JP3071320B2 - Vacuum equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for blocking the inflow of air into a space where pressure can be reduced.

[0002]

2. Description of the Related Art For example, in the case of a semiconductor manufacturing process, various decompression processing apparatuses for processing an object to be processed such as a semiconductor wafer in a decompression space are widely used. Once the atmosphere, particularly atmospheric oxygen and moisture, once flows into this kind of decompression processing space, the time required to exhaust the decompression processing chamber to a predetermined degree of vacuum becomes enormous, and the process cycle deteriorates. In particular,
In recent years, the miniaturization and densification of semiconductor elements have been advanced, and it has been necessary to lower the concentration of impurities such as oxygen and moisture in the processing space. Therefore, it is required to lower the back pressure before starting the process. Therefore, the evacuation time becomes longer and the process cycle is further deteriorated.

Conventionally, a process chamber and a load lock chamber are connected via a gate valve in order to prevent air from flowing into a process space. After the atmosphere around the object to be processed is replaced with a vacuum atmosphere from the atmosphere in the load lock chamber, the object is to be carried into the process chamber. In addition, before the load lock chamber is opened to the atmosphere, the inside of the load lock chamber is set to be more positive than atmospheric pressure.

[0004]

SUMMARY OF THE INVENTION The present inventors have conducted experiments on how the subsequent evacuation time differs depending on whether a relatively large amount of air flows into a vacuum chamber or not. To distinguish between the two, gate valves having different opening diameters were connected to two vacuum chambers having the same capacity of 10 liters. As a common condition before starting exhaust,
Set the inside of the vacuum chamber to 3 × 10 ⁻⁸ Torr;
Purging N ₂ gas at a pressure of 5 to 2.5 kg / Cm ² ;
After a sufficient time, the gate valve was opened for 5 minutes while performing N ₂ purge. Thereafter, evacuation time measurement was started after closing the gate valve, and the evacuation time was measured by rough evacuation and high evacuation until the pressure in the vacuum chamber reached 1 × 10 ⁻⁷ Torr. When a gate valve having an opening diameter of 100 mm was used, the evacuation time was about 40 minutes. In the case where the diameter of the gate valve was extremely narrowed and the condition in which the atmosphere hardly flowed was used by utilizing the fact that the inside of the vacuum chamber was at a higher pressure than the atmosphere, the exhaust time was about 8 minutes.

As described above, it can be understood how the evacuation time is prolonged when the air flows into the vacuum chamber.
An opening of a certain size must communicate with the atmosphere, and in such a case, a device for preventing the air from flowing into the vacuum chamber has been desired.

In the conventional apparatus, even if the load lock chamber is set at a positive pressure than the atmospheric pressure, the vicinity of the outlet is
It is considered that the flow rate of the N ₂ gas is insufficient, and the flow of the N ₂ gas is disturbed by the friction of the inner wall surface, so that much air flows in along the inner wall surface.

Accordingly, it is an object of the present invention to provide an apparatus capable of further preventing the air from flowing into a space where pressure can be reduced from the above-mentioned viewpoint, and thereby reducing the exhaust time. It is in.

It is a further object of the present invention to prevent the inflow of air, thereby preventing the occurrence of turbulence in a space where pressure can be reduced and causing a pressure change in the space due to the occurrence of turbulence. It is an object of the present invention to provide a device which can prevent the inflow of the atmosphere more reliably and reduce the exhaust time.

[0009]

According to a first aspect of the present invention, there is provided a vacuum apparatus having an exhaust means, a gas supply means, and an opening / closing port provided between the atmosphere and a decompressible space. In a vacuum device for loading or unloading a transferred object with the atmosphere,
Is disposed on the atmosphere side than the closure, the passage of the closure to the subsequently formed the object to be transferred, the transportable prior Symbol passage
Provided along the transport direction of the carrier,
A plurality of ejection ports for forming a gas curtain of several stages, the double
The number of the ejection ports is each an open end, and the
Guide the purge gas toward each of the jet ports.
A plurality of slits, each of which is opposed to the plurality of ejection ports;
At a position protruding from the inner wall of the passage,
Purge gas ejected from each of the
A guide plate for guiding toward the atmosphere side;
Each of the slits of the
Having an inclination angle θ (θ> 0) inclined toward the air side,
The inclination angle of the slit farther from the atmosphere side is
The slit is closer to the air side than the inclination angle of the slit .

[0010] The vacuum apparatus according to the second aspect of the present invention comprises:
A vacuum device that has an exhaust unit, a gas supply unit, and an opening and closing port provided between the air and a vacuum device that loads or unloads a transferred object between a space that can be depressurized and the atmosphere, is disposed on the atmosphere side, a passage of the closure to the subsequently formed the object to be transferred, in the conveying direction of the object to be transferred before Symbol passage
A multi-stage gas curtain provided with purge gas
A plurality of ejection ports to form a down, the plurality of ejection ports it
And the purge gas from the gas supply means.
A plurality of slits for guiding
And the most slit from the atmosphere side of the plurality of slits.
The distant slit is a vertical slit parallel to the vertical plane of the passage.
Slits, each of the plurality of slits other than the vertical slit being opposed to a vertical surface of the passage.
And the inclination angle θ (θ> 0) inclined toward the atmosphere side
The inclination angle of the slit at a position farther from the atmosphere side
Is larger than the inclination angle of the slit close to the atmosphere side .

The vacuum apparatus according to the third aspect of the present invention is
The plurality of jets in the passage according to claim 1 or 2,
On the inner wall surface facing the inner wall surface where the outlet is formed
Is formed in an area intersecting with the gas curtain,
The gas curtain is tilted in the direction in which the gas curtain is formed.
An inclined portion allowing the formation of a metal plate;
Extending from the end on the air side, and
And a projecting portion projecting from the opening end to the atmosphere side .

[0012] A vacuum apparatus according to a fourth aspect of the present invention comprises:
4. The device according to claim 1, wherein:
The gas-side open end and the gas downstream of the gas curtain.
Position along the width direction of the passage at a position where the pressure
It is characterized in that a plurality of straightening plates arranged in parallel at intervals are provided . The vacuum apparatus according to the invention described in claim 5 is:
5. The passage according to claim 4, wherein
A corrugated plate is provided in the inner area, and a vortex is closed in the concave portion of the corrugated plate.
The direction parallel to the line connecting the vertices of the corrugated plate
Laminar flow from the inside of the passage to the atmosphere side along
Is formed.

[0013]

According to the first aspect of the present invention, all the ejection ports are provided.
Each gas curtain of multiple stages formed by blowing from
Tilted to the atmosphere side by the lit inclination angle and the guide plate
Gas formed and formed at a position far from the atmosphere
The curtain is a gas curtain formed near the atmosphere.
The inclination angle is larger than that of This
Air can be reliably prevented from entering the passage.
it can.

In order to carry in / out the object to be conveyed, the opening / closing opening between the vacuum device and the atmosphere is set in a state in which the pressure in the decompression space is set to be higher than the atmosphere by the purge gas supplied from the gas supply means. Open. At this time, by purging the purge gas from the discharge port in the passage connected to the opening and closing port, the pressure in the passage is set to be more positive than the atmosphere by the purge gas. Thereafter, the conveyed object is carried into or out of the vacuum device through this passage. The vacuum device and the passage are set at a positive pressure with respect to the atmosphere with the purge gas, and the atmosphere does not flow in.

By introducing the purge gas directly into this passage,
This contributes to increasing the degree of positive pressure on the side that opens to the atmosphere, rather than increasing the flow rate of purge gas to a space where pressure can be reduced.

[0016] According to the second aspect of the present invention, whether the air side is
Spurts from multiple other spouts except the farthest spout
Each gas curtain of multiple stages to be formed, the inclination of the slit
It is formed to incline toward the atmosphere according to the angle. Furthermore, the atmosphere
Ejected from the outlet with the vertical slit furthest from the side
From the gas curtain in multiple stages
The inner passage is also set at positive pressure. Due to these actions
Air can be reliably prevented from entering the passage.
it can.

In this case, by providing the jet port in a direction to form a purge gas curtain directed to the atmosphere side,
The flow of the purge gas that has become positive pressure can be pushed out by the gas curtain, and more strict inflow of air can be prevented.

According to the third aspect of the present invention, in the passage,
Since the purge gas is ejected from the ejection port,
Of the inner wall surface facing the inner wall surface
Gas pressure is lowest and air flows from this region.
Easy to sink. In the area where the flow of the purge gas is weak, the vortex
A flow is formed and if this vortex is formed above the opposing wall
If air is trapped in the passage of the transported object,
Flow will be formed. In claim 3, the inclined portion and
By forming a projecting part, such eddy currents
Guides should be formed on protrusions that do not directly interfere with the transport path.
With this, it is possible to transport the transported object without being related to the vortex.
This prevents the entrainment of the atmosphere.

According to the invention described in claim 4, the gas car
At the position where the gas pressure on the downstream side of the balance
By arranging a plurality of straightening plates in parallel at intervals along the direction, a smooth flow can be formed on the atmosphere side even in the downstream area of the gas curtain.

According to the invention described in claim 5, a plurality of alignments are provided.
By the corrugated plate provided in the area inside the passage than the flow plate,
The vortex can be confined in the concave portion of the corrugated plate. So
As a result, in the direction parallel to the line connecting the vertices of the corrugated plate
Along the laminar flow from the inside of the passage toward the atmosphere.
Can be achieved.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a semiconductor wafer decompression processing system will be specifically described with reference to the drawings.

First, the overall outline of the apparatus of this embodiment will be described with reference to FIG. In FIG. 1, a process chamber 10 is a decompression processing device for performing etching, ashing, ion implantation, or various film forming processes. Load lock chambers 12 and 14 on the carry-in side and carry-out side are connected to both sides of the process chamber 10 via gate valves 16 and 16, respectively. Further, each of the load lock chambers 12 and 14 is connected to a gate valve 18 for shutting off the atmosphere. After the gate valves 16 and 18 on both sides of the load lock chamber 10 are closed, the atmosphere is replaced from the atmospheric pressure to a vacuum atmosphere. After the pressures in the chambers 10 and 12 become substantially equal, the gate valve 16 therebetween is opened. As a result, the semiconductor wafer is carried into the process chamber 10. After the completion of the decompression process in the process chamber 12, the gate valve 16 is opened, and the semiconductor wafer is loaded into the load lock chamber 14 on the unloading side. Thereafter, the gate valve 16 is closed, the atmosphere inside the load lock chamber 14 is replaced from a vacuum atmosphere to a positive pressure than the atmospheric pressure, and then the gate valve 18 on the unloading side is opened to unload the wafer.

Each of the chambers 10 to 14 can be evacuated, and a vacuum pump 20 is connected to each of the chambers 10 to 14. Further, each chamber 10
To 14 can be raised to atmospheric pressure or a pressure around the atmospheric pressure.
It is possible to purge ₂ . Further, in the apparatus of this embodiment, the above-mentioned pressure reduction processing system further connects purge blocks 40, 40 at two positions before and after adjacent to the atmosphere. The purge blocks 40 can also purge nitrogen gas N ₂ . For this reason, a common N ₂ gas supply pipe 22 is provided in each part, and this supply pipe 22 is branched and connected to each of the chambers 10 to 14 and the purge blocks 40, 40 as a branch pipe 24. In the middle of each branch pipe 24, a mass flow controller 26 for adjusting the flow rate of nitrogen gas and a valve 2 for interrupting the pipe line are provided.
8 and a filter 30 capable of trapping particles having a diameter of, for example, 0.01 μm or more.

Next, details of the purge block 40 will be described with reference to FIGS. The purge block 40 has two side walls 42a, 4 facing each other on the left and right.
2a, a bottom wall 42b, and an upper wall 42c, which define a passage 42 for the semiconductor wafer. This passage 42
Is formed with a flange 44 at one end. This flange 44 is connected to the valve-side flange 18a of the gate valve 18.
And bolts and nuts. A purge box 46 that forms a space 48 with the upper wall 42c is fixed to, for example, the upper wall 42c of the purge block 40. The purge box 46 contains the branch pipe 24.
Are connected to each other so that nitrogen gas can be introduced into the inside.

Further, the upper wall 42c of the purge block 40
The first to fourth slits 50 to 50 penetrate from the upper surface to the lower surface and open over substantially the entire width direction of the passage 42.
56 are formed. Each of the slits 50 to 56 connects a space 48 in the purge box 46 with the passage 42,
This is for purging nitrogen gas from the space 48 toward the passage 42. The first slit 50 is formed as a first-stage slit closest to the external atmosphere. The first slit 50 is formed to incline by an angle θ _{1 with} respect to a vertical axis toward the external atmosphere as it goes from the space 48 toward the passage 42. The second and third slits 52 and 54 are formed as the second and third slits, respectively, and are similarly formed at angles θ ₂ and θ _{3 with} respect to the vertical axis. The fourth slit 56 is formed horizontally with the vertical axis. First to third slits 50 to 5
The inclination angles θ _{1 to} θ ₃ of 4 have a larger angle as the distance from the external atmosphere increases, that is, a relationship of θ ₁ <θ ₂ <θ ₃ .

In the passage 42 of the purge block 40, first to third guide plates 58 to 62 projecting inward from the side walls 42a, 42a by a predetermined length are fixed. The first to third guide plates 58 to 62 are arranged at positions facing the first to third slits 50 to 54, and supply nitrogen gas ejected from the slits 50 to 54 to the inclination angle θ of each slit. it is for guiding along ₁ through? _3. The upper end of each of the guide plates 58 to 62 is substantially the upper wall 42c.
, But the lower end of the bottom wall 42b
It ends in a position that does not reach to. The effective passage width of the semiconductor wafer in the passage 42 of the purge block 40 is, as shown in FIG.
The inner width W is 58.

Next, the shape of the bottom wall 42b of the passage 42 will be described. The open end of the bottom wall 42b is formed as an inclined surface 64 that is inclined downward toward the tip. Further, the tip of the inclined surface 64 is connected to a horizontal projecting surface 66 that projects horizontally from the opening of the purge block 40 toward the outside atmosphere. In a region formed by the inclined surface 64 and the horizontal protruding surface 66, a plurality of rectifying plates 68 which are arranged in parallel at regular intervals in the width direction of the purge block 40 and whose upper end protrudes from the bottom wall 42 b are provided. Is provided. Further, a corrugated plate 70 formed in a corrugated plate shape is provided on the upper surface of the bottom wall 42b in a region further inside the inner ends of the plurality of rectifying plates 68 over the entire width direction of the purge block 40. Are located. Note that various members constituting the purge block 40 are formed of, for example, stainless steel, and the members are interconnected by, for example, spot welding.

Next, the operation will be described.

A case where a semiconductor wafer is loaded into the process chamber 10 will be considered. At this time, the gate valves 16 and 18 on both sides of the load lock chamber 12 on the loading side are closed beforehand, and the inside of the load lock chamber 12 is set to a positive pressure than the atmospheric pressure. To this end, the load lock chamber 12 is purged with nitrogen gas through the gas supply pipe 22 and the branch pipe 24. If the gate valve 18 is opened after the interior of the load lock chamber 12 is set to a positive pressure, the atmosphere does not flow into the load lock chamber 12 of the positive pressure in principle. Considering the exhaust time of the air, measures to shut off the air are still insufficient. Therefore, in the present embodiment, the purge block 40 is further provided outside the gate valve 18.
Has been arranged.

The purge box 46 of the purge block 40
For example, nitrogen gas is constantly supplied during operation of the system regardless of the opening / closing operation of the gate valve 18. Therefore, from the space 48 of the purge box 46,
The nitrogen gas is purged toward the passage 42 through the first to fourth slits 50 to 56. First to fourth
Stream of nitrogen gas ejected from the slit 50 to 56 of the, shown in F ₄ from F ₁ in FIG. 1. This nitrogen gas flow F
₁ F ₄ from each in the direction intersecting the carrying direction of the semiconductor wafer, thereby forming a multi-stage curtain with nitrogen gas. This multi-stage gas curtain can prevent the atmosphere from flowing into the vacuum side. In particular, the first to first
F ₃ from the gas curtain F ₁ which is formed from the third slit 50 to 54 is formed inclined to the outside atmosphere side as it goes from the upper end of the passage 42 downward. Therefore, the atmosphere flowing from the opening of the purge block 40 is:
Even once inside the opening, it will flow out of the opening of the purge block 40 according to the flow of the three-stage gas curtain. Further, the flow F ₄ of the nitrogen gas from the fourth slit 56 enhances the action of setting the atmosphere inside the passage 42 of the purge block 40 to a positive pressure than the atmospheric pressure. Thus, by forming a multistage gas curtain inside the purge block 40, the upper wall 42
Air to the inlet used along the c, since the gas ejection pressure near the upper wall 42c is high, so that flowing out the purge block 40 outside along the F ₃ from the gas curtain F _1.

On the inner surface of the two side walls 42a of the purge block 40, the flow rate of nitrogen gas is theoretically zero. Therefore, the air attempts to flow along the surface of the two side walls 42a. However, in the present embodiment, since the first to third guide plates 58 to 62 are formed to protrude inward from the two side walls 42a, 42a, such a flow of the atmosphere is physically blocked, and the gas flow is prevented. It will be flow out of the purge block 40 along the curtain F ₁ to F _3.

Next, the reason why the inclined surface 64 and the horizontal projecting surface 66 are provided near the outlet of the bottom wall 42b of the purge block 40 will be described. In the present embodiment, since the nitrogen gas is ejected from the slit provided on the upper wall 42c,
The nitrogen gas pressure on the b side becomes the lowest, and the atmosphere easily flows from this region. Furthermore, a swirl W1 as shown in FIG. ₁ is formed in a region where the flow of the nitrogen gas is weak.
If, if this vortex W ₁ is formed on the upper side of the bottom wall 42b, entrainment air currents will be formed inside the passageway 42 of the semiconductor wafer. In the present embodiment,
By forming the inclined surface 64 and a horizontal projecting surface 66, arranged such vortex W ₁ to the outside of the passage 42, thereby preventing entrainment of air. Further, in the vicinity of the outlet of the bottom wall 42b, a large number of the rectifying plate 68 in parallel at predetermined intervals along the width direction is provided, on the outside of the F ₃ from the gas curtain F ₁ at weak gas pressure region It realizes a smooth flow and prevents entrainment of the atmosphere.

Next, the reason why the corrugated plate 70 is provided on the upper surface of the bottom wall 42b in the region inside the current plate 68 will be described. Even on the bottom wall 42b, the flow rate of the nitrogen gas is theoretically zero. The first purpose of the corrugated plate 70 is to physically prevent the air from flowing into the inside along the bottom wall 42b. Further, the corrugated plate 70 traps the vortex W _{2 in} the region of the concave portion, and has a laminar flow state along the direction parallel to the line connecting the vertices of the corrugated plate 70 and outward from the inside of the purge block 40. forming a flow F _5. Such laminar flow by forming the flow F ₅ state so as to prevent the most gas pressure entrainment of air from the region near the weak bottom wall 42b. By the action as described above, the air flow conditions in the vicinity of the opening of the purge block 40, becomes as W ₃ shown in FIG. 1, inclusion of air into the purge block 40 inside is prevented.

By the way, in the vacuum apparatus according to the present invention, when forming the gas curtain, the ejection direction of the purge gas is set such that the direction of the purge gas is one of the directions intersecting with the direction of transport of the semiconductor wafer to be transported. Can also be set in a direction parallel to.

FIGS. 4, 5 and 8 show the configuration in this case.

That is, in FIG.
40 are left and right side walls 140a, as in the example shown in FIG.
The passage 142 of the semiconductor wafer W is defined by the lower wall 140a, the bottom wall 140b, and the upper wall 140c (not shown in FIG. 4) facing the bottom wall 140b. A purge box 146 that forms a space 148 between the side walls 140a and 140a of the purge block 140
a and 146b are fixed at positions facing each other across the passage 142 of the semiconductor wafer W, and one end of a branch pipe indicated by reference numeral 24 used in FIG. 1 is connected to one of the purge boxes 146a. Nitrogen gas is introduced inside. Further, one end of an exhaust pipe 150 connected to a vacuum device (not shown) is connected to the other purge box 146b so that exhaust from the inside is performed.

Further, slits 152a and 152b for communicating the purge boxes 146a and 146b with the passage 142 are formed in the side walls 140a and 140a. The slits 152a and 152b are
The longitudinal direction along the vertical direction of “a” is set, and the transport direction of the semiconductor wafer W (the direction indicated by the arrow in FIG. 4)
Are formed at intervals along the line. The direction in which the slits 152a and 152b penetrate the side wall 140a is set in a direction parallel to the surface of the semiconductor wafer W.

Of these slits, one of the slits 152a located on one purge box 146a side is formed as a jet port for jetting nitrogen gas from the space 148 of the purge box 146a toward the passage 142. The slit 152b located on the other purge box 146b side is formed as a suction port for sucking the nitrogen gas ejected into the passage 142.

Next, the operation will be described.

As shown in FIG. 5, the nitrogen gas ejected from the slit 152a located on one purge box 146a side cuts off the passage 142 parallel to the surface of the semiconductor wafer W and perpendicular to the carrying direction. After forming a multistage gas curtain by the laminar flow, the gas flows toward the slit 152b located on the other purge box 156b side and is sucked through the slit 152b. Therefore, even when the semiconductor wafer W passes, the flow of the nitrogen gas is hardly disturbed, so that the gas curtain is not disturbed.
As a result, the pressure fluctuation near the surface of the semiconductor wafer W is suppressed, and the diffusion of the atmosphere due to the pressure fluctuation can be almost completely prevented.

In the above embodiment, when the nitrogen gas is sucked, it is necessary to prevent the nitrogen gas from colliding with one inner surface of the side wall 140a and causing turbulence. It can be dealt with by setting the size of the opening of the slit 152b on the suction side or setting the suction force by the vacuum device. In addition, as described above, the slits forming the gas curtains of a plurality of stages along the transport direction are, for example, sequentially narrowed in the opening from the upstream side to the downstream side along the transport direction, so that the nitrogen gas is ejected. Speed can also be increased. In this case, the slit located at the most downstream side contributes to enhancing the action of setting the atmosphere in the passage 142 to a positive pressure than the atmospheric pressure.

On the other hand, in the embodiment shown in FIG. 4, the configuration is such that the purge gas ejection port and the suction port are combined, but only the ejection port is provided to form a gas curtain extending from the ejection port to the atmosphere side. Is also possible.

FIG. 6 shows an embodiment in this case.
In the vacuum apparatus according to the present embodiment, the purge box 146 having the same configuration as the embodiment shown in FIG.
140a. The first to fourth slits 160 to 166 penetrating in a direction parallel to the surface of the semiconductor wafer W are formed in the side wall 140 a on the side where the purge box 146 is fixed.
Are formed along the transport direction of Each slit 160
1 to 166, the space 148 of the purge box 146 communicates with the passage 142, and nitrogen gas for purging is ejected from the space 148 toward the passage 142, similarly to the embodiment shown in FIG. I have. The first to third slits are also inclined in the same manner as in the embodiment shown in FIG. 1, and the inclination angles θ1 to θ3 are determined with reference to a horizontal axis parallel to the surface of the semiconductor wafer W in FIG. Are set in the same angle and relationship as in the case shown in FIG. 7, and the fourth slit 166 is set in parallel with the horizontal axis.

The passage 142 of the purge block 140
Inside, as shown in FIG. 7, the bottom wall 140b and the top wall 1
First to third guide plates 170 to 174 projecting inward from the inner surface 40c by a predetermined length are fixed, and the guide plates 170 to 174 have slits similar to the embodiment shown in FIG. It is for guiding the nitrogen gas ejected from 160 to 164. And each guide plate 170 ~
One end in the extension direction of 174 is disposed at a position where it contacts the side wall 140a on the side where the purge box 146 is fixed, and the other end of the extension direction ends at a position where it does not reach the other side wall 140a.

On the other hand, an inclined portion 180 corresponding to the inclined surface in the embodiment shown in FIG. 1 is formed at the open end of the side wall 140a on the side where the purge box 146 is not fixed. An inclined surface is formed which is expanded laterally toward the tip, and the tip of the inclined surface is connected to a vertical projecting surface 180a which projects further to the outside atmosphere side than the opening of the purge block 140.

As shown in FIG. 7, the area formed by the inclined surface of the inclined portion 180 and the vertical protruding surface 180a has a predetermined interval in the vertical direction of the purge block 140, and A rectifying plate 190 that is arranged in parallel with the surface and whose end on the side of the passage 142 protrudes inward from the side wall 140b is provided. Further, on the downstream side of the rectifying plate 190 in the moving direction of the semiconductor wafer W, a corrugated plate 192 formed in a corrugated shape is disposed on the inner surface of the side wall 140b over the entire area in the vertical direction of the inner surface. The various members constituting the purge block 140 are made of, for example, stainless steel, as in the embodiment shown in FIG. 1, and the members are interconnected by, for example, spot welding.

Next, the operation will be described.

In the embodiment shown in FIG. 6, a state is obtained in which the flowing direction of the nitrogen gas in the embodiment shown in FIG. 1 is replaced with a direction parallel to the surface of the semiconductor wafer W. Therefore, the first to fourth slits 160 to 16
The nitrogen gas ejected from the nozzle 4 is denoted by reference characters F1 to F1 shown in FIG.
Describing using F2, a multi-stage curtain that flows along the surface of the semiconductor wafer W in a direction transverse to the carrying direction of the semiconductor wafer W is formed.

[0049] Even if the air that is going to flow in from the opening of the purge block 140 enters the inside through the opening, it flows out of the opening of the purge block 140 according to the flow of the three-stage gas curtain. Will be. In addition, the flow F4 of gas from the fourth slit 164
As in the case of the embodiment shown in FIG. 1, the action of setting the atmosphere in the passage 142 of the purge block 140 to a positive pressure rather than the atmospheric pressure is enhanced.

Further, the bottom wall 14 of the purge block 140
On the inner surface of the upper wall 140b and the upper wall 140c, the first to third guide plates 170 to 174 provide the same operation as the embodiment shown in FIG. The same effect as in the embodiment shown in FIG. 1 is obtained also behind the current plate 190, so that the air is prevented from being sprayed.

As described above, in the embodiment shown in FIG. 6, since the direction in which the purge gas flows is set in a direction parallel to the surface of the semiconductor wafer W, turbulent flow is generated in the gas curtain near the surface of the semiconductor wafer W. The pressure fluctuation in the vicinity of the surface due to the generation of the turbulent flow can be suppressed without causing the turbulence, and the air can be reliably prevented from being sprayed.

The purge gas used in the above-described embodiment is not limited to nitrogen gas.
It is preferable to use the same type as those used in each of these chambers so as not to adversely affect the processing in the load lock chamber and the process chamber. For example, in addition to nitrogen gas, CO2 or a purified dry gas may be used. Can be used.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention. For example, if the apparatus of the present invention is formed as the purge block 40 as in the above embodiment, there is an effect that connection to an existing vacuum apparatus can be achieved by providing a connection shape such as a flange. However, the present invention is not limited to this, and the same function as the purge block 40 may be integrally provided, for example, as the shape on the gate valve outlet side. Further, the present invention is not limited to the vacuum apparatus in which the process chamber 10 and the load lock chambers 12 and 14 are connected as in the above-described embodiment, but is also applicable to an apparatus which is connected to a single vacuum chamber integrally or separately. Be adaptable.

Further, according to the present invention, since the direction of the purge gas ejection port is set in a direction parallel to the surface of the semiconductor wafer, it is possible to prevent turbulence near the surface of the semiconductor wafer. Therefore, the pressure fluctuation on the surface of the semiconductor wafer is suppressed to prevent the air from being scattered, and the inflow of the air is more reliably prevented, so that the evacuation time can be reduced.

[0055]

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view for explaining an embodiment in which the present invention is applied to a structure on an atmosphere opening side of a decompression processing system.

FIG. 2 is a front view of the purge block shown in FIG. 1 as viewed from an opening side.

FIG. 3 is a schematic explanatory diagram for explaining an overall configuration of a decompression processing system to which the present invention is applied.

FIG. 4 is a schematic cross-sectional view for explaining another embodiment in which the present invention is applied to the structure on the atmospheric opening side of the decompression processing system.

FIG. 5 is a front view of the purge block shown in FIG. 4 as viewed from an opening side.

FIG. 6 is a schematic cross-sectional view for explaining still another embodiment in which the present invention is applied to the structure on the atmosphere opening side of the decompression processing system.

FIG. 7 is a front view of the purge block shown in FIG. 6 as viewed from an opening side.

FIG. 8 is a perspective view of the purge block shown in FIGS.

[Explanation of symbols]

 40, 140 Purge block 42, 142 Passage 46, 146 Purge box 50-56 Slit 58-62 Guide plate 68 Rectifier plate 70 Corrugated plate 152a, 152b Slit W Semiconductor wafer

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-224133 (JP, A) JP-A-3-175622 (JP, A) JP-A-63-239938 (JP, A) JP-A-2- 45920 (JP, A) JP 39-20989 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/3065 H01L 21/205 H01L 21/31

Claims (5)

(57) [Claims] 1. A vacuum device having an exhaust means, a gas supply means, and an opening / closing port provided between the atmosphere and a load / unload object between a space capable of reducing pressure and the atmosphere. the off opening is arranged on the atmosphere side than the passage of the closure to the subsequently formed the object to be transferred, provided along the conveying direction of the object to be transferred before Symbol passage, path
A plurality of <br/> spout to form a gas curtain in a plurality of stages, a plurality of ejection ports and respectively open end by Jigasu, said gas supply
Means for directing the purge gas to each of the jet ports
A plurality of slits, and a passage of the passage at a position opposed to each of the plurality of ejection ports.
It is arranged to protrude from the inner wall, and
Guide the purge gas ejected to the atmosphere side
Includes a guide plate for the each of the plurality of slits, the vertical surface of the passageway to
Has an inclination angle θ (θ> 0) inclined toward the atmosphere side.
And the inclination angle of the slit farther from the atmosphere side
Is larger than the inclination angle of the slit close to the atmosphere side . 2. A vacuum device having an exhaust means, a gas supply means, and an opening / closing port provided between the atmosphere and a load / unload object between a space capable of reducing pressure and the atmosphere. the off opening is arranged on the atmosphere side than the passage of the closure to the subsequently formed the object to be transferred, provided along the conveying direction of the object to be transferred before Symbol passage, path
A plurality of <br/> spout to form a gas curtain in a plurality of stages, a plurality of ejection ports and respectively open end by Jigasu, said gas supply
Means for directing the purge gas to each of the jet ports
It has a plurality of slits inside, a scan of the farthest from the air side of the plurality of slits
The lit is a vertical slit parallel to the vertical plane of the passage.
Ri, each of the other slit except for the vertical slit of the plurality of slits, to the atmosphere side with respect to the vertical plane of the passageway
Having an inclination angle θ (θ> 0) inclined toward the atmosphere side
The inclination angle of the slit at a farther position is closer to the atmosphere side.
A vacuum device characterized by being larger than a close inclination angle of the slit . 3. An inner peripheral wall according to claim 1, wherein said plurality of ejection ports are formed in said passage.
Opposing inner peripheral wall surfaces, which intersect with the gas curtain.
Formed in the area to be inserted and formed of the gas curtain
Incline to allow the formation of the gas curtain
Part, formed so as to extend from the end of the inclined portion on the atmosphere side,
The passage projects toward the atmosphere from the open end of the passage on the atmosphere side.
A vacuum device , comprising: a protrusion . 4. The gas car according to claim 1 , wherein the gas passage is an open end of the passage on the atmosphere side.
In the position where the gas pressure on the downstream side of the ten
Rectifiers arranged in parallel at intervals along the width direction
A vacuum device comprising a plate . 5. The corrugated plate according to claim 4, wherein a corrugated plate is provided in a region inside the passage than the plurality of current plates.
Providing a vortex in the recess of the corrugated plate;
Along the direction parallel to the line connecting the vertices of the
A vacuum device for forming a laminar flow from inside toward the atmosphere .