Electron beam magnetic lens capable of eliminating aberrations

Abstract

The application relates to the technical field of electron microscopic imaging, and particularly relates to an electron beam magnetic lens capable of eliminating aberration, which comprises a movable diaphragm shell and a ring-shaped shell, and further comprises a mounting assembly; the mounting assembly comprises a cross roller bearing, a movable diaphragm screw bevel gear, a screw bevel gear stand, a diaphragm body, a movable diaphragm circumscribed component, an electromagnetic focusing component and an astigmatism correction component; the cross roller bearing is fixedly connected with the movable diaphragm shell, the movable diaphragm screw bevel gear is fixedly connected with the cross roller bearing, the screw bevel gear stand is fixedly connected with the movable diaphragm screw bevel gear, and the diaphragm body is rotationally connected with the cross roller bearing, so that the adjustable electron beam incident aperture half angle can be realized through the movable aperture diaphragm arranged, the spherical aberration can be eliminated, a plurality of samples can be simultaneously adapted, the electron beam converging effect can be made stronger, the resolution is improved, and the effect is better in actual use.

Description

Technical Field

[0001] This invention relates to the field of electron microscopy imaging technology, and in particular to an electron beam magnetic lens that can eliminate aberrations. Background Technology

[0002] Scanning electron microscopes use an electron beam emitted by an electron gun as the observation source. The electron gun usually consists of a cathode, a focusing electrode, and an anode. A magnetic lens can generate an axisymmetric non-uniform magnetic field. The electron beam is focused into a point on the sample surface through the magnetic lens. The resolution of the microscope is affected by the radius of the focused beam spot.

[0003] However, using the above method, the overall practical effect of eliminating spherical aberration and adapting to various samples in the existing electron beam magnetic lens operation is not ideal, which will affect the final image quality in actual use. Summary of the Invention

[0004] The purpose of this invention is to provide an electron beam magnetic lens that can eliminate aberrations. The half-angle of the electron beam incident aperture can be adjusted by a movable aperture stop, which is beneficial for eliminating spherical aberration and adapting to various samples. At the same time, it can also strengthen the electron beam focusing effect, improve resolution, and make the effect better in actual use.

[0005] To achieve the above objectives, the present invention provides an electron beam magnetic lens capable of eliminating aberrations, comprising a movable aperture housing and an annular housing, wherein the movable aperture housing is connected to the annular housing, and further comprising a mounting assembly;

[0006] The mounting assembly includes a crossed roller bearing, a movable aperture spiral bevel gear, a spiral bevel gear column, an aperture body, a movable aperture external component, an electromagnetic focusing component, and an astigmatism correction component. The crossed roller bearing is fixedly connected to the movable aperture housing and located on one side of the movable aperture housing. The movable aperture spiral bevel gear is fixedly connected to the crossed roller bearing and located on one side of the crossed roller bearing. The spiral bevel gear column is fixedly connected to the movable aperture spiral bevel gear and located on one side of the movable aperture spiral bevel gear. The aperture body is rotatably connected to the crossed roller bearing and located on the side of the crossed roller bearing near the spiral bevel gear column. The movable aperture external component is connected to the movable aperture housing. The electromagnetic focusing component is connected to the annular housing. The astigmatism correction component is located on one side of the annular housing.

[0007] The movable aperture external component includes a spiral bevel gear shaft, a fine-tuning knob, a connecting component, and a sealing component. The spiral bevel gear shaft is connected to the movable aperture housing via the connecting component and meshes with the spiral bevel gear of the movable aperture. The fine-tuning knob is connected to the spiral bevel gear shaft and is located on one side of the spiral bevel gear shaft. The connecting component is connected to the movable aperture housing. The sealing component is connected to the spiral bevel gear shaft.

[0008] The connecting components include a movable aperture external flange and a side bushing. The movable aperture external flange is rotatably connected to the spiral bevel gear shaft and is installed on one side of the movable aperture housing. The side bushing is connected to the movable aperture external flange and is sleeved on the spiral bevel gear shaft.

[0009] The sealing component includes a sealing threaded sleeve, a spacer, and an O-ring. The sealing threaded sleeve is threadedly connected to the external flange of the movable aperture and is fitted onto the spiral bevel gear shaft. The spacer is connected to the external flange of the movable aperture and is fitted onto the spiral bevel gear shaft. The O-ring is connected to the external flange of the movable aperture and is fitted onto the spiral bevel gear shaft.

[0010] The electromagnetic focusing component includes a magnetic circuit coil housing, a magnetic circuit coil upper cover plate, a magnetic circuit coil lower cover plate, a pole shoe component, and a sleeve component. The magnetic circuit coil housing is connected to the annular housing and is located inside the annular housing; the magnetic circuit coil upper cover plate is connected to the magnetic circuit coil housing and is located inside the annular housing; the magnetic circuit coil lower cover plate is connected to the magnetic circuit coil housing and is located inside the annular housing; the pole shoe component is connected to the magnetic circuit coil upper cover plate; and the sleeve component is connected to the magnetic circuit coil housing.

[0011] The pole shoe component includes an upper pole shoe and a lower pole shoe. The upper pole shoe is connected to the upper cover plate of the magnetic circuit coil and is located on one side of the upper cover plate of the magnetic circuit coil. The lower pole shoe is connected to the lower cover plate of the magnetic circuit coil and is located on one side of the lower cover plate of the magnetic circuit coil.

[0012] The sleeve component includes a coil frame and a coil body. The coil frame is connected to the outer shell of the magnetic circuit coil and is located inside the outer shell of the magnetic circuit coil. The coil body is connected to the coil frame and is located on one side of the coil frame.

[0013] The astigmatism correction component includes a threaded connecting platform, an astigmatism correction component frame, and a winding component. The threaded connecting platform is threadedly connected to the lower cover of the magnetic circuit coil and is located on one side of the lower cover plate of the magnetic circuit coil. The astigmatism correction component frame is fixedly connected to the threaded connecting platform and is located on one side of the threaded connecting platform. The winding component is connected to the astigmatism correction component frame.

[0014] The winding component includes a winding post and a winding coil. The winding component is connected to the astigmatism correction component frame and is located on one side of the astigmatism correction component frame. The astigmatism correction component frame is connected to the winding post and is sleeved on the winding post.

[0015] This invention discloses an electron beam magnetic lens capable of eliminating aberrations. The operator can directly rotate the fine-tuning knob, which transmits torque through the spiral bevel gear shaft to the movable aperture spiral bevel gear. The movable aperture spiral bevel gear is fixed to the outer ring of the crossed roller bearing. The end face of the movable aperture spiral bevel gear has eight spiral bevel gear posts made of a low-friction Teflon material. The aperture body is designed with corresponding aperture slots, and the eight slots on the aperture body and the eight spiral bevel gear posts are clearance-fitted. When the movable aperture spiral bevel gear rotates clockwise... At the same time, the eight spiral bevel gear columns move on the slot, pushing the eight aperture bodies to perform an opening movement to enlarge the aperture diameter, and conversely, to reduce the aperture diameter. The aperture diameter adjustment range through the sliding groove movement is 2-20mm. Then, through the electromagnetic focusing component, the magnetic field range of the magnetic lens is made more concentrated, and the electron beam focusing effect is strengthened. This allows the half angle of the electron beam incident aperture to be adjusted through the movable aperture aperture, which is beneficial for eliminating spherical aberration and adapting to various samples, while also strengthening the electron beam focusing effect and improving resolution, resulting in better performance in actual use. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0017] Figure 1 This is a schematic diagram of the overall structure of the aberration-eliminating electron beam magnetic lens according to the first embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the disassembly structure of the annular outer shell according to the first embodiment of the present invention.

[0019] Figure 3 This is a schematic diagram of the installation structure of the aperture body according to the first embodiment of the present invention.

[0020] Figure 4 This is a schematic diagram of the aperture body being fully opened according to the first embodiment of the present invention.

[0021] Figure 5 This is a schematic diagram of the sealing component according to the first embodiment of the present invention.

[0022] Figure 6This is a cross-sectional view of the electron beam magnetic lens capable of eliminating aberrations according to the second embodiment of the present invention.

[0023] Figure 7 This is a schematic diagram of the disassembly of the magnetic circuit coil housing according to the second embodiment of the present invention.

[0024] Figure 8 This is a schematic diagram of the astigmatism correction component frame according to the third embodiment of the present invention.

[0025] Figure 9 This is a cross-sectional view of the electron beam magnetic lens capable of eliminating aberrations according to the third embodiment of the present invention.

[0026] In the diagram: 101-Modible aperture housing, 102-Annular housing, 103-Crossed roller bearing, 104-Modible aperture spiral bevel gear, 105-Spiral bevel gear column, 106-Aperture body, 107-Spiral bevel gear shaft, 108-Fine adjustment knob, 109-Modible aperture external flange, 110-Side bushing, 111-Sealing threaded sleeve, 112-Spacer ring, 113-O-ring, 201-Magnetic circuit coil housing, 202-Magnetic circuit coil upper cover plate, 203-Magnetic circuit coil lower cover plate, 204-Upper pole shoe, 205-Lower pole shoe, 206-Coil frame, 207-Coil body, 301-Threaded connection platform, 302-Ascetic astigmatism correction assembly frame, 303-Winding post, 304-Winding coil. Detailed Implementation

[0027] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

[0028] The first embodiment of this application is as follows:

[0029] Please see Figures 1 to 5 ,in Figure 1 This is a schematic diagram of the overall structure of an electron beam magnetic lens that can eliminate aberrations. Figure 2 This is a schematic diagram of the disassembly structure of the annular outer shell 102. Figure 3 This is a schematic diagram of the installation structure of the aperture body 106. Figure 4 This is a schematic diagram of the aperture body 106 when fully open. Figure 5 This is a schematic diagram of the sealing component.

[0030] This invention provides an electron beam magnetic lens capable of eliminating aberrations: it includes a movable aperture housing 101, an annular housing 102, and a mounting assembly. The mounting assembly includes a crossed roller bearing 103, a movable aperture helical bevel gear 104, a helical bevel gear column 105, an aperture body 106, an external movable aperture component, an electromagnetic focusing component, and an astigmatism correction component. The external movable aperture component includes a helical bevel gear shaft 107, a fine-tuning knob 108, a connecting component, and a sealing component. The connecting component includes an external movable aperture flange 109 and a retaining bushing 110. The sealing component includes a sealing threaded sleeve 111, a spacer 112, and an O-ring 113. This solution solves the problem that the overall practical effect of existing electron beam magnetic lenses in eliminating spherical aberration and adapting to various samples is not ideal, which affects the final image quality during actual use.

[0031] In this embodiment, the movable aperture housing 101 is connected to the annular housing 102, and the annular housing 102 and the movable aperture housing 101 can be directly connected and fixed by corresponding bolts.

[0032] The cross roller bearing 103 is fixedly connected to the movable aperture housing 101 and located on one side of the movable aperture housing 101. The movable aperture helical bevel gear 104 is fixedly connected to the cross roller bearing 103 and located on one side of the cross roller bearing 103. The helical bevel gear column 105 is fixedly connected to the movable aperture helical bevel gear 104 and located on one side of the movable aperture helical bevel gear 104. The aperture body 106 is rotatably connected to the cross roller bearing 103 and located on the side of the cross roller bearing 103 near the helical bevel gear column 105. The movable aperture external component is connected to the movable aperture housing 101. The electromagnetic focusing component is connected to the annular housing 102. The astigmatism correction component is located on one side of the annular housing 102. The inner ring of the cross roller bearing 103 is fixed to an annular protrusion inside the movable aperture housing 101. The outer ring of the crossed roller bearing 103 is fixed with the movable aperture spiral bevel gear 104, allowing the movable aperture spiral bevel gear 104 to rotate within the movable aperture housing 101 via the crossed roller bearing 103. Eight aperture bodies 106 are rotatably mounted on the inner ring of the crossed roller bearing 103. Each of the eight aperture bodies 106 has a slot for engaging with the corresponding eight spiral bevel gear columns 105. The eight spiral bevel gear columns 105 are respectively fixedly mounted on the inner ring of the movable aperture spiral bevel gear 104. When the movable aperture spiral bevel gear 104 rotates, the eight spiral bevel gear columns 105 on the movable aperture spiral bevel gear 104 will drive the corresponding aperture bodies 106 to rotate under the guidance of the slots. Thus, the rotation of the eight aperture bodies 106 achieves the purpose of controlling the aperture diameter.

[0033] Secondly, the spiral bevel gear shaft 107 is connected to the movable aperture housing 101 via the connecting component and meshes with the movable aperture spiral bevel gear 104; the fine-tuning knob 108 is connected to the spiral bevel gear shaft 107 and is located on one side of the spiral bevel gear shaft 107; the connecting component is connected to the movable aperture housing 101; the sealing component is connected to the spiral bevel gear shaft 107; the movable aperture external flange 109 is rotatably connected to the spiral bevel gear shaft 107 and is installed on one side of the movable aperture housing 101; the side bushing 110 is connected to the... The movable aperture external flange 109 is connected and sleeved on the spiral bevel gear shaft 107. The sealing threaded sleeve 111 is threadedly connected to the movable aperture external flange 109 and sleeved on the spiral bevel gear shaft 107. The spacer ring 112 is connected to the movable aperture external flange 109 and sleeved on the spiral bevel gear shaft 107. The O-ring rubber ring 113 is connected to the movable aperture external flange 109 and sleeved on the spiral bevel gear shaft 107. The spiral bevel gear shaft 107 is connected to the movable aperture external flange 109 and the retaining sleeve 111. The movable aperture housing 104 is rotatably mounted on one side of the movable aperture housing 101. Simultaneously, the helical tooth platform at the end of the spiral bevel gear shaft 107 meshes with the bevel teeth on the surface of the movable aperture spiral bevel gear 104. When the spiral bevel gear shaft 107 rotates, the movable aperture spiral bevel gear 104 rotates accordingly under the drive of the spiral bevel gear shaft 107, thus completing the drive of the spiral bevel gear shaft 107. An O-ring 113 is embedded in the external flange 109 of the movable aperture. The O-ring 113 is tightened in the groove, causing the movable aperture to... The connection of the external flange 109 can maintain a seal, thereby allowing the movable aperture housing 101 to be in a vacuum state during operation. In a vacuum state, the resistance to electron movement is greatly reduced. The movable aperture housing 101 is outside the normal atmospheric pressure. The fine adjustment knob 108 and the spiral bevel gear shaft 107 are connected by a set screw. The two O-rings 113 complete the rotational dynamic seal. The two O-rings 113 are separated by the spacer 112, and then the sealing sleeve 111 is used to press the O-rings 113 together to improve the overall sealing effect.

[0034] In this embodiment, the aberration-eliminating electron beam magnetic lens allows the operator to directly rotate the fine-tuning knob 108. The rotation of the knob transmits torque through the spiral bevel gear shaft 107 to the movable aperture spiral bevel gear 104. The movable aperture spiral bevel gear 104 is fixed to the outer ring of the crossed roller bearing 103. The end face of the movable aperture spiral bevel gear 104 has eight spiral bevel gear posts 105 made of Teflon material with a low coefficient of friction. The aperture body 106 has corresponding aperture slots. The eight slots on the aperture body 106 and the eight spiral bevel gear posts 105 are in clearance fit. When the movable aperture spiral bevel gear 104... When the movable aperture spiral bevel gear 104 rotates clockwise, the eight spiral bevel gear columns 105 move on the slot, pushing the eight aperture bodies 106 to perform an opening movement to enlarge the aperture diameter. Conversely, rotating clockwise reduces the aperture diameter. The aperture diameter adjustment range via the sliding groove is 2-20mm. Then, the electromagnetic focusing component further concentrates the magnetic field of the magnetic lens, strengthening the electron beam focusing effect. This allows the half-angle of the electron beam incident aperture to be adjusted via the movable aperture aperture, which helps eliminate spherical aberration and adapt to various samples while also strengthening the electron beam focusing effect and improving resolution, resulting in better performance in actual use.

[0035] Second embodiment:

[0036] Please see Figure 6 and Figure 7 , Figure 6 This is a cross-sectional view of the aberration-eliminating electron beam magnetic lens of the second embodiment. Figure 7 This is a schematic diagram of the disassembly of the magnetic circuit coil housing 201 in the second embodiment. The electromagnetic focusing component provided by the present invention includes a magnetic circuit coil housing 201, a magnetic circuit coil upper cover plate 202, a magnetic circuit coil lower cover plate 203, a pole shoe component, and a sleeve component. The pole shoe component includes an upper pole shoe 204 and a lower pole shoe 205. The sleeve component includes a coil frame 206 and a coil body 207.

[0037] The magnetic circuit coil housing 201 is connected to the annular housing 102 and located inside the annular housing 102; the magnetic circuit coil upper cover plate 202 is connected to the magnetic circuit coil housing 201 and located inside the annular housing 102; the magnetic circuit coil lower cover plate 203 is connected to the magnetic circuit coil housing 201 and located inside the annular housing 102; the pole shoe component is connected to the magnetic circuit coil upper cover plate 202; the sleeve component is connected to the magnetic circuit coil housing 201; the upper pole shoe 204 is connected to the magnetic circuit coil upper cover plate 202 and located on one side of the magnetic circuit coil upper cover plate 202; the lower pole shoe 205 is connected to the magnetic circuit coil lower cover plate 203 and located on one side of the magnetic circuit coil lower cover plate 203; the upper pole shoe 204 is connected to the magnetic circuit coil upper cover plate 202 ... The lower pole shoe 204 is connected to the upper cover plate 202 of the magnetic circuit coil and is located on one side of the upper cover plate 202 of the magnetic circuit coil; the lower pole shoe 205 is connected to the lower cover plate 203 of the magnetic circuit coil and is located on one side of the lower cover plate 203 of the magnetic circuit coil. The outer shell 201 of the magnetic circuit coil, the upper cover plate 202 of the magnetic circuit coil, and the lower cover plate 203 of the magnetic circuit coil are all made of high permeability material and have the characteristic of converging magnetic lines of force. When the excitation current flows through the coil, a closed magnetic lens is formed due to the magnetic permeability of the material, and the focusing effect of the electromagnetic lens becomes stronger. The upper pole shoe 204 and the lower pole shoe 205 of the pole shoe assembly are also made of high permeability material. Since the pole shoe extends to the vicinity of the central axis in a conical shape, a more concentrated magnetic field can be formed, thereby improving the resolution of the electromagnetic lens.

[0038] When using an aberration-eliminating electron beam magnetic lens according to this embodiment, the upper cover plate 202 and the lower cover plate 203 of the magnetic circuit coil can be installed through the magnetic circuit coil housing 201. Then, the divergent electron beam is injected into the magnetic field from the top through the upper pole shoe 204 and the lower pole shoe 205. Due to the presence of the conical pole shoe, the magnetic field is concentrated in a very small area. The electron beam is deflected by the Lorentz force after passing through the magnetic field and finally converges to a point, completing the focusing of the electron beam. This makes the magnetic field range more concentrated and greatly enhances the practicality of the entire device.

[0039] Third embodiment:

[0040] Please see Figure 8 and Figure 9 , Figure 8 This is a schematic diagram of the overall structure of the aberration-eliminating electron beam magnetic lens according to the third embodiment. Figure 9 This is a cross-sectional view of the electron beam magnetic lens that can eliminate aberrations according to the third embodiment. The astigmatism correction component provided by the present invention includes a threaded connecting platform 301, an astigmatism correction component frame 302, and a winding component. The winding component includes a winding post 303 and a winding coil 304.

[0041] The threaded connecting platform 301 is threadedly connected to the lower cover of the magnetic circuit coil and is located on one side of the lower cover plate 203 of the magnetic circuit coil; the astigmatism correction component frame 302 is fixedly connected to the threaded connecting platform 301 and is located on one side of the threaded connecting platform 301; the winding component is connected to the astigmatism correction component frame 302 and is located on one side of the astigmatism correction component frame 302; the astigmatism correction component frame 302 is connected to the winding post 303 and is sleeved on the winding post 303; the astigmatism correction component frame 302 is connected to the winding post 303 and is sleeved on the winding post 303. The threaded connection platform 301 is installed below the lower cover of the magnetic circuit coil. Eight sets of winding posts 303 and winding coils 304 are installed on the astigmatism correction component frame 302. The winding posts 303 and winding coils 304 form a column with tubular inner core winding. The winding coils 304 are copper coils. The eight coils of tubular inner core are arranged in an array and installed at the end of the astigmatism correction component frame 302. In this way, a non-uniform magnetic field can be generated by controlling the current flowing into the corresponding winding posts and winding coils 304. Then, the magnetic field generates a corresponding additional force on the electron beam to achieve corresponding adjustment and correction of the electron beam cross-section.

[0042] When using an aberration-eliminating electron beam magnetic lens according to this embodiment, current can be selectively passed into several of the winding coils 304 while current flows out of the other winding coils 304. This generates a non-uniform axial magnetic field on the lens axis. The combined magnetic field of this non-uniform magnetic field exerts an additional force on the electron beam. When the original electron beam has an elliptical cross-section due to astigmatism, the combined magnetic field of the two sets of magnetic fields can correct the astigmatism of the objective lens to an ideal degree by adjusting the strength of the two sets of magnetic fields. For example, if an electron beam affected by astigmatism has an elliptical beam cross-section, coils 1, 2, 5, and 6 form one group, and coils 3, 4, and 7 form another group. Current is applied to the first group of coils, and current is applied to the second group of coils, generating four sets of magnetic fields. Electrons are deflected by the Lorentz force under the influence of each magnetic field. Each set of magnetic fields has a corresponding influence on the direction of electron deflection, ultimately forming the correct electron beam cross-section, greatly enhancing the practicality of the entire device.

[0043] The above-disclosed embodiments are merely one or more preferred embodiments of this application and should not be construed as limiting the scope of this application. Those skilled in the art can understand that all or part of the processes for implementing the above embodiments and equivalent changes made in accordance with the claims of this application still fall within the scope of this application.

Claims

1. An electron beam magnetic lens capable of eliminating aberrations, comprising a movable aperture housing and an annular housing, wherein the movable aperture housing is connected to the annular housing, characterized in that, It also includes installation components; The mounting assembly includes a crossed roller bearing, a movable aperture spiral bevel gear, a spiral bevel gear column, an aperture body, a movable aperture external component, an electromagnetic focusing component, and an astigmatism correction component. The crossed roller bearing is fixedly connected to the movable aperture housing and located on one side of the movable aperture housing. The movable aperture spiral bevel gear is fixedly connected to the crossed roller bearing and located on one side of the crossed roller bearing. The spiral bevel gear column is fixedly connected to the movable aperture spiral bevel gear and located on one side of the movable aperture spiral bevel gear. The aperture body is rotatably connected to the crossed roller bearing and located on the side of the crossed roller bearing near the spiral bevel gear column. The movable aperture external component is connected to the movable aperture housing. The electromagnetic focusing component is connected to the annular housing. The astigmatism correction component is located on one side of the annular housing. The movable aperture external component includes a spiral bevel gear shaft, a fine-tuning knob, a connecting component, and a sealing component. The spiral bevel gear shaft is connected to the movable aperture housing via the connecting component and meshes with the spiral bevel gear of the movable aperture. The fine-tuning knob is connected to the spiral bevel gear shaft and is located on one side of the spiral bevel gear shaft. The connecting component is connected to the movable aperture housing. The sealing component is connected to the spiral bevel gear shaft.

2. The aberration-eliminating electron beam magnetic lens as described in claim 1, characterized in that, The connecting components include a movable aperture external flange and a side bushing. The movable aperture external flange is rotatably connected to the spiral bevel gear shaft and is installed on one side of the movable aperture housing. The side bushing is connected to the movable aperture external flange and is sleeved on the spiral bevel gear shaft.

3. The aberration-eliminating electron beam magnetic lens as described in claim 2, characterized in that, The sealing component includes a sealing threaded sleeve, a spacer, and an O-ring. The sealing threaded sleeve is threadedly connected to the external flange of the movable aperture and is fitted onto the spiral bevel gear shaft. The spacer is connected to the external flange of the movable aperture and is fitted onto the spiral bevel gear shaft. The O-ring is connected to the external flange of the movable aperture and is fitted onto the spiral bevel gear shaft.

4. The aberration-eliminating electron beam magnetic lens as described in claim 1, characterized in that, The electromagnetic focusing component includes a magnetic circuit coil housing, a magnetic circuit coil upper cover plate, a magnetic circuit coil lower cover plate, a pole shoe component, and a sleeve component. The magnetic circuit coil housing is connected to the annular housing and is located inside the annular housing; the magnetic circuit coil upper cover plate is connected to the magnetic circuit coil housing and is located inside the annular housing; the magnetic circuit coil lower cover plate is connected to the magnetic circuit coil housing and is located inside the annular housing; the pole shoe component is connected to the magnetic circuit coil upper cover plate; and the sleeve component is connected to the magnetic circuit coil housing.

5. The aberration-eliminating electron beam magnetic lens as described in claim 4, characterized in that, The pole shoe component includes an upper pole shoe and a lower pole shoe. The upper pole shoe is connected to the upper cover plate of the magnetic circuit coil and is located on one side of the upper cover plate of the magnetic circuit coil. The lower pole shoe is connected to the lower cover plate of the magnetic circuit coil and is located on one side of the lower cover plate of the magnetic circuit coil.

6. The aberration-eliminating electron beam magnetic lens as described in claim 4, characterized in that, The sleeve component includes a coil frame and a coil body. The coil frame is connected to the outer shell of the magnetic circuit coil and is located inside the outer shell of the magnetic circuit coil. The coil body is connected to the coil frame and is located on one side of the coil frame.

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