JP2008223538A - Cryo pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cryo pump capable of preventing a drop in exhaust capability and cooling capability during operation of the cryo pump when a large amount of water is exhausted, thereby enabling shortening of regeneration time and long-term use of the cryo pump. <P>SOLUTION: The cryo pump includes a cryo pump container 14, a refrigerator 15, a radiation shield 18 provided within the cryo pump container and connected to a cooling stage of the refrigerator, and a louver 20 arranged at an opening portion of the radiation shield 18. A water storage section 32 for exhausting the water to the exterior of the cryo pump container 14 is arranged outside of the radiation shield 18. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cryopump, and more particularly to a cryopump that is used for evacuating a vacuum processing apparatus and is suitable for performing a regeneration operation after exhausting a large amount of water in a short time.

  The cryopump is a vacuum exhaust pump that collects gas molecules to be exhausted by condensing and adsorbing them at an extremely low temperature. Therefore, if used for a certain period of time, the exhaust performance decreases. For this reason, the cryopump periodically performs regeneration work. In this regeneration operation, the temperature of a low-temperature part such as a cooling stage or a cooling panel connected to the refrigerator is raised to room temperature or a gas vaporization temperature, and the stored gas is vaporized and discharged.

  When a large amount of water is exhausted by the cryopump, a large amount of ice is condensed and generated especially in the louver. When the ice condensed in the louver is melted and discharged as water during the regenerating operation, water falls and accumulates in the radiation shield inside the cryopump container in the conventional cryopump. The water further wets the activated carbon of the activated carbon panel for exhausting hydrogen gas, helium gas, etc. in the radiation shield, or enters the gap below the cooler from the joint between the radiation shield and the first stage. . For this reason, it took a lot of time to discharge this water in the subsequent roughing.

  As conventional techniques for solving the above problems, there are those disclosed in Patent Documents 1 to 3.

  In the cryopump according to Patent Document 1, water melted at the time of regeneration is accumulated inside the radiation shield, but a fixed portion where water accumulates is formed at the bottom of the radiation shield, and a drain hole and a drain valve structure are formed at the location. Is provided. With this configuration, even if the louver ice melts and accumulates in the radiation shield during regeneration, it will accumulate in the drain hole part to reduce the effect on other parts and open the drain valve appropriately. It is discharged outside through the drain hole.

  In the cryopump according to Patent Document 2, a drain hole is formed at the bottom of the portion corresponding to the radiation shield, and water accumulated in the portion corresponding to the radiation shield is discharged downward through the drain hole, and the lower side of the portion corresponding to the radiation shield In addition, a water receiving member, piping, valves and the like for discharging water are provided outside the cryopump container.

In the cryopump according to Patent Document 3, the louver (cold baffle) is provided with a structure for guiding water when the ice condensed on the louver melts, a drain hole is formed, and further inside the radiation shield (reflector) A water receiver is provided at a location near the louver below the louver so as to receive the cryopump container without dropping it. The water from the louver is collected in the water tray. The water receiver includes a drainage basin formed so as to pass through the inside of the radiation shield, and the water collected in the water basin is guided to the outside of the radiation shield through the drainage basin and further discharged to the outside of the cryopon container. Further, a heater for heating the radiation shield is provided so that the ice condensed and adsorbed on the louver can be quickly melted. The louver has a V-shaped lower end portion so as to function as a gutter, and the drainage hole is formed at the lower end of the V-shaped portion.
Japanese Utility Model Publication No. 3-43430 Japanese Utility Model Publication No.59-81784 JP-A-62-3177

  The above conventional techniques have the following problems. The cryopump according to Patent Document 1 or Patent Document 2 has a structure in which water is received and collected at the bottom of the radiation shield, so that the inside of the radiation shield is wetted extensively, and the activated carbon and the condensation panel of the activated carbon panel are wetted. And the problem of water remaining in fine gaps could not be solved sufficiently. As a result, it still took a long time to remove the water by roughing.

  Further, according to the cryopump according to Patent Document 3, the water received by the water receiver below the louver is discharged through the water discharge pipe formed inside the radiation shield, so that the exhaust function of the pump is lowered. Furthermore, since the water discharge pipe does not have a structure that is actively cooled, the cryogenic cooling panel at the center of the cryopump is warmed by the radiant heat generated from the cryopump when it operates, reducing the cooling efficiency. The problem of making it also arises.

  The object of the present invention is to consider the above-mentioned problem of the cryopump disclosed in Patent Document 3 in particular, and when evacuating a large amount of water with the cryopump, the ice condensed in the louver becomes water during the regeneration operation. It is intended to shorten the regeneration time of the cryopump without reducing the exhaust capacity and cooling capacity during operation of the cryopump by reducing the amount of gas entering the radiation shield when discharged. .

  The object of the present invention, in view of the above-mentioned problems, can prevent a reduction in exhaust capacity and cooling capacity during operation of the cryopump when exhausting a large amount of water, shorten the cryopump regeneration time, It is to provide a cryopump that can be used for a long time.

  The cryopump according to the present invention is configured as follows to achieve the above object.

  The first cryopump (corresponding to claim 1) includes a cryopump container, a refrigerator, a radiation shield provided inside the cryopump container and connected to a cooling stage of the refrigerator, and an opening of the radiation shield The cryopump provided with the louver is provided with a water storage unit that discharges water to the outside of the cryopump container outside the radiation shield.

  In the above cryopump, when a large amount of water is exhausted, when the ice condensed and adsorbed on the louver is melted and discharged as water during the regeneration operation, the water that is discharged from the louver at the water guide section is discharged outside the cryopump container. To the water storage section provided in Accordingly, water can be efficiently discharged even during regeneration of a cryopump that exhausts a large amount of water, and regeneration can be performed in a short time and satisfactorily.

  In the above configuration, the second cryopump (corresponding to claim 2) is preferably characterized by including a water guide portion that guides water condensed in the louver to the water storage portion.

  In the above configuration, the third cryopump (corresponding to claim 3) is preferably configured such that the water guide portion is formed such that the lower surface of the louver is inclined downward toward the upper position of the water storage portion. Characterized.

  In the above cryopump, when a large amount of water is exhausted, the water guide part guides the water coming out of the louver by the water guide part, and it is provided around the opening of the cryopump container without passing through the inside of the radiation shield. Led to the reservoir. Thus, it is possible to prevent water from entering the radiation shield or the cryopump container.

  The fourth cryopump (corresponding to claim 4) is preferably characterized in that, in the above configuration, the water guide portion is a water receiving water channel member provided below the louver.

  In the above configuration, the fifth cryopump (corresponding to claim 5) is preferably configured so that the pioneer guide portion has an aggregating plate having a folded shape in which the louver guides water, and the surface of the aggregating plate Characterized by the formation of grooves or ridges.

  In the above configuration, the sixth cryopump (corresponding to claim 6) is preferably characterized in that the water storage part is provided with a water discharge part for guiding water to the outside of the cryopump container.

  A seventh cryopump (corresponding to claim 7) is characterized in that, in each of the above-mentioned configurations, the water storage portion is preferably provided in a ring shape so as to surround the periphery of the radiation shield. With this configuration, since water discharged directly to the outside of the cryopump container is directly taken out, it is possible to prevent water from entering the inside of the radiation shield or the like.

  The eighth cryopump (corresponding to claim 8) is preferably characterized in that, in each of the above-described configurations, a heating mechanism is provided in the water storage section.

  A ninth cryopump (corresponding to claim 9) is preferably characterized in that, in each of the above configurations, the louver is cooled by a second refrigerator. By cooling only the louver with another single-stage second refrigerator unit, for example, even when exhausting a large amount of water, it can be used for a long time.

  According to the present invention, when a cryopump that exhausts a large amount of water is regenerated, the ice condensed on the condenser plate of the louver is melted and discharged to the outside as water, and dropped into the radiation shield or the cryopump container. Or without using a space inside the radiation shield, it is possible to discharge directly to the outside of the radiation shield or the cryopump container, thus shortening the regeneration work without reducing the cooling efficiency. Can be done in time and well. In addition, since water does not penetrate into the activated carbon or enter the gaps between the internal parts of the cryopump, there is an effect that poor regeneration and cracking / peeling of the activated carbon hardly occur. Furthermore, since the inside and outside of the radiation shield are not connected by a structure and heat is not transmitted by heat conduction, there is an effect that the cooling efficiency is not lowered.

  In addition, according to the present invention, since the water storage part that receives the water discharged from the louver is provided outside the radiation shield, there is no influence of thermal radiation from the water storage part, and the exhaust efficiency and cooling efficiency during the cryopump operation are reduced. It has the effect of not letting it happen.

  According to the present invention, since the heating mechanism (heater or the like) is provided in the water storage section, it is possible to easily warm up and shorten the regeneration time.

  According to the present invention, since the water reservoir is formed at the outer peripheral edge of the opening of the cryopump container, the diameter of the louver can be increased and the exhaust efficiency can be increased.

  Further, according to the present invention, the louver is supported by the second refrigerator and cooled by this, so that the water from the louver can be reduced from entering the radiation shield, and the refrigerating capacity can be increased. Even if water is exhausted, it can be used for a long time.

  DESCRIPTION OF EMBODIMENTS Preferred embodiments (examples) of the present invention will be described below with reference to the accompanying drawings.

  1 and 2 show a first embodiment of a cryopump according to the present invention. First, a general configuration of a cryopump will be described with reference to FIG. The cryopump 11 is a vertical cryopump. The cryopump 11 is attached to the vacuum processing device 13 via an inlet valve 12. The cryopump 11 carries out various gases existing inside the vacuum processing apparatus 13 to the outside and evacuates the vacuum processing apparatus 13.

  The cryopump 11 includes a cryopump container 14, and a refrigerator 15 is attached to the lower part of the cryopump container 14. The refrigerator 15 includes a first stage 16 and a second stage 17 that extend inside the cryopump container 13. In the refrigerator 15, the first stage 16 is cooled to, for example, 50 to 150K, and the second stage 17 is cooled to, for example, 20K or less. A radiation shield 18 is attached to the first stage 16 in a state where thermal contact is good.

  The radiation shield 18 has a bowl shape, and is disposed inside the cryopump container 14 with the upper portion as an opening 18a. The opening 18a of the radiation shield 18 and the opening 14a of the cryopump container 14 are located at substantially the same position.

  A louver 20 is attached to the radiation shield 18 arranged inside the container of the cryopump 11 in the same manner in a good thermal contact with the opening 18a on the inlet 19 side. A cryopanel (cooling panel or condensing panel) 21 is attached to the second stage 17 in a good thermal contact state, and activated carbon 22 is bonded onto the cryopanel 21.

  The intake port 19 is connected to the vacuum processing device 13 via the intake port valve 12. From the vacuum processing device 13, water, carbon dioxide, argon, nitrogen, etc., hydrogen, neon, and helium enter the cryopump container 14 through the intake valve 12. Water and carbon dioxide are condensed and adsorbed on the louver 20 and the radiation shield 18 in the cryopump 11. Argon, nitrogen, and the like collide with the louver 20 and the radiation shield 18 and are cooled in advance, and then reach the cryopanel 21 where they are condensed. Hydrogen, neon, and helium collide with the louver 20 and the radiation shield 18 and cool in advance, then collide with the cryopanel 21 and further cool, and then reach the activated carbon 22 on the cryopanel 21 to be adsorbed and exhausted.

  Since the cryopump 11 is a storage type pump, the first stage 16 and the second stage 17 in the cryogenic state of the refrigerator 15 are regularly cooled to room temperature or a vaporization temperature corresponding to the type of the stored gas. The temperature is raised and the stored gas is vaporized and discharged. This operation is usually called “regeneration”.

  When performing the regeneration operation, an inert gas such as nitrogen is usually introduced into the cryopump container 14 through the purge valve 23 as a purge gas. This is because the purge gas is applied as a heat load to perform regeneration faster. Further, purging may be performed in order to dilute the accumulated gas and discharge it from the release valve 24. Furthermore, along with purging with nitrogen or the like, each stage may be heated and regenerated by heating each stage with a heater.

  When a large amount of water is exhausted by the cryopump 11, the ice condensed on the condensing plate of the louver 20 is melted during the regeneration operation, and a large amount of water is discharged from the louver 20. A structural part related to water discharge when a large amount of water is discharged will be described with reference to FIG. FIG. 2 is a longitudinal sectional view showing the cryopump container 14, the radiation shield 18, and the louver 20 in an enlarged and more accurate and detailed manner.

  In FIG. 2, the inlet flange 31 of the cryopump container 14 in the cryopump 11 is preferably larger in diameter than the conventional size, and is provided with a ring-shaped water reservoir 32 around the outside of the opening 14 a. The upper side of the water reservoir 32 is open. As shown in FIG. 2, the bottom surface of the water storage section 32 is inclined from the left side to the right side as an example, and a drain port 33 and a drain valve 34 are provided at the lowest position. The drain valve 34 is controlled to open and close at an appropriate timing, and the water 35 accumulated in the water storage section 32 is discharged to the outside. The louver 20 provided in the opening 18 a of the radiation shield 18 is made so that its diameter is large, and its peripheral edge faces the upper side of the ring-shaped water storage part 32. That is, in the louver 20, preferably, each of the plurality of condensing plates is formed so that the lower part or the lower edge is inclined in the longitudinal direction. Since the louver 20 is formed in such an inclined shape, when water is generated during the regenerating work, the water is guided and moved along the plurality of condensing plates by the inclined shape, and enters the water storage section 32. The structure is easy to flow.

  The louver 20 is not formed in an inclined shape, but a conventional normal louver may be arranged so as to be inclined so that a similar inclined state is created.

  The louver 20 usually has a plurality of condensing plates arranged in a parallel positional relationship, but all the condensing plates are arranged in an inclined shape or posture as described above.

  The louver 20 is supported by the radiation shield 20 by a copper material 36 having good thermal conductivity at the opening 18 a of the radiation shield 18. Since the other configuration of the cryopump 11 is the same as the configuration described in FIG. 1, the same elements are denoted by the same reference numerals and the description thereof is omitted.

  As shown in FIG. 2, in the water storage section 32 having an inclined bottom surface, for example, a heater (heating mechanism) 37 is provided at a location near the bottom surface.

  According to the cryopump 11 having the above-described configuration, when ice is melted and water is generated during the regeneration operation, the water is guided to the inclined shape (water guide portion) and guided into the water storage portion 32, It collects in the water storage part 32. Water hardly enters the radiation shield 18 or falls. In addition, when roughing is performed in a state where there is water inside the cryopump 11, there is a possibility that the water becomes ice due to the loss of vaporization heat and cannot be discharged. However, as described above, there is a heater 37 around the water storage unit 32. This can be prevented by heating the water storage section 32 by providing the above.

  Next, a second embodiment of the cryopump according to the present invention will be described with reference to FIGS. 3 is a view similar to FIG. 2, FIG. 4 is a plan view of the louver 20, and FIG. 5 is a cross-sectional view taken along line AA in FIG. 3 to 5, elements that are substantially the same as those described in the first embodiment are given the same reference numerals, and descriptions thereof are omitted.

  In the second embodiment, a plurality of water receiving channel members 41 inclined along the inclined shape are provided on the lower side of the louver 20. The plurality of water receiving water channel members 41 are preferably disposed on the lower side along the lower edges of the plurality of condensing plates 20a as shown in FIG. A drain hole 41 a is formed at a position corresponding to the position of the water storage portion 32 of the water receiving channel member 41. In the louver 20, the plurality of condensing plates 20 a are inherently inclined in the width direction. Therefore, when the ice adsorbed on each condensing plate 20 a melts, the ice in the width direction moves downward and in the longitudinal direction. Move in the tilt direction. Finally, the water that reaches the lower edge flows into the water receiving water channel member 41 and is further guided to the water storage section 32. The water receiving water channel member 41 is supported by a support portion 42 provided on the inner wall surface of the water storage portion 32 on the cryopump container 13 side. Other configurations are substantially the same as those described in the first embodiment.

  According to the configuration of the second embodiment described above, the water that exits the louver 20 during the regeneration is reliably guided to the water storage section 32 and reliably prevented from entering the cryopump container 14 or the radiation shield 18. Can do. Further, since the water receiving water channel member 41 should not condense water when the cryopump is exhausted, the water receiving channel member 41 is supported by the cryopump container 14 side and used in a normal temperature state.

  Next, a third embodiment of the cryopump according to the present invention will be described with reference to FIG. FIG. 6 is a view similar to FIG. In FIG. 6, elements that are substantially the same as those described in the first embodiment or the second embodiment are denoted by the same reference numerals, and description thereof is omitted.

  In this 3rd Embodiment, with respect to the louver 20, the separate other refrigerator 51 for attaching the louver 20 to cryogenic temperature and maintaining the performance of a cryopump is attached. The refrigerator 51 is preferably a one-stage refrigerator unit. The refrigerator 51 is supported and fixed on the cryopump container 14 side. In this embodiment, the louver 20 is supported while being connected to the refrigerator 51. Other configurations are basically the same as those of the second embodiment.

  According to the configuration of the third embodiment described above, when a large amount of water is exhausted by the cryopump 11, the louver 20 can be held at a very low temperature by the other refrigerator 51, and thereby the exhaust of the cryopump 11. Performance can be increased.

  Next, various embodiments of the above-described louver 20 will be described. The louver according to the first and second examples shown in FIGS. 7 to 12 is an example of a louver provided with a member on the lower side that is the same as or similar to the water receiving channel member (41) described in the second embodiment. Is shown. FIGS. 13-20 shows the example of the louver which does not have a water receiving water channel member.

  7 to 9 show a louver 20A according to the first embodiment. 7 is a plan view of the louver 20A, FIG. 8 is a sectional view taken along line BB in FIG. 7, and FIG. 9 is a sectional view taken along line CC in FIG.

  In this louver 20 </ b> A, one water receiving channel member 61 is provided on the lower side thereof at a position corresponding to the diameter position that is the lowest point in the inclination direction of each condensing plate 62. Each of the plurality of condensing plates 62 provided in the louver 20A is arranged in a positional relationship orthogonal to the water receiving channel member 61 as shown in FIG. Further, as shown in FIGS. 7 and 8, the plurality of condensing plates 63 are divided into left and right groups with the water receiving water channel member 61 as the center line position. In each of the left and right groups, the plurality of condensing plates 62 are arranged in the longitudinal direction of the water receiving water channel member 61, and each of the plurality of condensing plates 62 is arranged to be inclined toward the water receiving water channel member 61. . Further, each of the plurality of condensing plates 62 is inclined in the width direction so that the upper interval is narrowed as shown in FIG. 9, and is inclined in the longitudinal direction toward the water receiving channel member 61. According to the louver 20A described above, a large amount of water can be efficiently collected using one water receiving channel member 61 and guided to the water storage unit 63 disposed on the lower side of the one end side.

  Next, FIGS. 10 to 12 show a louver 20B according to the second embodiment. 10 is a plan view of the louver 20B, FIG. 11 is a sectional view taken along line DD in FIG. 10, and FIG. 12 is a sectional view taken along line EE in FIG.

  In this louver 20 </ b> B, one water receiving channel member 71 is provided on the lower side of the louver 20 </ b> B at a location corresponding to the diameter position that is the lowest point in the inclination direction of each condenser plate 72. Each of the plurality of condensing plates 72 provided in the louver 20B has a concentric positional relationship as shown in FIG. 10, and is divided into left and right groups with the water receiving water channel member 71 as the center line position, and in a semicircular shape. Are lined up. Further, each of the plurality of condensing plates 72 has an inclined portion in the width direction and is inclined toward the water receiving water channel member 71. According to the louver 20B described above, a large amount of water can be efficiently collected using one water receiving channel member 71 and further guided to the water storage portion 73 provided on the lower side of one end thereof.

  Next, FIGS. 13 to 15 show a louver 20C according to the third embodiment. 13 is a plan view of the louver 20C, FIG. 14 is a sectional view taken along line FF in FIG. 13, and FIG. 15 is a sectional view taken along line GG in FIG.

  In this louver 20C, each of the plurality of plate-shaped condensing plates 81 has an inner center so as to guide water to a ring-shaped water storage portion 32 provided around the outside of the opening of the cryopump container 14. It is arranged so that the part side is raised and the outside is lowered. Each of the plurality of condensing plates 81 is inclined in the width direction so that the upper interval is narrowed, and is inclined in the longitudinal direction toward the outer water storage portion 32. In addition, as shown in FIG. 16, it is desirable that a plurality of linear streak-like grooves 82 are provided in the longitudinal direction on the upper surface of the condensing plate 81 so as to guide water. According to the louver 20C described above, a large amount of water can be efficiently collected and guided to the water storage section 32 without using a water receiving channel member. The groove 82 can be provided in the condenser plate of the louver in each of the embodiments described above.

  Next, FIGS. 17 to 19 show a louver 20D according to the fourth embodiment. 17 is a plan view of the louver 20D, FIG. 18 is a perspective view, and FIG. 19 is a cross-sectional view taken along line HH in FIG. In the perspective view of FIG. 18, some of the plurality of condenser plates are omitted.

  The louver 20D includes a central inner cylinder 91 and an outer cylinder 92 that are concentrically positioned, and a plurality of condensing plates 93 that are provided radially at equal intervals are disposed between these cylindrical members. Each condensing plate 93 has a narrow end 93a on the center side and a wide end 93b on the outer peripheral edge, and further inclines in the width direction and the lower side 93c extends from the center to the outer peripheral edge. It is inclined to become lower as it goes to. Further, as shown in FIG. 17, a plurality of the grooves 82 are provided on the upper surface of each condenser plate 93. In FIG. 18 and the like, the illustration of the groove 82 is omitted. According to the louver 20D described above, a large amount of water can be efficiently collected and guided to the ring-shaped water reservoir 32 without using a water receiving channel member.

  FIG. 20 shows a modification of the condensing plate 93 in the louver 20D. The condensing plate 93-1 has a folded portion 94 on the lower side. The folded portion 94 can prevent water from falling downward and guides the water to the outer peripheral edge. Since the outer end 93b of the condensing plate 93-1 is in contact with the outer cylinder 92, a hole 95 is formed so that water is dropped into the water reservoir 32 at the outer end. Instead of the hole 95, a notch for dropping water downward may be formed.

  The configurations, shapes, sizes, and arrangement relationships described in the above embodiments are merely shown to the extent that the present invention can be understood and implemented, and the numerical values and the compositions (materials) of the respective configurations are as follows. It is only an example. Therefore, the present invention is not limited to the described embodiments, and can be variously modified without departing from the scope of the technical idea shown in the claims.

  The cryopump of the present invention is used to evacuate a vacuum processing apparatus and is used particularly when a large amount of water is exhausted.

It is a longitudinal section showing a 1st embodiment of a cryopump concerning the present invention. It is an enlarged vertical sectional view of the cryopump according to the first embodiment. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the cryopump which concerns on this invention. It is a top view of the louver in the cryopump which concerns on 2nd Embodiment. It is the sectional view on the AA line in FIG. It is a longitudinal cross-sectional view which shows 3rd Embodiment of the cryopump which concerns on this invention. It is a top view which shows 1st Example of a louver. It is the BB sectional view taken on the line in FIG. It is CC sectional view taken on the line in FIG. It is a top view which shows 2nd Example of a louver. It is the DD sectional view taken on the line in FIG. It is the EE sectional view taken on the line in FIG. It is a top view which shows 3rd Example of a louver. It is the FF sectional view taken on the line in FIG. It is the GG sectional view taken on the line in FIG. It is a fragmentary figure which shows the surface of the condensing plate of the louver which concerns on 3rd Example. It is a top view which shows 4th Example of a louver. It is a perspective view of the louver which concerns on 4th Example. It is the HH sectional view taken on the line in FIG. It is a perspective view which shows the modification of the condensing plate used with the louver which concerns on 4th Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Cryopump 14 Cryopump container 15 Refrigerator 18 Radiation shield 20 Louver 32 Water storage part 33 Drain outlet 34 Drain valve 37 Heater 41 Water receiving channel member 51 Refrigerator

Claims (9)

In a cryopump comprising a cryopump container, a refrigerator, a radiation shield provided inside the cryopump container and connected to a cooling stage of the refrigerator, and a louver provided at an opening of the radiation shield,
A cryopump characterized by comprising a water storage part for discharging water to the outside of the cryopump container outside the radiation shield.   The cryopump according to claim 1, further comprising a water guide portion that guides water condensed in the louver to the water storage portion.   The cryopump according to claim 2, wherein the water guide portion is formed by a lower surface of the louver being inclined downward toward an upper position of the water storage portion.   The cryopump according to claim 2, wherein the water guide portion is a water receiving water channel member provided below the louver.   3. The cryopump according to claim 2, wherein the pioneer guide portion has an aggregating plate having a folded shape in which the louver guides water, and grooves or ridges are formed on a surface of the aggregating plate.   The cryopump according to any one of claims 1 to 5, wherein a water discharge part that guides the water to the outside of the cryopump container is provided in the water storage part.   The cryopump according to claim 1, wherein the water storage section is provided in a ring shape so as to surround the periphery of the radiation shield.   The cryopump according to claim 1, wherein a heating mechanism is provided in the water storage section.   The cryopump according to any one of claims 1 to 8, wherein the louver is cooled by a second refrigerator.

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