Scanning electron microscope

Abstract

The invention relates to the technical field of scanning electron microscopes, in particular to a scanning electron microscope which comprises a mounting frame, an electron microscope body, a vacuumizing mechanism, an adapter, a damping mechanism and a vacuum tube structure, the electron microscope body comprises a lens cone and a sample bin, and the vacuumizing mechanism is used for synchronously vacuumizing the lens cone and the sample bin; the damping mechanism is arranged between the mounting rack and the electron microscope main body; the adapter comprises an adapter tube, a first joint and a second joint, and the first joint and the second joint are arranged on the two sides of the adapter tube; the vacuum tube structure comprises a first flexible tube, a first rigid tube, a second flexible tube and a second rigid tube, and the first flexible tube and the second flexible tube are symmetrically arranged. Due to the fact that the flexible pipes are connected with the vacuumizing mechanism and the rigid pipe is connected with the electron microscope body, the symmetrical flexible pipes can balance pulling force in the vacuumizing process, the influence of the pulling force on the electron microscope body is reduced, the influence on the image quality is reduced, and the detection accuracy of the scanning electron microscope and the definition of images are effectively guaranteed.

Description

Technical Field

[0001] The present application relates to the technical field of scanning electron microscopes, and more specifically to a scanning electron microscope. Background Art

[0002] Scanning electron microscopy (SEM) is an observation technique intermediate between transmission electron microscopy and optical microscopy. It uses a narrowly focused high-energy electron beam to scan a sample. The interaction between the beam and the material stimulates various physical information, which is then collected, amplified, and re-imaged to characterize the material's microscopic morphology. Combining SEM with other analytical instruments allows for simultaneous observation of microscopic morphology and analysis of micro-area composition. SEMs are also widely used in the study of geotechnical materials, graphite, ceramics, and nanomaterials, thus playing a significant role in scientific research.

[0003] When a scanning electron microscope is conducting sample testing, it is necessary to use a vacuum pump to evacuate the sample chamber. However, after evacuation, it is found that the imaging quality of the scanning electron microscope is poor. Summary of the Invention

[0004] The present application provides a scanning electron microscope that can at least partially solve or improve the above problems.

[0005] The present application provides a scanning electron microscope, comprising: Mounting rack; An electron microscope body, the electron microscope body being arranged in the mounting frame; the electron microscope body comprising a lens barrel and a sample chamber, the lens barrel and the sample chamber being in communication; the lens barrel being provided with a first connection port, the sample chamber being provided with a second connection port; A vibration reduction mechanism, the vibration reduction mechanism being arranged between the mounting frame and the electron microscope body; A vacuum pumping mechanism, the vacuum pumping mechanism being disposed in the mounting frame; the vacuum pumping mechanism being used to simultaneously vacuum the lens barrel and the sample chamber; the vacuum pumping mechanism being provided with a third connection port; an adapter, the adapter comprising an adapter tube, a first connector, and a second connector, the adapter tube being connected to the third connection port, the first connector and the second connector being disposed on both sides of the adapter tube; and A vacuum tube structure, the vacuum tube structure comprising a first flexible tube, a first rigid tube, a second flexible tube, and a second rigid tube, the first flexible tube and the first rigid tube being in communication with each other, one end of the first flexible tube away from the first rigid tube being connected to the first joint to be in communication with the vacuum pumping mechanism via the first joint, and one end of the first rigid tube away from the first flexible tube being connected to the first connecting port to be in communication with the lens barrel via the first connecting port; the second flexible tube and the second rigid tube being in communication, one end of the second flexible tube away from the second rigid tube being connected to the second joint to be in communication with the vacuum pumping mechanism via the second joint, and one end of the second rigid tube away from the second flexible tube being connected to the second connecting port to be in communication with the sample chamber via the second connecting port; The first joint and the second joint are symmetrically arranged on the transition tube along the central axis of the transition tube; the first flexible tube and the second flexible tube are symmetrically arranged along the central axis of the transition tube.

[0006] In some optional embodiments, the first rigid tube and the second rigid tube are arranged in parallel.

[0007] In some optional embodiments, the first rigid tube and the first flexible tube are perpendicular to each other; the second flexible tube and the second rigid tube are perpendicular to each other.

[0008] In some embodiments, the first rigid tube is placed horizontally and the first flexible tube is placed vertically.

[0009] In some optional embodiments, the vacuum tube structure also includes a first connecting structure, a second connecting structure, a third connecting structure and a fourth connecting structure, wherein the first connecting structure is used to seal and fix the first joint and the first flexible tube; the second connecting structure is used to seal and fix the first flexible tube and the first rigid tube; the third connecting structure is used to seal and fix the second joint and the second flexible tube; and the fourth connecting structure is used to seal and fix the second flexible tube and the second rigid tube.

[0010] In some optional embodiments, the first connecting structure, the second connecting structure, the third connecting structure and the fourth connecting structure all include a clamp, and the clamp includes an annular body, a fastening bolt and a sealing gasket, the sealing gasket is fitted to the inner wall of the annular body, and the fastening bolt is passed through the open end of the annular body for adjusting the radial size of the annular body.

[0011] In some optional embodiments, the first flexible tube and the second flexible tube are made of corrugated tubes.

[0012] In some optional embodiments, the mounting frame includes a bottom bracket and a side bracket, the bottom bracket and the side bracket enclose a storage space, the electron microscope body and the vacuum pumping mechanism are both arranged in the storage space, and the sample chamber is arranged on the bottom bracket, and the lens barrel is arranged on the sample chamber; the vibration damping mechanism is arranged between the sample chamber and the bottom bracket.

[0013] In some optional embodiments, the vibration reduction mechanism includes a first support member, a second support member, a buffer pad and an elastic member, the first support member is connected to the sample chamber, the second support member is connected to the bottom bracket, the buffer pad is arranged between the first support member and the second support member, and the elastic member is arranged on the outside of the buffer pad.

[0014] In some optional embodiments, a receiving groove is provided on the second support member, and at least part of the buffer pad and the elastic member are arranged in the receiving groove; a fixing hole is provided on the second support member, and the fixing hole is used to install a fixing member so that the second support member is fixed to the bottom bracket.

[0015] According to the scanning electron microscope in this embodiment, it includes a mounting frame, an electron microscope body, a vacuum pumping mechanism, an adapter, a vibration damping mechanism and a vacuum tube structure. The flexible tube in the vacuum tube structure is connected to the vacuum pumping mechanism through the adapter, and the rigid tube is connected to the electron microscope body. The first flexible tube and the second flexible tube are arranged symmetrically so that the flexible tube can balance the tension applied to the vacuum tube structure during the vacuum pumping process, thereby reducing the impact of the tension on the electron microscope body, thereby reducing the impact on the image quality, and effectively ensuring the accuracy of the scanning electron microscope detection and the clarity of the image. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic structural diagram of a scanning electron microscope in an embodiment; Figure 2 A schematic diagram of the force acting on a scanning electron microscope in one embodiment; Figure 3 A schematic diagram of the connection between the vacuum tube structure and the adapter in one embodiment; Figure 4 This is a structural diagram of a first connection structure in an embodiment; Figure 5 is a schematic structural diagram of a first flexible tube in an embodiment; Figure 6 This is a schematic diagram of the structure of a scanning electron microscope after removing some components in an embodiment; Figure 7 A schematic structural diagram of a vibration reduction mechanism in one embodiment; Figure 8 This is a schematic structural diagram of an elastic member in an embodiment; Figure 9 Schematic diagram of the structure of some components of the vibration reduction mechanism in one embodiment.

[0017] Among them: 1. Scanning electron microscope; 10. Electron microscope body; 11. Lens tube; 111. First connection port; 12. Sample chamber; 121. Second connection port; 20. Vacuum pumping mechanism; 21. Third connection port; 30. Adapter; 31. Adapter tube; 32. First connector; 33. Second connector; 40. Vacuum tube structure; 41. First flexible tube; 411. Telescopic section; 412. First connecting flange; 413. Second connecting flange; 414. First mounting slot; 415. Second mounting slot; 42. First rigid tube; 43. Second flexible tube; 44. Second rigid tube; 45. First connecting structure; 451. Annular body; 4511. First hoop; 4512. Second hoop; 452. Fastening bolt; 46. Second connecting structure; 47. Third connecting structure; 48. Fourth connecting structure; 50. Mounting frame; 51. Bottom bracket; 511. Hollow structure; 5111. Partition; 5112. Reinforcement rib; 52. Side bracket; 53. Accommodation space; 60. Vibration reduction mechanism; 61. First support member; 62. Second support member; 621. Accommodation groove; 63. Buffer pad; 64. Elastic member; X, first direction; Y, second direction. DETAILED DESCRIPTION

[0018] The present application is further described in detail below by means of specific embodiments in conjunction with the accompanying drawings. Similar elements in different embodiments are numbered with associated similar elements. In the following embodiments, many detailed descriptions are provided to enable the present application to be better understood. However, those skilled in the art will readily appreciate that some of the features may be omitted in different circumstances, or may be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification. This is to avoid the core portion of the present application being overwhelmed by excessive descriptions. For those skilled in the art, it is not necessary to describe these related operations in detail. They can fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0019] In addition, the features, operations, or characteristics described in the specification may be combined in any appropriate manner to form various implementations, and the operational steps involved in each embodiment may be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the specification and drawings are only for the purpose of clearly describing a particular embodiment and do not imply a required composition and / or sequence.

[0020] Component numbers used herein, such as "first" and "second," are used solely to distinguish the components being described and do not convey any sequential or technical meaning. References to "connection" and "coupling" herein, unless otherwise specified, include both direct and indirect connections (couplings).

[0021] The scanning electron microscope (SEM), also known as SEM1, is an observation method intermediate between the transmission electron microscope and the optical microscope. It is a large, precision instrument used for high-resolution micro-area morphological analysis. It features a large depth of field, high resolution, intuitive imaging, a strong three-dimensional effect, a wide range of magnification factors, and the ability to rotate and tilt the sample in three dimensions. It uses a narrowly focused high-energy electron beam to scan the sample. The interaction between the beam and the material stimulates various physical information, which is then collected, amplified, and re-imaged to characterize the material's microscopic morphology. When combined with other analytical instruments, the SEM1 can simultaneously observe microscopic morphology and analyze the composition of a material at a microscopic level. It also offers the advantages of being able to measure a wide variety of samples, virtually avoiding damage or contamination to the original sample, and simultaneously obtaining information on morphology, structure, composition, and crystallography. At present, scanning electron microscopes have been widely used in microscopic research in the fields of life sciences, physics, chemistry, justice, earth sciences, materials science, and industrial production. In the field of earth sciences alone, it includes crystallography, mineralogy, ore deposits, sedimentology, geochemistry, gemology, micropaleontology, astrogeology, oil and gas geology, engineering geology, and structural geology.

[0022] The basic structure of the scanning electron microscope 1 includes an electron microscope body 10, a detection system, and an imaging system. The electron microscope body 10 includes an electron optical system (tube 11) for forming a high-energy electron beam and emitting it to the sample, and also includes a sample chamber 12 for placing the sample. The detection system is used to collect reflected or transmitted electrons, and the imaging system forms an image based on the detection information of the detection system.

[0023] In the related art, to ensure scanning accuracy, after pulling out the door of the sample chamber 12, placing the sample on the sample stage, and then closing the door of the sample chamber 12, it is necessary to evacuate the sample chamber 12. Therefore, the scanning electron microscope 1 also includes a vacuuming mechanism 20 (e.g., a vacuum pump). Some scanning electron microscopes 1 also have multiple vacuuming mechanisms 20 (e.g., vacuum pumps) to achieve different vacuum levels. However, the inventors have discovered that during the vacuuming process, the vacuuming mechanism 20 (e.g., a vacuum pump) will vibrate, and the vibration will reach the electron microscope body 10 along the vacuum pipe, causing the sample chamber 12 or the lens barrel 11 to shake, thereby affecting the imaging quality of the scanning electron microscope 1. In addition, in order to improve the vibration reduction performance of the scanning electron microscope 1 against external environmental vibrations, the electron microscope body 10 of the scanning electron microscope 1 is generally disposed on an elastic vibration reduction mechanism 60 (capable of appropriate elastic deformation) so that the electron microscope body 10 has a certain amount of movable margin. During the evacuation process, because the air pressure within the vacuum tube is much lower than atmospheric pressure, the flexible tubes within the vacuum tube tend to move closer together at atmospheric pressure. This creates tension between the rigid vacuum tube and the electron microscope body 10. Consequently, the electron microscope body 10 may tilt under this tension. This unintended tilt may cause air leaks in the lens barrel 11 or electron beam deviation, impacting the sealing performance and imaging quality of the electron microscope body 10. The presence of the vibration damping mechanism 60 exacerbates this tilting phenomenon, particularly when the vibration damping mechanism 60 includes multiple or multiple vibration damping components (or a composite vibration damping mechanism) to accommodate vibrations of varying frequencies.

[0024] The combined effects of the vibration of the vacuum pumping mechanism 20 during the vacuuming process, the tension generated by the pressure difference between the inside and outside of the vacuum tube, and the vibration reduction mechanism 60 greatly reduce the image quality and airtightness of the scanning electron microscope 1.

[0025] In order to overcome or improve the above-mentioned problems, the present application proposes a scanning electron microscope 1, and creatively improves its vacuum tube structure 40, thereby overcoming the influence of the tension generated between the vacuum mechanism 20 and the electron microscope body 10 due to the pressure difference between the atmospheric pressure and the air pressure in the vacuum tube structure 40 during the vacuuming process on the imaging quality, and also overcoming the influence of the vibration of the vacuum mechanism 20.

[0026] See also Figures 1 to 9 The scanning electron microscope 1 includes an electron microscope body 10, a vacuum pumping mechanism 20, an adapter 30 and a vacuum tube structure 40. The electron microscope body 10 includes a lens barrel 11 and a sample chamber 12. The vacuum tube structure 40 is arranged between the vacuum pumping mechanism 20 and the lens barrel 11 and the sample chamber 12 to vacuum the lens barrel 11 and the sample chamber 12 to ensure that the vacuum degree in the lens barrel 11 and the sample chamber 12 meets the requirements.

[0027] The lens barrel 11 is connected to the sample chamber 12 and is used to form a high-energy electron beam and emit it to the sample in the sample chamber 12. The lens barrel 11 is provided with a first connecting port 111, which is used to connect to the vacuum pumping mechanism 20 through the vacuum tube structure 40.

[0028] The sample chamber 12 has a sample table for placing samples. The sample chamber 12 has a chamber door so that the operator can take and place samples through the chamber door. The sample chamber 12 is provided with a second connection port 121 for connecting to the vacuum mechanism 20 through the vacuum tube structure 40 .

[0029] The vacuum pumping mechanism 20 includes a vacuum pump, which is provided with a third connection port 21. The adapter 30 includes an adapter tube 31, a first connector 32, and a second connector 33. The adapter tube 31 is connected to the third connection port 21, and the first connector 32 and the second connector 33 are provided on both sides of the adapter tube 31. It can also be understood that the adapter 30 is a three-way structure with three connectors, one of which is connected to the third connection port 21 on the vacuum pumping mechanism 20, and the other two connectors are respectively connected to the lens barrel 11 and the sample chamber 12 through the vacuum tube structure 40 to achieve vacuuming of the lens barrel 11 and the sample chamber 12. In some application scenarios, the lens barrel 11 and the sample chamber 12 can be vacuumed simultaneously.

[0030] The scanning electron microscope 1 also includes a mounting frame 50 and a vibration reduction mechanism 60. The electron microscope body 10 and the vacuum pumping mechanism 20 are both arranged in the mounting frame 50, and the vibration reduction mechanism 60 is arranged between the electron microscope body 10 and the mounting frame 50 to buffer the impact force applied to the scanning electron microscope 1 by vibrations in the external environment during the operation of the scanning electron microscope 1 and during movement and transportation, thereby ensuring the clarity of imaging and the accuracy of detection of the scanning electron microscope 1.

[0031] See also Figure 2 The vacuum tube structure 40 includes a first flexible tube 41, a first rigid tube 42, a second flexible tube 43 and a second rigid tube 44. The first flexible tube 41 and the first rigid tube 42 are connected to each other. The end of the first flexible tube 41 away from the first rigid tube 42 is connected to the first joint 32 to communicate with the vacuum pumping mechanism 20 through the first joint 32. The end of the first rigid tube 42 away from the first flexible tube 41 is connected to the first connecting port 111 to communicate with the lens barrel 11 through the first connecting port 111; the second flexible tube 43 and the second rigid tube 44 are connected. The end of the second flexible tube 43 away from the second rigid tube 44 is connected to the second joint 33 to communicate with the vacuum pumping mechanism 20 through the second joint 33. The end of the second rigid tube 44 away from the second flexible tube 43 is connected to the second connecting port 121 to communicate with the sample chamber 12 through the second connecting port 121.

[0032] Arranging the vacuum tube structure 40 connected to the adapter 30 as a flexible tube can also be understood as arranging the vacuum tube structure 40 on the side close to the vacuum pumping mechanism 20 as a flexible tube to buffer the impact of the vibration generated by the vacuum pumping mechanism 20 during the vacuuming process on the electron microscope body 10. However, the applicant creatively discovered that during the vacuuming process, because the air pressure in the vacuum tube structure 40 is much lower than the atmospheric pressure, the two sides of the flexible tube tend to move closer to each other, that is, there is a tensile force between the adapter 30 and the electron microscope body 10, such as Figure 2 As indicated by the middle arrow, this pulling force causes the microscope body 10 to tilt. Because the microscope body 10 is mounted on the mounting frame 50 via a vibration damping mechanism 60, it has a certain amount of play, which exacerbates the tilting. To address this, a first flexible tube 41 and a second flexible tube 43 are provided on either side of the adapter 30. The pulling forces exerted by these tubes are at least partially in opposite directions, at least partially balancing the pulling force applied to the microscope body 10. This reduces the effect of the pulling force on the microscope body 10 caused by the pressure difference between the inside and outside of the microscope during vacuuming, thereby minimizing the impact on image quality. At the same time, the first flexible tube 41 and the second flexible tube 43 are close to the vacuum pumping mechanism 20, which can further enhance the vibration isolation and vibration reduction effect between the electron microscope body 10 and the vacuum pumping mechanism 20. The first rigid tube 42 and the second rigid tube 44 are respectively arranged close to the lens barrel 11 and the sample chamber 12. Since the rigid tube itself has a fixed shape and high strength, the docking accuracy with the first connection port 111 and the second connection port 121 is higher, which can reduce the risk of leakage caused by pipeline deformation or vibration, and can reduce the resistance during the flow of airflow, so as to improve the efficiency and uniformity of vacuuming, and can further effectively reduce the impact on image quality.

[0033] In some embodiments, the first connector 32 and the second connector 33 are symmetrically arranged on the transfer tube 31 along the central axis of the transfer tube 31. This can also be understood as the first flexible tube 41 and the second flexible tube 43 being symmetrically arranged on both sides of the transfer tube 31. The pressure difference and gas flow rate of the first flexible tube 41 and the second flexible tube 43 are symmetrical, and the pulling forces on both sides are equal in magnitude and opposite in direction, which can offset the two pulling forces, thereby making the entire vacuum tube structure 40 balanced in force and preventing forces that cause the electron microscope body 10 to tilt. In addition, the symmetrical arrangement of the first connector 32 and the second connector 33 also ensures that the flow resistance of the airflow in the vacuum tube structure 40 connecting the lens barrel 11 and the sample chamber 12 is the same, which can ensure that the pumping rates of the lens barrel 11 and the sample chamber 12 are synchronized, avoid local pressure imbalance caused by resistance differences, and thus ensure the stability of electron beam transmission and sample imaging.

[0034] In some embodiments, the first connector 32 and the second connector 33 are constructed as an integrally formed structure with the adapter tube 31, which reduces the assembly process between parts and can also improve the overall integrity and sealing of the adapter 30, thereby further effectively ensuring the efficiency and effect of vacuuming.

[0035] In some embodiments, the first rigid tube 42 and the second rigid tube 44 are arranged in parallel. In some application scenarios, the electron microscope body 10 and the vacuum pumping mechanism 20 are both placed vertically within the mounting frame 50, and the lens barrel 11 is placed vertically above the sample chamber 12. The first rigid tube 42 and the second rigid tube 44 are placed horizontally (parallel to the horizontal plane), with the first rigid tube 42 positioned above the second rigid tube 44 to match the layout of the lens barrel 11 and the sample chamber 12. The first rigid tube 42 and the second rigid tube 44 of the rigid structure are placed horizontally, and their extension direction is consistent with the direction of airflow. The upward or downward forces exerted on the rigid tubes by the pressure difference can offset each other, and no tilting pull is generated on the electron microscope body 10, thereby effectively ensuring image quality. Moreover, no elbow or other transition structure is required between the lens barrel 11 and the first rigid tube 42, the sample chamber 12, and the second rigid tube 44, thereby reducing the impact of unnecessary transition structures on the vacuum effect.

[0036] In some embodiments, the first rigid tube 42 and the first flexible tube 41 are perpendicular to each other; the second flexible tube 43 and the second rigid tube 44 are perpendicular to each other. In some application scenarios, the first rigid tube 42 and the second rigid tube 44 are placed horizontally, while the first flexible tube 41 and the second flexible tube 43 are placed vertically. The extension direction of the first flexible tube 41 and the second flexible tube 43 are aligned with the flow direction of the airflow. The static tension generated by the pressure difference is in the vertical direction. Due to the high strength of the first rigid tube 42 and the second rigid tube 44, this static tension does not generate a force that tilts the electron microscope body 10, thereby preventing the electron microscope body 10 from affecting image quality.

[0037] See also Figure 3 In some embodiments, the vacuum tube structure 40 further includes a first connecting structure 45, a second connecting structure 46, a third connecting structure 47 and a fourth connecting structure 48. The first connecting structure 45 is used to seal and fix the first joint 32 and the first flexible tube 41; the second connecting structure 46 is used to seal and fix the first flexible tube 41 and the first rigid tube 42; the third connecting structure 47 is used to seal and fix the second joint 33 and the second flexible tube 43; the fourth connecting structure 48 is used to seal and fix the second flexible tube 43 and the second rigid tube 44. The first connecting structure 45, the second connecting structure 46, the third connecting structure 47 and the fourth connecting structure 48 help to improve the stability of the connection, and can further reduce the impact of airflow disturbances on the lens barrel 11 and the sample chamber 12, especially reduce the impact of uneven force caused by airflow disturbances on imaging quality.

[0038] In some embodiments, the first connection structure 45, the second connection structure 46, the third connection structure 47 and the fourth connection structure 48 all include a clamp, which includes an annular body 451, a fastening bolt 452 and a sealing gasket (not shown). The sealing gasket (not shown) is attached to the inner side wall of the annular body 451. The fastening bolt 452 is provided through the open end of the annular body 451 to adjust the radial size of the annular body 451. For example, please refer to Figure 4 The annular body 451 includes a first hoop 4511 and a second hoop 4512. One end of the first hoop 4511 and the second hoop 4512 are hingedly connected. The first hoop 4511 and the second hoop 4512 can form an annular structure with an opening. The annular structure can be clamped to the outer wall of a tubular structure, such as the outer wall of the first joint 32 and the first flexible tube 41, and then locked by the fastening bolt 452 at the open end. It should be noted that Figure 4 Although this is a schematic diagram of the first connection structure 45 , the structures of the second connection structure 46 , the third connection structure 47 and the fourth connection structure 48 are consistent with it, and their specific structures can also refer to this figure.

[0039] In some embodiments, the first flexible tube 41 and the second flexible tube 43 are constructed to be made of corrugated tubes. Figure 5 The bellows includes a telescopic section 411 and a first connecting flange 412 and a second connecting flange 413 arranged at both ends of the telescopic section 411. A first mounting groove 414 is provided between the first connecting flange 412 and the telescopic section 411, and a second mounting groove 415 is provided between the second connecting flange 413 and the telescopic section 411. The first connecting flange 412 is used to dock with the first joint 32 or the second joint 33, and the second connecting flange 413 is used to dock with the first rigid tube 42 or the second rigid tube 44. The first mounting groove 414 and the second mounting groove 415 are used to install the connecting structure. Exemplarily, the first connecting flange 412 of the first flexible tube 41 is connected to the first joint 32, and the first connecting structure 45 is sleeved on the outside of the first flexible tube 41 and the first joint 32, and partially locked in the first mounting groove 414, for achieving a sealed fixation between the first flexible tube 41 and the first joint 32. The first flexible tube 41 and the first rigid tube 42 are connected via the second connecting flange 413, and the second connecting structure 46 is sleeved on the outside of the first flexible tube 41 and the first rigid tube 42, and partially locked in the second mounting groove 415, for achieving a sealed fixation between the first flexible tube 41 and the first rigid tube 42. The sealed fixation of the second flexible tube 43, the second joint 33, and the second rigid tube 44 can refer to the above-mentioned method and will not be described in detail here.

[0040] In some embodiments, the bellows is made of stainless steel, and the corrugation pitch of the telescopic section 411 in the bellows is 1 mm-3 mm.

[0041] In some embodiments, third connecting flanges are provided at both ends of first rigid tube 42 and second rigid tube 44, and fourth connecting flanges are provided on first joint 32 and second joint 33. This ensures that first rigid tube 42 forms a stable and sealed connection with first connection port 111 and first flexible tube 41, respectively, via the third connecting flanges, and that second rigid tube 44 forms a stable and sealed connection with second connection port 121 and second flexible tube 43, respectively, via the fourth connecting flanges. The provision of first connecting flange 412, second connecting flange 413, third connecting flange, and fourth connecting flange simplifies the installation and disassembly process, improves connection stability, and prevents loose connections from affecting airtightness and, consequently, the accuracy of test results.

[0042] To further enhance the airtightness of the vacuum tube structure 40 during the evacuation process, a sealing ring is provided between the two butted connecting flanges. The sealing ring can be made of a metal ring. For example, a metal gasket is provided between the first connecting flange 412 and the fourth connecting flange, and between the second connecting flange 413 and the third connecting flange.

[0043] Please continue reading Figure 2 、 Figure 6 The mounting frame 50 includes a bottom bracket 51 and a side bracket 52. The bottom bracket 51 and the side bracket 52 enclose a storage space 53. The electron microscope body 10 and the vacuum pumping mechanism 20 are both disposed in the storage space 53. The sample chamber 12 is disposed on the bottom bracket 51, and the lens barrel 11 is disposed on the sample chamber 12. The storage space 53 can be a closed space or a semi-enclosed space. For example, the top of the mounting frame 50 may be open. Alternatively, the side bracket 52 and the bottom bracket 51 may be provided with openings (or gaps). These openings (or gaps) facilitate sample placement and removal and also provide heat dissipation.

[0044] In some embodiments, one of the side supports 52 of the mounting frame 50 can be movable relative to the adjacent side support 52 so as to expose the electron microscope body 10 and the vacuum pumping mechanism 20 in the accommodating space 53 from the side, thereby facilitating the placement and removal of samples in the sample chamber 12, as well as adjusting or repairing the electron microscope body 10 and the vacuum pumping mechanism 20.

[0045] See also Figure 6The bottom bracket 51 has a hollow structure 511, which is located below the vacuum mechanism 20 to dissipate heat from the vacuum mechanism 20. The hollow structure 511 includes a partition 5111 extending along a first direction X and a reinforcing rib 5112 extending along a second direction Y. Multiple partitions 5111 are arranged at intervals to form a heat dissipation gap, wherein the first direction X and the second direction Y are arranged at an angle. The provision of the reinforcing rib 5112 increases the connection between the multiple spaced partitions 5111, which helps to improve the strength of the hollow structure 511, effectively preventing vibration of the partition 5111, thereby reducing the impact of the vibration of the partition 5111 on the imaging quality of the electron microscope body 10. Exemplarily, the first direction X and the second direction Y are perpendicular to each other.

[0046] See also Figures 6 to 8 The vibration damping mechanism 60 includes a first support member 61, a second support member 62, a cushion 63, and an elastic member 64. The first support member 61 is connected to the sample chamber 12, and the second support member 62 is connected to the bottom bracket 51. The cushion 63 is disposed between the first support member 61 and the second support member 62, and the elastic member 64 is sleeved on the outside of the cushion 63. The cushion 63 is made of an elastic rubber pad. Specifically, the cushion 63 is constructed to include at least one of natural rubber (NR), butadiene rubber (BR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), ethylene-propylene rubber (EPR), polyurethane rubber (PU), silicone rubber, butyl rubber (HR), and nitrile rubber (NBR). Exemplarily, the cushion 63 is made of polyurethane rubber (UR), which has the advantages of good wear resistance, cushioning and vibration damping, oil resistance, drug resistance, low temperature resistance, ozone resistance, radiation resistance, electrical insulation, and good adhesion properties. Specifically, at room temperature, polyurethane rubber vibration damping elements can absorb 10%-20% of vibration energy. The higher the vibration frequency, the greater the energy absorption. Polyurethane rubber has a low affinity for non-polar mineral oil and is almost unaffected by fuel oil (such as kerosene, gasoline) and mechanical oil (such as hydraulic oil, engine oil, lubricating oil, etc.). It is much better than general-purpose rubber and comparable to nitrile rubber. In addition, the friction coefficient of polyurethane rubber is relatively high, generally above 0.5. Using polyurethane rubber to make the buffer pad 63 can effectively ensure the vibration reduction effect and service life.

[0047] In some embodiments, the cushion 63 is constructed as a truncated cone structure, and the elastic member 64 includes a spring, the size and shape of the spring matches the cushion 63 and is also constructed as a truncated cone (or pagoda). Figure 8 As shown, this type of spring has the characteristics of small size, large load and gradually changing stiffness, and is suitable for occasions with small space and large load.

[0048] In some embodiments, the first support member 61 can be a plate-like structure, which is arranged on both sides of the bottom of the sample chamber 12 and protrudes relative to the sample chamber 12. It can simultaneously buffer and isolate impact forces in the horizontal and vertical directions, thereby achieving an all-round and better buffering and vibration reduction effect.

[0049] In some embodiments, a receiving groove 621 is provided on the second support member 62 , and at least a portion of the buffer pad 63 and the elastic member 64 is disposed in the receiving groove 621 .

[0050] In some embodiments, the second support member 62 has a fixing hole that runs through from top to bottom, and the fixing hole is used to install a fixing member (screw, bolt or pin) to facilitate fixing the second support member 62 to the bottom bracket 51, thereby fixing the vibration reduction mechanism 60 to the bottom bracket 51.

[0051] In some embodiments, at least two vibration reduction mechanisms 60 are provided, evenly arranged between the sample chamber 12 and the bottom bracket 51, so as to evenly distribute the force on the electron microscope body 10. Exemplarily, each vibration reduction mechanism 60 is provided with two second support members 62, a buffer pad 63, and an elastic member 64, and a first support member 61. The first support member 61 is provided on the side of the sample chamber 12, and the two second support members 62 are evenly arranged. The buffer pad 63 and the elastic member 64 are respectively provided in a one-to-one correspondence with the second support members 62, so that the four corners of the sample chamber 12 have a buffer vibration reduction structure, thereby being able to isolate vibrations of different frequencies and directions.

[0052] See also Figure 9 In some embodiments, fixing portions 65 are further provided at both ends of the buffer pad 63 , and the fixing portions 65 are used to be inserted and fixed on the first support member 61 and the second support member 62 .

[0053] The above specific examples are used to illustrate the present application, which is only used to help understand the present application and is not intended to limit the present application. For those skilled in the art of the present application, based on the concept of the present application, they can also make some simple deductions, modifications or substitutions.

Claims

1. A scanning electron microscope, characterized in that include: Mounting rack; An electron microscope body, the electron microscope body being arranged in the mounting frame; the electron microscope body comprising a lens barrel and a sample chamber, the lens barrel and the sample chamber being in communication; the lens barrel being provided with a first connection port, the sample chamber being provided with a second connection port; A vibration reduction mechanism, the vibration reduction mechanism being arranged between the mounting frame and the electron microscope body; A vacuum pumping mechanism, the vacuum pumping mechanism is arranged in the mounting frame; the vacuum pumping mechanism is used to vacuum the lens barrel and the sample chamber; the vacuum pumping mechanism is provided with a third connecting port; An adapter, comprising an adapter tube, a first connector, and a second connector, wherein the adapter tube is connected to the third connection port, and the first connector and the second connector are provided on both sides of the adapter tube; as well as A vacuum tube structure, the vacuum tube structure comprising a first flexible tube, a first rigid tube, a second flexible tube, and a second rigid tube, the first flexible tube and the first rigid tube being in communication with each other, one end of the first flexible tube away from the first rigid tube being connected to the first joint to be in communication with the vacuum pumping mechanism via the first joint, and one end of the first rigid tube away from the first flexible tube being connected to the first connecting port to be in communication with the lens barrel via the first connecting port; the second flexible tube and the second rigid tube being in communication, one end of the second flexible tube away from the second rigid tube being connected to the second joint to be in communication with the vacuum pumping mechanism via the second joint, and one end of the second rigid tube away from the second flexible tube being connected to the second connecting port to be in communication with the sample chamber via the second connecting port; The first joint and the second joint are symmetrically arranged on the transition tube along the central axis of the transition tube; the first flexible tube and the second flexible tube are symmetrically arranged along the central axis of the transition tube.

2. The scanning electron microscope according to claim 1, wherein The first rigid tube and the second rigid tube are arranged in parallel.

3. The scanning electron microscope according to claim 2, characterized in that The first rigid tube and the first flexible tube are perpendicular to each other; the second flexible tube and the second rigid tube are perpendicular to each other.

4. The scanning electron microscope according to claim 3, characterized in that The first rigid tube is placed horizontally, and the first flexible tube is placed vertically.

5. The scanning electron microscope according to claim 1, characterized in that The vacuum tube structure further includes a first connecting structure, a second connecting structure, a third connecting structure and a fourth connecting structure, wherein the first connecting structure is used to seal and fix the first joint and the first flexible tube; The second connection structure is used to seal and fix the first flexible tube and the first rigid tube; The third connection structure is used to seal and fix the second joint and the second flexible tube; the fourth connection structure is used to seal and fix the second flexible tube and the second rigid tube.

6. The scanning electron microscope according to claim 5, characterized in that The first connecting structure, the second connecting structure, the third connecting structure and the fourth connecting structure all include a clamp, and the clamp includes an annular body, a fastening bolt and a sealing gasket. The sealing gasket is fitted to the inner wall of the annular body, and the fastening bolt is passed through the open end of the annular body for adjusting the radial size of the annular body.

7. The scanning electron microscope according to claim 1, characterized in that The first flexible tube and the second flexible tube are configured to be made of a corrugated tube.

8. The scanning electron microscope according to claim 1, wherein The mounting frame includes a bottom bracket and a side bracket, and the bottom bracket and the side bracket enclose a storage space. The electron microscope body and the vacuum pumping mechanism are both arranged in the storage space, and the sample chamber is arranged on the bottom bracket, and the lens barrel is arranged on the sample chamber; the vibration damping mechanism is arranged between the sample chamber and the bottom bracket.

9. The scanning electron microscope according to claim 8, characterized in that The vibration reduction mechanism includes a first support member, a second support member, a buffer pad and an elastic member. The first support member is connected to the sample chamber, the second support member is connected to the bottom bracket, the buffer pad is arranged between the first support member and the second support member, and the elastic member is sleeved on the outside of the buffer pad.

10. The scanning electron microscope according to claim 9, characterized in that The second support member is provided with a receiving groove, and at least part of the buffer pad and the elastic member are arranged in the receiving groove; the second support member is provided with a fixing hole, and the fixing hole is used to install a fixing member so that the second support member is fixed to the bottom bracket.

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