JP4694771B2 - Pump and pump member manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an exhaust pump, and more particularly, to a vacuum pump used in a vacuum processing system and a manufacturing method thereof.
[0002]
[Prior art]
Generally, vacuum processing systems used for manufacturing semiconductor devices and the like include a cluster type system and an inline type system, and each of these systems includes a plurality of chambers and a member to be processed (wafer, glass substrate). It has a moving mechanism to transfer. In these vacuum processing systems, various processing such as formation of various films and etching are performed on a member to be processed in a state where each chamber is lower than atmospheric pressure (that is, in a vacuum state). In this relation, each chamber constituting the vacuum processing system is provided with a plurality of vacuum pumps for exhausting the inside of the chamber. In addition, the vacuum processing system becomes larger as a member to be processed such as a wafer and a glass substrate becomes larger, and the weight tends to become so heavy that it cannot be carried by a normal transportation means.
[0003]
Recently, a plasma processing system that performs plasma oxidation or oxygen radical oxidation in a specific chamber has been proposed, and a cluster type vacuum processing system is used for the plasma processing system. In such a plasma processing system, the gas to be exhausted is very reactive, so the vacuum pump itself needs to be made of a material that is not corroded by the reactive medium.
[0004]
In this type of processing system, various pumps such as a turbo molecular pump, a cryopump, a booster pump, a dry pump, and a scroll pump are used as an exhaust vacuum pump. These vacuum pumps include vacuum pump members such as rotors, blades, shafts, gears and the like housed in a casing having a suction port and a discharge port.
[0005]
Normally, the vacuum pump member constituting the vacuum pump is made of aluminum alloy such as duralumin or stainless steel, but aluminum alloy is preferable in terms of weight reduction of the vacuum pump.
[0006]
However, when a vacuum pump formed of an aluminum alloy is used as a vacuum pump of a plasma processing system, the inner wall of the vacuum pump is affected by a medium such as active species such as ions and corrosive gas when various gases are dissociated by plasma. Due to corrosion, vacuum pumps formed from aluminum alloys cannot be used in plasma processing systems. On the other hand, a vacuum pump formed of stainless steel cannot provide sufficient corrosion resistance against a medium such as active species. These problems are not limited to the vacuum pumps of the plasma processing system, but are generally applicable to pumps that discharge corrosive media.
[0007]
Further, the anodizing treatment disclosed in Patent Document 1 is applied to a vacuum pump to form a corrosion-resistant alumina film (Al ₂ O ₃ ) on the surface of a member formed of aluminum or an aluminum alloy. Proposed.
[0008]
In fact, Patent Document 2 describes a cryopump provided with an anodized cryopanel.
[0009]
[Patent Document 1]
Japanese Patent Laid-Open No. 7-216589
[Patent Document 2]
Japanese Patent Laid-Open No. 2003-21062
[Problems to be solved by the invention]
However, the Al ₂ O ₃ film formed by anodization is basically a porous film, and the surface is uneven. For this reason, the corrosion resistance of the anodized Al ₂ O ₃ film is very low against a highly reactive gas or chemical such as Cl-based gas, F-based gas, HCl, H ₂ SO ₄ , and HF.
[0012]
In addition, post-treatment such as applying high temperature water vapor to the anodized Al ₂ O ₃ film to absorb moisture into the film molecules to expand and fill the voids is also performed.
[0013]
However, if an anodized aluminum alloy is used for the gas exhaust vacuum pump member for a plasma apparatus, which is generally subjected to processing at a high degree of decompression even after the above-described post-treatment, a predetermined degree of decompression is used. It takes a very long time to reach
[0014]
This is because the oxide film on the surface of the anodized aluminum alloy is essentially porous, so that the vacuum is reduced to a predetermined degree of vacuum due to outgassing problems and the presence of voids remaining in the film. This is because it takes more time than necessary to pull.
[0015]
In addition, when electroless nickel plating is applied to an aluminum alloy, nickel serves as a catalyst. For example, SiH ₄ , B ₂ H ₆ , PH ₃ , AsH ₃ , and ClF ₃ gases are decomposed to generate corrosive gases and products. Promote.
[0016]
This invention is made | formed in view of this point, The objective is to provide the vacuum pump which can be used with respect to corrosive gas in a vacuum processing system.
[0017]
Another object of the present invention is to provide a vacuum pump that is small and lightweight.
[0018]
Still another object of the present invention is to provide a pump having high corrosion resistance against a highly reactive gas or chemical solution.
[0019]
[Means for Solving the Problems]
The pump of the present invention is characterized in that the portion exposed to the medium to be discharged is made of aluminum or an aluminum alloy and has an oxide film oxidized by plasma treatment.
[0020]
As an example of the oxide film oxidized by the plasma treatment, an oxide film oxidized by oxygen radicals generated by plasma can be given as an example.
[0021]
According to the study by the present inventors, an oxide film formed on the surface of aluminum or an aluminum alloy by plasma treatment, for example, oxygen radicals generated by plasma has a very dense and flat surface property. Moreover, it was confirmed that there were almost no voids in the film. It was also found that the oxide film was strong and improved in corrosion resistance.
[0022]
Therefore, by using a member having such a coating as a pump, in particular, as a pump member that comes into contact with a highly reactive medium, the time required for evacuation to a predetermined degree of decompression can be shortened compared to the conventional case, and the corrosion resistance. Was also found to improve. As will be described later, the oxidation with oxygen radicals is performed, for example, by converting the oxygen-containing gas into plasma and treating the surface of the aluminum or aluminum alloy with the plasma.
[0023]
Further, the pump member of the present invention may be made of aluminum or an aluminum alloy, and the surface of the vacuum pump member may have an oxide film of aluminum or aluminum alloy containing a trace amount of a rare gas component.
[0024]
By including the rare gas, the film stress is suppressed, and the adhesion and reliability are improved. As the rare gas, krypton (Kr) gas and xenon (Xe) are particularly preferable.
[0025]
Furthermore, the pump member of the present invention is made of an aluminum alloy containing at least one of magnesium, strontium, or barium in aluminum, and has an oxide film on the surface of the vacuum pump member. And at least one of the oxides of magnesium, strontium, and barium. Such a member for a plasma processing apparatus is further improved in corrosion resistance.
[0026]
The aluminum alloy may contain at least zirconium, or may contain at least hafnium. In the case of containing these, the mechanical strength is improved.
[0027]
Furthermore, the aluminum alloy preferably has a Fe, Mn, Cr, and Zn content of 0.01% by weight or less. This is because the corrosion resistance deteriorates when these metals are included.
[0028]
In the above description, the case where aluminum or an aluminum alloy is used as the base material of the vacuum pump member has been described. However, the present invention is not limited to this, and the surface of the base material formed of iron containing aluminum is subjected to plasma oxidation. An aluminum oxide film formed by treatment or oxygen radical oxidation treatment may be formed on the surface. In this case, a technique of forming an aluminum oxide film on the surface by selectively oxidizing aluminum contained in the base material by plasma treatment may be used. Examples of such a base material containing aluminum include stainless steel.
[0029]
As a method for forming an aluminum oxide film on the surface of a necessary portion of the pump member by plasma treatment or the like, a plasma treatment method described in Japanese Patent Application No. 2003-028476 can be applied.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described. Referring to FIG. 1, a cluster type vacuum processing system is shown as a vacuum processing system to which a vacuum pump according to the present invention can be applied. The vacuum processing system includes a plurality of reaction chambers (vacuum containers) 10, 11, 12. Two load lock chambers 13 and 14 and a transfer chamber 15 are provided.
[0031]
Further, in order to reduce the pressure in the reaction chambers (vacuum containers) 10, 11 and 12 or make them vacuum, each reaction chamber (vacuum container) 10, 11 and 12 is provided with one or more high vacuums. Pumps 1, 2, 3, booster pumps 4 a, 5 a, 6 a and back pumps (dry pumps) 4 b, 5 b, 6 b disposed after the high vacuum pump are provided. In the illustrated example, booster pumps 7a, 8a, 9a, and back pumps 7b, 8b, 9b are also connected to the load lock chambers 13, 14, and the transfer chamber 15, respectively. Valves 22, 23 and 24 are provided between the high vacuum pumps 1, 2 and 3 and the booster pumps 4a, 5a and 6a.
[0032]
There are turbo molecular pumps (screw groove pumps), cryopumps, mechanical booster pumps, back pumps (dry pumps), and scroll pumps. Hereinafter, the back pump (FIG. 2) will be described as an example.
[0033]
Here, the operation of the vacuum processing system shown in FIG. 1 will be described first. An object to be processed such as a wafer is loaded into the load lock chamber 13, and the object to be processed loaded into the load lock chamber 13 reacts via a transfer chamber 15 equipped with a robot (transport device) for transferring the object to be processed. It is transferred to the chambers 10, 11, 12. Further, when processed in the reaction chambers 10, 11, and 12, the object to be processed is transferred from the reaction chambers 10, 11, and 12 to the load lock chamber 14 through the transfer chamber 15.
[0034]
Furthermore, although not shown, the reaction chambers (vacuum containers) 10, 11, and 12 are provided with heating means such as a gas introduction port and a heater, and a film is formed while introducing a predetermined gas under heating. Predetermined processing is performed. Among these reaction chambers 10, 11, and 12, at least one reaction chamber is configured to perform plasma oxidation treatment and oxidation treatment with oxygen radicals. When such an oxidation treatment is performed, gas is decomposed in the reaction chamber to generate a corrosive gas, and the corrosive gas is sequentially exhausted by a plurality of stages of vacuum pumps illustrated.
[0035]
In FIG. 1, A1 indicates the piping between the high vacuum pumps 1, 2, 3 and the booster pumps 4a, 5a, 6a, and A2 indicates the reaction chambers (vacuum containers) 10, 11, 12 The piping between the vacuum pumps 1, 2, and 3 is shown. Moreover, R in the figure indicates a clean room.
[0036]
The illustrated vacuum processing system is first placed in a standby state. In this standby state, the transfer chamber 15 and the reaction chambers (vacuum containers) 10, 11, and 12 are maintained in a reduced pressure or vacuum state.
[0037]
In this state, a cassette containing a plurality of workpieces such as wafers is carried into the load lock chamber 13 from the atmosphere outside the vacuum processing system, and the load lock chamber 13 is evacuated.
[0038]
Next, a gate valve (not shown) between the load lock chamber 13 and the transfer chamber 15 is opened, and the workpiece transfer robot picks up the workpiece in the cassette by the transfer arm and moves to the transfer chamber 15. Let
[0039]
Thereafter, the gate between the reaction chamber (vacuum container) 10 and the transfer chamber 15 is opened, and the object to be processed is placed on the stage in the reaction chamber (vacuum container) 10 by the transfer arm. After a predetermined process such as a film forming process, the processed object is transferred to the other reaction chambers 11 and 12 or the load lock chamber 14 by the transfer arm. After the processing, it is finally transported from the load lock chamber 14 to the outside.
[0040]
Among the above reaction chambers 10, 11, and 12, at least from a chamber in which an oxide layer is formed on a workpiece by plasma oxidation or oxygen radicals, a highly reactive gas is supplied to a high vacuum pump and a booster pump. To the back pump. The present invention may be applied only to a vacuum pump that exhausts reactive gas, but here, high vacuum pumps 1, 2, 3, and booster pump 4a provided in all reaction chambers 1, 2, 3 are used. ˜9a and back pumps (dry pumps) 4b-9b are all constituted by the vacuum pump of the present invention.
[0041]
With reference to FIGS. 2 (a) and 2 (b), the vacuum pump of the present invention will be described taking the back pumps 4b to 9b as examples. The illustrated vacuum pump includes a screw pump main body A. The main body A has a plurality of spiral land portions and groove portions, and a pair of screw rotors 25 that rotate about two parallel axes while meshing with each other. , 26.
[0042]
The screw rotors 25 and 26 are housed in a casing 27 and are rotatably supported by bearings 35 at one end of a shaft 28 that supports the screw rotors 25 and 26. A timing gear 30 is attached to one end of the shaft 28, and a motor (not shown) is connected to the other end. When the shaft 28 is rotated by the motor, the pair of screw rotors 25 and 26 are rotated in synchronization via the timing gear 30.
[0043]
A suction port 31 is formed on one end side of the casing 27 that houses the screw rotors 25 and 26, and a discharge port 32 (FIG. 2B) is formed on the other end side of the casing 27. Yes. In this example, the suction port 31 is connected to the chamber side, and the discharge port 32 is connected to the atmosphere side. By rotating the screw rotors 25 and 26 synchronously by the motor, the gas from the chamber side is sucked from the suction port 31 and discharged from the discharge port 32. As a result, the gas in the chamber is exhausted.
[0044]
On the discharge port 32 side of the casing 27 shown in the figure, a jacket 33 is formed in which a hollow portion is formed so that cooling water can be circulated. In particular, the heat generation of gas based on the compression action on the discharge port 32 side is generated. It is configured to be cooled.
[0045]
A cover 34 is attached to one end of a casing 27 that houses the rotors 25 and 26, and one of the shafts 28 that support one screw rotor 26 projects from the cover 34, which will be described later. The motor is directly connected to the rotating shaft of the motor. Further, a seal member 29 is provided between the bearing 35 and the screw rotors 25 and 26.
[0046]
The members of the back pump (dry pump) shown in FIG. 2 are all made of aluminum or aluminum alloy as a base material, and among these members, the rotors 25 and 26, the casing 27, the seal member 29, and the suction member The port 31, the discharge port 32, and the like (and the shaft 28 in some cases) are exposed to the corrosive gas and the chemical solution during the discharge of the corrosive gas and the chemical solution. In this case, examples of the highly reactive gas or chemical include Cl-based gas, F-based gas, HCl, H ₂ SO ₄ , and HF.
[0047]
By applying the treatment according to the present invention to all the members constituting the back pump, the entire back pump can be given corrosion resistance. Here, the member exposed to the corrosive gas, that is, the rotor 25 is used. 26, the casing 27, the seal member 29, the suction port 31, and the discharge port 32, at least the surfaces exposed to the gas are subjected to plasma oxidation treatment or oxygen radical oxidation treatment according to the present invention. As a result, as shown in FIG. As shown in bold lines in b), an aluminum oxide film is formed on the surface of each member. As described above, the aluminum oxide film formed by the plasma oxidation process or the oxidation process using oxygen radicals has a feature that it has no voids, is extremely dense, and has a flat surface. For this reason, high corrosion resistance can be maintained even for highly reactive gases.
[0048]
With reference to FIG. 3, a method for forming the above-described aluminum oxide film on the vacuum pump member using the plasma processing apparatus 1 will be described. The illustrated plasma processing apparatus 1 performs processing of the vacuum pump member 40 shown in a rectangular shape. The plasma processing apparatus 1 includes a bottomed cylindrical processing container 2 made of, for example, an aluminum alloy and having an open top, and the processing container 2 is grounded. A susceptor 3 on which the vacuum pump member 40 is placed is provided at the bottom of the processing container 2. The susceptor 3 is made of, for example, an aluminum alloy, and the heater 5 of the susceptor 3 generates heat by power supplied from the AC power supply 4 provided outside the processing container 2, and the vacuum pump member 40 on the susceptor 3 is heated to 300 ° C. .
[0049]
An exhaust device 41 such as a turbo molecular pump is connected to the bottom of the processing container 2 via an exhaust pipe 42, and the inside of the processing container 2 is exhausted by the exhaust device 41. Further, a supply pipe 44 for supplying a processing gas from a processing gas supply source 43 is provided on the side wall of the processing container 2. In the present embodiment, the processing gas supply source 43 is connected with respective supply sources 45 and 46 of oxygen gas (O 2) and inert gas argon (Ar) gas.
[0050]
A dielectric window 22 made of, for example, quartz glass is provided in the upper opening of the processing container 2 via a sealing material 21 such as an O-ring for ensuring airtightness. A processing space S is formed in the processing container 2 by the dielectric window 22.
[0051]
An antenna member 51 is provided above the dielectric window 22. In this example, the antenna member 51 covers, for example, the radial slot antenna 52 located on the lowermost surface, the slow wave plate 53 located on the upper part thereof, and the slow wave plate 53 to protect the slow wave plate 53 and cool it. The antenna cover 54 is configured.
[0052]
The radial slot antenna 52 is made of a conductive material, for example, a thin disk of copper, and a pair of slits having an acute angle close to a right angle are aligned concentrically and formed in the disk. .
[0053]
At the center of the slow wave plate 53, a bump 55 constituting a part of a conical shape made of a conductive material such as metal is disposed. The bump 55 is electrically connected to the inner conductor 56a of the coaxial waveguide 56 constituted by the inner conductor 56a and the outer tube 56b. The coaxial waveguide 56 is configured to propagate, for example, 2.45 GHz microwave generated by the microwave supply device 57 to the antenna member 51 through the coaxial waveguide 56 via the load matching device 58.
[0054]
Next, a plasma processing method performed in the illustrated vacuum processing system 1 will be described. First, a vacuum pump member 40 formed of aluminum or an aluminum alloy is placed on the susceptor 3. In this state, oxygen gas containing krypton is supplied from the supply source 45, and plasma is generated in the processing container 2. The In this case, the vacuum pump member 40 is maintained at a temperature of 450 ° C. or lower (preferably 150 ° C. to 250 ° C.). Note that plasma could be generated in the processing vessel 2 even when the vacuum pump member 40 was kept at room temperature (for example, 23 ° C.).
[0055]
When the plasma was generated, oxygen radicals were generated in the processing container 2, and the surface of the vacuum pump member 40 was oxidized by the oxygen radicals to form an oxide film.
[0056]
As described above, it was confirmed that the oxide film generated by the oxidation treatment with oxygen radicals was an Al ₂ O ₃ film having no voids, extremely dense and having a flat surface. This is because the surface of aluminum or aluminum alloy was modified by oxygen radicals.
[0057]
The reaction formula at this time is as follows.
[0058]
2Al + 3O ^* → Al ₂ O ₃
[0059]
Furthermore, when the vacuum pump member 40 is formed of an aluminum alloy containing magnesium (Mg), an oxide film (Al ₂ O ₃ ) containing a large amount of MgO can be formed on the aluminum alloy surface by oxygen radicals. Thus, the oxide film containing MgO can improve corrosion resistance and strength. In this case, the magnesium content is preferably 0.5% by weight to the maximum amount of solid solution (about 6.0% by weight). In addition, when oxygen radicals containing krypton are converted into plasma to generate oxygen radicals, the magnesium content is an oxidation containing MgO even at a very low content of 0.5% to 1.0% by weight. A physical coating could be obtained.
[0060]
As the aluminum alloy, aluminum alloys containing strontium, barium, zirconium, and hafnium can be used in addition to the above-described magnesium. The corrosion resistance and strength of the vacuum pump member 40 could be improved by forming an oxide film containing a large amount of SrO and BaO on the aluminum alloy surface.
[0061]
Further, when an aluminum alloy containing about 0.1 to 0.15% by weight of zirconium is used, the vacuum pump member 40 having high corrosion resistance and high mechanical strength can be configured by suppressing alloy grain growth. Further, it was confirmed that even when an aluminum alloy containing 0.1 to 0.15% by weight of hafnium was used, a vacuum pump member having high corrosion resistance and high mechanical strength was obtained by suppressing alloy grain growth.
[0062]
On the other hand, the aluminum alloy often contains Fe, Mn, Cr, and Zn, and these usually reduce the corrosion resistance of the aluminum alloy, so that their content is 0.01% by weight or less. It is desirable to be. Note that Fe, Mn, Cr, and Zn in the aluminum alloy can be removed by hydrogen reduction of the vacuum pump member 40 at a temperature of 450 ° C. or less before the oxidation treatment.
[0063]
In the case of generating oxygen radicals by plasma, the case of generating plasma by mixing krypton (Kr) into an oxygen-containing gas has been described. This is because krypton excited to a high energy state by mixing krypton gas. This is because it can collide with oxygen molecules and easily generate two oxygen radicals.
[0064]
In generating oxygen radicals, oxygen plasma may be generated using a gas in which argon (Ar) gas is mixed into an oxygen-containing gas. When argon gas is used, since argon gas is easy to handle and inexpensive, the vacuum pump member 40 can actually be processed easily and inexpensively.
[0065]
As described above, when plasma is generated using a rare gas such as krypton or argon, and plasma oxidation treatment, for example, oxidation treatment with oxygen radicals is performed, a small amount of rare oxide is contained in the generated oxide film. A gas component will be contained. This rare gas component is useful for suppressing the film stress of the oxide film and improving the adhesion and reliability.
[0066]
As the plasma source for generating oxygen plasma, the above-described plasma processing apparatus 1 uses microwave plasma having a frequency of 2.45 GHz. Since the microwave plasma is a gentle plasma with a high density and a relatively low Vdc, the surface of the vacuum pump member 40 is radically oxidized without damaging the surface of the aluminum or aluminum alloy, thereby forming an oxide film. Can be formed.
[0067]
Further, in the above-described example, only the case where the vacuum pump member 40 is formed of aluminum or an aluminum alloy has been described. However, the present invention is not limited to this, and is configured by a stainless steel containing aluminum. Similar results were obtained when an aluminum oxide film was formed on the surface of the vacuum pump member.
[0068]
Further, the pump to which the present invention is applied is not limited to the pump shown in FIG. 2, and is generally applied to a pump that is exposed to a highly corrosive gas or chemical solution. There is an effect by applying a film containing an oxide.
[0069]
【The invention's effect】
According to the present invention, a dense and flat coating film is formed and the corrosion resistance is improved as compared with the case of conventional anodizing treatment.
[Brief description of the drawings]
FIG. 1 is an exhaust system diagram for carrying out an embodiment of the present invention.
FIG. 2A is a cross-sectional view of a back pump of an exhaust system for carrying out an embodiment of the present invention.
(B) is another cross-sectional view of the back pump shown in FIG.
FIG. 3 is a schematic cross-sectional view showing a plasma processing apparatus used for the processing of the present invention.
[Explanation of symbols]
1, 2, 3 High vacuum pump 10, 11, 12 Reaction chamber 13, 14 Load lock chamber 15 Transfer chamber 4a-9a Booster pump 4b-9b Back pump (dry pump)
25, 26 Screw rotor 27 Casing Liu rotor 28 Shaft 35 Bearing 29 Seal member 31 Suction port 32 Discharge port 33 Jacket

Claims (11)

An exhaust pump having a gas suction port and a gas discharge port to be exhausted, wherein the member exposed to the gas is made of an aluminum alloy,
In the evacuated processing vessel, the member is kept at 450 ° C. or lower, oxygen gas containing a rare gas component is supplied, and an oxide film oxidized by oxygen radicals generated by microwave plasma processing is provided as a surface layer. And the surface layer includes an oxide film of an aluminum alloy containing a rare gas component,
The member is subjected to hydrogen reduction at a temperature of 450 ° C. or lower before the oxidation treatment, so that the contents of Fe, Mn, Cr, and Zn are all 0.01% by weight or less. pump. The exhaust pump according to claim 1, wherein the rare gas component is krypton or xenon. The exhaust pump according to claim 1 or 2, wherein the aluminum alloy contains at least one selected from the group consisting of magnesium, strontium, barium, zirconium, and hafnium. The exhaust pump according to claim 3, wherein the oxide film further includes at least one oxide of magnesium, strontium, barium, zirconium, and hafnium oxides. A member used in a vacuum processing system and exposed to a medium to be evacuated from the vacuum system is made of an aluminum alloy, and the member is kept at 450 ° C. or lower in the evacuated processing container and contains an oxygen gas. supplying, to a portion to be exposed to the medium, the oxide film is oxidized by oxygen radicals generated by microwave plasma treatment was useful as a surface layer, the surface layer of aluminum alloy containing a rare gas component Including an oxide coating;
The member is subjected to hydrogen reduction at a temperature of 450 ° C. or less before the oxidation treatment, so that the contents of Fe, Mn, Cr, and Zn are all 0.01% by weight or less. pump. The rare gas component is a vacuum pump according to claim 5, characterized in that krypton or xenon. The vacuum pump according to claim 5 or 6, wherein the aluminum alloy contains at least one selected from the group consisting of magnesium, strontium, barium, zirconium, and hafnium. The vacuum pump according to claim 7, wherein the surface layer includes at least one oxide of magnesium, strontium, barium, zirconium, and hafnium. The vacuum processing system, the vacuum pump according to any one of claims 5 to 8, characterized in that a plasma processing apparatus for performing plasma treatment. The medium, Cl-based gas or chemical solution, F-based gas or chemical solution, HCl gas or chemical _solution, H 2 SO ₄ gas or chemical or any one of claims 5 to 9, characterized in that a HF gas or chemical solution, The vacuum pump according to item . In a method of manufacturing a vacuum pump member that is exposed to a medium exhausted from a vacuum system,
The vacuum pump member is formed of an aluminum alloy ;
By reducing the vacuum pump member with hydrogen at a temperature of 450 ° C. or less, the Fe, Mn, Cr, and Zn contents are all 0.01% by weight or less,
An oxide of aluminum is obtained by maintaining the vacuum pump member at 450 ° C. or less in the exhausted processing container and supplying oxygen gas containing a rare gas component and oxidizing it with oxygen radicals generated by microwave plasma processing. A method of manufacturing a vacuum pump member, wherein the coating film is formed as a surface layer .

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