIIP) technology (Korean Patent Registration No. 10-1309716, Patent Document 5). Other methods for forming a plasma protective layer include plasma-enhanced CVD (PECVD), physical vapor deposition (PVD), chemical vapor deposition (CVD), and atomic layer deposition (ALD) technology (Korean Patent Publication No. 10-2016-0143532, Patent Document 6).

[0010] The techniques of the above Patent Documents 1 to 6 have in common that a plasma protection layer made up of a single layer is formed on the surface of a process part that is exposed to plasma.

[0011] On the other hand, there is a technology in which an additional coating layer is formed between the surface of the process part exposed to plasma and the plasma protective layer.

[0012] The technology described in Korean Patent Registration No. 10-1108692 (Patent Document 7) is a technology that provides plasma resistance by forming the aerosol deposition layer of Patent Document 2 on the thermal spray coating layer of Patent Document 1. However, what sets this technology apart from other technologies is that the surface of the coating layer formed on the process part is processed using sandblasting to increase the roughness (average surface roughness of 0.4 to 2.3 μm) so that the aerosol deposition layer can adhere well to the thermal spray coating layer.

[0013] The technology described in Korean Patent Registration No. 10-2182690 (Patent Document 8) is a technology in which a thermal spray coating layer is formed on the surface of a process part exposed to plasma, a part of the surface of the thermal spray coating layer is melted to form a surface melted layer, and a surface complementing layer is formed on the melted layer by an aerosol deposition method.

[0014] The technology described in Korean Patent Registration No. 10-1817779 (Patent Document 9) is the same as Patent Document 7 in that it provides plasma resistance by forming the aerosol deposition layer of Patent Document 2 on the thermal spray coating layer of Patent Document 1. However, it differs from Patent Document 7 in that it includes a hydration treatment of the thermal spray coating layer and the aerosol deposition layer.

[0015] The technology described in Korean Patent Publication No. 10-2019-0057753 (Patent Document 10) is the same as Patent Document 7 in that it provides plasma resistance by forming the aerosol deposition layer of Patent Document 2 on the thermal spray coating layer of Patent Document 1, but differs from Patent Document 7 in that the surface of the thermal spray coating layer is polished.

[0016] As described above, Patent Documents 7 to 10 are all technologies that aim to reduce plasma etching that begins polarity-induced by forming an aerosol deposition layer (Patent Documents 2 and 3) that reduces pores and cracks in a thermal spray coating film (layer) (Patent Document 1) that has pores and cracks on the surface of a process part exposed to plasma. [Prior art documents] [Patent documents]

[0017] [Patent Document 1] Korean Patent Registration No. 10-2213756 [Patent Document 2] Korean Patent Registration No. 10-0938474 [Patent Document 3] Korean Patent Publication No. 10-2013-0044170 [Patent Document 4] Korean Patent Registration No. 10-1563130 [Patent Document 5] Korean Patent Registration No. 10-1309716 [Patent Document 6] Korean Patent Publication No. 10-2016-0143532 [Patent Document 7] Korean Patent Registration No. 10-1108692 [Patent Document 8] Korean Patent Registration No. 10-2182690 [Patent Document 9] Korean Patent No. 10-1817779 [Patent Document 10] Korean Patent Publication No. 10-2019-0057753 Summary of the Invention [Problem to be solved by the invention]

[0018] An object of the present invention is to provide a plasma-resistant two-layer coating film structure in which a first coating layer is formed on the surface of a ceramic substrate and a second coating layer is formed on the first coating layer, thereby significantly reducing plasma etching. [Means for solving the problem]

[0019] To achieve the above object, the present invention provides a plasma-resistant two-layer coating film structure comprising: a ceramic or metal substrate having pits on its surface; a first coating layer comprising a ceramic coating film formed on the surface of the substrate without cracks by a spray coating method other than thermal spraying, the first coating layer being coated while filling the pits on the surface of the substrate, and including ceramic polycrystalline bodies with a crystallite size of less than 300 nm, and the first coating layer being coated on the first coating layer by one of chemical vapor deposition (CVD), physical vapor deposition (PVD), and atomic layer deposition (ALD), the second coating layer being a plasma-resistant ceramic film formed to a surface roughness (Ra) of 0.2 μm or less without a separate grinding process, and coated while covering the micropits, thereby minimizing potential plasma etching starting points, and the second coating layer being crystalline or a mixture of crystalline and amorphous.

[0020] Semiconductor process parts may be employed as the substrate.

[0021] The first coating layer is formed from one or more of Al2O3, Y2O3, Tm2O3, Gd2O3, Dy2O3, Er2O3, and Sm2O3, and may be formed to have no cracks, a porosity of 1 vol% or less, and a thickness of 20 μm or less.

[0022] The second coating layer may be formed from a ceramic film containing yttrium (Y) or a ceramic film containing a metal oxide. Specifically, the second coating layer may be formed from one or more of Y2O3, YF3, YOF, YAG, YAP, and YAM, or one or more of Tm2O3, Gd2O3, Dy2O3, Er2O3, and Sm2O3, and may be formed to be pore-free and have a layer thickness of 15 μm or less. The second coating layer may be formed to have a surface hardness (Vickers shardness; Hv) of Hv 500 to Hv 1,500.

[0023] The present invention also provides a method for manufacturing a plasma-resistant two-layer coating film structure, including the steps of: (a) spraying ceramic powder onto a ceramic or metal substrate having pits on its surface using a spray coating method other than thermal spraying, thereby forming a first coating layer including a ceramic polycrystalline body with a crystallite size of less than 300 nm, the first coating layer being coated while filling the pits on the substrate surface and forming micro-pits on the surface due to the bonding of ceramic particles; and (b) forming a second coating layer on the first coating layer using one of chemical vapor deposition (CVD), physical vapor deposition (PVD), and atomic layer deposition (ALD), the second coating layer being a crystalline or mixed crystalline and amorphous ceramic film containing yttrium (Y) or a metal oxide, the second coating layer having a surface roughness (Ra) of 0.2 μm or less, the second coating layer being coated while covering the micro-pits, thereby forming a surface with minimized potential plasma etching starting points.

[0024] Before step (a), a step (a-0) of grinding the surface of the substrate may be further included, and in step (a-0), the surface of the substrate may be ground so that the surface roughness (Ra) is 0.2 μm or less.

[0025] A step (a-1) of grinding the surface of the first coating layer may be further included between the steps (a) and (b), and in the step (a-1), the surface of the first coating layer may be ground so that the surface roughness (Ra) is 0.2 μm or less.

[0026] After step (a-1), step (a-2) of increasing the thickness of the first coating layer and step (a-3) of grinding the surface of the first coating layer with the increased thickness may be further included. Similarly, in step (a-2), the thickness of the first coating layer may be increased by a spray coating method other than thermal spray. In step (a-3), the surface of the first coating layer with the increased thickness may be ground to a surface roughness (Ra) of 0.2 μm or less.

[0027] After the step (b), a step (c) of subjecting the two-layer coating film structure to a heat treatment may be further included. [Effects of the Invention]

[0028] According to the present invention, the following effects can be obtained by forming a plasma-resistant two-layer coating film structure on the surface of a ceramic or metal substrate.

[0029] 1. The plasma resistance of the substrate can be ensured by forming a first coating layer on the surface of a substrate on which pits ranging in size from several micrometers (μm) to several tens of micrometers are present, and then forming a second coating layer made of a plasma-resistant ceramic film on the first coating layer, which has relatively smaller micropits (starting points at which plasma etching can concentrate) than the pits on the surface of the substrate due to the ceramic coating, and which has no pits on which plasma etching can concentrate or has significantly reduced pits on which plasma etching can concentrate.

[0030] 2. Semiconductor process parts having a plasma-resistant two-layer coating film structure formed thereon can reduce particle adhesion in processes where plasma is applied.

[0031] 3. Through the aforementioned plasma etching and particle reduction, semiconductor manufacturing and processing processes can be performed continuously and stably, improving production yields.

[0032] 4. It can reduce the defective rate of products after manufacturing and processing of semiconductors, etc.

[0033] 5. Extended external cleaning intervals for replacement of ceramic or metal substrates. [Brief explanation of the drawings]

[0034] [Figure 1] 1 is a cross-sectional view of a plasma-resistant two-layer coating film structure according to the present invention. [Figure 2] FIG. 1 is a cross-sectional schematic diagram of a single-layer coating film formed along a pit present on the surface of a substrate by a conventional PVD, CVD, or ALD method. [Figure 3] 1A and 1B are cross-sectional schematic diagrams of a coating film of a conventional thermal spray coating layer and an aerosol deposition layer formed on the surface of a substrate by an aerosol deposition method. [Figure 4] FIG. 2 is a detailed schematic cross-sectional view of the plasma-resistant two-layer coating film structure according to the present invention. [Figure 5] 1 is a process flow diagram of a method for manufacturing a plasma-resistant two-layer coating film structure according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0035] a ceramic or metal substrate having pits on its surface; a first coating layer, which is a ceramic coating film formed on the surface of the substrate without cracks by a spray coating method other than thermal spraying, and which is coated while filling pits on the surface of the substrate, and which includes a ceramic polycrystalline body having a crystallite size of less than 300 nm and micro-pits formed on the surface due to bonding of ceramic particles; a second coating layer, which is a plasma-resistant ceramic film coated on the first coating layer by any one of chemical vapor deposition (CVD), physical vapor deposition (PVD), and atomic layer deposition (ALD), and is formed to have a surface roughness (Ra) of 0.2 μm or less without a separate grinding process, and is coated while covering the micro-pits, thereby forming a surface in which the number of areas that can become starting points for plasma etching is minimized, and is made of crystalline or a mixture of crystalline and amorphous materials; A plasma-resistant two-layer coating film structure.

[0036] The technical concept of the present invention can be clearly compared with the above-mentioned Patent Documents 1 to 10.

[0037] The aforementioned Patent Document 1 is a thermal spraying method, and the coating layer formed by this technique contains cracks and pores, which cause significant plasma etching due to the cracks and pores.

[0038] The aforementioned Patent Documents 2 to 4 attempt to achieve plasma resistance using a single layer of powder spray coating, rather than thermal spraying. While these technologies effectively eliminate pores and cracks in the coating layer, the bonding between powder particles during the coating process results in the formation of micropits on the surface. These micropits become weak points where plasma etching concentrates, increasing the width and depth of the pits from these points, affecting the substrate.

[0039] The aforementioned Patent Documents 5 and 6 are technologies for achieving plasma resistance by forming a single coating layer using a method other than powder spray coating. Although these technologies produce a dense coating, because the coating layer is formed as a thin film, it follows the shape of the pits on the substrate surface rather than filling them, and this morphological characteristic of the coating layer makes it vulnerable to plasma.

[0040] The aforementioned Patent Documents 7 to 10 attempt to achieve plasma resistance by using a double layer (thermal spray coating layer + aerosol coating layer) formed by powder spray coating. The surface of the aerosol coating layer, which forms the double coating layer, suffers from the problem of micro-pit generation explained in the aforementioned Patent Documents 2 to 4, and the thermal spray coating layer, which forms the single coating layer, inevitably has cracks and pores, so the single coating layer cannot adequately prevent plasma etching from spreading from the micro-pits formed on the surface of the double coating layer.

[0041] In contrast, in the plasma-resistant two-layer coating film structure of the present invention, the first coating layer is formed by powder spray coating, excluding thermal spray, and the second coating layer is formed by a method such as chemical vapor deposition (CVD), physical vapor deposition (PVD), or atomic layer deposition (ALD), which forms a coating layer that is relatively denser (e.g., atomic-level stacking) than the first coating layer.

[0042] In the present invention, even if there are relatively large pits on the surface of the substrate, ranging in size from several micrometers (μm) to several tens of micrometers, the first coating layer fills the pits on the surface of the substrate, and the minute pits formed on the surface of the first coating layer are covered by the densely coated second coating layer, thereby minimizing areas where plasma etching concentrates on the surface of the second coating layer, thereby achieving significantly better plasma etching resistance than conventional technologies (Patent Documents 1 to 10).

[0043] The present invention will now be described with reference to the accompanying drawings.

[0044] I. Plasma-resistant double-layer coating film structure The present invention provides a plasma-resistant two-layer coating film structure comprising: a ceramic or metal substrate having pits on its surface; a first coating layer comprising a ceramic coating film formed on the surface of the substrate without cracks by a spray coating method other than thermal spraying, the first coating layer being coated while filling the pits on the surface of the substrate, and including ceramic polycrystalline bodies with a crystallite size of less than 300 nm, and micro-pits formed on the surface due to bonding of ceramic particles; and a second coating layer comprising a crystalline or a mixture of crystalline and amorphous materials, the second coating layer being a plasma-resistant ceramic film coated on the first coating layer by one of chemical vapor deposition (CVD), physical vapor deposition (PVD), and atomic layer deposition (ALD), the second coating layer being formed to have a surface roughness (Ra) of 0.2 μm or less without a separate grinding process, and being coated while covering the micro-pits, thereby minimizing potential plasma etching starting points.

[0045] The plasma-resistant two-layer coating film structure of the present invention may be produced according to the method described below in "II. Method for producing plasma-resistant two-layer coating film structure."

[0046] The structure of the present invention, as shown in FIG. 1, comprises a first coating layer and a second coating layer laminated in sequence on a ceramic or metal substrate.

[0047] As shown in FIG. 1, the plasma-resistant two-layer coating film structure provided by the present invention is a coating film structure comprising a first coating layer formed on the surface of a ceramic or metal substrate and a second coating layer formed on the first coating layer.

[0048] 1. First coating layer The first coating layer is a ceramic film containing ceramic polycrystals with a crystallite size of less than 300 nm.

[0049] The fact that the first coating layer contains a ceramic polycrystalline material means that the first coating layer may be entirely formed from a polycrystalline material, or may contain a portion of amorphous material.

[0050] That is, when the first coating layer is formed using the powder spray coating method, powder particles collide with the substrate at high speed (or ultra-high speed), or when the powder particles collide with each other, they are crushed, losing their crystallinity and changing into an amorphous phase, which may result in the presence of some amorphous material between the crystals.

[0051] In addition, unlike a coating film formed by melting ceramic powder particles in a thermal spray coating method, the polycrystalline body of the first coating layer is characterized in that the ceramic powder particles are crushed by collisions with the substrate and between the particles, forming crystallites with a size of less than 300 nm.

[0052] The crystallite size of the polycrystalline body can be confirmed from a transmission electron microscopy (TEM) photograph, and the components of the ceramic film can be analyzed using an energy dispersive X-ray (EDX) analysis.

[0053] The first coating layer may be made of one or more of Al2O3, Y2O3, Tm2O3, Gd2O3, Dy2O3, Er2O3, and Sm2O3.

[0054] On the other hand, unlike the powder spray coating method, a ceramic film formed by physical vapor deposition (PVD), chemical vapor deposition (CVD), or atomic layer deposition (ALD) method is generally formed along pits on the surface of a substrate, as shown in FIG. 2.

[0055] However, the first coating layer is formed by filling pits on the surface of the substrate as shown in Figure 4. However, micro-pits may be formed on the surface of the first coating layer during the process of bonding ceramic powder particles to form the coating layer.

[0056] The first coating layer according to the present invention has a thickness of 20 μm or less. The thickness of the first coating layer can be confirmed using a scanning electron microscope (SEM) photograph.

[0057] Meanwhile, as shown in Figure 3, a thermal spray coating layer on the surface of a substrate inevitably has cracks due to the method of spray coating by melting powder, but the first coating layer on the surface of the substrate according to the present invention is characterized by being crack-free, unlike a thermal spray coating layer. The presence or absence of cracks in the coating layer can be confirmed using a scanning electron microscope (SEM) photograph.

[0058] Furthermore, the first coating layer is characterized by having porosity of 1 vol% or less. This means that there are no pores, or even if there are pores, they are 1 vol% or less. The presence or absence of pores in the first coating layer can be confirmed by SEM or TEM photographs.

[0059] 2. Second coating layer The second coating layer is a plasma-resistant ceramic film formed on the first coating layer, and may be made of a ceramic film containing yttrium (Y) or a ceramic film containing a metal oxide to ensure plasma resistance.

[0060] Ceramic films containing yttrium (Y) include Y2O3, YF3, yttrium oxyfluoride (YOF), and yttrium aluminum (YAG, Y3Al5O 12 ), yttrium aluminum perovskite (YAP, YAlO3), and yttrium aluminum monoclinic (YAM, Y4Al2O9).

[0061] The ceramic film containing a metal oxide may be formed from one or more of Tm2O3, Gd2O3, Dy2O3, Er2O3, and Sm2O3.

[0062] The second coating layer is either entirely crystalline or a mixture of crystalline and amorphous. When the ceramic film is formed by methods such as CVD, PVD, or ALD, a mixture of crystalline and amorphous phases can be observed. However, by subjecting such a film to heat treatment, it becomes an entirely crystalline film. The presence or absence of crystalline or a mixture of crystalline and amorphous phases in the ceramic film of the second coating layer can be confirmed by TEM photographs or selected area (electron) diffraction (SAD, SAED) patterns.

[0063] As described above, the first coating layer is coated while filling pits on the surface of the substrate, resulting in the formation of micro-pits on the surface. However, the micro-pits in the first coating layer are covered by the second coating layer, minimizing the areas that could become starting points for plasma etching, thereby improving plasma resistance.

[0064] The second coating layer is formed to a thickness of 15 μm or less, and has a surface hardness (Vickers shardness; Hv) of Hv 500 to Hv 1,500. The greater the surface hardness, the better the plasma resistance (plasma etching resistance). The second coating layer is characterized by having a surface roughness (Ra) of 0.2 μm or less.

[0065] II. Manufacturing method for plasma-resistant two-layer coating film structure The present invention also provides a method for manufacturing a plasma-resistant two-layer coating film structure, including the steps of: (a) spraying ceramic powder onto a ceramic or metal substrate having pits on its surface using a spray coating method other than thermal spraying, thereby forming a first coating layer including a ceramic polycrystalline body with a crystallite size of less than 300 nm, the first coating layer being coated while filling the pits on the substrate surface and forming micro-pits on the surface due to the bonding of ceramic particles; and (b) forming a second coating layer on the first coating layer using one of chemical vapor deposition (CVD), physical vapor deposition (PVD), and atomic layer deposition (ALD), the second coating layer being a crystalline or mixed crystalline and amorphous ceramic film containing yttrium (Y) or a metal oxide, the second coating layer having a surface roughness (Ra) of 0.2 μm or less, the second coating layer being coated while covering the micro-pits, thereby forming a surface with minimized potential plasma etching starting points.

[0066] In the above section "I. Plasma-resistant two-layer coating film structure," the characteristics of the plasma-resistant two-layer coating film structure provided by the present invention and the phenomena and effects exhibited by those characteristics were described. Below, a method for manufacturing the plasma-resistant two-layer coating film structure will be described.

[0067] The plasma-resistant two-layer coating film structure according to the present invention is manufactured by forming a first coating layer and a second coating layer according to the process sequence shown in FIG.

[0068] The step (a) is a step of spray coating a ceramic powder onto a ceramic or metal substrate to form a first coating layer. As mentioned above, the substrate can be a semiconductor processing component.

[0069] In the step (a), the first coating layer may be formed by applying a spray coating method (such as an ALD method) other than thermal spray.

[0070] Before the step (a), a step (a-0) of grinding the surface of the substrate may be further included to reduce the depth of the pits on the surface of the substrate, and in the step (a-0), the surface of the substrate may be ground so that the surface roughness (Ra) is 0.2 μm or less.

[0071] Step (a-1) of grinding the surface of the first coating layer may be further included between steps (a) and (b) to further reduce the depth and width of the micro-pits on the surface of the first coating layer. In step (a-1), the surface of the first coating layer may also be ground to a surface roughness (Ra) of 0.2 μm or less.

[0072] After step (a-1), step (a-2) of increasing the thickness of the first coating layer and step (a-3) of grinding the surface of the first coating layer with the increased thickness may be further included. Similarly, in step (a-2), the thickness of the first coating layer may be increased by a spray coating method other than thermal spraying, and in step (a-3), the surface of the first coating layer with the increased thickness may be ground to a surface roughness (Ra) of 0.2 μm or less to minimize the depth of micro-pits on the surface of the first coating layer with the increased thickness.

[0073] Step (b) is a step of forming a second coating layer made of a ceramic film containing yttrium (Y) or a ceramic film containing a metal oxide on the first coating layer by a spray coating method other than thermal spray coating.

[0074] In step (b), the second coating layer may be formed by any one of chemical vapor deposition (CVD), physical vapor deposition (PVD), and atomic layer deposition (ALD), and the second coating layer may be formed to have a surface roughness (Ra) of 0.2 μm or less without a separate grinding process.

[0075] By the step (b), the second coating layer can be formed to a thickness of 15 μm or less and a surface hardness (Vickers shardness; Hv) of Hv 500 to Hv 1,500. The greater the surface hardness, the more improved the plasma resistance (plasma etching resistance).

[0076] The present invention can be applied to various fields and can be modified and changed in various ways without departing from the spirit of the present invention, and therefore, the claims of the present invention are intended to cover all modifications and changes that fall within the true scope of the present invention. [Industrial Applicability]

[0077] The plasma-resistant two-layer coating film structure and its manufacturing method provided by the present invention are applicable to the semiconductor industry.

Claims

1. a ceramic or metal substrate having pits on its surface; a first coating layer, which is a ceramic coating film formed on the surface of the substrate without cracks by a spray coating method other than thermal spraying, and which is coated while filling pits on the surface of the substrate, and which includes ceramic polycrystalline bodies with a crystallite size of less than 300 nm, and has a thickness of 20 μm or less and a porosity of 1 vol % or less, and which is formed on the surface of the substrate while filling pits on the surface of the substrate by a spray coating method other than thermal spraying, and which has fine pits on the surface due to bonding of ceramic particles, and which has a thickness of 20 μm or less and a porosity of 1 vol % or less; a second coating layer, which is a plasma-resistant ceramic film coated on the first coating layer by any one of chemical vapor deposition (CVD), physical vapor deposition (PVD), and atomic layer deposition (ALD), and is formed to have a surface roughness (Ra) of 0.2 μm or less without a separate grinding process, and is coated while covering the micro-pits, thereby forming a surface in which areas that may become starting points for plasma etching are minimized, and is made of crystalline or a mixture of crystalline and amorphous materials, has a layer thickness of 15 μm or less, and has a surface hardness of Hv 500 to 1500; A plasma-resistant two-layer coating film structure comprising:

2. 2. The plasma-resistant two-layer coating film structure according to claim 1, wherein the substrate is a semiconductor processing part.

3. The first coating layer is Al ２ O ３ , Y ２ O ３ , Tm ２ O ３ , Gd ２ O ３ , Dy ２ O ３ , Er ２ O ３ , Sm ２ O ３ 2. The plasma-resistant two-layer coating film structure according to claim 1, which is formed from at least one of the following:

4. 2. The plasma-resistant two-layer coating film structure according to claim 1, wherein the first coating layer is free of cracks.

5. 2. The plasma-resistant two-layer coating film structure according to claim 1, wherein the second coating layer is a ceramic film containing yttrium (Y) or a ceramic film containing a metal oxide.

6. The second coating layer is Y ２ O ３ , Y.F. ３ 2. The plasma-resistant two-layer coating film structure according to claim 1, which is made of at least one of YOF, YAG, YAP, and YAM.

7. The second coating layer has a Tm ２ O ３ , Gd ２ O ３ , Dy ２ O ３ , Er ２ O ３ , Sm ２ O ３ 2. The plasma-resistant two-layer coating film structure according to claim 1, which is formed from at least one of the following:

8. 8. The plasma-resistant two-layer coating film structure according to claim 1, wherein the second coating layer is free of pores.

9. (a) spraying ceramic powder onto a ceramic or metal substrate having pits on its surface by a spray coating method other than thermal spraying, to coat the substrate while filling the pits on the substrate surface, and forming a first coating layer including ceramic polycrystalline bodies having a crystallite size of less than 300 nm, with a thickness of 20 μm or less, and with porosity of 1 vol % or less, and with micro-pits formed on the surface due to bonding of ceramic particles; (b) forming a second coating layer on the first coating layer by any one of chemical vapor deposition (CVD), physical vapor deposition (PVD), and atomic layer deposition (ALD) to form a surface that minimizes the areas that may become starting points for plasma etching, the second coating layer being crystalline or a mixture of crystalline and amorphous, and made of a ceramic film containing yttrium (Y) or a metal oxide, and having a surface roughness (Ra) of 0.2 μm or less without a separate grinding process, a layer thickness of 15 μm or less, and a surface hardness of Hv 500 to 1500; A method for producing a plasma-resistant two-layer coating film structure, comprising:

10. The method for manufacturing a plasma-resistant two-layer coating film structure according to claim 9, further comprising, before the step (a), a step (a-0) of grinding the surface of the substrate.

11. 11. The method for manufacturing a plasma-resistant two-layer coating film structure according to claim 10, wherein in the step (a-0), the surface of the substrate is ground so that the surface roughness (Ra) is 0.2 μm or less.

12. 10. The method for manufacturing a plasma-resistant two-layer coating film structure according to claim 9, further comprising a step (a-1) of grinding the surface of the first coating layer between the steps (a) and (b).

13. 13. The method for manufacturing a plasma-resistant two-layer coating film structure according to claim 12, wherein in the step (a-1), the surface of the first coating layer is ground so that the surface roughness (Ra) is 0.2 μm or less.

14. After the step (a-1), (a-2) increasing the thickness of the first coating layer by spraying ceramic powder using a spray coating method other than thermal spraying; Step (a-3) of grinding the surface of the first coating layer having an increased thickness; The method for manufacturing a plasma-resistant two-layer coating film structure according to claim 13, further comprising:

15. 15. The method for manufacturing a plasma-resistant two-layer coating film structure according to claim 14, wherein in step (a-3), the surface of the first coating layer having the increased thickness is ground to a surface roughness (Ra) of 0.2 μm or less.

16. The method for manufacturing a plasma-resistant two-layer coating film structure according to claim 9, further comprising a step (c) of subjecting the two-layer coating film structure to a heat treatment after the step (b).

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