Cryogenic system and vacuum treatment method

Abstract

The invention provides a cryogenic system and a vacuum processing method, which can improve the maintaining precision of the exhaust speed in a cryopump. The height of the heat shield (11) is a first height (H11). Among the regions defined by the heat shield case (11) and the baffle (13), a region extending from the opening (11A) of the heat shield case (11) to 1 / 2 of the first height (H11) is a temperature adjustment region (10S). At least one of a portion of the heat shield (11) included in the temperature adjustment region (10S) and the baffle (13) is a portion to be heated. A cryogenic system (1) is provided with: a temperature sensor (15) positioned within a temperature adjustment region (10S); a heating unit (16) that heats the portion to be heated; and a control unit (20) that controls the driving of the heating unit (16). The control unit (20) controls the driving of the heating unit (16) on the basis of the value detected by the temperature sensor (15) so that the temperature of the shutter (13) becomes a prescribed value.

Description

Technical Field

[0001] The invention relates to a low temperature system and a vacuum processing method. Background Art

[0002] An example of a cryogenic pump includes a two-stage refrigerator, and the two-stage refrigerator includes a first cooling stage and a second cooling stage. The cryogenic pump includes a first temperature sensor for detecting the temperature of the first cooling stage, a second temperature sensor for detecting the temperature of the second cooling stage, and a heater for heating the first cooling stage. In the cryogenic pump, when the temperature of the first cooling stage is lower than the target value even when the frequency of the driving power supply is set to the minimum value, the temperature of the first cooling stage is raised to the target value by driving the heater. In addition, when the temperature of the second cooling stage exceeds the target value, the temperature of the first cooling stage is heated by driving the heater so that the temperature of the first cooling stage exceeds the target value. As a result, the frequency of the driving power supply is increased, and as a result, the temperature of the second cooling stage is reduced (for example, see Patent Document 1). Prior art literature Patent Literature

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

[0004] However, in vacuum processing apparatuses that perform various processes such as film formation, it is required to maintain the pressure within the processing space defined by the chamber with higher precision. Consequently, cryopumps are required to maintain the pumping speed with higher precision. Solutions to Problems

[0005] In one aspect, a cryogenic system includes a cryogenic pump, the cryogenic pump including: a heat shield having a cylindrical shape and an opening at one end; a cryogenic panel housed within the heat shield; a baffle located at the opening of the heat shield; and a refrigerator configured to cool the heat shield and the cryogenic panel. The height of the heat shield is a first height. An area defined by the heat shield and the baffle, the area from the opening of the heat shield to 1 / 2 of the first height, is a temperature control area. At least one of the portion of the heat shield included in the temperature control area and the baffle is a heating target portion. The cryogenic system includes: a temperature sensor located within the temperature control area; a heating unit that heats the heating target portion; and a control unit that controls the driving of the heating unit. The control unit is configured to control the driving of the heating unit based on the detection value of the temperature sensor so that the temperature of the baffle reaches a specified value.

[0006] In one aspect, a vacuum processing method uses a cryogenic pump connected to a chamber for supplying a process gas to discharge the process gas from the chamber. The height of the heat shield provided by the cryogenic pump is a first height. The area from the opening of the heat shield to 1 / 2 of the first height in the area defined by the heat shield and the baffle is a temperature control area. At least one of the portion of the heat shield included in the temperature control area and the baffle is a heating target portion. 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 specified value.

[0007] In a cryopump, a baffle has an inlet for process gas exhausted from a chamber connected to the cryopump. Therefore, when exhaust of the process gas begins, the temperature of the baffle changes before that of the heat shield and the cryogenic panel located within the heat shield. According to the aforementioned cryogenic system and vacuum processing method, the temperature of the baffle is controlled based on a temperature detection value obtained near the baffle, thereby suppressing deviations in the actual baffle temperature from the target baffle value. As a result, since the temperature of the baffle, which introduces the process gas, is less likely to fluctuate, variations in the flow of process gas into the heat shield can be suppressed, resulting in improved accuracy in maintaining the exhaust speed within the cryopump.

[0008] In the above-described low-temperature system, the heating target portion may be the baffle, the temperature sensor may be mounted on the baffle to detect a temperature of the baffle, and the heating portion may be mounted on the baffle to heat the baffle.

[0009] According to the above-described low-temperature system, since the baffle is directly heated based on the detected value of the temperature of the baffle, the temperature of the baffle can be controlled with higher accuracy.

[0010] In the low-temperature system, the heating target portion may be a portion of the heat shield included in the temperature adjustment region, the temperature sensor may be attached to the baffle to detect a temperature of the baffle, and the refrigerator may be the heating portion.

[0011] According to the cryogenic system, the baffle is heated via the heat shield using the refrigerator included in the cryopump based on the detected value of the baffle temperature. Therefore, a heating unit for heating the baffle is not provided, and the temperature of the baffle can be controlled with high precision.

[0012] In the low-temperature system, the predetermined value may be within a range of 60K to 130K. According to the above-described cryogenic system, the effectiveness of stabilizing the pumping speed of the cryopump can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1This is a system configuration diagram showing a low-temperature system according to the first embodiment. Figure 2 This is a graph showing the temporal change in the pressure of the chamber in Test Example 1. Figure 3 This is a graph showing the temporal change in the pumping speed of the cryopump for Test Example 1. Figure 4 This is a graph showing the rate of change of the cryopump pumping speed for Test Example 1. Figure 5 This is a graph showing the temporal change in the pressure of the chamber in Experimental Example 2. Figure 6 This is a graph showing the temporal change in the pumping speed of the cryopump for Test Example 2. Figure 7 This is a graph showing the temporal change in the rate of change of the cryopump pumping speed for Test Example 2. Figure 8 This is a system configuration diagram showing a low-temperature system according to a second embodiment. DETAILED DESCRIPTION

[0014] [First embodiment] Reference Figure 1 , describing a first embodiment of a low-temperature system and a vacuum processing method. [Low Temperature System] like Figure 1 As shown, the cryogenic system 1 includes a cryopump 10 and a control unit 20 . The cryopump 10 includes a heat shield 11 , a cryogenic panel 12 , a baffle 13 , and a refrigerator 14 .

[0015] The heat shield 11 is cylindrical and has an opening 11A at one end. The low-temperature panel 12 is housed in the heat shield 11. The baffle 13 is located at the opening 11A of the heat shield 11. The refrigerator 14 is configured to cool the heat shield 11 and the low-temperature panel 12.

[0016] The height of the heat shield 11 is a first height H11. Within the area defined by the heat shield 11 and the baffle 13, the area from the opening 11A of the heat shield 11 to half the first height H11 (H11 / 2) is the temperature control area 10S. The portion of the heat shield 11 contained in the temperature control area 10S and at least one of the baffle 13 is a heating target portion. The cryogenic system 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 portion.

[0017] Of the pair of surfaces facing each other in the thickness direction of the baffle 13, the surface facing the low-temperature panel 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. Thus, the temperature sensor 15 is located within the temperature control area 10S.

[0018] In this embodiment, the heating unit 16 is also attached to the back surface 13R of the baffle 13. Figure 1 In the illustrated example, the cryogenic system 1 includes two heating units 16. The cryogenic system 1 only needs to include one or more heating units 16.

[0019] Baffle 13 may also be a circular, porous plate. Temperature sensor 15 may also be located in a central portion, including the center of baffle 13, as viewed from a point opposite surface 13F of baffle 13. Two heating units 16 may also be arranged along the diameter of baffle 13, sandwiching temperature sensor 15 between them. This can suppress variations in the degree of heating within the surface of baffle 13 and reduce the reflection of the local temperature of baffle 13 in the detection value of temperature sensor 15. Furthermore, the distances between each heating unit 16 and temperature sensor 15 are preferably equal.

[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 reaches 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 detection value output by the temperature sensor 15. Based on the detection value of the temperature sensor 15, the control unit 20 generates a control signal for controlling the driving of the heating unit 16. 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. It also includes memory such as an SSD and an HDD. It also includes memory such as a ROM, RAM, and register memory. The control unit 20 may also include an integrated circuit such as an ASIC or an FPGA. All processing performed by the control unit 20 may be performed by software included in the control unit 20 or by a combination of integrated circuits and software included in the control unit 20.

[0023] A cryopump 10 is connected to a chamber C included in a vacuum processing apparatus. The cryopump 10 is driven to evacuate the interior of the chamber C. Furthermore, the cryopump 10 cannot evacuate the pressure within the chamber C from atmospheric pressure. Therefore, after a roughing pump (not shown) connected to the chamber C evacuates the interior of the chamber C to a pressure below atmospheric pressure, the cryopump 10 evacuates the interior of the chamber C.

[0024] In the cryopump 10, the baffle 13 has an inlet for the process gas exhausted from the chamber C connected to the cryopump 10. Therefore, when exhaust of the process gas begins, the temperature of the baffle 13 decreases before that of the thermal shield 11 and the cryo-panel 12 located within the thermal shield 11. According to the cryogenic system 1, the temperature of the baffle 13 is controlled based on a temperature detected near the baffle 13, thereby suppressing deviations in the actual temperature of the baffle 13 from a target value for the baffle 13. Consequently, since the temperature of the baffle 13, through which the process gas is introduced, is less likely to fluctuate, variations in the flow of the process gas into the thermal shield 11 can be suppressed, resulting in improved accuracy in maintaining the exhaust speed within the cryopump 10.

[0025] As described above, in this embodiment, the baffle 13 is the portion to be heated. Furthermore, because the baffle 13 is in contact with the heat shield 11, the heat applied to the baffle 13 by the heater 16 is also supplied to the heat shield 11 via the baffle 13. However, the baffle 13 is the primary component of the heat shield 11 and the baffle 13 that is heated by the heater 16. Furthermore, the temperature sensor 15 is attached to the baffle 13 to detect the temperature of the baffle 13. The heater 16 is attached to the baffle 13 to heat 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 of the temperature of the baffle 13 may be within a 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 cooling stage 14A and a second cooling stage 14B. During the operation of the refrigerator 14, the temperature of the second cooling stage 14B is lower than the temperature of the first cooling stage 14A. The temperature of the first cooling stage 14A may be, for example, from 50K to 110K. The temperature of the second cooling stage 14B may be, for example, from 10K to 20K. The refrigerator 14 includes a first cylinder 14C and a second cylinder 14D. The first cylinder 14C is connected to the first cooling stage 14A. The second cylinder 14D is connected to the first cooling stage 14A and the second cooling stage 14B.

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

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

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

[0031] [Vacuum treatment method] The vacuum processing method uses a cryopump 10 connected to a chamber C supplying process gases to exhaust the process gases from the chamber C. In the vacuum processing method disclosed herein, the temperature within the temperature control region 10S is detected, and the heating target portion 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 within the temperature control region 10S, and the baffle 13 is the heating target portion.

[0032] In a vacuum processing apparatus equipped with a cryopump 10, the temperature of the baffle 13 may become unstable while processing multiple process objects. During this period of unstable temperature of the baffle 13, the pumping speed of the cryopump 10 also becomes unstable. In the vacuum processing method, the temperature of the baffle 13 may be regulated at the start of process gas supply. Specifically, the temperature within the temperature regulation region 10S is detected, and the heating target portion is heated so that the temperature of the baffle 13 reaches a predetermined value.

[0033] For example, the temperature adjustment of the baffle 13 may be started at the start of process gas supply, or it may be started a predetermined time before the start of process gas supply. This allows the temperature of the baffle 13, and consequently the pumping speed of the cryopump 10, to be stably maintained from the start of process gas supply. Furthermore, from the perspective of maintaining the temperature of the baffle 13 with higher accuracy, it is preferable to start the temperature adjustment of the baffle 13 a predetermined time before the start of process gas supply.

[0034] Furthermore, when processing of the processing object in the vacuum processing apparatus is interrupted, the temperature of the baffle 13 may change during the interruption relative to the processing. Therefore, the temperature adjustment of the baffle 13 may be continued during the interruption of processing. Alternatively, the temperature adjustment of the baffle 13 may be resumed after a predetermined period, for example, an interruption of one hour or more, has elapsed.

[0035] Furthermore, from the viewpoint of suppressing power consumption in the vacuum processing apparatus, it is preferable to stop the temperature adjustment of the baffle 13 while the supply of the process gas is stopped.

[0036] [Test Example] Reference Figures 2 to 7 A test example of the low-temperature system 1 will be described. [Test Example 1] A cryopump 10 was used. It had a temperature sensor 15 and two heaters 16 attached to the baffle 13. The temperature of the baffle 13 was controlled by a controller 20 using the value detected by the temperature sensor 15 to maintain it at 100K. Argon was used as the process gas. A test dome, gas inlet, and connecting piping were used in accordance with JIS B 8329-1:2015, "Vacuum Technology - Performance Test Methods of Vacuum Pumps - Part 1: General Test Methods."

[0037] [Test Example 2] In Test Example 1, the temperature of the baffle 13 was adjusted to be maintained at 100K in the same manner as in Test Example 1, except that the heating unit 16 was replaced with a heating unit attached to the first cooling stage 14A to heat the first cooling stage 14A.

[0038] [Evaluation results] In Experiment 1, the pressure (Pa) of chamber C was measured as follows: Figure 2 As shown in FIG. 1 , the results of measuring the exhaust speed (L / sec) of the cryopump 10 are as follows: Figure 3 As shown, in addition, the rate of change of the exhaust velocity is as follows Figure 4 In contrast, in Test Example 2, the pressure of chamber C was measured as shown in Figure 5 As shown, the results of measuring the exhaust speed of the cryopump are as follows Figure 6 As shown, in addition, the rate of change of the exhaust velocity is as follows Figure 7 shown.

[0039] In both Test Examples 1 and 2, the pressure in the chamber C and the pumping speed of the cryopump 10 were measured starting from the time the cryopump 10 started to be driven. Furthermore, in both Test Examples 1 and 2, the supply of process gas to the chamber C began five minutes after the cryopump 10 started to be driven. Furthermore, the pressure in the chamber C and the pumping speed of the cryopump 10 were measured for 47 minutes after the cryopump 10 started to be driven.

[0040] like Figure 2 As shown in FIG. 1 , in Experimental Example 1, it was confirmed that the pressure in the chamber C was maintained substantially constant. Figure 3As shown in FIG. 1 , it was confirmed that the exhaust speed of the cryopump 10 was maintained substantially constant in Test Example 1. Figure 4 As shown, in Test Example 1, it was confirmed that the maximum value of the change rate of the exhaust speed of the cryopump 10 was 0%.

[0041] like Figure 5 As shown in FIG. 2 , it was confirmed that the pressure in chamber C increased from 5 minutes to 20 minutes and remained substantially constant after 20 minutes. Figure 6 As shown in FIG. 2 , it was confirmed that the exhaust speed of the cryopump decreased from 5 minutes to 20 minutes, and remained substantially constant after 20 minutes. Figure 7 As shown, in Test Example 2, it was confirmed that the maximum value of the change rate of the cryopump pumping speed was approximately 5%.

[0042] Thus, it was confirmed that the cryopump 10 including the temperature sensor 15 for measuring the temperature of the baffle 13 and the heater 16 for heating the baffle 13 could suppress changes in the pumping speed of the cryopump 10 and changes in the pressure of the chamber C. The temperature control of the baffle 13 in Test Example 1 was less likely to cause a delay in the cooling of the baffle 13 than in Test Example 2, and thus the temperature of the baffle 13 could be maintained more stably.

[0043] As described above, according to the first embodiment of the cryogenic system and the vacuum processing method, the following effects can be obtained. (1-1) Since the temperature of the baffle 13 is controlled based on the temperature detected near the baffle 13, it is possible to suppress deviations in the actual temperature of the baffle 13 from the target value of the baffle 13. As a result, since the temperature of the baffle 13, through which the process gas is introduced, is less likely to fluctuate, variations in the flow of the process gas into the thermal shield 11 can be suppressed. As a result, the accuracy with which the pumping speed of the cryopump 10 is maintained can be improved.

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

[0045] (1-3) When the predetermined value is not less than 60 K and not more than 130 K, the effectiveness of stabilizing the pumping speed of the cryopump 10 can be improved.

[0046] [Second embodiment] Reference Figure 8A second embodiment of a cryogenic system and vacuum processing method will be described. The second embodiment differs from the first embodiment in its structure related to heating the baffle. Therefore, these differences will be described in detail below. In the first embodiment, components identical to those in the second embodiment will be assigned the same reference numerals as in the first embodiment, and detailed descriptions of these components will be omitted.

[0047] [Low Temperature System] like Figure 8 As shown, the cryogenic system 1 of this embodiment does not include the heating unit 16 included in the cryogenic system 1 of the first embodiment. The refrigerator 14 of the cryopump 30 includes an inverter 31 electrically connected to the 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 based on the detection 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 control the operating frequency, or in other words, the rotational speed, of the motor 14M. The inverter 31 converts the power input to the motor 14M into power corresponding to a 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] By increasing the operating frequency of motor 14M, the frequency of the heat cycle in refrigerator 14 is increased. As a result, first cooling stage 14A is cooled, and the temperature of heat shield 11 connected to first cooling stage 14A decreases. Conversely, by decreasing the operating frequency of motor 14M, the frequency of the heat cycle in refrigerator 14 is also decreased. As a result, the temperature of first cooling stage 14A increases, and the temperature of heat shield 11 connected to first cooling stage 14A increases.

[0051] In the cryogenic system 1 of this embodiment, the portion of the thermal shield 11 contained within the temperature control region 10S is the heated portion. Furthermore, because the thermal shield 11 is in contact with the baffle 13, the heat applied to the thermal shield 11 by the first cooling stage 14A is also supplied to the baffle 13 via the thermal shield 11. However, the primary components of the thermal shield 11 and the baffle 13 heated by the first cooling stage 14A are the thermal shield 11.

[0052] As with the cryogenic system 1 of the first embodiment, a temperature sensor 15 is attached to the baffle 13 to detect the temperature of the baffle 13. The refrigerator 14 is a heating unit that heats the heating target portion. Based on the detected temperature value of the baffle 13, the refrigerator 14 included in the cryopump 30 is used to heat the baffle 13 via the thermal shield 11. Therefore, without providing a heating unit for heating the baffle 13, the temperature of the baffle 13 can be controlled with high precision.

[0053] As with the cryogenic system 1 of the first embodiment, it is preferable to perform temperature adjustment 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] Furthermore, the flow rate of the gas in contact with the first cooling stage 14A is lower than the flow rate of the gas in contact with the baffle 13. Therefore, even if the temperature of the first cooling stage 14A is controlled to a temperature sufficient to maintain the temperature of the baffle 13 at a predetermined value, the temperature of the first cooling 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 the first cooling stage 14A exceeds a predetermined value, the temperature adjustment using the baffle 13 of the refrigerator 14 may be switched to a control for maintaining the temperature of the first cooling stage 14A at the predetermined value. In this case, control for maintaining the temperature of the first cooling stage 14A at the predetermined value may be performed based on the detected temperature value of the first cooling stage 14A.

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

[0057] As described above, according to the second embodiment of the cryogenic system and the 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 value of the baffle 13, the baffle 13 is heated via the heat shield 11 using the refrigerator 14 included in the cryopump 30. This allows the temperature of the baffle 13 to be controlled with high precision without providing a heating unit for heating the baffle 13.

[0058] The above-mentioned embodiments may be implemented in the following modified forms. [Temperature sensor] The location where the temperature sensor 15 is mounted is not limited to the back surface 13R of the baffle 13. The temperature sensor 15 only needs to be arranged within the temperature adjustment region 10S.

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

[0060] [Combination of Embodiments] The structure of the first embodiment may be combined with the structure of the second embodiment. That is, the cryogenic system 1 of the second embodiment may also include a heater 16 attached to the baffle 13. In this case, heating of the baffle 13 by the heater 16 and heating of the baffle 13 by the refrigerator 14 may be switched during the supply of process gas.

[0061] For example, the baffle 13 may be heated using the heating unit 16 during a predetermined period after the start of process gas supply, and then heated using the refrigerator 14 after the predetermined period. In this case, the baffle 13 can be more responsively controlled during the period when the baffle 13 is easily cooled by exhaust of the process gas, making it easier to stably maintain the temperature of the baffle 13.

[0062] Alternatively, the period in which the temperature of the baffle 13 is adjusted may include a period in which both the heating of the baffle 13 by the heating unit 16 and the heating of the baffle 13 by the refrigerator 14 are performed. Description of Reference Numerals

[0063] 1: Low temperature system 10: Cryogenic pump 11: Heat shield 12: Low temperature panel 13: Baffle 14: Refrigerator 15: Temperature sensor 16: Heating unit 20: Control Department C: Chamber

Claims

1. A cryogenic system comprising a cryogenic pump, wherein the cryogenic pump comprises: a heat shield in the shape of a cylinder with an opening at one end; a low-temperature panel housed in the heat shield; a baffle located at the opening of the heat shield; and A refrigerator configured to cool the heat shield and the low-temperature panel. The height of the heat shield is the first height, The area defined by the heat shield and the baffle, which extends from the opening of the heat shield to half of the first height, is a temperature control area. At least one of the portion of the heat shield included in the temperature adjustment area and the baffle is a heating target portion. The cryogenic system comprises: A temperature sensor is located in the temperature adjustment area; a heating portion that heats the heating target portion; and a control unit for controlling 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.

2. The cryogenic system according to claim 1, wherein: The heating target portion is the baffle, The temperature sensor is installed on the baffle to detect the temperature of the baffle. The heating unit is mounted on the baffle to heat the baffle.

3. The cryogenic system according to claim 1, wherein: The heating target portion is a portion of the heat shield included in the temperature adjustment region. The temperature sensor is installed on the baffle to detect the temperature of the baffle. The refrigerator is the heating unit.

4. The cryogenic system according to any one of claims 1 to 3, wherein: The predetermined value is within the range of 60K to 130K.

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

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