JPH01267391A - Vacuum pump - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vacuum pump, and particularly to a vacuum pump suitable for preventing reaction products caused by process gas from adhering to an exhaust path.

[Conventional technology]

In recent years, various vacuum pumps have been proposed in order to produce clean genuine products in semiconductor manufacturing equipment, etc.;
There is a technology described in the publication No.

This type of vacuum pump generally compresses the gas sucked in from the intake port sequentially through a flow path made up of the rotor and stator that make up the pump mechanism, and then exhausts it to the atmosphere from the exhaust port. There is.

In addition, in the vacuum pump of this stock,
As shown in Publication No. J197, when process gas handled in semiconductor manufacturing equipment causes substances that tend to solidify in the gas to accumulate in the passages, it is easy to remove the deposits. I hope.

There are devices that facilitate disassembly and assembly.

[Problem to be solved by the invention]

In the above-mentioned conventional technology, when reaction products are deposited in the process gas flow path, the gas flow path is closed, and the device is disassembled to remove the deposit. There was a problem in that the operation of semiconductor manufacturing equipment and the like connected to the pump had to be stopped, resulting in a decrease in work efficiency.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vacuum pump that solves the problems of the prior art and can prevent the gas exhaust path from being blocked by reaction products attached thereto.

[Means to solve the problem]

The above object is achieved by providing induction heating means in the gas exhaust path.

[Effect]

The induction heating means installed in the exhaust passage is composed of a heating coil and a high-frequency power source. When a high-frequency current is applied to the heating coil, magnetic lines of force are generated, and the magnetic lines of force cause numerous waves to be generated on the metal exhaust passage wall. An eddy current is generated, which generates heat because the metal has electrical resistance.

For this reason, 1 reaction product vaporizes on the exhaust passage wall, so 1
It is possible to prevent the exhaust passage from being blocked due to adhesion of reaction products.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional side view showing one embodiment of the present invention.

FIG. 2 is an enlarged sectional view of the main parts of the embodiment shown in FIG. 1.

The vacuum pump of the embodiment shown in FIG. 1 includes a pump housing 1, a pump mechanism 7, a motor housing 10,
It is configured to include a motor 11, a drive shaft 14, induction heating means, and an oil reservoir 19.

The pump housing 1 includes a housing body 2, a first end plate 3 attached to one end of the housing body 2,
The second end plate 4 is attached to the other end. The first end plate 3 is provided with an air inlet 5, which communicates with semiconductor manufacturing equipment (not shown) such as an aluminum dry etching equipment for semiconductor devices. An exhaust passage 6 is provided across the second end plate 4 and the final stage of the pump mechanism 7, and an exhaust port 6' is provided at the end of the second end plate 4.

The pump mechanism 7 includes a stator 8 fixed inside the pump housing 1, and a rotor 9 configured with a plurality of blades connected together and rotatably arranged inside the stator 8.
It has a multi-stage structure.

The motor housing 10 is located at the pump housing 1.
It is fixed to the end plate 3 of 2.

The motor 11 includes a stator 12 fixed inside a motor housing 10, and a rotor 13 rotatably disposed inside the stator 12.

The drive shaft 14 has a bearing 15 built into the second end plate 4 of the pump housing 1.

The ratio bearing mount is fixed to the end of the motor housing 10 and is supported by a bearing 15' built into the plate 16. This drive shaft 14 is rotationally driven by the motor 11 and rotates the rotor 9 of the pump mechanism 7.

As shown in detail in FIG. 2, the induction heating means includes a heating coil 1 provided in the exhaust passage 6 near the exhaust port 6'.
7 and a high frequency power source 18. The high frequency power source 18 is configured to heat one heating coil 17 by electromagnetic induction.

The oil reservoir 19 is fixed to the plate 16 with the bearing receiving plate. This oil reservoir 19 contains lubricating oil 20 for bearings.

The vacuum pump of the above embodiment is operated in the primary operation...
act.

A drive shaft 14 is rotationally driven by the motor 11.

As the rotor 9 of the pump machine 7 is rotated by the drive shaft 14, the gas sucked in from the intake port 5 is gradually pressured in the flow path formed by the stator 8 and rotor 9. ! It is discharged to the atmosphere from the exhaust passage 6t and the exhaust port 6'.

In the fc exhaust process mentioned above, the gas becomes high temperature in the part where the rotor 9 is rotating, but the heat escapes to the housing body 2 of the pump housing 1 and the second end plate 4 near the exhaust path 6. , the temperature of the gas decreases. For this reason, if the suction side of the vacuum pump is connected to, for example, an aluminum dry etching device for semiconductor devices, aluminum chloride (AtC6,) is produced as a reaction product after etching.

FIG. 3 is a vapor pressure diagram of AtC15.

As shown in Figure 3, kLcLs becomes solid at temperatures below about 180C near atmospheric pressure.

The reaction product passing through the flow path is cooled on the inner wall of the exhaust path 6 and forms a layer on the inner wall.

Therefore, a high frequency current is passed through the heating coil 17 through the Takaoka am source 18 of the 8-conductor heating means. When a high frequency current is passed through the heating coil 17, a magnetic edge is generated, and the magnetic edge generates countless eddies on the wall of the exhaust passage 6 of the metal F4 table, and heat is generated because the metal has 11L air resistance. do. This is because the temperature of the exhaust passage 6 increases due to electromagnetic induction heating by the heating coil 17.

The adhering substance, htcts, is vaporized. therefore,
The reaction product builds up in the exhaust path 6.

It becomes possible to prevent the exhaust passage 6 from being blocked due to the adhesion of this reaction product.

〔Effect of the invention〕

According to the present invention as described above, the induction heating means is provided in the gas exhaust passage, and the reaction products adhering to the exhaust passage wall are vaporized by electromagnetic induction heating. This has the effect of preventing clogging of the exhaust passage due to the layering.

[Brief explanation of the drawing]

Figure 1 shows the features of the present invention! - Longitudinal side view showing a further example. FIG. 2 is an enlarged sectional view of the main part of the *9 example shown in FIG. 1, and FIG. 3 is a vapor pressure fan circuit of ALCLs. 1...Pump housing, 5...Intake port, 6...
exhaust path. 61...Exhaust port, 7...Pump mechanism, 10...Motor housing, 11...Motor, 14...Drive shaft, 17...Heating coil forming induction heating means,
18...Same as ^ frequency power supply.

Claims (1)

[Claims] 1. The rotor of the pump mechanism is rotated by the motor via the drive shaft, gas is sucked in through the intake port provided in the pump housing, the pump mechanism pressurizes the rotor to approximately atmospheric pressure, and the gas is transferred to the pump mechanism provided in the pump housing. In a vacuum pump that exhausts air from the exhaust path to the atmosphere through the exhaust port,
A vacuum pump characterized in that the exhaust path is provided with induction heating means.