Cryopump, method for manufacturing a cryopump, and method for using a cryopump

Abstract

To protect a cryopump employing an antivibration structure.SOLUTION: A cryopump 10 comprises: a cryopump vacuum container 12: a cryogenic refrigerator 14; an antivibration structure 16 connecting the cryogenic refrigerator 14 to the cryopump vacuum container 12; and a removable restraining tool 70 that connects the cryogenic refrigerator 14 to the cryopump vacuum container 12 in parallel with the antivibration structure 16, and restrains both the expansion and contraction of the antivibration structure 16 between the cryogenic refrigerator 14 and the cryopump vacuum container 12.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a cryopump, a method for manufacturing a cryopump, and a method for using the same.

Background Art

[0002] A cryopump is a vacuum pump that captures gas molecules by condensation or adsorption on a cryopanel cooled to an extremely low temperature and evacuates them. A cryopump is installed in a vacuum process apparatus that performs a vacuum process such as, for example, a semiconductor circuit manufacturing process, and provides a vacuum environment.

[0003] A cryopump includes an extremely low temperature refrigerator and a cryopump vacuum vessel that is attached to the vacuum process apparatus and supports the extremely low temperature refrigerator. The cryopanel is housed in the cryopump vacuum vessel and cooled by the extremely low temperature refrigerator. The extremely low temperature refrigerator is configured to periodically vary the pressure of the refrigerant gas inside, and such pressure fluctuations can vibrate the extremely low temperature refrigerator. Also, if a movable member such as a displacer and its drive source are incorporated, as in, for example, a Gifford-McMahon (GM) refrigerator, these also vibrate the extremely low temperature refrigerator. Vibration generated from the extremely low temperature refrigerator can be transmitted to the vacuum process apparatus via the cryopump vacuum vessel. Vibration may be one factor that can affect the quality of the vacuum process. Therefore, in order to suppress the transmission of vibration generated by the extremely low temperature refrigerator, it has been proposed to connect the extremely low temperature refrigerator to the cryopump vacuum vessel via a vibration isolation structure.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The proposed cryopump with vibration isolation structure incorporates vibration-damping materials, such as rubber, to suppress the transmission of vibrations. Therefore, the rigidity of the connection between the cryogenic refrigerator, which includes this vibration isolation structure, and the cryopump vacuum vessel may be lower than that of a conventional cryopump without a vibration isolation structure. During the transportation of the cryopump, such as from the manufacturing plant to the actual site of use, various loads and shocks may act on the cryopump. If the vibration isolation structure deforms due to such loads, there is a risk that components inside the cryopump may come into contact with each other or, in some cases, be damaged.

[0006] One exemplary objective of a certain aspect of the present invention is the protection of a cryopump employing a vibration-damping structure. [Means for solving the problem]

[0007] According to one aspect of the present invention, the cryopump comprises a cryogenic refrigerator, a cryopump vacuum vessel, a vibration isolation structure connecting the cryogenic refrigerator to the cryopump vacuum vessel, and a removable restraint that connects the cryogenic refrigerator to the cryopump vacuum vessel in parallel with the vibration isolation structure and restrains both the extension and contraction of the vibration isolation structure between the cryogenic refrigerator and the cryopump vacuum vessel.

[0008] According to one aspect of the present invention, the cryopump comprises a cryogenic refrigerator, a cryopump vacuum vessel, a vibration-damping structure connecting the cryogenic refrigerator to the cryopump vacuum vessel, and a first mounting portion and a second mounting portion to which removable restraints are attached that restrain both the extension and contraction of the vibration-damping structure between the cryogenic refrigerator and the cryopump vacuum vessel. The first mounting portion is formed on the cryopump vacuum vessel or on the end of the vibration-damping structure on the cryopump vacuum vessel side. The second mounting portion is formed on the cryogenic refrigerator or on the end of the vibration-damping structure on the cryogenic refrigerator side.

[0009] According to one aspect of the present invention, a method for manufacturing a cryopump comprises preparing a cryopump and attaching a removable restraint to the cryopump. The cryopump comprises a cryogenic refrigerator, a cryopump vacuum vessel, and a vibration-damping structure that connects the cryogenic refrigerator to the cryopump vacuum vessel. The removable restraint connects the cryogenic refrigerator to the cryopump vacuum vessel in parallel with the vibration-damping structure and restrains both the extension and contraction of the vibration-damping structure between the cryogenic refrigerator and the cryopump vacuum vessel.

[0010] According to one aspect of the present invention, a method of using a cryopump comprises preparing a cryopump to which a removable restraint is attached, and removing the removable restraint from the cryopump. The cryopump comprises a cryogenic refrigerator, a cryopump vacuum vessel, and a vibration isolation structure connecting the cryogenic refrigerator to the cryopump vacuum vessel. The removable restraint connects the cryogenic refrigerator to the cryopump vacuum vessel in parallel with the vibration isolation structure and restrains both the extension and contraction of the vibration isolation structure between the cryogenic refrigerator and the cryopump vacuum vessel. [Effects of the Invention]

[0011] According to the present invention, a cryopump employing a vibration-damping structure can be protected. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic diagram showing a cryopump according to an embodiment. [Figure 2] This is an exploded view schematically showing a vibration isolation structure according to an embodiment. [Figure 3] Figure 3(a) is a schematic plan view of the vibration isolation structure according to the embodiment, as seen from the first flange side, and Figure 3(b) is a schematic plan view of the vibration isolation structure according to the embodiment, as seen from the second flange side. [Figure 4] Figure 4(a) schematically shows the AA section of Figure 3(b), and Figure 4(b) schematically shows the BB section of Figure 3(b). [Figure 5]Figure 5(a) is a schematic perspective view of the first annular support member according to the embodiment, and Figure 5(b) is a schematic perspective view of the second annular support member according to the embodiment. [Figure 6] This diagram schematically shows a part of the cryopump according to the embodiment. [Figure 7] This diagram schematically shows a part of the cryopump according to the embodiment. [Figure 8] This diagram schematically shows a part of the cryopump according to the embodiment. [Figure 9] Figure 9(a) is a flowchart showing an example of a cryopump manufacturing method according to the embodiment, and Figure 9(b) is a flowchart showing an example of a cryopump usage method according to the embodiment. [Modes for carrying out the invention]

[0013] 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 descriptions will be omitted as appropriate. The scale and shape of the illustrated parts are set for convenience to facilitate the 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.

[0014] Figure 1 is a schematic diagram showing a cryopump 10 according to an embodiment. The cryopump 10 is used to raise the vacuum level inside the vacuum chamber to the level required for a desired vacuum process, for example, by being installed in the vacuum chamber of an ion implantation apparatus, sputtering apparatus, deposition apparatus, or other vacuum process apparatus.

[0015] The cryopump 10 comprises a cryopump vacuum vessel 12, a cryogenic refrigerator 14, a vibration-damping structure 16, a first-stage cryo-panel 18, and a second-stage cryo-panel 20.

[0016] As will be described later, the cryogenic refrigerator 14 is attached to the cryopump vacuum vessel 12 via the vibration isolation structure 16, whereby the cryopump vacuum vessel 12 is vibration-isolated from the cryogenic refrigerator 14.

[0017] The cryopump vacuum vessel 12 includes a vacuum vessel main body 12a having an intake flange 22 and a refrigerator housing cylinder 12b having a vacuum vessel flange 24. The vacuum vessel main body 12a is a cylinder (for example, a circular cylinder) with one end open as the cryopump intake port 10a and the other end closed, and the intake flange 22 is provided on the vacuum vessel main body 12a so as to surround the cryopump intake port 10a. Usually, the intake flange 22 is attached to the gate valve. The gas in the vacuum chamber of the vacuum process apparatus enters the cryopump 10 through the gate valve and the cryopump intake port 10a. Since the illustrated cryopump 10 is a so-called horizontal cryopump, the refrigerator housing cylinder 12b is a cylinder (for example, a circular cylinder) with both ends open, one end is joined to the refrigerator insertion hole formed on the side surface of the vacuum vessel main body 12a, and the vacuum vessel flange 24 is provided at the other end.

[0018] Note that the cryopump 10 may be a so-called vertical type. In that case, the vacuum vessel main body 12a has the refrigerator insertion hole on the bottom surface instead of the side surface, and the refrigerator housing cylinder 12b is joined to the refrigerator insertion hole on the bottom surface of the vacuum vessel main body 12a.

[0019] The cryogenic refrigerator 14 comprises a room temperature section 14a, a first cooling stage 14b, and a second cooling stage 14c, and is inserted into the vacuum vessel body 12a through a vibration-damping structure 16 and a refrigerator housing cylinder 12b. The room temperature section 14a is located outside the cryopump vacuum vessel 12. On the other hand, the first cooling stage 14b and the second cooling stage 14c are located inside the cryopump vacuum vessel 12. For example, the first cooling stage 14b is located in the internal space of the refrigerator housing cylinder 12b, and the second cooling stage 14c is located in the internal space of the vacuum vessel body 12a. The first cooling stage 14b may be located near the joint between the refrigerator housing cylinder 12b and the vacuum vessel body 12a. The cryogenic refrigerator 14 is, as an example, a two-stage GM refrigerator, but it may also be other cryogenic refrigerators such as pulse tube refrigerators.

[0020] The first-stage cryo-panel 18 is thermally coupled to the first cooling stage 14b and is located inside the vacuum vessel body 12a. The first-stage cryo-panel 18 is structurally supported by the first cooling stage 14b so as not to be in contact with the cryopump vacuum vessel 12. The first-stage cryo-panel 18 is also called a radiation shield and often has a cylindrical shape with a slightly smaller diameter than the vacuum vessel body 12a. The first-stage cryo-panel 18 may have a cryopump intake panel, for example, in the shape of a plate (e.g., disc) or louver, which is thermally coupled to the radiation shield and located in or near the cryopump intake port 10a.

[0021] The second-stage cryopanel 20 is thermally coupled to the second cooling stage 14c and is located within the vacuum vessel body 12a. The second-stage cryopanel 20 is structurally supported by the second cooling stage 14c so as to be non-contact with the first-stage cryopanel 18. The second cooling stage 14c and the second-stage cryopanel 20 are surrounded by the first-stage cryopanel 18.

[0022] The arrangement and shape of the first-stage cryo-panel 18 and the second-stage cryo-panel 20 are not limited to the specific ones shown in the figures, and various known configurations can be adopted as appropriate.

[0023] The first-stage cryo-panel 18 is cooled to a first cooling temperature by the first cooling stage 14b, and the second-stage cryo-panel 20 is cooled to a second cooling temperature by the second cooling stage 14c. The second cooling temperature is lower than the first cooling temperature. The first cooling temperature may be in the range of approximately 65-120K or approximately 80-100K. The second cooling temperature may be in the range of approximately 10-20K.

[0024] Therefore, the first stage cryopanel 18 is supplied with, for example, water vapor, which has a vapor pressure (for example, 10) at the first cooling temperature. -8 A sufficiently low vapor pressure gas (also called a Type 1 gas), such as below Pa, is condensed. In the second stage cryopanel 20, a gas with a sufficiently low vapor pressure at the second cooling temperature (also called a Type 2 gas), such as argon, nitrogen, or oxygen, is condensed. The second stage cryopanel 20 may also be equipped with an adsorbent such as activated carbon, in which case a gas with a vapor pressure that is not sufficiently low at the second cooling temperature (also called a Type 3 gas), such as hydrogen, is adsorbed onto the adsorbent. In this way, the cryopump 10 can exhaust various gases by condensation or adsorption and provide a desired vacuum environment.

[0025] The room temperature section 14a of the cryogenic refrigerator 14 has a refrigerator flange 26. In a typical cryopump, the refrigerator flange 26 is fastened to the vacuum vessel flange 24, thereby allowing the cryogenic refrigerator 14 to be attached to the cryopump vacuum vessel 12. However, in the cryopump 10 according to this embodiment, the vibration isolation structure 16 connects the refrigerator flange 26 to the vacuum vessel flange 24. The cryogenic refrigerator 14 is mounted to the cryopump vacuum vessel 12 via the vibration isolation structure 16. Therefore, the cryogenic refrigerator 14 is not directly attached to the cryopump vacuum vessel 12.

[0026] The vibration isolation structure 16 comprises a first flange 28, a second flange 30, and an annular laminated vibration isolation body 32 disposed between the first flange 28 and the second flange 30. The annular laminated vibration isolation body 32 comprises a first annular vibration isolation material 38, a first annular support member 40, an intermediate annular vibration isolation material 42, a second annular support member 44, and a second annular vibration isolation material 46.

[0027] The first flange 28 is attached to the vacuum vessel flange 24 and fixed to the cryopump vacuum vessel 12. For example, the first flange 28 is fastened to the vacuum vessel flange 24 by a plurality of first fastening bolts 34. The second flange 30 is attached to the refrigerator flange 26 and fixed to the room temperature section 14a of the cryogenic refrigerator 14. For example, the second flange 30 is fastened to the refrigerator flange 26 by a plurality of second fastening bolts 36.

[0028] In the illustrated example, since both the vacuum vessel flange 24 and the refrigerator flange 26 have an annular shape, the vibration isolation structure 16 also has an annular shape. However, if the flange to which the vibration isolation structure 16 is attached has another shape, such as a rectangle, the vibration isolation structure 16 may also have another shape, such as a rectangular tube.

[0029] Figure 2 is an exploded view schematically showing the vibration isolation structure 16 according to the embodiment. Figure 3(a) is a schematic plan view of the vibration isolation structure 16 according to the embodiment as seen from the first flange 28 side, and Figure 3(b) is a schematic plan view of the vibration isolation structure 16 according to the embodiment as seen from the second flange 30 side. Figure 4(a) schematically shows the AA cross section of Figure 3(b), and Figure 4(b) schematically shows the BB cross section of Figure 3(b). Furthermore, Figure 5(a) is a schematic perspective view of the first annular support member 40 according to the embodiment, and Figure 5(b) is a schematic perspective view of the second annular support member 44 according to the embodiment.

[0030] From the first flange 28 toward the second flange 30, the first annular vibration-damping material 38, the first annular support member 40, the intermediate annular vibration-damping material 42, the second annular support member 44, and the second annular vibration-damping material 46 are arranged in this order to form an annular laminated vibration-damping body 32.

[0031] Each of these components of the annular laminated vibration damper 32 has a ring shape and is arranged coaxially adjacent to one another along the central axis direction of the annular laminated vibration damper 32. The ring shapes of each component may have a common inner and outer diameter. The outer diameter of the vibration damping structure 16 is determined by the outer diameters of the first flange 28 and the second flange 30, but the outer diameter of the annular laminated vibration damper 32 is smaller, and the annular laminated vibration damper 32 is housed in the space between the first flange 28 and the second flange 30.

[0032] The first annular support member 40 and the second annular support member 44 are formed of a metallic material such as stainless steel, or other suitable structural material, similar to the first flange 28 and the second flange 30. The first annular vibration damping material 38, the intermediate annular vibration damping material 42, and the second annular vibration damping material 46 are formed of rubber, for example. Alternatively, the first annular vibration damping material 38, the intermediate annular vibration damping material 42, and the second annular vibration damping material 46 may be formed of a synthetic resin such as gel or fluororesin, or a soft metal such as aluminum, or other vibration damping material. The first annular vibration damping material 38, the intermediate annular vibration damping material 42, and the second annular vibration damping material 46 may be formed of the same material or of different materials.

[0033] The vibration isolation characteristics of the vibration isolation structure 16 (e.g., the relationship between vibration frequency and vibration transmittance) may be adjusted by selecting the materials of these annular vibration isolation materials (38, 42, 46). The vibration isolation characteristics of the vibration isolation structure 16 may also be adjusted by selecting the dimensions of the annular vibration isolation materials (e.g., the thickness in the axial direction of the annular laminated vibration isolation body 32, the contact area with adjacent annular support members, etc.). Furthermore, the vibration isolation characteristics of the vibration isolation structure 16 may also be adjusted by selecting the dimensions and / or materials of the annular support members (40, 44).

[0034] In the vibration isolation structure 16 according to the embodiment, the second annular support member 44 is fixed to the first flange 28 and the first annular support member 40 is fixed to the second flange 30 so that the first flange 28 and the second annular support member 44 are insulated from vibration from the second flange 30 and the first annular support member 40. The vibration isolation structure 16 includes a first fastening member 48 and a second fastening member 50 to fix the first flange 28, the second flange 30, and the annular laminated vibration isolation body 32 to each other.

[0035] The first fastening member 48 fixes the second annular support member 44 to the first flange 28 so as to sandwich and hold the first annular vibration-damping material 38, the first annular support member 40, and the intermediate annular vibration-damping material 42 between the first flange 28 and the second annular support member 44.

[0036] The vibration isolation structure 16 has a first fastening hole 49 that penetrates the second annular support member 44, the intermediate annular vibration isolation material 42, the first annular support member 40, and the first annular vibration isolation material 38, and reaches the first flange 28. The first fastening member 48 is inserted into the first fastening hole 49, and the second annular support member 44 is fastened to the first flange 28 by the first fastening member 48. The first annular vibration isolation material 38, the first annular support member 40, and the intermediate annular vibration isolation material 42, which are sandwiched between the first flange 28 and the second annular support member 44, are subjected to a fastening force by the first fastening member 48.

[0037] In the illustrated example, the first fastening member 48 is a countersunk bolt, and the first fastening hole 49 is a countersunk hole in the second annular support member 44, with the head of the first fastening member 48 housed in the second annular support member 44. The first fastening hole 49 is also a bolt hole in the first flange 28, thereby fastening the first fastening member 48 to the second annular support member 44 and the first flange 28. The first fastening hole 49 does not penetrate the first flange 28. Multiple first fastening members 48 and first fastening holes 49 are provided at equal angular intervals in the circumferential direction (for example, 8 locations).

[0038] The first fastening member 48 is positioned so as not to be in contact with the first annular support member 40. The first annular support member 40 has a first through-hole 52 that is larger in diameter than the first fastening member 48. The first through-hole 52 is a so-called oversized hole formed in the first annular support member 40 and is part of the first fastening hole 49. The first fastening member 48 passes through the first through-hole 52 with some play between it and the first annular support member 40. Therefore, no vibration transmission path is formed between the first fastening member 48 and the first annular support member 40. Similar to the first through-hole 52 in the first annular support member 40, the first annular vibration-damping material 38 and the intermediate annular vibration-damping material 42 also have through-holes through which the first fastening member 48 passes. These through-holes are, for example, circular through-holes, but they may be through-holes of other shapes, such as rectangles.

[0039] Furthermore, the first fastening member 48 is positioned so as not to be in contact with the second flange 30. The head of the first fastening member 48 is supported by the second annular support member 44, and the second annular vibration-damping material 46 is inserted between the second flange 30 and the second annular support member 44, so the first fastening member 48 does not come into contact with the second flange 30.

[0040] The second fastening member 50 fixes the first annular support member 40 to the second flange 30 so as to sandwich and hold the intermediate annular vibration-damping material 42, the second annular support member 44, and the second annular vibration-damping material 46 between the second flange 30 and the first annular support member 40.

[0041] The vibration isolation structure 16 has a second fastening hole 51 that penetrates the second flange 30, the second annular vibration isolation material 46, the second annular support member 44, and the intermediate annular vibration isolation material 42, and reaches the first annular support member 40. The second fastening member 50 is inserted into the second fastening hole 51, and the second flange 30 is fastened to the first annular support member 40 by the second fastening member 50. The intermediate annular vibration isolation material 42, the second annular support member 44, and the second annular vibration isolation material 46, which are sandwiched between the second flange 30 and the first annular support member 40, are subjected to a fastening force by the second fastening member 50.

[0042] In the illustrated example, the second fastening member 50 is a bolt, and the second fastening hole 51 is a deep counterbore in the second flange 30, with the head of the second fastening member 50 housed in the second flange 30. The second fastening hole 51 is also a bolt hole in the first annular support member 40, thereby fastening the second fastening member 50 to the second flange 30. The second fastening hole 51 penetrates the first annular support member 40. The second fastening member 50 and the second fastening hole 51 are provided at multiple locations (for example, 8 locations) at equal angular intervals in the circumferential direction.

[0043] The second fastening member 50 is positioned so as not to be in contact with the second annular support member 44. The second annular support member 44 has a second through-hole 54 that is larger in diameter than the second fastening member 50. The second through-hole 54 is a so-called oversized hole formed in the second annular support member 44 and is part of the second fastening hole 51. The second fastening member 50 passes through the second through-hole 54 with some play between it and the second annular support member 44. Therefore, no vibration transmission path is formed between the second fastening member 50 and the second annular support member 44. Similar to the second through-hole 54 in the second annular support member 44, the intermediate annular vibration-damping material 42 and the second annular vibration-damping material 46 also have through-holes through which the second fastening member 50 passes. These through-holes are, for example, circular through-holes, but they may be through-holes of other shapes, such as rectangles.

[0044] Furthermore, the second fastening member 50 is positioned so as not to be in contact with the first flange 28. Since the first annular vibration-damping material 38 is inserted between the first flange 28 and the first annular support member 40, the tip of the second fastening member 50 does not reach the first flange 28.

[0045] The intermediate annular vibration-damping material 42 is subjected to a larger axial compressive force than the first annular vibration-damping material 38. This is because the first annular vibration-damping material 38 is compressed only by the fastening force of the first fastening member 48, whereas the intermediate annular vibration-damping material 42 is compressed by the fastening forces of both the first fastening member 48 and the second fastening member 50.

[0046] Therefore, the intermediate annular vibration-damping material 42 is thicker than the first annular vibration-damping material 38 in the direction of the central axis of the annular laminated vibration-damping body 32. This increases the strength of the intermediate annular vibration-damping material 42. The thickness C of the intermediate annular vibration-damping material 42 may be, for example, about 1.5 to 3 times, for example about 2 times, the thickness D of the first annular vibration-damping material 38. The intermediate annular vibration-damping material 42 may be formed from a single material layer having this thickness C. Alternatively, the intermediate annular vibration-damping material 42 may be made by stacking multiple (for example, two) material layers (for example, two layers of the same material layer used as the first annular vibration-damping material 38 may be stacked). Similarly, since a larger axial compressive force acts on the intermediate annular vibration-damping material 42 than on the second annular vibration-damping material 46, the intermediate annular vibration-damping material 42 is thicker than the second annular vibration-damping material 46 in the direction of the central axis of the annular laminated vibration-damping body 32.

[0047] The insertion hole for the annular vibration isolation material may be a notch (for example, U-shaped in plan view) connected to the outer (or inner) circumference of the annular vibration isolation material, instead of a circular through hole. Since the annular vibration isolation material is made of a soft material such as rubber, such a notch may be easier to process than a through hole. Similarly, the insertion hole for the annular support member may also be a notch connected to the outer (or inner) circumference of the annular support member.

[0048] The first fastening member 48 and the second fastening member 50 (i.e., the first fastening hole 49 and the second fastening hole 51) are positioned at the same radial position and at different circumferential positions on the annular laminated vibration damper 32. However, by positioning the first fastening member 48 and the second fastening member 50 at different radial positions, it is also possible for the first fastening member 48 and the second fastening member 50 to be positioned at the same circumferential position on the annular laminated vibration damper 32.

[0049] The second flange 30 is airtightly connected to the first flange 28. A vacuum seal portion 56 is formed between the first flange 28 and the second flange 30. The first flange 28 has a first flange cylindrical portion 28a that extends from its opening toward the second flange 30, and the second flange 30 has a second flange cylindrical portion 30a that extends from its opening toward the first flange 28.

[0050] The outer diameter of the second flange cylinder portion 30a is slightly smaller than the inner diameter of the first flange cylinder portion 28a, and the second flange cylinder portion 30a is inserted into the first flange cylinder portion 28a. A sealing member 56a, such as an O-ring, is placed between the inner circumferential surface of the first flange cylinder portion 28a and the outer circumferential surface of the second flange cylinder portion 30a, thereby forming a vacuum seal portion 56. The sealing member 56a is attached to the outer circumferential surface of the second flange cylinder portion 30a.

[0051] In the vacuum seal portion 56, the dimensional tolerances of the first flange cylindrical portion 28a and the second flange cylindrical portion 30a are defined so that they contact each other only through the sealing member 56a. Therefore, a gap of, for example, about 0.05 to 0.3 mm, or for example, about 0.1 mm, is formed between the inner circumferential surface of the first flange cylindrical portion 28a and the outer circumferential surface of the second flange cylindrical portion 30a, and the first flange 28 and the second flange 30 do not contact each other.

[0052] Furthermore, the radial positional relationship between the first flange cylinder portion 28a and the second flange cylinder portion 30a can be reversed, and the first flange cylinder portion 28a may be inserted into the second flange cylinder portion 30a, with the vacuum seal portion 56 formed between the outer circumferential surface of the first flange cylinder portion 28a and the inner circumferential surface of the second flange cylinder portion 30a.

[0053] The first flange 28 is a vacuum flange that is hermetically connected to the vacuum vessel flange 24, and a first ring groove 58 for housing a sealing member such as an O-ring is formed on the flange end face. The first ring groove 58 is located radially inward from the first bolt hole 34a for the first fastening bolt 34 and radially outward from the first fastening member 48. The second flange 30 is a vacuum flange that is hermetically connected to the refrigerator flange 26, and a second ring groove 60 for housing a sealing member such as an O-ring is formed on the flange end face. The second ring groove 60 is located radially inward from the second fastening member 50. The second bolt hole 36a for the second fastening bolt 36 is formed radially outward from the second fastening member 50.

[0054] The annular laminated vibration damper 32 is positioned radially outward from the vacuum seal portion 56. The annular laminated vibration damper 32 is positioned outside the vacuum environment, surrounding the first flange cylindrical portion 28a and the second flange cylindrical portion 30a. In other words, the annular laminated vibration damper 32 is positioned in the ambient environment, similar to the room temperature portion 14a of the cryogenic refrigerator 14. This makes it easier to design the diameters of the vacuum seal portion 56 and the vacuum flange to be smaller compared to when the annular laminated vibration damper 32 is positioned in a vacuum environment. It also makes it easier to design the diameter of the annular laminated vibration damper 32 to be larger. In that case, the increased area of ​​the annular vibration damping material makes it easier to reduce the spring constant of the vibration damping structure 16 and reduce the vibration transmission coefficient at high frequencies.

[0055] An example of the assembly procedure for the vibration isolation structure 16 is described below. First, the first flange 28 is placed with the first flange cylindrical portion 28a facing upward. The first annular vibration isolation material 38, the first annular support member 40, the intermediate annular vibration isolation material 42, and the second annular support member 44 are stacked on the first flange 28 in this order. These members are stacked on the first flange 28 so as to align the positions of the through holes in each member, thereby forming the first fastening hole 49. The first fastening member 48 is inserted into the first fastening hole 49, and the second annular support member 44 is fastened to the first flange 28.

[0056] Next, the second annular vibration-damping material 46 is placed on top of the second annular support member 44, and then the second flange 30 is attached on top of that. At this time, the second flange cylindrical portion 30a is inserted into the first flange cylindrical portion 28a. Also, by aligning the positions of the through holes of each member, a second fastening hole 51 is formed. The second fastening member 50 is inserted into the second fastening hole 51, and the second flange 30 is fastened to the first annular support member 40. In this way, the vibration-damping structure 16 is assembled.

[0057] In this manner, the first annular support member 40 is sandwiched between the first annular vibration-damping material 38 and the intermediate annular vibration-damping material 42, and is positioned without contact with the first flange 28, the second annular support member 44, and the first fastening member 48. The second annular support member 44 is sandwiched between the second annular vibration-damping material 46 and the intermediate annular vibration-damping material 42, and is positioned without contact with the second flange 30, the first annular support member 40, and the second fastening member 50. Furthermore, as described above, the first flange 28 and the second flange 30 do not directly touch each other.

[0058] Therefore, the vibration isolation structure 16 comprises a first support structure having a first flange 28, a second annular support member 44, and a first fastening member 48, and a second support structure having a second flange 30, a first annular support member 40, and a second fastening member 50, and the first support structure and the second support structure are vibration-insulated from each other by a first annular vibration isolation material 38, an intermediate annular vibration isolation material 42, and a second annular vibration isolation material 46. The first support structure is fixed to the cryopump vacuum vessel 12, and the second support structure is fixed to the cryogenic refrigerator 14.

[0059] In many existing cryopumps, the cryogenic refrigerator is directly fixed to the cryopump vacuum vessel. The cryogenic refrigerator can be a source of vibration due to periodic pressure fluctuations within it and the movement of moving parts such as displacers. Vibrations from the cryogenic refrigerator can be transmitted to the cryopump vacuum vessel and, further, to the vacuum process equipment on which the cryopump is installed.

[0060] In contrast, according to the cryopump 10 of this embodiment, the cryogenic refrigerator 14 is mounted on the cryopump vacuum vessel 12 via a vibration isolation structure 16. The vibration isolation structure 16 comprises a first flange 28 fixed to the cryopump vacuum vessel 12, a second flange 30 fixed to the cryogenic refrigerator 14, and an annular laminated vibration isolation body 32 in which a first annular vibration isolation material 38, a first annular support member 40, an intermediate annular vibration isolation material 42, a second annular support member 44, and a second annular vibration isolation material 46 are arranged in this order from the first flange 28 toward the second flange 30. The second annular support member 44 is fixed to the first flange 28 and the first annular support member 40 is fixed to the second flange 30 so that the first flange 28 and the second annular support member 44 are vibration-insulated from the second flange 30 and the first annular support member 40.

[0061] As a result, the cryopump vacuum vessel 12 is vibrationally isolated from the cryogenic refrigerator 14. Therefore, vibrations transmitted from the cryogenic refrigerator 14 to other equipment can be reduced. The risks that vibrations from the cryogenic refrigerator 14 may pose to the vacuum process equipment are also reduced.

[0062] In the above-described embodiment, a vacuum seal portion 56 is provided inside the vibration isolation structure 16 to maintain a vacuum environment. The vacuum seal portion 56 is formed by a fitting structure (so-called spigot structure) between the first flange 28 and the second flange 30, and a sealing member 56a installed between these two flanges. However, it is also possible to use other structures to ensure the airtightness of the vibration isolation structure 16. For example, the first flange 28 and the second flange 30 may be manufactured as an integrated structure by bellows connection. In this case, the annular laminated vibration isolation body 32 installed between the first flange 28 and the second flange 30 may have a divided structure composed of multiple parts. The annular laminated vibration isolation body 32 may be divided into, for example, multiple arc-shaped (e.g., two semicircular) laminated vibration isolation bodies, and these divided laminated vibration isolation bodies may be connected to each other in an annular shape, or arranged in an annular shape to form the annular laminated vibration isolation body 32.

[0063] However, since the vibration-damping structure 16 has vibration-damping materials such as rubber, its rigidity may be relatively low. The rigidity of the connection between the cryogenic refrigerator 14, which includes the vibration-damping structure 16, and the cryopump vacuum vessel 12 may be lower than that of a conventional cryopump without the vibration-damping structure 16. Therefore, when an unexpected load or impact acts on the cryopump 10, the vibration-damping structure 16 may deform, and there is a risk that nearby components inside the cryopump 10 (for example, the cryopump vacuum vessel 12 and the first-stage cryo-panel 18) may come into contact with each other or, in some cases, be damaged. It is feared that such risks may become apparent during the transportation of the cryopump 10, for example, during transport from the manufacturing plant to the site where it will actually be used.

[0064] Before transport, the cryopump 10 may be packaged in packaging material such as polystyrene foam. However, inexpensive packaging materials have some gaps between them and the cryopump 10. Therefore, due to impact loads during transport, the vibration-damping structure 16 may deform within the packaging material, causing the cryogenic refrigerator 14 to move relative to the cryopump vacuum container 12. As a result, damage may occur inside the cryopump 10 as described above. According to the inventor's considerations, existing packaging materials are less effective at suppressing the movement of the cryogenic refrigerator 14 when the vibration-damping structure 16 is contracted compared to when it is expanded. While tightening the dimensional tolerances of the packaging material could reduce the gap between the packaging material and the cryopump 10, this would increase the manufacturing cost of the packaging material and is therefore undesirable.

[0065] Therefore, in this embodiment, as described below, a restraint 70 can be attached to the cryopump 10 to prevent deformation of the vibration isolation structure 16. When the cryopump 10 is not in use, such as during transport or storage, the restraint 70 is attached to the cryopump 10. The restraint 70, when combined with the vibration isolation structure 16, prevents deformation of the vibration isolation structure 16 and the resulting movement of the cryogenic refrigerator 14 relative to the cryopump vacuum vessel 12. The restraint 70 is removable from the cryopump 10. When the cryopump 10 is in use, that is, when it is installed in a vacuum process apparatus and the apparatus is evacuated, the restraint 70 is removed from the cryopump 10 so that the vibration isolation structure 16 can provide its vibration isolation function.

[0066] Figure 6 is a schematic diagram showing a part of the cryopump 10 according to an embodiment. Figure 6 shows a state in which a removable restraint 70 is attached to the cryopump 10. This restraint 70 connects the cryogenic refrigerator 14 to the cryopump vacuum vessel 12 in parallel with the vibration isolation structure 16, and restrains both the extension and contraction of the vibration isolation structure 16 between the cryogenic refrigerator 14 and the cryopump vacuum vessel 12.

[0067] Figure 1 shows the cryopump 10 without the restraint 70 attached. As shown in Figure 1, the cryopump 10 is provided with a first mounting portion 72 formed on the cryopump vacuum vessel 12 and a second mounting portion 74 formed on the cryogenic refrigerator 14. In this embodiment, the first mounting portion 72 is formed on the outer circumferential surface of the vacuum vessel flange 24, and the second mounting portion 74 is formed on the outer circumferential surface of the refrigerator flange 26.

[0068] The first mounting portions 72 are formed at multiple locations (for example, at least three) in the circumferential direction on the outer surface of the vacuum vessel flange 24. Similarly, the second mounting portions 74 are formed at multiple locations (for example, at least three) in the circumferential direction on the outer surface of the refrigerator flange 26. In this example, four first mounting portions 72 are formed at equal intervals in the circumferential direction on the outer surface of the vacuum vessel flange 24, and four second mounting portions 74 are formed at equal intervals in the circumferential direction on the outer surface of the refrigerator flange 26. The second mounting portions 74 are formed on the outer surface of the refrigerator flange 26 in an arrangement corresponding to the first mounting portions 72 (i.e., at the same circumferential positions as the first mounting portions 72).

[0069] The first mounting portion 72 includes a first seating surface 72a formed on the outer circumferential surface of the vacuum vessel flange 24 and a first screw hole 72b (e.g., a bolt hole) formed in the first seating surface 72a. The first seating surface 72a has a shape that matches the shape of the restraint 70. A seating surface matching the shape of the restraint 70 is also formed on the outer circumferential surface of the first flange 28 of the vibration isolation structure 16 adjacent to the vacuum vessel flange 24, and is continuous with the first seating surface 72a. For example, if the restraint 70 is a flat plate as described later, the first seating surface 72a is also a flat surface. The seating surface formed on the first flange 28 is also a flat surface flush with the first seating surface 72a.

[0070] Similar to the first mounting portion 72, the second mounting portion 74 includes a second seating surface 74a formed on the outer circumferential surface of the refrigeration flange 26 to match the shape of the restraint 70, and a second screw hole 74b (e.g., a bolt hole) formed in the second seating surface 74a. The outer circumferential surface of the second flange 30 of the vibration-damping structure 16 adjacent to the refrigeration flange 26 also has a seating surface formed on it that is continuous with the second seating surface 74a and matches the shape of the restraint 70.

[0071] The restraint 70 is a plate or rod, and as an example, is an elongated flat plate. Alternatively, the restraint 70 may have other suitable shapes, such as an arc-shaped plate that follows the outer surface of the flange. The restraint 70 is made of a highly rigid material, such as a metal material (e.g., stainless steel). Such a highly rigid material has a larger Young's modulus than the vibration-damping material of the vibration-damping structure 16 (e.g., the first annular vibration-damping material 38, the intermediate annular vibration-damping material 42, and the second annular vibration-damping material 46 shown in Figure 1). Therefore, the restraint 70 has a larger Young's modulus in the direction of expansion and contraction of the vibration-damping structure 16 compared to the vibration-damping structure 16. The restraint 70 may be made of a synthetic resin material or other suitable material that has higher rigidity than the vibration-damping material.

[0072] As shown in Figure 6, the removable restraint 70 is attached to the first mounting portion 72 at one end and to the second mounting portion 74 at the other end. A first mounting member 76a and a second mounting member 76b are used to attach the restraint 70 to the first mounting portion 72 and the second mounting portion 74. For example, the first mounting member 76a may be a screw (e.g., a bolt) that screws into the first screw hole 72b, and the second mounting member 76b may be a screw (e.g., a bolt) that screws into the second screw hole 74b. Through holes corresponding to these mounting members are formed at both ends of the restraint 70.

[0073] By bringing one end of the restraint 70 into contact with the first seating surface 72a and inserting the first mounting member 76a into the hole at the other end of the restraint 70 and attaching it to the first screw hole 72b, one end of the restraint 70 is fixed to the first mounting portion 72. Similarly, by bringing the other end of the restraint 70 into contact with the second seating surface 74a and inserting the second mounting member 76b into the hole at the other end of the restraint 70 and attaching it to the second screw hole 74b, the other end of the restraint 70 is fixed to the second mounting portion 74.

[0074] The restraint 70, thus attached to the cryopump 10, extends along the vibration isolation structure 16 from the first mounting portion 72 to the second mounting portion 74, bridging both ends of the vibration isolation structure 16. The restraint 70 is fixed to the vibration isolation structure 16 by the fastening force of the first mounting member 76a and the second mounting member 76b. As a result, the restraint 70 can restrain both the extension and contraction of the vibration isolation structure 16, thereby restraining the movement of the cryogenic refrigerator 14 relative to the cryopump vacuum vessel 12. Therefore, the risk of deformation of the vibration isolation structure 16 due to unexpected loads or impacts that may act on the cryopump 10 during transport, and the resulting damage inside the cryopump 10, can be reduced, thereby protecting the cryopump 10.

[0075] The first mounting portion 72 and the second mounting portion 74 can be arranged in other ways. For example, the first mounting portion 72 may be formed at the end of the vibration-damping structure 16 on the cryopump vacuum vessel 12 side, and the second mounting portion 74 may be formed at the end of the vibration-damping structure 16 on the cryogenic refrigerator 14 side. In the above embodiment, the first flange 28 of the vibration-damping structure 16 is fixed to the vacuum vessel flange 24, and the second flange 30 of the vibration-damping structure 16 is fixed to the refrigerator flange 26. Therefore, the first mounting portion 72 may be formed on the outer circumferential surface of the first flange 28 of the vibration-damping structure 16. Similarly, the second mounting portion 74 may be formed on the outer circumferential surface of the second flange 30 of the vibration-damping structure 16.

[0076] Furthermore, the first mounting portion 72 and the second mounting portion 74 may have other shapes. For example, these mounting portions may have projections instead of screw holes. These projections may be male screws (bolts) with threads formed on their outer surface. In this case, the first mounting member 76a and the second mounting member 76b may be corresponding nuts. The restraint 70 may be fixed to the mounting portion by inserting the mounting portion (projection) into the hole at the end of the restraint 70, bringing the restraint 70 into contact with the seating surface of the mounting portion, and attaching the mounting member to the mounting portion. Alternatively, the first mounting portion 72 and the second mounting portion 74 may have other shapes that engage with and fix the restraint 70. The restraint 70 may also have any shape that can be attached to the mounting portion.

[0077] Figure 7 is a schematic diagram showing a part of the cryopump 10 according to the embodiment. Figure 7 shows the state in which a removable restraint 70 is attached to the cryopump 10. Similar to the embodiment described above, the restraint 70 connects the cryogenic refrigerator 14 to the cryopump vacuum vessel 12 in parallel with the vibration isolation structure 16, and restrains both the extension and contraction of the vibration isolation structure 16 between the cryogenic refrigerator 14 and the cryopump vacuum vessel 12.

[0078] The cryopump 10 is provided with a first mounting portion 72 formed on the cryopump vacuum vessel 12 and a second mounting portion 74 formed on the cryogenic refrigerator 14. In this embodiment, the first mounting portion 72 is formed on the vacuum vessel flange 24, and the second mounting portion 74 is formed on the outer circumferential surface of the refrigerator flange 26.

[0079] The restraint 70 comprises a first restraint member 81 and a second restraint member 82. The first restraint member 81 is attached to the first mounting portion 72 at one end and to the second mounting portion 74 at the other end, and restrains the extension of the vibration damping structure 16. The first restraint member 81 may be, for example, a rod, or a bolt. The second restraint member 82 is positioned along the first restraint member 81 between the first mounting portion 72 and the second mounting portion 74, and restrains the contraction of the vibration damping structure 16. For example, the second restraint member 82 may be a cylinder through which the first restraint member 81 can be inserted. Similar to the embodiments described above, the first restraint member 81 and the second restraint member 82 are formed of a highly rigid material, such as a metal material (e.g., stainless steel).

[0080] The first mounting portion 72 may include a first lug portion 83 formed on the vacuum vessel flange 24, and the second mounting portion 74 may include a second lug portion 84 formed on the refrigerator flange 26. The first lug portion 83 is a projection that protrudes radially outward from the outer circumference of the vacuum vessel flange 24 and has a hole (e.g., a bolt hole) for receiving the first restraint member 81. Similarly, the second lug portion 84 is a projection that protrudes radially outward from the outer circumference of the refrigerator flange 26 and has a hole (e.g., a bolt hole) for receiving the first restraint member 81.

[0081] The first lugs 83 are formed at multiple locations (for example, at least three) in the circumferential direction on the outer surface of the vacuum vessel flange 24. Similarly, the second lugs 84 are formed at multiple locations (for example, at least three) in the circumferential direction on the outer surface of the refrigerator flange 26. In this example, four first lugs 83 are formed at equal intervals in the circumferential direction on the outer surface of the vacuum vessel flange 24, and four second lugs 84 are formed at equal intervals in the circumferential direction on the outer surface of the refrigerator flange 26. The second lugs 84 are formed on the outer surface of the refrigerator flange 26 in an arrangement corresponding to the first lugs 83 (i.e., at the same circumferential positions as the first lugs 83).

[0082] Furthermore, the first mounting portion 72 may be formed at the end of the vibration-damping structure 16 on the cryopump vacuum vessel 12 side, and the second mounting portion 74 may be formed at the end of the vibration-damping structure 16 on the cryogenic refrigerator 14 side. In the above embodiment, the first flange 28 of the vibration-damping structure 16 is fixed to the vacuum vessel flange 24, and the second flange 30 of the vibration-damping structure 16 is fixed to the refrigerator flange 26. Therefore, the first lug portion 83 may be formed on the first flange 28 of the vibration-damping structure 16. Similarly, the second lug portion 84 may be formed on the second flange 30 of the vibration-damping structure 16.

[0083] The restraint device 70 is attached to the first mounting portion 72 at one end and to the second mounting portion 74 at the other end. For example, if the first restraint member 81 is a bolt, the first restraint member 81 is first inserted into the bolt hole of the first lug portion 83 and into the second restraint member 82. At this time, the second restraint member 82 is positioned between the first lug portion 83 and the second lug portion 84, that is, on the opposite side of the bolt head of the first restraint member 81 from the first lug portion 83. Next, the tip of the first restraint member 81 is inserted into the bolt hole of the second lug portion 84, and the first restraint member 81 is fixed to the second lug portion 84 using a nut 85. Note that the second lug portion 84 may have a bolt hole into which the first restraint member 81 is screwed, in which case the tip of the first restraint member 81 is directly fixed to the second lug portion 84, so it is not necessary to use a nut 85.

[0084] The restraint 70 attached to the cryopump 10 extends along the vibration-damping structure 16 from the first mounting portion 72 to the second mounting portion 74, bridging both ends of the vibration-damping structure 16. The first restraint member 81 engages with the first ear portion 83 and the second ear portion 84 on both outer sides, thereby restraining the extension of the vibration-damping structure 16. The axial length of the second restraint member 82 is equal to the distance between the first ear portion 83 and the second ear portion 84. Since the second restraint member 82 is inserted through the first restraint member 81 and sandwiched between the first ear portion 83 and the second ear portion 84, it can restrain the contraction of the vibration-damping structure 16.

[0085] In this way, the restraint 70 can restrain both the extension and contraction of the vibration isolation structure 16, thereby restraining the movement of the cryogenic refrigerator 14 relative to the cryopump vacuum vessel 12. This reduces the risk of deformation of the vibration isolation structure 16 due to unexpected loads or impacts that may act on the cryopump 10 during transport, and the resulting damage to the inside of the cryopump 10, thereby protecting the cryopump 10.

[0086] If space for the first mounting portion 72 and the second mounting portion 74 is secured on the vacuum container flange 24 and the refrigerator flange 26, the first lug portion 83 and the second lug portion 84 do not need to be provided. In this case, holes through which the first restraining member 81 is inserted may be provided in the vacuum container flange 24 and the refrigerator flange 26.

[0087] Figure 8 is a schematic diagram showing a part of the cryopump 10 according to an embodiment. The first mounting portion 72 may include a first mounting block 86 instead of the first lug portion 83 described above. The second mounting portion 74 may include a second mounting block 87 instead of the second lug portion 84. The first mounting block 86 is attached to the vacuum vessel flange 24 by mounting members such as bolts. In this case, existing bolt holes on the vacuum vessel flange 24 may be used. The first mounting block 86 has through holes for the first restraint member 81, similar to the first lug portion 83. Similarly, the second mounting block 87 is attached to the refrigerator flange 26 by mounting members such as bolts. In this case, existing bolt holes on the refrigerator flange 26 may be used. The second mounting block 87 has through holes for the first restraint member 81, similar to the second lug portion 84.

[0088] The first restraining member 81 is inserted into the through hole of the first mounting block 86 and into the second restraining member 82. At this time, the second restraining member 82 is positioned between the first mounting block 86 and the second mounting block 87. Next, the tip of the first restraining member 81 is inserted into the through hole of the second mounting block 87, and the first restraining member 81 is fixed to the second mounting block 87 using a nut 85. Note that the second mounting block 87 may have a bolt hole into which the first restraining member 81 is screwed. In this case, the tip of the first restraining member 81 is directly fixed to the second mounting block 87, so it is not necessary to use a nut 85.

[0089] In the embodiment shown in Figure 8, as in the embodiment shown in Figure 7, the restraint 70 can restrain both the extension and contraction of the vibration isolation structure 16, thereby restraining the movement of the cryogenic refrigerator 14 relative to the cryopump vacuum vessel 12. This reduces the risk of deformation of the vibration isolation structure 16 due to unexpected loads or impacts that may act on the cryopump 10 during transport, and the resulting damage to the inside of the cryopump 10, thereby protecting the cryopump 10.

[0090] Figure 9(a) is a flowchart showing an example of a cryopump manufacturing method according to the embodiment, and Figure 9(b) is a flowchart showing an example of a cryopump usage method according to the embodiment.

[0091] As shown in Figure 9(a), the cryopump manufacturing method comprises preparing a cryopump 10 (S10) and attaching a removable restraint 70 to the cryopump 10 (S20). For example, a cryopump 10 without the restraint 70 attached, as described with reference to Figure 1, is prepared. The removable restraint 70 connects the cryogenic refrigerator 14 in parallel with the vibration isolation structure 16 to the cryopump vacuum vessel 12, as illustrated with reference to Figures 6 to 8, and restrains both the extension and contraction of the vibration isolation structure 16 between the cryogenic refrigerator 14 and the cryopump vacuum vessel 12. The attachment of the restraint 70 (S20) may be performed as one of the final steps in the manufacturing of the cryopump 10, for example, before the cryopump 10 is shipped. This method may further comprise packaging the cryopump 10 with the restraint 70 attached in packaging material.

[0092] In this way, the restraint device 70 restricts the movement of the cryogenic refrigerator 14 relative to the cryopump vacuum vessel 12, reducing the risk of deformation of the vibration isolation structure 16 due to unexpected loads or impacts and the resulting damage inside the cryopump 10, thereby protecting the cryopump 10.

[0093] As shown in Figure 9(b), the method of using the cryopump comprises preparing a cryopump 10 to which a removable restraint 70 is attached (S30), and removing the removable restraint 70 from the cryopump 10 (S40). For example, in the embodiment of Figure 6, the restraint 70 can be removed from the cryopump 10 by removing the first mounting member 76a and the second mounting member 76b from the first mounting part 72 and the second mounting part 74, respectively. In the embodiments of Figures 7 and 8, the restraint 70 can be removed from the cryopump 10 by removing the nut 85. By removing the restraint 70 in this way, the vibration isolation structure 16 is freed from the restraint 70. The vibration isolation structure 16 can provide vibration isolation when the cryopump 10 is used on-site, that is, when it is installed in a vacuum process apparatus and the apparatus is evacuated by vacuum.

[0094] The present invention has been described above based on examples. Those skilled in the art will understand that the present invention is not limited to the above embodiments, that various design changes are possible, and that various modifications are possible, and that such modifications also fall within the scope of the present invention. Various features described in relation to one embodiment are applicable to other embodiments. New embodiments resulting from combinations will possess the combined effects of each of the embodiments combined.

[0095] In the above-described embodiment, the case in which the vibration isolation structure 16 has a specific form, namely, the case in which the first annular vibration isolation material 38, the first annular support member 40, the intermediate annular vibration isolation material 42, the second annular support member 44, and the second annular vibration isolation material 46 are arranged in the order described above from the first flange 28 toward the second flange 30 to form an annular laminated vibration isolation body 32, is described as an example. However, the restraint device 70 according to the embodiment is also applicable to other vibration isolation structures that can be mounted on the cryopump 10. The vibration isolation structure of the cryopump 10 combined with the restraint device 70 may have a simpler form. For example, the two flanges may be fixed to each other by sandwiching a vibration isolation material such as vibration isolation rubber between the vacuum vessel flange 24 of the cryopump vacuum vessel 12 and the first flange 28 of the cryogenic refrigerator 14.

[0096] Although the present invention has been described using specific terms based on the embodiments, the embodiments only illustrate one aspect of the principle and application of the present invention, and many modifications and changes in arrangement are permitted in the embodiments, as long as they do not depart from the spirit of the present invention as defined in the claims. [Explanation of Symbols]

[0097] 10 Cryopump, 12 Cryopump vacuum vessel, 14 Cryogenic refrigerator, 16 Vibration isolation structure, 24 Vacuum vessel flange, 26 Refrigerator flange, 28 First flange, 30 Second flange, 32 Annular laminated vibration isolation body, 38 First annular vibration isolation material, 40 First annular support member, 42 Intermediate annular vibration isolation material, 44 Second annular support member, 46 Second annular vibration isolation material, 70 Restraint, 72 First mounting part, 74 Second mounting part, 81 First restraint member, 82 Second restraint member, 83 First lug, 84 Second lug.

Claims

1. Cryogenic refrigerator and Cryopump vacuum vessel and A vibration-damping structure for connecting the cryogenic refrigerator to the cryopump vacuum vessel, The cryogenic refrigerator is connected to the cryopump vacuum vessel in parallel with the vibration-damping structure, and a removable restraining plate is provided to restrain both the extension and contraction of the vibration-damping structure between the cryogenic refrigerator and the cryopump vacuum vessel. A first seating surface is formed on the cryopump vacuum vessel, or on the end of the vibration-damping structure on the cryopump vacuum vessel side, and has a shape that matches the shape of the restraint plate, The cryogenic refrigerator, or the end of the vibration-damping structure on the cryogenic refrigerator side, comprises a second seating surface having a shape that matches the shape of the restraining plate, The cryopump is characterized in that the restraint plate is fixed to the first seat surface by a first mounting member and to the second seat surface by a second mounting member.

2. The restraint plate has a first through hole at one end and a second through hole at the other end, The first seating surface has a first screw hole, and the second seating surface has a second screw hole. The cryopump according to claim 1, characterized in that the restraint plate is fixed to the first seating surface by attaching the first mounting member to the first screw hole through the first through hole, and the second mounting member is fixed to the second seating surface by attaching the second mounting member to the second screw hole through the second through hole.

3. The cryopump vacuum vessel is equipped with a vacuum vessel flange, The cryogenic refrigerator is equipped with a refrigerator flange, The vibration isolation structure comprises a first flange fixed to the vacuum vessel flange and a second flange fixed to the refrigerator flange. The cryopump according to claim 1, characterized in that the first seating surface is formed on the vacuum vessel flange or the outer circumferential surface of the first flange, and the second seating surface is formed on the outer circumferential surface of the refrigerator flange or the second flange.

4. The first seating surface is formed as a flush, flat surface extending across the vacuum vessel flange and the outer circumferential surface of the first flange, The cryopump according to claim 3, characterized in that the second seating surface is formed as a flat surface flush with the refrigeration flange and the outer circumferential surface of the second flange.

5. The vibration-damping structure comprises a vibration-damping material, The cryopump according to claim 1, characterized in that the restraining plate has a Young's modulus greater than that of the vibration-damping material in the direction of expansion and contraction of the vibration-damping structure.

6. The aforementioned vibration isolation structure is A first flange fixed to the cryopump vacuum vessel, A second flange is fixed to the cryogenic refrigerator and is airtightly connected to the first flange, The device comprises an annular laminated vibration damper in which a first annular vibration damping material, a first annular support member, an intermediate annular vibration damping material, a second annular support member, and a second annular vibration damping material are arranged in the order described herein, from the first flange toward the second flange. The cryopump according to claim 1, characterized in that the second annular support member is fixed to the first flange and the first annular support member is fixed to the second flange so that the first flange and the second annular support member are vibrationally insulated from the second flange and the first annular support member.

7. Cryogenic refrigerator and Cryopump vacuum vessel and A vibration-damping structure for connecting the cryogenic refrigerator to the cryopump vacuum vessel, A first seating surface formed on the cryopump vacuum vessel or on the end of the vibration-damping structure on the cryopump vacuum vessel side, wherein a restraining plate can be attached by a first mounting member, and the first seating surface has a shape that matches the shape of the restraining plate, A cryopump characterized by comprising: a second seating surface formed on the cryogenic refrigerator or on the end of the vibration-damping structure on the cryogenic refrigerator side, wherein the restraining plate can be attached by a second mounting member, and the second seating surface has a shape that matches the shape of the restraining plate.

8. Prepare a cryopump, The system includes attaching a removable restraint plate to the cryopump, The cryopump comprises a cryogenic refrigerator, a cryopump vacuum vessel, a vibration-damping structure connecting the cryogenic refrigerator to the cryopump vacuum vessel, a first seating surface formed on the cryopump vacuum vessel or at the end of the vibration-damping structure on the cryopump vacuum vessel side and having a shape that matches the shape of the restraint plate, and a second seating surface formed on the cryogenic refrigerator or at the end of the vibration-damping structure on the cryogenic refrigerator side and having a shape that matches the shape of the restraint plate. A method for manufacturing a cryopump, characterized in that the removable restraint plate is fixed to the first seat surface by a first mounting member and to the second seat surface by a second mounting member, thereby connecting the cryogenic refrigerator to the cryopump vacuum vessel in parallel with the vibration-damping structure, and restraining both the extension and contraction of the vibration-damping structure between the cryogenic refrigerator and the cryopump vacuum vessel.

9. Prepare a cryopump with a removable restraint plate, The removable restraint plate is removed from the cryopump, The cryopump comprises a cryogenic refrigerator, a cryopump vacuum vessel, a vibration-damping structure connecting the cryogenic refrigerator to the cryopump vacuum vessel, a first seating surface formed on the cryopump vacuum vessel or at the end of the vibration-damping structure on the cryopump vacuum vessel side and having a shape that matches the shape of the restraint plate, and a second seating surface formed on the cryogenic refrigerator or at the end of the vibration-damping structure on the cryogenic refrigerator side and having a shape that matches the shape of the restraint plate. A method for using a cryopump, characterized in that the removable restraint plate is fixed to the first seat surface by a first mounting member and to the second seat surface by a second mounting member, thereby connecting the cryogenic refrigerator to the cryopump vacuum vessel in parallel with the vibration-damping structure, and restraining both the extension and contraction of the vibration-damping structure between the cryogenic refrigerator and the cryopump vacuum vessel.

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