Compact corrector module for charged particle microscope system and charged particle system

Abstract

To provide compact correctors for correcting spherical aberrations of a particle-optical lens in a charged particle microscope system.SOLUTION: A compact corrector 100 comprises a strong hexapole 102 configured to generate a strong hexapole field when a voltage is applied to it, and a weak hexapole 104 positioned between the strong hexapole and a sample. The strong hexapole is positioned such that the crossover of a charged particle beam 106 of the charged particle system does not pass through the center of the strong hexapole, such that the strong hexapole field applies at least an A2 aberration and a D4 aberration to the charged particle beam. The weak hexapole is further positioned or otherwise configured such that when a voltage is applied to the weak hexapole, it generates a weak hexapole field that applies at least a combination A2 aberration and a combination D4 aberration to the charged particle beam of the charged particle microscope system.SELECTED DRAWING: Figure 1

Description

[Background technology]

[0001] Particle-optical microscopes utilize round lenses to direct the electron / charged particle beam to illuminate the specimen. However, round lenses produce a positive spherical aberration coefficient (Cs) that limits higher aperture angles and inhibits resolution and probe current. Over the years, many Cs corrector systems have been developed to address spherical aberration in microscope systems such as transmission electron microscopes (TEMs) and scanning transmission electron microscopes (STEMs).

[0002] However, Cs correctors have been difficult to successfully implement in scanning electron microscope (SEM) columns because such correctors are difficult to manufacture and their manufacturing costs are very high. This is because current Cs corrector designs used in S(T)EM systems require many additional components that can be difficult to manufacture and therefore expensive. These many additional elements and excitations are typically required to nullify parasitic aberrations caused by mechanical errors inherent in normal component manufacturing techniques. For this reason, the cost of such techniques exceeds the budget of most SEM users. These factors have caused the cost of many current Cs correctors for SEM systems to exceed the cost of the SEM column itself, so it is desirable to find a simpler and more compact Cs corrector system (e.g., having fewer components that are easier to manufacture) that can correct for spherical aberrations in an SEM optical column. Furthermore, additional cost savings are realized if highly accurate manufacturing techniques such as MEMS technology are also used. Summary of the Invention

[0003] According to the present disclosure, a compact corrector for correcting spherical aberration of a particle-optical lens in a charged particle microscope system includes a first multipole element (e.g., a hexapole element, an octapole element, a dipole element, etc.) configured to generate a strong hexapole field when a first voltage is applied, and a second multipole element configured to generate a weak hexapole field positioned between the first multipole element and a sample when the corrector module is used in the charged particle microscope system. According to the present invention, the strong hexapole is positioned such that a crossover of a charged particle beam of the charged particle system does not pass through a center of the first multipole element (i.e., the strong hexapole), such that the first multipole element field applies at least A2 and D4 aberrations to the charged particle beam. The second multipole element is further positioned or otherwise configured such that when a second voltage is applied to the second multipole element, a weak hexapole field generated by the second multipole element applies at least a combined A2 aberration and a combined D4 aberration to a charged particle beam of the charged particle microscope system. In this manner, the net combination of aberrations applied to the charged particle beam by the weak hexapole field and the strong hexapole field results in a beam at or near the sample plane having the desired A2, C3, and D4 aberrations.

[0004] Additionally, a charged particle system including a compact corrector according to the present disclosure includes a sample holder configured to hold a sample, a charged particle source configured to emit a charged particle beam toward the sample, an optical column configured to direct the charged particle beam so that it is incident on the sample, and a detector system configured to detect emissions resulting from the sample being irradiated by the charged particle beam. The optical column includes a compact corrector module comprising a first multipole (i.e., a strong hexapole) configured to generate a strong hexapole field when a first voltage is applied thereto, and a second multipole (i.e., a weak hexapole) positioned between the strong hexapole and the sample. The strong hexapole is positioned such that a crossover of the charged particle beam does not pass through a center of the strong hexapole, causing the strong hexapole field to apply at least the combined A2 and D4 aberrations to the charged particle beam, and when a second voltage is applied to the weak hexapole, the weak hexapole generates a weak hexapole field that applies at least the combined A2 and combined D4 aberrations to the charged particle beam.

[0005] Further, an optical corrector module for a charged particle column with a split multipole according to the present invention includes at least one split multipole consisting of two multipoles (e.g., wafer multipole, magnetic multipole, electrostatic multipole, etc.) separated by a distance of less than any of 100 mm, 10 mm, 1 mm, 100 μm, and 10 μm. Each individual multipole comprises at least two electrodes positioned to partially define a beam path through the multipole. According to the present invention, each of the electrodes comprises a first surface facing the upstream of the charged particle beam when used in the charged particle column and a second surface facing the downstream of the charged particle beam when used in the charged particle column, and the thickness between the first surface and the second surface of each of the electrodes is less than 3 mm. Within the scope of the present disclosure, the split multipole may be electrostatic and may correspond to a hexapole. [Brief description of the drawings]

[0006] The detailed description will be set forth with reference to the accompanying drawings, in which the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same reference numbers in different figures indicate similar or identical items. [Figure 1] 1 illustrates an exemplary compact corrector for correcting A2, C3, and / or D4 aberrations at or near the specimen plane in accordance with the present invention. [Diagram 2] 1 illustrates an exemplary charged particle microscope system for inspection of components of a sample in accordance with the present invention, the optical column of which includes a miniature corrector for correcting A2, C3, and / or D4 aberrations at or near the sample plane. [Diagram 3] 13A-13C show alternative example embodiments of a compact corrector for correcting A2, C3, and / or D4 aberrations at or near the specimen plane in accordance with the present invention. [Figure 4] 1 illustrates an exemplary crew corrector with a single segmented multipole in accordance with the present disclosure. [Diagram 5] 4 shows an exemplary corrector as described in connection with FIGS. 1-3, in which a strong hexapole corresponds to a split of two hexapoles. [Figure 6] 1A and 1B respectively show a prior art crew-type corrector and a crew-type corrector according to the present disclosure in which one or more of the hexapoles is a split hexapole. [Figure 7] 1A and 1B respectively show a prior art crew-type corrector and a crew-type corrector according to the present disclosure in which one or more of the hexapoles is a split hexapole. [Figure 8] 1 shows a rose corrector with at least one split hexapole. [Figure 9] FIG. 1 illustrates the optical behavior of a rose corrector with two split hexapoles according to the present disclosure.

[0007] The same reference numbers refer to corresponding parts throughout the several views of the drawings. Generally, in the figures, elements that are likely to be included in a given example are shown with solid lines, while elements that are optional in a given example are shown with dashed lines. However, elements shown with solid lines are not essential to all examples of the present disclosure, and elements shown with solid lines may be omitted from particular examples without departing from the scope of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Disclosed herein is a compact corrector system for correcting spherical aberration of particle-optical lenses in charged particle microscope systems, including but not limited to SEM, STEM, TEM, and FIB. Specifically, the systems disclosed herein use multipoles (e.g., but not limited to, electromagnetic, electrostatic, split multipoles, etc.) to correct A2, C3, and / or D4 aberrations. An exemplary corrector system according to the present disclosure includes a strong hexapole that is positioned such that its center is misaligned with the beam crossover (e.g., the strong hexapole is positioned in the system, the beam is steered, or a combination thereof, such that the center of the strong hexapole is positioned 0.1-2 mm from the location of the beam crossover), and a weak hexapole (e.g., 10x, 50x, 100x, etc., smaller than the strong hexapole) is positioned downstream of the strong hexapole. In accordance with the present invention, the misalignment of the strong hexapole is in the direction of the weak hexapole. Because of this displacement, when a first voltage is applied to the strong hexapole, the strong hexapole generates a strong hexapole field when a first voltage is applied to it, and when the corrector module is used in a charged particle microscope system, the weak hexapole is positioned between the strong hexapole and a sample.

[0009] According to the present invention, the strong hexapole is positioned such that the crossover of the charged particle beam of the charged particle system does not pass through the center point of the strong hexapole (i.e., does not pass within 0.1, 0.2, 0.5, 1 mm, 1.2 mm, 1.5 mm, or 2 mm of the center of the strong hexapole) such that the strong hexapole field applies at least the combined A2 and D4 aberrations to the charged particle beam. A second voltage can then be applied to the weak hexapole such that the weak hexapole generates a weak hexapole field that applies at least the combined A2 and combined D4 aberrations to the charged particle beam of the charged particle microscope system. In some embodiments, the weak and strong hexapoles can be positioned, charged, or otherwise configured such that the two hexapole fields further apply a combined C3 aberration to the beam. In this manner, the net combination of aberrations applied to the charged particle beam by the weak and strong hexapole fields can be adjusted so that the charged particle beam has the desired A2, C3, and / or D4 aberrations at or near the sample plane. In this manner, a compact corrector according to the present disclosure can improve the resolution of a charged particle microscope. For example, a compact corrector according to the present disclosure can improve the resolution of a 30 kV beam SEM optical column by at least a factor of 2.5.

[0010] The present disclosure further describes various types of corrector systems disclosed, including split multipoles. A split multipole consists of two hexapoles separated by a distance (e.g., less than 20 mm), where the multipoles each consist of two or more electrodes having a thickness of less than 10 mm, 5 mm, 3 mm, or 1 mm. For example, when the multipole is a wafer multipole, such wafer multipoles each consist of two or more electrodes having a thickness of 1-100 μm. In some embodiments, such wafer hexapoles may correspond to and / or be constructed using the systems and methods disclosed in U.S. Patent Application No. XX / XXX,XXX, entitled CHARGED PARTICLE OPTICS COMPONENTS AND THEIR FABRICATION, filed July 22, 2022, which is incorporated herein by reference in its entirety. The split multipole is configured to generate a strong multipole field when a voltage (e.g., 100V-300kV) is applied to each of the wafer multipoles. By applying the same voltage to each of the multipoles, the combined electromagnetic fields generated by the two multipoles combine to provide a strong multipole effect. Because split multipoles consist of multipoles, split multipoles can be used to correct aberrations in charged particle beams with energies greater than 10 keV.

[0011] 1 is a diagram of an exemplary compact corrector 100 for correcting A2, C3, and / or D4 aberrations at or near the sample plane in accordance with the present invention. The exemplary compact multipole corrector 100 includes a strong hexapole 102 (e.g., a first hexapole, octupole, or dodecapole element) having an effective length L configured to generate a strong hexapole field when a first voltage is applied, and a weak hexapole 104 (e.g., a second hexapole, octupole, or dodecapole element) positioned downstream of the strong hexapole 102 when used in a charged particle system configured to generate a weak hexapole field when a second voltage is applied. The strengths and / or orientations of the strong and weak hexapoles can be adjusted to enable desired values ​​of their generated field contributions to A2, C3, and / or D4. In various embodiments, the strong hexapole 102 can be an electrostatic multipole having a length in the range of 0.01 to 10 mm (e.g., at least 5 mm), and the first voltage can be 0.1 kV to 30 kV. Additionally, the weak hexapole 104 is at least 30, 50, or 100 times weaker than the strong hexapole 102. As shown in FIG. 9, in some embodiments, the strong hexapole 102 can be a split hexapole consisting of two hexapoles separated by a distance of less than any of 100 mm, 10 mm, 1 mm, 100 μm, and 10 μm. Such a multipole can consist of two or more electrodes having a thickness of less than 10 mm, 5 mm, 3 mm, or 1 mm.

[0012] During operation of a charged particle system including the compact corrector 100, a charged particle beam 106 is directed along a central axis 108 to a first end 110 of the compact corrector. In accordance with the invention, the weak hexapole 104 is positioned, excited, and / or otherwise configured such that the weak hexapole field combines with the strong hexapole field to create a combined aberration that applies one or more of the A2, C3, and / or D4 aberration effects to the charged particle beam as it passes through the corrector 100. According to the invention, the combined aberration effect produced by the strong hexapole field contribution to one or more of the A2, C3, and / or D4 aberrations and the combination of the strong and weak hexapole fields can be such that the net result of the strong hexapole field contribution to one or more of the A2, C3, and / or D4 aberrations and the combined aberration effect is such that the value of one or more of the A2, C3, and / or D4 aberrations at the charged particle beam 106 at or near the sample plane has a desired value. In some embodiments, this can result in a charged particle beam 102 having zero or near zero A2, C3, and / or D4 aberrations when the charged particle beam 106 exits the corrector 100. Alternatively or additionally, the corrector may cause the charged particle beam 106 to have desired A2, C3, and / or D4 aberration values ​​when the charged particle beam 106 exits the corrector 100, which combines with other aberration effects of other optical elements downstream of the corrector 100 in the charged particle system such that the desired values ​​of A2, C3, and / or D4 aberrations are present in the charged particle beam 106 at the sample plane.

[0013] In prior art correctors, the component multipoles are positioned at the charged particle beam crossovers to counteract the aberrations. However, in the exemplary compact corrector 100, the strong hexapole 102 is positioned, or the charged particle beam 106 is adjusted, or a combination thereof, such that a displacement ε exists between the center 112 of the strong hexapole and the charged particle beam crossover 114. In this manner, the contributions of the strong hexapole field to the A2, C3, and D4 aberrations of the charged particle beam 106 are not aligned with the strong hexapole 102 and the charged particle beam crossover 114. Specifically, the contributions of the strong hexapole field to each of the A2, C3, and D4 aberrations to the charged particle beam 106 are each a function of the displacement ε. For example, in a model compact corrector 100 where the hexapole is a magnetic hexapole, using Hamilton's equations, the back-extrapolated contributions to each of the A2, C3, and D4 aberrations due to the corrector at location 114 can be shown as follows:

[0014]

number

[0015]

number

[0016] 1 shows the weak hexapole in close proximity to the objective lens 116 of the charged particle system. In some embodiments, the weak hexapole 104 may be positioned within the field of view of the objective lens 116 of the charged particle system and / or within the objective lens 116 of the charged particle system itself. However, one skilled in the art will appreciate that, in accordance with the present invention, the weak hexapole 104 may be placed anywhere between the strong hexapole 102 and the sample under study, so long as (1) it is possible to affect the beam 106 impinging on the sample, and (2) the voltages applied to the weak hexapole 104 and / or the strong hexapole 102 are adjusted such that the A2, C3, and / or D4 contributions from each of their corresponding hexapole fields combine to provide the desired net A2, C3, and / or D4 contributions to the beam 106.

[0017] Further, although not depicted in FIG. 1 , weak hexapole 104 may be positioned either upstream or downstream of a microscope beam scanning system (e.g., an AC scanning unit). For example, in one embodiment, weak hexapole 104 may be positioned downstream of a microscope scanning unit and configured to dynamically adjust the hexapole field it creates based on the path of the beam through weak hexapole 104. Additionally, in some embodiments of the present invention, weak hexapole 104 may be capable of being dynamically adjusted based on one or more components of the microscope system in which it is used. For example, weak hexapole 104 may be adjustable to compensate for beam rotation created by lenses in such a microscope system.

[0018] FIG. 1 further illustrates the compact corrector 100 as including an optional transfer lens 118 positioned downstream of the weak hexapole between the strong hexapole 102 and the weak hexapole 104. However, an embodiment of the corrector system 100 may include only one of these transfer lenses, additional transfer lenses, or no such transfer lenses. For example, in an embodiment of the invention, the corrector 100 may include a round lens 118 positioned between the strong hexapole and the weak hexapole, which is positioned, charged, or otherwise configured to apply a lensing effect to the charged particle beam 106 such that the magnitude of D4 aberration in the charged particle beam is affected to enable the charged particle beam to have a desired value of D4 aberration at the sample plane. In FIG. 1, the multipole corrector 100 is illustrated as a box including multiple optical components (i.e., multipoles and lenses). In various embodiments, these optical components may be encased or partially encased by a protective and / or support structure. Additionally, in embodiments that include such structures, one or more optical components may not be present within such structures.

[0019] 2 shows an exemplary charged particle microscope system 200 for inspection / imaging of components of a sample 202 according to the present invention, whose optical column includes a miniature corrector 100 for correcting A2, C3, and / or D4 aberrations at or near the sample plane. The exemplary charged particle microscope system 200 can include an electron microscope (EM) setup or an electron lithography setup configured to illuminate and / or otherwise bombard the sample 202 with a beam 204 of charged particles (usually an electron beam or an ion beam). In various embodiments, the charged particle microscope system 200 can be or include one or more different types of EM and / or charged particle microscopes, such as, but not limited to, a scanning electron microscope (SEM), a scanning transmission electron microscope (STEM), a transmission electron microscope (TEM), a charged particle microscope (CPM), a dual beam microscope system, etc. Additionally, in some embodiments, a TEM can also operate as a STEM. 2 illustrates an exemplary charged particle microscope system 200 as an SEM system 206. However, since the compact corrector 100 according to the present invention can consist of an electrostatic hexapole that can accommodate a wide range of excitations (e.g., including but not limited to 50 kV and 300 kV), the compact corrector can correct A2, C3, and / or D4 in TEM and STEM systems.

[0020] The exemplary charged particle microscope system 200 includes a charged particle source 208 (e.g., a thermionic electron source, a Schottky emission source, a field emission source, a liquid metal ion source, a plasma ion source, etc.) that emits a charged particle beam 204 along an emission axis 210 toward an acceleration lens 212. The emission axis 210 is a central axis that extends from the charged particle source 208 along the length of the exemplary charged particle microscope system 200 and through the sample 202.

[0021] The acceleration lens 212 accelerates / decels, focuses, and / or directs the charged particle beam 204 towards the focusing column 214. The focusing column 214 focuses the charged particle beam 204 for incidence on the sample 202. In addition, the focusing column 214 corrects and / or adjusts aberrations (e.g., geometric aberrations, chromatic aberrations) of the charged particle beam 204.

[0022] In Fig. 2, the focusing column 214 is shown as including a miniature corrector 100 for correcting A2, C3, and / or D4 aberrations at or near the sample plane in accordance with the present invention. That is, Fig. 2 shows a charged particle microscope system 200 including an SEM multipole corrector system 100 with a strong hexapole 102 and a weak hexapole 104, the center of the strong hexapole 102 being displaced by a displacement ε from the axial crossover 114 of the charged particle beam. The strong hexapole 102 may be configured to generate a strong hexapole field when a first voltage is applied, and the weak hexapole 104 may be configured to generate a weak hexapole field when a second voltage is applied. In some embodiments, the strong hexapole 102 may be a split hexapole consisting of two wafer hexapoles separated by a distance less than any of 100 mm, 10 mm, 1 mm, 100 μm, and 10 μm. One skilled in the art will understand how the weak hexapole 104 can be positioned, excited, and / or otherwise configured to provide a contribution to one or more of the A2, C3, and / or D4 aberrations in the charged particle beam 204 that is in combination with the strong hexapole field contribution to one or more of the A2, C3, and / or D4 aberrations in the charged particle beam 204. In this manner, by adjusting the positioning and excitation of the weak hexapole 104, the weak hexapole field contributions to one or more of the A2, C3, and / or D4 aberrations can be such that they combine with the strong hexapole field contribution to cause the charged particle beam 204 to have the desired A2, C3, and / or D4 aberrations at or near the sample plane.

[0023] The objective lens 216 is an optical element that focuses the charged particle beam 204 to a point on the sample 202. The objective lens 216 may include a single-pole piece lens, a magnetic electrostatic compound lens, an electrostatic detector objective lens, or another type of objective lens. An additional advantage of the compact corrector 100 according to the present invention is that it allows for an increased aperture angle of the charged particle beam. For example, the exemplary compact corrector 100 may allow for an aperture angle of the charged particle beam greater than 20 mrad.

[0024] FIG. 2 further illustrates the exemplary charged particle microscope system 200 as including a sample holder 218 that holds the sample 202. The exemplary charged particle microscope system 300 is also illustrated as including a detector system 220 configured to detect emissions from the sample 202 resulting from the charged particle beam 204 being incident on the sample 202. Additionally, although not illustrated in FIG. 2, the exemplary charged particle microscope system 200 may include an astigmatism correction and / or scanning coil for causing the charged particle beam 204 to scan the surface of the sample 202. For example, by operating the scanning coil, the direction of the charged particle beam 204 may be shifted so that it impinges on a different location of the sample 202. Those skilled in the art will appreciate that in a TEM or (S)TEM system, the detector system 220 may also include and / or consist of one or more detector positions below the sample.

[0025] 2 further illustrates the exemplary charged particle microscope system 200 as optionally including a computing device 230. Those skilled in the art will appreciate that the computing device 230 illustrated in FIG. 2 is merely exemplary and is not intended to limit the scope of the present disclosure. Computing systems and devices may include any combination of hardware or software capable of performing the specified functions, including computers, network devices, Internet appliances, PDAs, wireless telephones, controllers, oscilloscopes, amplifiers, etc. Computing device 230 may also be connected to other devices not shown, or may alternatively operate as a stand-alone system.

[0026] 3 is a diagram of an alternative embodiment of an exemplary compact corrector 300 for correcting A2, C3, and / or D4 aberrations at or near the sample plane in accordance with the present invention. The exemplary compact multipole corrector 300 includes a strong hexapole 102 having an effective length L configured to generate a strong hexapole field when a first voltage is applied, and a weak hexapole 104 downstream of the strong hexapole 102 when used in a charged particle system configured to generate a weak hexapole field when a second voltage is applied. During operation of a charged particle system including the compact corrector 300, a charged particle beam 302 is directed along a central axis 304 to a first end 306 of the compact corrector 300.

[0027] 3 further illustrates the compact corrector 300 as including an optional transfer lens 118 positioned downstream of the weak hexapole 104, on each side of the strong hexapole 102. While in some embodiments the AC scanning unit can be positioned upstream of the weak hexapole 104, FIG. 3 illustrates an embodiment in which the AC scanning unit 308 is positioned between the compact corrector 300 and the objective lens 310 of the microscope system.

[0028] FIG. 4 illustrates an exemplary crew-type corrector 400 with a single split multipole according to the present disclosure. Specifically, FIG. 4 illustrates a crew-type hexapole Cs corrector. As discussed above, in some embodiments, a strong multipole may correspond to a split multipole 402 consisting of two wafer hexapoles 404 having a thickness d and separated by a distance (e.g., less than 20 mm). According to the present invention, no optical components (lenses, multipoles, etc.) are positioned between the component wafer multipoles 404 for a split multipole. If the split multipole 402 has a length L, the separation can therefore be written as L-2d. A wafer multipole consists of two or more electrodes having a thickness of less than 10 mm, 5 mm, 3 mm, or 1 mm.

[0029] 4 illustrates the crew corrector 400 as further comprising a first transfer lens 406 and a second transfer lens 408, where the first transfer lens 406 applies a focusing effect to the charged particle beam 410 passing through the corrector 400, causing a crossover of the charged particle beam between the two wafer multipoles 404 that are components of the split multipole 402. Although FIG. 4 illustrates the crossover as being equidistant for each component wafer multipole, in other embodiments (such as the embodiment illustrated in FIG. 5), the first transfer lens 406 can be configured to apply a focusing effect that causes the crossover of the charged particle beam 410 to not be equidistant for each component wafer multipole 404.

[0030] 5 illustrates an exemplary corrector 500 as described in connection with FIGS. 1-3, in which a strong hexapole 502 corresponds to a split hexapole 504 consisting of two wafer hexapoles 506. FIG. 5 illustrates the corrector 500 including three transfer lenses 508 and a weak hexapole 510. As discussed above, the initial transfer lens 512 applies a focusing effect to the charged particle beam 514 passing through the corrector 500, causing a non-equidistant crossover between the two wafer multipoles 506 of the split multipole 504. As discussed above, one will understand how the weak hexapole 510 can be positioned, excited, and / or otherwise configured such that the weak hexapole field it generates makes a contribution to one or more of the A2, C3, and / or D4 aberrations in the charged particle beam 514 that is in combination with the strong hexapole field contribution to one or more of the A2, C3, and / or D4 aberrations in the charged particle beam 514. In this manner, by adjusting the positioning and excitation of the weak hexapole 510, the weak hexapole field contributions to one or more of the A2, C3, and / or D4 aberrations can be such that they combine with the strong hexapole field contribution to cause the charged particle beam 514 to have the desired A2, C3, and / or D4 aberrations at or near the sample plane.

[0031] 6 and 7 show crew-type correctors 600 and 700 according to the present disclosure, where one or more of the hexapoles are split hexapoles. Specifically, FIG. 6 shows a corrector with two strong hexapoles 602 with a single transfer lens 604 positioned at the axial crossover of the charged particle beam 606 equidistant from the two hexapoles 602. However, as shown in FIG. 7, according to the present invention, such crew-type correctors can also be made with one or more split hexapoles. For example, FIG. 7 shows a crew-type corrector 700 according to the present invention, where both strong hexapoles 702 are split hexapoles 704. However, one skilled in the art will understand that in some embodiments, only one of the strong hexapoles 702 can be a split hexapole 704. FIG. 7 also shows the corrector 700 as including a single transfer lens 706 positioned at the axial crossover of the charged particle beam 708 equidistant from the two split hexapoles 704.

[0032] FIG. 8 shows a Rose type corrector with at least one split hexapole. 8 illustrates a rose-type corrector 800 in which one of the two strong hexapoles 802 corresponds to a split hexapole 804 made of two wafer multipoles 806. However, one skilled in the art would understand how corrector 800 could be constructed with both strong hexapoles 802 corresponding to split hexapole 804. Corrector 800 is shown as having two transfer lenses 808 positioned between split hexapole 804.

[0033] FIG. 9 is a diagram 900 illustrating the optical behavior of a rose corrector 000 with two split hexapoles according to the present disclosure. Specifically, the diagram 900 illustrates the optical behavior to account for aberrations present in a rose corrector 800 with two split hexapoles. FIG. 9 illustrates the behavior of an axial ray 902 passing through an exemplary rose corrector 800 where two hexapoles are electrostatic split hexapoles 904 according to the present invention. Specifically, FIG. 9 illustrates the split hexapole 904 as consisting of two wafer hexapoles having a length L and a thickness d, with the same charge applied to each of the wafer hexapoles. For example, if the wafer hexapole is 2 mm thick, the length of the split hexapole may be 12 mm and the voltage applied to each wafer hexapole may be ±170 V. In various embodiments, the split hexapole 904 may be configured to generate small dipole and / or quadrupole fields in addition to the hexapole field. Without limiting this disclosure, one of ordinary skill in the art would understand the compensator strength of the rose compensator 800 to be equivalent to the following:

[0034]

number

[0035] Although FIGS. 4-9 show split multipoles included within some example corrector systems, those skilled in the art will understand how the split multipole technology described herein can be included in other corrector systems as a replacement for any general multipole element where second order effects of the generated hexapole field are important.

[0036] Examples of inventive subject matter according to the present disclosure are described in the paragraphs listed below.

[0037] A1. A compact corrector module for a charged particle microscope system, the corrector module comprising: a strong hexapole configured to generate a strong hexapole field when a first voltage is applied, the strong hexapole positioned such that a crossover of a charged particle beam of the charged particle system does not pass through a center of the strong hexapole, causing the strong hexapole field to apply at least the A2 and D4 aberrations to the charged particle beam of the charged particle microscope system; and a weak hexapole positioned between the strong hexapole and a sample when used in the charged particle microscope system, the weak hexapole generating a weak hexapole field that applies at least the combined A2 and combined D4 aberrations to the charged particle beam of the charged particle microscope system when a second voltage is applied to the weak hexapole.

[0038] A1.1. The compact corrector module described in paragraph A1, wherein the combined application of the A2 aberration and the combined A2 aberration to the charged particle beam results in the A2 aberration of the charged particle beam being zero or near zero at or near the sample plane.

[0039] A1.2. The compact corrector module of any one of paragraphs A1-A1.1, wherein the combined application of the D4 aberration and the combined D4 aberration to the charged particle beam results in the D4 aberration of the charged particle beam being zero or near zero at or near the sample plane.

[0040] A1.3. A compact corrector module described in any one of paragraphs A1 to A1.2, wherein the strong hexapole field further applies a C3 aberration to the charged particle beam of the charged particle microscope system and the weak hexapole field further applies a combined C3 aberration to the charged particle beam of the charged particle microscope system.

[0041] A1.3.1. The compact corrector module described in paragraph A1.3, wherein the combined application of the C3 aberration and the combined C3 aberration to the charged particle beam results in the C3 aberration of the charged particle beam being zero or near zero at or near the specimen plane.

[0042] A2. The compact corrector module of any one of paragraphs A1-A1.3.1, wherein the second voltage is determined and selected based on a distance between a crossover of the charged particle beam and a center of the strong hexapole.

[0043] A2.1. The compact corrector module described in paragraph A2, wherein the second voltage is determined and selected based on the distance between the crossover of the charged particle beam and the center of the strong hexapole such that one or more of the A2, C3, and D4 aberrations caused by the weak multipole field are a combination with the A2, C3, and D4 aberrations caused by the strong multipole field.

[0044] A3. The compact corrector of any one of paragraphs A1-A2.1, wherein the weak hexapole is at least 50 or 100 times weaker than the strong hexapole.

[0045] A4. The compact corrector of any one of paragraphs A1-A3, wherein the weak hexapole is positioned within the objective lens when used in a charged particle system.

[0046] A5. The compact corrector of any one of paragraphs A1-A4, wherein the weak hexapole is positioned within the field of view of the objective lens.

[0047] A6. The compact corrector of any one of paragraphs A1 to A5, wherein the charged particle microscope is one of a scanning electron microscope (SEM), a scanning transmission electron microscope (STEM), and a transmission electron microscope (TEM).

[0048] A7. The compact corrector of any one of paragraphs A1-A6, wherein the strong hexapole is an electrostatic hexapole or an electromagnetic hexapole.

[0049] A7.1. The compact corrector of paragraph A7, wherein the strong hexapole has an (effective) length of at least 5 mm.

[0050] A8. The compact compensator of any one of paragraphs A1-A7.1, wherein the compensator module is a probe compensator.

[0051] A9. The compact corrector of any one of paragraphs A1-A8, further including a transfer lens positioned between the strong hexapole and the weak hexapole.

[0052] A9.1. The compact corrector of paragraph A9, further comprising an additional transfer lens positioned downstream of the weak hexapole.

[0053] A10. The compact corrector of any one of paragraphs A1-A9, wherein the first voltage applied to the strong hexapole is 50-300 kV.

[0054] A11. The miniature corrector of any one of paragraphs A1-A10, wherein the miniature corrector module is configured to enable an aperture angle of the charged particle beam of the charged particle microscope to be greater than 20 mrad.

[0055] A12. The compact corrector of any one of paragraphs A1-A11, further comprising a focusing lens positioned upstream of the strong hexapole when used in a charged particle system.

[0056] A13. The compact corrector of any one of paragraphs A1-A12, wherein the compact corrector includes only one strong hexapole.

[0057] B1. A charged particle system comprising: a sample holder configured to hold a sample; a charged particle source configured to emit a charged particle beam toward the sample; an optical column configured to direct the charged particle beam so that it is incident on the sample, the optical column comprising: a strong hexapole configured to generate a strong hexapole field when a first voltage is applied to it, the strong hexapole positioned such that a crossover of the charged particle beam does not pass through a center of the strong hexapole, causing the strong hexapole field to apply at least A2 and D4 aberrations to the charged particle beam; and a weak hexapole positioned between the strong hexapole and the sample, the weak hexapole generating a weak hexapole field that applies at least a combined A2 and a combined D4 aberration to the charged particle beam when a second voltage is applied to the weak hexapole; and a detector system configured to detect emissions resulting from the sample being irradiated by the charged particle beam.

[0058] B1.1. The compact corrector module of paragraph B1, wherein the combined application of the A2 aberration and the combined A2 aberration to the charged particle beam results in the A2 aberration of the charged particle beam being zero or near zero at or near the sample plane.

[0059] B1.2. The compact corrector module of any one of paragraphs B1-B1.1, wherein the combined application of the D4 aberration and the combined D4 aberration to the charged particle beam results in the D4 aberration of the charged particle beam being zero or near zero at or near the sample plane.

[0060] B1.3. The compact corrector module of any one of paragraphs B1-B1.2, wherein the strong hexapole field further applies a C3 aberration to the charged particle beam of the charged particle microscope system and the weak hexapole field further applies a combined C3 aberration to the charged particle beam of the charged particle microscope system.

[0061] B1.3.1. The compact corrector module described in paragraph B1.3, wherein the combined application of the C3 aberration and the combined C3 aberration to the charged particle beam results in the C3 aberration of the charged particle beam being zero or near zero at or near the specimen plane.

[0062] B2. The compact corrector module of any one of paragraphs B1-B1.3.1, wherein the second voltage is determined and selected based on a distance between a crossover of the charged particle beam and a center of the strong hexapole.

[0063] B2.1. The compact corrector module described in paragraph B2, wherein the second voltage is determined and selected based on the distance between the crossover of the charged particle beam and the center of the strong hexapole such that one or more of the A2, C3, and D4 aberrations caused by the weak multipole field are a combination with the A2, C3, and D4 aberrations caused by the strong multipole field.

[0064] B3. The compact corrector of any one of paragraphs B1-B2.1, wherein the weak hexapole is at least 50 or 100 times weaker than the strong hexapole.

[0065] B4. The compact corrector of any one of paragraphs B1-B3, wherein the weak hexapole is positioned within the objective lens when used in a charged particle system.

[0066] B5. The compact corrector of any one of paragraphs B1-B4, wherein the weak hexapole is positioned within the field of view of the objective lens.

[0067] B6. The compact corrector of any one of paragraphs B1-B5, wherein the charged particle microscope is one of a scanning electron microscope (SEM), a scanning transmission electron microscope (STEM), and a transmission electron microscope (TEM).

[0068] B7. The compact corrector of any one of paragraphs B1-B6, wherein the strong hexapole is an electrostatic hexapole or an electromagnetic hexapole.

[0069] B7.1. The compact corrector of paragraph B7, wherein the strong hexapole has a length of at least 5 mm.

[0070] B8. The miniature compensator of any one of paragraphs B1-B7.1, wherein the compensator module is a probe compensator.

[0071] B9. The compact corrector of any one of paragraphs B1-B8, further including a transfer lens positioned between the strong hexapole and the weak hexapole.

[0072] B9.1. The compact corrector of paragraph B9, further comprising an additional transfer lens positioned downstream of the weak hexapole.

[0073] B10. The compact corrector of any one of paragraphs B1-B9, wherein the first voltage applied to the strong hexapole is between 50 and 300 kV.

[0074] B11. The miniature corrector of any one of paragraphs B1-B10, wherein the miniature corrector module is configured to enable an aperture angle of the charged particle beam of the charged particle microscope to be greater than 20 mrad.

[0075] B12. The compact corrector of any one of paragraphs B1-B11, further comprising a focusing lens positioned upstream of the strong hexapole when used in a charged particle system.

[0076] B13. The compact corrector of any one of paragraphs B1-B12, wherein the compact corrector includes no more than one strong hexapole.

[0077] C1. An optical corrector module for a charged particle column, the optical corrector module comprising a split multipole consisting of two wafer multipoles separated by a distance of less than 100 mm, each wafer multipole comprising at least two electrodes positioned to partially define a beam path through the wafer multipole, each of the electrodes comprising a first surface that faces upstream of the charged particle beam when used in the charged particle column and a second surface that faces downstream of the charged particle beam when used in the charged particle column, and a thickness between the first and second surfaces of each of the electrodes is less than 3 mm.

[0078] C1.1. The optical corrector module of paragraph C1, wherein the split multipole is configured to generate a strong multipole field when a first voltage is applied to each of the wafer multipoles.

[0079] C1.1.1. The optical corrector module of paragraph C1.1, wherein the two wafer multipoles of the split multipole are separated by a distance of any one of 10 mm, 1 mm, 100 μm, and 10 μm.

[0080] C1.2. The optical corrector module of any one of paragraphs C1-C1.1.1, wherein the thickness between the first surface and the second surface of each of the electrodes is less than 100 μm.

[0081] C1.2.1. The optical corrector module of paragraph C1.2, wherein a thickness between the first surface and the second surface of each of the electrodes is 1 to 100 μm.

[0082] C1.2.2. The optical corrector module of paragraph C1.2 or C1.2.1, wherein the thickness between the first surface and the second surface of each of the electrodes is less than any of 10 mm, 1 mm, 100 μm, and 10 μm.

[0083] C1.3. The optical corrector module of any one of paragraphs C1-C1.2.2, wherein the distance between the wafer multipoles in a split multipole is less than 20 mm.

[0084] C1.4. The optical corrector module of any one of paragraphs C1-C1.3, wherein a third surface of each of the electrodes that faces the charged particle beam as the charged particle beam passes through the wafer multipole has a maximum surface roughness of Ra 0.05 μm.

[0085] C1.5. The optical corrector module of any one of paragraphs C1-C1.4, wherein the individual wafer multipoles are configured for use with charged particle beam energies greater than 10 keV.

[0086] C1.6. The optical corrector module of any one of paragraphs C1-C1.4, wherein the voltage applied to the wafer hexapole is between 100V and 300kV.

[0087] C1.7. The optical corrector module of any one of paragraphs C1-C1.6, wherein the voltage applied to each of the wafer hexapoles is the same.

[0088] C1.8. The optical corrector module of any one of paragraphs C1-C1.7, wherein no optical components are positioned between the two wafer multipoles along the charged particle beam path.

[0089] C1.9. The optical corrector module of any one of paragraphs C1-C1.8, wherein the split multipole is a split hexapole configured to generate a strong hexapole field when a first voltage is applied to each of the wafer multipoles.

[0090] C1.9.1. The optical corrector module of paragraph C1.9, wherein each of the wafer multipoles is a wafer hexapole configured to generate a hexapole field when a voltage is applied to each of the wafer hexapoles.

[0091] C1.10. The optical corrector module of any one of paragraphs C1-C1.9.1, comprising a first transfer lens and a second transfer lens, the first transfer lens being an optical element immediately upstream of the split multipole element and the second transfer lens being an optical element immediately downstream of the split multipole element.

[0092] C1.10.1. The optical corrector module of paragraph C1.10, wherein a first on-axis ray applies a focusing effect that causes a crossover of the charged particle beam between two wafer multipoles that are parts of a split multipole.

[0093] C1.10.1.1. The optical corrector module of paragraph C1.10.1, wherein the crossover of the charged particle beam is equidistant for each component wafer multipole.

[0094] C1.10.1.2. An optical corrector module described in paragraph C1.10.1 in which the crossover of the charged particle beam is not equidistant for each component wafer multipole.

[0095] C2. The optical corrector module of any one of paragraphs C1-C1.10, wherein the segmented multipole is a strong hexapole.

[0096] C2.0.1. The optical corrector module of paragraph C2, wherein the optical corrector module is a crew-type hexapole Cs corrector.

[0097] C2.0.2. The optical corrector module of any one of paragraphs C2-C2.0.1, further comprising a weak hexapole positioned between the strong hexapole and the sample when the corrector is used in a charged particle column.

[0098] C2.1. The optical corrector module described in paragraph C2, wherein the split hexapole is positioned such that crossover of the charged particle beam does not pass through a center of the split hexapole and causes the split hexapole field to apply at least the A2 and D4 aberrations to the charged particle beam when used in the charged particle column.

[0099] C2.1.1. The optical corrector module of paragraph C2.1, wherein when a second voltage is applied to the weak hexapole, the weak hexapole generates a weak hexapole field that applies at least a combined A2 aberration and a combined D4 aberration to the charged particle beam.

[0100] C2.1.1.1. The optical corrector module described in paragraph C2.1.1, wherein the combined application of the A2 aberration and the combined A2 aberration to the charged particle beam results in the A2 aberration of the charged particle beam being zero or near zero at or near the sample plane.

[0101] C2.1.1.2. The optical corrector module of any one of paragraphs C2.1.1 to C2.1.1.1, wherein the combined application of the D4 aberration and the combined D4 aberration to the charged particle beam results in the D4 aberration of the charged particle beam being zero or near zero at or near the sample plane.

[0102] C2.1.3. The optical corrector module of any one of paragraphs C2 through C2.1.1.2, wherein the strong hexapole field further applies a C3 aberration to the charged particle beam of the charged particle microscope system and the weak hexapole field further applies a combined C3 aberration to the charged particle beam of the charged particle microscope system.

[0103] C2.1.3.1. The optical corrector module of paragraph C2.1.3, wherein the combined application of the C3 aberration and the combined C3 aberration to the charged particle beam results in the C3 aberration of the charged particle beam being zero or near zero at or near the specimen plane.

[0104] C2.2. The optical corrector module of any one of paragraphs CA2.1.1 to C2.1.3.1, wherein the second voltage is determined and selected based on a distance between a crossover of the charged particle beam and a center of the split hexapole.

[0105] C2.2.1. The optical corrector module described in paragraph C2.2, wherein the second voltage is determined and selected based on the distance between the crossover of the charged particle beam and the center of the strong hexapole such that one or more of the A2, C3, and D4 aberrations caused by the weak multipole field are a combination with the A2, C3, and D4 aberrations caused by the strong multipole field.

[0106] C2.2.2. The optical corrector module of any one of paragraphs C2.2-C2.2.1, wherein the weak hexapole is at least 50 or 100 times weaker than the strong hexapole.

[0107] C2.3. The optical corrector module of any one of paragraphs C2-C2.2.2, wherein the weak hexapole is positioned within the objective lens when used in a charged particle system.

[0108] C2.4. The optical corrector module of any one of paragraphs C2-C2.3, wherein the weak hexapole is positioned within the field of view of the objective lens.

[0109] C2.5. The optical corrector module of any one of paragraphs C2-C2.4, wherein the strong hexapole is an electrostatic hexapole.

[0110] C2.6. The optical corrector module of paragraph C2.5, wherein the strong hexapole has an (effective) length of at least 5 mm.

[0111] C2.8. The optical corrector module of any of paragraphs C2-C2.7, further including a transfer lens positioned between the strong hexapole and the weak hexapole.

[0112] C2.8.1. The optical corrector module of paragraph C2.8, further including an additional transfer lens positioned downstream of the weak hexapole.

[0113] C2.9. The optical corrector module of any one of paragraphs C2-C9, wherein the first voltage applied to the strong hexapole is between 50 and 300 kV.

[0114] C2.10. The optical corrector module of any one of paragraphs C2-C2.9, wherein the optical corrector module is configured to enable an aperture angle of the charged particle beam of the charged particle microscope to be greater than 20 mrad.

[0115] C2.11. The optical corrector module of any one of paragraphs C2-C2.10, further comprising a focusing lens positioned upstream of the strong hexapole when used in a charged particle system.

[0116] C3. The optical corrector module of any one of paragraphs C1-C2.11, wherein the corrector further comprises an additional multipole element.

[0117] C3.1. The optical corrector module of paragraph C3, wherein the additional multipole is a split multipole.

[0118] C3.1.1. The additional multipole consists of two additional wafer multipoles separated by a distance of less than 10 mm, and each additional wafer multipole is at least two additional electrodes positioned to partially define a beam path through the additional wafer multipole, each of the additional electrodes comprising: a first surface that, when used in a charged particle column, faces upstream of a charged particle beam; The optical corrector module of paragraph C3.1, wherein when used in a charged particle column, the optical corrector module comprises: a second surface that faces downstream of the charged particle beam.

[0119] C3.1.2. The optical corrector module of any one of paragraphs C3.1-C3.1.1, wherein the thickness between the first surface and the second surface of each of the additional electrodes is less than 3 mm.

[0120] C3.1.3. The optical corrector module of any one of paragraphs C3.1-C3.1.1, wherein the thickness between the first surface and the second surface of each of the additional electrodes is less than 100 μm.

[0121] C3.2. The optical corrector module of any one of paragraphs C3-C3.1.3, wherein an additional multipole is positioned downstream of the split multipole when used in a charged particle system.

[0122] C3.3. The optical corrector module of any one of paragraphs C3-C3.1, wherein an additional multipole is positioned upstream of the split multipole when used in a charged particle system.

[0123] C3.4. The optical corrector module of any one of paragraphs C3-C3.3, wherein an additional multipole is positioned downstream of the split multipole when used in a charged particle system.

[0124] C3.5. The optical corrector module of any one of paragraphs C3-C3.4, wherein there is no multipole positioned between the split multipole and the additional multipole.

[0125] C3.6. The optical corrector module of any one of paragraphs C3-C3.5, comprising a transfer lens positioned between the split multipole and the additional multipole.

[0126] C3.6.1. The optical corrector module of paragraph C3.6, wherein the transfer lens is positioned at an axial crossover of the charged particle beam.

[0127] C3.6.2. The optical corrector module of any one of paragraphs C3.6-C3.6.1, wherein the axial crossover of the charged particle beam is equidistant for each of the split multipoles and the additional multipoles.

[0128] C3.6.3. An optical corrector module according to any one of paragraphs C3.6 to C3.6.2, wherein the charged particle beam is not a collimated beam when passing through a split multipole when the optical corrector module is used in a charged particle system.

[0129] C3.7. The optical corrector module of any one of paragraphs C3-C3.5, comprising a first transfer lens and a second transfer lens positioned between the split multipole element and the additional multipole element.

[0130] C3.7.1. The optical corrector module of paragraph C3.7, wherein the first transfer lens is positioned upstream of an axial crossover of the charged particle beam and the second transfer lens is positioned downstream of the axial crossover of the charged particle beam.

[0131] C3.7.2. The optical corrector module of any one of paragraphs C3.7-C3.7.1, wherein the axial crossover of the charged particle beam is equidistant for each of the split multipoles and the additional multipoles.

[0132] C3.7.3. The optical corrector module of any one of paragraphs C3.7-C3.7.2, wherein an axial crossover of the charged particle beam is equidistant to each of the first transfer lens and the second transfer lens.

[0133] C3.7.4. The optical corrector module of any one of paragraphs C3.7-C3.7.3, wherein the charged particle beam is a collimated beam when passing through the split multipole when the optical corrector module is used in a charged particle system.

[0134] C3.7.5. An optical corrector module as described in any one of paragraphs C3.7 to C3.7.3, wherein the charged particle beam is a substantially parallel beam when passing through the split multipole when the optical corrector module is used in a charged particle system.

[0135] C3.8. The optical corrector module of any one of paragraphs C3-C3.7.5, wherein the split multipole and the additional multipole are both electrostatic multipoles.

[0136] C3.9. The optical corrector module of any one of paragraphs C3-C3.8, wherein the split multipole and the additional multipole are both hexapoles.

[0137] C4. The optical corrector module of any of paragraphs C2-C2.6, wherein the optical corrector module is a probe corrector.

[0138] C5. The optical corrector module of any one of paragraphs C1-C4, wherein a corrector strength of the optical corrector module corresponds to the following relationship:

[0139]

number

[0140] D1. A charged particle system comprising: a sample holder configured to hold a sample; a charged particle source configured to emit a charged particle beam toward the sample; an optical column configured to direct the charged particle beam so that it is incident on the sample, the optical column including an optical corrector module described in any one of paragraphs C1-C5; and a detector system configured to detect emissions resulting from the sample being irradiated by the charged particle beam.

[0141] E1. Use of a corrector module according to any one of paragraphs A1-A13 and C1-C5.

[0142] F1. Use of a charged particle system according to any one of paragraphs B1-B13 and D1.

Claims

1. A charged particle microscope system, A sample holder configured to hold a sample, A charged particle source configured to emit a charged particle beam toward the aforementioned sample, An optical column configured to direct the charged particle beam so that the charged particle beam is incident on the sample, comprising an optical column including a miniature compensator module, Detector system and The miniature compensator module is equipped with, A strong multipole configured to generate a strong multipole field when a first voltage is applied, wherein the crossover of the charged particle beam does not pass through the center of the strong multipole, and the strong multipole field is positioned to cause at least A2 aberration and D4 aberration to be applied to the charged particle beam. A weak multipole positioned between the strong multipole and the sample plane, wherein when a second voltage is applied to the weak multipole, the weak multipole generates a weak multipole field that applies at least combined A2 aberration and combined D4 aberration to the charged particle beam, The detector system is configured to detect emissions resulting from the irradiation of the sample by the charged particle beam, The number of strong multipoles in the aforementioned miniature compensator module is exactly one. The aforementioned miniature compensator module does not include any multipoles stronger than the weak multipoles, in addition to the strong multipoles. The combination of applying the A2 aberration and the combined A2 aberration to the charged particle beam results in the charged particle beam having the desired A2 aberration in the sample plane. A charged particle microscope system in which the application of the D4 aberration and the combined D4 aberration to the charged particle beam results in the charged particle beam having a desired D4 aberration in the plane of the sample.

2. The aforementioned strong multipole field further applies C3 aberration to the charged particle beam of the charged particle microscope system, The aforementioned weak multipole field further applies combined C3 aberration to the charged particle beam of the charged particle microscope system, The charged particle microscope system according to claim 1, wherein the combination of applying the C3 aberration and the combined C3 aberration to the charged particle beam results in the charged particle beam having a desired C3 aberration in the sample plane.

3. The charged particle microscope system according to claim 2, wherein the charged particle microscope system is configured to apply the second voltage, the second voltage being based on the distance between the crossover of the charged particle beam and the center of the strong multipole such that one or more of the combined A2 aberration, the combined C3 aberration, and the combined D4 aberration caused by the weak multipole field is in combination with the A2, C3, and D4 aberrations caused by the strong multipole field.

4. The charged particle microscope system according to claim 1, wherein the charged particle microscope system is configured to apply the first voltage and the second voltage such that the weak multipole is at least 50 times weaker than the strong multipole.

5. The charged particle microscope system according to claim 1, wherein the weak multipole is positioned within the objective lens of the optical column of the charged particle microscope system.

6. The charged particle microscope system according to claim 1, wherein the weak multipole is positioned within the field of view of the objective lens of the optical column of the charged particle microscope system.

7. The charged particle microscope system according to claim 1, further comprising a circular lens positioned between the strong multipole and the weak multipole, wherein the circular lens is positioned, charged, or otherwise configured such that the lensing effect of the circular lens causes to adjust the magnitude of the D4 aberration, which in combination with the combined D4 aberration results in the charged particle beam having a desired D4 aberration in the sample plane.

8. The charged particle microscope system according to claim 1, wherein the strong multipole is an electrostatic multipole.

9. The charged particle microscope system according to claim 8, wherein the strong multipole has a length of at least 5 mm.

10. The charged particle microscope system according to claim 1, wherein the strong multipole is a strong hexapole and the weak multipole is a weak hexapole.

11. The charged particle microscope system according to claim 1, wherein the charged particle microscope system is configured to apply the first voltage to the strong multipole such that the first voltage is between 0.1 and 30 kV.

12. The charged particle microscope system according to claim 1, wherein the miniature compensator module is configured to allow the aperture angle of the charged particle beam of the charged particle microscope system to be greater than 20 mrad.

13. The charged particle microscope system according to claim 1, wherein the charged particle microscope system is configured to apply the first voltage to the strong multipole such that the first voltage is between 50 and 300 kV, and the weak multipole is at least 50 or 100 times weaker than the strong multipole.

14. A miniature compensator module for a charged particle microscope system, wherein the miniature compensator module is A strong multipole configured to generate a strong multipole field when a first voltage is applied, wherein the crossover of the charged particle beam of the charged particle microscope system does not pass through the center of the strong multipole, and the strong multipole field is positioned to cause at least A2 aberration and D4 aberration to be applied to the charged particle beam. When the miniature compensator module is used in the charged particle microscope system, a weak multipole is positioned between the strong multipole and the sample plane, and when a second voltage is applied to the weak multipole, the weak multipole is configured to generate a weak multipole field that applies at least combined A2 aberration and combined D4 aberration to the charged particle beam. A miniature compensator module comprising, wherein the strong multipole is the only multipole in the miniature compensator module that is stronger than the weak multipole.

15. The miniature compensator module according to claim 14, wherein the combination of applying the A2 aberration and the combined A2 aberration to the charged particle beam results in the charged particle beam having a desired A2 aberration in the sample plane, and the combination of applying the D4 aberration and the combined D4 aberration to the charged particle beam results in the charged particle beam having a desired D4 aberration in the sample plane.

16. The aforementioned strong multipole field further applies C3 aberration to the charged particle beam of the charged particle microscope system, The aforementioned weak multipole field further applies combined C3 aberration to the charged particle beam of the charged particle microscope system, The miniature compensator module according to claim 14, wherein the combination of applying the C3 aberration and the combined C3 aberration to the charged particle beam results in the charged particle beam having a desired C3 aberration in the sample plane.

17. The miniature compensator module according to claim 16, wherein the miniature compensator module is configured to operate such that one or more of the combined A2 aberration, the combined C3 aberration, and the combined D4 aberration caused by the weak multipole field are in combination with the A2, C3, and D4 aberrations caused by the strong multipole field.

18. The miniature compensator module according to claim 14, further comprising a circular lens positioned between the strong multipole and the weak multipole, wherein the circular lens is positioned, charged, or otherwise configured such that the lensing effect of the circular lens causes to adjust the magnitude of the D4 aberration, which in combination with the combined D4 aberration results in the charged particle beam having a desired D4 aberration in the sample plane.

19. The compact compensator module according to claim 14, wherein the strong multipole is an electrostatic multipole.

20. The compact compensator module according to claim 14, wherein the strong multipole is a strong hexapole and the weak multipole is a weak hexapole.

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