Fluid handling – With cleaner – lubrication added to fluid or liquid sealing... – Cleaning or steam sterilizing
Reexamination Certificate
1998-05-08
2001-04-03
Shaver, Kevin (Department: 3754)
Fluid handling
With cleaner, lubrication added to fluid or liquid sealing...
Cleaning or steam sterilizing
C137S602000, C137S884000
Reexamination Certificate
active
06209571
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a process gas supply unit used in a semiconductor manufacturing process and, more particularly to a process gas supply unit provided with a process gas supply valve, a purge valve, a check valve and the like.
2. Description of Related Art
A process gas supply unit for supplying process gas such as etching gas in a semiconductor manufacturing process has been developed. For example, as shown in FIG. 10, Japanese Published Unexamined Patent Application No. 5-172265 discloses a block manifold provided with two open/close valves 1, 2 in which an input passage 4 through which the input port of the open/close valve communicates with an external entry port 6, an output passage 5 through which the output port of the open/close valve 1 communicates with an external exit port 7 and a communicating passage 8 through which the output port of the open/close valve 2 communicates with the output passage 5.
However, for example, in a flow chart of a process gas supply shown in FIG. 7, the output port of a supply valve 13 and the output port of a purge valve 12 are connected to the entry port of a mass flow controller 11. The input port of the supply valve 13 is connected to a process gas source. The input port of the purge valve 12 is connected to an inert gas source for purge gas via a check valve 14. The check valve 14 is provided for preventing the reverse flow of the process gas into the inert gas source.
Since a passage through which the purge valve 12 communicates with the check valve 14 in series need to be connected to a process gas line in such a gas supply line, the passage could not be formed in one block manifold according to the technique used in the block manifold disclosed in Japanese Published Unexamined Patent Application No. 5-172265.
Therefore, according to a related art, as shown in FIG. 11, the gas supply line has been constructed by providing joints on both sides of each of a mass flow controller 11, a supply valve 13, a purge valve 12 and a check valve 14 and by butt-welding (A) pipes between the joints.
However, the process gas supply line according to the related art has the following problems.
(1) Although the semiconductor manufacturing apparatus needs to be reduced in size and integrated, the gas supply line shown in FIG. 11 needs large space and hence is opposite to reduction in size and integration.
Further, since many weld portions are made, corrosion resistance is reduced and particles might be generated. When the supply valve 13, the purge valve 12 and the check valve 14 are maintained and are replaced, the joints need to be separated and replaced, which is not suitable for maintenance.
(2) On the other hand, according to the technique disclosed in Japanese Published Unexamined Patent Application No. 5-172265, if the process gas supply line is used only for forming the flow of the process gas, it is possible to mount a plurality of units on a block manifold and to form a passage communicating with the inside of the block manifold. However, it is difficult to connect a passage through which the purge 12 communicates with the check valve 14 in series to this process gas supply line because it produces the other problem.
In other words, since two passages need to be formed in the block manifold and, in this case, extra openings are necessarily made and hence stoppers for closing the extra openings are required, which produces a problem that these stopper might produce new particles. Further, when the process gas is replaced by the purge gas, the process gas remains near the stoppers, which reduces a yield of the semiconductor.
SUMMARY OF THE INVENTION
It is an object of the present invention to solve the above-described problems and to provide a compact integrated process gas supply unit which a purge valve communicating with a check valve in series is connected to a process gas flow.
To accomplish the above-described object, the process gas supply unit according to the present invention has the following constitution:
(1) A process gas supply unit for a semiconductor manufacturing apparatus comprises a supply valve for supplying process gas to the semiconductor manufacturing apparatus, a purge valve for supplying inert gas, a check valve disposed in a passage between an inert gas source and the purge valve and a common manifold on which the supply valve, the purge valve and the check valve are mounted.
(2) In the common manifold described above in (1) are formed a process gas input passage through which the input port of the supply valve communicates with a process gas external entry port, a process gas output passage through which the output port of the supply valve communicates with a process gas external exit port, a purge output passage through which the output port of the purge valve communicates with the process gas output passage, a check valve output passage through which the input port of the purge valve communicates with the output port of the check valve and a purge gas input passage through which the input port of the check valve communicates with a purge gas external entry port.
(3) A process gas supply unit described in (1) further comprises a vacuum valve which is connected to a vacuum pump and is mounted on the manifold.
(4) In the manifold of the process gas supply unit described in (3) are formed a vacuum output passage through which the output port of the vacuum valve communicates with the process gas output passage and a vacuum input passage through which the input port of the vacuum valve communicates with a vacuum external entry port.
(5) The check valve output passage of the process gas supply unit described in (1) or (3) is shaped nearly like a letter V.
Next, the action of the process gas supply unit according to the present invention having the above-described constitution will be described.
Since each of the supply valve, the purge valve, the check valve are mounted by four bolts on the upper side of the block manifold in the above-described process gas supply unit, it can be mounted or removed individually.
Further, since the output port of the purge valve communicates with the output passage of the process gas, the output port of the supply valve and a mass flow controller can be replaced by the purge gas.
In this respect, the check valve is disposed next to the purge valve in the block manifold and the purge gas input passage of the check valve bypasses the output passage of the process gas in a slanting direction and intersects the output passage of the process gas in a torsional relation by a lower side block and a port is formed upward, whereby the check valve can be mounted on and removed from the upper side of the manifold. Further, a purge gas supply tube and the like can be mounted on and removed from the upper side of the manifold by upwardly forming the purge gas external entry port.
Further, in another process gas supply unit, a check valve output passage through which the input port of the purge valve communicates with the output port of the check valve is shaped nearly like a letter V and hence both ports can be connected at a short distance. Furthermore, since only one bending portion can be made, it is unlikely that the process gas remains in the check valve output passage even if the process gas flows in reverse and is stopped by the check valve. Still further, since the V-shaped passage can be made by drilling two slanting holes in opposite directions, it is easy to make the passage and to clean it after it is made, whereby the fine chips produced by drilling, oil and the like can be fully removed.
In another process gas supply unit, the vacuum valve is disposed next to the check valve in the block manifold and hence the vacuum valve can be mounted on and removed from the upper side of the block manifold by four bolts.
Further, the vacuum input passage of the vacuum valve bypasses the output passage of the process gas in a slanting direction and intersects the process gas output passage in a torsional relation by a lower side seco
Inagaki Toshiyasu
Itoh Masahito
Bastianelli John
CKD Corporation
Finnegan Henderson Farabow Garrett & Dunner L.L.P.
Shaver Kevin
LandOfFree
Process gas supply unit does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process gas supply unit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process gas supply unit will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2460899