US20220163030A1

US20220163030A1 - Cryopump system and monitoring method thereof

Info

Publication number: US20220163030A1
Application number: US17/533,983
Authority: US
Inventors: Kakeru Takahashi
Original assignee: Sumitomo Heavy Industries Ltd
Current assignee: Sumitomo Heavy Industries Ltd
Priority date: 2020-11-25
Filing date: 2021-11-23
Publication date: 2022-05-26
Also published as: KR20220072740A; JP2022083523A; TW202223237A; TWI819407B; CN114542421A; JP7554648B2

Abstract

A cryopump system mounted on a vacuum process device, the cryopump system including at least one cryopump, a cryopump controller that controls the cryopump, a network that connects the cryopump to the cryopump controller and transmits information related to the cryopump between the cryopump and the cryopump controller, and a cryopump monitor that is connected to the network and displays the information related to the cryopump, which is transmitted via the network, in which the cryopump controller is disposed in a casing of the vacuum process device, and the cryopump monitor is disposed outside the casing of the vacuum process device.

Description

RELATED APPLICATIONS

The content of Japanese Patent Application No. 2020-194876, on the basis of which priority benefits are claimed in an accompanying application data sheet, is in its entirety incorporated herein by reference.

BACKGROUND

Technical Field

Certain embodiments of the present invention relate to a cryopump system and a monitoring method thereof.

Description of Related Art

A cryopump is a vacuum pump that captures gas molecules through condensation and/or adsorption on a cryopanel cooled to a cryogenic temperature and exhausts the gas molecules. The cryopump is mounted on a vacuum process device in order to realize a clean vacuum environment required for semiconductor circuit manufacturing processes.

SUMMARY

According to an aspect of the present invention, there is provided a cryopump system mounted on a vacuum process device. The cryopump system includes at least one cryopump, a cryopump controller that controls the cryopump, a network that connects the cryopump to the cryopump controller and transmits information related to the cryopump between the cryopump and the cryopump controller, and a cryopump monitor that is connected to the network and displays the information related to the cryopump, which is transmitted via the network. The cryopump controller is disposed in a casing of the vacuum process device, and the cryopump monitor is disposed outside the casing of the vacuum process device.
According to another aspect of the present invention, there is provided a method of monitoring a cryopump system mounted on a vacuum process device. The cryopump system includes at least one cryopump, a cryopump controller that is disposed in a casing of the vacuum process device and controls the cryopump, and a network that connects the cryopump to the cryopump controller and transmits information related to the cryopump between the cryopump and the cryopump controller. The method includes connecting a cryopump monitor to the network and disposing the cryopump monitor outside the casing of the vacuum process device and displaying the information related to the cryopump, which is transmitted via the network, on the cryopump monitor.
Any combination of the components described above and a combination obtained by switching the components and expressions of the present invention between methods, devices, and systems are also effective as an aspect of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view showing a cryopump system according to an embodiment.

FIG. 2 is a schematic view showing an example of a cryopump that can be used in the cryopump system according to the embodiment.

FIG. 3 is a schematic view showing an example of a compressor that can be used in the cryopump system according to the embodiment.

FIG. 4 is a schematic view showing an example of a cryopump monitor that can be used in the cryopump system according to the embodiment.

DETAILED DESCRIPTION

The present inventors have studied a cryopump system mounted on a vacuum process device and have come to recognize the following problems. It would be convenient if information related to a cryopump can be seen during the operation of the vacuum process device. Such information is particularly useful, when an abnormality occurs, in identifying a cause of the abnormality and returning to a normal state. Thus, a plan to integrally incorporate a display unit that displays information into the cryopump is conceivable. However, even in such a case, in reality, information cannot be seen during operation in many cases. This is because even when the display unit is provided, the display unit is hidden at a place that cannot be seen from the outside in most cases as the cryopump is housed in the vacuum process device. In addition, for safety reasons such as avoiding contact with dangers such as a high voltage and a high energy beam used in the vacuum process device, internal components of the vacuum process device, such as the cryopump, are required to be physically inaccessible to humans during the operation of the vacuum process device. When the operation of the vacuum process device is stopped, the display unit can be seen by approaching the cryopump, but the operation stop of the device is not desirable since the operation stop causes a decrease in productivity.
It is desirable to provide a cryopump system in which information related to the cryopump can be easily confirmed during the operation of the vacuum process device.
Hereinafter, an embodiment 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 processing will be assigned with the same reference symbols, and redundant description thereof will be omitted as appropriate. The scales and shapes of the shown parts are set for convenience in order to make the description easy to understand, and are not to be understood as limiting unless stated otherwise. The embodiment is merely an example and does not limit the scope of the present invention. All characteristics and combinations to be described in the embodiment are not necessarily essential to the invention.
FIG. 1 is a schematic view showing a cryopump system 100 according to the embodiment. The cryopump system 100 is mounted on a vacuum process device 200 and is used in order to evacuate a vacuum chamber 202 of the vacuum process device 200 to a desired degree of vacuum. The vacuum process device 200 is configured to process an object to be processed, such as a wafer, in a vacuum environment in the vacuum chamber 202 through a desired vacuum process. The vacuum process device 200 may be, for example, an ion implanter, a sputtering device, a vapor deposition device, or other vacuum process device.
The vacuum process device 200 includes a host controller 204 and a casing 206, in addition to the vacuum chamber 202. The host controller 204 is configured to control communication between the vacuum process device 200 and the cryopump system 100. The host controller 204 may be configured as a control device that controls the vacuum process device 200, or may configure a part of such a control device. The casing 206 forms the exterior of the vacuum process device 200, and houses various components of the vacuum process device 200. The vacuum chamber 202 and the host controller 204 are disposed in the casing 206.
The casing 206 may be an enclosure that covers the entire surface of the vacuum process device 200. The casing 206 may include a frame structure in which the components of the vacuum process device 200 are provided and which supports the components, a panel member which partitions the inside of the vacuum process device 200 from the outside, and a door which can be opened and closed for accessing the inside of the vacuum process device 200 from the outside. The panel member and the door may be mounted on the frame structure. The casing 206 may include a radiation shielding material such as lead in order to prevent radiation, which can be generated by the vacuum process device 200, from leaking to the outside.
Alternatively, the casing 206 may not cover the entire surface of the vacuum process device 200. A part of the casing 206 may be opened, and a part of the vacuum process device 200 may be seen from the outside.
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.
The cryopump 10 is mounted to the vacuum chamber 202 in order to evacuate the vacuum chamber 202 of the vacuum process device 200. Accordingly, the cryopump 10 is disposed in the casing 206 of the vacuum process device 200 together with the vacuum chamber 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. 2.
The compressor 12 is provided in order to supply and discharge a refrigerant gas to an expander (to be 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 casing 206 of the vacuum process device 200. The gas line 13 includes a high pressure line 13 a that connects the compressor 12 to the expander such that the refrigerant gas is supplied from the compressor 12 to the expander and a low pressure line 13 b that connects the compressor 12 to the expander such that the refrigerant gas is collected 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.
In the cryopump system 100, a plurality of cryopumps 10, for example, several to tens of cryopumps 10 or more may be provided. In addition, in order to supply and discharge the refrigerant gas to the cryopumps 10, a plurality of compressors 12 may be provided in the cryopump system 100.
The cryopump controller 110 is configured to control the cryopump system 100 in a comprehensive manner based on a command received from the host controller 204. In addition, the cryopump controller 110 is configured to transmit information related to the cryopump system 100 to the host controller 204. Accordingly, the cryopump controller 110 can control the cryopump 10 and the compressor 12 based on the command 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.
The cryopump controller 110 is connected to the host controller 204 by a first communication line 208 so as to be able to communicate therewith. The first communication line 208 may be a communication cable such as RS-232C. Similar to the host controller 204, the cryopump controller 110 is disposed in the casing 206 of the vacuum process device 200.
The internal configuration of the cryopump controller 110 is realized by an element or a circuit including a CPU and a memory of a computer as a hardware configuration and is realized by a computer program as a software configuration, but is shown in the drawings as a functional block realized in cooperation therewith. It is clear for those skilled in the art that the functional blocks can be realized in various manners in combination with hardware and software. For example, the cryopump controller 110 can be mounted in combination with a processor (hardware) such as a central processing unit (CPU) and a microcomputer and a software program executed by the processor (hardware).
The network 120 connects the cryopump 10 to the cryopump controller 110 so as to be able to communicate with each other. The cryopump system 100 transmits information related to 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 a communication cable such as RS-485.
The network 120 further connects the compressor 12 to the cryopump controller 110 so as to be able to communicate with each other. The cryopump system 100 transmits information related to 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.
The cryopump monitor 130 is connected to the network 120 and is configured to display information related to the cryopump 10, which is transmitted via the network 120. In addition thereto or instead thereof, the cryopump monitor 130 may be configured to display information related to the compressor 12 transmitted via the network 120.
The cryopump monitor 130 is connected to the network 120 without going through the host controller 204. That is, the cryopump monitor 130 is configured so as not to communicate with the host controller 204 of the vacuum process device 200. In the embodiment, the cryopump monitor 130 is connected to the cryopump controller 110 by a fourth communication line 124. The fourth communication line 124 may be a communication cable such as RS-485.
The cryopump monitor 130 is disposed outside the casing 206 of the vacuum process device 200. The cryopump monitor 130 is disposed at a place separated from the casing 206. In the embodiment, the cryopump monitor 130 is provided in the compressor 12 or in the vicinity thereof. The cryopump monitor 130 may be detachably mounted on the compressor 12. Alternatively, the cryopump monitor 130 may be provided on a monitor provision surface provided in the vicinity of the compressor 12. The monitor provision surface may be, for example, a wall surface in the vicinity of the compressor 12, or the surface of a device in the vicinity of the compressor 12. The cryopump monitor 130 may be configured as a device that can be carried by a worker.
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. 4.
FIG. 2 is a schematic view showing an example of the cryopump 10 that can be used in the cryopump system 100 according to the embodiment. The cryopump 10 includes an expander 14, a cryopump container 16, a radiation shield 18, and a cryopanel 20. In addition, the cryopump 10 includes a pressure sensor 21, a rough valve 24, a purge valve 26, and a vent valve 28, and the components are provided in the cryopump container 16.
The compressor 12 is configured to collect a refrigerant gas from the expander 14, to pressurize the collected refrigerant gas, and to supply the refrigerant gas to the expander 14 again. The expander 14 is also called a cold head, and configures a cryocooler together with the compressor 12. The expander 14 is also called a “cryocooler” in some cases. A thermodynamic cycle, through which chill is generated, is configured by performing circulation of the refrigerant gas between the compressor 12 and the expander 14 with an appropriate combination of pressure fluctuations and volume fluctuations of the refrigerant gas in the expander 14, and thereby the expander 14 can provide cryogenic temperature cooling. Although the refrigerant gas is typically a helium gas, other appropriate gases may be used. In order to facilitate understanding, a direction in which the refrigerant gas flows is shown with an arrow in FIG. 1. Although the cryocooler is, for example, a two-stage Gifford-McMahon (GM) cryocooler, the cryocooler may be a pulse tube cryocooler, a Stirling cryocooler, or other types of cryocoolers.
The cryopump container 16 is a vacuum chamber that is designed to maintain vacuum during evacuate operation of the cryopump 10 and to withstand a pressure in the ambient environment (for example, the atmospheric pressure). The cryopump container 16 includes a cryopanel accommodation unit 16 a including an intake port 17 and a cryocooler accommodation unit 16 b. The cryopanel accommodation unit 16 a has a dome shape in which the intake port 17 is opened and an opposite side thereof is closed, and the radiation shield 18 and the cryopanel 20 are accommodated therein together. The cryocooler accommodation unit 16 b has a cylindrical shape, and has one end fixed to a room temperature portion of the expander 14 and the other end connected to the cryopanel accommodation unit 16 a. The expander 14 is inserted therein. In addition, the pressure sensor 21 measures a pressure in the cryopump container 16.
The radiation shield 18 is thermally coupled to a first cooling stage of the expander 14, and is cooled to a first cooling temperature (for example, 80 K to 120 K). The cryopanel 20 is thermally coupled to a second cooling stage of the expander 14, and is cooled to a second cooling temperature (for example, 10 K to 20 K) lower than the first cooling temperature. The radiation shield 18 is disposed in the cryopump container 16 to surround the cryopanel 20, and shields against input heat from the cryopump container 16 and the ambient environment to the cryopanel 20. A gas that enters from the intake port 17 of the cryopump 10 is captured through condensation or adsorption in the cryopanel 20. In addition, a first temperature sensor 22 that measures the temperature of the radiation shield 18 and a second temperature sensor 23 that measures the temperature of the cryopanel 20 are provided in the cryopump container 16. Since various known configurations can be adopted as appropriate as configurations of the cryopump 10, such as the dispositions and shapes of the radiation shield 18 and the cryopanel 20, description thereof will not be made in detail herein.
The rough valve 24 is attached to the cryopump container 16, for example, the cryocooler accommodation unit 16 b. The rough valve 24 is connected to a rough pump (not shown) provided outside the cryopump 10. The rough pump is a vacuum pump for evacuating the cryopump 10 to an operation starting pressure thereof. Through control by the cryopump controller 110, the cryopump container 16 communicates with the rough pump when the rough valve 24 is opened, and the cryopump container 16 is cut off from the rough pump when the rough valve 24 is closed. By opening the rough valve 24 and operating the rough pump, the cryopump 10 can be decompressed.
The purge valve 26 is attached to the cryopump container 16, for example, to the cryopanel accommodation unit 16 a. The purge valve 26 is connected to a purge gas supply device (not shown) provided outside the cryopump 10. Through control by the cryopump controller 110, a purge gas is supplied to the cryopump container 16 when the purge valve 26 is opened, and the purge gas supply to the cryopump container 16 is cut off when the purge valve 26 is closed. The purge gas may be, for example, a nitrogen gas or other dry gases. The temperature of the purge gas may be adjusted, for example, to the room temperature, or may be heated to a temperature higher than the room temperature. By opening the purge valve 26 and introducing the purge gas into the cryopump container 16, the cryopump 10 can be pressurized. In addition, the temperature of the cryopump 10 can be increased from a cryogenic temperature to the room temperature or a temperature higher than the room temperature.
The vent valve 28 is attached to the cryopump container 16, for example, the cryocooler accommodation unit 16 b. The vent valve 28 is provided in order to exhaust a fluid from the inside of the cryopump 10 to the outside. The fluid exhausted from the vent valve 28 is basically a gas, but may be a liquid or a mixture of a gas and a liquid. The vent valve 28 can be opened and closed through control by the cryopump controller 110. Along with this, the vent valve 28 can be mechanically opened by a differential pressure inside and outside the cryopump container 16. When an excessive pressure is generated in the cryopump container 16, the vent valve 28 is configured to also function as a safety valve for releasing the pressure to the outside.
In addition, the expander 14 is provided with a variable speed expander motor 30 that drives the expander 14. The expander motor 30 includes an inverter, and can change a motor operating frequency through control by the cryopump controller 110.
The cryopump controller 110 may control the expander motor 30 based on the cooling temperature of the radiation shield 18 (or the cryopanel 20) in the evacuate operation of the cryopump 10. For example, the cryopump controller 110 may control the operating frequency of the expander motor 30 such that the cooling temperature of the radiation shield 18 is constant.
In addition, in 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 a pressure in the cryopump container 16 (or if necessary, based on the temperature of the cryopanel 20 and the pressure in the cryopump container 16).
The cryopump 10 includes an input and output circuit 32 that puts transmission and reception between the cryopump 10 and the cryopump controller 110 together. The input and output circuit 32 may be, for example, an I/O module or a remote I/O unit. The input and output circuit 32 is electrically connected to each of devices 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 to transmit and receive a signal to and from each of the devices. In addition, the input and output circuit 32 is connected to the cryopump controller 110 by the second communication line 122 so as to be able to communicate therewith.
Therefore, the cryopump 10 transmits a measured pressure signal indicating a measured pressure in the cryopump container 16 from the pressure sensor 21 to the cryopump controller 110 via the input and output circuit 32 (and the second communication line 122). The cryopump 10 transmits a measured temperature signal indicating a measured temperature from each of the first temperature sensor 22 and the second temperature sensor 23 to the cryopump controller 110 via the input and output circuit 32. In addition, the cryopump 10 transmits a valve state signal indicating the open or closed state of each valve (that is, the rough valve 24, the purge valve 26, and the vent valve 28) to the cryopump controller 110 via the input and output circuit 32. The cryopump 10 transmits a motor state signal indicating the on or off state and operating frequency of the expander motor 30 to the cryopump controller 110 via the input and output circuit 32.
In addition, the cryopump 10 receives a valve control signal from the cryopump controller 110, which indicates an operation command to each valve, with the input and output circuit 32, and the input and output circuit 32 transmits the valve control signal to a corresponding valve. The valve which has received the valve control signal is opened and closed in accordance with the valve control signal. Similarly, the cryopump 10 receives a motor control signal from the cryopump controller 110, which indicates an operation command to the expander motor 30, with the input and output circuit 32, and the input and output circuit 32 transmits the motor control signal to the expander motor 30. The expander motor 30 is turned on and off or an operating frequency is controlled in accordance with the motor control signal.
In the embodiment, each cryopump 10 is not provided with a display unit such as a liquid crystal panel and a monitor that display information related to the cryopump 10, such as a measured pressure, a measured temperature, and the operation state of each valve or the expander motor 30.
FIG. 3 is a schematic view showing an example of the compressor 12 that can be used in the cryopump system 100 according to the 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 casing 58.
The high pressure gas outlet 50 is provided in the compressor casing 58 as a working gas discharge port of the compressor 12, and the low pressure gas inlet 51 is provided in the compressor casing 58 as a working gas suction port of the compressor 12. The high pressure line 13 a is connected to the high pressure gas outlet 50, and the low pressure line 13 b is connected to the low pressure gas inlet 51. The high pressure flow path 52 connects a discharge port of the compressor main body 57 to the high pressure gas outlet 50, and the low pressure flow path 53 connects the low pressure gas inlet 51 to a suction port of the compressor main body 57. The compressor casing 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 main body 57. The compressor 12 is also called a compressor unit.
The compressor main body 57 is configured to internally compress the working gas sucked from the suction port and to discharge the working gas from the discharge port. The compressor main body 57 may be, for example, a scroll type pump, a rotary type pump, or other pumps that pressurize the working gas. The compressor main body 57 may include a variable speed compressor motor 57 a. The compressor motor 57 a includes an inverter, and can change a motor operating frequency through control by the cryopump controller 110. In this manner, the compressor main body 57 may be configured to change the flow rate of the working gas to be discharged. Alternatively, the compressor main body 57 may be configured to discharge the working gas at a fixed and constant flow rate. The compressor main body 57 is called a compression capsule in some cases.
The first pressure sensor 54 is disposed in the high pressure flow path 52 to measure the pressure of the working gas flowing in the high pressure flow path 52. The second pressure sensor 55 is disposed in the low pressure flow path 53 to measure the pressure of the working gas flowing in the low pressure flow path 53. Accordingly, 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.
The bypass line 56 connects the high pressure flow path 52 to the low pressure flow path 53 such that the working gas bypasses the expander 14 and returns from the high pressure flow path 52 to the low pressure flow path 53. A relief valve 60 for opening and closing the bypass line 56 or controlling the flow rate of the working gas flowing in the bypass line 56 is provided in the bypass line 56. The relief valve 60 is configured to open when a differential pressure that is equal to or higher than a set pressure acts between an inlet and an outlet thereof. The relief valve 60 may be an on/off valve or a flow rate control valve, or may be, for example, a solenoid valve. It is possible to set the set pressure as appropriate based on empirical knowledge of a designer or experiments and simulations by the designer. Accordingly, a differential pressure between the high pressure line 13 a and the low pressure line 13 b can be prevented from exceeding the set pressure and becoming excessive.
For example, the relief valve 60 may be opened and closed under the control of the cryopump controller 110. The cryopump controller 110 may compare a measured differential pressure between the high pressure line 13 a and the low pressure line 13 b to the set pressure, and control the relief valve 60 such that the relief valve 60 is opened in a case where the measured differential pressure is equal to or higher than the set pressure, and the relief valve 60 is closed in a case where the measured differential pressure is lower than the set differential pressure. The cryopump controller 110 may acquire the measured differential pressure between the high pressure line 13 a and the low pressure line 13 b from measured pressures from 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, that is, may be mechanically opened when the differential pressure that is equal to or higher than the set pressure acts between the inlet and the outlet.
In addition, in the embodiment, the compressor 12 includes an operation panel 62 for operating the compressor 12. The operation panel 62 is provided in the compressor casing 58. The operation panel 62 is provided with an operation unit 63, a control unit 64, and a display unit 65. The operation unit 63 includes input means such as an operation button that receives the operation of the compressor 12 by an operator. The control unit 64 is housed inside the operation panel 62, and controls each of devices of the compressor 12, such as the compressor main body 57 (compressor motor 57 a) and the relief valve 60, in response to the operation of the operation unit 63. The display unit 65 is controlled by the control unit 64, and displays information related to the compressor 12.
The control unit 64 of the compressor 12 can also operate as an input and output circuit (for example, an I/O module or a remote I/O unit) that puts transmission and reception between the compressor 12 and the cryopump controller 110 together. Therefore, the control unit 64 is electrically connected to each of devices of the compressor 12, such as the first pressure sensor 54, the second pressure sensor 55, the compressor main body 57 (compressor motor 57 a), and the relief valve 60 to transmit and receive a signal to and from each of the devices. In addition, the control unit 64 is connected to the cryopump controller 110 by the third communication line 123 so as to be able to communicate therewith.
Therefore, the compressor 12 transmits a measured pressure signal indicating a measured pressure from each of the first pressure sensor 54 and the second pressure sensor 55 to the cryopump controller 110 via the control unit 64. In addition, the compressor 12 transmits a motor state signal indicating the on or off state and operating frequency of the compressor motor 57 a and a valve state signal indicating the open or closed state or opening degree of the relief valve 60 to the cryopump controller 110 via the control unit 64.
In addition, the compressor 12 receives a motor control signal from the cryopump controller 110, which indicates an operation command to the compressor motor 57 a, with the control unit 64, and the control unit 64 transmits the motor control signal to the compressor motor 57 a. The compressor motor 57 a is turned on and off or an operating frequency is controlled in accordance with the motor control signal. Similarly, the compressor 12 receives a valve control signal from the cryopump controller 110, which indicates an operation command to the relief valve 60, with the control unit 64, and the control unit 64 transmits the valve control signal to the relief valve 60. The relief valve 60 is opened and closed in accordance with the valve control signal.
The compressor 12 can include other various components. For example, an oil separator or an adsorber may be provided in the high pressure flow path 52. A storage tank and other components may be provided in the low pressure flow path 53. In addition, an oil circulation system that cools the compressor main body 57 with an oil and a cooling system that cools the oil with cooling water may be provided in the compressor 12.
FIG. 4 is a schematic view showing an example of the cryopump monitor 130 that can be used in the cryopump system 100 according to the embodiment. The cryopump monitor 130 includes an operation unit or panel 132, an input and output circuit 134, and a display unit 136.
The operation unit 132 includes input means such as various types of operation buttons for receiving an operation of the cryopump system 100 (for example, the cryopump 10 and the compressor 12) by the operator. The operation unit 132 is electrically connected to the input and output circuit 134 to transmit an operation signal indicating the operation of the operation unit 132 to the input and output circuit 134. The cryopump controller 110 receives the operation signal via the input and output circuit 134 (and the fourth communication line 124) and controls the cryopump 10 (or the compressor 12) in accordance with the operation signal. In this example, the operation unit 132 is provided in a lower portion of the cryopump monitor 130.
The input and output circuit 134 is housed inside the cryopump monitor 130 and is connected to the cryopump controller 110 by the fourth communication line 124 so as to be able to communicate therewith. The input and output circuit 134 may be, for example, an I/O module or a remote I/O unit. The fourth communication line 124 may be connected to a connector provided at the cryopump monitor 130 and be connected to the input and output circuit 134 via the connector.
The display unit 136 is electrically connected to the input and output circuit 134 to receive a signal indicating information related to the cryopump 10 and/or information related to the compressor 12 from the input and output circuit 134. The display unit 136 displays the information related to the cryopump 10 and/or the compressor 12 based on the signal received by the input and output circuit 134 from the cryopump controller 110. For example, the display unit 136 includes a display panel unit 136 a and an indicator light unit 136 b. The display panel unit 136 a may be, for example, a liquid crystal panel or other display devices that can display a number, text, a signal indicating the information related to the cryopump 10 and/or the compressor 12. The indicator light unit 136 b may be, for example, an LED lamp or other indicators that are turned on and off to indicate the information related to the cryopump 10 and/or the compressor 12. In this example, the display unit 136 is provided in an upper portion of the cryopump monitor 130.
Examples of the information related to the cryopump 10 that can be displayed on the display unit 136 include the following, and are not limited thereto.

- Current measured values from sensors mounted on the cryopump 10 (for example, the measured pressure of the pressure sensor 21, the measured temperature of the first temperature sensor 22, and the measured temperature of the second temperature sensor 23)
- Current operation states of devices mounted on the cryopump 10 (for example, the open or closed state of the rough valve 24, the open or closed state of the purge valve 26, the open or closed state of the vent valve 28, the on or off state of the expander motor 30 (that is, the on or off state of the cryopump 10), and the operating frequency of the expander motor 30)
- Operating history of the cryopump 10 (for example, the operating duration of the cryopump 10, elapsed time from regeneration start of the cryopump 10, the number of times of regeneration completion of the cryopump 10, alarm related to the cryopump 10, which is generated during the operation of the cryopump 10, communication time between the cryopump 10 and the cryopump controller 110, past measured values from sensors mounted on the cryopump 10, and past operation states of devices mounted on the cryopump 10)
- Internal parameters of the cryopump 10 (for example, set cooling temperatures of the radiation shield 18 and the cryopanel 20 for performing the evacuate operation of the cryopump 10, control parameters (for example, control gain for PID control) for adjusting the temperature of the radiation shield 18 (or the cryopanel 20), and various types of regeneration parameters that define terms and conditions such as the temperature, pressure, and opening and closing timing of each valve for performing the regeneration of the cryopump 10)
- Other parameters related to the cryopump 10 (for example, the serial number of the cryopump 10)
- Various types of commands for operating the cryopump 10

In addition, examples of information related to the compressor 12 that can be displayed on the display unit 136 include the following, and are not limited thereto.

- Current measured values from sensors mounted on the compressor 12 (for example, the measured pressure of the first pressure sensor 54, the measured pressure of the second pressure sensor 55, and a differential pressure between measured pressures from the first pressure sensor 54 and the second pressure sensor 55)
- Current operation states of devices mounted on the compressor 12 (the set valve of a differential pressure between the high pressure flow path 52 and the low pressure flow path 53, the on or off state of the compressor motor 57 a (that is, the on or off state of the compressor 12), the operating frequency of the compressor motor 57 a, the open or closed state or opening degree of the relief valve 60, and the flow rate of cooling water that cools the compressor main body 57)
- The operating history of the compressor 12 (the operating duration of the compressor 12, the use time of the adsorber, alarm related to the compressor 12, which is generated during the operation of the compressor 12, past measured values from sensors mounted on the compressor 12, and past operation states of devices mounted on the compressor 12)
- Internal parameters of the compressor 12
- Other parameters related to the compressor 12
- Various types of commands for operating the compressor 12

The cryopump monitor 130 may include a storage unit such as a large-capacity storage, or may be connectable to an external storage device. Past measured values and operation states of the cryopump system 100 or other information that can be displayed may be accumulated in the storage unit or the storage device, be made accessible from the cryopump monitor 130 if necessary, and be displayed on the cryopump monitor 130.
In addition, the cryopump monitor 130 may visually present information and present the information audibly or by other means.
A monitoring method of the cryopump system 100 according to the embodiment includes connecting the cryopump monitor 130 to the network 120 and disposing the cryopump monitor outside the casing 206 of the vacuum process device 200. For example, the cryopump monitor 130 is connected to the cryopump controller 110 using the fourth communication line 124. Accordingly, the cryopump monitor 130 is connected to the network 120 and is disposed outside the casing 206 of the vacuum process device 200. Since the cryopump controller 110 is disposed in the casing 206 of the vacuum process device 200, it can be difficult to perform connection between the cryopump monitor 130 and the cryopump controller 110 during the operation of the cryopump system 100 (that is, during the operation of the vacuum process device 200). Accordingly, it is preferable to perform connecting work of the cryopump monitor 130 before the operation of the cryopump system 100.
The monitoring method of the cryopump system 100 further includes displaying information related to the cryopump 10, which is transmitted via the network 120, on the cryopump monitor 130. In addition, the method may include displaying information related to the compressor 12, which is transmitted via the network 120, on the cryopump monitor 130. These types of display may be performed during the operation of the cryopump system 100 or may be performed during the operation stop of the cryopump system 100.
As described above, all of the information related to the cryopump 10 and the information related to the compressor 12 are put together in the cryopump controller 110 in the cryopump system 100. The network 120 used in communication in the cryopump system 100 is configured to broadcast communication data (including the information related to the cryopump 10 (or the compressor 12)) to all nodes, for example, like RS-485. Therefore, by connecting the cryopump monitor 130 to the network 120 (for example, the cryopump controller 110), the cryopump monitor 130 can acquire (so to speak, intercept) communication data transmitted between the cryopump controller 110 and the cryopump 10 (or the compressor 12) via the network 120. In this manner, the cryopump monitor 130 can display the information related to the cryopump 10 (or the compressor 12) based on the acquired communication data.
The monitoring method of the cryopump system 100 may further include controlling the cryopump system 100 in accordance with the operation of the cryopump monitor 130. As described above, the cryopump controller 110 can receive an operation signal generated as the operator operates the operation unit 132 via the input and output circuit 134 (and the fourth communication line 124) and control the cryopump 10 (or the compressor 12) in accordance with the operation signal. Examples of the operation of the cryopump system 100, which is performed by the operator using the cryopump monitor 130, include the following, and are not limited thereto.

- The on or off state of the cryopump 10
- The regeneration start of the cryopump 10 and selection of a regeneration mode
- Operations of devices mounted on the cryopump 10 (for example, opening and closing operations of the rough valve 24, the purge valve 26, and the vent valve 28 and the change of the operating frequency of the expander motor 30)
- Calibration of sensors mounted on the cryopump 10, such as the pressure sensor 21 (for example, atmospheric pressure adjustment and zero point adjustment)
- The on or off state of the compressor 12

As described at the beginning of the present application, it would be convenient if information related to the cryopump 10 can be seen during the operation of the vacuum process device 200. Such information is particularly useful, when an abnormality occurs in the cryopump system 100, in identifying a cause of the abnormality and returning to a normal state.
However, since existing cryopump products are not provided with such an information display tool in many cases, it requires long time to analyze the abnormality and returning to normal in some cases. In such a case, since the cryopump system 100 is connected to the vacuum process device 200, information related to the cryopump system 100 may be available from the vacuum process device 200. However, in reality, the vacuum process device 200 is usually not designed to have access to all types of information related to the cryopump system 100. For this reason, the method does not necessarily ensure that information necessary for analyzing the abnormality and returning to normal is available. In addition, there can also be a case where a communication abnormality between the host controller 204 of the vacuum process device 200 and the cryopump system 100 is suspected as one of causes of the abnormality.
Thus, a plan to integrally incorporate a display unit that displays information into the cryopump 10 is conceivable. However, even in such a case, in reality, information cannot be seen during operation in many cases. This is because even when the display unit is provided, the display unit is hidden at a place that cannot be seen from the outside in most cases as the cryopump 10 is housed in the vacuum process device 200. In addition, for safety reasons such as avoiding contact with dangers such as a high voltage and a high energy beam used in the vacuum process device 200, internal components of the vacuum process device 200, such as the cryopump 10, are required to be physically inaccessible to humans during the operation of the vacuum process device 200. When the operation of the vacuum process device 200 is stopped, the display unit can be seen by approaching the cryopump 10, but the operation stop of the device is not desirable since the operation stop causes a decrease in productivity.
On the contrary, in the embodiment, the cryopump monitor 130 is disposed outside the casing 206 of the vacuum process device 200, and information related to the cryopump 10 (and/or the compressor 12) is displayed on the cryopump monitor 130. For this reason, the operator can easily confirm the displayed information related to the cryopump 10 (and/or the compressor 12) at hand during the operation of the vacuum process device 200. Necessary information is available to the operator at a safe place at any time by looking at the cryopump monitor 130. When an abnormality occurs in the cryopump system 100, the operator can quickly proceed to identification of a cause of the abnormality and returning to the normal state, using the information obtained from the cryopump monitor 130.
In addition, in the embodiment, the cryopump monitor 130 is connected to the network 120 without going through the host controller 204. For example, the cryopump monitor 130 is connected to the network 120 as being directly connected to the cryopump controller 110. Accordingly, even in a case where an abnormality of the host controller 204 or a communication abnormality between the cryopump controller 110 and the host controller 204 is suspected, the cryopump monitor 130 can obtain information from the cryopump controller 110 and display the information. In addition, the cryopump monitor 130 can also obtain information that cannot be obtained by going through the host controller 204 (information on a cryopump that is not a monitoring target of the host controller 204) from the cryopump controller 110 and display the information.
Further, in the embodiment, the cryopump monitor 130 includes the operation unit or operation panel 132 for operating the cryopump system 100. For this reason, the cryopump system 100 can perform a necessary operation from the cryopump monitor 130 apart from operating the cryopump system 100 via the host controller 204 of the vacuum process device 200.
The present invention has been described based on the example. It is clear for those skilled in the art that the present invention is not limited to the embodiment, various design changes are possible, various modification examples are possible, and such modification examples are also within the scope of the present invention.
In the embodiment described above, each of the compressor 12 and the cryopump monitor 130 is individually connected to the cryopump controller 110 by a communication cable (the third communication line 123 and the fourth communication line 124). In one embodiment, the third communication line 123 and the fourth communication line 124 may be aligned by one communication cable branched at an end portion, and the compressor 12 and the cryopump monitor 130 may be connected to the cryopump controller 110 using the one communication cable.
Instead of directly connecting the cryopump monitor 130 to the cryopump controller 110, the cryopump monitor 130 may be connected to the network 120 as being connected to the compressor 12 in a wired manner and be disposed outside the casing 206 of the vacuum process device 200. In this case, the connecting work of the cryopump monitor 130 may be performed before the operation of the cryopump system 100 or may be performed during the operation of the cryopump system 100. In addition, the cryopump monitor 130 may be connected to the network 120 as being connected to other nodes (for example, the cryopump 10) on the network 120, and be disposed outside the casing 206 of the vacuum process device 200.
The cryopump monitor 130 may be integrally mounted on the compressor 12. For example, a configuration where the operation panel 62 provided in the compressor 12 is operated as the cryopump monitor 130 may be adopted.
The cryopump monitor 130 may be capable of switching between enabling and disabling at least some of display functions (and/or operation functions). For example, some of the display functions, such as displaying internal parameters of the cryopump 10 may be locked by, for example, a password such that the functions cannot be used in an initial state of the cryopump monitor 130. The cryopump monitor 130 may enable the display functions by releasing this lock.
The connection of the cryopump monitor 130 to the network 120 may be wireless. For example, the compressor 12 may be connected to the cryopump controller 110 in a wired manner, and the cryopump monitor 130 and the compressor 12 may be wirelessly connected. Since both of the cryopump monitor 130 and the compressor 12 are disposed outside the vacuum process device 200 and are disposed close to each other, carrier waves for wireless communication are easily transmitted to each other well. Alternatively, if possible, the cryopump controller 110 and the cryopump monitor 130 may be wirelessly connected.
In the embodiment described above, the cryopump monitor 130 includes the operation unit 132, and accordingly, has the operation function of the cryopump system 100. However, in one embodiment, the cryopump monitor 130 may have only the display function without having the operation function.
At least one cryopump 10 provided in the cryopump system 100 may be a cold trap. Typically, the cold trap is cooled by a single-stage cryocooler, is disposed at an inlet of a high vacuum pump, such as a turbo molecular pump, and mainly condenses and exhausts steam on a cold trap surface. The cryopump monitor 130 may display information related to the cold trap.
It should be understood that the invention is not limited to the above-described embodiment, but may be modified into various forms on the basis of the spirit of the invention. Additionally, the modifications are included in the scope of the invention.

Claims

What is claimed is:

1. A cryopump system mounted on a vacuum process device, the cryopump system comprising:

at least one cryopump;

a cryopump controller that controls the cryopump;

a network that connects the cryopump to the cryopump controller and transmits information related to the cryopump between the cryopump and the cryopump controller; and

a cryopump monitor that is connected to the network and displays the information related to the cryopump, which is transmitted via the network,

wherein the cryopump controller is disposed in a casing of the vacuum process device, and the cryopump monitor is disposed outside the casing of the vacuum process device.

2. The cryopump system according to claim 1,

wherein the cryopump controller is connectable to a host controller provided in the vacuum process device, and

the cryopump monitor is connected to the network without going through the host controller.

3. The cryopump system according to claim 1, further comprising:

at least one compressor that is disposed outside the casing of the vacuum process device and is connected to the network,

wherein the cryopump monitor is provided in the compressor.

4. The cryopump system according to claim 3,

wherein the cryopump monitor displays information related to the compressor, which is transmitted via the network.

5. The cryopump system according to claim 1,

wherein the cryopump monitor includes an operation panel that is used for operating the cryopump system.

6. A method of monitoring a cryopump system mounted on a vacuum process device,

wherein the cryopump system includes at least one cryopump, a cryopump controller that is disposed in a casing of the vacuum process device and controls the cryopump, and a network that connects the cryopump to the cryopump controller and transmits information related to the cryopump between the cryopump and the cryopump controller,

the method comprising:

connecting a cryopump monitor to the network and disposing the cryopump monitor outside the casing of the vacuum process device; and

displaying the information related to the cryopump, which is transmitted via the network, on the cryopump monitor.