Electron beam device

Abstract

The invention provides an electron beam device. Wherein the electron beam device comprises: a filament connected as a cathode to a negative high voltage and configured to generate an electron beam; the extraction electrode is in positive high voltage relative to the lamp filament and is configured to extract electrons from the emitting surface of the lamp filament to form electron beams; and the focusing lens is configured to adjust the size of the half field angle of the electron beam so as to generate light spots with different sizes and different beam densities on the surface of the to-be-detected sample, so that charges, generated by the imaging equipment, of different conditions on the surface of the to-be-detected sample are eliminated. The electron beam device can eliminate charges of different conditions on the surface of the sample to be detected, improves the imaging quality of imaging equipment, guarantees the accuracy of image information, is suitable for various different charge conditions, and effectively enlarges the application range. Charge of a specific area on the surface of the to-be-detected sample can be eliminated, positions sensitive to electron beams and light are prevented from being damaged, and the performance of the to-be-detected sample is guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor detection technology, in particular to an electron beam device. Background Art

[0002] Electron beam imaging equipment generally includes scanning electron microscopes, electron beam defect detection equipment, electron beam critical dimension measurement equipment, etc., and X-ray imaging equipment generally includes X-ray spectrometers, etc. During the imaging process of electron beam imaging equipment and X-ray imaging equipment, the sample surface usually produces a charging effect due to charge accumulation, especially for samples with poor surface conductivity, the charging effect is often more serious. This will affect the imaging quality and image information of the imaging equipment, where the imaging quality mainly includes image resolution, contrast, signal strength, etc. For example, during the imaging process of a scanning electron microscope, surface charging may cause problems such as overexposure or too dark images. Therefore, eliminating the influence of charging effects on imaging is crucial for the normal use of these imaging equipment and obtaining accurate image information.

[0003] Currently, various methods and specialized devices have been proposed to address the issue of eliminating the impact of charging effects on imaging. The most widely used approach uses optical or high-current electron beams to illuminate the sample area to be imaged, neutralizing the charge in that area or achieving a relatively stable saturation state. However, a major drawback of existing technologies is that the light or electron beam spot size is large, making it impossible to precisely control the area where charging effects need to be suppressed or adjusted. This can affect sample performance, such as damaging areas sensitive to the electron beam or light. Summary of the Invention

[0004] One purpose of the present invention is to eliminate the charge in different conditions on the surface of the sample to be detected and effectively expand the scope of application.

[0005] A further object of the present invention is to improve the adjustment accuracy of the electron beam so as to eliminate the charge in a specific area of the surface of the sample to be inspected.

[0006] In particular, the present invention provides an electron beam device, which is arranged on one side of an imaging device, and includes: a filament, which serves as a cathode and is connected to a negative high voltage, and is configured to generate an electron beam; an extraction electrode, which is a positive high voltage relative to the filament, and is configured to extract electrons from the emission surface of the filament to form an electron beam; and a focusing lens, which is configured to adjust the size of the half-angle of the electron beam to generate light spots of different sizes and different beam densities on the surface of the sample to be detected, thereby eliminating the different conditions of charging generated on the surface of the sample to be detected by the imaging device.

[0007] Optionally, the electron beam device also includes: an adjustment electrode, arranged between the extraction electrode and the focusing lens, configured to perform preliminary adjustment on the convergence degree of the electron beam; an aperture, arranged on the side of the focusing lens away from the adjustment electrode, configured to limit, select or adjust the shape and size of the electron beam; and a deflector, arranged on the side of the aperture away from the focusing lens, configured to control the deflection and scanning direction of the electron beam.

[0008] Optionally, the electron beam device also includes: a main cavity, the interior of which is a vacuum environment, and an electron beam outlet is opened on one side of the main cavity, configured to emit an electron beam; the main cavity is also provided with a vacuum feeding interface, configured to be connected to an external power supply cable, and the vacuum feeding interface is located on any side of the main cavity without an electron beam outlet.

[0009] Optionally, the filament, the extraction electrode, the adjustment electrode, the focusing lens, the aperture, and the deflector are sequentially arranged inside the main cavity in a direction gradually approaching the electron beam outlet.

[0010] Optionally, the electron beam device also includes: a beam gate, arranged between the focusing lens and the aperture, configured to apply an electric field or a magnetic field to the electron beam to cause the electron beam to deviate from the main optical axis, wherein the main optical axis is a straight line from the beam source center of the electron beam to the center of the scanning range of the surface of the sample to be detected; a receiver, configured to receive the electron beam that deviates from the main optical axis; and a current measuring device, connected to the receiver, configured to measure the beam current size of the electron beam.

[0011] Optionally, the electron beam detection device is configured with a focusing scanning working mode, and in the focusing scanning working mode, the adjustment electrode and the focusing lens are configured to converge the electron beam onto the surface of the sample to be detected, and the electron beam is controlled by the deflector to scan the surface of the sample to be detected, so as to utilize the light spot generated by the electron beam to eliminate the charge in a specific area of the surface of the sample to be detected.

[0012] Optionally, the electron beam detection device is also configured with a divergent working mode, and in the divergent working mode, the adjustment electrode and the focusing lens are configured to increase the divergence angle of the electron beam, and make part of the beam current of the electron beam blocked by the aperture, so as to utilize the light spot generated by the electron beam to eliminate the charge on the surface of the sample to be detected, the size of the light spot in the divergent working mode is larger than the size of the light spot in the focused scanning working mode, and the beam current density of the light spot in the divergent working mode is smaller than the beam current density of the light spot in the focused scanning working mode.

[0013] Optionally, the electron beam detection device is also configured with a convergence-divergence working mode, and in the convergence-divergence working mode, the adjustment electrode and the focusing lens are configured to converge the electron beam and then diverge it to produce a convergence point close to the aperture, so as to utilize the light spot generated by the electron beam to eliminate the charge on the surface of the sample to be detected, the size of the light spot in the convergence-divergence working mode is larger than the size of the light spot in the focusing-scanning working mode, and the beam current density of the light spot in the convergence-divergence working mode is smaller than the beam current density of the light spot in the focusing-scanning working mode but greater than the beam current density of the light spot in the divergence working mode.

[0014] Optionally, the electron beam device is further configured to suppress emission of the electron beam from the filament by applying a negative pressure relative to the filament to the extraction electrode or the adjustment electrode.

[0015] Optionally, the material of the filament is tungsten or lanthanum hexaboride; the extraction electrode and the adjustment electrode are both axially symmetrical electrode plates with a central circular hole; the focusing lens is an axially symmetrical electric lens or magnetic lens, wherein the electric lens is composed of a group of electrode plates with concentric circular holes in the center, and the magnetic lens is composed of a group of coils, or a group of coils plus a coaxial iron core or a magnetic metal pole shoe; the deflector is composed of an even number of polar-symmetrical electrode plates or coils, and the deflector is provided with one or more groups; the aperture is a thin sheet with a central hole; the beam gate is a pair of electrode plates or a deflection coil group; the receiver is a cup-shaped or bowl-shaped conductive structure, the bottom of which is connected to the current measuring device by a cable.

[0016] The electron beam device of the present invention is arranged on one side of the imaging device, and the electron beam device includes: a filament, which is connected to a negative high voltage as a cathode and is configured to generate an electron beam; an extraction electrode, which is a positive high voltage relative to the filament and is configured to extract electrons from the emission surface of the filament to form an electron beam; and a focusing lens, which is configured to adjust the size of the half-angle of the electron beam to generate light spots of different sizes and different beam current densities on the surface of the sample to be detected, thereby eliminating the different conditions of charging generated by the imaging device on the surface of the sample to be detected, improving the imaging quality of the imaging device, ensuring the accuracy of image information, and being applicable to a variety of different charging conditions, effectively expanding the scope of application.

[0017] Furthermore, in the focusing scanning working mode, the electron beam device of the present invention adjusts the electrodes and the focusing lens to be configured to converge the electron beam onto the surface of the sample to be detected, and controls the electron beam to scan the surface of the sample to be detected through the deflector, so as to utilize the light spot generated by the electron beam to eliminate the charge in a specific area on the surface of the sample to be detected. By improving the adjustment accuracy of the electron beam, the charge in the specific area on the surface of the sample to be detected can be eliminated, thereby avoiding damage to positions sensitive to the electron beam and light, and ensuring the performance of the sample to be detected.

[0018] Based on the following detailed description of specific embodiments of the present invention in conjunction with the accompanying drawings, those skilled in the art will become more aware of the above and other objects, advantages and features of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Hereinafter, some specific embodiments of the present invention will be described in detail in an exemplary and non-limiting manner with reference to the accompanying drawings. The same reference numerals in the accompanying drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the accompanying drawings:

[0020] Figure 1 is a schematic structural diagram of an electron beam device according to one embodiment of the present invention;

[0021] Figure 2 is a schematic structural diagram of an electron beam device according to another embodiment of the present invention;

[0022] Figure 3 is a schematic diagram of a focusing and scanning operating mode of an electron beam device according to one embodiment of the present invention;

[0023] Figure 4 yes Figure 3 Scanning schematic diagram of the focus scanning working mode;

[0024] Figure 5 is a schematic diagram of a divergent operating mode of an electron beam device according to one embodiment of the present invention; and

[0025] Figure 6 FIG. 1 is a schematic diagram of a convergence-divergence working mode of an electron beam device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0026] This embodiment provides an electron beam device that can eliminate charges in different conditions on the surface of a sample to be detected, effectively expanding the scope of application. Figure 1 Schematic diagram of the structure of an electron beam device according to an embodiment of the present invention. The electron beam device of this embodiment is arranged on one side of the imaging device. Specifically, the electron beam device can be arranged on the side of the lens barrel of the imaging device at an angle. Figure 1 As shown, the electron beam device of this embodiment may generally include: a filament 101 , a suction electrode 102 and a focusing lens 104 . Figure 2 FIG. 1 is a schematic structural diagram of an electron beam device according to another embodiment of the present invention. Figure 2 As shown, the electron beam device may further include: a beam gate 107 , a receiver 108 and a current measuring device.

[0027] The filament 101 serves as a cathode and is connected to a negative high voltage, configured to generate an electron beam 400. In a specific embodiment, the material of the filament 101 is tungsten or lanthanum hexaboride. Tungsten or lanthanum hexaboride has a high melting point and high temperature resistance, good electron emission performance, high physical and chemical stability, and good processing properties. Using tungsten or lanthanum hexaboride as the material for the filament 101 can effectively improve the electron emission capability, stability, and service life.

[0028] The extraction electrode 102 is at a positive high voltage relative to the filament 101 and is configured to extract electrons from the emission surface of the filament 101 to form an electron beam 400. In other words, the filament 101 of this embodiment has an emission surface, which enables the electron beam emission source to be a planar source. Compared to a point source, this allows for a larger emission area and a relatively larger initial divergence angle of the electron beam 400. Furthermore, the total emission current is higher, and the adjustment methods for the electron beam 400 are more diverse, allowing the electron beam device to achieve a variety of different operating modes.

[0029] The focusing lens 104 is configured to adjust the half-angle of the electron beam 400 to produce light spots of varying sizes and beam current densities on the surface of the sample 300 to be inspected, thereby eliminating the varying charging conditions on the surface of the sample 300 to be inspected caused by the imaging device. In a preferred embodiment, the focusing lens 104 is an axially symmetric electric lens or magnetic lens. The electric lens can be composed of a set of electrode plates with concentric circular holes at their centers. The magnetic lens can be composed of a set of coils, or a set of coils plus a coaxial iron core or a magnetic metal pole piece.

[0030] Specifically, when electrons are emitted from a source, they don't propagate in a straight line due to various physical factors. Instead, they diverge within a certain angle range, forming a cone-like shape. The half angle of this cone is the electron beam half angle. The electron beam half angle can be understood as half of the maximum angle at which the electron beam 400 deviates from its principal optical axis. In a specific embodiment, the half angle of the electron beam 400 can be adjusted by adjusting the voltage or current of the focusing lens 104.

[0031] During the imaging process of an imaging device, the surface of the sample 300 to be inspected typically experiences a charging effect due to charge accumulation, which can affect the imaging quality and image information of the imaging device. The electron beam device of this embodiment can adjust the half-angle of the electron beam 400 to produce light spots of varying sizes and beam current densities on the surface of the sample 300 to be inspected. This eliminates the varying charging conditions on the surface of the sample 300 caused by the imaging device, improving the imaging quality of the imaging device and ensuring accurate image information. The device is also adaptable to a variety of charging conditions, effectively expanding its scope of application.

[0032] In a preferred embodiment, Figure 1As shown, the electron beam device may further include an adjustment electrode 103, an aperture 106, and a deflector 105. The adjustment electrode 103 is disposed between the extraction electrode 102 and the focusing lens 104 and is configured to perform preliminary adjustments to the convergence of the electron beam 400. In a specific embodiment, both the extraction electrode 102 and the adjustment electrode 103 are axisymmetric electrode plates with a central circular hole.

[0033] The aperture 106 is disposed on the side of the focusing lens 104 away from the adjustment electrode 103 and is configured to limit, select, or adjust the shape and size of the electron beam 400. In a specific embodiment, the aperture 106 is a thin sheet with a central hole. It should be noted that the central circular hole of the electrode plate and the central hole of the aperture 106 mentioned herein are both located on the principal optical axis, and an axisymmetric electrode plate also refers to an axisymmetric electrode plate with respect to the principal optical axis. The principal optical axis specifically refers to a straight line from the beam source center of the electron beam 400 to the center of the scanning range of the surface of the sample 300 to be detected.

[0034] The deflector 105 is disposed on the side of the aperture 106 away from the focusing lens 104 and is configured to control the deflection and scanning direction of the electron beam 400. In a specific embodiment, the deflector 105 is composed of an even number of polarly symmetrical electrode plates or coils. More specifically, the even number can be a multiple of 4. For example, a set of deflectors 105 can be composed of symmetrical electrode plates or coils with 4, 8, 12, or 16 poles. Furthermore, one or more sets of deflectors 105 can be provided.

[0035] like Figure 1 As shown, the electron beam device may further include: a main cavity 202. The interior of the main cavity 202 is a vacuum environment, and an electron beam outlet 203 is provided on one side of the main cavity 202, configured to emit an electron beam 400. In addition, the main cavity 202 is further provided with a vacuum feed-in interface 201, configured to be connected to an external power supply cable, and the vacuum feed-in interface 201 is located on any side of the main cavity 202 without the electron beam outlet 203. In a specific embodiment, as Figure 1 As shown, the vacuum feed-in interface 201 and the electron beam outlet 203 are located on two opposite sides of the main cavity 202 .

[0036] The filament 101, the extraction electrode 102, the adjustment electrode 103, the focusing lens 104, the aperture 106, and the deflector 105 are all encapsulated in the main cavity 202 in a vacuum environment. Figure 1 As shown, the filament 101 , the extraction electrode 102 , the adjustment electrode 103 , the focusing lens 104 , the aperture 106 , and the deflector 105 are sequentially arranged inside the main cavity 202 in a direction gradually approaching the electron beam outlet 203 .

[0037] In a specific embodiment, the electron beam device is further configured to suppress the emission of the electron beam 400 from the filament 101 by applying a negative pressure relative to the filament 101 to the extraction electrode 102 or the adjustment electrode 103. Because the filament 101 is not suitable for repeated on and off switching, especially for hot filaments 101 or hot field filaments 101, the emission of the electron beam 400 from the filament 101 can be temporarily shut off by applying a negative pressure relative to the filament 101 to the extraction electrode 102 or the adjustment electrode 103.

[0038] The beam gate 107 is disposed between the focusing lens 104 and the aperture 106 and is configured to apply an electric or magnetic field to the electron beam 400, causing the electron beam 400 to deviate from the main optical axis. The receiver 108 is configured to receive the electron beam 400 that has deviated from the main optical axis. A current measuring device is connected to the receiver 108 and is configured to measure the beam current of the electron beam 400.

[0039] Generally, when it is necessary to stop the electron beam 400 from scanning, an electric field or a magnetic field can be applied to the electron beam 400 through the beam gate 107 . Figure 2 The receiver 108 shown is located above the aperture 106 and faces the beam gate 107 to receive electron beam 400 that deviates from the main optical axis. This ensures complete reception, thereby ensuring accurate beam current measurement of electron beam 400 by a subsequent current measurement device. In a preferred embodiment, the beam gate 107 is a pair of electrode plates or a deflection coil assembly. The receiver 108 is a conductive cup- or bowl-shaped structure, the bottom of which is connected to a current measurement device via a cable. The current measurement device can be an ammeter.

[0040] In a specific embodiment, filament 101 acts as a cathode and is connected to a negative high voltage. Extraction electrode 102 is connected to a positive high voltage relative to filament 101, thereby extracting electrons from the emission surface of filament 101. Electron beam 400 can be initially converged by adjusting electrode 103, and its half-angle can be adjusted significantly by focusing lens 104. Aperture 106 can be used to block stray electrons or control the final emitted beam current.

[0041] By adjusting the voltage or current of the regulating electrode 103 and the focusing lens 104, the electron beam device can achieve three different operating modes: focused scanning mode, diverging mode, and convergent-diverging mode. In these three operating modes, the spot size and beam current density produced on the surface of the sample 300 to be inspected vary, and the charge conditions eliminated also differ.

[0042] Figure 3 FIG. 1 is a schematic diagram of a focusing scanning operation mode of an electron beam device according to an embodiment of the present invention. Figure 3As shown, the electron beam detection device is configured with a focusing scanning working mode, and in the focusing scanning working mode, the adjustment electrode 103 and the focusing lens 104 are configured to converge the electron beam 400 onto the surface of the sample to be detected 300, and the electron beam 400 is controlled by the deflector 105 to scan the surface of the sample to be detected 300, so as to utilize the light spot generated by the electron beam 400 to eliminate the charge in a specific area of the surface 300 of the sample to be detected.

[0043] Figure 4 yes Figure 3 Schematic diagram of the scanning in the focused scanning mode. It should be noted that the spot size of the focused scanning mode is very small and the beam density is very high. The deflector 105 can be used to control the electron beam 400 to scan a specific area on the surface of the sample 300 to be tested, thereby using the spot generated by the electron beam 400 to eliminate the charge in the specific area on the surface of the sample 300 to be tested. By scanning a specific area, it is possible to bypass areas that are not suitable for irradiation, such as areas with fine line structures of the sample, areas that may be damaged, or areas of special materials.

[0044] Figure 5 FIG. 1 is a schematic diagram of a divergent working mode of an electron beam device according to an embodiment of the present invention. Figure 5 As shown, the electron beam detection device is also configured with a diverging operating mode. In the diverging operating mode, the adjustment electrode 103 and the focusing lens 104 are configured to increase the divergence angle of the electron beam 400 and cause a portion of the beam current of the electron beam 400 to be blocked by the aperture 106, thereby utilizing the light spot generated by the electron beam 400 to eliminate the charge on the surface of the sample 300 to be detected. In addition, the size of the light spot in the diverging operating mode is larger than that in the focused scanning operating mode, and the beam current density of the light spot in the diverging operating mode is smaller than that in the focused scanning operating mode.

[0045] It should be noted that a very small current or voltage can be applied to the adjustment electrode 103 and the focusing lens 104, or even not applied at all, thereby effectively reducing the converging capability of the electron beam 400 and increasing the divergence angle of the electron beam 400. Therefore, the size of the light spot in the diverging operating mode is larger than that in the focused scanning operating mode. Furthermore, due to the larger coverage area, the deflector 105 generally does not need to operate in the diverging operating mode. Furthermore, because part of the electron beam 400 is blocked by the aperture 106, the beam current density of the light spot in the diverging operating mode is smaller than that in the focused scanning operating mode.

[0046] Figure 6 FIG. 1 is a schematic diagram of a convergent-divergent working mode of an electron beam device according to an embodiment of the present invention. Figure 6As shown, the electron beam detection device is also configured with a convergence-divergence working mode, and in the convergence-divergence working mode, the adjustment electrode 103 and the focusing lens 104 are configured to converge the electron beam 400 and then diverge it to generate a convergence point close to the aperture 106, so as to utilize the light spot generated by the electron beam 400 to eliminate the charge of the surface 300 of the sample to be detected, the size of the light spot in the convergence-divergence working mode is larger than the size of the light spot in the focusing-scanning working mode, and the beam current density of the light spot in the convergence-divergence working mode is smaller than the beam current density of the light spot in the focusing-scanning working mode but larger than the beam current density of the light spot in the divergence working mode.

[0047] It should be noted that a very large current or voltage can be applied to the adjustment electrode 103 and the focusing lens 104 to converge the electron beam 400. After converging, the electron beam 400 naturally diverges, and the divergence angle of the electron beam 400 is also very large. Therefore, the spot size in the convergence-divergence operating mode is larger than the spot size in the focus-scanning operating mode. In addition, due to the larger coverage area, the deflector 105 generally does not need to operate in the convergence-divergence operating mode.

[0048] The electron beam 400 converges to produce a convergence point near the aperture 106, and the convergence point can be located on the side of the aperture 106 near the electron beam outlet 203. Therefore, the electron beam 400 is basically not blocked by the aperture 106, and the beam current density of the light spot in the convergent-divergent working mode is greater than the beam current density of the light spot in the divergent working mode. However, because the electron beam 400 in the convergent-divergent working mode converges and then diverges, and the electron beam 400 in the focused-scanning working mode converges to the surface of the sample to be tested 300, the beam current density of the light spot in the convergent-divergent working mode is less than the beam current density of the light spot in the focused-scanning working mode. In addition, the electron beam device can eliminate slight charges in the divergent working mode and can eliminate severe charges in the focused-scanning working mode and the convergent-divergent working mode.

[0049] The electron beam device of this embodiment has spatial precision, intensity precision, and temporal precision. The electron beam device's operating mode can be selectively configured to address different charging conditions on the surface of the sample 300 to be inspected, such as the degree of charge, the size of the area requiring charge removal, and whether specific areas require charge removal. This allows the electron beam 400 to generate spots of varying sizes and beam current densities on the surface of the sample 300 to eliminate different charging conditions.

[0050] In summary, the electron beam device of this embodiment is arranged on one side of the imaging device, and the electron beam device includes: a filament 101, which is connected to a negative high voltage as a cathode and is configured to generate an electron beam 400; an extraction electrode 102, which is a positive high voltage relative to the filament 101 and is configured to extract electrons from the emission surface of the filament 101 to form an electron beam 400; and a focusing lens 104, which is configured to adjust the size of the half angle of the electron beam 400 to generate light spots of different sizes and different beam densities on the surface of the sample 300 to be detected, thereby eliminating the different conditions of charging generated by the imaging device on the surface of the sample 300 to be detected, improving the imaging quality of the imaging device, ensuring the accuracy of image information, and being applicable to a variety of different charging conditions, effectively expanding the scope of application.

[0051] Furthermore, in the focusing scanning working mode, the electron beam device of this embodiment adjusts the electrode 103 and the focusing lens 104 to be configured to converge the electron beam 400 onto the surface of the sample to be detected 300, and controls the electron beam 400 to scan the surface of the sample to be detected 300 through the deflector 105, so as to utilize the light spot generated by the electron beam 400 to eliminate the charge in the specific area of the surface of the sample to be detected 300. By improving the adjustment accuracy of the electron beam 400, the charge in the specific area of the surface of the sample to be detected 300 can be eliminated, thereby avoiding damage to the positions sensitive to the electron beam 400 and light, and ensuring the performance of the sample to be detected 300.

[0052] Those skilled in the art should understand that, unless otherwise specified, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", "clockwise", "counterclockwise", etc. in the embodiments of the present invention used to indicate orientation or positional relationships are merely for the convenience of describing and understanding the technical solutions of the present invention, and do not indicate or imply that the device or component referred to must have a specific orientation, and therefore should not be understood as limiting the present invention.

[0053] The terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the definition of "first", "second", etc. can explicitly or implicitly include at least one of the features, that is, include one or more of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. When a feature "includes or contains" one or more of the features it covers, unless otherwise specifically described, this indicates that other features are not excluded and may further include other features.

[0054] Unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," and the like should be interpreted broadly. For example, they may refer to fixed or detachable connections, or integration; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components, unless otherwise expressly limited. A person of ordinary skill in the art should be able to understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0055] In addition, in the description of this embodiment, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact via another feature between them. That is, in the description of this embodiment, the first feature being "above," "above," and "above" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature being "below," "below," or "below" the second feature may mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0056] In the description of the present embodiment, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "example," "specific example," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any appropriate manner in any one or more embodiments or examples.

[0057] At this point, those skilled in the art will recognize that, although a number of exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications consistent with the principles of the present invention may be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and deemed to cover all such other variations or modifications.

Claims

1. An electron beam device, arranged on one side of an imaging device, characterized in that: include: a filament connected as a cathode to a negative high voltage and configured to generate an electron beam; an extraction electrode, which is at a positive high voltage relative to the filament and is configured to extract electrons from the emission surface of the filament to form the electron beam; as well as The focusing lens is configured to adjust the size of the half angle of the electron beam to generate light spots of different sizes and different beam densities on the surface of the sample to be detected, thereby eliminating the different conditions of charging generated by the imaging device on the surface of the sample to be detected.

2. The electron beam device according to claim 1, wherein Also includes: an adjusting electrode, disposed between the suction electrode and the focusing lens, and configured to perform preliminary adjustment on the convergence degree of the electron beam; an aperture, disposed on a side of the focusing lens away from the adjustment electrode, configured to limit, select or adjust the shape and size of the electron beam; and The deflector is arranged on a side of the aperture away from the focusing lens and is configured to control the deflection and scanning direction of the electron beam.

3. The electron beam device according to claim 2, wherein Also includes: The main cavity has a vacuum environment inside, and An electron beam outlet is provided on one side of the main cavity, configured to emit the electron beam; The main cavity is further provided with a vacuum feed-in interface, which is configured to be connected to an external power supply cable. The vacuum feed-in interface is located on any side of the main cavity without the electron beam outlet.

4. The electron beam device according to claim 3, wherein The filament, the extraction electrode, the adjustment electrode, the focusing lens, the aperture, and the deflector are sequentially arranged inside the main cavity along a direction gradually approaching the electron beam outlet.

5. The electron beam device according to claim 4, wherein Also includes: a beam gate, disposed between the focusing lens and the aperture, configured to apply an electric field or a magnetic field to the electron beam to cause the electron beam to deviate from a main optical axis, wherein the main optical axis is a straight line from a beam source center of the electron beam to a center of a scanning range of the surface of the sample to be detected; a receiver configured to receive the electron beam deviated from the main optical axis; as well as The current measuring device is connected to the receiver and is configured to measure the beam current of the electron beam.

6. The electron beam detection device according to claim 2, characterized in that A focus scanning working mode is configured, and in the focus scanning working mode, The adjustment electrode and the focusing lens are configured to converge the electron beam onto the surface of the sample to be detected, and control the electron beam to scan the surface of the sample to be detected through the deflector, so as to utilize the light spot generated by the electron beam to eliminate the charge in a specific area of the surface of the sample to be detected.

7. The electron beam detection device according to claim 6, characterized in that It is also configured with a divergent working mode, and in the divergent working mode, The adjustment electrode and the focusing lens are configured to increase the divergence angle of the electron beam and enable part of the beam current of the electron beam to be blocked by the aperture, so as to utilize the light spot generated by the electron beam to eliminate the charge on the surface of the sample to be detected, the size of the light spot in the divergent working mode is larger than the size of the light spot in the focused scanning working mode, and the beam current density of the light spot in the divergent working mode is smaller than the beam current density of the light spot in the focused scanning working mode.

8. The electron beam detection device according to claim 7, characterized in that It is also configured with a convergent-divergent working mode, and in the convergent-divergent working mode, The adjustment electrode and the focusing lens are configured to converge the electron beam and then diverge it to produce a convergence point close to the aperture, so as to utilize the light spot generated by the electron beam to eliminate the charge on the surface of the sample to be detected. The size of the light spot in the convergence-divergence working mode is larger than the size of the light spot in the focus-scanning working mode, and the beam current density of the light spot in the convergence-divergence working mode is smaller than the beam current density of the light spot in the focus-scanning working mode but larger than the beam current density of the light spot in the divergence working mode.

9. The electron beam device according to claim 2, wherein Also configured as: By applying a negative pressure relative to the filament to the extraction electrode or the adjustment electrode, emission of the electron beam from the filament is suppressed.

10. The electron beam device according to claim 5, wherein The material of the filament is tungsten or lanthanum hexaboride; The suction electrode and the regulating electrode are both axisymmetric electrode plates with a central circular hole; The focusing lens is an axisymmetric electric lens or magnetic lens, wherein the electric lens is composed of a group of electrode plates with concentric circular holes in the center, and the magnetic lens is composed of a group of coils, or a group of coils plus a coaxial iron core or a magnetic metal pole shoe; The deflector is composed of an even number of polar-symmetrical electrode plates or coils, and the deflector is provided in one or more groups; The aperture is a thin sheet with a central hole; The beam gate is a pair of electrode plates or a deflection coil group; The receiver is a conductive structure in a cup or bowl shape, and the bottom of the receiver is connected to the current measuring device via a cable.

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