Wien filter and electron beam imaging apparatus

Abstract

The invention relates to a Wien filter and electron beam imaging equipment. The Wien filter includes: an electrical deflection member arranged along a circumference and generating an electric field in a first direction; the magnetic deflection component and the electric deflection component are coaxially arranged, the magnetic deflection component is located on the periphery of the electric deflection component, the magnetic deflection component generates a magnetic field in the second direction, and the second direction is orthogonal to the first direction; the periphery of the magnetic deflection part is sleeved with the magnetic shielding cylinder; the first magnetic shielding cover is arranged at the first end of the magnetic shielding cylinder in the axial direction of the magnetic shielding cylinder, and the first magnetic shielding cover is located at one axial end of the magnetic deflection component; the second magnetic shielding cover is arranged at the second end of the magnetic shielding cylinder in the axial direction of the magnetic shielding cylinder, and the second magnetic shielding cover is located at the other end of the magnetic deflection component in the axial direction. The matching degree of electric fields and magnetic fields at the two ends of the Wien filter can be improved, electron beam drift is reduced, and the imaging quality of an electron optical system is improved.

Description

Technical Field

[0001] This application relates to the field of imaging detection technology, and in particular to a Wien filter and an electron beam imaging device. Background Technology

[0002] Semiconductor electron beam-side devices, such as critical dimension scanning electron microscopes (CD-SEMs) and high-end scanning electron microscopes, generally employ in-lens secondary electron detectors (In-lens) to receive secondary electrons (SE) and high-angle backscattered electrons (BSE), aiming for extremely high resolution and signal-to-noise ratio to meet nanometer or even sub-nanometer level measurements. In-lens detectors typically have a central aperture, allowing primary electrons (Photoelectrons, PE) to pass through while preserving space for electron beam alignment. However, this aperture in the In-lens detector results in the loss of some high-resolution SE, leading to reduced resolution and image contrast.

[0003] Currently, related technologies deflect the SE by adding a Wien filter (WF) to the electro-optical system, so that the SE can be fully received by the in-lens without affecting the PE, thus solving the problem of SE loss in the in-lens and enhancing image contrast.

[0004] However, in related technologies, the matching degree between the electric field and the magnetic field at both ends of the Wien filter is poor, which can easily lead to electron beam drift and affect the imaging quality of the electron optical system. Summary of the Invention

[0005] Based on this, embodiments of this application provide a Wien filter and an electron beam imaging device. This improves the matching degree between the electric and magnetic fields at both ends of the Wien filter, reduces electron beam drift, and enhances the imaging quality of the electron optical system.

[0006] On one hand, embodiments of this application provide a Wien filter, including:

[0007] An electric deflection component is arranged circumferentially and generates an electric field in a first direction;

[0008] A magnetic deflection component is coaxially arranged with an electric deflection component and located on the outer periphery of the electric deflection component. The magnetic deflection component generates a magnetic field along a second direction, which is orthogonal to the first direction.

[0009] A magnetic shielding cylinder is fitted around the outer periphery of the magnetic deflection component;

[0010] The first magnetic shielding cover is located at the first end of the magnetic shielding cylinder along the axial direction of the magnetic shielding cylinder. The first magnetic shielding cover is located at one end of the axial direction of the magnetic deflection component.

[0011] The second magnetic shielding cover is located at the second end of the magnetic shielding cylinder along the axial direction of the magnetic shielding cylinder, and at the other end of the magnetic deflection component along the axial direction of the magnetic shielding cylinder.

[0012] In one implementation, the first magnetic shielding cover is provided with a first magnetic shielding screw, which connects the first magnetic shielding cover and the magnetic shielding cylinder.

[0013] The second magnetic shielding cover is equipped with a second magnetic shielding screw, which connects the second magnetic shielding cover to the magnetic shielding cylinder.

[0014] In one implementation, the first magnetic shielding cover has a first central shaft hole, which is coaxial with the magnetic shielding cylinder.

[0015] The second magnetic shielding cover has a second central shaft hole, which is coaxial with the first central shaft hole;

[0016] The radial dimension of either the first central shaft hole or the second central shaft hole is less than or equal to the inner diameter of the magnetic deflection component.

[0017] In one implementation, the end of the first central shaft hole facing the magnetic deflection component has a first chamfer;

[0018] And / or,

[0019] The second central shaft hole has a second chamfer at the end facing the magnetic deflection component.

[0020] In one implementation, the angle of either the first chamfer or the second chamfer is 0° to 60°.

[0021] In one implementation, along the axial direction of the magnetic shielding cylinder, the first magnetic shielding cover has a first dimension, and a second dimension is formed between the end of the first chamfer away from the magnetic deflection component and the side of the first magnetic shielding cover away from the magnetic deflection component; the second dimension is smaller than the first dimension and is greater than one-third of the first dimension;

[0022] And / or,

[0023] In the axial direction of the magnetic shielding cylinder, the second magnetic shielding cover has a third dimension, and the end of the second chamfer away from the magnetic deflection component has a fourth dimension between it and the side of the second magnetic shielding cover away from the magnetic deflection component; the fourth dimension is smaller than the third dimension and is greater than one-third of the third dimension.

[0024] In one implementation, the magnetic deflection component includes:

[0025] The magnetic support is located inside the magnetic shielding cylinder and is used for winding the coil.

[0026] The magnetic core is connected to the side of the magnetic support away from the magnetic shielding cylinder. Along the axial direction of the magnetic shielding cylinder, the end of the magnetic core facing the first magnetic shielding cover has a third chamfer.

[0027] And / or,

[0028] Along the axial direction of the magnetic shielding cylinder, the end of the magnetic core facing the second magnetic shielding cover has a fourth chamfer.

[0029] In one implementation, the angle of either the third or fourth chamfer is 0° to 75°.

[0030] In one implementation, the cut-off dimension of the third chamfer along the axial direction of the magnetic shielding cylinder is the fifth dimension; the dimension by which the magnetic core protrudes from the magnetic support is the sixth dimension; the fifth dimension is less than two-thirds of the sixth dimension;

[0031] And / or,

[0032] Along the axial direction of the magnetic shielding cylinder, the cut-off dimension of the fourth chamfer is the seventh dimension, and the dimension of the magnetic core protruding from the magnetic support is the eighth dimension. The seventh dimension is less than two-thirds of the eighth dimension.

[0033] In one implementation, along the radial direction of the shielding magnetic cylinder, the cross-sectional shape of the magnetic core is a first sector ring, and multiple first sector rings are arranged circumferentially, with the central angle corresponding to the first sector ring being the first central angle; the first central angle is 15°~160°.

[0034] In one implementation, the included angle between the angle bisectors of adjacent first sector rings is the second central angle, which is 15°~165°; wherein, the first central angle is smaller than the second central angle, and the sum of the second central angle and the first central angle is less than 180°.

[0035] In one implementation, the electrical deflection component includes:

[0036] An insulating support member is connected to at least one of a first magnetic shielding cover and a second magnetic shielding cover.

[0037] An electrode plate is connected to an insulating support; along the axial direction of the magnetic shielding cylinder, the end of the electrode plate facing the first magnetic shielding cover has a fifth chamfer; and / or, the end of the electrode plate facing the second magnetic shielding cover has a sixth chamfer.

[0038] In one implementation, the angle of either the fifth or sixth chamfer is 0° to 45°.

[0039] In one implementation, along the axial direction of the magnetic shielding cylinder, the cut-off dimension of either the fifth or sixth chamfer is the ninth dimension; the dimension of the electrode plate is the tenth dimension, and the ninth dimension is less than one-third of the tenth dimension.

[0040] In one implementation, the cross-sectional shape of the electrode plate along the radial direction of the magnetic shielding cylinder is a second sector ring; multiple second sector rings are distributed circumferentially; the central angle corresponding to the second sector ring is the second central angle, which is 15°~75°.

[0041] On the other hand, embodiments of this application provide an electron beam imaging device, including:

[0042] Secondary electron detector;

[0043] The sample stage and the secondary electron detector are arranged along a third direction; and

[0044] The Wien filter provided in the foregoing embodiments of this application is located between the sample stage and the secondary electron detector, and the Wien filter and the electron aperture of the secondary electron detector are coaxial.

[0045] According to the Wien filter and electron beam imaging device provided in the embodiments of this application, an electric field is generated in a first direction by an electric deflection component arranged along the circumference, and a magnetic deflection component is arranged on the outer periphery of the electric deflection component. The magnetic deflection component generates a magnetic field in a second direction, which is orthogonal to the first direction. In this way, when the electron beam enters through the through hole of the secondary electron detector of the electron beam imaging device, the Lorentz force of the magnetic field and the electric field force on the electron beam are opposite in direction, and the Lorentz force and the electric field force can just cancel each other out, which can reduce the interference of the primary electrons by the Wien filter. Furthermore, after the electron beam contacts the sample and generates secondary electrons in opposite directions, the secondary electrons can be deflected under the action of the Lorentz force of the magnetic field and the electric field, thereby increasing the secondary electrons received by the secondary electromagnetic detector, reducing the problem of electron loss by the secondary electron detector, and enhancing image contrast.

[0046] Furthermore, by encasing the magnetic deflection component in a magnetic shielding sleeve, the magnetic shielding sleeve can shield external magnetic fields, reduce the influence of the magnetic field at the objective lens pole piece, and serve as a magnetic field channel for the magnetic deflection component, facilitating adjustment of the magnetic field direction and enhancing the magnetic field strength. Along the axial direction of the magnetic shielding sleeve, a first magnetic shielding cover is positioned at one end of the magnetic shielding sleeve, located at one end of the axial direction of the magnetic deflection component. Thus, along the axial direction of the magnetic deflection component, the outward abrupt change in magnetic field at the end of the magnetic deflection component can enter the first magnetic shielding cover, thereby confining the magnetic field within the Wien filter. In other words, the magnetic field at one end of the magnetic deflection component along the axial direction can be adjusted using the first magnetic shielding cover, reducing the abrupt change in magnetic field at the end of the magnetic deflection component along the axial direction. This improves the matching between the magnetic field and electric field at the end of the magnetic deflection component, reduces the deflection of secondary electrons when entering or leaving the Wien filter along the magnetic deflection component, improves the receiver efficiency of the secondary electron detector, reduces electron beam drift, and enhances the imaging quality of the electron optical system.

[0047] In addition, a second magnetic shielding cover is provided at the second end of the magnetic shielding cylinder along the axial direction of the magnetic shielding cylinder. The second magnetic shielding cover is located at the other end of the axial direction of the magnetic deflection component. In this way, the magnetic field that suddenly changes outward at the end of the magnetic deflection component along the axial direction of the magnetic deflection component can enter the second magnetic shielding cover, thereby confining the magnetic field within the Wien filter through the second magnetic shielding cover. That is to say, the magnetic field at the other end of the magnetic deflection component along the axial direction can be adjusted by the second magnetic shielding cover, which can reduce the sudden change in the magnetic field at the end of the magnetic deflection component along the axial direction. This can improve the matching between the magnetic field and the electric field at the end of the magnetic deflection component, reduce the deflection of secondary electrons when they enter or leave the Wien filter along the magnetic deflection component, improve the receiver rate of the secondary electron detector, reduce electron beam drift, and improve the imaging quality of the electron optical system. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the structure of an electron beam imaging device provided in some embodiments of this application.

[0049] Figure 2 This is another schematic diagram of the structure of the electron beam imaging device provided in some embodiments of this application.

[0050] Figure 3 This is a simplified top view of a Wien filter in an electron beam imaging device provided in some embodiments of this application.

[0051] Figure 4 This is a simulation curve of the electric field and magnetic field matching degree of the Wien filter in the electron beam imaging device provided in some embodiments of this application.

[0052] Figure 5This is a simplified cross-sectional view of a Wien filter in an electron beam imaging device provided in some embodiments of this application.

[0053] Figure 6 This is another simplified cross-sectional view of the Wien filter in the electron beam imaging device provided in some embodiments of this application.

[0054] Figure 7 This is yet another simplified cross-sectional view of the Wien filter in the electron beam imaging device provided in some embodiments of this application.

[0055] Figure 8 This is another simplified top view of the Wien filter in an electron beam imaging device provided in some embodiments of this application.

[0056] Figure 9 This is another simplified top view of the Wien filter in the electron beam imaging device provided in some embodiments of this application.

[0057] Figure 10 This is another simulation curve of the electric field and magnetic field matching degree of the Wien filter in the electron beam imaging device provided in some embodiments of this application.

[0058] Figure 11 These are comparison images of sample test images obtained by the electron beam imaging device provided in some embodiments of this application with test images in related technologies.

[0059] Explanation of reference numerals in the attached figures:

[0060] 10-Wien filter; 20-Secondary electron detector; 30-Sample stage;

[0061] 11-Electrical deflection component; 12-Magnetic deflection component; 13-Magnetic shielding cylinder; 14-First magnetic shielding cover; 15-Second magnetic shielding cover; 21-Electronic through-hole;

[0062] 111-Insulating support; 112-Electrode plate; 121-Magnetic support; 122-Magnetic core; 141-First central shaft hole; 151-Second central shaft hole;

[0063] 1121 - Fifth chamfer; 1122 - Sixth chamfer; 1123 - First electrode plate; 1124 - Second electrode plate; 1125 - Third electrode plate; 1126 - Fourth electrode plate; 1221 - Third chamfer; 1222 - Fourth chamfer; 1223 - First magnetic core; 1224 - Second magnetic core; 1225 - Third magnetic core; 1226 - Fourth magnetic core; 1411 - First chamfer; 1511 - Second chamfer. Detailed Implementation

[0064] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0065] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0066] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0067] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0068] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0069] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0070] Figure 1 This is a schematic diagram of the structure of an electron beam imaging device provided in some embodiments of this application.

[0071] In some examples, refer to Figure 1 As shown, this application embodiment provides an electron beam imaging device, which may include a secondary electron detector 20. It is understood that the secondary electron detector 20 may include an In-lens detector. The secondary electron detector 20 may be the same as, similar to, or analogous to detectors in related technologies; for details, please refer to the detailed descriptions in related technologies, which will not be repeated here.

[0072] In some examples, refer to Figure 1 As shown, the electron beam imaging device may include a sample stage 30. The specific structure of the sample stage 30 may be the same as, similar to, or analogous to the sample stage 30 in related technologies, and can be referred to the detailed description in related technologies. This embodiment will not repeat the details here. It is understood that the sample stage 30 can be used to hold a sample.

[0073] In some examples, refer to Figure 1 As shown, the sample stage 30 can be arranged side by side with the secondary electron detector 20.

[0074] In some examples, refer to Figure 1As shown, the secondary electron detector 20 may be provided with an electron through-hole 21. The electron through-hole 21 can penetrate through both surfaces of the detector. Primary electrons can pass through the electron through-hole 21 and irradiate the sample on the sample stage 30.

[0075] In some examples, refer to Figure 1 As shown, a primary electron beam irradiates the sample on the sample stage 30 through the electron aperture 21. The secondary electrons generated after exciting the sample are directed in the opposite direction (as indicated by arrows b and b1) and irradiate the secondary electron detector 20, where they are received and a high-resolution image is formed. In other words, in some examples of this application's embodiments, secondary electrons are distributed in the region between arrows b and b1. Some of these electrons are lost through the electron aperture 21, resulting in reduced image resolution and contrast.

[0076] Figure 2 This is another schematic diagram of the structure of the electron beam imaging device provided in some embodiments of this application.

[0077] In some examples, refer to Figure 2 As shown, the electron beam imaging device provided in this application embodiment may include a Wien filter 10. The Wien filter 10 may be located between the sample stage 30 and the secondary electron detector 20.

[0078] In some examples, refer to Figure 2 As shown, the Wien filter 10 can be coaxially arranged with the electronic through-hole 21.

[0079] In other words, after primary electrons pass through electron aperture 21, they can pass through Wien filter 10 and then irradiate the sample on sample stage 30; secondary electrons generated after sample excitation can pass through Wien filter 10 and then irradiate the secondary electron detector 20.

[0080] Figure 3 This is a simplified top view of a Wien filter in an electron beam imaging device provided in some embodiments of this application.

[0081] In some examples, refer to Figure 3 As shown, the Wien filter 10 may include an electrical deflection component 11. The electrical deflection component 11 may be arranged circumferentially and along a first direction (e.g., Figure 3 An electric field is generated in the direction indicated by the middle arrow E.

[0082] In some examples, refer to Figure 3As shown, the electric deflection component 11 may include at least one set of electrode pairs, which may be arranged coaxially and circumferentially. That is, the electrodes of the electric deflection component 11 may be configured as arc-shaped, and the arc-shaped electrode pairs may be arranged around the same axis and on the same circumference. In this way, the uniformity of the electric field generated along the first direction can be improved.

[0083] In some examples, refer to Figure 3 As shown, the Wien filter 10 may include a magnetic deflection component 12. The magnetic deflection component 12 may be coaxially arranged with the electrical deflection component 11. For example, see reference... Figure 3 As shown, the electrode pair of the electrical deflection component 11 can rotate around Figure 3 The magnetic deflection component 12 is arranged circumferentially around point O as the central axis. Figure 3 Point O is used as the axis for circumferential arrangement.

[0084] In some examples, refer to Figure 3 As shown, the magnetic deflection component 12 can be located on the outer periphery of the electric deflection component 11. In this way, it can be ensured that there is no interference between the electrode pairs of the electric deflection component 11, and the magnetic deflection component 12 can be prevented from interfering with the electric field generated by the electric deflection component 11, thus ensuring the stability and uniformity of the electric field provided by the electric deflection component 11.

[0085] In some examples, the magnetic deflection component 12 may include at least one set of magnetic pole pairs. The magnetic poles may be arc-shaped. The arc-shaped magnetic poles may be coaxially arranged. For example, the magnetic pole pairs may be arranged around... Figure 3 Point O is used as the central axis for the circular arrangement. It can be understood that magnetic pole pairs can be arranged on the same circle.

[0086] In some examples, the magnetic deflection component 12 can be along a second direction (e.g., Figure 3 The direction indicated by arrow B generates a magnetic field. The second direction can intersect the first direction. For example, the second direction can be perpendicular to the first direction.

[0087] In some examples, refer to Figure 3 As shown, when the primary electron beam enters through the electron aperture 21, the force exerted on the primary electron in the electric field generated by the electric deflection component 11 is equal in magnitude to the Lorentz force exerted on the primary electron in the magnetic field generated by the magnetic deflection component 12 (this equality can be ensured by adjusting the electric and magnetic field strengths). Furthermore, the force exerted on the primary electron in the electric field generated by the electric deflection component 11 is opposite in direction to the Lorentz force exerted on the primary electron in the magnetic field generated by the magnetic deflection component 12 (this opposite direction can be ensured by adjusting the directions of the electric and magnetic fields). Thus, the resultant force exerted on the primary electron by the electric deflection component 11 and the magnetic deflection component 12 is zero, and it will not affect the motion of the primary electron beam.

[0088] In some examples, refer to Figure 2 As shown, after the primary electron beam irradiates the sample on the sample stage 30, secondary electrons are generated. The direction of motion of the secondary electron beam is opposite to that of the primary electron beam. At this time, the electric field force and Lorentz force exert a deflection force on the secondary electron beam, causing it to deflect in one direction. This allows the secondary electron beam to avoid the electron aperture 21 on the secondary electron detector 20, thereby improving the receiving rate of the secondary electron detector 20. This can improve image contrast and imaging quality.

[0089] In some examples, refer to Figure 2 As shown, during the process of the electron beam entering or leaving the Wien filter 10, that is, along the arrangement direction of the secondary electron detector 20 and the sample stage 30, there may be some magnetic fields overflowing from the magnetic deflection components 12 at both ends of the Wien filter 10. This part of the magnetic field may deflect the moving electron beam, causing the electron beam to drift and affecting the imaging quality.

[0090] Figure 4 This is a simulation curve of the electric field and magnetic field matching degree of the Wien filter in the electron beam imaging device provided in some embodiments of this application.

[0091] In some examples, refer to Figure 4 As shown, Figure 4 The solid line c represents the curve showing the variation of the electric field generated by the electric deflection component 11 along the axial direction of the Wien filter 10. Figure 4 The dashed line d represents the curve showing the variation of the magnetic field generated by the magnetic deflection component 12 along the axial direction of the Wien filter 10. From... Figure 4 It can be seen that at both ends of the axial direction of the Wien filter 10, the magnetic field generated by the magnetic deflection component 12 and the electric field generated by the electric deflection component 11 are poorly matched. In other words, at both ends of the axial direction of the Wien filter 10, the primary electron beam is subjected to an imbalance of electric and magnetic forces, and the primary electron beam has a certain degree of drift, resulting in poor imaging quality.

[0092] Figure 5 This is a simplified cross-sectional view of a Wien filter in an electron beam imaging device provided in some embodiments of this application. Figure 6 This is another simplified cross-sectional view of the Wien filter in the electron beam imaging device provided in some embodiments of this application. Figure 7 This is yet another simplified cross-sectional view of the Wien filter in the electron beam imaging device provided in some embodiments of this application.

[0093] In some examples, refer to Figures 5-7 As shown, the Wien filter 10 may include a magnetic shielding cylinder 13. The magnetic shielding cylinder 13 may be fitted around the outer periphery of the magnetic deflection component 12.

[0094] In some examples, the magnetic shielding cylinder 13 can be a cylindrical structure. The magnetic shielding cylinder 13 can be coaxial with the magnetic deflection component 12. That is, the axis of the magnetic shielding cylinder 13 can coincide with the axis of the magnetic deflection component 12. In this way, it can be ensured that the magnetic shielding cylinder 13 can uniformly shield the magnetic field outward from the magnetic deflection component 12, thereby improving the uniformity of the magnetic field generated by the magnetic deflection component 12.

[0095] In some examples, the inner diameter of the magnetic shielding cylinder 13 can be greater than or equal to the outer diameter of the magnetic deflection component 12. This facilitates the installation of the magnetic deflection component 12 into the magnetic shielding cylinder 13.

[0096] In some examples, the outer side of the magnetic deflection component 12 can contact the inner wall of the magnetic shielding cylinder 13 and be fixedly connected to the inner wall of the magnetic shielding cylinder 13. This facilitates the fixing of the magnetic deflection component 12.

[0097] In some examples, there may be a certain gap between the outer side of the magnetic deflection component 12 and the inner wall of the magnetic shielding cylinder 13 (see reference). Figure 7 (As shown). This facilitates the installation of the magnetic deflection component 12 into the magnetic shielding cylinder 13.

[0098] In some examples, refer to Figures 5-7 As shown, the axial dimension of the magnetic shielding cylinder 13 can be larger than the axial dimension of the magnetic deflection component 12. This facilitates the magnetic shielding cylinder 13 in shielding the magnetic field outward from the magnetic deflection component 12.

[0099] In some examples, the magnetic shielding cylinder 13 can be made of a highly permeable material. For example, the permeability of the magnetic shielding cylinder 13 can be greater than 80,000. It is understood that in some examples of the embodiments of this application, the permeability of the magnetic shielding cylinder 13 is only used as a specific example for illustration and is not intended to limit the permeability of the magnetic shielding cylinder 13.

[0100] In some examples, the magnetic shielding cylinder 13 may be made of at least one of a high-permeability metal, a high-permeability ceramic, or a high-permeability polyether ether ketone (PEEK). The high-permeability PEEK may be a polymer composite material obtained by modifying PEEK with functional fillers (e.g., ferrite, carbonyl iron powder, permalloy powder, or other magnetic ceramic particles).

[0101] In some examples, the outer diameter of the magnetic shielding cylinder 13 can be 56mm to 64mm.

[0102] In some examples, the outer diameter of the magnetic shielding cylinder 13 can be 58mm to 64mm.

[0103] In some examples, the outer diameter of the magnetic shielding cylinder 13 can be 56mm to 62mm.

[0104] In some examples, the outer diameter of the magnetic shielding cylinder 13 can be 60 mm.

[0105] In some examples, the inner diameter of the magnetic shielding cylinder 13 can be 50mm to 54mm.

[0106] In some examples, the inner diameter of the magnetic shielding cylinder 13 can be 51mm to 54mm.

[0107] In some examples, the inner diameter of the magnetic shielding cylinder 13 can be 50mm to 53mm.

[0108] In some examples, the inner diameter of the magnetic shielding cylinder 13 can be 52 mm.

[0109] It should be noted that the numerical values ​​and ranges involved in the embodiments of this application are approximate values. Due to the influence of the manufacturing process, there may be a certain range of errors, which can be considered negligible by those skilled in the art.

[0110] In some examples of embodiments of this application, a magnetic shielding cylinder 13 is fitted around the outer periphery of the magnetic deflection component 12. The magnetic shielding cylinder 13 can shield external magnetic fields. For example, the magnetic shielding cylinder 13 can shield the magnetic field at the objective lens pole piece, which can reduce or eliminate the interference of external magnetic fields on the electron beam and help improve imaging quality. In addition, the magnetic shielding cylinder 13 can act as a channel for the magnetic field, allowing the magnetic field generated outward by the magnetic deflection component 12 to enter the magnetic shielding cylinder 13, which is beneficial for adjusting the direction of the magnetic field generated by the magnetic deflection component 12 and enhancing its strength. Furthermore, the magnetic shielding cylinder 13 can shield the magnetic field generated by the magnetic deflection component 12, which can constrain the magnetic field range of the magnetic deflection component 12 and prevent the magnetic field generated by the magnetic deflection component 12 from spreading outward and interfering with the normal operation of other magnetic components (such as objective lens pole pieces, condenser lenses, etc.) in the electron beam imaging device.

[0111] In some examples, refer to Figures 5-7 As shown, the Wien filter 10 may include a first magnetic shielding cover 14. Along the axial direction of the magnetic shielding cylinder 13 (e.g., Figures 5 to 7 (As shown in i1), the first magnetic shielding cover 14 can be disposed at the first end of the magnetic shielding cylinder 13.

[0112] In some examples, the first end of the magnetic shielding cylinder 13 may refer to the end of the magnetic shielding cylinder 13 facing the secondary electronic detector 20.

[0113] In some examples, the first magnetic shielding cover 14 may be located at one end of the magnetic deflection component 12 along its axial direction. The first magnetic shielding cover 14 may be located at the end of the magnetic deflection component 12 that faces the secondary electron detector 20 along its axial direction.

[0114] In some examples, the first magnetic shielding cover 14 can be made of a high magnetic permeability material. The material of the first magnetic shielding cover 14 can be the same as, similar to or similar to that of the magnetic shielding cylinder 13. For details, please refer to the detailed description of the foregoing embodiments of this application, which will not be repeated here.

[0115] In some examples, the first magnetic shielding cover 14 can be fixedly connected to the magnetic shielding cylinder 13 by connecting components such as screws, bolts, or threaded rods. The screws, bolts, or threaded rods can be made of highly permeable magnetic materials. The material of the screws, bolts, or threaded rods can be the same as, similar to, or similar to that of the magnetic shielding cylinder 13, as detailed in the foregoing embodiments of this application.

[0116] In some examples of embodiments of this application, a first magnetic shielding cover 14 is provided at the first end of the magnetic shielding cylinder 13 along the axial direction. The first magnetic shielding cover 14 is located at one end of the axial direction of the magnetic deflection component 12. In this way, the magnetic field generated at the axial end of the magnetic deflection component 12 will preferentially enter the first magnetic shielding cover 14 with higher magnetic permeability, which can reduce the magnetic field that diffuses outward along the axial direction at the axial end of the magnetic deflection component 12. This allows the magnetic field to be confined between the magnetic deflection component 12 and the first magnetic shielding cover 14, thereby reducing the outward overflow of the magnetic field along the axial direction. In other words, by providing the first magnetic shielding cover 14, the axial distribution range of the magnetic field generated by the magnetic deflection component 12 can be effectively constrained, reducing the diffusion of the magnetic field along the axial direction. This can improve the matching degree between the magnetic field and electric field at the axial end position of the Wien filter 10, reduce the magnetic field abrupt change at the axial end of the Wien filter 10, reduce the primary electron beam drift, and improve the imaging quality.

[0117] In some examples, refer to Figures 5-7 As shown, the Wien filter 10 may include a second magnetic shielding cover 15. Along the axial direction of the magnetic shielding cylinder 13, the second magnetic shielding cover 15 may be disposed at the second end of the magnetic shielding cylinder 13.

[0118] In some examples, the second end may refer to the end of the magnetic shielding cylinder 13 opposite to the first end. Alternatively, the second end may refer to the end of the magnetic shielding cylinder 13 facing the sample stage 30.

[0119] In some examples, the second magnetic shielding cover 15 may be located at the other end of the magnetic deflection component 12 along its axial direction. Along the axial direction of the magnetic deflection component 12, the second magnetic shielding cover 15 may be disposed opposite to the first magnetic shielding cover 14.

[0120] In some examples, the second magnetic shielding cover 15 may be configured in the same, similar or similar way to the first magnetic shielding cover 14. For details, please refer to the detailed description of the first magnetic shielding component in the foregoing embodiments of this application. This application will not repeat the details in the embodiments.

[0121] In some examples of embodiments of this application, a second magnetic shielding cover 15 is provided at the second end of the magnetic shielding cylinder 13 along the axial direction. The second magnetic shielding cover 15 is located at the other end of the axial direction of the magnetic deflection component 12. In this way, the magnetic field generated at the axial end of the magnetic deflection component 12 will preferentially enter the second magnetic shielding cover 15 with higher magnetic permeability. This can reduce the magnetic field that diffuses outward along the axial direction at the axial end of the magnetic deflection component 12, so that the magnetic field can be confined between the magnetic deflection component 12 and the second magnetic shielding cover 15, thereby reducing the outward overflow of the magnetic field along the axial direction. In other words, by providing the second magnetic shielding cover 15, the axial distribution range of the magnetic field generated by the magnetic deflection component 12 can be effectively constrained, the diffusion of the magnetic field along the axial direction can be reduced, the matching degree between the magnetic field and electric field at the axial end position of the Wien filter 10 can be improved, the magnetic field abrupt change at the axial end position of the Wien filter 10 can be reduced, the primary electron beam drift can be reduced, and the imaging quality can be improved.

[0122] According to the Wien filter 10 provided in the embodiments of this application, an electric field is generated in a first direction by an electric deflection component 11 arranged along the circumference, and a magnetic deflection component 12 is provided on the outer periphery of the electric deflection component 11. The magnetic deflection component 12 generates a magnetic field in a second direction, which is orthogonal to the first direction. In this way, when the electron beam enters through the through hole of the secondary electron detector 20 of the electron beam imaging device, the Lorentz force of the magnetic field and the electric field force of the electron beam are opposite in direction, and the Lorentz force and the electric field force can just cancel each other out, which can reduce the interference of the primary electrons by the Wien filter 10. Furthermore, after the electron beam contacts the sample and generates secondary electrons in the opposite direction, the secondary electrons can be deflected under the action of the Lorentz force of the magnetic field and the electric field, thereby increasing the secondary electrons received by the secondary electromagnetic detector, reducing the problem of electron loss by the secondary electron detector 20, and enhancing image contrast.

[0123] Furthermore, by encasing the magnetic deflection component 12 with a magnetic shielding cylinder 13, the magnetic shielding cylinder 13 can shield external magnetic fields, reduce the influence of the magnetic field at the objective lens pole piece, and the magnetic shielding cylinder 13 can also serve as a magnetic field channel for the magnetic deflection component 12, facilitating the adjustment of the magnetic field direction and enhancement of the magnetic field strength. Along the axial direction of the magnetic shielding cylinder 13, a first magnetic shielding cover 14 is provided at one end of the magnetic shielding cylinder 13, located at one end of the axial direction of the magnetic deflection component 12. Thus, along the axial direction of the magnetic deflection component 12, the outwardly abrupt magnetic field at the end of the magnetic deflection component 12 can enter the first magnetic shielding cover 14. The magnetic field is confined within the Wien filter 10 by the first magnetic shielding cover 14. In other words, the magnetic field at one end of the magnetic deflection component 12 along the axial direction can be adjusted by the first magnetic shielding cover 14, which can reduce the sudden change in the magnetic field at the end of the magnetic deflection component 12 along the axial direction. This can improve the matching between the magnetic field and the electric field at the end of the magnetic deflection component 12, reduce the deflection of secondary electrons when they enter or leave the Wien filter 10 along the magnetic deflection component 12, improve the receiver efficiency of the secondary electron detector 20, reduce electron beam drift, and improve the imaging quality of the electron optical system.

[0124] In addition, along the axial direction of the magnetic shielding cylinder 13, a second magnetic shielding cover 15 is provided at the second end of the magnetic shielding cylinder 13, and the second magnetic shielding cover 15 is located at the other end of the axial direction of the magnetic deflection component 12. In this way, along the axial direction of the magnetic deflection component 12, the magnetic field that suddenly changes outward at the end of the magnetic deflection component 12 can enter the second magnetic shielding cover 15, thereby confining the magnetic field within the Wien filter 10 through the second magnetic shielding cover 15. That is to say, the magnetic field at the other end of the magnetic deflection component 12 along the axial direction can be adjusted by the second magnetic shielding cover 15, which can reduce the sudden change in the magnetic field at the end of the magnetic deflection component 12 along the axial direction, thereby improving the matching between the magnetic field and the electric field at the end of the magnetic deflection component 12, reducing the deflection of secondary electrons when entering or leaving the Wien filter 10 along the magnetic deflection component 12, improving the receiver efficiency of the secondary electron detector 20, reducing electron beam drift, and improving the imaging quality of the electron optical system.

[0125] In some examples, the first magnetic shielding cover 14 may be provided with a first magnetic shielding screw. The first magnetic shielding screw can connect the first magnetic shielding cover 14 and the magnetic shielding cylinder 13.

[0126] In some examples, the material of the first magnetic shielding screw may be the same as, similar to, or similar to that of the magnetic shielding cylinder 13. For details, please refer to the detailed description of the foregoing embodiments of this application; further elaboration will not be repeated in the embodiments of this application.

[0127] In some examples of embodiments of this application, the first magnetic shielding cover 14 and the magnetic shielding cylinder 13 are connected by a first magnetic shielding screw. Thus, the material of the first magnetic shielding screw is consistent with that of the magnetic shielding cylinder 13 and the first magnetic shielding cover 14, forming a continuous magnetic resistance barrier between the first magnetic shielding cover 14 and the magnetic shielding cylinder 13. This strengthens the constraint on abrupt changes in the magnetic field at the axial end of the magnetic deflection component 12, reducing magnetic field leakage to the outside of the Wien filter 10. Furthermore, the screw connection ensures a tight fit between the first magnetic shielding cover 14 and the magnetic shielding cylinder 13, eliminating potential magnetic field dissipation channels caused by assembly gaps, improving the uniformity of the magnetic field distribution at the end of the magnetic deflection component 12, enhancing the spatial matching accuracy of the magnetic and electric fields, and reducing the additional deflection caused by abrupt changes in the magnetic field when secondary electrons enter and exit the Wien filter 10 axially. This improves the reception rate of the secondary electron detector 20 for target electrons, effectively suppresses electron beam drift during transmission, and ensures the clarity and stability of the electron optical system imaging.

[0128] In some examples, the second shielding cover may be equipped with a second magnetic shielding screw. The second magnetic shielding screw can connect the second magnetic shielding cover 15 to the magnetic shielding cylinder 13.

[0129] It is understood that in some examples of the embodiments of this application, the arrangement of the second magnetic shielding screw may be the same as, similar to, or analogous to that of the first magnetic shielding screw. For details, please refer to the detailed description of the first magnetic shielding screw in the foregoing embodiments of this application; further details will not be repeated here. Additionally, the second magnetic shielding screw can achieve the same or similar technical effects as the first magnetic shielding screw; further details will not be repeated here.

[0130] In some examples, refer to Figures 5-7 As shown, the first magnetic shielding cover 14 may have a first central shaft hole 141, and the first central shaft hole 141 may be coaxial with the magnetic shielding cylinder 13.

[0131] In some examples, the cross-sectional shape of the first magnetic shielding cover 14 may be annular. The axis of the annular first magnetic shielding cover 14 may coincide with the axis of the magnetic shielding cylinder 13.

[0132] In some examples, the radial dimension of the first central shaft hole 141 can be less than or equal to the inner diameter of the magnetic deflection component 12. That is, referring to... Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the first magnetic shielding cover 14 can cover the end of the magnetic deflection component 12.

[0133] In some examples of embodiments of this application, a first central shaft hole 141 is provided in the first magnetic shielding cover 14. The first central shaft hole 141 is coaxial with the magnetic shielding cylinder 13, and the radial dimension of the first central shaft hole 141 is set to be less than or equal to the inner diameter of the magnetic deflection component 12. In this way, the design of the first central shaft hole 141 being coaxial with the magnetic shielding cylinder 13 can ensure that the electron beam's movement path is always in the central region of the magnetic shielding structure when passing through the magnetic deflection component 12, thereby improving the deflection accuracy and stability of the electron beam. The radial dimension of the first central shaft hole 141 is less than or equal to the inner diameter of the magnetic deflection component 12, so that the first magnetic shielding cover 14 can cover the end of the magnetic deflection component 12 while reserving a precise passage for the electron beam. This effectively blocks external stray magnetic fields from intruding into the interior of the magnetic deflection component 12 from the end, without hindering the normal transmission of the electron beam, thus enhancing the magnetic shielding effect. In addition, the structure of the annular first magnetic shielding cover 14 and the magnetic shielding cylinder 13 coinciding with the axis can make the magnetic field distribution between the magnetic shielding cover and the magnetic shielding cylinder 13 more uniform, reduce the abrupt change of the magnetic field at the connection point, reduce the impact of the magnetic field edge effect on the electron beam deflection, and improve the imaging quality of the entire electron beam imaging device.

[0134] In some examples, refer to Figures 5-7 As shown, the second magnetic shielding cover 15 may have a second central shaft hole 151, which may be coaxial with the first central shaft hole 141. That is, the second central shaft hole 151 may be coaxial with the magnetic shielding cylinder 13.

[0135] In some examples, the radial dimension of the second central shaft hole 151 may be less than or equal to the inner diameter of the magnetic deflection component 12.

[0136] It is understood that in some examples of the embodiments of this application, the arrangement of the second central shaft hole 151 may be the same as, similar to, or similar to the arrangement of the first central shaft hole 141. For details, please refer to the detailed description of the foregoing embodiments of this application; further details will not be repeated here. Additionally, the arrangement of the second central shaft hole 151 can achieve the same, similar to, or similar technical effects as the first central shaft hole 141. For details, please refer to the detailed description of the first central shaft hole 141 in the foregoing embodiments of this application; further details will not be repeated here.

[0137] In some examples, the outer diameter of the first shielding cover may be the same as or similar to the outer diameter of the magnetic shielding cylinder 13.

[0138] In some examples, the inner diameter of the first magnetic shielding cover 14 can be 18mm to 22mm.

[0139] In some examples, the inner diameter of the first magnetic shielding cover 14 can be 19mm to 22mm.

[0140] In some examples, the inner diameter of the first magnetic shielding cover 14 can be 18mm to 21mm.

[0141] In some examples, the inner diameter of the first magnetic shielding cover 14 can be 20 mm.

[0142] In some examples, the inner diameter of the second magnetic shielding cover 15 may be the same as, similar to, or similar to the inner diameter of the first magnetic shielding cover 14. For details, please refer to the detailed description of the first magnetic shielding cover 14 in the foregoing embodiments of this application; further details will not be repeated in the embodiments of this application.

[0143] In some examples, refer to Figures 5-7 As shown, the end of the first central shaft hole 141 facing the magnetic deflection component 12 may be provided with a first chamfer 1411.

[0144] In some examples, the angle between the inner wall of the first shielding cover and the surface facing the magnetic deflection component 12 can be cut to form a first chamfer 1411.

[0145] In some examples, refer to Figures 5-7 As shown, the first chamfer 1411 can refer to the acute angle between the bevel formed by cutting the angle between the inner wall of the first shielding cover and the surface facing the magnetic deflection component 12, and the inner wall of the first shielding cover. For example... Figures 5-7 Angle α in the equation.

[0146] In some examples, after the first chamfer 1411 is provided in the first central shaft hole 141, the radial dimension of the end of the first central shaft hole 141 facing the magnetic deflection component 12 can be a first radial dimension.

[0147] In some examples, the first radial dimension can be 20mm to 24mm.

[0148] In some examples, the first radial dimension can be 21mm to 24mm.

[0149] In some examples, the first radial dimension can be 20mm to 23mm.

[0150] In some examples, the first radial dimension can be 22 mm.

[0151] In some examples of embodiments of this application, a first chamfer 1411 is provided at one end of the first central shaft hole 141 facing the magnetic deflection component 12. The first chamfer 1411 can reduce the local concentration of the magnetic field at the angle between the inner sidewall of the first magnetic shielding cover 14 and the surface facing the magnetic deflection component 12, making the magnetic field transition at the axial end of the magnetic deflection component 12 smoother, reducing the abrupt change region of the magnetic field, improving the matching between the magnetic field and the electric field, and reducing the drift of the primary and secondary electron beams. This can improve imaging quality and contrast.

[0152] Furthermore, a first chamfer 1411 is provided at the end of the first central shaft hole 141 facing the magnetic deflection component 12. In this way, the first chamfer 1411 can make the hole wall of the first central shaft hole 141 form a smooth transition with the emission direction of the electron beam, which can reduce the probability of contact between electrons and the hole wall, reduce the number of scattered electrons, improve the focusing accuracy of the electron beam, and thus improve the image clarity and contrast.

[0153] In some examples, the end of the second central shaft hole 151 facing the magnetic deflection component 12 may be provided with a second chamfer 1511.

[0154] In some examples, the second chamfer 1511 may be formed in the same, similar or similar way to the first chamfer 1411. For details, please refer to the detailed description of the first chamfer 1411 in the foregoing embodiments of this application. This application will not repeat the details in the embodiments.

[0155] In some examples, the angle of either the first chamfer 1411 or the second chamfer 1511 can be 0° to 60°.

[0156] In some examples, the angle of the first chamfer 1411 can be 0° to 60°.

[0157] In some examples, the angle of the first chamfer 1411 can be 20° to 60°.

[0158] In some examples, the angle of the first chamfer 1411 can be 0° to 40°.

[0159] In some examples, the angle of the first chamfer 1411 can be 30°.

[0160] In some examples, the angle of the second chamfer 1511 can be 0° to 60°.

[0161] In some examples, the angle of the second chamfer 1511 can be 20° to 60°.

[0162] In some examples, the angle of the second chamfer 1511 can be 50°.

[0163] In some examples of embodiments of this application, by setting the angle of either the first chamfer 1411 or the second chamfer 1511 to 0°~60°, the transmission path of the electron beam within the first central axis aperture 141 and the second central axis aperture 151 can be effectively optimized, reducing the probability of the electron beam colliding with the aperture wall, reducing electron scattering loss, and thus improving the transmission efficiency and stability of the electron beam. Furthermore, setting the angle of the first chamfer 1411 and the second chamfer 1511 to 0°~60° can guide the electron beam to enter the magnetic deflection component 12 uniformly, avoiding electron beam deflection caused by uneven distribution of local electric or magnetic fields. This helps the magnetic deflection component 12 to more accurately control the deflection direction and angle of the electron beam, improving the imaging quality of the electron beam imaging device.

[0164] In some examples, refer to Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the first magnetic shielding cover 14 may have a first dimension L1. That is, the thickness of the first magnetic shielding cover 14 may be the first dimension L1.

[0165] In some examples, the end of the first chamfer 1411 away from the magnetic deflection component 12 may have a second dimension L2 between it and the side of the first magnetic shielding cover 14 away from the magnetic deflection component 12.

[0166] In some examples, the second dimension L2 may be smaller than the first dimension L1.

[0167] In some examples, the second dimension L2 can be one-third larger than the first dimension L1.

[0168] In some examples of embodiments of this application, the first magnetic shielding cover 14 has a first dimension L1 along the axial direction of the magnetic shielding cylinder 13. The distance between the end of the first chamfer 1411 away from the magnetic deflection component 12 and the side of the first magnetic shielding cover 14 away from the magnetic deflection component 12 is set as a second dimension L2. The second dimension is set to be smaller than the first dimension L1, and the second dimension L2 is greater than one-third of the first dimension L1. This allows the first chamfer 1411 to retain sufficient guiding length in the axial direction of the magnetic shielding cover, ensuring that the magnetic field at the axial end of the magnetic deflection component 12 can enter the first magnetic shielding cover 14 from the first chamfer 1411. This reduces the abrupt change in the magnetic field at the axial end of the magnetic deflection component 12, resulting in a tighter magnetic field coupling between the magnetic deflection component 12 and the first magnetic shielding cover 14. This also makes the magnetic field distribution in the magnetic deflection component 12 more gradual, reducing electron beam drift and improving imaging clarity and contrast.

[0169] In some examples, the axial dimension of the magnetic shielding cylinder 13 can be 38mm to 42mm.

[0170] In some examples, the axial dimension of the magnetic shielding cylinder 13 can be 39mm to 42mm.

[0171] In some examples, the axial dimension of the magnetic shielding cylinder 13 can be 38mm to 41mm.

[0172] In some examples, the axial dimension of the magnetic shielding cylinder 13 can be 40 mm.

[0173] In some examples, the first dimension L1 can be 2.8mm to 3.2mm.

[0174] In some examples, the first dimension L1 can be 2.9mm to 3.2mm.

[0175] In some examples, the first dimension L1 can be 2.8mm to 3.1mm.

[0176] In some examples, the first dimension L1 can be 3mm.

[0177] In some examples, the second dimension L2 can be 1mm to 2mm. For example, the second dimension can be 1.5mm.

[0178] In some examples, refer to Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the second magnetic shielding cover 15 may have a third dimension L3.

[0179] In some examples, along the axial direction of the magnetic shielding cylinder 13, the end of the second chamfer 1511 away from the magnetic deflection component 12 and the side of the second magnetic shielding cover 15 away from the magnetic deflection component 12 may have a fourth dimension L4.

[0180] In some examples, the fourth dimension L4 can be smaller than the third dimension L3. The fourth dimension L4 can be greater than one-third of the third dimension L3.

[0181] In some examples, the fourth dimension L4 can be 1mm to 3mm. For example, the fourth dimension L4 can be 2mm.

[0182] It is understood that in some examples of the embodiments of this application, the relationship between the fourth dimension L4 and the third dimension L3 may be the same as, similar to or similar to the relationship between the second dimension L2 and the first dimension L1 in the foregoing embodiments of this application. For details, please refer to the detailed description of the foregoing embodiments of this application. The embodiments of this application will not repeat the details here.

[0183] In some examples, the magnetic deflection component 12 may include a magnetic support 121. The magnetic support 121 may be located inside the magnetic shielding cylinder 13. The magnetic support 121 may be used to wind a coil.

[0184] In some examples, the magnetic support 121 can be fixedly connected to the inner wall of the magnetic shielding cylinder 13. For example, it can be fixedly connected to the inner wall of the magnetic shielding cylinder 13 by connecting components such as screws, bolts, or threaded rods.

[0185] In some examples, the magnetic support 121 may have a certain gap with the inner wall of the magnetic shielding cylinder 13 (e.g., see reference). Figure 7 (As shown).

[0186] In some examples, the magnetic support 121 can be a cubic structure. The magnetic support 121 can be arranged symmetrically with respect to one of the diameters of the magnetic shielding cylinder 13.

[0187] In some examples, the magnetic support 121 can be made of a highly permeable magnetic material. For example, the material of the magnetic support 121 can be the same as, similar to, or similar to the material of the magnetic shielding cylinder 13 in the foregoing embodiments of this application.

[0188] In some examples, the magnetic deflection component 12 may include a magnetic core 122. The magnetic core 122 may be attached to the side of the magnetic support 121 away from the magnetic shielding cylinder 13.

[0189] In some examples, the magnetic core 122 and the magnetic support 121 can be a single unit.

[0190] In some examples, the magnetic core 122 can generate a magnetic field under the excitation of a coil wound on the magnetic support 121.

[0191] In some examples, refer to Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the end of the magnetic core 122 facing the first magnetic shielding cover 14 may be provided with a third chamfer 1221.

[0192] It is understood that the setting method of the third chamfer 1221 can be the same as, similar to or similar to the setting method of the first chamfer 1411 and the second chamfer 1511 in the foregoing embodiments of this application. For details, please refer to the detailed description of the first chamfer 1411 and the second chamfer 1511 in the foregoing embodiments of this application. This application will not repeat the details.

[0193] In some examples of embodiments of this application, a magnetic support member 121 is provided inside the magnetic shielding cylinder 13, and a magnetic core 122 is provided on the side of the support member away from the magnetic shielding cylinder 13; along the axial direction of the magnetic shielding cylinder 13, a third chamfer 1221 is provided at the end of the magnetic core 122 facing the first magnetic shielding cover 14. In this way, the third chamfer 1221 guides the magnetic field at the axial end of the magnetic deflection component 12, while the first chamfer 1411 of the first shielding cover guides the magnetic field at the axial end of the magnetic deflection component 12 into the first magnetic shielding cover 14; that is, the magnetic field at the axial end of the magnetic deflection component 12 flows from the third chamfer 1221 to the first chamfer 1411, forming a closed magnetic field loop in the first shielding end cover and the magnetic shielding cylinder 13, reducing the abrupt change in the transmission of the magnetic field from the magnetic core 122 to the first shielding end cover, ensuring the uniformity of the axial magnetic field distribution of the magnetic deflection component 12, and reducing the abrupt change in the magnetic field at the end of the Wien filter 10. This design ensures a smooth transition of the magnetic field along the axis of the magnetic shielding cylinder 13, thereby improving the deflection accuracy and stability of the electron beam as it passes through the Wien filter 10. This enhances image sharpness and contrast, thus improving image quality.

[0194] In some examples, refer to Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the end of the magnetic core 122 facing the second magnetic shielding cover 15 may be provided with a fourth chamfer 1222.

[0195] It is understood that in some examples of the embodiments of this application, the setting method of the fourth chamfer 1222 may be the same as, similar to or similar to the third chamfer 1221. For details, please refer to the detailed description of the third chamfer 1221. The embodiments of this application will not repeat this description.

[0196] In some examples, the angle of either the third chamfer 1221 or the fourth chamfer 1222 can be between 0° and 75°.

[0197] In some examples, the angle of the third chamfer 1221 can be 0° to 75°.

[0198] In some examples, refer to Figures 5-7 As shown, the third chamfer 1221 can refer to the angle β between the inner wall of the magnetic core 122 and the inclined surface of the chamfer after the magnetic core 122 is chamfered.

[0199] In some examples, the angle of the third chamfer 1221 can be 15° to 75°.

[0200] In some examples, the angle of the third chamfer 1221 can be 20°.

[0201] In some examples, the angle of the fourth chamfer 1222 can be 0° to 75°.

[0202] In some examples, the angle of the fourth chamfer 1222 can be 20° to 75°.

[0203] In some examples, the angle of the fourth chamfer 1222 can be 60°.

[0204] In some examples of embodiments of this application, the angles of the third chamfer 1221 and the fourth chamfer 1222 are set to 0°~75°. This optimizes the magnetic field transition between the magnetic core 122 and the magnetic shielding covers (first magnetic shielding cover 14 and second magnetic shielding cover 15), reduces magnetic field concentration at the end of the magnetic core 122, minimizes abrupt changes in the magnetic field at the end of the magnetic deflection component 12, improves the matching between the end magnetic field and the electric field, reduces electron beam drift at the end of the Wien filter 10, and improves image clarity and contrast, thereby enhancing image quality.

[0205] In some examples, refer to Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the cut-off dimension of the third chamfer 1221 can be the fifth dimension L5.

[0206] In some examples, the fifth dimension L5 can be 2mm to 3mm.

[0207] In some examples, the fifth dimension L5 can be 2.5mm.

[0208] In some examples, along the axial direction of the magnetic shielding cylinder 13, the size of the protruding magnetic support 121 of the magnetic core 122 can be the sixth dimension L6. This facilitates the winding of the coil on the magnetic support 121, avoids the coil protruding from the magnetic core 122 after winding, and provides sufficient winding space for the coil.

[0209] In some examples, the sixth dimension L6 can be 5mm to 7mm.

[0210] In some examples, the sixth dimension L6 can be 6mm.

[0211] In some examples, the fifth dimension L5 can be less than or equal to two-thirds of the sixth dimension L6.

[0212] In some examples of embodiments of this application, along the axial direction of the magnetic shielding cylinder 13, the cut-off size of the third chamfer 1221 is set to the fifth size L5, and the size of the magnetic core 122 protruding from the magnetic support 121 is set to the sixth size L6; and the fifth size L5 is set to be less than two-thirds of the sixth size L6. Thus, in the magnetic field transition region between the magnetic core 122 and the first magnetic shielding cover 14, controlling the cut-off size of the third chamfer 1221 to within two-thirds of the sixth size L6 reduces the concentration of the magnetic field at the end of the magnetic core 122, making the transition of the magnetic field from the main body of the magnetic core 122 to the first magnetic shielding cover 14 more linear. This effectively avoids irregular deflection of the electron beam due to sudden changes in the magnetic field when entering or leaving the Wien filter 10, ensuring the stability of the electron beam trajectory. Secondly, the sixth dimension L6 of the magnetic core 122 protruding from the magnetic support 121 provides ample space for coil winding. The design of L5 being less than two-thirds of L6 not only avoids compressing the winding range of the coil, but also allows the inclined surface of the third chamfer 1221 to maintain a reasonable distance from the end of the coil, reducing the interference of the coil's magnetic field on the magnetic field at the end of the magnetic core 122.

[0213] In some examples, refer to Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the cut-off dimension of the fourth chamfer 1222 can be the seventh dimension L7.

[0214] In some examples, the seventh dimension can be 0.5mm to 1.5mm.

[0215] In some examples, the seventh dimension can be 1 mm.

[0216] In some examples, the magnetic core 122 protrudes from the magnetic support 121 by an eighth dimension L8 along the axial direction of the magnetic shielding cylinder 13. This facilitates the winding of the coil on the magnetic support 121, avoids the coil protruding from the magnetic core 122 after winding, and provides sufficient winding space for the coil.

[0217] In some examples, the eighth dimension L8 can be 3mm to 5mm.

[0218] In some examples, the eighth dimension L8 can be 4mm.

[0219] In some examples, the seventh dimension L7 can be less than two-thirds the size of the eighth dimension L8.

[0220] Figure 8 This is another simplified top view of the Wien filter in an electron beam imaging device provided in some embodiments of this application. Figure 9 This is another simplified top view of the Wien filter in the electron beam imaging device provided in some embodiments of this application.

[0221] In some examples, refer to Figure 8and Figure 9 As shown, along the radial direction of the magnetic shielding cylinder 13, the cross-sectional shape of the magnetic core 122 can be a first sector ring. That is, the magnetic pole pair can be an arc-shaped magnetic pole pair.

[0222] In some examples, multiple first sector rings can be arranged in a common circle. For example, magnetic pole pairs can be arranged in a common circle.

[0223] In some examples, refer to Figure 8 As shown, the magnetic deflection component 12 may include at least one set of magnetic pole pairs. Multiple sets of magnetic pole pairs may be arranged opposite each other along the radial direction of the magnetic shielding cylinder 13.

[0224] In some examples, refer to Figure 8 As shown, the central angle corresponding to the first sector ring can be the first central angle a1. The first central angle a1 can be 15°~160°.

[0225] In some examples, refer to Figure 8 As shown, the magnetic deflection component 12 may include a set of magnetic pole pairs. When the magnetic deflection component 12 includes a set of magnetic pole pairs, the first central angle α1 may be 20° to 160°. For example, the first central angle α1 may be 40° to 140°. Alternatively, the first central angle α1 may be 60° to 120°.

[0226] In some examples, when the magnetic deflection component 12 includes a set of magnetic pole pairs, the pole pairs can be arranged radially symmetrically with respect to the magnetic shielding cylinder 13. Additionally, the magnetic core 122 and the magnetic support 121 can be arranged radially symmetrically with respect to another aspect of the magnetic shielding cylinder 13. Furthermore, the respective axes of symmetry of the magnetic pole pairs can coincide. That is, the two magnetic cores 122 can be symmetrical along the same axis of symmetry.

[0227] In some examples, the magnetic field strength and the uniformity range of the magnetic field can be controlled by adjusting the size of the first central angle corresponding to the magnetic core 122.

[0228] In some examples, refer to Figure 8 As shown, for ease of explanation, the two magnetic cores 122 in a pair of magnetic poles can be referred to as the first magnetic core 1223 and the second magnetic core 1224, respectively. To facilitate the magnetic field provided by the magnetic deflection component 12, a current I can be passed through the coil corresponding to the first magnetic core 1223. For example, a positive current +I can be passed through the coil corresponding to the first magnetic core 1223. Similarly, a current I can be passed through the coil corresponding to the second magnetic core 1224. For example, a negative current -I can be passed through the coil corresponding to the second magnetic core 1224.

[0229] In other words, equal and opposite currents can be passed through the coils corresponding to the first magnetic core 1223 and the second magnetic core 1224, respectively, to obtain currents along... Figure 8 The magnetic field is in the direction indicated by the x-axis.

[0230] In some examples, refer to Figure 9 As shown, the magnetic deflection component 12 may include multiple sets of magnetic pole pairs. Among them, Figure 9 The example is shown with two pairs of magnetic poles.

[0231] In some examples, for ease of explanation, the magnetic cores 122 corresponding to multiple sets of magnetic pole pairs can be named as first magnetic core 1223, second magnetic core 1224, third magnetic core 1225 and fourth magnetic core 1226, respectively.

[0232] In some examples, when the magnetic deflection component 12 includes two sets of magnetic pole pairs, refer to Figure 9 As shown, the first central angle a1 can be 15°~75°.

[0233] In some examples, the first central angle a1 can be 30° to 60°.

[0234] In some examples, to facilitate the generation of a magnetic field by the magnetic deflection component 12, a positive current +I can be passed through the coils corresponding to the first magnetic core 1223 and the second magnetic core 1224, respectively, and a negative current -I can be passed through the third magnetic core 1225 and the fourth magnetic core 1226, respectively, thereby obtaining a magnetic field along the direction of magnetic deflection. Figure 9 The magnetic field is in the direction indicated by the y-axis.

[0235] In some examples of embodiments of this application, along the radial direction of the magnetic shielding cylinder 13, the cross-sectional shape of the magnetic core 122 is set as a first sector ring, multiple first sector rings are arranged circumferentially, and the central angle corresponding to the first sector ring is set as a first central angle, which is 15°~160°. Thus, the first central angle range of 15°~160° is easily adjustable, thereby controlling the effective magnetic conductive area of ​​the magnetic core 122 and improving the coverage and intensity of the magnetic field. Furthermore, the arrangement of multiple first sector rings circumferentially allows the magnetic fields generated by each magnetic core 122 to form a continuous and uniform superposition effect in the circumferential direction, ensuring that the electron beam is always subjected to a stable and controllable deflection force when passing through the magnetic deflection region, thus improving the clarity and stability of electron beam imaging.

[0236] In some examples, refer to Figure 9 As shown, the included angle between the angle bisectors of adjacent first sector rings can be the second central angle a2. The second central angle a2 can be 15° to 165°. For example, the second central angle can be 30° to 150°. Alternatively, the second central angle can be 60° to 120°.

[0237] In some examples, the angle bisector of the central angle corresponding to the first sector ring can be the axis of symmetry of the first sector ring. That is, in some examples of embodiments of this application, the included angle between the axes of symmetry of two adjacent first sector rings can be the first central angle α2.

[0238] In some examples, the first central angle a1 can be smaller than the second central angle a2.

[0239] In some examples, the sum of the first central angle a1 and the second central angle a2 can be less than 180°.

[0240] In some examples of embodiments of this application, the included angle between the angle bisectors of adjacent first sector rings is set as the second central angle a2, and the second central angle a2 is set to 15°~165°; and the first central angle a1 is smaller than the second central angle a2, and the sum of the first central angle a1 and the second central angle a2 is less than 180°. Thus, by setting the second central angle a2 to 15°~165°, and the first central angle a1 being smaller than the second central angle a2, and the sum of the first central angle a1 and the second central angle a2 being less than 180°, it is possible to ensure that each first sector ring has sufficient magnetic field coverage to provide adequate force for electron beam deflection, and through the reasonable arrangement of multiple sector rings, precise control of the magnetic field strength can be achieved within a limited magnetic deflection area. Furthermore, this angle design can optimize the space utilization of the magnetic deflection area, improving the deflection efficiency of the Wien filter 10 for the electron beam without increasing the overall size of the device, providing strong support for the miniaturization and high performance of electron beam imaging equipment.

[0241] In some examples, refer to Figure 8 and Figure 9 As shown, the size of the magnetic support 121 along the axial direction of the magnetic shielding cylinder 13 can be D1.

[0242] In some examples, one-eighth of the chord length corresponding to the first fan ring can be less than D1. Alternatively, D1 can be less than one-half of the chord length corresponding to the first fan ring.

[0243] In some examples, refer to Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the dimension between the magnetic support 121 and the first magnetic shielding cover 14 can be 9mm to 11mm. For example, the dimension between the magnetic support 121 and the first magnetic shielding cover 14 can be 10mm. This ensures that the magnetic support 121 has sufficient winding space.

[0244] In some examples, refer to Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the dimension between the magnetic support 121 and the second magnetic shielding cover 15 can be 9mm to 11mm. For example, the dimension between the magnetic support 121 and the second magnetic shielding cover 15 can be 10mm. This ensures that the magnetic support 121 has sufficient winding space.

[0245] In some examples, the outer diameter of the circumference of the first sector ring can be 42mm to 46mm. For example, the outer diameter of the circumference of the first sector ring can be 44mm.

[0246] In some examples, the inner diameter of the circumference of the first sector ring can be 34mm to 38mm. For example, the inner diameter of the circumference of the first sector ring can be 36mm.

[0247] In some examples, refer to Figures 5-7 As shown, the electrical deflection component 11 may include an insulating support 111. The insulating support 111 may be connected to at least one of the first magnetic shielding cover 14 and the second magnetic shielding cover 15.

[0248] In some examples, the insulating support 111 may be connected to the first magnetic shielding cover 14.

[0249] In some examples, the insulating support 111 may be connected to the second magnetic shielding cover 15.

[0250] In some examples, the insulating support 111 can be a ceramic cylinder. The insulating support 111 can be a hollow cylinder or a T-shaped hollow cylinder.

[0251] In some examples, the insulating support 111 can be connected to at least one of the first magnetic shielding cover 14 and the second magnetic shielding cover 15 by means of screws, bolts or threaded rods.

[0252] In some examples, the outer diameter of the insulating support 111 may be smaller than the inner diameter of the magnetic deflection component 12.

[0253] In some examples, the size of the insulating support 111 along the axial direction of the magnetic shielding cylinder 13 may be smaller than the size of the magnetic shielding cylinder 13.

[0254] In some examples, the insulating support 111 can be made of a low-permeability material. This low-permeability material can be one with a permeability less than 1.5. For example, the insulating support 111 can be made of a low-permeability, insulating material such as ceramic or PEEK.

[0255] In some examples, refer to Figures 5-7 As shown, the electrical deflection component 11 may include an electrode plate 112. The electrode plate 112 may be connected to the insulating support member 111.

[0256] In some examples, the electrode plates 112 can be arranged in pairs. That is, the magnetic deflection component 12 can include at least one set of paired electrode plates 112.

[0257] In some examples, refer to Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the end of the electrode plate 112 facing the first magnetic shielding height may be provided with a fifth chamfer 1121.

[0258] It is understood that in some examples of the embodiments of this application, the setting method of the fifth chamfer 1121 may be the same as, similar to or similar to the setting method of the first chamfer 1411 in the foregoing embodiments of this application. For details, please refer to the detailed description of the foregoing embodiments of this application. The embodiments of this application will not repeat the details here.

[0259] In some examples of embodiments of this application, the electrode plate 112 is connected to the insulating support 111 via an insulating support 111 connected to at least one of the first magnetic shielding cover 14 and the second magnetic shielding cover 15. Furthermore, along the axial direction of the magnetic shielding cylinder 13, a fifth chamfer 1121 is provided at the first end of the electrode plate 112 facing the first magnetic shielding cover 14. Thus, the fifth chamfer 1121 effectively reduces the electric field concentration at the edge of the electrode plate 112, avoiding partial discharge problems caused by excessively high electric field strength, and improving the stability and safety of the electric deflection component 11 during operation. In addition, the fifth chamfer 1121 reduces the electric field component at the end of the electric deflection component 11 along the axial direction of the magnetic shielding cylinder 13, causing the electric field to decrease gradually at the end of the electric deflection component 11. This improves the matching between the electric and magnetic fields, thereby reducing the risk of electron beam drift at the axial end of the Wien filter 10, increasing the reception rate of the secondary electron detector 20 for secondary electrons, improving the clarity and contrast of the image, and enhancing the image quality.

[0260] In some examples, the inner diameter of the insulating support 111 may be the same as, similar to or similar to the outer diameter of the electrically deflecting component 11.

[0261] In some examples, the outer diameter of the insulating support 111 can be 28 mm to 32 mm. For example, the outer diameter of the insulating support 111 can be 30 mm.

[0262] In some examples, refer to Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the end of the electrode plate 112 facing the second magnetic shielding cover 15 may be provided with a sixth chamfer 1122.

[0263] In some examples, the setting of the sixth chamfer 1122 may be the same as, similar to or similar to the fifth chamfer 1121. For details, please refer to the detailed description of the fifth chamfer 1121 in the foregoing embodiments of this application. This application will not repeat the details in the embodiments.

[0264] In some examples, the angle of either the fifth chamfer 1121 or the sixth chamfer 1122 can be between 0° and 45°.

[0265] In some examples, the angle of the fifth chamfer 1121 can be 0° to 45°.

[0266] In some examples, refer to Figure 5As shown, after a fifth chamfer 1121 is formed on the electrode plate 112, a bevel is formed at the end of the electrode plate 112. The fifth chamfer 1121 can refer to the acute angle b1 formed between the inner wall of the electrode plate 112 and the bevel.

[0267] In some examples, the fifth chamfer 1121 can be 15° to 30°. For example, the fifth chamfer 1121 can be 25°.

[0268] In some examples, the sixth chamfer 1122 can be 0° to 45°.

[0269] In some examples, the sixth chamfer 1122 can be 15° to 30°. For example, the sixth chamfer 1122 can be 20°.

[0270] In some examples of embodiments of this application, the angle of either the fifth chamfer 1121 or the sixth chamfer 1122 is set to 0°~45°. Thus, the bevels of the fifth chamfer 1121 and the sixth chamfer 1122 at the axial end of the electrode plate 112 can optimize the electric field distribution at the end of the electrode plate 112, reduce electric field distortion caused by charge concentration at the edge of the electrode plate 112, improve the matching between the electric field and magnetic field at the axial end of the Wien filter 10, and thereby improve the deflection accuracy and focusing effect of the Wien filter 10 on the electron beam.

[0271] In some examples, refer to Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the cut-off dimension of either the fifth chamfer 1121 or the sixth chamfer 1122 can be the ninth dimension L9.

[0272] In some examples, the cut-off dimension of the fifth chamfer 1121 along the axial direction of the magnetic shielding cylinder 13 can be L9. The cut-off dimension of the fifth chamfer 1121 can be 8mm to 10mm. For example, the cut-off dimension of the fifth chamfer 1121 can be 9mm.

[0273] In some examples, the cut-off dimension of the sixth chamfer 1122 along the axial direction of the magnetic shielding cylinder 13 can be L9. The cut-off dimension of the sixth chamfer 1122 can be 5mm to 7mm. For example, the cut-off dimension of the sixth chamfer 1122 can be 6mm.

[0274] In some examples, refer to Figures 5-7 As shown, along the axial direction of the magnetic shielding cylinder 13, the size of the electrode plate 112 can be the tenth dimension L10.

[0275] In some examples, the tenth dimension L10 can be 28mm to 32mm. For example, the tenth dimension can be 30mm.

[0276] In some examples, the ninth dimension L9 can be less than one-third the size of the tenth dimension L10.

[0277] In some examples of embodiments of this application, along the axial direction of the magnetic shielding cylinder 13, the cutting dimension of either the fifth chamfer 1121 or the sixth chamfer 1122 of the electrode plate 112 is set as the ninth dimension, and the dimension of the electrode plate 112 is set as the tenth dimension; wherein, the ninth dimension is less than one-third of the tenth dimension. Thus, the ninth dimension being less than one-third of the tenth dimension reduces the occupancy of the ninth dimension on the entire electrode plate 112, facilitating the formation of a uniform electric field between the electrode pairs, and gradually reducing the electric field strength at both ends of the electrode plate 112 along the axial direction, facilitating the matching of the electric and magnetic fields at both ends of the Wien filter 10.

[0278] Furthermore, in some examples of embodiments of this application, the first magnetic shielding cover 14 and the second magnetic shielding cover 15 serve as conductors, and can act as natural electric field boundaries. That is, regardless of whether the Wien filter 10 is grounded or connected to a high voltage, the electric field strength along the axial direction of the Wien filter 10 decreases to 0 V / m at the first magnetic shielding cover 14 and the second magnetic shielding cover 15. In some examples of embodiments of this application, the first magnetic shielding cover 14 and the second magnetic shielding cover 15 are made of highly permeable materials, and the highly permeable first magnetic shielding cover 14 and the second magnetic shielding cover 15 can also act as magnetic field boundaries, and the axial magnetic induction intensity of the Wien filter 10 also decreases to 0 T at the first magnetic shielding cover 14 and the second magnetic shielding cover 15. Therefore, along the axial direction of the Wien filter 10, the first magnetic shielding cover 14 and the second magnetic shielding cover 15 can ensure that the axial magnetic field does not change abruptly and the axial electric field strength is stable at 0. This facilitates the adjustment of the matching between the axial magnetic field and the axial electric field, reduces the drift of the electron beam during its entry into or exit from the Wien filter 10, improves the clarity and contrast of the image, and enhances the image quality.

[0279] In some examples, refer to Figure 8 and Figure 9 As shown, along the radial direction of the magnetic shielding cylinder 13, the cross-sectional shape of the electrode plate 112 can be a second sector ring. Multiple second sector rings are distributed circumferentially. That is, in some examples of embodiments of this application, the electrical deflection component 11 may include at least one set of arc-shaped electrode pairs. Figure 8 and Figure 9 The electric deflection component 11 includes two sets of arc-shaped electrode pairs, which are illustrated as an example.

[0280] In some examples, the center of the second sector ring may coincide with the center of the first sector ring.

[0281] In some examples, refer to Figure 8 and Figure 9As shown, the central angle corresponding to the second sector ring can be the second central angle a3. The second central angle a3 can be 15°~75°. For example, the second central angle a3 can be 30°~60°; or, the second central angle a3 can be 45°.

[0282] In some examples, for ease of illustration, ... Figure 8 and Figure 9 The two sets of electrodes are used as examples for illustration. The electrode plates 112 can be named as the first electrode plate 1123, the second electrode plate 1124, the third electrode plate 1125, and the fourth electrode plate 1126, respectively.

[0283] In some examples, with Figure 9 As an example, along Figure 9 The two electrode plates 112 arranged in the x-direction and located in the positive y-direction can be the first electrode plate 1123 and the second electrode plate 1124, wherein the first electrode plate 1123 can be located to the left of the second electrode plate 1124. The two electrode plates 112 located in the negative y-direction can be the third electrode plate 1125 and the fourth electrode plate 1126, wherein the fourth electrode plate 1126 can be located to the left of the third electrode plate 1125. That is to say, the first electrode plate 1123, the second electrode plate 1124, the third electrode plate 1125, and the fourth electrode plate 1126 can be arranged along the x-direction. Figure 9 The electrodes are arranged in a clockwise direction in a circular pattern. It can be understood that the first electrode plate 1123, the second electrode plate 1124, the third electrode plate 1125, and the fourth electrode plate 1126 can be arranged at even intervals.

[0284] In some examples, to facilitate the generation of an electric field by the electric deflection component 11, a negative voltage of magnitude v can be applied to the first electrode plate 1123 and the fourth electrode plate 1126, i.e., the voltage on the first electrode plate 1123 and the fourth electrode plate 1126 is -v; alternatively, a positive voltage of magnitude v can be applied to the second electrode plate 1124 and the third electrode plate 1125, i.e., the voltage on the second electrode plate 1124 and the third electrode plate 1125 can be +v; thus, the electric deflection component 11 can generate an electric field along... Figure 9 The electric field pointing towards the negative x-axis. This makes... Figure 9 The electric and magnetic fields are orthogonal.

[0285] It is understood that in some examples of the embodiments of this application, the magnitude and specific polarity of the voltage on the first electrode plate 1123, the second electrode plate 1124, the third electrode plate 1125 and the fourth electrode plate 1126 can be adjusted according to the magnitude and direction of the magnetic field generated by the magnetic deflection component 12.

[0286] In some examples of embodiments of this application, the cross-sectional shape of the electrode plate 112 is set as a second sector ring along the radial direction of the magnetic shielding cylinder 13, with multiple second sector rings distributed circumferentially; and the second central angle corresponding to the second sector ring is set to 15°~75°. Thus, the arc-shaped second sector ring can adapt to the cylindrical inner wall of the magnetic shielding cylinder 13, making the gap between the electrode plate 112 and the magnetic shielding cylinder 13 uniform, which can improve the uniformity of the electric field generated by the electric deflection component 11 and improve the stability of the electric field force experienced by the electron beam during deflection. Furthermore, setting the second central angle to 15°~75° allows for the adjustment of the uniformity range of the electric field by controlling the angle of the second central angle, and facilitates the adjustment of the angle between the electric and magnetic fields by controlling the relative angle between the electrode plate 112 and the magnetic core 122. This improves the matching of the electric and magnetic fields.

[0287] In some examples, the inner diameter of the electric deflection component 11 can be 8 mm to 10 mm. For example, the inner diameter of the electric deflection component 11 can be 9 mm.

[0288] In some examples, the outer diameter of the electrically deflecting component 11 can be 18 mm to 22 mm. For example, the outer diameter of the electrically deflecting component 11 can be 20 mm.

[0289] Figure 10 This is another simulation curve of the electric field and magnetic field matching degree of the Wien filter in the electron beam imaging device provided in some embodiments of this application.

[0290] In some examples, refer to Figure 10 As shown, Figure 10 The solid line e represents the distribution curve of the electric field along the axial direction of the Wien filter 10; Figure 10 The dashed line f represents the distribution curve of the magnetic field along the axial direction of the Wien filter 10. The horizontal axis represents the axial dimension along the Wien filter 10, and the vertical axis represents the intensity of the electric and magnetic fields. Figure 10 As can be seen, in some examples of the embodiments of this application, after using the Wien filter 10 described in detail in the foregoing embodiments of this application, the magnetic field generated by the magnetic deflection component 12 will not leak to both ends of the Wien filter 10 along the axis, and the magnetic field and electric field have a high degree of matching and consistency, which improves the uniformity of the force on the electron beam in the Wien filter 10, reduces the drift of the electron beam during the process of entering or leaving the Wien filter 10, and can improve the clarity and contrast of the image, thus improving the image quality.

[0291] Figure 11 These are comparison images of sample test images obtained by an electron beam imaging device provided in some embodiments of this application with test images in related technologies.

[0292] In some examples, refer to Figure 11 As shown, Figure 11In the image, g represents the image of the sample being tested using an electron beam imaging device in the relevant technology. Figure 11 Image h is an image of a sample tested using an electron beam imaging device provided in some embodiments of this application. It can be seen that by using the electron beam imaging device provided in some embodiments of this application to test the sample, the secondary electron detector 20 increases the reception rate of secondary electrons, thereby improving image contrast and clarity, and enhancing imaging quality.

[0293] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0294] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A Wien filter, characterized in that, include: An electric deflection component (11) is arranged circumferentially and generates an electric field in a first direction; A magnetic deflection component (12) is coaxially arranged with the electric deflection component (11) and located on the outer periphery of the electric deflection component (11). The magnetic deflection component (12) generates a magnetic field along a second direction, which is orthogonal to the first direction. A magnetic shielding cylinder (13) is sleeved on the outer periphery of the magnetic deflection component (12); The first magnetic shielding cover (14) is located along the axial direction of the magnetic shielding cylinder (13), at the first end of the magnetic shielding cylinder (13), and at one end of the axial direction of the magnetic deflection component (12). The second magnetic shielding cover (15) is located along the axial direction of the magnetic shielding cylinder (13) at the second end of the magnetic shielding cylinder (13) and at the other end of the axial direction of the magnetic deflection component (12).

2. The Wien filter according to claim 1, characterized in that, The first magnetic shielding cover (14) is provided with a first magnetic shielding screw, which connects the first magnetic shielding cover (14) and the magnetic shielding cylinder (13); The second magnetic shielding cover (15) is provided with a second magnetic shielding screw, which connects the second magnetic shielding cover (15) to the magnetic shielding cylinder (13).

3. The Wien filter according to claim 1, characterized in that, The first magnetic shielding cover (14) has a first central shaft hole (141), which is coaxial with the magnetic shielding cylinder (13); The second magnetic shielding cover (15) has a second central shaft hole (151), which is coaxial with the first central shaft hole (141); The radial dimension of either the first central shaft hole (141) or the second central shaft hole (151) is less than or equal to the inner diameter of the magnetic deflection component (12).

4. The Wien filter according to claim 3, characterized in that, The first central shaft hole (141) has a first chamfer (1411) at one end facing the magnetic deflection component (12); And / or, The second central shaft hole (151) has a second chamfer (1511) at one end facing the magnetic deflection component (12).

5. The Wien filter according to claim 4, characterized in that, The angle of either the first chamfer (1411) or the second chamfer (1511) is 0° to 60°.

6. The Wien filter according to claim 4, characterized in that, Along the axial direction of the magnetic shielding cylinder (13), the first magnetic shielding cover (14) has a first dimension, and the first chamfer (1411) has a second dimension between the end away from the magnetic deflection component (12) and the side of the first magnetic shielding cover (14) away from the magnetic deflection component (12); the second dimension is smaller than the first dimension and is greater than one-third of the first dimension; And / or, In the axial direction of the magnetic shielding cylinder (13), the second magnetic shielding cover (15) has a third dimension, and the second chamfer (1511) has a fourth dimension between one end away from the magnetic deflection component (12) and the side of the second magnetic shielding cover (15) away from the magnetic deflection component (12); the fourth dimension is smaller than the third dimension and the fourth dimension is greater than one-third of the third dimension.

7. The Wien filter according to any one of claims 1-6, characterized in that, The magnetic deflection component (12) includes: A magnetic support (121) is located inside the magnetic shielding cylinder (13) and is used to wind a coil. A magnetic core (122) is connected to the side of the magnetic support (121) away from the magnetic shielding cylinder (13). Along the axial direction of the magnetic shielding cylinder (13), the end of the magnetic core (122) facing the first magnetic shielding cover (14) is provided with a third chamfer (1221). And / or, Along the axial direction of the magnetic shielding cylinder (13), the magnetic core (122) has a fourth chamfer (1222) at one end facing the second magnetic shielding cover (15).

8. The Wien filter according to claim 7, characterized in that, The angle of either the third chamfer (1221) or the fourth chamfer (1222) is 0° to 75°.

9. The Wien filter according to claim 7, characterized in that, Along the axial direction of the magnetic shielding cylinder (13), the cut-off dimension of the third chamfer (1221) is the fifth dimension; the dimension by which the magnetic core (122) protrudes from the magnetic support (121) is the sixth dimension; the fifth dimension is less than two-thirds of the sixth dimension; And / or, Along the axial direction of the magnetic shielding cylinder (13), the cut-off dimension of the fourth chamfer (1222) is the seventh dimension, and the dimension by which the magnetic core (122) protrudes from the magnetic support (121) is the eighth dimension. The seventh dimension is less than two-thirds of the eighth dimension.

10. The Wien filter according to claim 7, characterized in that, Along the radial direction of the magnetic shielding cylinder (13), the cross-sectional shape of the magnetic core (122) is a first fan ring, and multiple first fan rings are arranged in a circular arrangement. The central angle corresponding to the first fan ring is the first central angle; the first central angle is 15°~160°.

11. The Wien filter according to claim 10, characterized in that, The included angle between the angle bisectors of adjacent first sector rings is the second central angle, which is 15°~165°; wherein, the first central angle is smaller than the second central angle, and the sum of the second central angle and the first central angle is less than 180°.

12. The Wien filter according to any one of claims 1-6, characterized in that, The electrical deflection component (11) includes: An insulating support (111) is connected to at least one of the first magnetic shielding cover (14) and the second magnetic shielding cover (15); Electrode plate (112), the electrode plate (112) is connected to the insulating support (111); along the axial direction of the magnetic shielding cylinder (13), the electrode plate (112) has a fifth chamfer (1121) at one end facing the first magnetic shielding cover (14); and / or, the electrode plate (112) has a sixth chamfer (1122) at one end facing the second magnetic shielding cover (15).

13. The Wien filter according to claim 12, characterized in that, The angle of either the fifth chamfer (1121) or the sixth chamfer (1122) is 0° to 45°.

14. The Wien filter according to claim 12, characterized in that, Along the axial direction of the magnetic shielding cylinder (13), the cut-off dimension of either the fifth chamfer (1121) or the sixth chamfer (1122) is the ninth dimension; the dimension of the electrode plate (112) is the tenth dimension, and the ninth dimension is less than one-third of the tenth dimension.

15. The Wien filter according to claim 12, characterized in that, Along the radial direction of the magnetic shielding cylinder (13), the cross-sectional shape of the electrode plate (112) is a second fan ring; multiple second fan rings are distributed circumferentially; the central angle corresponding to the second fan ring is the second central angle, which is 15°~75°.

16. An electron beam imaging device, characterized in that, include: Secondary electron detector (20); A sample stage (30) and the secondary electron detector (20) are arranged along a third direction; and The Wien filter (10) according to any one of claims 1-15, wherein the Wien filter (10) is located between the sample stage (30) and the secondary electron detector (20), and the Wien filter (10) is coaxial with the electron aperture (21) of the secondary electron detector (20).

Images