Cryopump system, cryopump monitoring method and cryopump monitoring program

Abstract

To provide a cryopump monitoring technique useful in easily grasping the state of a cryopump system.SOLUTION: A cryopump system 100 comprises: a sensor which measures a measurement parameter associated with the cryopump system 100; a cryopump controller 110 which is configured to receive the measurement parameter from the sensor, determine an operation parameter of the cryopump system 100 so that the measurement parameter follows up a target value, and operate the cryopump system 100 with the determined operation parameter; and a cryopump monitor 130 which is configured to acquire time-series data on the measurement parameter and time-series data on the operation parameter, and then display a time-series graph of the measurement parameter and a time-series graph of the operation parameter on the same time base.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a cryopump system, a cryopump monitoring method, and a cryopump monitoring program. [Background technology]

[0002] A cryopump is a vacuum pump that captures gas molecules by condensation or adsorption on cryopanels cooled to extremely low temperatures and then exhausts them. Cryopumps are installed in vacuum process equipment to realize the clean vacuum environment required for semiconductor circuit manufacturing processes and other processes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 7-293438 Summary of the Invention [Problem to be solved by the invention]

[0004] During operation of a cryopump, various data are continuously acquired from the cryopump. The acquired data may include, for example, the cooling temperature of the cryopanel in the cryopump and the radiation shield surrounding it, the internal pressure of the refrigerator that cools the cryopump, and the operating frequency of the motor that drives the refrigerator. Often, multiple cryopumps are installed in one vacuum process device, and such data is acquired for each cryopump. This large amount of diverse data on the cryopump can be used for monitoring and diagnosing the cryopump.

[0005] Cryopump design engineers are sometimes required to organize and analyze large amounts of acquired data to understand the cryopump's condition in order to verify that the diagnostic results are accurate and, if necessary, to report such verification to the cryopump user. In reality, such work is performed by engineers using their own know-how, but it is time-consuming. In addition, it is practically difficult for users who do not have such know-how to perform it themselves.

[0006] It is an exemplary object of an embodiment of the present invention to provide a cryopump monitoring technique that is useful for easily understanding the state of a cryopump system. [Means for solving the problem]

[0007] According to one aspect of the present invention, a cryopump system includes a sensor that measures measurement parameters related to the cryopump system, a cryopump controller configured to receive the measurement parameters from the sensor, determine operating parameters of the cryopump system so as to cause the measured parameters to track target values, and operate the cryopump system with the determined operating parameters, and a cryopump monitor configured to acquire time series data of the measured parameters and time series data of the operating parameters, and display a time series graph of the measured parameters and a time series graph of the operating parameters with the time axes aligned.

[0008] According to one aspect of the present invention, a cryopump monitoring method comprises acquiring time series data of measured parameters related to a cryopump system, acquiring time series data of operating parameters of the cryopump system that is controlled to cause the measured parameters to track target values, and displaying a time series graph of the measured parameters and a time series graph of the operating parameters with the time axes aligned.

[0009] Any combination of the above components, and any transformation of the present invention into a method, device, system, recording medium, computer program, etc., are also effective as aspects of the present invention. Effect of the Invention

[0010] According to the present invention, a cryopump monitoring technique can be provided that is useful for easily understanding the state of a cryopump system. [Brief description of the drawings]

[0011] [Figure 1] 1 is a schematic diagram showing a cryopump system according to an embodiment; [Diagram 2] 1 is a schematic diagram showing an example of a cryopump that can be used in a cryopump system according to an embodiment. FIG. [Diagram 3] FIG. 2 is a schematic diagram showing an example of a compressor that can be used in the cryopump system according to the embodiment. [Figure 4] 4 is a flowchart showing a cryopump monitoring method according to the embodiment. [Diagram 5] 2 is a schematic diagram showing an example of a cryopump monitor that can be used in the cryopump system according to the embodiment. FIG. [Figure 6] 4 is a schematic diagram showing an example of a time series graph display in a cryopump monitor according to an embodiment; FIG. [Figure 7] 13 is a schematic diagram showing another example of a time series graph display in the cryopump monitor according to the embodiment. FIG. [Figure 8] 13 is a schematic diagram showing another example of a time series graph display in the cryopump monitor according to the embodiment. FIG. [Figure 9] FIG. 4 is a schematic diagram showing another example of a cryopump system according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, the embodiments for carrying out the present invention will be described in detail with reference to the drawings. In the description and drawings, the same or equivalent components, members, and processes are given the same reference numerals, and duplicated descriptions are omitted as appropriate. The scale and shape of each part shown in the drawings are set for convenience in order to facilitate the description, and are not to be interpreted as being limiting unless otherwise specified. The embodiments are merely examples, and do not limit the scope of the present invention in any way. All features and combinations thereof described in the embodiments are not necessarily essential to the invention.

[0013] 1 is a schematic diagram showing a cryopump system 100 according to an embodiment. The cryopump system 100 is mounted on a vacuum process apparatus 200 and is used to evacuate a vacuum vessel 202 of the vacuum process apparatus 200 to a desired vacuum level. The vacuum process apparatus 200 is configured to process a workpiece, such as a wafer, by a desired vacuum process in a vacuum environment within the vacuum vessel 202. The vacuum process apparatus 200 may be, for example, an ion implantation apparatus, a sputtering apparatus, a deposition apparatus, or any other vacuum process apparatus.

[0014] In addition to the vacuum vessel 202, the vacuum processing apparatus 200 includes a host controller 204 and a housing 206. The host controller 204 is configured to control communication between the vacuum processing apparatus 200 and the cryopump system 100. The host controller 204 may be configured as or form part of a controller that controls the vacuum processing apparatus 200. The housing 206 forms an exterior of the vacuum processing apparatus 200 and houses various components of the vacuum processing apparatus 200. The vacuum vessel 202 and the host controller 204 are disposed within the housing 206.

[0015] The housing 206 may be an enclosure that covers the entire surface of the vacuum process apparatus 200. The housing 206 may include a frame structure in which components of the vacuum process apparatus 200 are arranged and supported, a panel member that separates the inside of the vacuum process apparatus 200 from the outside, and an openable and closable door for accessing the inside of the vacuum process apparatus 200 from the outside. The panel member and the door may be attached to the frame structure. The housing 206 may have a radiation shielding material, such as lead, to prevent radiation that may be generated in the vacuum process apparatus 200 from leaking out.

[0016] Alternatively, the housing 206 does not have to cover the entire surface of the vacuum process apparatus 200. For example, a part of the housing 206 may be open so that a part of the vacuum process apparatus 200 can be seen from the outside.

[0017] The cryopump system 100 includes at least one cryopump 10, at least one compressor 12, a cryopump controller 110, a network 120, and a cryopump monitor 130.

[0018] The cryopump 10 is attached to a vacuum vessel 202 of a vacuum process apparatus 200 in order to evacuate the vacuum vessel 202. Thus, the cryopump 10 is disposed in a housing 206 of the vacuum process apparatus 200 together with the vacuum vessel 202. An exemplary configuration of the cryopump 10 that can be used in the cryopump system 100 according to the embodiment will be described later with reference to FIG.

[0019] The compressor 12 is provided to supply and discharge refrigerant gas to and from an expander (described later) provided in the cryopump 10. The compressor 12 is connected to the expander of the cryopump 10 by a gas line 13, and is disposed outside the housing 206 of the vacuum process apparatus 200. The gas line 13 includes a high-pressure line 13a that connects the compressor 12 to the expander so as to supply refrigerant gas from the compressor 12 to the expander, and a low-pressure line 13b that connects the compressor 12 to the expander so as to recover refrigerant gas from the expander to the compressor 12. An exemplary configuration of the compressor 12 that can be used in the cryopump system 100 according to the embodiment will be described later with reference to FIG. 3.

[0020] The cryopump system 100 may be provided with a plurality of cryopumps 10, for example, several to a dozen or more cryopumps 10. The cryopump system 100 may also be provided with a plurality of compressors 12 for supplying and discharging refrigerant gas to and from these cryopumps 10.

[0021] The cryopump controller 110 is configured to comprehensively control the cryopump system 100 based on commands received from the host controller 204. The cryopump controller 110 is also configured to transmit information related to the cryopump system 100 to the host controller 204. Thus, the cryopump controller 110 can control the cryopump 10 and the compressor 12 based on commands from the host controller 204, and can transmit information related to the cryopump 10 and information related to the compressor 12 to the host controller 204.

[0022] The cryopump controller 110 is communicatively connected to the host controller 204 by a first communication line 208. The first communication line 208 may be a communication cable such as RS-232C. As an example, the cryopump controller 110 is disposed in the housing 206 of the vacuum process apparatus 200, similar to the host controller 204. As another example, the cryopump controller 110 may be disposed in the housing 206 of the vacuum process apparatus 200.

[0023] As will be described in detail later, the cryopump system 100 includes sensors that measure measurement parameters related to the cryopump system 100. The cryopump system 100 may be provided with multiple sensors that each measure different measurement parameters (e.g., a first temperature sensor 22 and a second temperature sensor 23 provided in the cryopump 10, a first pressure sensor 54 and a second pressure sensor 55 provided in the compressor 12, etc.). When the cryopump system 100 includes multiple cryopumps 10, such multiple sensors may be provided for each cryopump 10.

[0024] The cryopump controller 110 may be configured to receive the measured parameters from the sensors, determine the operating parameters of the cryopump system 100 (e.g., the operating frequency of the expander motor 30) so as to cause the measured parameters to track target values, and operate the cryopump 10 with the determined operating parameters. When the cryopump system 100 includes a plurality of cryopumps 10, the cryopump controller 110 may be configured to receive the measured parameters for each of the plurality of cryopumps 10 from the sensors of the cryopump 10, determine the operating parameters of the cryopump 10 so as to cause the measured parameters to track target values, and operate the cryopump 10 with the determined operating parameters.

[0025] The network 120 communicatively connects the cryopump 10 and the cryopump controller 110. The cryopump system 100 transmits information about the cryopump 10 between the cryopump 10 and the cryopump controller 110 via the network 120. The cryopump 10 is connected to the cryopump controller 110 by a second communication line 122. The second communication line 122 may be, for example, a communication cable such as RS-485.

[0026] The network 120 further communicatively connects the compressor 12 and the cryopump controller 110. The cryopump system 100 transmits information about the compressor 12 between the compressor 12 and the cryopump controller 110 via the network 120. The compressor 12 is connected to the cryopump controller 110 by a third communication line 123. The third communication line 123 may be a communication cable such as RS-485.

[0027] The cryopump monitor 130 is connected to the network 120 and configured to display information about the cryopump 10 that is transmitted over the network 120. Additionally or alternatively, the cryopump monitor 130 may be configured to display information about the compressor 12 that is transmitted over the network 120.

[0028] As shown, the cryopump monitor 130 may be connected to the network 120 without going through the host controller 204. In other words, the cryopump monitor 130 may be configured not to communicate with the host controller 204 of the vacuum process apparatus 200. In the example shown, the cryopump monitor 130 is connected to the cryopump controller 110 by a fourth communication line 124. The fourth communication line 124 may be, for example, a communication cable such as RS-485.

[0029] The cryopump monitor 130 is disposed outside the housing 206 of the vacuum process apparatus 200. The cryopump monitor 130 may be disposed at a location remote from the housing 206. As shown in the figure, the cryopump monitor 130 may be installed on the compressor 12 or in its vicinity. The cryopump monitor 130 may be installed on a monitor installation surface provided in the vicinity of the compressor 12. The monitor installation surface may be, for example, a wall surface in the vicinity of the compressor 12 or a surface of equipment in the vicinity of the compressor 12.

[0030] The cryopump monitor 130 may be removably installed in the cryopump system 100, and may be connected to the network 120 as necessary when monitoring the cryopump system 100. It is not essential that the cryopump monitor 130 is permanently installed in the cryopump system 100. For example, the cryopump monitor 130 may be removably attached to the compressor 12.

[0031] In this embodiment, the cryopump monitor 130 is configured to acquire time series data of the measurement parameters and time series data of the operation parameters, and display a time series graph of the measurement parameters and a time series graph of the operation parameters with the time axes aligned. An exemplary configuration of the cryopump monitor 130 that can be used in the cryopump system 100 according to the embodiment will be described later with reference to FIG.

[0032] The internal configurations of the cryopump controller 110 and the cryopump monitor 130 are realized as hardware configurations by elements and circuits including a computer CPU and memory, and as software configurations by computer programs, etc., but are depicted in the figures as functional blocks realized by the cooperation of these. Those skilled in the art will understand that these functional blocks can be realized in various forms by combining hardware and software. For example, the cryopump monitor 130 can be implemented as a combination of a processor 132 such as a CPU (Central Processing Unit) or a microcomputer, and a software program executed by the processor 132. The software program may be a computer program (e.g., a cryopump monitoring program) for causing the processor 132 to execute the cryopump monitoring method according to the embodiment.

[0033] 2 is a schematic diagram showing an example of a cryopump 10 that can be used in a cryopump system 100 according to an embodiment. The cryopump 10 includes an expander 14, a cryopump housing 16, a radiation shield 18, and a cryopanel 20. The cryopump 10 also includes a pressure sensor 21, a rough valve 24, a purge valve 26, and a vent valve 28, which are installed in the cryopump housing 16.

[0034] The compressor 12 is configured to recover the refrigerant gas from the expander 14, increase the pressure of the recovered refrigerant gas, and supply the refrigerant gas to the expander 14 again. The expander 14 is also called a cold head, and constitutes a cryogenic refrigerator together with the compressor 12. The expander 14 may also be called a "refrigerator". The circulation of the refrigerant gas between the compressor 12 and the expander 14 is performed with a combination of appropriate pressure fluctuations and volume fluctuations of the refrigerant gas in the expander 14, thereby forming a thermodynamic cycle that generates cold, and the expander 14 can provide cryogenic cooling. The refrigerant gas is typically helium gas, but other suitable gases may be used. For ease of understanding, the flow direction of the refrigerant gas is indicated by arrows in FIG. 1. As an example, the cryogenic refrigerator is a two-stage Gifford-McMahon (GM) refrigerator, but it may also be a pulse tube refrigerator, a Stirling refrigerator, or other types of cryogenic refrigerator.

[0035] The cryopump vessel 16 is a vacuum vessel designed to maintain a vacuum during the evacuation operation of the cryopump 10 and to withstand the pressure of the surrounding environment (e.g., atmospheric pressure). The cryopump vessel 16 has a cryopanel housing part 16a having an intake port 17, and a refrigerator housing part 16b. The cryopanel housing part 16a has a dome-like shape with the intake port 17 open and the opposite side closed, and houses a radiation shield 18 and a cryopanel 20 inside. The refrigerator housing part 16b has a cylindrical shape, one end of which is fixed to the room temperature part of the expander 14 and the other end is connected to the cryopanel housing part 16a, and the expander 14 is inserted inside. In addition, a pressure sensor 21 measures the pressure inside the cryopump vessel 16.

[0036] The radiation shield 18 is thermally coupled to the first cooling stage of the expander 14 and is cooled to a first cooling temperature (e.g., 80K to 120K). The cryopanel 20 is thermally coupled to the second cooling stage of the expander 14 and is cooled to a second cooling temperature (e.g., 10K to 20K) lower than the first cooling temperature. The radiation shield 18 is disposed in the cryopump vessel 16 so as to surround the cryopanel 20 and blocks heat input from the cryopump vessel 16 and the surrounding environment to the cryopanel 20. Gas entering from the intake port 17 of the cryopump 10 is captured by condensation or adsorption on the cryopanel 20. The configuration of the cryopump 10, such as the arrangement and shape of the radiation shield 18 and the cryopanel 20, can be appropriately selected from various known configurations and will not be described in detail here.

[0037] Also provided within the cryopump housing 16 are a first temperature sensor 22 for measuring the temperature of the radiation shield 18 and a second temperature sensor 23 for measuring the temperature of the cryopanel 20. The cryopump controller 110 may be connected to the first temperature sensor 22 to receive a first measured temperature signal representing a first cooling temperature measured by the first temperature sensor 22, and may be connected to the second temperature sensor 23 to receive a second measured temperature signal representing a second cooling temperature measured by the second temperature sensor 23.

[0038] The rough valve 24 is attached to the cryopump vessel 16, for example, to the refrigerator housing portion 16b. The rough valve 24 is connected to a rough pump (not shown) installed outside the cryopump 10. The rough pump is a vacuum pump for evacuating the cryopump 10 to its operation start pressure. When the rough valve 24 is opened under the control of the cryopump controller 110, the cryopump vessel 16 is connected to the rough pump, and when the rough valve 24 is closed, the cryopump vessel 16 is isolated from the rough pump. The pressure in the cryopump 10 can be reduced by opening the rough valve 24 and operating the rough pump.

[0039] The purge valve 26 is attached to the cryopump vessel 16, for example, the cryopanel housing portion 16a. The purge valve 26 is connected to a purge gas supply device (not shown) installed outside the cryopump 10. When the purge valve 26 is opened under the control of the cryopump controller 110, purge gas is supplied to the cryopump vessel 16, and when the purge valve 26 is closed, the supply of purge gas to the cryopump vessel 16 is cut off. The purge gas may be, for example, nitrogen gas or other dry gas, and the temperature of the purge gas may be adjusted to, for example, room temperature or heated to a temperature higher than room temperature. The cryopump 10 can be pressurized by opening the purge valve 26 and introducing the purge gas into the cryopump vessel 16. The cryopump 10 can also be heated from an extremely low temperature to room temperature or higher.

[0040] The vent valve 28 is attached to the cryopump vessel 16, for example, to the refrigerator housing portion 16b. The vent valve 28 is provided to discharge fluid from inside the cryopump 10 to the outside. The fluid discharged from the vent valve 28 is basically gas, but may be liquid or a gas-liquid mixture. The vent valve 28 can be opened and closed under the control of the cryopump controller 110. In addition, the vent valve 28 can be mechanically opened by the pressure difference between the inside and outside of the cryopump vessel 16. The vent valve 28 is configured to also function as a safety valve for releasing excessive pressure to the outside when the pressure occurs inside the cryopump vessel 16.

[0041] The expander 14 is also provided with a variable speed expander motor 30 that drives the expander 14. The expander motor 30 has an inverter, and the operation frequency (i.e., rotation speed) of the expander motor 30 can be changed under the control of the cryopump controller 110. The operation frequency of the expander motor 30 determines the number of heat cycles (GM cycles in the case of a GM refrigerator) performed in the expander 14 per unit time, that is, the frequency of the heat cycle.

[0042] The cryopump 10 may include an input / output circuit 32 that aggregates transmission and reception between the cryopump 10 and the cryopump controller 110. The input / output circuit 32 may be, for example, an I / O module or a remote I / O unit. The input / output circuit 32 is electrically connected to each device of the cryopump 10, such as the pressure sensor 21, the first temperature sensor 22, the second temperature sensor 23, the rough valve 24, the purge valve 26, the vent valve 28, and the expander motor 30, so as to transmit and receive signals to and from these devices. The input / output circuit 32 is also communicatively connected to the cryopump controller 110 via a second communication line 122.

[0043] Therefore, the cryopump 10 transmits a measured pressure signal indicating the pressure measured in the cryopump container 16 by the pressure sensor 21 to the cryopump controller 110 via the input / output circuit 32 (and the second communication line 122). The cryopump 10 transmits measured temperature signals indicating the temperatures measured by the first temperature sensor 22 and the second temperature sensor 23 to the cryopump controller 110 via the input / output circuit 32. The cryopump 10 also transmits valve state signals indicating the open / closed state of each valve (i.e., the rough valve 24, the purge valve 26, and the vent valve 28) to the cryopump controller 110 via the input / output circuit 32. The cryopump 10 transmits a motor state signal indicating the on / off state and operating frequency of the expander motor 30 to the cryopump controller 110 via the input / output circuit 32.

[0044] Furthermore, the cryopump 10 receives valve control signals from the cryopump controller 110 indicating operation commands for each valve at the input / output circuit 32, and the input / output circuit 32 transmits these valve control signals to the corresponding valves. The valves that receive the valve control signals are opened and closed in accordance with the valve control signals. Similarly, the cryopump 10 receives motor control signals from the cryopump controller 110 indicating operation commands for the expander motor 30 at the input / output circuit 32, and the input / output circuit 32 transmits these motor control signals to the expander motor 30. The expander motor 30 is turned on and off, or its operating frequency is controlled in accordance with the motor control signal.

[0045] As described above, the cryopump controller 110 may be configured to receive measured parameters from a sensor, determine operating parameters of the cryopump 10 to cause the measured parameters to track target values, and operate the cryopump 10 with the determined operating parameters.

[0046] For example, the cryopump controller 110 may be configured to control the expander 14 based on a first cooling temperature measured by the first temperature sensor 22 during the evacuation operation of the vacuum vessel 202 by the cryopump 10. For example, the cryopump controller 110 may control the operating frequency of the expander motor 30 by feedback control so as to minimize the deviation between the first measured temperature and a first target temperature. The cryopump controller 110 may determine the operating frequency of the expander motor 30 as a function of the deviation between the measured temperature and the target temperature (e.g., by PID control). The cryopump controller 110 outputs the determined operating frequency to the expander motor 30, and the expander motor 30 is operated at the determined operating frequency.

[0047] The first target temperature is usually set to a constant value. For example, the first target temperature is determined as a specification according to a process performed in the vacuum process apparatus 200 to which the cryopump 10 is attached. Note that the target temperature may be changed as necessary during operation of the cryopump 10.

[0048] When the thermal load on the cryopump 10 increases, the temperature of the radiation shield 18 may increase. When the temperature measured by the first temperature sensor 22 is higher than the target temperature, the cryopump controller 110 increases the operating frequency of the expander motor 30. As a result, the frequency of the thermal cycle in the expander 14 is also increased, and the radiation shield 18 is cooled toward the target temperature. Conversely, when the temperature measured by the first temperature sensor 22 is lower than the target temperature, the operating frequency of the expander motor 30 is decreased, and the radiation shield 18 is heated toward the target temperature. In this way, the first cooling temperature can be kept within a temperature range near the first target temperature. Since the operating frequency of the expander motor 30 can be appropriately adjusted according to the thermal load, such control helps reduce the power consumption of the cryopump 10.

[0049] In order to adjust the cooling capacity of the expander 14, instead of or in addition to controlling the operating frequency of the expander motor 30, the expander 14 may include a heating device 34, such as an electric heater, thermally coupled to the radiation shield 18 so as to heat the radiation shield 18. The cryopump controller 110 may be configured to switch the heating device 34 on and off and / or control the power input to the heating device 34. In this case, the cryopump controller 110 may control the input to the heating device 34 by feedback control so as to minimize the deviation between the first measured temperature and the first target temperature. The cryopump controller 110 may determine the input to the heating device 34 as a function of the deviation between the measured temperature and the target temperature (e.g., by PID control). If the temperature measured by the first temperature sensor 22 is higher than the target temperature, the cryopump controller 110 reduces the input to the heating device 34 (or turns off the heating device 34). The radiation shield 18 is thereby cooled toward the target temperature. Conversely, if the temperature measured by the first temperature sensor 22 is lower than the target temperature, the input to the heating device 34 is increased (or the heating device 34 is turned on) and the radiation shield 18 is heated toward the target temperature.

[0050] Controlling the cryopump 10 in this manner according to the first target temperature is sometimes referred to as "one-stage temperature control." In one-stage temperature control, the temperature of the cryopanel 20 is not directly controlled. In other words, as a result of one-stage temperature control, the cryopanel 20 is cooled to a temperature determined by the two-stage refrigeration capacity of the expander 14 and the heat load from the outside.

[0051] Similarly, the cryopump controller 110 can also execute so-called "two-stage temperature control" in which the temperature of the cryopanel 20 is controlled by the expander 14 according to a target temperature. In this case, the cryopump controller 110 may be configured to control the expander 14 based on a second cooling temperature measured by the second temperature sensor 23. For example, the cryopump controller 110 may control the operating frequency of the expander motor 30 (or the input to a heating device that heats the cryopanel 20) by feedback control so as to minimize the deviation between the second measured temperature and the second target temperature. This allows the temperature of the cryopanel 20 to follow the target temperature. In the two-stage temperature control, the first-stage cooling temperature (i.e., the temperature of the radiation shield 18) is not directly controlled. In the two-stage temperature control, the first-stage cooling temperature is determined by the first-stage refrigeration capacity of the expander 14 and the heat load from the outside.

[0052] In addition, during regeneration operation of the cryopump 10, the cryopump controller 110 may control the rough valve 24, the purge valve 26, the vent valve 28, and the expander motor 30 based on the pressure within the cryopump vessel 16 (or, if necessary, based on the temperature of the cryopanel 20 and the pressure within the cryopump vessel 16).

[0053] 3 is a schematic diagram showing an example of a compressor 12 that can be used in a cryopump system 100 according to an embodiment. The compressor 12 includes a high-pressure gas outlet 50, a low-pressure gas inlet 51, a high-pressure flow path 52, a low-pressure flow path 53, a first pressure sensor 54, a second pressure sensor 55, a bypass line 56, a compressor main body 57, and a compressor housing 58.

[0054] The high-pressure gas outlet 50 is installed in the compressor housing 58 as a working gas discharge port of the compressor 12, and the low-pressure gas inlet 51 is installed in the compressor housing 58 as a working gas suction port of the compressor 12. The high-pressure line 13a is connected to the high-pressure gas outlet 50, and the low-pressure line 13b is connected to the low-pressure gas inlet 51. The high-pressure flow path 52 connects the discharge port of the compressor body 57 to the high-pressure gas outlet 50, and the low-pressure flow path 53 connects the low-pressure gas inlet 51 to the suction port of the compressor body 57. The compressor housing 58 accommodates the high-pressure flow path 52, the low-pressure flow path 53, the first pressure sensor 54, the second pressure sensor 55, the bypass line 56, and the compressor body 57. The compressor 12 is also called a compressor unit.

[0055] The compressor body 57 is configured to compress the working gas sucked from its suction port and discharge it from its discharge port. The compressor body 57 may be, for example, a scroll type, a rotary type, or other pump that pressurizes the working gas. The compressor body 57 may include a variable speed compressor motor 57a. The compressor motor 57a has an inverter, and the motor operation frequency can be changed under the control of the cryopump controller 110. In this way, the compressor body 57 may be configured to vary the flow rate of the working gas discharged. Alternatively, the compressor body 57 may be configured to discharge a fixed constant flow rate of the working gas. The compressor body 57 may also be called a compression capsule.

[0056] The first pressure sensor 54 is disposed in the high-pressure passage 52 to measure the pressure of the working gas flowing through the high-pressure passage 52. The second pressure sensor 55 is disposed in the low-pressure passage 53 to measure the pressure of the working gas flowing through the low-pressure passage 53. Therefore, the first pressure sensor 54 and the second pressure sensor 55 can also be called a high-pressure sensor and a low-pressure sensor, respectively.

[0057] The bypass line 56 connects the high pressure flow path 52 to the low pressure flow path 53 so as to return the working gas from the high pressure flow path 52 to the low pressure flow path 53 by bypassing the expander 14. The bypass line 56 is provided with a relief valve 60 for opening and closing the bypass line 56 or for controlling the flow rate of the working gas flowing through the bypass line 56. The relief valve 60 is configured to open when a differential pressure equal to or greater than a set pressure acts between its inlet and outlet. The relief valve 60 may be an on-off valve or a flow rate control valve, and may be, for example, a solenoid valve. The set pressure can be appropriately set based on the designer's empirical knowledge or on experiments, simulations, etc. performed by the designer. This makes it possible to prevent the differential pressure between the high pressure line 13a and the low pressure line 13b from exceeding the set pressure and becoming excessive.

[0058] As an example, the relief valve 60 may be opened and closed under the control of the cryopump controller 110. The cryopump controller 110 may compare the measured differential pressure between the high pressure line 13a and the low pressure line 13b with a set pressure, and control the relief valve 60 to open the relief valve 60 when the measured differential pressure is equal to or greater than the set pressure, and close the relief valve 60 when the measured differential pressure is less than the set pressure. The cryopump controller 110 may obtain the measured differential pressure between the high pressure line 13a and the low pressure line 13b from the measured pressures of the first pressure sensor 54 and the second pressure sensor 55. As another example, the relief valve 60 may be configured to operate as a so-called safety valve, i.e., may be mechanically opened when a differential pressure equal to or greater than the set pressure acts between the inlet and outlet.

[0059] The cryopump controller 110 may be configured to receive the measured parameters from the sensors, determine the operating parameters of the compressor 12 so as to make the measured parameters follow the target values, and operate the compressor 12 with the determined operating parameters. For example, the cryopump controller 110 may be configured to control the operating frequency of the compressor motor 57a based on the measured pressure (e.g., the first pressure measured by the first pressure sensor 54, or the second pressure measured by the second pressure sensor 55, or the differential pressure between the first pressure and the second pressure). The cryopump controller 110 may control the operating frequency of the compressor motor 57a by feedback control so as to minimize the deviation between the measured pressure and the target pressure. The cryopump controller 110 may determine the operating frequency of the compressor motor 57a as a function of the deviation between the measured pressure and the target pressure (e.g., by PID control). The cryopump controller 110 outputs the determined operating frequency to the compressor motor 57a, and the compressor motor 57a will be operated at the determined operating frequency.

[0060] The compressor 12 may have various other components. For example, the high-pressure flow path 52 may be provided with an oil separator, an adsorber, etc. The low-pressure flow path 53 may be provided with a storage tank and other components. The compressor 12 may also be provided with an oil circulation system that cools the compressor body 57 with oil, a cooling system that cools the oil with cooling water, etc.

[0061] The operation of the cryopump 10 having the above configuration will be described below. When the cryopump 10 is operated, the vacuum vessel 202 is first rough-evacuated to a predetermined pressure (for example, about 100 Pa or about 10 Pa) by another appropriate rough-evacuation pump. A gate valve is usually installed between the vacuum vessel 202 and the intake port 17 of the cryopump 10, and this gate valve is closed during rough evacuation of the vacuum vessel 202. Then (or in parallel with rough evacuation of the vacuum vessel 202), the cryopump 10 is operated. The radiation shield 18 and the cryopanel 20 are cooled to a first cooling temperature and a second cooling temperature, respectively, by driving the expander 14. A baffle thermally coupled to the radiation shield 18 may be provided at the intake port 17, and this baffle is also cooled to the first cooling temperature together with the radiation shield 18. Then, the gate valve is opened, and evacuation of the vacuum vessel 202 by the cryopump 10 is started.

[0062] The baffle and radiation shield 18 cooled to the first cooling temperature cool the gas flying from the vacuum vessel 202 toward the cryopump 10. These surfaces have a sufficiently low vapor pressure (for example, 10 -8 A gas (pressure below 1 Pa) condenses. This gas may be referred to as a first type gas. The first type gas is, for example, water vapor. In this manner, the cryopump 10 can pump out the first type gas. A portion of the gas whose vapor pressure is not sufficiently low at the first cooling temperature enters the cryopump 10 from the intake port 17. Alternatively, another portion of the gas is reflected by the baffle and returns to the vacuum vessel 202 without entering the cryopump 10.

[0063] The gas that has entered the cryopump 10 is cooled by the cryopanel 20. The surface of the cryopanel 20 is provided with a gas having a sufficiently low vapor pressure (for example, 10 -8 A gas (pressure of 0.1 Pa or less) is condensed. This gas may be referred to as a second gas. The second gas is, for example, argon. In this manner, the cryopump 10 can pump the second gas.

[0064] The gas whose vapor pressure is not sufficiently low at the second cooling temperature is adsorbed by an adsorbent such as activated carbon provided on the surface of the cryopanel 20. This gas may be referred to as a third gas. The third gas is, for example, hydrogen. In this manner, the cryopump 10 can pump the third gas. Thus, the cryopump 10 can pump various gases by condensation or adsorption, and can make the vacuum level of the vacuum vessel 202 reach a desired level.

[0065] 4 is a flowchart showing a cryopump monitoring method according to an embodiment. This method includes acquiring time series data of measurement parameters related to the cryopump system 100 (S10), acquiring time series data of operation parameters of the cryopump system 100 that is controlled so that the measurement parameters follow target values ​​(S20), and displaying a time series graph of the measurement parameters and a time series graph of the operation parameters with the same time axis (S30).

[0066] As described above, the cryopump system 100 is provided with various sensors for measuring measurement parameters related to the cryopump system 100, such as the first temperature sensor 22, the second temperature sensor 23, the first pressure sensor 54, and the second pressure sensor 55. The measurement parameters continuously measured by these sensors during operation of the cryopump system 100 are input to the cryopump controller 110 for control of the cryopump system 100. The cryopump controller 110 determines the operating parameters of the cryopump system 100 based on the acquired measurement parameters.

[0067] The time series data of the measurement parameters and the operating parameters thus obtained may be stored in a storage unit provided in the cryopump controller 110. Alternatively, the time series data of the measurement parameters and the time series data of the operating parameters may be stored in an external storage device connectable to the cryopump controller 110. These time series data may be relatively long-term data, for example, time series data covering an operating period of at least one month, at least six months, or at least one year.

[0068] In S10, the processor 132 (see FIG. 1) of the cryopump monitor 130 acquires time-series data of the measurement parameters from the cryopump controller 110. The processor 132 may acquire the time-series data of the measurement parameters from an external storage device in which the data is stored.

[0069] The processor 132 may acquire time series data for a plurality of measurement parameters. For example, the processor 132 may acquire time series data for each of the first to fourth measurement parameters. The first measurement parameter may be a first cooling temperature measured by the first temperature sensor 22. The second measurement parameter may be a second cooling temperature measured by the second temperature sensor 23. The third measurement parameter may be a first pressure measured by the first pressure sensor 54. The fourth measurement parameter may be a second pressure measured by the second pressure sensor 55.

[0070] In S20, the processor 132 acquires time series data of the operating parameters from the cryopump controller 110 (or an external storage device). The processor 132 may acquire time series data for a plurality of operating parameters, for example, time series data for the operating frequency of the expander motor 30 and the operating frequency of the compressor motor 57a. When the expander 14 is provided with a heating device 34, the processor 132 may acquire time series data of the input to the heating device 34 instead of or in addition to the operating frequency of the expander motor 30.

[0071] In S30, the processor 132 generates a time series graph of the measurement parameter based on the acquired time series data of the measurement parameter. When the time series data of a plurality of measurement parameters is acquired, the processor 132 generates a time series graph for each measurement parameter. Furthermore, the processor 132 generates a time series graph of the operation parameter based on the acquired time series data of the operation parameter. When the time series data of a plurality of operation parameters is acquired, the processor 132 generates a time series graph for each operation parameter. The time series graph is a graph in which one of the vertical and horizontal axes (e.g., the horizontal axis) represents time, and the other (e.g., the vertical axis) represents the measurement parameter (or operation parameter).

[0072] 5, the cryopump monitor 130 includes a display 134 that displays information about the cryopump system 100. The processor 132 is configured to control the display 134 to display a time series graph of at least one measured parameter and / or operating parameter that has been generated.

[0073] For example, the processor 132 may be configured to set a display area on the display 134 to display a particular time series graph. A single display area may be set on the display 134, and a time series graph of one measured parameter (or operating parameter) may be displayed in this display area. Alternatively, multiple display areas may be set on the display 134, each displaying a corresponding time series graph, and each display area may display a corresponding time series graph. For example, a first display area and a second display area may be set on the display 134, and a time series graph of the measured parameter may be displayed in the first display area, and a time series graph of the operating parameter may be displayed in the second display area.

[0074] The processor 132 may be configured to switch between a plurality of graph display screens on the display 134. In this case, for example, at least one display area may be set in the first graph display screen, and at least one display area may be set in the second graph display screen. Time series graphs of different measurement parameters (or operating parameters) may be displayed in the display area of ​​the first graph display screen and the display area of ​​the second graph display screen. For example, the first graph display screen may display time series graphs of measurement parameters and operating parameters related to the cryopump 10, and the second graph display screen may display time series graphs of measurement parameters and operating parameters related to the compressor 12.

[0075] The processor 132 may also be configured to display multiple time series graphs together in a specific display area. For example, the same measurement parameter (e.g., first cooling temperature) for multiple cryopumps 10 may be displayed together in a specific display area. Also, the same operating parameter (e.g., operating frequency of the expander motor 30) for multiple cryopumps 10 may be displayed together in a specific display area.

[0076] In this embodiment, the processor 132 is configured to display a time series graph of the measured parameter and a time series graph of the operating parameter on the same time axis on the display 134. Examples of such graph displays are described below.

[0077] 5 is a schematic diagram showing an example of a cryopump monitor 130 that can be used in the cryopump system 100 according to the embodiment. As shown in the figure, a first display area 136a, a second display area 136b, and a third display area 136c are set on a display 134 of the cryopump monitor 130, as an example.

[0078] In this example, the first display area 136a displays a time series graph of the first cooling temperature T1 measured by the first temperature sensor 22 as the first measurement parameter. In this first time series graph, the vertical axis represents the first cooling temperature T1, and the horizontal axis represents time. In the second display area 136b, the operating frequency of the expander motor 30 is displayed as the first operating parameter. In the second time series graph, the vertical axis represents the operating frequency of the expander motor 30, and the horizontal axis represents time. In the third display area 136c, a time series graph of the second cooling temperature T2 measured by the second temperature sensor 23 is displayed as the second measurement parameter. In the third time series graph, the vertical axis represents the second cooling temperature T2, and the horizontal axis represents time.

[0079] These display areas, specifically, the first display area 136a, the second display area 136b, and the third display area 136c, are set to be aligned vertically on the display 134. Therefore, the horizontal axes, i.e., the time axes, of the time series graphs displayed in these display areas are aligned. In other words, the same position on the horizontal axis of the time series graphs displayed in each display area represents the same point in time.

[0080] The first display area 136a, the second display area 136b, and the third display area 136c are set at the top, middle, and bottom of the display 134, respectively. The second display area 136b is adjacent to the bottom of the first display area 136a, and the third display area 136c is adjacent to the bottom of the second display area 136b. Therefore, a time series graph of the operating frequency of the expansion machine motor 30 is displayed adjacent to the bottom of the time series graph of the first cooling temperature T1. Furthermore, a time series graph of the second cooling temperature T2 is displayed adjacent to the bottom of these two time series graphs.

[0081] The multiple display areas are set so that the time series graphs displayed in each display area can be distinguished from one another. In FIG. 5, as an example, the first display area 136a, the second display area 136b, and the third display area 136c are set on the display 134 so as to be vertically aligned with a small gap between them. As another example, two adjacent display areas (for example, the first display area 136a and the second display area 136) may be set so as to be aligned without a gap. Alternatively, the two display areas may be set so as to at least partially overlap. In short, as long as the time series graphs of different parameters can be distinguished on the display 134, the display areas for those time series graphs may be separated from one another or may overlap on the display 134.

[0082] As described later, the time series graph of the first measured parameter and the time series graph of the first operating parameter may be displayed side by side so that the target value of the first measured parameter and the limit value of the first operating parameter are close to each other. To achieve this, the display position of the target value of the first measured parameter may be determined on an edge (e.g., a lower edge) of the first display area 136a, and the display position of the limit value of the first operating parameter may be determined on an edge of the second display area 136b that is close to the edge of the first display area 136a (e.g., an upper edge of the second display area 136b).

[0083] Fig. 6 is a schematic diagram showing an example of a time series graph display in the cryopump monitor 130 according to the embodiment. In this graph display, as described with reference to Fig. 5, the first cooling temperature T1 is displayed in the first display area 136a, the operating frequency of the expander motor 30 is displayed in the second display area 136b, and the second cooling temperature T2 is displayed in the third display area 136c.

[0084] In this example, the vertical axis of the first display area 136a is set to the right side of this area, and a numerical value (80K, 90K, 100K) indicating the first cooling temperature T1 is displayed to the right. The vertical axis of the second display area 136b is set to the left side of this area, and a numerical value (50Hz to 100Hz) indicating the operating frequency of the expansion motor 30 is displayed to the left. Similarly, the vertical axis of the third display area 136c is set to the left side of this area, and a numerical value (10K to 20K) indicating the second cooling temperature T2 is displayed to the left.

[0085] 6, the bottom edge of the first display area 136a and the top edge of the second display area 136b are in contact with each other, so the horizontal line indicating 80K in the first display area 136a and the horizontal line indicating 100Hz in the second display area 136b are aligned. Meanwhile, the bottom edge of the second display area 136b and the top edge of the third display area 136c are separated from each other, so the horizontal line indicating 50Hz in the second display area 136b and the horizontal line indicating 20K in the third display area 136c are drawn separately.

[0086] In this embodiment, as shown in FIG. 6, the cryopump monitor 130 can display time series graphs of the first cooling temperature T1, the operating frequency of the expander motor 30, and the second cooling temperature T2, all aligned on the time axis.

[0087] Therefore, it is possible to visually and integrally read the measured parameters and the operating parameters determined based thereon, such as the first cooling temperature T1 and the operating frequency of the expander motor 30. The state of the cryopump system, for example, the behavior of the measured parameters and the operating parameters at a certain point in time or over a certain time range, can be easily grasped.

[0088] Furthermore, for different measurement parameters, such as the first cooling temperature T1 and the second cooling temperature T2, the behaviors of these parameters can be understood on the same time axis.

[0089] In this example, the cryopump system 100 has four cryopumps (Pump 1, Pump 2, Pump 3, Pump 4). Therefore, in FIG. 6, four time series graphs are displayed for each of the first cooling temperature T1, the operating frequency of the expander motor 30, and the second cooling temperature T2 corresponding to the four cryopumps (i.e., a total of 12 graphs are displayed). The four graphs for the first cooling temperature T1 are displayed together in the first display area 136a, the four graphs for the operating frequency of the expander motor 30 are displayed together in the second display area 136b, and the four graphs for the second cooling temperature T2 are displayed together in the third display area 136c. Therefore, it is easy to compare the measurement parameters (or operating parameters) between different cryopumps 10.

[0090] However, for the first cooling temperature T1, the four graphs overlap in most parts. This is because the one-stage temperature control described above is being performed. The first cooling temperature T1 in each of the four cryopumps is controlled so that it matches the target temperature (80K in this example) within a specified temperature range (for example, ±0.1°C).

[0091] However, as can be seen in the areas surrounded by dashed squares 138a, 138b, and 138c in FIG. 6, a situation may occur in which the first cooling temperature T1 of a certain cryopump 10 deviates from the target temperature and exceeds the target temperature. Such a situation may occur when the heat load on the cryopump 10 from the outside, such as the vacuum vessel 202, is excessively large, or due to deterioration over time caused by long-term operation of the cryopump 10. At this time, in order to return the first cooling temperature T1 to the target temperature, the operating frequency of the expansion motor 30 is increased, and finally reaches a predetermined upper limit value (95 Hz in this example) and is maintained at this upper limit value. Nevertheless, it can be seen from FIG. 6 that the first cooling temperature T1 continues to rise.

[0092] In this example, as shown in Fig. 6, a time series graph of the first cooling temperature T1 and a time series graph of the operating frequency of the expander motor 30 are displayed side by side so that the target value of the first cooling temperature T1 (e.g., 80K) and the limit value of the operating frequency of the expander motor 30 (e.g., an upper limit, e.g., 95Hz) are close to each other. Specifically, the display position of the target value of the first cooling temperature T1 is determined at the lower edge of the first display area 136a, and the display position of the upper limit value of the operating frequency of the expander motor 30 is determined at the upper edge of the second display area 136b. This allows the viewer to continuously and integrally recognize the behavior of the cryopump system 100, that is, when the operating frequency of the expander motor 30 reaches the upper limit, the first cooling temperature T1 rises beyond the target temperature.

[0093] The processor 132 of the cryopump monitor 130 may be configured to display on the display 134 a mark 140 indicating that a diagnosis of the cryopump 10 has been performed, at a position 142 of the diagnosis time on the time axis of the time series graph. In this manner, the presence of related diagnosis results can be easily ascertained on the time series graph of the measurement parameters and / or operating parameters.

[0094] The diagnosis may be performed by the cryopump controller 110 based on the acquired measurement parameters and / or operating parameters. The diagnosis may be based on a comparison between the acquired parameters and a diagnostic threshold value, or may be based on a known cryopump diagnostic method that has already been proposed, or may be based on any other suitable diagnostic method, which will not be described in detail herein.

[0095] In the illustrated example, a symbol "!" is displayed as the mark 140, pointing to a position 142 on the time axis corresponding to the diagnosis time. Note that the mark 140 may include characters representing the diagnosis result, such as "failure", "abnormality", or "normal".

[0096] Furthermore, the mark 140 may be displayed so as to indicate a parameter that requires attention in the diagnosis result. In the illustrated example, at the diagnosis time point indicated by the mark 140, the operating frequency of the expansion motor 30 reaches an upper limit value, and as a result, the first cooling temperature T1 begins to deviate from the target temperature, so the mark 140 includes an arrow indicating the position of the diagnosis time point on the time series graph of the first cooling temperature T1.

[0097] The processor 132 may also be configured to display the diagnostic information of the cryopump 10 linked to the mark 140 on the display 134 in response to the operator's designation of the mark 140. The diagnostic information of the cryopump 10 may be a diagnostic report including documents, charts, photographs, etc. explaining the diagnostic results. If the cryopump 10 is disassembled for diagnosis, photographs and explanatory documents of the disassembly may be included in the diagnostic information. The diagnostic information of the cryopump 10 may be linked to the mark 140, for example, in a hypertext format or other suitable format. The mark 140 can be designated by an appropriate input operation by the operator, such as by operating a pointer displayed on the display 134. This is convenient because it allows the detailed diagnostic results to be easily understood.

[0098] 7 is a schematic diagram showing another example of a time series graph display in the cryopump monitor 130 according to the embodiment. When the heating device 34 is controlled instead of controlling the operating frequency of the expansion motor 30, the input to the heating device 34 may be displayed in the second display area 136b. As in the above example, the first display area 136a and the third display area 136c display the first cooling temperature T1 and the second cooling temperature T2, respectively. Three time series graphs of the first cooling temperature T1, the input to the heating device 34, and the second cooling temperature T2 are displayed on the display 134 with the time axes aligned.

[0099] As described with reference to Fig. 6, a situation may occur in which the first cooling temperature T1 of the cryopump 10 deviates from the target temperature and exceeds the target temperature (dashed squares 138a, 138b, 138c in Fig. 6). At this time, in order to return the first cooling temperature T1 to the target temperature, the input to the heating device 34 is reduced, and finally reaches a predetermined lower limit value (0 W in this example) and is maintained at this lower limit value. In short, the heating device 34 is turned off. However, it can be seen from Fig. 7 that the first cooling temperature T1 continues to rise even when the heating device 34 is off.

[0100] A time series graph of the first cooling temperature T1 and a time series graph of the input to the heating device 34 are displayed side by side so that the target value of the first cooling temperature T1 (e.g., 80K) and the limit value of the input to the heating device 34 (e.g., a lower limit, e.g., 0 W) are close to each other. Specifically, the display position of the target value of the first cooling temperature T1 is determined at the lower edge of the first display area 136a, and the display position of the lower limit value of the input to the heating device 34 is determined at the upper edge of the second display area 136b. The vertical axis of the second display area 136b representing the input to the heating device 34 has smaller values ​​as it goes up. This allows the viewer to continuously and integrally recognize the behavior of the cryopump system 100, in which the first cooling temperature T1 rises beyond the target temperature when the input to the heating device 34 reaches the lower limit.

[0101] In addition, when both the operating frequency of the expander motor 30 and the input to the heating device 34 are controlled to control the first cooling temperature T1 to a target temperature, time series graphs of both the operating frequency of the expander motor 30 and the input to the heating device 34 may be displayed together with a time series graph of the first cooling temperature T1.

[0102] FIG. 8 is a schematic diagram showing another example of a time series graph display in the cryopump monitor 130 according to the embodiment. The cryopump monitor 130 may display the measurement parameters and operation parameters related to the compressor 12 with the time axis aligned. Therefore, the cryopump monitor 130 may set a fourth display area 136d and a fifth display area 136e on the display 134. The fourth display area 136d displays a time series graph of the first pressure PH measured by the first pressure sensor 54 and the second pressure PL measured by the second pressure sensor 55 together. The fifth display area 136e displays a time series graph of the differential pressure DP between the first pressure PH and the second pressure PL and a time series graph of the operation frequency F of the compressor motor 57a together. In other words, the fifth display area 136e in which the differential pressure DP is displayed and the sixth display area in which the operation frequency F is displayed are set on the display 134 so as to overlap each other. Measured and operating parameters relating to the compressor 12 may also be displayed as indicia 140 .

[0103] These two display areas shown in FIG. 8 may be set on the same screen as the first to third display areas (136a to 136c) related to the cryopump 10, or may be set on separate, switchable screens.

[0104] As indicated by mark 140 in FIG. 8, even if the operating frequency F of the compressor motor 57a reaches a predetermined upper limit value (78 Hz in this example) during operation of the compressor 12, the pressure difference DP between the first pressure PH and the second pressure PL may deviate from the target pressure difference (e.g., 1.5 MPa) and fall below this target pressure difference (note that the vertical axis on the right side showing the pressure difference DP in the fifth display area 136e indicates smaller values ​​as it goes up).

[0105] 8, a time series graph of the differential pressure DP and a time series graph of the operating frequency of the compressor motor 57a are displayed side by side so that the target value of the differential pressure DP (e.g., 1.5 MPa) and the limit value of the operating frequency of the compressor motor 57a (e.g., an upper limit, e.g., 78 Hz) are close to each other. This allows the viewer to continuously and integrally recognize the behavior of the cryopump system 100, that is, when the operating frequency of the compressor motor 57a reaches the upper limit, the differential pressure DP deviates from the target value and decreases.

[0106] The present invention has been described above based on examples. It will be understood by those skilled in the art that the present invention is not limited to the above-described embodiments, that various design changes are possible, that various modifications are possible, and that such modifications are also within the scope of the present invention. Various features described in relation to one embodiment can also be applied to other embodiments. A new embodiment resulting from a combination has the combined effects of each of the combined embodiments.

[0107] In the above embodiment, the cryopump monitor 130 displays the time series graph as an image on the display 134, but the cryopump monitor 130 may be configured to display in other formats. For example, the cryopump monitor 130 may be configured to display the time series graph on paper by printing.

[0108] Furthermore, the cryopump monitor 130 may be located remotely from the cryopump 10 and the vacuum process apparatus 200 and communicatively connected to the cryopump controller 110, for example, via the Internet or any other suitable communication network. The cryopump controller 110 may output time-series data of the measurement parameters and / or operation parameters to the communication network, and the cryopump monitor 130 may receive the data output from the cryopump controller 110 from the communication network.

[0109] The cryopump monitor 130 may be a stand-alone device. In other words, the cryopump monitor 130 may be configured not to communicate with the cryopump controller 110. In this case, the cryopump monitor 130 may acquire such time-series data of the measurement parameters and / or operation parameters from a computer-readable medium in which such time-series data is stored. The computer-readable medium may have the time-series data output in advance from the cryopump controller 110 (or another controller or storage device) and stored therein. Such a computer-readable medium may be connected to the cryopump monitor 130, and the time-series data may be read into the cryopump monitor 130. The computer-readable medium may be any of various known forms of computer-readable media, such as a hard disk, a USB memory, or the like.

[0110] The cryopump monitor 130 may be a computer (e.g., a general-purpose computer such as a personal computer) in which a cryopump monitoring program according to the embodiment is implemented. Alternatively, the cryopump monitor 130 may be implemented in an electronic device that an operator can carry, such as a smartphone. Alternatively, the cryopump monitor 130 may be implemented in a monitor device mounted on the vacuum process apparatus 200.

[0111] In the above embodiment, the case where a plurality of cryopumps 10 are controlled by a common cryopump controller 110 has been described as an example, but the present invention is not limited thereto. As shown in FIG. 9, the cryopump system 100 may include a plurality of controllers 110a for individually controlling the plurality of cryopumps 10, instead of the cryopump controller 110. As described above, each cryopump 10 may be provided with sensors for measuring measurement parameters related to the cryopump 10 (for example, as shown in FIGS. 2 and 3, a first temperature sensor 22 and a second temperature sensor 23 provided in the cryopump 10, a first pressure sensor 54 and a second pressure sensor 55 provided in the compressor 12, etc.). Each controller 110a may be configured to receive measurement parameters for the corresponding cryopump 10 from the sensor of the cryopump 10, determine operation parameters of the cryopump 10 so as to make the measurement parameters follow target values, and operate the cryopump 10 with the determined operation parameters.

[0112] The cryopump monitor 130 may be configured to acquire time series data of the measurement parameters and time series data of the operation parameters for each of the multiple cryopumps 10, and display the time series graphs of the measurement parameters and the time series graphs of the operation parameters with the time axes aligned. In this case, the cryopump monitor 130 may acquire the time series data of the measurement parameters and / or the operation parameters from each controller 110a via a communication network. Alternatively, the cryopump monitor 130 may acquire such time series data from a computer-readable medium in which the time series data of the measurement parameters and / or the operation parameters is stored. In this manner, as illustrated in FIG. 6, the cryopump monitor 130 may display time series graphs of the first cooling temperature T1, the operation frequency of the expansion motor 30, and the second cooling temperature T2.

[0113] In the above embodiment, the compressor 12 is controlled by the cryopump controller 110, but the present invention is not limited to this. The cryopump system 100 may include a compressor controller 12a that controls the compressor 12, as shown in FIG. 9. The compressor controller 12a may be configured to control the compressor 12 autonomously (i.e., independently of the control of the cryopump 10). Thus, the compressor controller 12a may be configured to receive measurement parameters related to the compressor 12 from a sensor, determine operation parameters of the compressor 12 so as to make the measurement parameters follow target values, and operate the compressor 12 with the determined operation parameters. For example, the compressor controller 12a may be configured to control the operation frequency of the compressor motor 57a based on a measured pressure (e.g., a first pressure measured by the first pressure sensor 54, or a second pressure measured by the second pressure sensor 55, or a differential pressure between the first pressure and the second pressure). The compressor controller 12a may be provided separately from the cryopump controller 110 and mounted on the compressor 12. The cryopump system 100 illustrated with reference to Figures 1 to 3 may also be provided with a compressor controller 12a that controls the compressor 12 in this manner.

[0114] The cryopump monitor 130 may be configured to acquire time series data of the measurement parameters and time series data of the operation parameters of the compressor 12, and display the time series graph of the measurement parameters and the time series graph of the operation parameters with the same time axis. In this case, the cryopump monitor 130 may acquire the time series data of the measurement parameters and / or the operation parameters from the compressor controller 12a via a communication network. Alternatively, the cryopump monitor 130 may acquire such time series data from a computer-readable medium in which the time series data of the measurement parameters and / or the operation parameters is stored. In this manner, as illustrated in FIG. 8, the cryopump monitor 130 may display time series graphs of the first pressure PH measured by the first pressure sensor 54, the second pressure PL measured by the second pressure sensor 55, the differential pressure DP between the first pressure PH and the second pressure PL, and the operation frequency F of the compressor motor 57a.

[0115] The embodiments of the present invention can be expressed as follows, with each of the numbered items:

[0116] 1. A sensor for measuring a measurement parameter related to a cryopump system; a cryopump controller configured to receive the measurement parameters from the sensor, determine operating parameters of the cryopump system so as to cause the measurement parameters to track target values, and operate the cryopump system with the determined operating parameters; A cryopump system comprising: a cryopump monitor configured to acquire time series data of the measured parameters and time series data of the operating parameters, and display a time series graph of the measured parameters and a time series graph of the operating parameters with the time axes aligned.

[0117] 2. The cryopump system described in item 1, characterized in that the cryopump monitor is configured to display a time series graph of the measured parameter and a time series graph of the operating parameter side by side so that the target value of the measured parameter and the limit value of the operating parameter are close to each other.

[0118] 3. The cryopump system described in item 2, characterized in that the cryopump monitor is configured to determine the display position of the target value of the measured parameter at the edge of a first display area that displays a time series graph of the measured parameter, and to determine the display position of the limit value of the operating parameter at an edge of a second display area that displays a time series graph of the operating parameter that is close to the edge of the first display area.

[0119] 4. A cryopump system described in any one of items 1 to 3, characterized in that the cryopump monitor is configured to display a mark indicating that a diagnosis of the cryopump system has been performed at the position of the diagnosis time on the time axis.

[0120] 5. The cryopump system of claim 4, wherein the cryopump monitor is configured to display diagnostic information of the cryopump system associated with the mark in response to an operator designating the mark.

[0121] 6. Further comprising a second sensor for measuring a second measurement parameter related to the cryopump system that is different from the measurement parameter; The cryopump system described in any one of items 1 to 5, characterized in that the cryopump monitor is configured to acquire time series data of the second measurement parameter and display a time series graph of the second measurement parameter by aligning the time axis with the time series graphs of the measurement parameter and the operating parameter.

[0122] 7. The cryopump system comprises: A plurality of cryopumps; a plurality of sensors, each of which measures a measurement parameter related to a corresponding cryopump of the plurality of cryopumps; the cryopump controller is configured to receive, for each of the plurality of cryopumps, the measurement parameters from corresponding sensors among the plurality of sensors, determine operating parameters of the cryopump so as to cause the measurement parameters to track target values, and operate the cryopump with the determined operating parameters; The cryopump system described in any one of items 1 to 6, characterized in that the cryopump monitor is configured to acquire time series data of the measurement parameters and time series data of the operating parameters for each of the multiple cryopumps, and display a time series graph of the measurement parameters and a time series graph of the operating parameters with the time axes aligned.

[0123] 8. The cryopump system described in item 7, characterized in that the cryopump monitor is configured to collectively display multiple time series graphs of the measured parameters for the multiple cryopumps, and to collectively display multiple time series graphs of the operating parameters for the multiple cryopumps.

[0124] 9. The cryopump system comprises: A plurality of cryopumps; a plurality of sensors, each of which measures a measurement parameter associated with a corresponding cryopump of the plurality of cryopumps; a plurality of controllers for individually controlling the plurality of cryopumps instead of the cryopump controller; each controller is configured to receive the measurement parameters from a corresponding one of the plurality of sensors for a corresponding cryopump among the plurality of cryopumps, determine operating parameters of the cryopump so as to cause the measurement parameters to track target values, and operate the corresponding cryopump with the determined operating parameters; The cryopump system described in any one of items 1 to 6, characterized in that the cryopump monitor is configured to acquire time series data of the measurement parameters and time series data of the operating parameters for each of the multiple cryopumps, and display a time series graph of the measurement parameters and a time series graph of the operating parameters with the time axes aligned.

[0125] 10. Acquiring time series data of measurement parameters relating to the cryopump system; acquiring time series data of an operating parameter of the cryopump system controlled so as to make the measured parameter follow a target value; and displaying the time series graph of the measurement parameters and the time series graph of the operating parameters with the same time axis.

[0126] 11. A cryopump monitoring method as described in item 10, characterized in that the displaying comprises displaying a time series graph of the measured parameter and a time series graph of the operating parameter side by side so that the target value of the measured parameter and the limit value of the operating parameter are close to each other.

[0127] 12. A cryopump monitoring method as described in item 11, characterized in that the displaying step includes determining a display position of the target value of the measured parameter at an edge of a first display area that displays a time series graph of the measured parameter, and determining a display position of the limit value of the operating parameter at an edge of a second display area that displays a time series graph of the operating parameter that is close to the edge of the first display area.

[0128] 13. A cryopump monitoring method described in any of items 10 to 12, characterized in that the displaying comprises displaying a mark indicating that a diagnosis of the cryopump system has been performed at the position of the diagnosis time on the time axis.

[0129] 14. A cryopump monitoring method as described in item 13, characterized in that the displaying comprises displaying diagnostic information of the cryopump system associated with the mark in response to an operator's designation of the mark.

[0130] 15. The method further comprises obtaining time series data of a second measurement parameter related to the cryopump system that is different from the measurement parameter; A cryopump monitoring method described in any one of items 10 to 12, characterized in that the displaying includes displaying a time series graph of the second measurement parameter with the time axis aligned with the time series graphs of the measurement parameter and the operating parameter.

[0131] 16. The cryopump system comprises a plurality of cryopumps; obtaining the time series data of the measurement parameters includes obtaining the time series data of the measurement parameters for each of the plurality of cryopumps; acquiring the time series data of the operating parameters includes acquiring, for each of the plurality of cryopumps, time series data of the operating parameters of the cryopumps that are controlled so that the measured parameters follow target values; A cryopump monitoring method described in any one of items 10 to 15, characterized in that the displaying includes displaying a time series graph of the measured parameters and a time series graph of the operating parameters with the time axes aligned for each of the multiple cryopumps.

[0132] 17. A cryopump monitoring method as described in item 16, characterized in that the displaying comprises collectively displaying multiple time series graphs of the measured parameters for the multiple cryopumps, and collectively displaying multiple time series graphs of the operating parameters for the multiple cryopumps.

[0133] 18. Acquiring time series data of measurement parameters relating to a cryopump system; acquiring time series data of an operating parameter of the cryopump system controlled so as to make the measured parameter follow a target value; and displaying a time series graph of the measurement parameters and a time series graph of the operation parameters with the same time axis.

[0134] The present invention has been described using specific terms based on the embodiments, but the embodiments merely show one aspect of the principles and applications of the present invention, and many modifications and changes in arrangement are permitted to the embodiments without departing from the spirit of the present invention as defined in the claims. [Explanation of symbols]

[0135] 10 cryopump, 100 cryopump system, 110 cryopump controller, 130 cryopump monitor, 136a first display area, 136b second display area.

Claims

1. a sensor for measuring a measurement parameter related to the cryopump system; a cryopump controller configured to receive the measurement parameters from the sensor, determine operating parameters of the cryopump system so as to cause the measurement parameters to track target values, and operate the cryopump system with the determined operating parameters; A cryopump system comprising: a cryopump monitor configured to acquire time series data of the measured parameters and time series data of the operating parameters, and display a time series graph of the measured parameters and a time series graph of the operating parameters with the time axes aligned.

2. The cryopump system of claim 1, wherein the cryopump monitor is configured to display a time series graph of the measured parameter and a time series graph of the operating parameter side by side so that the target value of the measured parameter and the limit value of the operating parameter are close to each other.

3. The cryopump system of claim 2, wherein the cryopump monitor is configured to determine a display position of the target value of the measured parameter at an edge of a first display area that displays a time series graph of the measured parameter, and to determine a display position of the limit value of the operating parameter at an edge of a second display area that displays a time series graph of the operating parameter that is close to the edge of the first display area.

4. The cryopump system described in any one of claims 1 to 3, characterized in that the cryopump monitor is configured to display a mark indicating that a diagnosis of the cryopump system has been performed at the position of the diagnosis time on the time axis.

5. The cryopump system of claim 4, wherein the cryopump monitor is configured to display diagnostic information of the cryopump system associated with the mark in response to an operator's designation of the mark.

6. a second sensor for measuring a second measurement parameter related to the cryopump system that is different from the measurement parameter; A cryopump system as described in any one of claims 1 to 3, characterized in that the cryopump monitor is configured to acquire time series data of the second measurement parameter and display a time series graph of the second measurement parameter with the time axis aligned with the time series graphs of the measurement parameter and the operating parameter.

7. The cryopump system comprises: A plurality of cryopumps; a plurality of sensors, each of which measures a measurement parameter related to a corresponding cryopump of the plurality of cryopumps; the cryopump controller is configured to receive, for each of the plurality of cryopumps, the measurement parameters from corresponding sensors among the plurality of sensors, determine operating parameters of the cryopump so as to cause the measurement parameters to track target values, and operate the cryopump with the determined operating parameters; A cryopump system as described in any one of claims 1 to 3, characterized in that the cryopump monitor is configured to acquire time series data of the measured parameters and time series data of the operating parameters for each of the multiple cryopumps, and display a time series graph of the measured parameters and a time series graph of the operating parameters with the time axes aligned.

8. The cryopump system of claim 7, wherein the cryopump monitor is configured to collectively display multiple time series graphs of the measured parameters for the multiple cryopumps and to collectively display multiple time series graphs of the operating parameters for the multiple cryopumps.

9. The cryopump system comprises: A plurality of cryopumps; a plurality of sensors, each of which measures a measurement parameter associated with a corresponding cryopump of the plurality of cryopumps; a plurality of controllers for individually controlling the plurality of cryopumps instead of the cryopump controller; each controller is configured to receive the measurement parameters from a corresponding one of the plurality of sensors for a corresponding cryopump among the plurality of cryopumps, determine operating parameters of the cryopump so as to cause the measurement parameters to track target values, and operate the corresponding cryopump with the determined operating parameters; A cryopump system as described in any one of claims 1 to 3, characterized in that the cryopump monitor is configured to acquire time series data of the measured parameters and time series data of the operating parameters for each of the multiple cryopumps, and display a time series graph of the measured parameters and a time series graph of the operating parameters with the time axes aligned.

10. Obtaining time series data of measurement parameters relating to the cryopump system; acquiring time series data of an operating parameter of the cryopump system controlled so as to make the measured parameter follow a target value; and displaying the time series graph of the measurement parameters and the time series graph of the operating parameters with the same time axis.

11. The cryopump monitoring method of claim 10, wherein the displaying comprises displaying a time series graph of the measured parameter and a time series graph of the operating parameter side by side so that the target value of the measured parameter and the limit value of the operating parameter are close to each other.

12. The cryopump monitoring method of claim 11, characterized in that the displaying comprises determining a display position of the target value of the measured parameter at an edge of a first display area displaying a time series graph of the measured parameter, and determining a display position of the limit value of the operating parameter at an edge of a second display area displaying a time series graph of the operating parameter that is close to the edge of the first display area.

13. A cryopump monitoring method as described in any one of claims 10 to 12, characterized in that the displaying comprises displaying a mark indicating that a diagnosis of the cryopump system has been performed at the diagnosis time position on the time axis.

14. The cryopump monitoring method of claim 13, wherein the displaying comprises displaying diagnostic information of the cryopump system associated with the mark in response to an operator's designation of the mark.

15. acquiring time series data of a second measurement parameter related to the cryopump system that is different from the measurement parameter; A cryopump monitoring method as described in any one of claims 10 to 12, characterized in that the displaying includes displaying a time series graph of the second measurement parameter by aligning the time axis with the time series graphs of the measurement parameter and the operating parameter.

16. Obtaining time series data of measurement parameters relating to the cryopump system; acquiring time series data of an operating parameter of the cryopump system controlled so as to make the measured parameter follow a target value; and displaying a time series graph of the measurement parameters and a time series graph of the operation parameters with the same time axis.

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