CN112126960B

CN112126960B - Surface treatment method

Info

Publication number: CN112126960B
Application number: CN202010553842.5A
Authority: CN
Inventors: 稻吉荣; 石榑文昭; 佐藤洋志
Original assignee: Ulvac Inc; Ulvac Techno Ltd
Current assignee: Ulvac Inc; Ulvac Techno Ltd
Priority date: 2019-06-25
Filing date: 2020-06-17
Publication date: 2021-09-03
Anticipated expiration: 2040-06-17
Also published as: JP6789354B1; JP2021004386A; KR102356737B1; CN112126960A; KR20210000668A

Abstract

Provided is a surface treatment method capable of suppressing detachment of a film-forming material deposited on the surface of a member from the member. The surface treatment method comprises the following steps: roughening a metal surface (10F) of the member (10) by sandblasting; forming a porous oxide film on the roughened surface (10F) by anodic oxidation; and etching at least the oxide film with an etching solution.

Description

Surface treatment method

Technical Field

The present invention relates to a surface treatment method.

Background

Various vacuum processing apparatuses such as a sputtering apparatus, an etching apparatus, and an ashing apparatus are composed of a plurality of members having metal surfaces. The members constituting the vacuum processing apparatus include: a member for partitioning a processing space in which a processing object is processed in a vacuum processing apparatus, and other various members disposed in the processing space. The deposition of the film-forming material is caused by the deposition of the film-forming material on these members, which is generated in association with the process in the process space. The film forming material detached from the member becomes fine particles, and may adhere to the processing object or the member to contaminate the processing object. Therefore, for example, sandblasting and thermal spraying are performed on the surface of an adhesion-preventing plate provided in a sputtering apparatus (see, for example, patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2012 and 224921

Disclosure of Invention

Problems to be solved by the invention

However, in the surface treatment of the surface of a member applied to a vacuum processing apparatus, there is still room for study in order to suppress the release of a film-forming material deposited on the surface of the member.

The purpose of the present invention is to provide a surface treatment method capable of suppressing detachment of a film-forming material deposited on the surface of a member from the member.

Means for solving the problems

The surface treatment method of one embodiment includes: roughening a metallic surface of the member by sand blasting; forming a porous oxide film on the roughened surface by anodic oxidation; and etching at least the oxide film with an etching solution.

According to this method, the surface is roughened by the blasting treatment, and the scale film formed on the roughened surface is etched, whereby the surface roughness of the surface can be improved and the surface can be cleaned. This makes it difficult for the film-forming material deposited on the surface to be detached from the surface.

In the surface treatment method, the forming of the oxide film may include: forming the oxide film having a thickness of 1 to 20 [ mu ] m. According to this configuration, the reliability is improved in that the medium that is driven into the surface by the blast treatment and the dirt caused by the medium are included in the oxide film. Thus, the reliability of removing both the dielectric and the dirt from the surface is improved by etching the oxide film.

In the surface treatment method, the etching at least the oxide film may include: etching is performed so that the etching amount is larger than the thickness of the oxide film in the thickness direction of the oxide film.

According to this method, the oxide film formed on the surface is reliably removed, and therefore the medium taken into the oxide film and the dirt caused by the medium are also reliably removed from the surface along with the growth of the oxide film. This cleans the surface, and as a result, the film-forming material deposited on the surface can be more inhibited from coming off.

In the surface treatment method, the surface may be formed to have an arithmetic average roughness higher than an arithmetic average roughness of the surface roughened by the blasting by forming the oxide film and at least etching the oxide film, the arithmetic average roughness being a roughness measured in accordance with JIS B0601: 2013.

According to this method, a surface having an arithmetic average roughness Ra higher than that after the blast treatment can be obtained, whereby the stress in the film-formed material formed on the surface is further relaxed. As a result, the film-forming material deposited on the surface can be more inhibited from coming off the surface.

In the surface treatment method, the surface may be formed of any one of aluminum and an aluminum alloy. According to this configuration, since the surface contains aluminum, the oxide film formed on the surface is an oxide of aluminum. Since the bilin-pidwals ratio of the aluminum oxide is 1 or more and 2 or less, a denser film is formed on the surface than an oxide having a pilin-pidwals ratio of less than 1 or more than 2. This makes it easy to form the oxide film into a shape that follows the surface. Therefore, since the oxide film has a shape simulating the uneven shape of the surface, even if the oxide film is etched, the surface roughness of the surface is less likely to be reduced than the surface roughness of the surface roughened by the blast treatment. Thereby, a surface having high surface roughness caused by the blasting treatment can be obtained. As a result, the film-forming material deposited on the surface can be more inhibited from coming off.

Drawings

Fig. 1 is a process diagram for explaining a step of performing blasting on a surface of a member in one embodiment of a surface treatment method.

Fig. 2 is a process diagram for explaining a step of forming an oxide film on the surface of a member in the above embodiment.

Fig. 3 is a process diagram for explaining a step of etching the surface of the member in the above embodiment.

Fig. 4 is a process diagram for explaining a step of cleaning the surface of the member in the above embodiment.

Detailed Description

One embodiment of the surface treatment method is described with reference to fig. 1 to 4. The surface treatment method and examples are explained in order below.

[ surface treatment method ]

The surface treatment method is explained with reference to fig. 1 to 4.

The surface treatment method comprises the following steps: roughening a surface of the component; forming a porous oxide film; and etching the oxide film. Roughening a surface of a component includes: the metallic surface of the member is roughened by sand blasting. The forming of the porous oxide film includes: a porous oxide film is formed on the roughened surface by anodic oxidation. The etching the oxide film includes: at least the oxide film is etched by an etching solution.

According to such a surface treatment method, the surface is roughened by sandblasting, and the scale film formed on the roughened surface is etched, whereby the surface roughness of the surface can be improved and the surface can be cleaned. This makes it difficult for the film-forming material deposited on the surface to be detached from the surface. As a result, particles are less likely to be generated in the vacuum processing apparatus to which the member is applied. Hereinafter, the surface treatment method will be described in more detail with reference to the drawings.

As shown in fig. 1, in the surface treatment method, first, a member 10 having a metal surface 10F is prepared. In the member 10, at least the surface 10F may be made of metal, but the entire member 10 may be formed of metal. The surface 10F may be formed of aluminum or an aluminum alloy.

When the surface 10F contains aluminum, the oxide film formed on the surface 10F is an oxide of aluminum. Since the piling-Bedworth ratio (piling-Bedworth ratio) of the aluminum oxide is 1 or more and 2 or less, a denser film is formed on the surface 10F than an oxide having a piling-Bedworth ratio of less than 1 or more than 2. This facilitates formation of an oxide film having a shape conforming to the shape of the surface 10F. Therefore, since the oxide film has a shape that simulates the unevenness of the surface 10F, even if the oxide film is etched, the surface roughness of the surface 10F is less likely to be reduced than the surface roughness of the surface 10F roughened by the blast treatment. Thereby, the surface 10F having high surface roughness due to the blast treatment can be obtained. As a result, the film forming material deposited on the surface 10F can be more inhibited from coming off. In addition, the pilin-butterwals ratio in aluminum and aluminum oxides is 1.28.

The vacuum processing apparatus to which the member 10 is applied is an apparatus capable of depositing a film-forming material on the surface 10F of the member 10. The vacuum processing apparatus may be, for example, various film forming apparatuses, etching apparatuses, ashing apparatuses, and the like. The film forming apparatus may be, for example, a sputtering apparatus, a CVD apparatus, a vapor deposition apparatus, or the like.

The member 10 is used in various vacuum processing apparatuses described above. The member 10 may be a member disposed in a processing space partitioned by the vacuum processing apparatus, or may be a member for partitioning the processing space. The member disposed in the processing space may be, for example, an adhesion preventing plate for preventing the film forming material from scattering into the processing space, a tray for supporting a processing object of the vacuum processing apparatus, or the like. The member partitioning the processing space may be, for example, a member forming an inner wall of a vacuum chamber partitioning the processing space. That is, the member 10 may have a flat plate shape or a shape along a predetermined curved surface. The member 10 may be formed of one plate member, or may be a combination of a plurality of plate members.

Next, the surface 10F is roughened by performing blasting treatment on the surface 10F. The surface roughness of the roughened surface 10F is made higher than the surface roughness of the surface 10F before roughening by sandblasting. Can be identified by a method represented by JIS B0601: 2013 the surface roughness in the surface 10F of the member 10 is evaluated by the arithmetic average roughness Ra.

In the blasting process, the medium M ejected from the nozzle N of the blasting apparatus is caused to collide with the surface 10F of the member 10. Thereby, the surface 10F after the blast treatment is rougher than the surface 10F before the blast treatment. The material forming the medium M may be, for example, a metal oxide, a metal carbide, a silicon oxide, a silicon carbide, or the like. The material forming the medium M may be, for example, iron, alumina, zirconia, silica, silicon carbide, silica sand, or the like. The medium M is a microparticle formed of each material. The medium M may include two or more kinds of particles made of different materials.

The particle size of the medium M can be 50-300 (japanese particle size standard). In addition, the particle size of the medium M was measured by JIS Z0311: 2004. When blasting surface 10F with medium M, the vapor pressure at 330 ℃ may be 1.33X 10^-4Pa or less. Preferably, the vapor pressure curve of medium M is lower than the vapor pressure curve of zinc. In medium M, a medium prepared by JIS Z2244: the vickers hardness defined in 2009 may be 400 or more. This improves the reliability of the surface 10F having the desired arithmetic average roughness Ra.

The medium M used for the blast treatment is often repeatedly used for the purpose of improving the utilization efficiency of the medium M. That is, many blasting apparatuses used for blasting are circulation type blasting apparatuses that circulate the medium M in the blasting apparatus. For the following reason, grease is often adhered to the surface 10F made of metal to be subjected to the blast treatment. That is, in order to suppress the surface 10F from being deteriorated, for example, rusted, grease is often applied to the surface 10F after the member 10 is formed. Alternatively, in order to smooth the processing of the metal used to form the member 10, grease is often applied to a portion of the base material of the member 10 corresponding to the surface 10F. Such grease can adhere to the medium M as dirt during the blast treatment.

Therefore, the grease applied to the surface 10F adheres to the medium colliding with the surface 10F, whereby the medium M is contaminated with the grease. Further, the more the number of times the medium M collides with the member 10 increases, the more the amount of grease adhering to the medium M.

In addition, if the grease is applied to the surface 10F before roughening, the grease adhering to the surface 10F can be removed by wiping the grease, washing the surface 10F with water, or the like. However, unlike the grease applied to the surface 10F before roughening, the grease that is driven into the surface 10F together with the medium M by sandblasting is difficult to remove from the surface 10F of the member 10 by wiping or cleaning.

As shown in fig. 2, an oxide film 10OF is formed on the roughened surface 10F by anodic oxidation. In the anodic oxidation, the electrolytic solution EL filled in the 1 st treatment tank T1 is immersed in the cathode CD and the anode AD, and the power supply P is connected to the cathode CD and the anode AD. In the present embodiment, the member 10 in the electrolytic solution EL is supplied with current via the anode AD by supporting the member 10 with the jig ADa provided to the anode AD. In addition, the anode AD other than the member 10 may not be used in the anodic oxidation. In this case, the member 10 may be connected to the power source P as an anode.

When the member 10 is made OF aluminum or an aluminum alloy, the member 10 is immersed in sulfuric acid OF 10 mass% to 20 mass%, for example, to form the oxide film 10OF on the surface OF the member 10.

When the member 10 is made OF titanium and the oxide film 10OF having a thickness OF several hundred nm is formed on the member 10, the electrolyte EL listed below can be used. That is, the electrolyte EL may be an electrolyte obtained by dissolving at least one of borax, ammonium borate, ammonium phosphate, and ammonium succinate in a solution in which methanol, ethylene glycol, glycerol, and propionic acid are mixed. The electrolyte EL may be 10 mass% to 20 mass% of phosphoric acid. The electrolyte EL may be phosphoric acid to which dextrin is added. The electrolyte EL may be a mixed solution of sodium carbonate, boric acid, borax, and tartaric acid. Alternatively, the member 10 may be anodized using the 1 st electrolytic solution and then anodized using the 2 nd electrolytic solution. In this case, for example, the 1 st electrolytic solution is a mixed solution of 15 mass% sulfuric acid, 10 mass% phosphoric acid, and 20 mass% acetic acid. The 2 nd electrolytic solution was a 10 mass% phosphoric acid solution using glacial acetic acid.

When the member 10 is made OF titanium and an oxide film 10OF having a thickness OF several hundred μm is formed on the member 10, the electrolyte EL may be a mixed liquid OF phosphoric acid and sulfuric acid.

When the oxide film 10OF is formed, the oxide film 10OF having a thickness OF 1 μm to 20 μm can be formed. This improves the reliability OF the oxide film 10OF including the medium M that has been shot into the surface 10F by the blast treatment and the dirt (grease, etc.) caused by the medium M. That is, the medium M and the dirt are more likely to be located on the surface OF the oxide film 10OF than on the boundary between the oxide film 10OF and the member 10 on which the oxide film 10OF is formed. Thus, the reliability OF removing both the medium M and the dirt from the surface 10F is improved by etching the oxide film 10 OF.

When the oxide film 10OF is formed by the anodic oxidation, the oxide film 10OF is formed on both the inner side and the outer side OF the surface 10F OF the member 10 before the anodic oxidation. Therefore, for example, the medium M that is driven into the surface 10F by the blast treatment is likely to be located in the oxide film 10OF or on the surface OF the oxide film 10 OF. Further, the medium M that is driven inside the surface 10F by, for example, blast treatment is also likely to be included in the oxide film 10 OF. Therefore, if the oxide film 10OF formed by anodic oxidation is removed from the member 10, the member 10 having the medium M and the surface 10F from which dirt due to the medium M is removed can be obtained.

Further, as the oxide film 10OF grows on the surface 10F by the anodic oxidation, a force acts on the medium M striking the surface 10F in a direction to separate the medium M from the surface 10F. That is, the oxide film 10OF grows in the vicinity OF the interface between the medium M and the surface 10F, and the medium M penetrating the surface 10F is pushed out from the interface between the oxide film 10OF and the base (i.e., the main body) OF the member 10 as the oxide film 10OF grows, whereby the state in which the medium M penetrates the member 10 is released.

When the oxide film 10OF is formed between the medium M and the surface 10F in this way, the medium M is squeezed out, and the oxide film 10OF further grows in the portion where the medium M is squeezed out. Such an effect can be sufficiently obtained even if the thickness OF the oxide film 10OF is several hundred nm.

In addition, as described above, when the member 10 is made of aluminum or an aluminum alloy, the pilin-butterwals ratio of aluminum and aluminum oxide is 1.28. Therefore, a dense oxide film 10OF is formed, and as a result, the oxide film 10OF easily grows in a direction substantially perpendicular to the surface 10F OF the member 10. Thereby, the surface shape OF the oxide film 10OF follows the shape OF the roughened surface 10F.

As shown in fig. 3, the surface 10F on which the oxide film 10OF is formed is etched using an etching solution ET. In the present embodiment, the member 10 is immersed in the etching liquid ET filled in the No. 2 treatment tank T2, whereby the surface 10F of the member 10 is etched by the etching liquid ET.

In the case where at least the oxide film 10OF is etched, the etching amount may be larger than the thickness OF the oxide film 10OF in the thickness direction OF the oxide film 10 OF. Accordingly, the oxide film 10OF formed on the surface 10F is reliably removed, and therefore the medium M incorporated in the oxide film 10OF and the dirt caused by the medium M are also reliably removed from the surface 10F along with the growth OF the oxide film 10 OF. This cleans the surface 10F, and as a result, the film-forming material deposited on the surface 10F can be more inhibited from coming off.

As described above, unlike the grease applied to the surface 10F before roughening, the grease that is driven into the surface 10F together with the medium M by the blast treatment is difficult to remove from the surface 10F of the member 10 by wiping or cleaning. In this regard, since the oxide film 10OF formed on the surface 10F OF the member 10 is etched by the etching OF the surface 10F using the etching liquid ET, the medium M OF the member 10 and the grease OF the member 10 driven together with the medium M are also removed.

The etching solution ET may be, for example, an aqueous sodium hydroxide solution (NaOH), an aqueous potassium hydroxide solution (KOH), or sulfuric acid (H)₂SO₄) Hydrochloric acid (HCl), hydrofluoric acid (HF), nitric acid (HNO)₃) Or metaphosphoric acid (HPO)₃) And the like. The etching solution ET may contain only one of these solutions, or may contain two or more of them.

In the case where the member 10 is formed of an aluminum alloy, the following solutions can be used as the etching solution ET. The etching solution ET may be an aqueous sodium hydroxide solution, an aqueous potassium hydroxide solution, or sulfuric acid, or may be a mixed solution containing at least two of these solutions. The etching solution ET may be an aqueous solution of sodium hydroxide-potassium ferricyanide or a solution obtained by mixing zinc chloride with an aqueous solution of sodium hydroxide. In the case of etching the surface 10F of the member 10 by electrolytic etching, a solution in which sulfuric acid and phosphoric acid are mixed can be used as the etching solution ET.

When the member 10 is formed of titanium, the following solutions can be used as the etching solution ET. The etching solution ET may be a solution obtained by mixing an aqueous potassium hydroxide solution and hydrogen peroxide, a solution obtained by mixing ammonium bifluoride in ethanol, hydrofluoric acid, a mixture of hydrofluoric acid and an aqueous iron (III) nitrate solution, or hydrochloric acid. In the case where the surface 10F of the member 10 is etched by electrolytic etching, a mixed solution of ethylene glycol and an aqueous sodium chloride solution can be used as the etching solution ET.

In addition, in these etching solutions ET, it is preferable to use a solution other than the solution containing hydrofluoric acid and a solution other than the solution containing zinc. This can suppress the release of zinc in the vacuum processing apparatus to which the member 10 is applied when hydrofluoric acid is released into the vacuum processing apparatus or when the temperature in the vacuum processing apparatus is about 100 ℃.

By forming the oxide film 10OF and etching at least the oxide film 10OF, a film having a surface 10F roughened by sandblasting, which is a film having a thickness in accordance with JIS B0601: 2013, and a surface 10F having an arithmetic average roughness Ra with a high arithmetic average roughness Ra. According to the above configuration, the surface 10F having the arithmetic average roughness Ra higher than that after the blast processing can be obtained, and accordingly, the stress in the film formed on the surface 10F is further relaxed. As a result, the film-forming material deposited on the surface 10F can be more inhibited from being detached from the surface 10F.

As shown in fig. 4, the member 10 after etching is cleaned with a cleaning liquid C. In the present embodiment, the member 10 is immersed in the cleaning liquid C filled in the 3 rd treatment tank T3, whereby the surface 10F of the member 10 is cleaned with the cleaning liquid C. The cleaning liquid C may be, for example, pure water or ultrapure water. The temperature of the cleaning liquid C may be, for example, 10 ℃ or higher, or the cleaning liquid C may be boiled. By using pure water or ultrapure water as the cleaning liquid C, when the member 10 is applied to a vacuum processing apparatus, it is possible to suppress the substance that may be discharged into the vacuum processing apparatus from remaining on the surface 10F of the member 10.

[ examples ]

The examples are illustrated with reference to table 1.

Comparative example 1

A film having a diameter of 45mm and a thickness of 3mm was prepared as a film having a thickness defined by JIS H4000: 2014A 5052 made round plate of aluminum alloy. Prepared by JIS Z0311: the surface of the disk was roughened by dry blasting using 100 beads glass specified in 2004 as a medium. Next, the disk was immersed in ethanol filled in a beaker, and subjected to ultrasonic cleaning for 5 minutes. Ethanol was replaced every time such ultrasonic cleaning was performed, and 5 times of disk cleaning with ethanol was performed. Thus, a disk of comparative example 1 was obtained.

Comparative example 2

A film having a diameter of 45mm and a thickness of 3mm was prepared as a film formed of IJS H4000: 2014A 5052 made round plate of aluminum alloy. Prepared by JIS Z0311: the surface of the disk was roughened by dry blasting using 100 beads glass specified in 2004 as a medium. Subsequently, the disk was immersed in a 10 mass% aqueous solution of sodium hydroxide at 25 ℃ for 2 minutes to etch the surface of the disk. The etching amount of the disk plate in the thickness direction of the disk plate was about 1 μm. Then, the surface of the disk was washed with water, and the disk was immersed in pure water. Finally, the surface of the disk was rinsed with pure water, thereby obtaining a disk of comparative example 2.

Comparative example 3

A disk of comparative example 3 was obtained in the same manner as in comparative example 2, except that the time for immersing the disk in the aqueous sodium hydroxide solution was changed to 30 minutes, and the etching amount of the disk was changed to about 20 μm.

[ example 1]

In comparative example 2, an oxide film having a thickness of 1 μm was formed on the surface of the disk having the roughened surface using 15 mass% sulfuric acid before etching the surface of the disk. In comparative example 2, the disk of example 1 was obtained in the same manner as in comparative example 2, except that the time for immersing the disk in the aqueous sodium hydroxide solution was changed to 3 minutes, and the etching amount of the disk was changed to about 1.5 μm.

[ example 2]

The disk of example 2 was obtained in the same manner as in example 1 except that the oxide film having a thickness of 20 μm was formed in example 1 and the time for immersing the disk in the aqueous sodium hydroxide solution was changed to 32 minutes, whereby the etching amount of the disk was changed to about 22 μm.

[ evaluation method ]

[ arithmetic average roughness Ra ]

The surface of each disc was measured according to JIS B0601: 2013, and the arithmetic average roughness Ra is measured. The measurement results are shown in table 1 below.

[ maximum cross-sectional height of roughness Curve Rt ]

The surface of each disc was measured according to JIS B0601: 2013, and determining the maximum cross-sectional height Rt of the rough surface. The measurement results are shown in table 1 below.

[ amount of deposit ]

After the measurement of the arithmetic average roughness Ra and the measurement of the maximum cross-sectional height Rt of the roughness curve were completed, a titanium nitride film having a thickness of 500 μm was formed on the surface of each disk. Then, a rectangular tape having a transverse length of 1cm and a longitudinal length of 2cm was stuck to the surface of the titanium nitride film, and when the tape was peeled from the titanium nitride film, the amount of titanium nitride particles adhering to the sticking surface of the tape was visually observed. The amount of titanium nitride particles was evaluated by the following levels. The evaluation results are shown in table 1 below.

Titanium nitride particles were not visually confirmed

Titanium nitride particles hardly adhered

The amount of adhered delta titanium nitride particles is small

The amount of adhered x titanium nitride particles is large

[ TABLE 1]

	Ra(μm)	Rt(μm)	Amount of deposit
				Comparative example 1	3.35	20.9	×
Comparative example 2	3.10	19.4	△
				Comparative example 3	2.42	15.8	○
Example 1	3.42	19.6	○
				Example 2	3.37	19.6	◎

As shown in table 1, the following were confirmed: the arithmetic average roughness Ra of the surface of the disk was 3.35 μm in comparative example 1, 3.10 μm in comparative example 2, and 2.42 μm in comparative example 3. The following were confirmed: the arithmetic average roughness Ra of the surface of the disk was 3.42 μm in example 1 and 3.37 μm in example 2.

The following were confirmed: in the member of comparative example 1 in which etching was not performed among comparative examples 1 to 3, the arithmetic average roughness Ra was the highest. In addition, the following were confirmed: according to comparative example 1 and examples 1 and 2, a member having an arithmetic average roughness Ra higher than that of the roughened member can be obtained by etching the surface after the oxide film is formed.

In addition, the following were confirmed: according to comparative examples 1 and 2 and example 1, the surface of the member is etched after the oxide film is formed, whereby the decrease in the arithmetic mean roughness Ra can be suppressed by the etching. In addition, the following were confirmed: according to comparative examples 1 and 3 and example 2, the surface of the member was also etched after the oxide film was formed, whereby the decrease in the arithmetic mean roughness Ra could be suppressed by etching.

The following were confirmed: the maximum cross-sectional height Rt of the roughness curve of the surface of the disk was 20.9 μm in comparative example 1, 19.4 μm in comparative example 2, and 15.8 μm in comparative example 3. The following were confirmed: the maximum cross-sectional height Rt of the roughness curve of the surface of the circular plate was 19.6 μm in example 1 and 19.6 μm in example 2.

The following were confirmed: according to comparative examples 1 to 3 and examples 1 and 2, the maximum cross-sectional height Rt of the roughness curve can be suppressed from decreasing by etching the surface of the member, as with the arithmetic average roughness Ra, also in the maximum cross-sectional height Rt of the roughness curve.

From the measurement results of the arithmetic average roughness Ra and the maximum cross-sectional height Rt of the roughness curve, by etching the surface of the member after the oxide film is formed, it can be said that the surface shape obtained after the etching follows the shape when roughened by the blast treatment.

The following were confirmed: the amount of deposit was "x" in comparative example 1, "Δ" in comparative example 2, and "o" in comparative example 3. The following were confirmed: the amount of the deposit was "o" in example 1 and "excellent" in example 2. Thus, the following were confirmed: when the etching amount in the surface of the member is the same, the film-formed material formed on the surface is less likely to be detached in the case where the surface of the member is etched after the oxide film is formed, as compared with the case where the surface of the member is etched without forming the oxide film. The reason why the separation of the film-forming material can be suppressed by the formation of the oxide film is considered to be as follows.

A) The reason is that: the media driven into the member by the blasting and the dirt caused by the media are removed from the member together with the oxide film, thereby improving the cleanliness of the surface.

B) The reason is that: after etching, the surface roughness of the surface of the member is suppressed to be smaller than the surface roughness of the surface roughened by sandblasting.

As described above, according to one embodiment of the surface treatment method, the following effects can be obtained.

(1) The surface 10F is roughened by sandblasting, and the oxide film 10OF formed on the roughened surface 10F is etched, whereby the surface 10F can be cleaned while improving the surface roughness OF the surface 10F. This makes it difficult for the film-forming material deposited on the surface 10F to be detached from the surface.

(2) When the surface 10F contains aluminum, even if the oxide film 10OF is etched, the surface roughness OF the surface 10F is not easily smaller than the surface roughness OF the surface 10F roughened by the blast treatment. Thereby, the surface 10F having high surface roughness due to the blast treatment can be obtained. As a result, the film forming material deposited on the surface 10F can be more inhibited from coming off.

(3) When the oxide film 10O having a thickness OF 1 μ M to 20 μ M is formed, the reliability is improved in that the medium M that is driven into the surface 10F by the blast treatment and the dirt caused by the medium M are included in the oxide film 10 OF. Thus, the reliability OF removing both the medium M and the dirt from the surface 10F is improved by etching the oxide film 10 OF.

(4) Since the oxide film 10OF formed on the surface 10F is reliably removed, the medium M taken into the oxide film 10OF and the dirt caused by the medium M are also reliably removed from the surface 10F along with the growth OF the oxide film 10 OF. This cleans the surface 10F, and as a result, the film formation material deposited on the surface 10F can be further inhibited from coming off.

(5) The surface 10F having the arithmetic average roughness Ra further higher than that after the blast treatment can be obtained, whereby the stress in the film formed on the surface 10F is more relaxed. As a result, the film-forming material deposited on the surface 10F can be more inhibited from being detached from the surface 10F.

The above-described embodiment can be modified as follows.

[ surface ]

The surface 10F may be formed of a metal other than aluminum or an aluminum alloy. Even in this case, the effect (1) can be obtained by roughening the surface 10F, forming the oxide film 10OF on the roughened surface 10F, and etching the oxide film 10 OF.

The arithmetic average roughness Ra of the surface 10F after etching may be smaller than the arithmetic average roughness Ra of the surface 10F after blasting. Even in this case, the effect (1) can be obtained by roughening the surface 10F, forming the oxide film 10OF on the roughened surface 10F, and etching the oxide film 10 OF.

The etching amount OF the member 10 may be equal to or less than the thickness OF the oxide film 10 OF. Even in this case, by etching at least a part OF the oxide film 10OF formed on the member 10, it is possible to remove the medium M contained in the oxide film 10OF and the dirt caused by the medium M in a large amount while suppressing the decrease in the surface roughness OF the surface 10F. Therefore, the effect (1) can be obtained.

The thickness OF the oxide film 10OF may be less than 1 μm or not more than 20 μm. Even in this case, by forming the oxide film 10OF before etching the member 10, it is possible to remove the medium M contained in the oxide film 10OF and the dirt caused by the medium M while suppressing the decrease in the surface roughness OF the surface 10F. Therefore, the effect (1) can be obtained.

[ Sand blast treatment ]

The blast treatment of the surface 10F may be a wet blast treatment instead of a dry blast treatment.

[ etching ]

Instead of immersing the member 10 in the etching liquid ET, the etching liquid ET may be sprayed on the surface 10F of the member 10 by a sprayer to etch the surface 10F.

[ cleaning ]

Instead of immersing the member 10 in the cleaning liquid C, the cleaning liquid C may be sprayed on the surface 10F of the member 10 by a sprayer to clean the surface 10F.

[ description of reference ]

10: a member; 10F: a surface; 10 OF: an oxide film; AD: an anode; ADA: a jig; c: cleaning fluid; CD: a cathode; EL: an electrolyte; ET: etching solution; m: a medium; n: a nozzle; p: a power source; t1: a 1 st treatment tank; t2: a 2 nd treatment tank; t3: and (3) a treatment tank.

Claims

1. A surface treatment method comprising:

roughening a member having a metal surface and applied to a vacuum processing apparatus by performing blasting on the surface;

forming a porous oxide film on the roughened surface by anodic oxidation; and

etching at least the oxide film with an etching solution,

roughening the surface comprises: using a circulation type blasting apparatus for circulating a medium in the blasting apparatus,

etching at least the oxide film includes: etching is performed so that the etching amount is larger than the thickness of the oxide film in the thickness direction of the oxide film,

forming the oxide film and at least etching the oxide film to form the surface having an arithmetic average roughness higher than an arithmetic average roughness of the surface roughened by the blasting, the arithmetic average roughness being a roughness value represented by JIS B0601: 2013.

2. The surface treatment method according to claim 1,

the forming of the oxide film includes: forming the oxide film having a thickness of 1 to 20 [ mu ] m,

etching at least the oxide film includes: the thickness of the oxide film is 110% to 150% in the thickness direction of the oxide film.

3. The surface treatment method according to claim 1 or 2,

the surface is formed of any one of aluminum or an aluminum alloy.