JPH08141305A - Gas trap - Google Patents

Abstract

PURPOSE: To provide a gas trap provided with stabilized exhaust function for the stable operation for a long period of time by removing mechanically a solid component collected in a gas flow path. CONSTITUTION: Gas exhausted from a reaction chamber is flowed from an inflow opening 4 of a gas trap, passing through a space formed around a helical blade 9, and exhausted out of an exhaust outlet 5. At that time, a wall 10 of a main body 1 is cooled by a water-cooling jacket 6, and a component to be solidified by the temperature in the gas is made to adhere to the inner face of the wall 10. An adhered material is scraped off to the lower face side of the blade 9 by rotating a rotating shaft 8 and stored in a solid storage chamber 2. Thus stabilized exhaust without the accumulation of solids in an exhaust flow path is carried out, and no backflow of solids is generated to prevent generation of troubles such as a bite and others in a vacuum pump.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a trap for trapping solids used in an exhaust system such as a semiconductor manufacturing apparatus.

[0002]

2. Description of the Related Art In the exhaust system of semiconductor manufacturing equipment,
In the process of exhausting, the gas solidifies, blocking the pipes,
Accumulation inside the vacuum pump has been a problem. Therefore, as shown in FIG. 2 or 3, in the middle of the exhaust system,
A method has been adopted in which a trap for intensively solidifying and collecting gas is provided to efficiently maintain an exhaust system.
As this trap, for example, as shown in FIG. 4, a trap in which a filter is interposed in the exhaust passage is used.

[0003]

However, in the prior art, since the trapped solid which is a part of the exhaust system, that is, the solid collected in the filter in the example of FIG. 4, is deposited as follows. There are some drawbacks. (1) Since the collected deposits narrow the exhaust flow path (become clogged in the example of FIG. 4) and become a resistance to gas flow, the exhaust capacity on the upstream side of this becomes lower. (2) The collected solid matter flows backward due to exhaust pulsation and pollutes the upstream side. (3) The collected solid matter falls into a lump and falls, causing problems such as biting in the vacuum pump.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems by mechanically removing the solid matter collected in the gas passage. According to the invention of claim 1, in an exhaust system such as a semiconductor manufacturing apparatus, there is provided a trap for collecting a gas solidified in the system as a solid matter, which mechanically removes the solid matter collected in a gas flow path. It has a solid matter removing member. The invention according to claim 2 further has a solid material storage chamber separate from the gas flow path for storing the removed solid material. According to a third aspect of the present invention, the solid matter removing section is provided with a wall section for forcibly solidifying the gas that solidifies in the exhaust system at a predetermined location. According to the invention of claim 4, the wall portion is forcibly cooled.

According to a fifth aspect of the present invention, the wall portion is formed vertically or inclined with respect to the vertical direction. According to a sixth aspect of the present invention, the solid matter removing portion has a scraping member that scrapes off the deposits on the surface of the wall portion. According to the invention of claim 7, a flow path for guiding the gas to the wall portion is formed by the scraping member. According to an eighth aspect of the present invention, the wall portion is formed in a substantially cylindrical surface shape, and the scraping member is rotated about the center line of the wall portion as an axis.

[0006]

In the first aspect of the invention, the gas that solidifies in the exhaust system is trapped as a solid by the trap, and this is mechanically removed by the solid removal member.
According to the second aspect of the invention, the removed solid matter is stored in a solid matter storage chamber different from the gas passage. Claim 3
In the invention of, in the wall portion of the solid removal portion,
The gas that solidifies in the exhaust system is forcibly solidified. In the invention of claim 4, the wall portion is forcibly cooled to forcibly solidify the components in the gas that are likely to be solidified in the gas in the exhaust system.

In the invention of claim 5, since the wall portion is formed vertically or inclined with respect to the vertical direction, the solid matter removed by the removing member falls,
Or it is dropped along the wall and removed. According to the sixth aspect of the invention, the adhering matter is scraped off and removed by the scraping member of the solid matter removing section. In the invention of claim 7, the gas is guided to the wall portion by the flow path formed by the scraping member, and the gas component is solidified there. In the invention of claim 8, the deposit is scraped from the surface of the cylindrical wall by rotating the scraping member with the center line of the wall as an axis.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A gas trap according to an embodiment of the present invention will be described below with reference to FIG. This gas trap is used by being installed at a predetermined position of the exhaust system of FIG. 2 or 3, and has a substantially cylindrical shape, and the upper body 1 and the lower storage chamber 2 have a flange 3 It is configured to be connected via.

The main body 1 is made of a material having a relatively high thermal conductivity such as metal, a gas inlet 4 is provided in the upper portion, a gas outlet 5 is provided in the lower portion, and a water cooling jacket 6 is provided outside. Therefore, the wall of the main body 1 is kept at a predetermined temperature.

A rotary shaft 8 is provided through the top plate 7 of the main body 1 along the central axis of the main body 1, and its outer end is connected to a drive device (not shown). A spiral blade (scraping member) 9 having an outer diameter substantially the same as the inner diameter of the main body 1 is attached to a portion of the rotary shaft 8 between the inflow port 4 and the discharge port 5 inside the main body 1. With the rotation of the
The deposits on the surface of the inner wall 10 are scraped off. The blade 9 is made of a material that is not easily deteriorated by the temperature of the gas and has low reactivity with the gas. The surface of the blade 9 is smoothly finished so that solid matter does not easily adhere thereto.

The operation of the gas trap thus constructed will be described below. In the exhaust system shown in FIG. 2 or FIG. 3, the gas discharged from the reaction chamber flows in through the inlet 4 of the gas trap after or before passing through the vacuum pump, and passes through the space between the spiral blades 9. It is discharged from the discharge port 5. In this process, since the wall 10 of the main body 1 is cooled to a predetermined temperature by the water cooling jacket 6, the component in the gas that solidifies at this temperature solidifies on the inner surface of the wall 10,
Adhere to.

The attached matter is scraped off by the lower surface side of the blade 9 by rotating the rotary shaft 8, and directly or after sliding down on the upper surface of the blade 9, it falls into the solid material storage chamber 2 and is stored therein. To be done. The rotating shaft 8 may be rotated constantly or intermittently,
You may make it suitably according to the amount of deposits, etc. When the exhaust system is not operating, the falling solids contained in the storage chamber 2 are removed by appropriately removing the flange 3 and
To remove from.

In the gas trap of the above-mentioned embodiment, the spiral vane 9 forms a gas flow path inside the main body 1, which prolongs the residence time inside the main body 1 and the water cooling jacket. Wall 10 cooled by 6
Since the contact time with is also long, it is possible to efficiently remove the components that are likely to be solidified in the gas. In order to further improve this efficiency, in order to increase the contact ratio with the wall 10, a cylinder may be provided around the rotary shaft 8 so that the gas flow path is formed only on the wall side.

In this embodiment, since the spiral blade 9 attached to the rotary shaft 8 is used as the scraping member, the adhered matter can be scraped off with a relatively small driving force, and the amount of the adhered matter on the blade 9 itself can be scraped. Few. Further, in the above-described embodiment, since the main body 1 is installed vertically, it is easy to scrape the adhering matter from the wall 10, and the installation of the rotary shaft 8 and the connection with the drive device are also easy. According to the above, the main body 1 may be installed by inclining. As the scraping member, a member having a blade-shaped portion parallel to the axis close to the wall surface of the rotation axis may be adopted, or a disk-shaped member may be vertically moved along the axis.

[0015]

As described above, according to the first aspect of the present invention, stable exhaust capacity can be obtained without depositing solid matter in the exhaust passage, and long-term stable operation of exhaust system equipment becomes possible. At the same time, the reverse flow of the collected solid matter due to the exhaust pulsation in the exhaust flow path is reduced, and further, it is possible to obtain an excellent effect such that problems such as biting in the vacuum pump are prevented. According to the invention of claim 2, the size of the chamber for storing the solid matter can be determined regardless of the structure of the portion for solidifying and collecting the gas, and the maintenance cycle of the trap can be lengthened. According to the invention of claim 3, the gas component to be solidified is efficiently removed,
Problems due to solidification in the subsequent process are reduced.

According to the fourth aspect of the present invention, the wall portion is forcibly cooled, and the component in the gas which is likely to be solidified due to the temperature decrease in the subsequent step in the exhaust system is forcibly solidified and removed. According to the invention of claim 5, since the solid matter removed by the removing member falls or falls along the wall,
It has a simple structure and can be easily removed outside the exhaust system. According to the invention of claim 6, since the adhering matter is scraped off by the scraping member of the solid matter removing section, the adhering matter can be surely removed. According to the invention of claim 7, since the flow path is formed by the scraping member, the solidified component can be efficiently removed with a simple structure. According to the invention of claim 8, the structure for mounting and driving the main body of the trap and the scraping member is simplified, and moreover, the adhered substances are reliably removed.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing a gas trap according to an embodiment of the present invention.

FIG. 2 is a diagram showing an exhaust system in which a gas trap is used.

FIG. 3 is also a diagram showing another example of an exhaust system in which a gas trap is used.

FIG. 4 is a sectional view schematically showing a conventional gas trap.

[Explanation of symbols]

 1 Trap Main Body 2 Reservoir Chamber 4 Gas Inlet 5 Outlet 6 Water Cooling Jacket 8 Rotating Shaft 9 Blade (Scraping Member) 10 Wall

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naoya Hanafusa 11-11 Haneda-Asahicho, Ota-ku, Tokyo Inside the EBARA CORPORATION

Claims (8)

[Claims] 1. An exhaust system such as a semiconductor manufacturing apparatus,
A trap for collecting a gas that solidifies in a system as a solid matter, which has a solid matter removing section for mechanically removing the collected solid matter in a gas flow path. 2. The gas trap according to claim 1, further comprising a solid material accommodating chamber separate from the gas flow path for accumulating the removed solid material. 3. The gas according to claim 1 or 2, wherein the solid matter removing portion has a wall portion for forcibly solidifying the gas that solidifies in the exhaust system at a predetermined location. strap. 4. The gas trap according to claim 3, wherein the wall portion is forcibly cooled. 5. The wall portion is formed vertically or inclined with respect to the vertical direction.
Or the gas trap according to 4. 6. The gas trap according to claim 3, wherein the solid matter removing portion has a scraping member that scrapes off the deposits on the surface of the wall portion. 7. The gas trap according to claim 6, wherein the scraping member forms a flow path for guiding gas to the wall portion. 8. The mower according to claim 6, wherein the wall portion is formed in a substantially cylindrical surface shape, and the scraping member is adapted to rotate about a center line of the wall portion. strap.