JP2023079783A - Thermal spray member, semiconductor manufacturing apparatus component including the same, method for manufacturing thermal spray member and method for manufacturing semiconductor manufacturing apparatus component including thermal spray member - Google Patents

Abstract

To provide a thermal spray member capable of exhibiting sufficient adhesion force and insulation function even when the thickness of a zirconia thermal spray film is relatively thin compared with the surface roughness of the surface to be thermally sprayed of an aluminum base material.SOLUTION: A thermal spray member 1 includes an aluminum base material 10 and of yttrium containing zirconia spray film 12. In the cross section of the surface of the base material 10 orthogonal to an interface between a surface 100 to be thermally sprayed and the spray film 12, a distance between two parallel straight lines sandwiching the interface is 0.2 μm over a length of 10 μm or more.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a thermal spraying member, a semiconductor manufacturing apparatus component including the thermal spraying member, a method for manufacturing the thermal spraying member, and a method for manufacturing a semiconductor manufacturing device component including the thermal spraying member.

US Pat. No. 6,300,001 discloses a thermally sprayed composite coating formed on a metallic or non-metallic substrate. The thermally sprayed composite coating described in US Pat. No. 5,800,002 has a first ceramic material phase and a second ceramic material phase. The first ceramic material phase comprises a zirconia-based coating selected from zirconia, partial zirconia and full zirconia and is present in an amount sufficient to provide corrosion resistance to the ceramic composite coating. The second ceramic material phase is present in an amount sufficient to provide plasma erosion resistance to the ceramic composite coating.

Special table 2013-532770

In the thermal sprayed composite coating described in Patent Document 1, when the thermal sprayed composite coating is formed on the metal substrate, the surface of the metal substrate to be thermally sprayed is roughened, and the zirconia-based coating is formed thereon. In general, in order to form a thermally sprayed ceramic film such as a zirconia thermally sprayed film on a metal substrate, it is necessary to increase the surface roughness of the surface of the metal substrate to be thermally sprayed. This is because the molten particles are allowed to enter the narrow portion corresponding to the surface roughness of the metal substrate, and the molten particles entering the narrow portion are solidified, thereby fixing the thermal sprayed film to the surface to be thermally sprayed by the anchor effect. When the surface roughness of the surface of the metal substrate to be sprayed is small (for example, when the surface roughness Ra is 0.001 μm to 0.2 μm), the influence of the above-mentioned anchor effect is reduced, so the metal substrate is less likely to be subjected to thermal spraying. It was very difficult to directly form a zirconia sprayed film on the sprayed surface. Further, when the thickness of the thermal sprayed film is relatively small with respect to the surface roughness of the surface to be thermally sprayed of the metal substrate, the influence of the above-mentioned anchor effect is reduced, making it difficult to exhibit the function of the thermally sprayed film. One case was assumed.

The present invention has been made in view of such circumstances, and provides a thermal spray member including a zirconia thermal spray coating provided on a thermal spray surface of an aluminum or aluminum alloy substrate, wherein the thickness of the zirconia thermal spray coating is the aluminum substrate. It is an object of the present invention to provide a thermal spraying member capable of exhibiting sufficient adhesion and insulating function even when the thickness is relatively thin compared to the surface roughness of the surface to be thermally sprayed, and to provide a method for manufacturing the thermal spraying member.

According to an aspect of the present invention, a substrate of aluminum or an aluminum alloy;
a thermally sprayed film covering the surface to be thermally sprayed of the base material, the thermally sprayed film of yttrium-containing zirconia, which is zirconium oxide containing yttrium;
In the cross section of the surface of the substrate covered with the thermal sprayed film perpendicular to the interface between the thermal sprayed surface of the substrate and the thermal sprayed film, the distance between two parallel straight lines sandwiching the interface is When the flatness of the interface is
A thermal spray member is provided, wherein the interface has a flatness of 0.2 μm or less over a length of 10 μm or more.

In the above configuration, the thermal spray member includes an aluminum or aluminum alloy base material and a thermal spray film of yttrium-containing zirconia. In the cross section of the surface of the substrate perpendicular to the interface between the surface to be thermally sprayed and the thermal sprayed film, the distance (flatness H) between two parallel straight lines sandwiching the interface is 0.00 for a length of 10 μm or more. 2 μm or less. In the thermal sprayed member having the above structure, the interface between the surface to be thermally sprayed and the thermally sprayed film is smooth, and it is not necessary to provide an intermediate layer between the surface to be thermally sprayed and the thermally sprayed film. In addition, even when the thickness of the thermal sprayed film is relatively thin compared to the surface roughness of the thermally sprayed surface of the base material, sufficient adhesion and insulating function can be exhibited.

According to another aspect of the present invention, there is provided a method of manufacturing a thermal spray member, comprising:
The thermal spraying member comprises a substrate made of aluminum or an aluminum alloy, and a thermally sprayed film covering the surface of the substrate to be thermally sprayed, the thermally sprayed film being yttrium-containing zirconia, which is zirconium oxide containing yttrium.
The manufacturing method is
heating the substrate having a surface roughness Ra of 0.001 μm to 0.2 μm on the surface to be thermally sprayed;
A slurry (zirconia slurry) prepared from the yttrium-containing zirconia raw material powder having a median diameter in the range of 0.5 μm to 6 μm and an aqueous solvent is plasma sprayed onto the surface to be thermally sprayed of the base material to obtain a thickness and forming the sprayed film having a thickness of 3 μm to 350 μm.

In the above configuration, the thermal spray member includes an aluminum or aluminum alloy base material and a thermal spray film of yttrium-containing zirconia. By including the first step of heating the substrate whose surface roughness Ra on the surface to be sprayed is in the range of 0.001 μm to 0.2 μm, the surface to be sprayed of the thermal sprayed member can be made smooth. In addition, a slurry prepared from raw powder of yttrium-containing zirconia having a particle diameter D50 (median diameter) in the range of 0.5 μm to 6 μm and an aqueous solvent is plasma sprayed onto the surface of the substrate to be thermally sprayed. Thus, it has a second step of forming a sprayed film with a thickness of 3 μm to 350 μm. As a result, a thermally sprayed film of yttrium-containing zirconia can be formed on an aluminum substrate, and the interface of the thermally sprayed surface can be made smooth.

Here, the water contained in the slurry reacts with the aluminum contained in the base material in the first step and the second step to generate Al- or Al-O-bonds, which are contained in the yttrium-containing zirconia. It is considered that the yttrium-containing zirconia thermal spray film is formed by the chemical bonding of yttrium (Y) and the further bonding of O and Zr. Therefore, a thermally sprayed film of yttrium-containing zirconia can be formed even on a smooth substrate having a surface roughness Ra of 0.001 μm to 0.2 μm.

FIG. 1 is a schematic illustration of a thermal spray member 1. FIG. FIG. 2 is a schematic diagram for explaining the flatness H of the interface between the thermal sprayed surface 100 and the thermal sprayed film 12 of the thermal sprayed member 1. As shown in FIG. FIG. 3 is a flow chart showing a method for manufacturing the thermal spray member 1. As shown in FIG. FIG. 4 is a schematic diagram for explaining the first step. FIG. 5 is a schematic diagram for explaining the second step. FIG. 6 is an explanatory diagram for explaining an electrostatic chuck 300 as an example of a component of a semiconductor manufacturing apparatus.

A thermal spray member 1 will be described as an example of a thermal spray member according to an embodiment of the present invention. As shown in FIG. 1, the thermal spraying member 1 includes a plate-like base material 10 and a thermally sprayed film of zirconium oxide containing yttrium provided on a surface to be sprayed 100, which is one of the peripheral surfaces of the base material 10. 12. In the following description, yttrium-containing zirconium oxide is referred to as yttrium-containing zirconia or simply zirconia. In this embodiment, the base material 10 is a plate-like member made of aluminum or an aluminum alloy (Al alloy). Examples of Al alloys include 1000 series, 2000 series, 5000 series, and 6000 series. The surface roughness Ra of the thermal sprayed surface 100 is preferably 0.001 μm to 0.2 μm. Further, it is more preferable that the surface roughness Ra of the thermal sprayed surface 100 is 0.001 μm to 0.1 μm. The thickness of the sprayed film 12 is preferably 5 μm to 350 μm.

In the following description, the interface between the thermal sprayed surface 100 and the thermal sprayed film 12 is simply referred to as the interface. A space between the surface to be sprayed 100 and the thermal sprayed film 12 is defined as an interface between the surfaces of the surface to be sprayed 100 and the thermally sprayed film 12 . In this specification, the flatness of the interface is defined as the distance between two parallel straight lines sandwiching the interface in the cross section of the substrate 10 perpendicular to the interface. Here, "perpendicular" means that the normal direction of the thermal sprayed surface 100 and the normal direction of the cross section intersect at 90°±10° when the thermal sprayed surface 100 is a flat or curved surface. In the thermal spray member 1 of this embodiment, the interface flatness H (see FIG. 2) is 0.2 μm or less over a length of 10 μm or more.

Next, a method for manufacturing the thermal spray member 1 will be described with reference to FIGS. As shown in FIG. 3, a plate-like substrate 10 made of aluminum (Al) or an aluminum alloy is prepared (S11). As described above, Al alloys of 1000s, 2000s, 5000s, and 6000s can be used as Al alloys. At least one main surface of the plate-shaped base material 10 is the thermal spray surface 100 . The surface roughness Ra of the sprayed surface 100 is 0.001 μm to 0.2 μm. The sprayed surface 10 of the substrate 1 may be surface-treated so that the surface roughness Ra of the sprayed surface 100 is 0.001 μm to 0.2 μm. As the surface treatment, a roughening treatment such as sandblasting is not required, and grinding and then polishing are preferred.

Next, as a first step, an activation process is performed on the thermal sprayed surface 100 of the substrate 10 (S12). In the activation process, the substrate 10 is first heated. Specifically, as shown in FIG. 4, the first non-oxidizing gas is supplied from the first non-oxidizing gas supply device 211 to the first plasma spraying apparatus 210, and the first plasma spraying apparatus 210 Alternatively, the sprayed surface 100 of the substrate 10 is irradiated with the plasma P1 of the first non-oxidizing gas from the nozzles constituting this. Ar gas, _H2 gas, or _N2 gas, for example, can be used as the first non-oxidizing gas. Alternatively, a mixed gas of any combination of Ar gas, _H2 gas, and _N2 gas can be used as the first non-oxidizing gas.

By performing the activation treatment, the thermal sprayed surface 100 of the substrate 10 is activated. Activating the thermal spray surface 100 includes forming an oxide layer on the thermal spray surface 100 . In the activation process, instead of irradiating the first non-oxidizing plasma gas P1, the substrate 10 may be heated using a heating device such as a hot plate in an air atmosphere or a non-oxidizing atmosphere.

Next, as a second step, a thermally sprayed film 12 of yttrium-containing zirconia is formed on the thermally sprayed surface of the substrate 10 (S13). Specifically, first, raw material powder of zirconia (yttrium-containing zirconia) containing yttrium and having a particle diameter D50 (median diameter) of 0.5 μm to 6 μm and an aqueous solvent are adjusted to obtain a zirconia slurry ( Hereinafter, simply referred to as slurry) is prepared. As shown in FIG. 5, the produced slurry is supplied from the slurry supply device 222 to the second plasma spraying device 220 or the nozzles constituting this. The second non-oxidizing gas is supplied from the second non-oxidizing gas supply device 221 to the second plasma irradiation device 220, and the second plasma spraying device 220 or this The slurry is plasma-sprayed onto the thermal-sprayed surface 100 of the substrate 10 from the nozzles constituting the . Yttrium contained in the yttrium-containing zirconia is preferably 2 mol % to 8 mol % in terms of Y ₂ O ₃ .

The second non-oxidizing gas may be the same as or different from the first non-oxidizing gas. When a common plasma spray apparatus is used as first plasma spray apparatus 210 and second plasma spray apparatus 220, the first and second steps can be performed continuously without the need to transport substrate 10 in the common plasma spray apparatus. can be implemented. In this case, the manufacturing cost of the thermal spray member 1 can be reduced. The first plasma spray device 210 and the second plasma spray device 220 may be separate plasma spray devices.

As a result, as shown in FIG. 1, a thermally sprayed film 12 of yttrium-containing zirconia is formed so as to cover the surface 100 of the substrate 10 to be thermally sprayed. The thickness of the sprayed film 12 is preferably adjusted to 5 μm to 350 μm. If the thickness of the sprayed film 12 is less than 3 μm, the insulating properties of the sprayed film 12 may deteriorate. Further, if the thickness of the sprayed film 12 exceeds 350 μm, the internal stress of the sprayed film 12 increases, and there is a possibility that adhesion may be reduced or peeling may occur. The porosity of the sprayed film 12 is preferably adjusted to 0.1-5%.

Also, the second step may be repeated multiple times. For example, after the first sprayed film that covers the surface 100 of the substrate 10 is formed in the first second step, a second sprayed film that further covers the first sprayed film in the second second step. may be formed.

The present invention will be further described below using Examples 1 to 6. However, the present invention is not limited to the examples described below. Tables 1 and 2 shown below summarize the results of Examples 1 to 6 and Comparative Examples 1 to 5.

[Example 1]
<First step>
As the base material 10, a rectangular plate-like aluminum base material having a surface to be thermal sprayed 100 with a surface roughness Ra of 0.2 μm, length and width dimensions of 20 mm×30 mm, and a thickness of 3 mm was prepared. The thermal sprayed surface 100 was adjusted by polishing after grinding. By using the first plasma spraying device 210 (high-speed plasma spraying device), the plasma P1 of the first non-oxidizing gas was applied to the sprayed surface 100 of the substrate 10 (see FIG. 3). A mixed gas of Ar gas, _N2 gas and _H2 gas was used as the first non-oxidizing gas. The Ar gas supply rate to the nozzles constituting the thermal spraying apparatus was controlled at 100 l/min, the N ₂ gas supply rate was controlled at 70 l/min, and the H ₂ gas supply rate was controlled at 60 l/min.

By controlling the current applied to the nozzles constituting the first plasma spraying apparatus 210 to 250 A, the power supplied to the nozzles was adjusted to 65 kW. The distance between the tip of the nozzle and the thermal sprayed surface 100 of the substrate 10 was adjusted to 75 mm. The scanning speed or displacement speed of the nozzle relative to the substrate 10 was adjusted to 850 mm/s. Then, a plasma P1 of a mixed gas of Ar gas, N ₂ gas and H ₂ gas was generated, and the plasma P1 was irradiated or jetted from the tip of the nozzle onto the thermal sprayed surface 100 of the substrate 10 . As a result, the thermal sprayed surface 100 of the substrate 10 was activated (see FIG. 4).

<Second step>
The first plasma spraying device 210 was used as it was as the second plasma spraying device 220 . A slurry containing zirconia was plasma-sprayed onto the thermal-sprayed surface 100 of the substrate 10 using the plasma P2 of the second non-oxidizing gas (see FIG. 5). The slurry was prepared from 300 g of raw zirconia powder having a purity of 99.9% or higher, containing 3 mol % of yttrium in terms of Y ₂ O ₃ and having a particle diameter D50 (median diameter) of 3 μm, and 700 g of water. A mixed gas of Ar gas, _N2 gas and _H2 gas was used as the second non-oxidizing gas. The Ar gas supply rate to the nozzles constituting the second plasma spraying apparatus 220 is controlled to 100 l/min, the _N2 gas supply rate is controlled to 70 l/min, and the _H2 gas supply rate is controlled to 60 l/min. controlled. This controlled the thermal spraying speed to 600-700 mm/s.

By controlling the current applied to the nozzles constituting the second plasma spraying apparatus 220 to 250 A, the power supplied to the nozzles was adjusted to 65 kW. The distance between the tip of the nozzle and the thermal spray surface 100 of the substrate 10 was adjusted to 75 mm. The scanning speed or displacement speed of the nozzle relative to the substrate 10 was adjusted to 850 mm/s. Then, plasma P2 of mixed gas of Ar gas, N ₂ gas and H ₂ gas was generated, and the raw material powder melted by the plasma P2 was sprayed from the tip of the nozzle onto the thermal sprayed surface 100 of the substrate 10. . As a result, a sprayed film 12 having a thickness of 150 μm was formed on the sprayed surface 10 of the substrate 10 (see FIG. 1). Thus, the thermal spray member 1 of Example 1 was produced. The thickness of the sprayed film 12 was measured with an eddy current film thickness meter.

<Example 2>
A thermal spray member 1 of Example 2 was produced under the same conditions as in Example 1, except that the base material 10 having a thermal spray surface 100 with a surface roughness Ra of 0.005 μm was prepared.

<Example 3>
In the first step (see FIG. 3, S12), the surface 100 of the substrate 10 to be thermally sprayed is heated by being placed on a hot plate instead of being thermally sprayed with non-oxidizing gas plasma. A thermal spray member of Example 3 was made according to the same conditions as Example 1, except that it was activated.

<Example 4>
In the second step (see FIG. 3, S13), the zirconia raw material powder having a particle size D50 of 0.5 μm was used to prepare the slurry of Example 4 according to the same conditions as in Example 1. A thermal spray member was produced.

<Example 5>
In the second step (see FIG. 3, S13), the thermal spraying member of Example 5 was prepared under the same conditions as in Example 1, except that the zirconia raw material powder having a particle size D50 of 6 μm was used to prepare the slurry. was made.

<Example 6>
In the second step (see FIG. 3, S12), a thermal sprayed film 12 having a thickness of 3 μm was formed on the thermal sprayed surface 100 of the substrate 10 . A thermal sprayed member of Example 6 was produced under the same conditions as in Example 1 except for this.

<Example 7>
In the first step (see FIG. 3, S12), the thermal sprayed surface 100 of the substrate 10 is polished to prepare the substrate 10 having the thermal sprayed surface 100 with a surface roughness Ra of 0.2 μm. A thermal sprayed member of Example 7 was produced under the same conditions as in Example 1, except that the sprayed surface 100 was adjusted by grinding.

<Comparative Example 1>
In the first step (see FIG. 3, S12), the thermal spray surface 100 of the substrate 10 is sandblasted to prepare the substrate 10 having the thermal spray surface 100 with a surface roughness Ra of 2 μm. A sprayed member of Comparative Example 1 was produced under the same conditions as in Example 1, except for

<Comparative Example 2>
In the second step (see FIG. 3, S13), dry thermal spraying was employed instead of wet thermal spraying. Granules made of zirconia raw material with a particle diameter D50 of 30 μm were used, and a mixed gas of Ar gas, N ₂ gas and H ₂ gas was used as a carrier gas. The supply amount of Ar gas to the nozzles constituting the second plasma spraying apparatus 220 is controlled to 100 l/min, the supply amount of _N2 gas is controlled to 70 l/min, and the supply amount of _H2 gas is controlled to 70 l/min. controlled. This controlled the thermal spraying speed to 600-700 mm/s.

By controlling the current applied to the nozzles constituting the second plasma spraying apparatus 220 in the range of 100 to 110 A, the power supplied to the nozzles was adjusted to 50 to 60 kW. The distance between the tip of the nozzle and the thermal spray surface 10 of the substrate 1 was adjusted to 80 mm. The scanning speed or displacement speed of the nozzle relative to the substrate 1 was adjusted to fall within the range of 100-1000 mm/s.

A sprayed member of Comparative Example 2 was produced under the same conditions as in Example 1 except for these.

<Comparative Example 3>
In the second step (see FIG. 3, S13), a slurry was prepared using ethanol instead of water as the solvent. A sprayed member of Comparative Example 3 was produced under the same conditions as in Example 1 except for this.

<Comparative Example 4>
In the second step (see FIG. 3, S13), a thermal sprayed film 12 having a thickness of 400 μm was formed on the thermal sprayed surface 100 of the substrate 10 . A sprayed member of Comparative Example 4 was produced under the same conditions as in Example 1 except for this.

<Comparative Example 5>
The thermal sprayed member of Comparative Example 5 was prepared under the same conditions as in Example 1, except that in the second step (see FIG. 3, S13), zirconia raw material powder having a particle size D50 of 9 μm was used to prepare slurry. made.

In addition, in the column of substrate heating method in Table 1 shown below, "1" means plasma irradiation, and "2" means heating with a hot plate.

<Evaluation of presence or absence of peeling>
In the thermal sprayed members of Examples 1 to 7 and Comparative Examples 1 to 5, the presence or absence of separation of the thermal spray coating 12 from the base material 10 (and the presence or absence of formation of the thermal spray coating 12) was visually confirmed. As shown in Table 2, in the thermal sprayed members 1 of Examples 1 to 7, no peeling of the thermal sprayed film 12 was confirmed. Further, in the thermal sprayed members 1 of Comparative Examples 1 to 5, it was confirmed that the thermal sprayed film 12 was partially separated from the substrate 10, or that the thermal sprayed film 12 was cracked.

<Evaluation of electrical insulation>
In the withstand voltage test, a 15 × 10 mm Ag electrode was formed on the thermal spray film 12, and a voltage of AC 60 Hz (1000 V/mm ) was applied and evaluated for the presence or absence of breakdown. In Table 2, ◯ indicates that 1000 V/mm or more was secured, and x indicates that breakdown occurred at less than 1000 V/mm. As shown in Table 2, no breakdown occurred in thermal spray member 1 of Examples 1-7. On the other hand, in the thermal sprayed members 1 of Comparative Examples 1 to 5, occurrence of breakdown was confirmed.

<Measurement of peel strength>
In the thermal sprayed members of Examples 1-7 and Comparative Examples 1-5, the peel strength of the thermally sprayed film 12 from the substrate 10 was measured. In the peel strength test, a disc-shaped metal plate with a diameter of 15 mm was adhered to the thermal spray film 12 with an organic adhesive, and the strength when the adhered metal plate was lifted vertically after fixing the periphery of the thermal sprayed member and peeled was measured. It was measured. As shown in Table 2, it was found that the thermal sprayed members 1 of Examples 1 to 7 all had a peel strength of 100 MPa or more. On the other hand, it was found that the thermal sprayed member 1 of Comparative Examples 1 to 5 had a peel strength of less than 100 MPa (a peel strength of 65 MPa or less).

<Measurement of Flatness H>
In the thermal sprayed members of Examples 1 to 7 and Comparative Examples 1 to 5, the flatness H of the interface between the substrate 10 and the thermal sprayed film 12 was measured. In the SEM cross-sectional image at 5000 times, the distance between two parallel straight lines across the interface is 0.2 μm or less over a length of 10 μm or more, and is marked as ×. bottom. As shown in Table 2, in each of the thermal sprayed members 1 of Examples 1 to 6, the flatness H was found to be 0.2 μm or less over a length of 10 μm or more. On the other hand, in the thermal sprayed members 1 of Comparative Examples 1 to 5, it was found that the flatness H exceeded 0.2 μm over a length of 10 μm or more.

From the above results, it was found that the thermal sprayed films 12 of Examples 1-7 are superior in adhesion to the substrate 10 than the thermally sprayed films 12 of Comparative Examples 1-5. It was found that the thermal sprayed films 12 of Examples 1-7 are superior to the thermally sprayed films 12 of Comparative Examples 1-5 in withstand voltage. It was found that the thermal sprayed films 12 of Examples 1-7 are superior in peeling resistance to the thermally sprayed films 12 of Comparative Examples 1-5. The interface between the substrate 10 and the thermal sprayed film 12 in the thermally sprayed films 12 of Examples 1 to 7 has smaller unevenness and flatness than the interface between the substrate 10 and the thermally sprayed film 12 in the thermally sprayed films 12 of Comparative Examples 1 to 5. H was found to be small. As shown in Examples 1 to 7, it was confirmed that the present invention can produce a thermal sprayed member having good adhesion and insulation even if the surface roughness of the substrate is small. In particular, in Example 2, even if the surface roughness of the base material is very small, a thermal sprayed member with high flatness can be produced, and it was found that the method can be applied to thermal sprayed members with high surface accuracy. Moreover, in Example 6, it was confirmed that even if the thickness of the sprayed film is as small as 3 μm, a sprayed member having good adhesion and insulation can be obtained because the surface roughness of the substrate is small.

In Comparative Example 1, the surface roughness Ra of the thermal sprayed surface 100 of the substrate 10 is excessively large in view of the grain size of zirconia. Therefore, it is presumed that the anchoring effect of the thermal spray coating 12 to the base material 10 due to penetration of the molten particles of zirconia into the narrow portion of the fine structure of the surface to be thermal sprayed 100 was not sufficiently exhibited. In addition, it is presumed that the surface roughness Ra of the thermal sprayed surface 100 was excessively large, resulting in the flatness H exceeding 0.2 μm.

In Comparative Example 2, the grain size of zirconia is excessively larger than the surface roughness Ra of the thermal sprayed surface 100 of the substrate 10 . Therefore, it is presumed that the anchoring effect of the thermal spray coating 12 to the base material 10 due to penetration of the molten particles of zirconia into the narrow portion of the fine structure of the surface to be thermal sprayed 100 was not sufficiently exhibited. In addition, it is presumed that since the fused particles of zirconia could not penetrate into the narrow part in the fine structure of the surface to be thermal sprayed 100, partial exfoliation occurred at the interface, and the flatness H became larger than 0.2 μm.

In Comparative Example 3, ethanol, which is the solvent for the slurry, has poor reactivity with the aluminum substrate, so it is speculated that the chemical bond described below did not develop, and the adhesion between the substrate 10 and the sprayed film 12 did not develop. be done. As a result, it is presumed that partial peeling occurred at the interface and the flatness H became larger than 0.2 μm.

In Comparative Example 4, since the thermal spray film 12 was excessively thick, the film stress was not relieved, and the thermal stress derived from the difference in thermal expansion coefficient with the substrate 10 was applied to the interface between the thermal spray film 12 and the substrate 10 (coating It is presumed that the delamination was concentrated on the sprayed surface 100). As a result, it is presumed that partial peeling occurred at the interface and the flatness H became larger than 0.2 μm.

In Comparative Example 5, it is presumed that a fluid slurry could not be prepared because the particle size of the yttrium oxide raw material powder was too large. As a result, the thermal spray coating is not sufficiently formed on the thermal spray surface 100, resulting in a structure in which the fused particles of zirconia cannot penetrate into narrow portions in the fine structure, causing partial exfoliation at the interface and reducing the flatness H. It is presumed that it became larger than 0.2 μm.

<Action and effect of the embodiment>

The thermal sprayed member 1 of Examples 1 to 7 includes an aluminum substrate 10 and a thermally sprayed film 12 of yttrium-containing zirconia. The thermal spray surface 100 of the thermal spray member 1 is made smooth by having the first step of heating the substrate 10 in which the surface roughness Ra of the thermal spray surface 100 is in the range of 0.001 μm to 0.2 μm. be able to. In addition, a slurry prepared from a raw powder of yttrium-containing zirconia having a particle diameter D50 (median diameter) in the range of 0.5 μm to 6 μm and an aqueous solvent is applied to the surface 100 of the substrate 10 to be sprayed by plasma. It has a second step of forming a sprayed film having a thickness of 3 μm to 350 μm by spraying. As a result, a thermally sprayed film of yttrium-containing zirconia can be formed on the aluminum substrate 10, and the interface of the thermally sprayed surface can be made smooth.

Here, the moisture contained in the slurry reacts with the aluminum substrate 10 in the first step and the second step to generate Al- or Al-O-bonds, and yttrium (Y) contained in zirconia. is chemically bonded, and then O and Zr are further bonded to form a zirconia sprayed film. Therefore, it is presumed that a zirconia sprayed film could be formed even on a smooth aluminum substrate 10 having a surface roughness Ra of 0.001 μm to 0.2 μm, for example. .

In the conventional method of forming a zirconia thermal spray film, as described above, molten particles enter a narrow space corresponding to the surface roughness of the base material, and the entering molten particles solidify and deposit due to the anchor effect. It used a mechanism to On the other hand, in the present invention, the surface to be sprayed 100 of the substrate 10 is irradiated with non-oxidizing gas plasma, or the substrate 10 is heated with a hot plate, so that the surface to be sprayed of the substrate 10 is 100 is heated and activated. After that, a slurry containing a water-based solvent is plasma-sprayed, whereby a chemical reaction acts at the boundary (interface) between the aluminum substrate 10 and the zirconia spray film 12, and zirconia is spray-sprayed onto the aluminum surface. It was presumed that the main effect of film formation was that the film was strongly bonded and formed. It is presumed that yttrium contained in zirconia contributes to this chemical reaction. Further, even if the boundary is magnified in a field of view of ×100000 times and observed with an SEM, it cannot be clearly determined. Therefore, it is presumed that film formation by such chemical bonding is the main film formation mechanism.

As described above, the thermal sprayed member 1 of Examples 1 to 7 includes the aluminum substrate 10 and the yttrium-containing zirconia thermally sprayed film 12 . In the cross section of the substrate 10 perpendicular to the interface between the surface 100 to be thermally sprayed and the thermal spray film 12, the distance between two parallel straight lines sandwiching the interface is 0.2 μm or less over a length of 10 μm or more. . Thus, in the thermal spray member 1 , the interface between the thermal spray surface 100 and the thermal spray coating 12 is smooth, and it is not necessary to provide an intermediate layer between the thermal spray surface 100 and the thermal spray coating 12 . Moreover, even when the thickness of the sprayed film 12 is relatively thin compared to the surface roughness of the sprayed surface 100 of the base material 10, sufficient adhesion and insulating function can be exhibited.

<Change form>
The above-described embodiment and Examples 1 to 7 are merely examples, and can be changed as appropriate. For example, the shape and dimensions of the substrate 10 are not limited to those of Examples 1 to 7, and may be changed as appropriate. Further, in the first step of Examples 1, 2, 4, 6 and 7, the plasma P1 of the first non-oxidizing gas and the plasma P2 of the second non-oxidizing gas are applied to the thermal sprayed surface 100 of the substrate 10. was irradiating. The present invention is not limited to such an aspect, and the gas for generating plasma can be changed as appropriate.

In the above embodiment and Examples 1 to 7, as the thermal spray member 1, a member in which the yttrium-containing zirconium thermal spray film 12 is formed on the thermal spray surface 100 of the plate-shaped base material 10 is described as an example. The thermal spraying member of the present invention is not limited to such members. For example, the thermal spraying member according to the present invention may be used as a thermal spraying member included in semiconductor manufacturing equipment components. For example, the thermal spraying member according to the present invention may be used for an electrostatic chuck as a component of semiconductor manufacturing equipment. As shown in FIG. 6, the electrostatic chuck 300 includes a base material 10 made of an aluminum alloy as a thermal spraying member 1, and a thermally sprayed film 12 having a thickness of 30 μm thermally sprayed on the surface of the base material 10 to be thermally sprayed. ing. In this electrostatic chuck 300, the substrate 10 is used as an electrode for high frequency power or as a DC electrode. As a result, the electrostatic chuck 300 can generate a potential difference with a substrate such as a silicon wafer placed on the thermal spray film 12 to electrostatically attract the substrate such as a silicon wafer. When manufacturing the electrostatic chuck 300, the thermal spraying member 1 can be manufactured by the manufacturing method described above.

Although the embodiments of the invention and their modifications have been described above, the technical scope of the invention is not limited to the scope of the above description. It will be apparent to those skilled in the art that various modifications or improvements may be made to the above embodiments. It is also clear from the description of the scope of claims that forms with such modifications or improvements can also be included in the technical scope of the present invention.

The execution order of each process in the manufacturing method shown in the specification and drawings is not specified in particular, and unless the output of the previous process is used in the subsequent process, in any order can be executed. For the sake of convenience, "first", "next", etc. are used for explanation, but it does not mean that it is essential to carry out in this order.

REFERENCE SIGNS LIST 1 thermal spraying member 10 base material 12 thermal spraying film 100 surface to be thermally sprayed 210 first plasma thermal spraying apparatus
211 first non-oxidizing gas supply device 220 second plasma spraying device 221 second non-oxidizing gas supply device 222 slurry supply device 300 electrostatic chuck

Claims (4)

a substrate of aluminum or an aluminum alloy;
a thermally sprayed film covering the surface to be thermally sprayed of the base material, the thermally sprayed film of yttrium-containing zirconia, which is zirconium oxide containing yttrium;
In the cross section of the surface of the substrate covered with the thermal sprayed film perpendicular to the interface between the thermal sprayed surface of the substrate and the thermal sprayed film, the distance between two parallel straight lines sandwiching the interface is When the flatness of the interface is H,
A thermal spray member, wherein the interface has a flatness H of 0.2 μm or less over a length of 10 μm or more. A semiconductor manufacturing equipment component comprising the thermal spraying member according to claim 1 . A method for manufacturing a thermal spray member,
The thermal spraying member comprises a substrate made of aluminum or an aluminum alloy, and a thermally sprayed film covering the surface of the substrate to be thermally sprayed, the thermally sprayed film being yttrium-containing zirconia, which is zirconium oxide containing yttrium.
The manufacturing method is
heating the substrate having a surface roughness Ra of 0.001 μm to 0.2 μm on the surface to be thermally sprayed;
A slurry prepared from the yttrium-containing zirconia raw material powder having a median diameter in the range of 0.5 μm to 6 μm and an aqueous solvent is plasma sprayed onto the surface to be thermally sprayed of the base material to a thickness of 3 μm to 350 μm. A method of manufacturing a thermal spray member, comprising: forming the thermal spray film. A method of manufacturing a semiconductor manufacturing equipment component comprising a base plate, comprising:
The base plate is a thermal spray member,
A method of manufacturing a component of a semiconductor manufacturing apparatus, wherein the manufacturing method includes manufacturing a thermal sprayed member as the base plate by the thermal sprayed member manufacturing method according to claim 3 .

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