JP2003065285A - Pump member, turbo molecular pump and surface finished layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pump member provided with both corrosion resistance and high radiation rate and a turbo molecular pump with this pump member applied as a rotor and to provide a surface finished layer which can generally give the above performances to optional members. SOLUTION: On the surface of the rotor which is a component of the turbo molecular pump, the surface finished layer S is formed. This surface finished layer S is made of a first layer which is a metal plated layer S1 made of Ni-P alloy formed by electroless plating and a second layer which is a resin layer S2 formed by electropainting a fluorocarbon resin. An intermediate layer SM made of amorphous organic metal coating is provided between the metal plated layer S1 and the resin layer S2. By this constitution, corrosion resistance is improved by the metal plated layer S1 and the resin layer S2, and heat radiation by the resin layer S2, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum pump used in a semiconductor process or the like, and a pump member constituting the vacuum pump. More particularly, the present invention relates to a turbo molecular pump when the pump member corresponds to a rotor, and generally to a surface treatment layer that can be formed on the surface of any member.

[0002]

2. Description of the Related Art A semiconductor process is realized by various steps including optical treatment and chemical treatment. As a typical example of the optical processing, there is an exposure processing for printing a circuit pattern on the wafer surface, and in the chemical processing, for example,
Surface treatment such as forming a thin film on the wafer surface, etching treatment, cleaning treatment, etc. may be mentioned. Further, in order to realize these processes, an exposure apparatus is used in the optical process, various chemicals in the chemical process, and various devices for safely handling the chemicals. In these various processes or various devices and equipment, as the demand for higher integration of semiconductors is increasing, each of them is required to have a technically high level, and further development is required. In order to achieve this, research and development will be carried out at various places concerned.

[0003] Among them, a specific technique is an etching technique for forming a groove on the surface of a substrate, paying attention to a chemical treatment process. This etching is a technique of supplying a source gas onto a substrate such as a wafer and generating plasma to cause a chemical reaction on the substrate to form a desired groove in the substrate. This technique is indispensable for realizing high integration of semiconductors such as thinning of gates and reduction of capacitance between wirings.

By the way, in order to realize the above etching, a device for realizing a stable supply of gas and a region around the substrate surface are cleared so that a chemical reaction on the substrate surface can effectively proceed. Equipment for maintaining the environment is needed. It should be noted that many gases used in etching are generally extremely toxic, and their handling requires careful attention. Therefore, it is indispensable to consider that point for gas supply equipment and equipment for recovering it. Further, as a method of "keeping the area around the substrate surface clear", specifically, a means of exposing a vacuum atmosphere is generally used, and therefore, a vacuum exhaust system is prepared to realize it. Becomes

As the above-mentioned vacuum exhaust system, generally, a system constituted by a plurality of pumps such as a rotary pump, a diffusion pump, a turbo molecular pump, etc. is used so as to enable multistage exhaust from atmospheric pressure. Among them, the vacuum exhaust system including the turbo molecular pump realizes an ultra-high vacuum whose vacuum degree reaches about 10-10 Torr. As is well known, the turbo molecular pump is
The structure is such that gas molecules are exhausted while being compressed by a rotor that rotates at approximately 90,000 rpm. Here, as the rotor, since it is a member that rotates at a very high speed as described above, it is general that an aluminum alloy that is lightweight and has high stress strength is selected as the material.

[0006]

By the way, among the above-mentioned toxic gases in etching, there are corrosive gases. For example, dry chlorine gas Cl2 is known to corrode aluminum. Moreover,
Performance is improved by adding oxygen to the above-mentioned etching gas, but it is also known that this oxygen becomes active oxygen due to plasma and deteriorates a specific organic substance. On the other hand, the turbo molecular pump prepared as an evacuation system naturally also sucks the gas used for etching. The rotor that constitutes the turbo molecular pump is made of an aluminum alloy as described above. As is clear from these facts, it is necessary to pay great attention to using a turbo molecular pump in a semiconductor process that generally includes etching and the like. That is, it can be said that there is a technical problem that avoids corrosion of the rotor member due to toxic gas and always enables stable operation of the exhaust system.

Further, the technical problems relating to the turbo molecular pump are not limited to the above circumstances. That is,
The rotor needs to be configured so that heat can be easily dissipated, that is, the emissivity is high. this is,
This is because the rotor rotates at a very high speed as described above and a large amount of heat is generated. Further, in particular, when a situation occurs in which the rotor sucks more gas than the assumed gas suction amount, the amount of heat generated increases dramatically. If the generated heat is left as it is, creep will occur in the rotor rotor blades, and this will have a great influence on the operation of the turbo molecular pump. On the other hand, however, since the turbo molecular pump is supposed to operate in an ultra-high vacuum degree, heat dissipation due to a convection phenomenon that is normally expected is not promoted in an atmosphere in which the rotor rotates. Therefore, it can be said that this problem is present as a more serious technical problem.

[0008] The two problems just mentioned are generally in conflict with each other when trying to solve them.
In other words, as a measure for solving the former problem, conventionally, a means such as nickel-plating the rotor surface to provide corrosion resistance has been taken, but in this case the emissivity is not sufficient and occurs in the rotor. The heat could not be dissipated quickly. Conversely, with the latter issue in mind,
Considering that a coating film having a high emissivity is applied to the rotor surface, in this case, the corrosion resistance is insufficient and the gas is immediately corroded. Furthermore, as a method for solving the above two problems, Japanese Patent Application No. 10-218256 proposes a two-layer coating in which a nickel plating film is subjected to an epoxy resin coating treatment. Although this technique is effective against halogen gas such as chlorine and can protect the aluminum base material, it is insufficient in an oxygen plasma environment, and two problems cannot be solved at the same time.

In short, until now, effective means for solving the above two problems at once have not been developed. Therefore, practical measures are sufficient for the operation of the turbo molecular pump. It only calls attention to the user, which imposes an extra burden on the user. The above description is not limited to the turbo molecular pump.

The present invention has been made in view of the above circumstances. An object of the present invention is to provide a pump member having both corrosion resistance and high emissivity, and a turbo molecular pump using the pump member as a rotor. To provide. Another object of the present invention is to provide a surface-treated layer that can impart the above-mentioned performance to any member.

[0011]

The present invention takes the following means in order to solve the above problems. That is, the pump member according to claim 1 is a pump member having a metal plating layer formed on a base material and a resin layer formed on the metal plating layer, wherein the resin layer is a fluorine-based material. It is characterized by using resin as a material.

It can be said that this pump member is capable of exhibiting a sufficient corrosion resistance by the metal plating layer and also having a high emissivity by the resin layer. In addition, the resin layer made of a fluororesin has effective corrosion resistance against corrosive gas and active oxygen, so that more effective heat dissipation can be realized.

A pump member according to a second aspect is characterized in that an intermediate layer is provided between the metal plating layer and the resin layer.

According to this, it can be expected that the adhesion strength between the metal plating layer and the resin layer is sufficiently ensured by the intermediate layer. Therefore, it becomes possible to obtain a highly stable surface treatment layer which is not easily peeled off.

A pump member according to a third aspect of the present invention is characterized in that the metal plating layer is formed by electroless plating.

According to this, the base material and the metal plating layer are firmly attached. Further, as is a concern in electroplating, there is no need to worry about a situation in which plating progresses in a portion where a current is concentrated, such as a protrusion, so that plating is unevenly formed on the entire surface of the member. That is, it becomes possible to form a surface treatment layer having a uniform thickness over the entire surface of the pump member.

A pump member according to a fourth aspect is characterized in that the resin layer is formed by electrodeposition coating.

This ensures that the metal plating layer or the intermediate layer and the resin layer are firmly attached.
Further, by using the cationic electrodeposition coating, it is possible to form a uniform coating film on a pump member having a complicated shape, and at the same time, a high-quality coating film without sagging or melting of the coating film. Can be formed.

A pump member according to a fifth aspect of the present invention is characterized in that the metal plating layer is made of nickel.

According to this, it is possible to expect a more effective action in terms of corrosion resistance and emissivity. That is, it becomes possible to exert more effective resistance to the corrosive gas and to realize more effective heat dissipation.

A pump member according to a sixth aspect is a rotor having an aluminum alloy as a base material.

According to this, since the pump member is a rotor, it is generally envisaged that it will be used in the construction of a turbomolecular pump. Further, in a rotor that rotates at high speed in an atmosphere of ultra-high vacuum and corrosive gas, the action obtained by including the metal plating layer and the resin layer, that is, corrosion resistance,
It is possible to make the most of the effect of high emissivity.

A turbo molecular pump according to a seventh aspect of the present invention comprises a nickel layer formed by electroless plating on a base material made of an aluminum alloy, and a fluorine resin layer formed by electrodeposition coating on the nickel layer. It is characterized by including a rotor having.

It is clear that this turbo-molecular pump can obtain the various actions described above.

In the surface treatment layer according to claim 8, the first layer is a nickel alloy layer formed by electroless plating, and the second layer is a resin layer formed by electrodeposition coating of a fluororesin. It is characterized by being

Since the surface treatment layer has been described so far, it is composed of a uniform plating layer and a coating film having excellent effects such as corrosion resistance, high emissivity, and high adhesion strength between layers. It can be said to be a thing. Further, by forming this surface treatment layer on the surface of an arbitrary member that is generally exposed to the atmosphere in which the above-mentioned respective performances are required, it becomes possible to utilize its action to the maximum extent.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration of the turbo molecular pump P. In the present embodiment, the description will be given assuming that the rotor 4 shown in FIG. 1 corresponds to the pump member in the claims. In the following, first, the structure of the turbo molecular pump P will be described, and then the surface treatment layer S (FIG. 2) formed on the surface of the rotor 4 will be described. Finally, focusing on the surface treatment layer S,
The method of manufacturing the rotor 4 will be described, and the properties of the surface treatment layer S will be described.

The turbo molecular pump P has a structure in which various devices are provided inside a casing 1 composed of an upper half portion 1a and a lower half portion 1b. In the casing 1, an intake port 1c is formed in the upper half 1a and an exhaust port 1d is formed in the lower half 1b.

A rotor 4 is disposed in a rotor chamber 2 inside the casing 1. The rotor 4 includes a rotor shaft 4 a that is vertically installed and the rotor shaft 4 a.
It is configured to include the moving blades 5 that are radially arranged around a. In addition, stationary vanes 3 are fixed to the upper half 1a of the casing. Since the rotor 4 is a member that rotates at a high speed as described later, it is generally preferable to select an aluminum alloy or the like that is lightweight and has high stress strength as its material.

A thrust magnetic disk 6 is provided at the lower end of the rotor shaft 4a. Thrust magnetic bearings 8 are provided on the upper and lower surfaces of the thrust magnetic disk 6 so as to face the thrust magnetic disks 6. Further, the radial magnetic bearings 7a and 7a are provided above and below the facing surfaces of the rotor shaft 4a and the lower casing half 1b, respectively.
b is provided. Further, a ball bearing 9 provided as an upper protective bearing for radial on the upper end portion of the rotor shaft 4a, and a ball bearing 10 provided as a lower protective bearing for radial and thrust on the lower end neck portion thereof. And the lower half 1b of the casing
Is provided with a rotor driving motor 11.

The turbo molecular pump P in this embodiment
As is clear from the above-mentioned configuration, has an active magnetic bearing as a bearing, and the rotation of the rotor 4 is realized by these and the driving force generated by the rotor driving motor 11. At this time, the rotation speed of the rotor 4 is about
At 90,000 rpm (1500 rpm), the temperature reaches about 130 ℃ even during normal operation. The present invention is not limited to this with respect to the configuration of the turbo molecular pump P, and it goes without saying that the present invention is also applicable to a turbo molecular pump using a ball bearing type and other bearings.

The turbo-molecular pump P having the above-mentioned structure is used, for example, by being attached to an etching apparatus used in a semiconductor process as a part of an exhaust system together with a rotary pump, a diffusion pump and the like. That is, it is used for the purpose of exhausting the inside of the chamber attached to the etching apparatus at the same time. In the etching apparatus, a gas for chemically reacting with the surface of the substrate is supplied into the chamber, so that the turbo molecular pump P inevitably sucks this gas as well. By the way, as described above, many of these gases are generally toxic, and in the case of trimethylgallium Ga (CH3) 3, which has a corrosive effect on aluminum, and dry chlorine gas Cl2, a turbo molecular pump is used. It can be said that the gas is a particularly problematic gas for the rotor 4 made of P, that is, the aluminum alloy. Further, oxygen is added to these gases to improve the etching performance.

Next, the structure of the rotor 4 will be described in detail. FIG. 2 is a partially enlarged view of a cross-sectional view of the rotor blade 5 that constitutes the rotor 4. The rotor 4, that is, the moving blade 5, is made of an aluminum alloy as described above. More specifically, JIS2014, JIS2618, etc.,
It is preferable to use an aluminum alloy (Al-Cu based alloy) in the 2000 series according to the JIS classification number.

A surface treatment layer S is formed on the entire surface of the rotor 4. The surface treatment layer S has a large two-layer structure as shown in FIG. 2. The first layer is the metal plating layer S1 and the second layer is the resin layer S2. In the present embodiment, the former metal plating layer S1 is made of nickel and is formed by electroless plating. More specifically, it is formed as a Ni-P alloy or a Ni-B alloy. Further, the resin layer S2 is made of a fluororesin by electrodeposition coating.

The thicknesses of the metal plating layer and the resin layer are preferably about 50 μm and about 20 μm, respectively. As for the thickness of the metal plating layer, it is 50
If it exceeds .mu.m, it may impose a load on the rotation of the rotor 4, and conversely, if it is too thin, it may be impossible to obtain sufficient corrosion resistance. This is why a thickness of 50 μm is most preferred. Also,
The same applies to the thickness of the resin layer. The thickness of the surface treatment layer S as a whole (70 μm in this example) has to be considered in consideration of the rotation performance of the rotor 4 as described above, and thus it is more preferable to make it as thin as possible. It can be said that it is in a state.

An intermediate layer SM is provided between the metal plating layer and the resin layer described above. This middle layer SM
Is an amorphous organic metal film formed by subjecting the surface of the metal plating layer S1 to chemical conversion treatment using a Cr-free surface treatment chemical for a coating base. Due to the presence of the intermediate layer SM, the adhesion between the metal plating layer S1 and the resin layer S2 is improved, and the action of strengthening the corrosion resistance is obtained. However, as shown in FIG. 3, the intermediate layer S may be omitted depending on the size of the turbo molecular pump.

A rotor 4 including such a surface treatment layer S
Will be manufactured by the following procedure. First, an aluminum alloy processed into a cylindrical shape is prepared, and is ground by a lathe or the like so that the surface of the aluminum alloy substantially matches the outer shape of the rotor 4. Then, after further roughening the shapes of the plurality of moving blades 5 from this surface,
A precise shape is finally given to each of these moving blades 5 by a method such as electric discharge machining or machining center machining. This completes the shaping of the rotor 4, and then proceeds to the step of forming the surface treatment layer S. Therefore, the rotor 4 at this point corresponds to the "base material" in the claims.

First, the metal plating layer S1 described above is formed on the rotor 4. However, before that, rotor 4
Pretreatment such as cleaning and etching of the surface is performed.
The metal plating layer S1 is formed by electroless plating, as will be described later, but this pretreatment is not different from what is usually performed as a pretreatment for the electroless plating. If you simply follow the steps, alkaline degreasing,
The pretreatment in the present embodiment is constituted by the treatments of etching, smut removal, first zincate treatment, zincate peeling, second zincate treatment, and neutralization treatment.
By the way, it goes without saying that a water washing treatment is inserted between the above treatments.

The metal plating layer S1 is formed by an electroless plating method after the above-mentioned pretreatment is completed and washing with water is performed. Electroless plating is a plating method that chemically progresses under the conditions in which cathodic deposition of metal and anodic oxidation of a reducing agent occur simultaneously. That is, unlike the case where an external DC power source is provided as in the case of electroplating, the metal ion automatically advances the metal deposition when the metal ion receives the electron emitted by the reducing agent. In this embodiment, a Ni-P alloy is selected as the metal, and this is deposited on the surface of the rotor 4.

The electroless Ni (Ni-P) plating step is specifically performed as follows. First, an aqueous solution of sodium phosphinate as a reducing agent is poured into a suitable container. In the present embodiment, top nicolones BL-M and BL-1 (manufactured by Okuno Seiyaku Co., Ltd.), which are easily commercially available, were used. The concentrations were 100 ml and 60 ml, respectively, per liter of the aqueous solution. The electroless Ni plating is completed by keeping the aqueous solution at 90 ° C. and immersing the rotor 4 for 4 hours.

In this case, unlike Ni plating by electroplating, it becomes possible to form a uniform Ni-P layer on the surface of the rotor 4. This is because the rotor 4 has an extremely complicated shape as shown in FIG. 1, and if electroplating is applied to this, the protrusions (for example, the tips of the moving blades 5) will be formed. This is because the electric current is concentrated and the plating of that portion progresses more than other portions, so that there is a high possibility that a non-uniform plating layer is formed in the entire rotor 4. Therefore, it can be said that the use of the electroless plating method is very effective for a member having a complicated shape such as the rotor 4.

After the formation of the metal plating layer S1 is completed, the surface of the metal plating layer S1 is subjected to chemical conversion treatment. This corresponds to a pretreatment for the next electrodeposition coating of the resin layer S2. By performing this chemical conversion treatment, the intermediate layer SM made of the amorphous organic metal film is formed, and the adhesion between the metal plating layer S1 and the resin layer S2 is improved. The method of forming the intermediate layer SM may specifically be based on a method of performing a chemical conversion treatment that is usually performed when performing electrodeposition coating on stainless steel. For example, the intermediate layer SM is manufactured by the following steps.
Is formed. First, the surface of the metal plating layer S1 is washed and dried. Then, the entire rotor 4 is immersed for 5 to 30 seconds in an aqueous solution of Palcoat 3841 (commercially available, manufactured by Nippon Parka) whose temperature is from room temperature to about 40 ° C. Finally, it is completed by pulling it up and drying it without washing with water.

After the formation of the intermediate layer SM is completed, the resin layer S2 is formed next. The resin layer S2 is formed by electrodeposition coating. Electrodeposition coating is an aqueous solution in which a resin is neutralized with a neutralizing agent and ionized, and by applying a direct current voltage by immersing the article to be coated, electromigration, electrolysis, electroprecipitation on the article to be coated, This is a method of causing electroosmosis to form a resin coating film on the article to be coated.

In this embodiment, the resin layer S2 is specifically formed by the following steps. First, an aqueous solution containing a fluorine-based electrodeposition paint is poured into a suitable container. For example, Elecoat Niceron (trade name, manufactured by Shimizu)
To use. Further, a negative electrode made of stainless steel or the like is installed in the vicinity of the side wall inside the container. The rotor 4 which has been subjected to the above steps is immersed in such a container, and the negative electrode is electrically connected to the negative electrode via a DC power source. That is, in this case, the rotor 4 becomes a positive cathode. After that, between the negative electrode and the rotor 4, 15
A voltage of 0 V is applied and the state is maintained for 2 to 3 minutes. Then, the coating film forming mechanism described above forms a coating film of the fluororesin, that is, the resin layer S2 on the surface of the rotor 4.

In this case, as is generally said as an advantage of applying the electrodeposition coating, the uniform resin layer S2 is formed even for the rotor 4 having a complicated shape. In addition, the resin layer S is also of high quality with no sagging or burn-through of the coating film. In addition, the resin layer S2
The adhesion to the underlayer becomes extremely strong in combination with the presence of the intermediate layer SM.

Finally, in the rotor 4 which has undergone the above steps,
After performing a water washing treatment, a baking treatment is performed. Specifically, predrying may be performed in a firing furnace or the like at 110 ° C. for about 20 minutes, and baking may be performed at 180 ° C. for about 30 minutes. This is carried out in order to release the blocking agent existing immediately after the electrodeposition coating and at the same time realize the cross-linking of the coating film to ensure the adhesion of the resin layer S2.

With respect to the rotor 4 including the surface-treated layer S obtained through the above manufacturing process, the emissivity ε of the surface-treated layer S was measured and the corrosion resistance test result was shown in Table 1. Table 2 shows the temperature measurement results of the rotor 4 when the rotor 4 was actually operated in a vacuum atmosphere. In addition, the corrosion resistance test uses oxygen in chlorine gas.
After adding 10% and performing plasma treatment for 50 hours, the whole rotor 4 was immersed in an aqueous HCl solution, and the time when corrosion of the base material started was measured to perform the evaluation.

[0048]

[Table 1]

[0049]

[Table 2]

In Tables 1 and 2, two examples to be compared with the surface treatment layer S of the present embodiment are those in which only electroless Ni plating is applied to the base material,
It has a Ni plating and an epoxy resin coating formed on a base material. First, as can be seen from Table 1, in the surface treatment layer S of this embodiment, the emissivity ε is 0.2, while the emissivity ε is significantly improved to ε = 0.9. Based on this, when comparing the temperature measurement results in Table 2 and this embodiment, the temperature rises to 130 ° C. in the former case, while it is suppressed to 100 ° C. in the present embodiment. You can see that Also, returning to Table 1, in the emissivity ε
Is 0.9 and the same value as this embodiment, but 50 in the corrosion resistance test.
Corrosion of the base material started after a lapse of time, whereas the surface treatment layer S in the present embodiment did not start corrosion even after being immersed for 200 hours.

As described above, it can be seen that the surface-treated layer S in this embodiment has both high emissivity and excellent corrosion resistance. Therefore, considering the case where the rotor 4 on which the surface treatment layer S is formed is provided in the turbo molecular pump P described above and is further installed in an etching device or the like, the heat generated from the rotor 4 is generated in an ultrahigh vacuum. It is possible to effectively disperse even underneath, and it is possible to suppress the possibility of creep damage to the moving blades 5 and the like to an extremely small level, and to easily corrode even if the rotor 4 is exposed to corrosive gas. It never happens. In particular, the anticorrosion property is extremely high even in an active oxygen atmosphere in oxygen plasma. That is, the stable operation of the turbo molecular pump P can be always performed, and
It can support the implementation of extremely reliable semiconductor processes.

In the above embodiment, the rotor 4 in the turbo molecular pump P is described as a pump member, but the present invention is not limited to this. That is, the present invention is also applicable to pump members other than the rotor 4, which may generate heat in a vacuum atmosphere and may be exposed to corrosive gas. In addition, the pump member in this case is not limited to the turbo molecular pump P, and the pump members in the rotary pump, the diffusion pump and the like as exemplified above are also included in the concept.

In other words, the present invention is not limited to the pump member as long as it is a member that can be used in the above-mentioned environment, and in general, any member can be applied to the above-described embodiment on the surface thereof. It does not prevent that the surface treatment layer S as described above is formed and the effects thereof are enjoyed. That is, the present invention also includes this in the range.

Further, the metal plating layer S1 can be replaced with a metal that can be formed by electroless plating, such as Ni-P alloy, Cr, Co, or Au in some cases, in addition to the above Ni-P alloy. .

[0055]

As described above, the pump member according to the first aspect has the metal plating layer formed on the base material and the resin layer formed on the upper surface thereof, and therefore has sufficient corrosion resistance. It can be said that it has both properties of high emissivity. Therefore, ultra high vacuum etc.
In an environment where it is difficult to dissipate heat and an environment in which corrosive gas flows, the pump member can exhibit effective heat dissipation ability and corrosive gas resistance ability. Moreover, by forming a resin layer made of a fluororesin, the corrosion resistance, particularly the corrosion resistance against a halogen gas containing active oxygen and the heat dissipation capability can be more effectively utilized.

In the pump member according to the second aspect, since the intermediate layer is provided between the metal plating layer and the resin layer, the adhesion of both layers is sufficiently guaranteed by the intermediate layer.
Therefore, it is possible to obtain a highly stable surface treatment layer which is not easily peeled off.

In the pump member according to claim 3, since the metal plating layer is formed by electroless plating,
It is possible to surely adhere and form a uniform plated layer.

In the pump member according to the fourth aspect, since the resin layer is formed by electrodeposition coating, the pump member is of high quality with reliable adhesion, uniform coating film formation, and no sagging or melt-through. A coating film can be formed.

In the pump member according to the fifth aspect, since the metal plating layer is made of nickel, more effective action can be expected with respect to corrosion resistance and emissivity.

Since the pump member according to claim 6 is a rotor based on an aluminum alloy, it is generally envisaged that it will be used in the construction of a turbo molecular pump. Further, since the rotor in this case is a member that rotates at high speed in an atmosphere of ultra-high vacuum and corrosive gas, the effects obtained from the actions of corrosion resistance and high emissivity described above are most effectively utilized. be able to. Further, since the rotor is a member that rotates at a high speed, the function and effect of reliable attachment can be effectively utilized at the same time.

A turbo molecular pump according to a seventh aspect of the present invention comprises a nickel layer formed by electroless plating on a base material made of an aluminum alloy, and a fluorine resin layer formed by electrodeposition coating on the nickel layer. Is provided with a rotor. Therefore, this turbo-molecular pump can enjoy the various operational effects described above, and can perform stable operation.

In the surface-treated layer according to claim 8, the first layer is a nickel layer formed by electroless plating, and the second layer is a resin layer formed by electrodeposition coating of a fluororesin. . Therefore, this surface treatment layer has corrosion resistance,
It has excellent effects such as high emissivity, high adhesion strength between layers, and uniformity of layers. In addition, by generally forming the surface treatment layer on the surface of an arbitrary member used in the scene where the above-mentioned respective performances are required, it is possible to maximize the effects thereof.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration of a turbo molecular pump, which is partially cross-sectional view.

FIG. 2 is an enlarged cross-sectional view of a part of a rotor.

FIG. 3 is a cross-sectional view in which a part of the rotor is enlarged as in FIG. 2, and in particular, an intermediate layer is omitted.

[Explanation of symbols]

4 rotor P turbo molecular pump S surface treatment layer S1 metal plating layer S2 resin layer

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C25D 13/06 C25D 13/06 C F04D 19/04 F04D 19/04 C (72) Inventor Tomoaki Okamura Hiroshima Prefecture 4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima City Mitsubishi Heavy Industries, Ltd. Hiroshima Factory F-term (reference) 3H022 AA03 BA04 CA55 DA13 3H031 BA01 CA02 DA02 EA06 FA03 FA34 4K022 AA02 AA31 AA41 BA14 BA16 DA01 EA04 4K044 AA06 AB10 BA06 BA17 BB03 BB03 BC02 BC05 BC12 CA15 CA16 CA53

Claims (8)

[Claims] 1. A pump member having a metal plating layer formed on a base material and a resin layer formed on the metal plating layer, wherein the resin layer is made of a fluororesin. A pump member characterized by. 2. An intermediate layer is provided between the metal plating layer and the resin layer.
The described pump member. 3. The pump member according to claim 1, wherein the metal plating layer is formed by electroless plating. 4. The pump member according to claim 1, wherein the resin layer is formed by electrodeposition coating. 5. The pump member according to claim 1, wherein the metal plating layer is made of nickel. 6. The pump member is a rotor based on an aluminum alloy as a base material.
The pump member according to any one of 1. 7. A rotor having a nickel layer formed by electroless plating on a base material made of an aluminum alloy, and a fluorine resin layer formed by electrodeposition coating on the nickel layer. Characteristic turbo molecular pump. 8. The surface treatment layer, wherein the first layer is a nickel layer formed by electroless plating, and the second layer is a resin layer formed by electrodeposition coating of a fluororesin. .