JPH11294330A - Cold trap and vacuum exhaust device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To regenerate a cold trap without stopping a refrigerator and safely. SOLUTION: Piping 8 is wound at the heat station 7 of a cold trap 1. To the piping 8, a nitrogen cylinder 11 is connected by a passage 10 providing a motor-operated valve 9. A controller 13 delivers a control signal to a valve driver 15 so as to release the motor-operated valve 9, when the regenerating cycle passes. By heating a panel 6 and carrying out the regeneration process without stopping the operation of the refrigerator 3, the cooldown time is reduced and the operation rate is improved. By setting no electric heater in an enclosure 4, a short-circuit, a power leakage, and a danger of explosion are eliminated, so as to realize a low cost by using no heater.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cold trap capable of safely regenerating a refrigerator without stopping the refrigerator, and a vacuum exhaust apparatus using the cold trap and a turbo molecular pump in combination.

[0002]

2. Description of the Related Art Conventionally, there is a cryopump as a device for evacuating a vacuum chamber of a semiconductor manufacturing apparatus or the like. Since this cryopump is a so-called built-in type in which gas molecules are adsorbed on a cooled heat panel, it is necessary to perform a regeneration operation at regular operation times. However, the cycle time of the regeneration operation is as short as about one week, and the operation rate is poor. Therefore, when a high operation rate is required, a turbo-molecular pump is used which compresses and exhausts gas molecules at a high compression ratio by a moving blade rotating between the stationary blades at a high speed.

The above-mentioned turbo molecular pump can be operated continuously for about one year. However, due to its function, gas molecules having a small molecular weight have a reduced exhaust performance. In particular, it is difficult to evacuate a large amount of water vapor existing in the atmosphere, and the evacuating performance of the water vapor is extremely low, which is 1/3 to 1/5 of that of a cryopump. Therefore, there has been proposed an evacuation apparatus in which a cold trap having a panel (heat exchange section) for freezing and collecting water molecules having a small molecular weight cooled by a helium refrigerator is connected to an intake port of a turbo molecular pump (particularly). Fairness 8-253879
No. 6). Then, in the turbo molecular pump, water vapor having low exhaust performance is accumulated in a cold trap panel and removed.

[0004] In this way, the cold trap panel in which the water vapor is frozen and collected closes the gate valve between the cold trap and the vacuum chamber, and (1) stops the cold trap.
(That is, the helium refrigerator is stopped) or (2) the panel is regenerated by heating the panel with a heater.

[0005]

However, the above-mentioned conventional evacuation apparatus has the following problems. That is, the regeneration cycle of the cold trap is approximately one month. Therefore, in the case of (1), there is a problem that the operation rate of the entire evacuation apparatus is limited by the cold trap despite the fact that a turbo molecular pump capable of continuous operation for about one year is used. is there. In the case of (2), by discharging steam while the helium refrigerator is operating, the cool-down time can be shortened and the function stop period of the cold trap can be shortened. However, providing a heater on the panel has the following problems.

That is, there is a risk of electric leakage or short circuit due to deterioration of the insulation resistance of the heater. The heater used in the cold trap is 100 ° C.
The filament and the resistance element at 700 ° C. are sheathed so that the exhaust gas does not directly come into contact with the filament. However, if this sheath is broken, there is a danger that hydrogen gas will directly touch the filament or the resistance element and explode. In addition, since the heater is a consumable item, it needs to be replaced in one to two years, which increases running costs. Further, it is necessary to separately provide a power supply for the heater, which increases the cost.

Therefore, an object of the present invention is to provide a cold trap that can safely regenerate a refrigerator without stopping the refrigerator.
Another object of the present invention is to provide a vacuum evacuation device using both the cold trap and the turbo molecular pump.

[0008]

According to one aspect of the present invention, there is provided a cold trap for freezing and collecting gas molecules on a panel attached to a heat station section of a refrigerator. A heat medium pipe for flowing a heat medium is brought into contact with at least one of the panel and the panel.

According to the above configuration, when the heat medium is supplied to the heat medium pipe which is in contact with at least one of the heat station section and the panel, the panel is heated or cooled by the heat or cold of the heat medium. You. Thus, heating and cooling of the panel are performed without stopping the refrigerator.

The invention according to claim 2 is a cold trap according to claim 1, wherein the heat medium is:
It is a heating medium for heating at least one of the heat station section and the panel.

According to the above configuration, when the heating medium for heating is supplied to the heating medium pipe and the panel is supplied with heat that exceeds the refrigerating capacity of the refrigerator, the temperature of the panel is frozen and collected. Regeneration is performed when the temperature reaches a temperature at which certain gas molecules are vaporized. Thus, the regeneration process is performed without stopping the refrigerator.

According to a third aspect of the present invention, in the cold trap according to the first aspect, the heat medium includes:
A cooling heat medium for cooling at least one of the heat station section and the panel.

According to the above configuration, when the cooling medium is supplied to the heating medium pipe, the panel is supplied with an amount of cold heat equal to or higher than the refrigerating capacity of the refrigerator. In this way, it is possible to shorten the cool-down time and improve the vacuum pumping capacity under a high heat load.

According to a fourth aspect of the present invention, in the cold trap according to the second or third aspect, the heat medium pipe projects outside the cold trap, and the protrusion of the heat medium pipe protrudes. A motor-operated valve interposed in the sensor, a temperature sensor that detects the temperature of the panel and outputs a signal representing the detected temperature, and receives a signal from the temperature sensor so that the temperature of the panel becomes a predetermined temperature. A controller for controlling the opening of the electric valve is provided.

According to the above configuration, if the target temperature of the panel controlled by the controller is set to a temperature at which the gas molecules frozen and collected are vaporized, the panel temperature is controlled by the controller. The opening of the electric valve of the heat medium pipe is controlled so that the temperature becomes equal to the temperature. Thus, by supplying the heating medium for heating to the heating medium pipe, the regeneration processing is automatically performed without stopping the refrigerator.

According to a fifth aspect of the present invention, in the cold trap according to the fourth aspect of the present invention, the cold trap includes a heater provided at the projecting portion of the heat medium pipe through which the heat medium for heating flows. The on / off of the heater can be controlled according to the temperature of the panel.

According to the above configuration, the heater is turned on by the controller at the start of the regeneration process, and the panel is heated to the vaporization temperature of the gas molecules frozen and collected in the panel in a short time.

According to a sixth aspect of the present invention, there is provided the cold trap operating method according to the fourth aspect of the present invention, wherein the temperature of the panel is set such that gas molecules other than water vapor are frozen and trapped in the panel during evacuation. When the temperature reaches a predetermined temperature to be collected, the temperature of the panel becomes 3
It is characterized in that the opening of the motor-operated valve is controlled so as to be higher than the important point or higher than the boiling point.

According to the above configuration, during evacuation, the panel temperature is controlled so as to be always within the optimum temperature range for freezing and collecting water vapor, and the degree of vacuum in the cold trap is stable. Is kept.

According to a seventh aspect of the present invention, in a cold trap for freezing and collecting gas molecules on a panel attached to a heat station of a refrigerator, the cold trap contacts at least one of the heat station and the panel. A heat pipe partially exposed to the outside of the cold trap; and a heater attached to an exposed portion of the heat pipe.

According to the above configuration, when the heater of the heat pipe that is in contact with at least one of the heat station section and the panel is turned on, a heat amount exceeding the refrigerating capacity of the refrigerator is applied to the panel via the heat pipe. Supplied. Then, the temperature of the panel reaches the temperature at which the gas molecules frozen and collected are vaporized, and the regeneration is performed. Thus, the regeneration process is performed without stopping the refrigerator.

According to an eighth aspect of the present invention, in the cold trap according to the seventh aspect of the present invention, there is provided a refrigerant pipe which is in thermal contact with an exposed portion of the heat pipe and through which a refrigerant for cooling the heat pipe flows. It is characterized by having.

According to the above configuration, during evacuation,
By flowing the refrigerant for cooling the heat pipe through the refrigerant pipe that is in thermal contact with the exposed part of the heat pipe, the panel is supplied with a cold energy equal to or higher than the refrigerating capacity of the refrigerator through the heat pipe. In this way, it is possible to shorten the cool-down time at the time of starting and to improve the vacuum exhaust capacity under a high heat load.

According to a ninth aspect of the present invention, in the cold trap according to the eighth aspect of the present invention, a temperature sensor for detecting a temperature of the panel and outputting a signal indicating the detected temperature is provided on the cold pipe. And a controller that receives a signal from the temperature sensor and controls the on / off of the heater or the opening of the motor-operated valve so that the temperature of the panel becomes a predetermined temperature. And

According to the above configuration, if the target temperature of the panel controlled by the controller is set to the temperature at which the gas molecules frozen and collected are vaporized, the panel temperature is controlled by the controller. On / off of the heater is controlled so as to reach a temperature. Thus,
The regeneration process is performed automatically without stopping the refrigerator. On the other hand, if the target temperature of the panel is set to a pre-cooling temperature or a temperature at which gas molecules are frozen and collected by the panel, the controller makes the panel temperature equal to the pre-cooling temperature or the freeze-collecting temperature. Thus, the opening and closing of the electric valve of the refrigerant pipe are controlled. In this way, the cooling down time is automatically reduced or the evacuation capacity under a high heat load is automatically improved.

The invention according to claim 10 is the invention according to claim 9
The method for operating a cold trap according to the invention, wherein, during evacuation, when the temperature of the panel reaches a predetermined temperature at which gas molecules other than water vapor are frozen and collected in the panel, the temperature of the panel is reduced. Is characterized in that the on / off of the heater is controlled so as to be at or above the triple point or the boiling point of a gas other than the water vapor.

According to the above configuration, during the evacuation, the panel temperature is controlled so as to be always within the optimum temperature range for freezing and collecting water vapor, and the degree of vacuum in the cold trap is stabilized. Is kept.

The invention according to claim 11 is the invention according to claim 9
The method of operating a cold trap according to the invention, wherein, during evacuation, when the temperature of the panel does not reach a predetermined temperature range that is optimal for freezing and collecting water vapor on the panel, the temperature of the panel is reduced. The opening degree of the motor-operated valve is controlled so as to fall within the predetermined temperature range.

According to the above configuration, when the heat load is excessive during the vacuum evacuation process, the electric valve of the refrigerant pipe is opened to supply the panel with the amount of cold heat equal to or higher than the refrigerating capacity of the refrigerator. Thus, the evacuation capacity under a high heat load is enhanced, and stable evacuation is performed even under a high heat load.

A vacuum pumping apparatus according to a twelfth aspect of the present invention provides a turbo-molecular pump for compressing gas molecules taken in from an intake port and discharging the compressed gas molecules from an exhaust port, and connected to an inlet port of the turbo-molecular pump, The cold trap according to any one of claims 2, 3, 7, and 8 is provided to supply the gas after freezing and collecting the steam to the intake port of the turbo-molecular pump. It is characterized by.

According to the above configuration, the cold trap and the turbo-molecular pump, which can perform the regeneration process without explosion or the like without stopping the refrigerator to improve the operation rate, are used together with the turbo-molecular pump to provide a high operation rate safety. A simple vacuum exhaust device can be realized. In addition, by using a cold trap and a turbo molecular pump that can supply cooler heat than the refrigerating capacity of the refrigerator and shorten the cool down time and improve the vacuum pumping capacity under high heat load, a higher operating rate can be achieved. A vacuum exhaust device or a high-performance vacuum exhaust device can be realized.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 is a plan view and a side view of the evacuation apparatus according to the present embodiment. This evacuation device includes a cold trap 1 and a turbo molecular pump 2. The cold trap 1 includes a refrigerator 3 and
The refrigerator 3 is roughly composed of a cylindrical enclosure 4 attached to the tip of the refrigerator 3 and a cylindrical panel 6 attached to the heat station 5 of the refrigerator 3 and housed in the enclosure 4. The refrigerator 3 of the cold trap 1 is a one-stage expansion refrigerator using helium gas,
The heat station section 7 is wound around a pipe 8 to which a normal-temperature gas such as a chlorofluorocarbon gas, a helium gas, a nitrogen gas, an oxygen gas or a carbon dioxide gas is supplied. A flange 4b is provided on the lower edge of the enclosure 4, and a flange 2a of an inlet of the turbo-molecular pump 2 is connected to the flange 4b. A vacuum chamber (not shown) of a semiconductor manufacturing apparatus or the like is attached to a flange 4a provided on the upper edge of the enclosure 4 of the cold trap 1 via a gate valve (not shown).

In the vacuum evacuation apparatus having the above-described structure, the panel 6 is moved to 120 by the refrigerator 3 of the cold trap 1.
Water vapor that is cooled to a temperature of K to 150 K and hardly exhausted by the turbo molecular pump 2 in the vacuum chamber is collected by freezing. Further, gas molecules other than water vapor in the vacuum chamber are compressed to a high compression ratio by the turbo molecular pump 2 and exhausted.

In this way, when the water vapor is frozen and collected on the entire surface of the panel 6 of the cold trap 1 and the degree of vacuum is reduced, the nitrogen gas as the heating heat medium is caused to flow through the pipe 8 to refrigerating capacity of the refrigerator 3. Is supplied to the panel 6, and the frozen water molecules are vaporized for regeneration. By doing so, the regeneration process can be performed without stopping the operation of the refrigerator 3, the cool-down time can be shortened, the function suspension period accompanying the regeneration of the cold trap 1 can be shortened, and the operation rate can be improved. As a result, it is possible to improve the operation rate of the vacuum evacuation device including the cold trap 1 and the turbo molecular pump 2. The water vapor vaporized by the regeneration is supplied to a regeneration exhaust port provided in the enclosure 4.
(Not shown).

A nitrogen gas is supplied to the pipe 8 as follows. FIG. 2 is a schematic diagram of a nitrogen gas supply system. The pipe 8 is provided in the flow path 1 in which the electric valve 9 is provided.
0 is connected to the nitrogen cylinder 11. On the other hand, a temperature sensor 12 is attached to the panel 6 (or the heat station 5), and a temperature signal from the temperature sensor 12 is transmitted to a controller 13 such as a microcomputer.
Supplied to Further, a heater 14 is wound around the cold trap 1 in the flow path 10. On / off or opening / closing of the heater 14 and the electric valve 9 are controlled by a control signal from the controller 13.

In the above configuration, after a predetermined regeneration cycle period has elapsed, the controller 13 sets the valve driver 15
And the control signal is sent to open the electric valve 9. In this way, the nitrogen gas is supplied from the nitrogen cylinder 11 to the pipe 8, and the panel 6 is heated to a predetermined temperature (for example, 300K) sufficient to vaporize the frozen water molecules via the heat station unit 7. In this way, the frozen water molecules are vaporized without stopping the operation of the refrigerator 3, and the regeneration process is performed. The controller 13 sends a control signal to the valve driver 15 when a predetermined time has elapsed after detecting that the temperature of the panel 6 has reached the predetermined temperature, based on the temperature signal from the temperature sensor 12. The electric valve 9 is closed. In that case, since the operation of the refrigerator 3 is continued as described above,
The heat station 5 and the panel 6 are quickly cooled, and the panel 6 is cooled to 120K to 1 with a short cool down time.
It can be cooled to a temperature of 50K.

Here, the electric heater is not used in the regeneration control system of the cold trap 1 at all. Therefore, there is no danger associated with the occurrence of short circuit or short circuit due to deterioration of the insulation resistance of the heater. In addition, it is possible to eliminate a rise in running cost due to replacement of the heater and an increase in cost due to installation of a power supply for the heater.

When the panel 6 of the cold trap 1 is to be heated for a shorter time at the time of startup, the controller 13 sends a control signal to the heater driver 16 to turn on the heater 14 and turn on the pipe 8. The nitrogen gas inside is heated. Even in that case, the heater 14 is provided in the flow path 10 outside the cold trap 1. Therefore, there is no danger of explosion when the hydrogen gas in the enclosure 4 comes into direct contact with the filament or the resistance element of the heater 14.

Further, by operating the nitrogen gas supply system for the piping 8 as described below at the time of evacuation, it is possible to perform a more accurate evacuation process. That is, for some reason, the temperature of the panel 6 of the cold trap 1 is a gas other than water vapor having a temperature range of 120 K to 150 K or less which is optimal for freezing and collecting only water vapor (for example, oxygen gas, nitrogen gas, or argon gas). May be cooled to a temperature at which the temperature is frozen and collected on the panel 6. In this case, the gas other than the water vapor does not immediately move to the turbo
As a result, the degree of vacuum of the cold trap 1 fluctuates. Therefore, in such a case, it is necessary to raise the temperature of the panel 6 to at least the triple point or the boiling point of the equivalent gas other than the water vapor. Therefore, the controller 13 performs the following control.

During evacuation, the temperature sensor 12
Panel 6 has a temperature of 120K
Predetermined temperature below the temperature range of 150K (for example, 100K)
, The controller 13 sends a control signal to the valve driver 15 to open the electric valve 9, supplies nitrogen gas to the pipe 8, and heats the panel 6. Then, the opening of the motor-operated valve 9 is controlled so that the temperature of the panel 6 falls within the temperature range of 120 K to 150 K which is equal to or higher than the triple point or higher than the boiling point. Thus, panel 6
Is controlled so that it is always within the optimum temperature range for freezing and collecting water vapor, so that the degree of vacuum in the enclosure 4 is kept stable.

As described above, the vacuum evacuation device constituted by the cold trap 1 and the turbo molecular pump 2 does not provide a heater in the enclosure 4 of the cold trap 1 and does not stop the refrigerator 3. , A reproduction process can be performed. Therefore, there is no danger of explosion due to hydrogen gas coming into direct contact with the heater in the enclosed space due to short circuit or short circuit of the heater,
High availability can be achieved.

FIG. 3 is a plan view of the cold trap 21 different from FIG. The basic structure of the cold trap 21 is the same as that of the cold trap 1 and includes a one-stage expansion refrigerator 22. Then, the heat station section 23 includes any one of a fluorocarbon gas, a helium gas, a nitrogen gas, an oxygen gas, a carbon dioxide gas or the like having a good thermal conductivity.
Heat pipe 2 (preferably helium gas)
4 is wound. A part of the heat pipe 24 is exposed outside the enclosure 25 of the cold trap 21, and a heater 26 is attached to the exposed portion 24a. The on / off of the heater 26 is controlled by a control signal from a controller 27 such as a microcomputer. Further, a temperature sensor 29 is attached to the panel 28, and a temperature signal from the temperature sensor 29 is supplied to the controller 27.

The exposed portion 24 of the heat pipe 24
A part of the refrigerant pipe 30 in which the electric valve 31 is interposed is in thermal contact with a, and the heat pipe 24 and the refrigerant pipe 30
And heat exchange is possible. Note that liquid nitrogen is supplied to the refrigerant pipe 30. In FIG. 3, the position of the heater 26 in the heat pipe 24 and the position of contact with the refrigerant pipe 30 are far away from the enclosure 25 for the sake of simplicity. Improves thermal efficiency.

In the above configuration, when a predetermined reproduction cycle period elapses, the controller 27 sends a control signal to the heater driver 32 to control the turning on and off of the heater 26 based on the temperature signal from the temperature sensor 29. The temperature of the panel 28 is a predetermined temperature sufficient for the frozen water molecules to evaporate.
(For example, 300K), the gas in the heat pipe 24 is heated. In that case, the heater 26 is provided outside the cold trap 21. Therefore, the enclosure 2 is used for the filament and the resistance element of the heater 26.
There is no danger of the hydrogen gas in 5 coming into direct contact and exploding.

In this way, the frozen water molecules are vaporized without stopping the operation of the refrigerator 22 of the cold trap 21, and the regeneration process is performed. Therefore, at the end of the regeneration process, the heat station 23 and the panel 28 are quickly cooled, and the panel 28
It can be cooled to a temperature of K to 150K. That is, according to the present embodiment, it is possible to improve the operation rate by shortening the function suspension period due to the regeneration of the cold trap 21. Further, by providing the heater 26 outside the enclosure 25, the danger of explosion due to contact with the hydrogen gas can be eliminated.

Further, the cold trap 21 can be evacuated with higher precision by operating as follows during evacuation. That is, the temperature of the cold trap 21 at the time of evacuation is 15
If the temperature exceeds 0K, the function of freezing and collecting water vapor decreases. Then, when receiving a high heat load, the following is performed. During the evacuation, the controller 27 determines that the temperature of the panel 28 based on the temperature signal from the temperature sensor 29 is a predetermined temperature (for example, 1) sufficient to freeze and collect water molecules.
If the temperature does not reach 50K), a control signal is sent to the valve driver 33 to open the electric valve 31 and liquid nitrogen is supplied to the refrigerant pipe 30 to supply heat to the heat station section 23 and the panel 2.
8 is further cooled. Then, the temperature of the panel 28 becomes 12
The opening of the electric valve 30 is controlled so as to fall within the temperature range of 0K to 150K. Note that, as in the case of the cold trap 1 shown in FIG.
When the temperature reaches a predetermined temperature (for example, 100K) lower than the temperature range of 150K, the heater 26 is turned on so that the temperature of the panel 28 falls within the temperature range of 120K to 150K, and the degree of vacuum in the enclosure 25 is reduced. It is also possible to keep it stable.

In addition, the cold trap 21 requires 20 to 40 minutes to cool down at the time of startup, which causes a reduction in the operation rate. Therefore, the following processing is performed at the time of startup. That is, the controller 27 sends a control signal to the valve driver 33 to open the electric valve 31 and supplies liquid nitrogen to the refrigerant pipe 30 to pre-cool the panel 28 to a 77K level. Then, when a gate valve (not shown) between the vacuum chamber and the vacuum chamber to be evacuated is opened to start evacuating, the temperature of the panel 28 becomes 120 ° C.
The opening of the electric valve 30 is controlled so as to fall within the temperature range of K to 150K. By doing so, the cool down time at startup can be reduced to about 1/4.

Incidentally, in the cold trap 21 shown in FIG.
The exposed portion 24a of the heat pipe 24 outside the cold trap 21 is brought into thermal contact with a part of the refrigerant pipe 30 in which the electric valve 31 is interposed. Although the cooling function at the time of evacuation is provided, the refrigerant pipe 30 that is in thermal contact with the exposed portion 24a of the heat pipe 24 may be eliminated and only the regeneration processing function may be used.

Also, the liquid nitrogen functioning as the cooling heat medium can be switched and supplied to the pipe 8 of FIGS. 1 and 2 so that the pre-cooling at the time of startup as in the case of the cold trap 21 shown in FIG. It may have a function or a cooling / heating replenishing function under a high heat load. In addition, the cold trap 21 shown in FIG. 3 is combined with the turbo molecular pump 2 shown in FIG. 1 to prevent electric leakage and short-circuit of the heater in an enclosed space and explosion due to direct contact of hydrogen gas with the filament or the resistance element. It is also possible to realize a vacuum pumping device having a high operation rate without danger.

[0050]

As is clear from the above, in the cold trap according to the first aspect of the present invention, the heat medium pipe for flowing the heat medium is brought into contact with at least one of the heat station section and the panel. When a heat medium is supplied, the panel is heated or cooled by heat or cold of the heat medium. Thus, the panel can be heated or cooled without stopping the refrigerator. In that case, no heater is used for heating the panel.
Therefore, it is possible to eliminate the risk and the cost increase associated with the use of the heater.

In the cold trap according to the second aspect of the present invention, the heat medium supplied to the heat medium pipe is a heat medium for heating at least one of the heat station section and the panel. ,
It can supply more heat than the refrigerating capacity of the refrigerator. Therefore, the regeneration process can be performed without stopping the refrigerator, and the cooling down time can be shortened and the operation rate can be improved. In this case, since the heater is not used for heating the panel, danger and cost increase accompanying the use of the heater can be eliminated.

In the cold trap according to the third aspect of the invention, the heat medium supplied to the heat medium pipe is a heat medium for cooling at least one of the heat station section and the panel. ,
It can supply the amount of cold energy that is higher than the freezing capacity of the refrigerator. Therefore, the cool down time at the time of starting can be reduced. Alternatively, the evacuation capacity under a high heat load can be increased.

In the cold trap according to a fourth aspect of the present invention, the temperature of the panel is detected by a temperature sensor, and a controller controls the temperature of the panel to a predetermined temperature based on the detection signal. Since the opening of the electric valve of the heat medium pipe is controlled, the target temperature of the panel is
The temperature is set to a temperature at which the gas molecules frozen and collected are vaporized, and a heating medium for heating is supplied to the heating medium pipe, thereby automatically performing a regeneration process without stopping the refrigerator. Can be.

According to a fifth aspect of the present invention, in the cold trap, the controller turns on / off a heater provided at the protruding portion of the heat medium pipe for flowing the heat medium for heating in accordance with the temperature of the panel. Can be controlled, so that the heater can be turned on during the regeneration process, and the panel can be heated to the vaporization temperature of the gas molecules frozen and collected in the panel in a short time. Thus, it is possible to further shorten the reproduction time and improve the operation rate. In this case, since the heater is provided outside the cold trap, there is no danger of explosion due to direct contact of hydrogen gas with the filament or resistance element of the heater.

The cold trap operating method according to a sixth aspect of the present invention is the cold trap operating method according to the fourth aspect of the present invention, wherein the temperature of the panel is set to a value other than water vapor during evacuation. When the temperature reaches a predetermined temperature at which the gas molecules are frozen and collected, the opening of the electric valve is controlled so that the temperature of the panel becomes equal to or higher than the triple point or the boiling point of the gas other than the water vapor. The panel temperature can be controlled so as to be always within the optimum temperature range for freezing and collecting water vapor, and the degree of vacuum in the cold trap can be kept stable.

Further, in the cold trap according to the present invention, a heat pipe is brought into contact with at least one of the heat station portion and the panel, and a heater is attached to an exposed portion of the heat pipe to the outside of the cold trap. Therefore, by turning on the heater, it is possible to supply heat to the panel that exceeds the refrigerating capacity of the refrigerator. Therefore, the regeneration process can be performed without stopping the refrigerator, and the cool-down time can be reduced. In this case, since the heater is provided outside the cold trap, there is no danger of explosion due to direct contact of hydrogen gas with the filament or resistance element of the heater.

Further, since the refrigerant pipe is in thermal contact with the exposed portion of the heat pipe in the cold trap according to the eighth aspect of the present invention, the refrigerant for cooling the heat pipe is supplied to the refrigerant pipe during evacuation. By flowing
It is possible to supply the panel with a cold energy equal to or higher than the refrigerating capacity of the refrigerator. Therefore, the cool down time at the time of starting can be reduced. Alternatively, the evacuation capacity under a high heat load can be increased.

According to a ninth aspect of the present invention, in the cold trap, the temperature of the panel is detected by a temperature sensor, and the heater is turned on or off by the controller so that the temperature of the panel becomes a predetermined temperature. Since the opening degree of the motor-operated valve provided in the pipe is controlled, the target temperature of the panel is set to a temperature at which the gas molecules being frozen and collected are vaporized, so that the refrigerator is not stopped. , The reproduction process can be performed automatically. On the other hand, by setting the target temperature of the panel to a pre-cooling temperature or a temperature at which gas molecules are frozen and collected in the panel, the cool-down time at the time of start-up is automatically reduced, and the evacuation capacity at the time of a high heat load is automatically set. Can be improved.

According to a tenth aspect of the present invention, there is provided the cold trap operating method according to the ninth aspect, wherein the temperature of the panel other than water vapor is applied to the panel during evacuation. When the temperature reaches a predetermined temperature at which the gas molecules are frozen and collected, the on / off of the heater is controlled so that the temperature of the panel becomes equal to or higher than the triple point or the boiling point of the gas other than the water vapor. The panel temperature can be controlled so as to be always within the optimum temperature range for freezing and collecting water vapor, and the degree of vacuum in the cold trap can be kept stable.

The method for operating a cold trap according to the eleventh aspect is the method for operating a cold trap according to the ninth aspect, wherein:
If the temperature of the panel does not reach a predetermined temperature range that is optimal for freezing and collecting water vapor on the panel, the opening of the motor-operated valve is controlled so that the temperature of the panel falls within the temperature range. Therefore, when the heat load is excessive, the electric valve of the refrigerant pipe can be opened to supply the panel with a cold amount equal to or higher than the refrigerating capacity of the refrigerator. Therefore, it is possible to improve the capability under a high heat load.

The vacuum evacuation apparatus according to claim 12 is connected to a turbo-molecular pump and an intake port of the turbo-molecular pump so that the gas after freezing and collecting the water vapor is supplied to the turbo-molecular pump. Since the cold trap according to any one of claims 2, 3, 7, and 8 is used in combination with the cold trap, the refrigerator can be safely regenerated without stopping the refrigerator without using a heater. By using a cold trap and a turbo-molecular pump that can improve the operation rate by performing the processing, it is possible to realize a safe vacuum evacuation device with a high operation rate. In addition, the use of a cold trap and a turbo molecular pump, which can supply the amount of cooling heat equal to or higher than the refrigerating capacity of the refrigerator to shorten the cool-down time at startup and improve the evacuation capacity at high heat load, It is possible to realize a vacuum pumping device with a high operation rate and a high capacity vacuum pumping device.

[Brief description of the drawings]

FIG. 1 is a plan view and a side view of a vacuum exhaust device of the present invention.

FIG. 2 is a schematic view of a nitrogen gas supply system for supplying nitrogen gas to the pipe of FIG.

FIG. 3 is a plan view of a cold trap different from the cold trap in FIGS. 1 and 2;

[Explanation of symbols]

1,21 ... cold trap, 2 ... turbo molecular pump, 6,28 ... panel, 7,23 ...
Heat station part, 8 ... piping,
9, 31 ... electric valve, 10 ... flow path,
11: nitrogen cylinder, 12, 29: temperature sensor,
13, 27: controller, 14, 26: heater, 24: heat pipe, 30: refrigerant pipe.

Claims (12)

[Claims] 1. A heat station section (7) of a refrigerator (3).
In the cold trap (1) for freezing and collecting gas molecules on the panel (6) attached to the panel, the heat station (7) or the panel (6)
A cold trap, wherein a heat medium pipe (8) for flowing a heat medium is brought into contact with at least one of them. 2. The cold trap according to claim 1, wherein the heat medium is a heat medium for heating at least one of the heat station section (7) and the panel (6). trap. 3. The cold trap according to claim 1, wherein the heat medium is a heat medium for cooling at least one of the heat station section (7) and the panel (6). trap. 4. The cold trap (1) according to claim 2, wherein the heat medium pipe (8) projects outside the cold trap (1), and the heat medium pipe (8) (9) Electric valve (9)
A temperature sensor (12) for detecting a temperature of the panel (6) and outputting a signal representing the detected temperature; and receiving a signal from the temperature sensor (12),
A cold trap, comprising: a controller (13) for controlling the opening of the electric valve (9) so that the temperature of (6) becomes a predetermined temperature. 5. The cold trap (1) according to claim 4,
In the above, a heater (14) provided at the projecting portion of the heating medium pipe (8) through which the heating heating medium flows is provided, and the controller (13) is provided with the heater according to the temperature of the panel (6). (14) A cold trap, characterized in that on / off of the cold trap can be controlled. 6. The cold trap according to claim 4.
The method according to (1), wherein, during evacuation, when the temperature of the panel (6) reaches a predetermined temperature at which gas molecules other than water vapor are frozen and collected in the panel (6), A method for operating a cold trap, comprising controlling the opening of the motor-operated valve (9) such that the temperature of the panel (6) is equal to or higher than the triple point or the boiling point of the gas other than the steam. 7. A heat station section of the refrigerator (22)
In the cold trap (21) for freezing and collecting gas molecules on the panel (28) attached to the (23), the heat station section (23) or the panel
The heat pipe (24), which is in contact with at least one of (28) and partially exposed outside the cold trap (21), is attached to the exposed portion (24a) of the heat pipe (24). A cold trap comprising a heater (26). 8. The cold trap (2) according to claim 7,
The cold pipe according to 1), further comprising a refrigerant pipe (30) for thermally contacting an exposed portion (24a) of the heat pipe (24) and for flowing a cooling medium for cooling the heat pipe (24). trap. 9. The cold trap (2) according to claim 8,
In 1), a temperature sensor (29) for detecting a temperature of the panel (28) and outputting a signal representing the detected temperature; an electric valve (31) provided in the refrigerant pipe (30); Upon receiving a signal from the sensor (29), the panel
The heater (26) so that the temperature of (28) becomes a predetermined temperature.
A cold trap provided with a controller (27) for controlling the turning on / off of the electric valve or the opening of the electric valve (31). 10. The cold trap according to claim 9,
(21) The method according to (21), wherein, during evacuation, when the temperature of the panel (28) reaches a predetermined temperature at which gas molecules other than water vapor are frozen and collected on the panel (28), A method for operating a cold trap, characterized in that the on / off of the heater (26) is controlled so that the temperature of the panel (28) is at or above the triple point or the boiling point of a gas other than water vapor. 11. The cold trap according to claim 9,
In the operation method of (21), when the temperature of the panel (28) does not reach a predetermined temperature range that is optimal for freezing and collecting steam on the panel (28) during evacuation, A method of operating a vacuum exhaust device, comprising controlling an opening of the electric valve (31) such that a temperature of the panel (28) falls within the predetermined temperature range. 12. A turbo-molecular pump (2) for compressing gas molecules taken in from an intake port and discharging it from an exhaust port, and connected to an intake port of the turbo-molecular pump (2) to freeze and collect water vapor. After the gas, the above turbo molecular pump (2)
The cold trap (1, 1) according to any one of claims 2, 3, 7, 7 or 8 for supplying the cold trap (1,
21) A vacuum evacuation device comprising: