Cryogenic system and vacuum treatment method

Abstract

To provide a cryogenic system and a vacuum treatment method capable of enhancing accuracy in maintaining an exhaust speed in a cryopump.SOLUTION: A height of a thermal shield 11 is a first height H11. In a region defined by the thermal shield 11 and a baffle 13, a region from an opening 11A of the thermal shield 11 to 1 / 2 of the first height H11 is a temperature adjustment region 10S. At least one of a portion included in the temperature adjustment region 10S of the thermal shield 11 and the baffle 13 is a heating object. A cryogenic system 1 includes a temperature sensor 15 located in the temperature adjustment region 10S, a heating unit 16 for heating the heating object, and a control unit 20 for controlling driving of the heating unit 16. The control unit 20 controls the driving of the heating unit 16 so that a temperature of the baffle 13 becomes a prescribed value on the basis of a detected value of the temperature sensor 15.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a cryosystem and a vacuum processing method. [Background technology]

[0002] One example of a cryopump includes a two-stage refrigerator with a first cooling stage and a second cooling stage. The cryopump includes a first temperature sensor that detects the temperature of the first cooling stage, a second temperature sensor that detects the temperature of the second cooling stage, and a heater that heats the first cooling stage. In the cryopump, if the temperature of the first cooling stage falls below a target value even when the frequency of the driving power supply is set to the minimum value, the heater is activated to raise the temperature of the first cooling stage to the target value. If the temperature of the second cooling stage exceeds the target value, the heater is activated to heat the first cooling stage so that the temperature of the first cooling stage exceeds the target value. This increases the frequency of the driving power supply, resulting in a decrease in the temperature of the second cooling stage (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-292103 Summary of the Invention [Problem to be solved by the invention]

[0004] Vacuum processing equipment for performing various processes such as film deposition is required to maintain the pressure within the processing space defined by the chamber with high precision, which in turn requires cryopumps to maintain pumping speeds with high precision. [Means for solving the problem]

[0005] A cryosystem for solving the above problems includes a cylindrical thermal shield having an opening at one end, a cryopanel housed within the thermal shield, a baffle located at the opening of the thermal shield, and a cryopump equipped with a refrigerator configured to cool the thermal shield and the thermal shield. The height of the thermal shield is a first height. Of the area defined by the thermal shield and the baffle, an area from the opening of the thermal shield to half of the first height is a temperature control area. At least one of the portion of the thermal shield included in the temperature control area and the baffle is a heated part. The cryosystem includes a temperature sensor located within the temperature control area, a heating unit that heats the heated part, and a control unit that controls the operation of the heating unit. The control unit is configured to control the operation of the heating unit based on the detection value of the temperature sensor so that the temperature of the baffle reaches a predetermined value.

[0006] A vacuum processing method for solving the above problem is a vacuum processing method in which a process gas is supplied to a chamber and the process gas is exhausted from the chamber using a cryopump connected to the chamber. The height of a thermal shield provided in the cryopump is a first height. Of the area defined by the thermal shield and a baffle, an area from an opening in the thermal shield to 1 / 2 of the first height is a temperature control area. At least one of a portion of the thermal shield included in the temperature control area and the baffle is a heated part. The temperature within the temperature control area is detected, and the heated part is heated so that the temperature of the baffle reaches a predetermined value.

[0007] In a cryopump, the baffle has an inlet for the process gas pumped from the chamber to which the cryopump is connected. Therefore, when pumping of the process gas begins, the temperature of the baffle fluctuates before the temperature of the heat shield and the cryopanels located within the heat shield fluctuate. According to the above-described cryosystem and vacuum processing method, the baffle temperature is controlled based on a detected temperature value obtained near the baffle, thereby minimizing deviation of the actual baffle temperature from the target value. This minimizes fluctuations in the temperature of the baffle that introduces the process gas, thereby minimizing changes in the flow of the process gas into the heat shield. As a result, the accuracy of maintaining the pumping speed of the cryopump is improved.

[0008] In the above-described cryosystem, the part to be heated may be the baffle, the temperature sensor may be attached to the baffle to detect the temperature of the baffle, and the heating unit may be attached to the baffle to heat the baffle.

[0009] According to the above cryosystem, the baffle is directly heated based on the detected value of the baffle temperature, so that the baffle temperature can be controlled with even greater precision.

[0010] In the above-mentioned cryosystem, the heating target part may be a part of the thermal shield that is included in the temperature control area, the temperature sensor may be attached to the baffle to detect the temperature of the baffle, and the refrigerator may be the heating part.

[0011] According to the above-described cryosystem, the baffle is heated via a heat shield using a refrigerator provided in the cryopump based on the detected value of the baffle temperature, so that the baffle temperature can be accurately controlled without providing a heating section for heating the baffle.

[0012] In the above cryosystem, the predetermined value may be within a range of 60K or more and 130K or less. According to the above-described cryosystem, it is possible to improve the effectiveness of stabilizing the pumping speed of the cryopump. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a system configuration diagram showing a cryosystem according to the first embodiment. [Figure 2] FIG. 2 is a graph showing the change in chamber pressure over time for Test Example 1. [Figure 3] FIG. 3 is a graph showing the change over time in the pumping speed of the cryopump for Test Example 1. [Figure 4] FIG. 4 is a graph showing the rate of change in the pumping speed of the cryopump for Test Example 1. [Figure 5] FIG. 5 is a graph showing the change in chamber pressure over time for Test Example 2. [Figure 6] FIG. 6 is a graph showing the change over time in the pumping speed of the cryopump for Test Example 2. [Figure 7] FIG. 7 is a graph showing the change over time in the pumping speed of the cryopump for Test Example 2. [Figure 8] FIG. 8 is a system configuration diagram showing a cryosystem according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] [First embodiment] A first embodiment of a cryosystem and a vacuum processing method will be described with reference to FIG. [Cryosystem] 1, the cryosystem 1 includes a cryopump 10 and a control unit 20. The cryopump 10 includes a heat shield 11, a cryopanel 12, a baffle 13, and a refrigerator 14.

[0015] The thermal shield 11 has a cylindrical shape and has an opening 11A at one end. The cryopanels 12 are housed inside the thermal shield 11. The baffle 13 is located in the opening 11A of the thermal shield 11. The refrigerator 14 is configured to be able to cool the thermal shield 11 and the cryopanels 12.

[0016] The height of the thermal shield 11 is a first height H11. Of the area defined by the thermal shield 11 and the baffle 13, the area from the opening 11A of the thermal shield 11 to 1 / 2 (H11 / 2) of the first height H11 is the temperature control area 10S. At least one of the part of the thermal shield 11 included in the temperature control area 10S and the baffle 13 is the heating target. The cryosystem 1 further includes a temperature sensor 15 and a heating unit 16. The temperature sensor 15 is located within the temperature control area 10S. The heating unit 16 heats the heating target.

[0017] Of a pair of surfaces of the baffle 13 facing each other in the thickness direction, the surface facing the cryopanel 12 is the back surface 13R, and the surface opposite the back surface 13R is the front surface 13F. In this embodiment, the temperature sensor 15 is attached to the back surface 13R of the baffle 13. As a result, the temperature sensor 15 is located within the temperature control region 10S.

[0018] In this embodiment, the heating unit 16 is also attached to the rear surface 13R of the baffle 13. In the example shown in Fig. 1, the cryo-system 1 includes two heating units 16. The cryo-system 1 may include one or more heating units 16.

[0019] The baffle 13 may be a circular perforated plate. When viewed from a viewpoint facing the surface 13F of the baffle 13, the temperature sensor 15 may be located in a central portion including the center of the baffle 13. Two heating units 16 may be arranged along the diameter of the baffle 13 to sandwich the temperature sensor 15. This reduces variations in the degree of heating within the surface of the baffle 13 and makes it difficult for the detected value of the temperature sensor 15 to reflect the temperature of a local area of ​​the baffle 13. Note that it is preferable that the distances between each heating unit 16 and the temperature sensor 15 are equal to each other.

[0020] The control unit 20 controls the driving of the heating unit 16. The control unit 20 is configured to control the driving of the heating unit 16 based on the detection value of the temperature sensor 15 so that the temperature of the baffle 13 becomes a predetermined value.

[0021] The control unit 20 is electrically connected to the temperature sensor 15 and each heating unit 16. The control unit 20 receives the detected value output by the temperature sensor 15. The control unit 20 generates a control signal for controlling the driving of the heating unit 16 based on the detected value of the temperature sensor 15. The control unit 20 outputs the control signal to each heating unit 16. The heating unit 16 is driven based on the control signal.

[0022] The control unit 20 includes electronic circuits such as a CPU and an MPU. The control unit 20 includes storage such as an SSD and an HDD. The control unit 20 includes memory such as a ROM, a RAM, and a registered memory. The control unit 20 may include an integrated circuit such as an ASIC or an FPGA. All of the processing performed by the control unit 20 may be performed by software included in the control unit 20, or by a combination of an integrated circuit and software included in the control unit 20.

[0023] The cryopump 10 is connected to a chamber C provided in the vacuum processing apparatus. When the cryopump 10 is driven, the chamber C is evacuated. Note that the cryopump 10 cannot evacuate the pressure in the chamber C from atmospheric pressure. Therefore, the chamber C is evacuated to a pressure lower than atmospheric pressure by a coarse pump (not shown) connected to the chamber C, and then the cryopump 10 evacuates the chamber C.

[0024] In the cryopump 10, the baffle 13 has an inlet for the process gas pumped from the chamber C to which the cryopump 10 is connected. Therefore, when pumping of the process gas begins, the temperature of the baffle 13 drops before the temperature of the heat shield 11 and the cryopanels 12 located within the heat shield 11. According to the cryosystem 1, the temperature of the baffle 13 is controlled based on a detected temperature value obtained near the baffle 13, thereby making it possible to reduce deviations in the actual temperature of the baffle 13 from the target temperature of the baffle 13. As a result, the temperature of the baffle 13, which introduces the process gas, is less likely to fluctuate, thereby reducing changes in the inflow of the process gas into the heat shield 11. As a result, the accuracy of maintaining the pumping speed of the cryopump 10 is improved.

[0025] As described above, in this embodiment, the baffle 13 is the part to be heated. Since the baffle 13 is in contact with the heat shield 11, the heat given to the baffle 13 by the heating unit 16 is also supplied to the heat shield 11 via the baffle 13. However, of the part of the heat shield 11 and the baffle 13, the part that is primarily heated by the heating unit 16 is the baffle 13. Furthermore, the temperature sensor 15 is attached to the baffle 13, thereby detecting the temperature of the baffle 13. The heating unit 16 is attached to the baffle 13, thereby heating the baffle 13. Because the baffle 13 is directly heated based on the detected temperature value of the baffle 13, the temperature of the baffle 13 can be controlled with even greater precision.

[0026] The predetermined value for the temperature of the baffle 13 may be within the range of 60 K to 130 K. This can improve the effectiveness of stabilizing the pumping speed of the cryopump 10.

[0027] The refrigerator 14 of the cryopump 10 may be, for example, a Gifford-McMahon (GM) refrigerator. The refrigerator 14 includes a first stage 14A and a second stage 14B. While the refrigerator 14 is operating, the temperature of the second stage 14B is lower than the temperature of the first stage 14A. The temperature of the first stage 14A may be, for example, 50 K or higher and 110 K or lower. The temperature of the second stage 14B may be, for example, 10 K or higher and 20 K or lower. The refrigerator 14 includes a first cylinder 14C and a second cylinder 14D. The first cylinder 14C is connected to the first stage 14A. The second cylinder 14D is connected to the first stage 14A and the second stage 14B.

[0028] The refrigerator 14 is equipped with a motor 14M. When the motor 14M rotates, adiabatic expansion occurs in the expansion chamber of the refrigerator 14, thereby cooling the first stage 14A and the second stage 14B of the refrigerator 14.

[0029] The cryopump 10 includes a pump case 17. The pump case 17 houses the refrigerator 14. The pump case 17 includes a first cylindrical portion 17A and a second cylindrical portion 17B connected to the first cylindrical portion 17A. The first cylindrical portion 17A houses a first cylinder 14C and a first stage 14A. The second cylindrical portion 17B houses a second cylinder 14D and a second stage 14B.

[0030] The thermal shield 11 is connected to the first stage 14A. During the operation of the refrigerator 14, the temperature of the thermal shield 11 is approximately equal to the temperature of the first stage 14A. The cryopump 10 includes a plurality of cryopanels 12. Each cryopanel 12 is connected to the second stage 14B. During the operation of the refrigerator 14, the temperature of each cryopanel 12 is approximately equal to the temperature of the second stage 14B.

[0031] [Vacuum processing method] The vacuum processing method is a processing method in which a process gas is evacuated from a chamber C to which the process gas is supplied using a cryopump 10 connected to the chamber C. In the vacuum processing method of the present disclosure, the temperature in the temperature control region 10S is detected, and a heating target is heated so that the temperature of the baffle 13 reaches a predetermined value. In this embodiment, as described above, the temperature of the baffle 13 is detected as the temperature in the temperature control region 10S, and the baffle 13 is the heating target.

[0032] In a vacuum processing apparatus equipped with the cryopump 10, the temperature of the baffle 13 may not be stable while several processing objects are being processed. While the temperature of the baffle 13 is not stable, the pumping speed of the cryopump 10 is also not stable. In the vacuum processing method, when the supply of the process gas is started, the temperature of the baffle 13 may be controlled, that is, the temperature in the temperature control region 10S may be detected, and the heating object may be heated so that the temperature of the baffle 13 reaches a predetermined value.

[0033] For example, temperature control of the baffle 13 may be started when the supply of the process gas is started, or may be started a predetermined time before the supply of the process gas is started. This makes it possible to stably maintain the temperature of the baffle 13, and therefore the pumping speed of the cryopump 10, from the time the supply of the process gas is started. From the viewpoint of maintaining the temperature of the baffle 13 with higher accuracy, it is preferable to start temperature control of the baffle 13 a predetermined time before the supply of the process gas is started.

[0034] Furthermore, if there is an interruption in the processing of the object to be processed in the vacuum processing apparatus, the temperature of the baffle 13 changes during the interruption compared to during the processing. Therefore, the temperature control of the baffle 13 may be continued even during the interruption of the processing. Alternatively, the temperature control of the baffle 13 may be started after a predetermined period of interruption, for example, one hour or more, has elapsed.

[0035] From the viewpoint of reducing power consumption in the vacuum processing apparatus, it is preferable to stop adjusting the temperature of the baffle 13 while the supply of the process gas is stopped.

[0036] [Test example] A test example of the cryo-system 1 will be described with reference to FIGS. [Test Example 1] A cryopump 10 was used, which had a temperature sensor 15 attached to the baffle 13 and two heating elements 16 attached to the baffle 13. Using the value detected by the temperature sensor 15, the temperature of the baffle 13 was controlled using a control unit 20 so as to maintain the temperature of the baffle 13 at 100 K. Argon gas was used as the process gas. In addition, a test dome, gas inlet, and connecting piping were used that conformed to JIS B 8329-1:2015 "Vacuum Technology - Performance Test Methods for Vacuum Pumps - Part 1: Common Test Methods."

[0037] [Test Example 2] In Test Example 1, the temperature of the baffle 13 was adjusted so as to maintain the temperature of the baffle 13 at 100K in the same manner as in Test Example 1, except that the heating section 16 was changed to a heating section attached to the first stage 14A and heating the first stage 14A.

[0038] [Evaluation results] In Test Example 1, the results of measuring the pressure (Pa) of chamber C were as shown in Figure 2, the results of measuring the pumping speed (L / sec) of the cryopump 10 were as shown in Figure 3, and the rate of change in the pumping speed was as shown in Figure 4. In contrast, in Test Example 2, the results of measuring the pressure of chamber C were as shown in Figure 5, the results of measuring the pumping speed of the cryopump were as shown in Figure 6, and the rate of change in the pumping speed was as shown in Figure 7.

[0039] In both Test Example 1 and Test Example 2, measurements of the pressure in chamber C and the pumping speed of cryopump 10 began when the operation of cryopump 10 was started. In both Test Example 1 and Test Example 2, the supply of process gas to chamber C began 5 minutes after the operation of cryopump 10 was started. Measurements of the pressure in chamber C and the pumping speed of cryopump 10 were also conducted over a period of 47 minutes from the time the operation of cryopump 10 was started.

[0040] As shown in Figure 2, in Test Example 1, it was confirmed that the pressure in chamber C was maintained approximately constant. Also, as shown in Figure 3, it was confirmed that the pumping speed of cryopump 10 was maintained approximately constant in Test Example 1. Also, as shown in Figure 4, it was confirmed that the maximum rate of change in the pumping speed of cryopump 10 was 0% in Test Example 1.

[0041] As shown in Figure 5, in Test Example 2, the pressure in Chamber C increased from 5 to 20 minutes and remained almost constant after 20 minutes. Also, as shown in Figure 6, in Test Example 2, the pumping speed of the cryopump decreased from 5 to 20 minutes and remained almost constant after 20 minutes. Also, as shown in Figure 7, in Test Example 2, the maximum rate of change in the pumping speed of the cryopump was approximately 5%.

[0042] Thus, it was found that the cryopump 10 equipped with the temperature sensor 15 for measuring the temperature of the baffle 13 and the heating unit 16 for heating the baffle 13 can suppress changes in the pumping speed of the cryopump 10 and changes in the pressure of the chamber C. Compared to the temperature control of the baffle 13 in Test Example 2, the temperature control of the baffle 13 in Test Example 1 is less likely to cause a delay in the temperature control relative to the cooling of the baffle 13, and therefore it can be said that the temperature of the baffle 13 can be maintained more stably.

[0043] As described above, according to the first embodiment of the cryosystem and vacuum processing method, the following effects can be obtained. (1-1) The temperature of the baffle 13 is controlled based on the detected temperature value obtained near the baffle 13, which makes it possible to reduce the deviation of the actual temperature of the baffle 13 from the target temperature of the baffle 13. This reduces the temperature fluctuation of the baffle 13, which introduces the process gas, and therefore reduces changes in the inflow of the process gas into the heat shield 11. As a result, the accuracy of maintaining the pumping speed of the cryopump 10 is improved.

[0044] (1-2) Since the baffle 13 is directly heated based on the detected temperature of the baffle 13, the temperature of the baffle 13 can be controlled with even greater precision.

[0045] (1-3) When the predetermined value is equal to or greater than 60K and equal to or less than 130K, the effectiveness of stabilizing the pumping speed of the cryopump 10 can be improved.

[0046] [Second embodiment] A second embodiment of a cryosystem and a vacuum processing method will be described with reference to Figure 8. The second embodiment differs from the first embodiment in the configuration related to heating the baffle. Therefore, while these differences will be described in detail below, components common to the first and second embodiments will be denoted by the same reference numerals as in the first embodiment, and detailed descriptions of these components will be omitted.

[0047] [Cryosystem] 8, the cryosystem 1 of this embodiment does not include the heating unit 16 that is included in the cryosystem 1 of the first embodiment. The refrigerator 14 of the cryopump 30 includes an inverter 31 electrically connected to a motor 14M.

[0048] In this embodiment, the control unit 20 is electrically connected to the temperature sensor 15 and the inverter 31. The control unit 20 determines the operating frequency of the motor 14M in accordance with the detected value of the temperature sensor 15. The control unit 20 outputs a control signal related to the determined operating frequency of the motor 14M to the inverter 31.

[0049] The inverter 31 is configured to be able to control the operating frequency, i.e., the rotation speed, of the motor 14M. The inverter 31 converts the power input to the motor 14M into power corresponding to the control signal output by the control unit 20, and then outputs the converted power to the motor 14M. The motor 14M is driven at an operating frequency corresponding to the power output by the inverter 31.

[0050] Increasing the operating frequency of motor 14M increases the frequency of the thermal cycle in refrigerator 14. This cools first stage 14A, causing the temperature of heat shield 11 connected to first stage 14A to decrease. Conversely, lowering the operating frequency of motor 14M also decreases the frequency of the thermal cycle in refrigerator 14. This increases the temperature of first stage 14A, causing the temperature of heat shield 11 connected to first stage 14A to increase.

[0051] In the cryosystem 1 of this embodiment, the portion of the thermal shield 11 included in the temperature control region 10S is the heating target. Note that, since the thermal shield 11 is in contact with the baffle 13, the heat given to the thermal shield 11 by the first stage 14A is also supplied to the baffle 13 via the thermal shield 11. However, of the part of the thermal shield 11 and the baffle 13, the component that is primarily heated by the first stage 14A is the thermal shield 11.

[0052] Similar to the cryosystem 1 of the first embodiment, the temperature sensor 15 is attached to the baffle 13 and detects the temperature of the baffle 13. The refrigerator 14 is a heating unit that heats the heating target. Based on the detected temperature of the baffle 13, the refrigerator 14 included in the cryopump 30 is used to heat the baffle 13 via the heat shield 11. Therefore, the temperature of the baffle 13 can be accurately controlled without providing a heating unit for heating the baffle 13.

[0053] As with the cryosystem 1 of the first embodiment, it is preferable to adjust the temperature of the baffle 13 while processing is being performed in the vacuum processing apparatus, that is, while the process gas is being supplied to the chamber C.

[0054] The flow rate of the gas contacting the first stage 14A is smaller than the flow rate of the gas contacting the baffle 13. Therefore, even if the temperature of the first stage 14A is controlled to a temperature that maintains the temperature of the baffle 13 at a predetermined value, the temperature of the first stage 14A is less likely to affect the pumping speed of the cryopump 10 than the temperature of the baffle 13.

[0055] However, for example, if the temperature of first stage 14A exceeds a predetermined value, the temperature control of baffle 13 using refrigerator 14 may be switched to control for maintaining the temperature of first stage 14A at a predetermined value. In this case, control for maintaining the temperature of first stage 14A at a predetermined value may be performed based on the detected value of the temperature of first stage 14A.

[0056] Alternatively, if the temperature of first stage 14A falls below a predetermined value for some reason while the temperature of baffle 13 is being controlled, control may be switched from temperature control of baffle 13 to control for maintaining the temperature of first stage 14A at a predetermined value. In this case, control for maintaining the temperature of first stage 14A at a predetermined value may be performed based on the detected value of the temperature of first stage 14A.

[0057] As described above, according to the second embodiment of the cryosystem and vacuum processing method, in addition to the above-mentioned (1-1) and (1-3), the following effects can be obtained. (2-1) Based on the detected temperature of the baffle 13, the refrigerator 14 included in the cryopump 30 is used to heat the baffle 13 via the heat shield 11. This allows the temperature of the baffle 13 to be accurately controlled without providing a heating unit for heating the baffle 13.

[0058] The above-described embodiments may be modified as follows. [Temperature sensor] The position where the temperature sensor 15 is attached is not limited to the rear surface 13R of the baffle 13. The temperature sensor 15 may be disposed within the temperature control region 10S described above.

[0059] [Vacuum processing] The vacuum processing performed in the vacuum processing apparatus may be a film formation process or an etching process. The film formation process may be, for example, PVD or CVD.

[0060] [Combination of embodiments] The configuration of the first embodiment may be combined with the configuration of the second embodiment. That is, the cryosystem 1 of the second embodiment may include a heating unit 16 attached to the baffle 13. In this case, while the process gas is being supplied, heating of the baffle 13 using the heating unit 16 and heating of the baffle 13 using the refrigerator 14 may be switched.

[0061] For example, the baffle 13 may be heated using the heating unit 16 until a predetermined period of time has elapsed since the supply of the process gas started, and after the predetermined period of time has elapsed, the baffle 13 may be heated using the refrigerator 14. In this case, more responsive temperature control is performed during the period when the baffle 13 is likely to be cooled by the exhaust of the process gas, making it easier to maintain a stable temperature of the baffle 13.

[0062] Alternatively, the period during which the temperature of the baffle 13 is adjusted may include a period during which both heating of the baffle 13 using the heating unit 16 and heating of the baffle 13 using the refrigerator 14 are performed. [Explanation of symbols]

[0063] 1... Cryosystem 10...Cryopump 11...Heat shield 12...Cryopanel 13...Baffle 14...Freezer 15...Temperature sensor 16...Heating part 20...Control unit C...Chamber

Claims

1. a cylindrical heat shield having an opening at one end; a cryopanel housed within the thermal shield; a baffle located at the opening in the heat shield; a cryopump including a refrigerator configured to be able to cool the thermal shield and the cryopanel, the heat shield has a first height; a temperature control region in a region defined by the heat shield and the baffle, the region being from an opening of the heat shield to half of the first height; At least one of a portion of the heat shield included in the temperature control region and the baffle is a heating target, a temperature sensor located within the temperature control area; a heating unit that heats the heating target portion; a control unit that controls the driving of the heating unit, The control unit is configured to control driving of the heating unit based on a detection value of the temperature sensor so that the temperature of the baffle reaches a predetermined value. Cryo system.

2. the heating target is the baffle, the temperature sensor is attached to the baffle to detect the temperature of the baffle; The heating unit is attached to the baffle and heats the baffle. The cryosystem of claim 1 .

3. the heating target portion is a portion of the thermal shield that is included in the temperature control region, the temperature sensor is attached to the baffle to detect the temperature of the baffle; The refrigerator is the heating unit. The cryosystem of claim 1 .

4. The predetermined value is within the range of 60K to 130K. A cryosystem according to any one of claims 1 to 3.

5. 1. A vacuum processing method for exhausting a process gas from a chamber using a cryopump connected to the chamber to which the process gas is supplied, the method comprising: a height of a heat shield included in the cryopump is a first height; a temperature control region in a region defined by the heat shield and the baffle, the region being from the opening of the heat shield to half of the first height; At least one of a portion of the heat shield included in the temperature control region and the baffle is a heating target, The temperature in the temperature control area is detected, and the heating target portion is heated so that the temperature of the baffle reaches a predetermined value. Vacuum processing method.

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