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JP-7856447-B2 - Cryopumps and methods for operating cryopumps

JP7856447B2JP 7856447 B2JP7856447 B2JP 7856447B2JP-7856447-B2

Inventors

  • 中西 嵩裕

Assignees

  • 住友重機械工業株式会社

Dates

Publication Date
20260511
Application Date
20220218

Claims (9)

  1. A cryopump that can be mounted in a vacuum chamber via a gate valve, Refrigeration unit, A cryopump comprising: a controller configured to detect whether the gate valve is closed or not, and to control the refrigerator so that the cooling capacity of the refrigerator when the gate valve is closed is increased compared to when the gate valve is open.
  2. The cryopump according to claim 1, characterized in that the controller is configured to receive a gate valve signal indicating the open/closed state of the gate valve and to detect whether or not the gate valve is closed based on the gate valve signal.
  3. The cryopump according to claim 1, characterized in that the controller is configured to acquire the heat load to the chiller and to detect whether the gate valve is closed based on the acquired heat load.
  4. The aforementioned refrigerator is configured to have a variable operating frequency. The cryopump according to any one of claims 1 to 3, characterized in that the controller is configured to operate the refrigerator at an operating frequency of a first lower limit or higher when the gate valve is open, and to operate the refrigerator at an operating frequency of a second lower limit or higher than the first lower limit when the gate valve is closed.
  5. The aforementioned refrigerator is configured to have a variable operating frequency. The cryopump further includes a temperature sensor for measuring the cooling temperature of the refrigerator, The cryopump according to any one of claims 1 to 3, characterized in that the controller is configured to determine the operating frequency of the refrigerator so that the cooling temperature measured by the temperature sensor matches a first target temperature when the gate valve is open, and to determine the operating frequency of the refrigerator so that the cooling temperature measured by the temperature sensor matches a second target temperature lower than the first target temperature when the gate valve is closed, and to operate the refrigerator at the determined operating frequency.
  6. The aforementioned refrigerator is equipped with a heating device, The cryopump according to any one of claims 1 to 4, characterized in that the controller is configured to operate the heating device at a first output when the gate valve is open, and to operate the heating device at a second output lower than the first output or not to operate it when the gate valve is closed.
  7. A method for operating a cryopump, wherein the cryopump is mountable to a vacuum chamber via a gate valve and is equipped with a refrigerator, and the method is: To detect whether the gate valve is closed or not, A method characterized by increasing the cooling capacity of the refrigerator when the gate valve is closed compared to when the gate valve is open.
  8. A refrigerator and A cryopump comprising: a controller that detects whether the regeneration of the cryopump is complete, and controls the refrigerator to temporarily increase its cooling capacity after the completion of the regeneration.
  9. A method for operating a cryopump, wherein the cryopump is equipped with a refrigerator, and the method is: To detect whether the regeneration of the cryopump has been completed, A method characterized by comprising temporarily increasing the cooling capacity of the refrigerator after the completion of the aforementioned regeneration.

Description

This invention relates to a cryopump and a method for operating a cryopump. A cryopump is a vacuum pump that captures and exhausts gas molecules by condensation or adsorption onto a cryopanel cooled to extremely low temperatures. Cryopumps are commonly used to achieve the clean vacuum environment required in semiconductor circuit manufacturing processes and other applications. Japanese Patent Publication No. 2012-237293 This is a schematic diagram showing a cryopump according to an embodiment.This is a block diagram schematically showing the configuration of the control device for the cryopump according to the embodiment.This flowchart shows an example of how to operate a cryopump according to an embodiment.Figure 4(a) shows the operation of a cryopump according to a comparative example, and Figure 4(b) shows the operation of a cryopump according to an embodiment.This flowchart shows another example of how to operate the cryopump according to the embodiment.This is a block diagram schematically showing the configuration of a control device for a cryopump according to another embodiment. The embodiments for carrying out the present invention will be described in detail below with reference to the drawings. In the description and drawings, identical or equivalent components, members, and processes are denoted by the same reference numerals, and redundant explanations are omitted as appropriate. The scale and shape of the illustrated parts are set for convenience to facilitate explanation and are not to be interpreted restrictively unless otherwise specified. The embodiments are illustrative and do not limit the scope of the present invention in any way. Not all features or combinations thereof described in the embodiments are necessarily essential to the invention. Figure 1 is a schematic diagram showing a cryopump 10 according to an embodiment. Figure 2 is a schematic block diagram showing the configuration of the control device for the cryopump 10 according to an embodiment. The cryopump 10 can be mounted via a gate valve 102 to a vacuum chamber 100 of, for example, an ion implantation apparatus, a sputtering apparatus, a deposition apparatus, or other vacuum process apparatus. Figure 1 shows a portion of the vacuum chamber 100 and gate valve 102 together with the cryopump 10. The cryopump 10 is mounted to the vacuum chamber 100 via a gate valve 102 and is used to raise the vacuum level inside the vacuum chamber 100 to the level required for the desired vacuum process. The cryopump 10 has a cryopump intake port (hereinafter also simply referred to as the "intake port") 12 for receiving the gas to be exhausted from the vacuum chamber 100. The gas enters the internal space of the cryopump 10 from the vacuum chamber 100 through the gate valve 102 and the intake port 12. In the following, the terms "axial direction" and "radial direction" may be used to clearly represent the positional relationships of the components of the cryopump 10. The axial direction of the cryopump 10 represents the direction passing through the intake port 12 (i.e., the direction along the central axis of the cryopump 10, which is the up and down direction in the figure), and the radial direction represents the direction along the intake port 12 (the direction perpendicular to the central axis of the cryopump 10, which is the left and right direction in the figure). For convenience, relative proximity to the intake port 12 in the axial direction may be referred to as "up," and relative distance as "down." In other words, relative distance from the bottom of the cryopump 10 may be referred to as "up," and relative proximity as "down." Regarding the radial direction, proximity to the center of the intake port 12 may be referred to as "inside," and proximity to the periphery of the intake port 12 may be referred to as "outside." Note that these expressions are not related to the arrangement when the cryopump 10 is installed in the vacuum chamber 100. For example, the cryopump 10 may be mounted in the vacuum chamber 100 with the intake port 12 facing downwards in the vertical direction. Furthermore, the direction surrounding the axial direction is sometimes called the "circumferential direction." The circumferential direction is the second direction along the intake port 12, and is a tangential direction perpendicular to the radial direction. The cryopump 10 comprises a refrigerator 14, a cryopump vessel 16, a first-stage cryopanel 18, and a cryopanel unit 20. The first-stage cryopanel 18 may also be referred to as the high-temperature cryopanel section or the 100K section. The cryopanel unit 20 is the second-stage cryopanel and may also be referred to as the low-temperature cryopanel section or the 10K section. The refrigerator 14 is a cryogenic refrigerator, such as a Gifford-McMahon type refrigerator (a so-called GM refrigerator). The refrigerator 14 is a two-stage refrigerator and comprises a first cooling stage 22 and a second cooling