Electron beam control apparatus and method

Abstract

The application discloses an electron beam control device and method. The electron beam control device comprises a first generating assembly and a second generating assembly. The first generating assembly is used for generating a first magnetic field with a first intensity and / or a first direction to adjust a deflection angle and / or displacement of an electron beam emitted by an emission assembly of a scanning electron microscope passing through the first generating assembly, so that an optical axis of the electron beam coincides with a magnetic axis of a first focusing assembly of the scanning electron microscope. The second generating assembly is used for generating a second magnetic field with a second intensity and / or a second direction to adjust a deflection angle and / or displacement of the electron beam from the first generating assembly passing through the second generating assembly, so that the optical axis of the electron beam coincides with a magnetic axis of a second focusing assembly of the scanning electron microscope.

Description

Technical Field

[0001] This application relates to the field of electron microscopy, and more particularly to an electron beam control device and method. Background Technology

[0002] A scanning electron microscope is an electronic imaging device widely used in fields such as biology, semiconductors, and materials science. It can detect the microstructure and composition of objects.

[0003] However, during the process of obtaining an image of an object using a scanning electron microscope, aberrations may occur (which can be understood as the deviation between the actual image and the predicted image), thus affecting the image quality of the object. Summary of the Invention

[0004] To address the related technical problems, embodiments of this application provide an electron beam control device and method.

[0005] The technical solution of this application embodiment is implemented as follows:

[0006] This application provides an electron beam control device for use in a scanning electron microscope, comprising: a first generating component and a second generating component; wherein...

[0007] The first generating component is used to generate a first magnetic field of first intensity and / or first direction to adjust the deflection angle and / or displacement of the electron beam emitted by the emitting component of the scanning electron microscope passing through the first generating component, such that the optical axis of the electron beam coincides with the magnetic axis of the first focusing component of the scanning electron microscope.

[0008] The second generating component is used to generate a second magnetic field of a second strength and / or a second direction to adjust the deflection angle and / or displacement of the electron beam from the first generating component passing through the second generating component, such that the optical axis of the electron beam coincides with the magnetic axis of the second focusing component of the scanning electron microscope.

[0009] In the above-described apparatus, the first generation component includes: a first generation sub-component and a second generation sub-component; wherein,

[0010] The first generating sub-component is used to generate a third magnetic field of third strength and / or third direction to adjust the deflection angle of the electron beam emitted by the emitting component passing through the first generating sub-component;

[0011] The second generating sub-component is used to generate a fourth magnetic field of a fourth strength and / or a fourth direction to adjust the displacement of the electron beam from the first generating sub-component passing through the second generating sub-component.

[0012] In the above-described apparatus, the second generation sub-component includes: a third generation sub-component and a fourth generation sub-component; wherein,

[0013] The third generating sub-component is used to generate a fifth magnetic field of a fifth strength and / or a fifth direction to adjust the deflection angle of an electron beam from the first generating sub-component passing through the third generating sub-component.

[0014] The fourth generating sub-component is used to generate a sixth magnetic field of a sixth strength and / or a sixth direction to adjust the deflection angle of the electron beam from the third generating sub-component passing through the fourth generating sub-component; wherein the fifth magnetic field has the same strength as the sixth magnetic field and opposite directions.

[0015] In the above-described device, the first focusing component has a hollow structure, and the first generating sub-component is disposed within the hollow structure of the first focusing component.

[0016] In the aforementioned apparatus, the second generation component includes: a fifth generation sub-component and a sixth generation sub-component; wherein,

[0017] The fifth generating sub-component is used to generate a seventh magnetic field of a seventh strength and / or a seventh direction to adjust the displacement of the electron beam from the first generating component passing through the fifth generating sub-component;

[0018] The sixth generating sub-component is used to generate an eighth magnetic field of eighth strength and / or eighth direction to adjust the deflection angle of the electron beam from the fifth generating sub-component passing through the sixth generating sub-component.

[0019] In the above-described apparatus, the fifth generation sub-component includes: a seventh generation sub-component and an eighth generation sub-component; wherein,

[0020] The seventh generating sub-component is used to generate a ninth magnetic field of a ninth strength and / or a ninth direction to adjust the deflection angle of the electron beam from the first generating component passing through the seventh generating sub-component.

[0021] The eighth generating sub-component is used to generate a tenth magnetic field of tenth strength and / or tenth direction to adjust the deflection angle of the electron beam from the seventh generating sub-component passing through the eighth generating sub-component; wherein the ninth magnetic field has the same strength as the tenth magnetic field and opposite direction.

[0022] In the above-described device, the second focusing component has a hollow structure, and the sixth generating sub-component is disposed within the hollow structure of the second focusing component.

[0023] This application also provides an electron beam control method for use in a scanning electron microscope, including:

[0024] A first magnetic field of first intensity and / or first direction is generated to adjust the deflection angle and / or displacement of an electron beam emitted by the emission assembly of the scanning electron microscope through the first generating assembly of the scanning electron microscope, such that the optical axis of the electron beam coincides with the magnetic axis of the first focusing assembly of the scanning electron microscope.

[0025] A second magnetic field of second strength and / or second direction is generated to adjust the deflection angle and / or displacement of the electron beam from the first generating component passing through the second generating component of the scanning electron microscope, such that the optical axis of the electron beam coincides with the magnetic axis of the second focusing component of the scanning electron microscope.

[0026] In the above scheme, generating a first magnetic field of first intensity and / or first direction to adjust the deflection angle and / or displacement of the electron beam emitted by the emission component of the scanning electron microscope passing through the first generating component of the scanning electron microscope includes:

[0027] A third magnetic field of third strength and / or third direction is generated to adjust the deflection angle of the electron beam emitted by the emission assembly passing through the first generation sub-assembly in the first generation assembly;

[0028] A fourth magnetic field of fourth strength and / or fourth direction is generated to adjust the displacement of the electron beam from the first generating sub-component passing through the second generating sub-component in the first generating component.

[0029] In the above scheme, generating a second magnetic field of second intensity and / or second direction to adjust the deflection angle and / or displacement of the electron beam from the first generating component passing through the second generating component of the scanning electron microscope includes:

[0030] A seventh magnetic field of seventh strength and / or seventh direction is generated to adjust the displacement of the electron beam from the first generating component passing through the fifth generating sub-component in the second generating component;

[0031] An eighth magnetic field of eighth strength and / or eighth direction is generated to adjust the deflection angle of the electron beam from the fifth generating sub-component passing through the sixth generating sub-component in the second generating component.

[0032] The electron beam control device and method provided in this application embodiment involve a first generating component generating a first magnetic field of first intensity and / or first direction to adjust the deflection angle and / or displacement of an electron beam emitted by the emitting component of a scanning electron microscope passing through the first generating component, such that the optical axis of the electron beam coincides with the magnetic axis of the first focusing component of the scanning electron microscope; and a second generating component generating a second magnetic field of second intensity and / or second direction to adjust the deflection angle and / or displacement of an electron beam from the first generating component passing through the second generating component, such that the optical axis of the electron beam coincides with the magnetic axis of the second focusing component of the scanning electron microscope. The solution provided in this application embodiment generates magnetic fields of specific magnitude and / or direction by the first and second generating components to adjust the displacement and / or deflection angle of the electron beam as it passes through these components, thereby achieving coincidence of the optical axis and magnetic axis. This avoids aberrations caused by tilting or deflection of the electron beam, ensuring the imaging quality of the object. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of the first electron beam control device according to the embodiments of this application;

[0034] Figure 2 This is a schematic diagram of the structure of the second type of electron beam control device according to an embodiment of this application;

[0035] Figure 3 This is a schematic diagram of the structure of the first generation component in an embodiment of this application;

[0036] Figure 4 This is a schematic diagram of the structure of the third magnetic field in an embodiment of this application;

[0037] Figure 5 This is a schematic diagram of the structure of the third type of electron beam control device according to an embodiment of this application;

[0038] Figure 6 This is a schematic diagram of the structure of the fourth type of electron beam control device according to an embodiment of this application;

[0039] Figure 7 This is a schematic diagram of the structure of the fifth electron beam control device according to an embodiment of this application;

[0040] Figure 8 This is a schematic diagram of the centering device for a scanning electron microscope, which is an application example of this application.

[0041] Figure 9 This is a schematic diagram of the method flow for centering a scanning electron microscope, which is an application example of this application;

[0042] Figure 10 This is a schematic diagram of the structure of the first type of component misalignment in the application example of this application;

[0043] Figure 11 This is a schematic diagram of the structure of the first type of adjustment component pair in the application example of this application;

[0044] Figure 12 This is a schematic diagram of the structure of the second type of misaligned component in the application example of this application;

[0045] Figure 13 This is a schematic diagram of the structure of the second type of adjustment component pair in the application example of this application;

[0046] Figure 14 This is a schematic diagram of the structure of the third type of misaligned component in the application example of this application;

[0047] Figure 15 This is a schematic diagram of the structure of the third type of adjustment component pair in the application example of this application;

[0048] Figure 16 This is a schematic diagram of the fourth type of misaligned component in the application example of this application;

[0049] Figure 17 This is a schematic diagram of the structure of a deflection coil assembly, which is an application example of this application.

[0050] Figure 18 This is a schematic diagram of the structure of the fourth type of adjustment component pair in the application example of this application;

[0051] Figure 19 This is a schematic flowchart of the electron beam control method according to an embodiment of this application. Detailed Implementation

[0052] The present application will now be described in further detail with reference to the accompanying drawings and embodiments.

[0053] The main principle of scanning electron microscopy is as follows: an electron beam is emitted from the cathode of an electron gun. Under the action of accelerating electrodes, the electron beam is focused by two electromagnetic lenses (with focusing function) into an electron beam probe (which can be understood as a very fine electron beam) that reaches the surface of the object under test. Driven by scanning deflection electrodes in the objective lens, the electron beam probe can perform array scanning (i.e., scanning in temporal or spatial order) on the surface of the object under test. Because the electron beam probe has high energy, it can excite various physical signals such as secondary electrons and backscattered electrons when incident on the surface of the object under test. These physical signals are acquired by corresponding detectors, amplified and transmitted by signal amplifiers, and then imaged on a display screen on the server side, thus obtaining information on the microstructure and composition of the object under test.

[0054] During the production and use of scanning electron microscopes, the electron beam passes through multiple apertures and electromagnetic lenses to reach the surface of the object under test. Due to limitations in the manufacturing and / or assembly precision of components in the objective lens and electron gun, errors may exist in the positions of the electron gun cathode, anode, electromagnetic lenses, and apertures. This causes the electron beam to tilt or deviate as it passes these components, resulting in an optical alignment deviation (which can be understood as the optical axis of the electron beam not coinciding with the optical or magnetic axes of the aforementioned components). This produces aberrations such as astigmatism, distortion, or spherical aberration, affecting the image quality of the object under test. To obtain high-quality images, the scanning electron microscope needs to be aligned to reduce aberrations caused by alignment deviations, thereby ensuring image quality.

[0055] Based on this, in various embodiments of this application, an electron beam control device is proposed, which is deployed on a scanning electron microscope. The electron beam control device generates a magnetic field of a specific size and / or direction to adjust the displacement and / or deflection angle of the electron beam as it passes through the device, thereby achieving alignment of the optical axis and the magnetic axis. This avoids aberrations caused by tilting or deflection of the electron beam, ensuring the imaging quality of the object.

[0056] This application provides an electron beam control device for use in a scanning electron microscope, such as... Figure 1 As shown, the device includes: a first generation component 101 and a second generation component 102; wherein,

[0057] The first generating component 101 is used to generate a first magnetic field of first intensity and / or first direction to adjust the deflection angle and / or displacement of the electron beam emitted by the emitting component of the scanning electron microscope passing through the first generating component 101, so that the optical axis of the electron beam coincides with the magnetic axis of the first focusing component of the scanning electron microscope.

[0058] The second generating component 102 is used to generate a second magnetic field of a second strength and / or a second direction to adjust the deflection angle and / or displacement of the electron beam from the first generating component passing through the second generating component 102, such that the optical axis of the electron beam coincides with the magnetic axis of the second focusing component of the scanning electron microscope.

[0059] In practical applications, the scanning electron microscope can be divided into two parts: a gun lens and an objective lens. The gun lens includes at least an emitting component and a first focusing component. The emitting component, which can be called an electron gun, may specifically include a cathode and an anode. The emitting component emits an electron beam, which can be understood as an electron stream obtained by accelerating and focusing a large number of electrons. For example, the cathode of the emitting component emits the electron beam. Furthermore, the first focusing component, which can be called a first focusing lens gun lens, has at least a focusing function, capable of focusing the electron beam passing through it. The first focusing component can generate a gun lens magnetic field to focus the electron beam passing through it. This application does not limit the names of the emitting component and the first focusing component, as long as their functions are implemented.

[0060] In practical applications, the objective lens includes at least an aperture assembly and a second focusing assembly. The aperture assembly, which can be called a movable objective aperture, is used to adjust the intensity of the electron beam passing through it. Furthermore, the second focusing assembly, which can be called a second focusing lens objective, at least has a focusing function, capable of focusing the electron beam passing through it. This application does not limit the names of the aperture assembly and the second focusing assembly, as long as their functions are implemented.

[0061] Here, because the installation positions of the various components in the gun lens may be deviated during the installation of the scanning electron microscope, causing the electron beam to tilt or shift when passing through the gun lens, resulting in off-axis aberration, the first generating component 101 can be placed in the gun lens to generate a magnetic field of a specific size and / or direction, thereby adjusting the displacement and / or deflection angle of the electron beam when passing through the components in the gun lens; wherein, the first generating component 101 may specifically include two sub-components, so as to adjust the displacement and deflection angle of the electron beam when passing through the components in the gun lens respectively through the two sub-components.

[0062] Specifically, in one embodiment, such as Figure 2 As shown, the first generation component 101 includes: a first generation sub-component 1011 and a second generation sub-component 1012; wherein,

[0063] The first generating sub-component 1011 is used to generate a third magnetic field of third intensity and / or third direction to adjust the deflection angle of the electron beam emitted by the emitting component passing through the first generating sub-component 1011;

[0064] The second generating sub-component 1012 is used to generate a fourth magnetic field of a fourth strength and / or a fourth direction to adjust the displacement of the electron beam from the first generating sub-component 1011 passing through the second generating sub-component 1012.

[0065] Here, during the installation of the gun scope, the emitting component may not be installed horizontally, causing the emitted electron beam to tilt when it enters the objective lens after being focused by the first focusing component. This results in off-axis aberration between the optical axis and the magnetic axis of the first focusing component. As a result, a large number of electrons may not be able to reach the surface of the object under test, thus affecting the image quality.

[0066] To solve the above problems, the first generating sub-component 1011 can be placed in the magnetic field generated by the first focusing component, so as to adjust the deflection angle of the electron beam when passing through the first generating sub-component 1011, so that the optical axis coincides with the magnetic axis of the first focusing component.

[0067] Based on this, in one embodiment, the first focusing component has a hollow structure, and the first generating sub-component 1011 is disposed within the hollow structure of the first focusing component.

[0068] In practical applications, the first focusing component has a hollow structure, such as a circular hollow structure. After the input current is applied, a magnetic field can be generated inside the hollow structure. Therefore, the first generating sub-component 1011 can be placed inside the hollow structure of the first focusing component, that is, the first generating sub-component 1011 can be placed in the magnetic field of the first focusing component to adjust the deflection angle of the electron beam passing through the first generating component 1011.

[0069] In practical applications, to determine whether the emitting component is horizontally mounted, a current can be input to the first focusing component to observe the brightness of the object image. If the brightness of the object image does not change, it is determined that the emitting component is horizontally mounted; if the brightness of the object image changes, it is determined that the emitting component is not horizontally mounted. This is because: after inputting current to the first focusing component, the first focusing component generates a magnetic field. If the emitting component is not horizontally mounted, the emitted electron beam will tilt towards the magnetic axis as it passes through the first focusing component, causing the number of electrons reaching the surface of the object to be measured to be different from the number of electrons reaching the surface of the object to be measured when the first focusing component is not input with current. This results in a difference in the brightness of the object image compared to the brightness of the object image when the first focusing component is not input with current.

[0070] If it is determined that the emitting component is not horizontally mounted, a first current can be input to the first generating sub-component 1011 to generate the third magnetic field of the third intensity and / or third direction, thereby changing the deflection angle of the electron beam and achieving the coincidence of the optical axis with the magnetic axis of the first focusing component; wherein, the third intensity is related to the magnitude of the first current, and the third direction is related to the direction of the first current.

[0071] For example, if it is determined that the emitting component is not horizontally installed, the electron beam will tilt towards the magnetic axis when passing through the first focusing component, causing a large number of electrons to fail to reach the surface of the object under test, affecting the brightness of the object image. Therefore, the current of the first generating sub-component 1011 is adjusted until the brightness of the object image reaches its maximum when the first current is input. At this time, it is indicated that the optical axis of the electron beam coincides with the magnetic axis of the first focusing component, and all electrons can reach the surface of the object under test.

[0072] It should be noted that the working principle of the first generation sub-component 1011 is as follows: the first generation sub-component 1011 may contain four deflection coils, such as... Figure 3 As shown, these are represented as +Y, -Y, -X, and +X, respectively. For each deflection coil, the deflection coil generates a corresponding sub-magnetic field after the input current; the magnitude of the sub-magnetic field is directly proportional to the ampere-turns (related to the current magnitude), and the directions of the generated sub-magnetic fields are perpendicular to each other. By superimposing multiple sub-magnetic fields, a third magnetic field with a third direction and a third intensity can be obtained. Thus, when the electron beam passes through the third magnetic field at a certain speed, according to the Lorentz force law, the moving charge in the magnetic field will be subjected to the Lorentz force, and under the action of the Lorentz force, the direction of motion of the electron beam can be deflected; the magnitude of the Lorentz force F can be expressed as: F = qV × B, where q represents the charge of the electron beam, V represents the velocity of the electron beam, and B represents the magnitude of the magnetic field (i.e., the first intensity).

[0073] In the above process, when the electron beam passes through the third magnetic field, such as Figure 4 As shown, the third magnetic field can be decomposed into a sub-magnetic field along the X-axis (denoted as B). X ) and the sub-magnetic field along the Y-axis (denoted as B) Y Correspondingly, the current can also be decomposed into sub-currents along the X-axis (denoted as I). X ) and the sub-current along the Y-axis (denoted as I) Y This allows us to explain the relationship between the electron beam's deflection direction and distance and I. X and I Y Therefore, by changing the current input to the first generating sub-component 1011 (specifically including I...) X and IY This allows the generation of a third magnetic field of the third intensity and / or third direction, which changes the deflection angle of the electron beam, thereby achieving the alignment of the optical axis with the magnetic axis of the first focusing component.

[0074] In practical applications, during the installation of the scanning electron microscope, the emitting component may not be aligned and installed at the center of the first focusing component. That is, there is a displacement (specifically, a horizontal displacement) between the optical axis of the electron beam and the magnetic axis of the first focusing component. This may cause a large number of electrons to be blocked when they are focused by the first focusing component and enter the objective lens, thus failing to reach the surface of the object under test and affecting the imaging quality.

[0075] Here, to determine whether the emitting component is not centered on the first focusing component, the current of the first focusing component and / or the second focusing component can be adjusted so that the object image is in overfocus, focused, and underfocus states, respectively. In this case, if the object image center moves, it is determined that the emitting component is not centered on the first focusing component; if the object image center does not move, it is determined that the emitting component is centered on the first focusing component. This is because: as the current of the first focusing component and / or the second focusing component changes, the magnetic field strength generated by the first focusing component and / or the second focusing component changes along the magnetic axis. If the emitting component is not centered on the first focusing component, the magnetic field strength will affect the direction of electron beam movement, causing the electron beam to oscillate with the change in magnetic field strength, resulting in a shift in the object image center.

[0076] In practical applications, if it is determined whether the transmitting component is not aligned and installed at the center of the first focusing component, the displacement of the electron beam from the first generating component 1011 passing through the second generating sub-component 1012 can be adjusted by the second generating sub-component 1012, so that the optical axis of the electron beam coincides with the magnetic axis of the first focusing component.

[0077] In practical applications, the function of the second generation sub-component 1012 can be achieved through two sub-components.

[0078] Specifically, in one embodiment, such as Figure 5 As shown, the second generation sub-component 1012 includes: a third generation sub-component 10121 and a fourth generation sub-component 10122; wherein,

[0079] The third generating sub-component 10121 is used to generate a fifth magnetic field of a fifth strength and / or a fifth direction to adjust the deflection angle of the electron beam from the first generating sub-component 1011 passing through the third generating sub-component 10121.

[0080] The fourth generating sub-component 10122 is used to generate a sixth magnetic field of a sixth strength and / or a sixth direction to adjust the deflection angle of the electron beam from the third generating sub-component 10121 passing through the fourth generating sub-component 10122; wherein the fifth magnetic field has the same strength as the sixth magnetic field and opposite directions.

[0081] In practical applications, the third generation sub-component 10121 may specifically include four deflection coils, and the fourth generation sub-component 10122 may specifically include four deflection coils. The working principle of the third generation sub-component 10121 and the fourth generation sub-component 10122 may be the same as that of the first generation sub-component 1011. This application embodiment does not limit this.

[0082] In practical applications, if it is determined that the transmitting component is not aligned with the center of the first focusing component, a second current can be input to the third generating sub-component 10121 to generate the fifth magnetic field of the fifth intensity and / or fifth direction. Simultaneously, a third current can be input to the fourth generating sub-component 10122 to generate the sixth magnetic field of the sixth intensity and / or sixth direction. The second and third currents are of the same magnitude but opposite in direction. Since the intensity and / or direction of the magnetic field are related to the magnitude and / or direction of the current, by inputting currents of the same magnitude but opposite direction to the third and fourth generating sub-components 10121 and 10122, it is possible to generate magnetic fields of the same intensity but opposite direction.

[0083] For example, by adjusting the current of the first focusing component and / or the second focusing component so that the object imaging is in the over-focus, focused and under-focus states respectively, the current of the third generation sub-component 10121 and the fourth generation sub-component 10122 are adjusted respectively until the object imaging center no longer moves. At this time, it can be determined that a second current is input to the third generation sub-component 10121 and a third current is input to the fourth generation sub-component 10122.

[0084] In practical applications, when it is determined that the emitting component is not horizontally installed and is not centered on the first focusing component, the third magnetic field of the third intensity and / or third direction generated by the first generating sub-component 1011 can adjust the deflection angle of the electron beam as it passes through the first generating sub-component 1011. The fifth magnetic field of the fifth intensity and / or fifth direction and the sixth magnetic field of the sixth intensity and / or sixth direction generated by the third generating sub-component 10121 and the fourth generating sub-component 10122 respectively can adjust the displacement of the electron beam as it passes through the third generating sub-component 10121 and the fourth generating sub-component 10122. However, during the process of adjusting the current of the third generating sub-component 10121 and the fourth generating sub-component 10122 to adjust the displacement of the electron beam, the electron beam may tilt again, causing a deflection angle between the optical axis of the electron beam and the magnetic axis of the first focusing component. Therefore, while adjusting the displacement of the electron beam, it is also necessary to consider whether the electron beam tilts.

[0085] For example, by adjusting the current of the first focusing component and / or the second focusing component so that the object imaging is in the over-focus, focused and under-focus states respectively, the current of the third generation sub-component 10121 and the fourth generation sub-component 10122 are adjusted respectively until the object imaging center no longer moves and the brightness of the object imaging is at its maximum. At this time, it can be determined that a second current is input to the third generation sub-component 10121 and a third current is input to the fourth generation sub-component 10122.

[0086] Thus, after the electron beam passes through the first generating sub-component 1011 and reaches the third generating sub-component 10121, it is deflected by the fifth magnetic field of the fifth strength and / or fifth direction during its passage through the third generating sub-component 10121. The direction of motion changes from vertically downward to tilted towards the magnetic axis of the first focusing component, allowing the electron beam to generate horizontal displacement until it passes through the third generating sub-component 10121 and reaches the fourth generating sub-component 10122. During its passage through the fourth generating sub-component 10122, the electron beam is affected by the sixth magnetic field of the sixth strength and / or sixth direction, and is deflected again by the Lorentz force. Since the sixth magnetic field and the fifth magnetic field have the same strength but opposite magnitudes, the direction of motion of the electron beam can change from tilted towards the magnetic axis of the first focusing component to vertically downward. This achieves displacement adjustment of the electron beam, making the optical axis of the electron beam coincide with the magnetic axis of the first focusing component.

[0087] In practical applications, during the installation of the scanning electron microscope, the gun lens may deviate from the installation position of the objective lens, causing the electron beam to tilt or shift when passing through the objective lens from the gun lens, resulting in off-axis aberration. Therefore, the position of the aperture assembly in the objective lens can be adjusted so that the center of the aperture assembly, the optical axis of the electron beam, and the magnetic axis of the first focusing assembly can coincide.

[0088] For example, a linearly varying current (e.g., from -10A to 10A) is input to the third generation sub-component 10121 and the fourth generation sub-component 10122, causing the strengths of the fifth and sixth magnetic fields to change with the current. This results in the electron beam oscillating, enabling scanning of the aperture assembly. Simultaneously, by adjusting the current of the first focusing component, the electron beam is focused onto the aperture assembly to obtain an image of the aperture assembly. The position of the aperture assembly along the X-axis and Y-axis is adjusted by the motor of the aperture assembly, moving it to the center of the image. In this way, the center of the aperture assembly, the optical axis of the electron beam, and the magnetic axis of the first focusing component can be aligned.

[0089] In practical applications, during the installation of the scanning electron microscope, the installation positions of the various components in the objective lens may be deviated, causing the electron beam to tilt or shift when passing through the objective lens, resulting in off-axis aberration. Therefore, the second generating component 102 can be placed in the objective lens to generate a magnetic field of a specific size and / or direction, thereby adjusting the displacement and / or deflection angle of the electron beam when passing through the components in the objective lens. Specifically, the second generating component 102 may include two sub-components, which can be used to adjust the displacement and deflection angle of the electron beam when passing through the components in the objective lens, respectively.

[0090] Specifically, in one embodiment, such as Figure 6 As shown, the second generation component 102 includes: a fifth generation sub-component 1021 and a sixth generation sub-component 1022; wherein,

[0091] The fifth generating sub-component 1021 is used to generate a seventh magnetic field of a seventh strength and / or a seventh direction to adjust the displacement of the electron beam from the first generating component 101 passing through the fifth generating sub-component 1021.

[0092] The sixth generating sub-component 1022 is used to generate an eighth magnetic field of eighth strength and / or eighth direction to adjust the deflection angle of the electron beam from the fifth generating sub-component 1021 passing through the sixth generating sub-component 1022.

[0093] In practical applications, during the installation of the objective lens, the second focusing component may not be aligned and installed at the center of the aperture assembly. This causes a displacement between the optical axis of the electron beam and the magnetic axis of the second focusing component when the electron beam passes through the aperture assembly and reaches the second focusing component, resulting in off-axis aberration. As a result, a large number of electrons may not be able to reach the surface of the object under test, thus affecting the image quality.

[0094] To determine whether the second focusing component is centered on the aperture assembly, the current of the second focusing component can be adjusted to put the object image in overfocus, focused, and underfocus states, respectively. In this case, if the object image center shifts, it is determined that the second focusing component is not centered on the aperture assembly; if the object image center does not shift, it is determined that the second focusing component is centered on the aperture assembly. This is because: as the current of the second focusing component changes, the magnetic field strength generated by the second focusing component changes along the magnetic axis. If the second focusing component is not centered on the aperture assembly, the magnetic field strength will affect the direction of electron beam movement, causing the electron beam to oscillate with the change in magnetic field strength, resulting in a shift in the object image center.

[0095] In practical applications, if it is determined that the second focusing component is not aligned and installed at the center of the aperture component, the displacement of the electron beam from the first generating sub-component 1011 passing through the second generating sub-component 1021 can be adjusted by the fifth generating sub-component 1021, so that the optical axis of the electron beam coincides with the magnetic axis of the second focusing component.

[0096] In practical applications, the function of the fifth generation sub-component 1021 can be achieved through two sub-components.

[0097] Specifically, in one embodiment, such as Figure 7 As shown, the fifth generation sub-component 1021 includes: a seventh generation sub-component 10211 and an eighth generation sub-component 10212; wherein,

[0098] The seventh generating sub-component 10211 is used to generate a ninth magnetic field of a ninth strength and / or a ninth direction to adjust the deflection angle of the electron beam from the first generating component 101 passing through the seventh generating sub-component 10211.

[0099] The eighth generating sub-component 10212 is used to generate a tenth magnetic field of tenth strength and / or tenth direction to adjust the deflection angle of the electron beam from the seventh generating sub-component 10211 passing through the eighth generating sub-component 10212; wherein the ninth magnetic field has the same strength as the tenth magnetic field and opposite direction.

[0100] In practical applications, the seventh generation sub-component 10211 may specifically include four deflection coils, and the eighth generation sub-component 10212 may specifically include four deflection coils. The working principle of the seventh generation sub-component 10211 and the eighth generation sub-component 10212 may be the same as that of the first generation sub-component 1011. This application embodiment does not limit this.

[0101] In practical applications, if it is determined that the second focusing component is not centered on the aperture component, a fourth current can be input to the seventh generating sub-component 10211 to generate a ninth magnetic field of ninth strength and / or ninth direction. Simultaneously, a fifth current can be input to the eighth generating sub-component 10212 to generate a tenth magnetic field of tenth strength and / or tenth direction. The fourth current and the fifth current have the same magnitude but opposite directions. Since the strength and / or direction of the magnetic field are related to the magnitude and / or direction of the current, by inputting currents of the same magnitude but opposite directions to the seventh and eighth generating sub-components 10211 and 10212, it is possible to generate magnetic fields of the same strength but opposite directions.

[0102] For example, by adjusting the current of the first focusing component and / or the second focusing component so that the object imaging is in the over-focus, focused and under-focus states respectively, the current of the seventh generation sub-component 10211 and the eighth generation sub-component 10212 are adjusted respectively until the object imaging center no longer moves. At this time, it can be determined that a fourth current is input to the seventh generation sub-component 10211 and a fifth current is input to the eighth generation sub-component 10212.

[0103] Thus, after the electron beam passes through the aperture assembly and reaches the seventh generating sub-assembly 10211, it is affected by the ninth magnetic field of the ninth strength and / or the ninth direction during its passage through the seventh generating sub-assembly 10211. Under the action of the Lorentz force, the electron beam deflects, and its direction of motion changes from vertically downward to tilting towards the magnetic axis of the second focusing assembly. At this time, the electron beam can generate horizontal displacement until it passes through the seventh generating sub-assembly 10211 and reaches the eighth generating sub-assembly 10212. During its passage through the eighth generating sub-assembly 10212, the electron beam is affected by the tenth magnetic field of the tenth strength and / or the tenth direction. Under the action of the Lorentz force, it deflects again. Since the ninth and tenth magnetic fields have the same strength but opposite magnitudes, the direction of motion of the electron beam can change from tilting towards the magnetic axis of the second focusing assembly to vertically downward. In this way, the displacement adjustment of the electron beam is achieved, so that the optical axis of the electron beam coincides with the magnetic axis of the second focusing assembly.

[0104] Here, during the installation of the objective lens, the second focusing component may not be installed horizontally, causing the electron beam to tilt when it enters the second focusing component after passing through the aperture assembly. This results in off-axis aberration between the optical axis of the electron beam and the magnetic axis of the second focusing component. As a result, a large number of electrons may not be able to reach the surface of the object under test, thus affecting the image quality.

[0105] To solve the above problems, the sixth generating sub-component 1022 can be placed in the magnetic field generated by the second focusing component to adjust the deflection angle of the electron beam from the fifth generating sub-component 1021 passing through the sixth generating sub-component 1022.

[0106] Based on this, in one embodiment, the second focusing component has a hollow structure, and the sixth generating sub-component 1022 is disposed within the hollow structure of the second focusing component.

[0107] In practical applications, the second focusing component has a hollow structure, such as a circular hollow structure. After the input current, a magnetic field can be generated in the hollow structure. Therefore, the sixth generating sub-component 1022 can be set in the hollow structure of the second focusing component, that is, the sixth generating sub-component 1022 is set in the magnetic field of the second focusing component to adjust the deflection angle of the electron beam passing through the sixth generating sub-component 1022.

[0108] In practical applications, to determine whether the second focusing component is horizontally mounted, the current of the second focusing component can be adjusted to make the object image appear in overfocus, focused, and underfocus states, respectively. In this case, if the focusing degree of the object image edges is consistent, it is determined that the second focusing component is horizontally mounted; if the focusing degree of the object image edges is inconsistent, it is determined that the second focusing component is not horizontally mounted. This is because: if the second focusing component is not horizontally mounted, when the electron beam is focused onto the surface of the object under test through the second focusing lens, the focal length of the electron beam scanning one edge of the object surface is different from the focal length scanning the other edge, resulting in inconsistent focusing degree at the object image edges. For example, if the left edge of the object image is in focus, the right edge of the object image may be overfocused or underfocused.

[0109] If it is determined that the second focusing component is not horizontally mounted, a fifth current can be input to the sixth generating sub-component 1022 to generate an eighth magnetic field of the eighth intensity and / or the eighth direction, thereby changing the deflection angle of the electron beam and achieving the coincidence of the optical axis with the magnetic axis of the second focusing component; wherein, the eighth intensity is related to the magnitude of the fifth current, and the eighth direction is related to the direction of the fifth current.

[0110] For example, when it is determined that the second focusing component is not horizontally mounted, the current of the second focusing component is adjusted so that the object image is in the overfocus, focused and underfocus states respectively. During this process, the current of the sixth generating sub-component 1022 is adjusted until the focusing degree of the object image edge is consistent. At this time, it can be determined that a fifth current is input to the sixth generating sub-component 1022.

[0111] In practical applications, when it is determined that the second focusing component is not horizontally installed and is not centered on the aperture component, the seventh generating sub-component 10211 and the eighth generating sub-component 10212 generate a ninth magnetic field of ninth intensity and / or ninth direction and a tenth magnetic field of tenth intensity and / or tenth direction, respectively, which can adjust the displacement of the electron beam passing through the seventh generating sub-component 10211 and the eighth generating sub-component 10212; the sixth generating sub-component 1022 generates the eighth magnetic field of eighth intensity and / or eighth direction, which can adjust the deflection angle of the electron beam passing through the sixth generating sub-component 1022. However, in the process of adjusting the current of the sixth generating sub-component 1022 to adjust the deflection angle of the electron beam, the electron beam may be translated, resulting in displacement between the optical axis of the electron beam and the magnetic axis of the first focusing component. Therefore, while adjusting the deflection angle of the electron beam, it is also necessary to consider whether the electron beam will be translated.

[0112] For example, while adjusting the current of the second focusing component so that the object image is in the overfocus, focused and underfocus states respectively, the current of the sixth generating sub-component 1022 is adjusted until the focusing degree of the object image edge is consistent and the object image center no longer moves. At this time, it can be determined that the fifth current is input to the sixth generating sub-component 1022.

[0113] In this way, when the electron beam passes through the sixth generator component 1022, it is affected by the eighth magnetic field of the eighth strength and / or the eighth direction. The electron beam will be deflected under the action of the Lorentz force, so that the electron beam can move along the direction of the magnetic axis of the second focusing component, thus realizing the coincidence of the optical axis of the electron beam with the magnetic axis of the second focusing component.

[0114] The electron beam control device provided in this application embodiment includes a first generating component 101 that generates a first magnetic field of first intensity and / or first direction to adjust the deflection angle and / or displacement of the electron beam emitted by the emitting component of the scanning electron microscope passing through the first generating component 101, so that the optical axis of the electron beam coincides with the magnetic axis of the first focusing component of the scanning electron microscope; and a second generating component 102 that generates a second magnetic field of second intensity and / or second direction to adjust the deflection angle and / or displacement of the electron beam from the first generating component 101 passing through the second generating component 102, so that the optical axis of the electron beam coincides with the magnetic axis of the second focusing component of the scanning electron microscope. The solution provided in this application embodiment generates magnetic fields of specific size and / or direction by the first and second generating components to adjust the displacement and / or deflection angle of the electron beam as it passes through the aforementioned components, thereby achieving the coincidence of the optical axis and magnetic axis. This avoids aberrations caused by tilting or deflection of the electron beam, ensuring the imaging quality of the object.

[0115] The following section provides a more detailed description of this application with reference to application examples.

[0116] In the application examples of this application, such as Figure 8 As shown, a scanning electron microscope centering device is proposed, specifically comprising a deflection coil group 1 (i.e., the first generating sub-component mentioned above), a deflection coil group 2 (i.e., the third generating sub-component mentioned above), a deflection coil group 3 (i.e., the fourth generating sub-component mentioned above), a first focusing lens (i.e., the first focusing component mentioned above), a second focusing lens objective (i.e., the second focusing component mentioned above), and a movable objective aperture (i.e., the aperture component mentioned above), a deflection coil group 4 (i.e., the seventh generating sub-component mentioned above), a deflection coil group 5 (i.e., the eighth generating sub-component mentioned above), and a deflection coil group 6 (i.e., the sixth generating sub-component mentioned above); each deflection coil group contains 4 deflection coils.

[0117] Here, the principle of deflecting the electron beam by the deflection coil group is as follows: When current is input to the four deflection coils, the resulting magnetic field is proportional to the ampere-turns. In other words, changing the magnitude of the current controls the magnitude of the magnetic field, and changing the direction of the current controls the direction of the magnetic field. The directions of the magnetic fields are mutually perpendicular, which can be understood as the X-axis and Y-axis directions in a coordinate system. By superimposing the magnetic fields in these two directions, a magnetic field of arbitrary magnitude and direction can be achieved within a certain range (limited by the range of output current values ​​driven by the current source).

[0118] In practical applications, the process of centering a scanning electron microscope using a centering device is as follows: Figure 9 As shown, it includes the following steps:

[0119] Step 901: Acquire the image of the movable aperture of the objective lens;

[0120] In practical applications, firstly, after an electron beam is emitted through the electron gun cathode, a linearly changing current (e.g., a triangular waveform current) is provided to deflection coil groups 2 and 3. This generates a changing magnetic field in the deflection coil groups 2 and 3, causing the electron beam to oscillate and scan the movable aperture of the objective lens. Next, the current input to the first focusing lens is adjusted so that the electron beam can be focused onto the movable aperture of the objective lens. In this way, the scanning electron microscope can display the aperture image, and then step 902 is executed.

[0121] Step 902: Adjust the center of the movable aperture of the objective lens;

[0122] The movable objective aperture includes a motor in the X-axis direction and a motor in the Y-axis direction. The motor in the X-axis direction is used to adjust the displacement of the movable objective aperture along the X-axis direction, and the motor in the Y-axis direction is used to adjust the displacement of the movable objective aperture along the Y-axis direction.

[0123] Here, by adjusting the motors in the X-axis direction and the Y-axis direction, the movable aperture of the objective lens is moved to the center of the image, and then step 903 is executed.

[0124] Step 903: Obtain sample images;

[0125] In practical applications, the input current to the first focusing lens is stopped, as are the input currents to deflection coil groups 2 and 3. The in-objective deflection scanner is turned on (i.e., the input current is provided to deflection coil groups 4 and 5) to scan the sample and obtain an image. The current input to the second focusing lens is adjusted so that the electron beam can be focused onto the sample surface.

[0126] Step 904: Centering objective lens movable stop and second focusing lens objective;

[0127] Here, as Figure 10 As shown, if the second focusing lens objective is not aligned with the center of the movable aperture during installation, the optical axis of the electron beam passing through the center of the movable aperture will not be aligned with the magnetic axis corresponding to the second focusing lens objective, thus producing off-axis aberration and affecting the imaging quality.

[0128] To solve the above problem, deflection coil group 4 (specifically containing 4 deflection coils, denoted as 4+X, 4-X, 4+Y, 4-Y) and deflection coil group 5 (specifically containing 4 deflection coils, denoted as 5+X, 5-X, 5+Y, 5-Y) are supplied with currents of the same magnitude but opposite directions; where I is the input current for 4+X. X2 , is the 4-X input current I X2 , is the 4+Y input current I Y2 , is the 4-Y input current I Y2 ; is the input current of 5+X - I X2 , is the 5-X input current -I X2 , is the 5+Y input current -I Y2 , is the 5-Y input current -I Y2 In this case, such as Figure 11 As shown, when the electron beam passes through deflection coil group 4, it is affected by the magnetic field generated by deflection coil group 4, and its direction of motion changes from vertically downward to tilted towards the magnetic axis. When it passes through deflection coil group 5, it is affected by the magnetic field generated by deflection coil group 5, and the direction of motion of the electron beam changes again. Since the input current of deflection coil groups 4 and 5 is the same in magnitude and opposite in direction, they can generate magnetic fields of the same magnitude but opposite in direction, causing the direction of motion of the electron beam to change from tilted downward to its original vertical downward, thus achieving translation of the electron beam. In this way, the electron beam can pass through the center of the movable aperture of the objective lens and reach the sample surface along the magnetic axis of the second focusing lens objective lens, achieving alignment of the optical axis and the magnetic axis.

[0129] In the above process, to determine the current input to deflection coil groups 4 and 5, the current of the second focusing lens objective can be linearly adjusted (can be expressed as wobble) so that the sample image is in overfocus, focused, and underfocus states, respectively. For example, assuming the sample image is in focus when the current of the second focusing lens objective is 0.8A, in underfocus when the current is 0.75A, and in overfocus when the current is 0.85A, then providing a current of 0.75A to 0.85A to the second focusing lens objective will cause the sample image to cycle through overfocus, focused, and underfocus states. When the image center moves, by adjusting the current of deflection coil groups 4 and 5, the image center can be stabilized. At this point, the magnitude and direction of the current input to deflection coil groups 4 and 5 can be determined.

[0130] Next, proceed to step 905.

[0131] Step 905: Correct the tilt of the second focusing lens objective;

[0132] In practical applications, such as Figure 12 As shown, if the second focusing lens objective is not installed perpendicular to the optical axis, the magnetic axis of the second focusing lens objective will be tilted, resulting in off-axis aberration and affecting the imaging quality.

[0133] To solve the above problem, a specific magnitude and direction of current is supplied to the No. 6 deflection coil group (specifically comprising four deflection coils, denoted as 6+X, 6-X, 6+Y, and 6-Y). In this case, as... Figure 13 As shown, by providing a current of a specific magnitude and direction to the No. 6 deflection coil group, the direction of the generated magnetic field can be controlled, thereby controlling the direction of the electron beam's movement. This allows the electron beam to pass through the magnetic field center of the second focusing lens objective and reach the sample surface, thus achieving alignment of the optical axis and the magnetic axis.

[0134] In the above process, in order to determine the current input to the No. 6 deflection coil group, the current of the No. 6 deflection coil group can be adjusted until the center and edge of the sample image are in the same focus. At this time, the magnitude and direction of the current input to the No. 6 deflection coil group can be determined.

[0135] Step 906: Center the objective lens (also known as the lens tube);

[0136] In practical applications, it is determined whether adjusting the current of the second focusing lens objective satisfies the condition that the center of the sample image does not move and that the center and edge of the sample image are focused to the same degree. If this condition is met, step 907 is executed; otherwise, step 904 is executed.

[0137] It should be noted that in step 904, the movable aperture of the objective lens and the second focusing lens objective lens can be aligned. However, in step 905, that is, in the process of correcting the tilt of the second focusing lens objective lens, the optical axis and the magnetic axis may become misaligned. Therefore, when adjusting the current of the second focusing lens objective lens, it is necessary to ensure that the center of the sample image does not move and that the center of the sample image and the edge are in the same degree of focus. In this way, the alignment of each component in the objective lens can be achieved.

[0138] Step 907: Correct the electron beam tilt;

[0139] In practical applications, such as Figure 14 As shown, assuming the electron gun cathode is not placed horizontally during installation, the emitted electron beam will be deflected at an angle to the magnetic axis of the first focusing lens. When the electron beam is focused by the first focusing lens and incident on the movable aperture of the objective lens, it may hit the edge of the movable aperture or hit the side wall of the device after passing through the movable aperture. This will block a large number of electrons from reaching the sample surface, affecting the intensity of the electron beam on the sample surface and reducing the signal-to-noise ratio. At the same time, the electron beam will deviate from the magnetic axis of the second focusing lens, producing aberrations and affecting the imaging quality.

[0140] To solve the above problem, a current of specific magnitude and direction is supplied to deflection coil group 1 (specifically comprising 4 deflection coils, denoted as 1+X, 1-X, 1+Y, and 1-Y); deflection coil group 1 is located within the magnetic field of the first focusing lens. In this case, as... Figure 15 As shown, by providing a current of a specific magnitude and direction to the No. 1 deflection coil group, the direction of the generated magnetic field can be controlled, thereby controlling the direction of movement of the electron beam, so that the electron beam moves in the vertical direction, and thus passes through the magnetic axis of the first focusing lens objective and the center of the movable aperture of the objective lens to reach the sample surface, so as to achieve the alignment of the optical axis and the magnetic axis.

[0141] In practical applications, to determine the current input to the No. 1 deflection coil group, the current of the first focusing lens gun lens can be adjusted, and the current of the second focusing lens objective lens can be finely adjusted to bring the sample image into focus. At the same time, the current of the No. 1 deflection coil group can be adjusted to maximize the image brightness. At this point, the magnitude and direction of the current input to the No. 1 deflection coil group can be determined.

[0142] Step 908: Correct electron beam translation;

[0143] Here, it is assumed that the electron gun cathode was not aligned with the center of the first focusing lens gun mirror during installation, resulting in a horizontal displacement between the electron beam and the magnetic axis of the first focusing lens gun mirror. When the electron beam passes through the first focusing lens gun mirror and enters the movable aperture of the objective lens, it may hit the edge of the movable aperture, or after passing through the movable aperture, it may hit the side wall of the device, causing a large number of electrons to be blocked and unable to reach the sample surface. At the same time, the electron beam will deviate from the magnetic axis of the second focusing lens objective, producing aberrations and affecting the image quality.

[0144] To solve the above problems, such as Figure 17 As shown, deflection coil group 2 (specifically containing 4 deflection coils, denoted as 2+X, 2-X, 2+Y, 2-Y) and deflection coil group 3 (specifically containing 4 deflection coils, denoted as 3+X, 3-X, 3+Y, 3-Y) are provided with input currents of the same magnitude but opposite directions; where I is the input current I for 2+X. X1 , is the 2-X input current I X1 , is the 2+Y input current I Y1 , is the 2-Y input current I Y1 ; is the input current -I of 3+X X1 , is the 3-X input current -I X1 , is the 3+Y input current -I Y1 , is the 3-Y input current -I Y1 In this case, such as Figure 18 As shown, when the electron beam passes through deflection coil group 2, it is affected by the magnetic field generated by deflection coil group 2, and its direction of motion changes from vertically downward to tilted towards the magnetic axis. When it passes through deflection coil group 3, it is affected by the magnetic field generated by deflection coil group 3, and the direction of motion of the electron beam changes again. Since the input current of deflection coil groups 2 and 3 is the same in magnitude and opposite in direction, they can generate magnetic fields of the same magnitude but opposite in direction, causing the direction of motion of the electron beam to change from tilted downward to its original vertical downward, thus achieving translation of the electron beam. In this way, the electron beam can pass through the center of the movable aperture of the objective lens and through the magnetic field center of the second focusing lens objective lens to reach the sample surface, achieving alignment of the optical axis and the magnetic axis.

[0145] In practical applications, to determine the input current to deflection coil groups 2 and 3, the current of the second focusing lens objective can be linearly adjusted to bring the sample image into overfocus, focused, and underfocus states, respectively, and to determine whether the image center has shifted. If the image center has shifted, the current to deflection coil groups 4 and 5 can be adjusted to stop the image center from shifting. At this point, the magnitude and direction of the input current to deflection coil groups 4 and 5 can be determined.

[0146] Next, proceed to step 909.

[0147] Step 909: Center the scope;

[0148] In practical applications, when the sample image brightness is at its highest, it is determined whether the center of the sample image does not move when the current of the second focusing lens objective is adjusted; if it does, then proceed to step 910; otherwise, proceed to step 907.

[0149] It should be noted that while step 907 can correct the tilt of the electron beam, step 908, which is the process of correcting the translation of the electron beam, may cause the optical axis and magnetic axis to deviate from the axis. Therefore, when adjusting the current of the deflection coil group and the second focusing lens objective, it is necessary to ensure that the brightness of the sample image is at its highest and that the center of the sample image does not move. In this way, the alignment of the components in the gun scope can be achieved.

[0150] Step 910: Determine whether the aperture image is centered in the sample image;

[0151] Here, if the aperture image is in the center of the sample image, the current process ends; otherwise, step 902 is executed.

[0152] In practical applications, objective lens alignment can be achieved through steps 904 to 906; and gun lens alignment can be achieved through steps 907 to 909. However, during gun lens alignment, if it is determined that the electron beam is tilted and / or translated, it indicates that objective lens alignment is based on the tilted and / or translated electron beam. Therefore, after correcting the tilt and / or translation of the electron beam to achieve gun lens alignment, the gun lens may become off-axis with the objective lens, i.e., the gun lens and objective lens are not aligned. To determine whether the gun lens and objective lens are off-axis, the positional relationship between the aperture image and the sample image can be used. Specifically, by adjusting the movable aperture of the objective lens, the aperture image can be adjusted to the center of the sample image. When correcting the tilt and / or translation of the electron beam, the tilt angle and / or displacement of the electron beam will change, causing the position of the aperture image to change, so that the aperture image is no longer located at the center of the sample image. At this point, it can be determined that the gun lens and objective lens are off-axis, and step 902 is executed to re-align the scanning electron microscope.

[0153] Based on the electron beam control device of this application embodiment, this application embodiment also provides an electron beam control method, applied to a scanning electron microscope, such as... Figure 19 As shown, the method includes:

[0154] Step 1901: Generate a first magnetic field of first intensity and / or first direction to adjust the deflection angle and / or displacement of the electron beam emitted by the emission assembly of the scanning electron microscope through the first generating assembly of the scanning electron microscope, such that the optical axis of the electron beam coincides with the magnetic axis of the first focusing assembly of the scanning electron microscope.

[0155] Step 1902: Generate a second magnetic field of a second strength and / or a second direction to adjust the deflection angle and / or displacement of the electron beam from the first generating component passing through the second generating component of the scanning electron microscope, such that the optical axis of the electron beam coincides with the magnetic axis of the second focusing component of the scanning electron microscope.

[0156] In the above scheme, generating a first magnetic field of first intensity and / or first direction to adjust the deflection angle and / or displacement of the electron beam emitted by the emission component of the scanning electron microscope passing through the first generating component of the scanning electron microscope includes:

[0157] A third magnetic field of third strength and / or third direction is generated to adjust the deflection angle of the electron beam emitted by the emission assembly passing through the first generation sub-assembly in the first generation assembly;

[0158] A fourth magnetic field of fourth strength and / or fourth direction is generated to adjust the displacement of the electron beam from the first generating sub-component passing through the second generating sub-component in the first generating component.

[0159] In the above scheme, generating a second magnetic field of second intensity and / or second direction to adjust the deflection angle and / or displacement of the electron beam from the first generating component passing through the second generating component of the scanning electron microscope includes:

[0160] A seventh magnetic field of seventh strength and / or seventh direction is generated to adjust the displacement of the electron beam from the first generating component passing through the fifth generating sub-component in the second generating component;

[0161] An eighth magnetic field of eighth strength and / or eighth direction is generated to adjust the deflection angle of the electron beam from the fifth generating sub-component passing through the sixth generating sub-component in the second generating component.

[0162] It should be noted that terms such as "first" and "second" are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0163] Furthermore, the technical solutions described in the embodiments of this application can be combined arbitrarily without conflict.

[0164] The above description is merely a preferred embodiment of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. An electron beam control device, characterized in that, Applied to scanning electron microscopy, it includes: a first generation component and a second generation component; wherein, The first generating component is used to generate a first magnetic field of first intensity and / or first direction to adjust the deflection angle and / or displacement of the electron beam emitted by the emitting component of the scanning electron microscope passing through the first generating component, such that the optical axis of the electron beam coincides with the magnetic axis of the first focusing component in the gun lens of the scanning electron microscope. The first generating component is disposed in the gun lens, and the first focusing component has a hollow structure that can generate a gun lens magnetic field within the hollow structure to focus the electron beam passing through the first focusing component. The second generating component is used to generate a second magnetic field of a second intensity and / or a second direction to adjust the deflection angle and / or displacement of the electron beam from the first generating component passing through the second generating component, such that the optical axis of the electron beam coincides with the magnetic axis of the second focusing component in the objective lens of the scanning electron microscope. The second generating component is disposed in the objective lens, and the second focusing component has a hollow structure capable of generating a magnetic field within the hollow structure to focus the electron beam passing through the second focusing component. The first generation component includes: a first generation subcomponent and a second generation subcomponent; wherein, The first generating sub-component is configured to generate a third magnetic field of third strength and / or third direction when the emitting component is not horizontally mounted, so as to adjust the deflection angle of the electron beam emitted by the emitting component passing through the first generating sub-component; The second generating sub-component is configured to generate a fourth magnetic field of a fourth strength and / or a fourth direction when the emitting component is not mounted at the center of the first focusing component, in order to adjust the displacement of the electron beam from the first generating sub-component passing through the second generating sub-component; The second generation component includes: a fifth generation sub-component and a sixth generation sub-component; wherein, The fifth generating sub-component is used to generate a seventh magnetic field of seventh intensity and / or seventh direction when the second focusing component is not installed at the center of the aperture component in the objective lens, so as to adjust the displacement of the electron beam from the first generating component passing through the fifth generating sub-component; The sixth generating sub-component is used to generate an eighth magnetic field of eighth strength and / or eighth direction when the second focusing component is not horizontally mounted, in order to adjust the deflection angle of the electron beam from the fifth generating sub-component passing through the sixth generating sub-component.

2. The apparatus according to claim 1, characterized in that, The second generation sub-component includes: a third generation sub-component and a fourth generation sub-component; wherein, The third generating sub-component is used to generate a fifth magnetic field of a fifth strength and / or a fifth direction to adjust the deflection angle of an electron beam from the first generating sub-component passing through the third generating sub-component. The fourth generating sub-component is used to generate a sixth magnetic field of a sixth strength and / or a sixth direction to adjust the deflection angle of the electron beam from the third generating sub-component passing through the fourth generating sub-component; wherein the fifth magnetic field has the same strength as the sixth magnetic field and opposite directions.

3. The apparatus according to claim 1, characterized in that, The first generating sub-component is set within the hollow structure of the first focusing component.

4. The apparatus according to claim 1, characterized in that, The fifth generation sub-component includes: a seventh generation sub-component and an eighth generation sub-component; wherein, The seventh generating sub-component is used to generate a ninth magnetic field of a ninth strength and / or a ninth direction to adjust the deflection angle of the electron beam from the first generating component passing through the seventh generating sub-component. The eighth generating sub-component is used to generate a tenth magnetic field of tenth strength and / or tenth direction to adjust the deflection angle of the electron beam from the seventh generating sub-component passing through the eighth generating sub-component; wherein the ninth magnetic field has the same strength as the tenth magnetic field and opposite direction.

5. The apparatus according to claim 1, characterized in that, The sixth generating sub-component is disposed within the hollow structure of the second focusing component.

6. An electron beam control method, characterized in that, Applications in scanning electron microscopy include: A first magnetic field of first intensity and / or first direction is generated to adjust the deflection angle and / or displacement of the electron beam emitted by the emission component of the scanning electron microscope through the first generating component, such that the optical axis of the electron beam coincides with the magnetic axis of the first focusing component in the gun lens of the scanning electron microscope. The first generating component is disposed in the gun lens, and the first focusing component has a hollow structure that can generate a gun lens magnetic field within the hollow structure to focus the electron beam passing through the first focusing component. Generating a second magnetic field of second intensity and / or second direction to adjust the deflection angle and / or displacement of the electron beam emitted from the first generating component through the second generating component of the scanning electron microscope, such that the optical axis of the electron beam coincides with the magnetic axis of the second focusing component in the objective lens of the scanning electron microscope, the second generating component being disposed in the objective lens, the second focusing component having a hollow structure capable of generating a magnetic field within the hollow structure to focus the electron beam passing through the second focusing component; wherein, generating a first magnetic field of first intensity and / or first direction to adjust the deflection angle and / or displacement of the electron beam emitted by the emitting component of the scanning electron microscope through the first generating component of the scanning electron microscope includes: In the absence of the emitting component being horizontally mounted, a third magnetic field of third strength and / or third direction is generated to adjust the deflection angle of the electron beam emitted by the emitting component passing through the first generating sub-component in the first generating component; In the absence of the emission component being mounted at the center of the first focusing component, a fourth magnetic field of fourth strength and / or fourth direction is generated to adjust the displacement of the electron beam from the first generating sub-component passing through the second generating sub-component in the first generating component. The generation of a second magnetic field of second strength and / or second direction to adjust the deflection angle and / or displacement of the electron beam from the first generating component passing through the second generating component of the scanning electron microscope includes: When the second focusing component is not installed at the center of the aperture assembly in the objective lens, a seventh magnetic field of seventh intensity and / or seventh direction is generated to adjust the displacement of the electron beam from the first generating component passing through the fifth generating sub-component in the second generating component; When the second focusing component is not horizontally mounted, an eighth magnetic field of eighth strength and / or eighth direction is generated to adjust the deflection angle of the electron beam from the fifth generating sub-component passing through the sixth generating sub-component in the second generating component.

Images