Scanning transmission electron microscope resolution and contrast improvement

Abstract

Methods for improving charged particle beam imaging may comprise a forming part, an acquiring part, and a producing part. In the forming part, a focused beam of charged particles may be formed through a spherical aberration (Cs) correction membrane. In the acquiring part, a plurality of first images of a sample on a sample stage may be acquired through a segmented detector, based upon an application of the focused beam of charged particles to the sample. In the producing part, one or more second images may be produced based upon the plurality of first images using an integrated differential phase contrast (iDPC) technique.

Description

SCANNING TRANSMISSION ELECTRON MICROSCOPE RESOLUTION ANDCONTRAST IMPROVEMENTCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application no. 63 / 665,837, filed June 28, 2024. The entire contents of the aforementioned application is incorporated by reference herein.FIELD OF THE INVENTION

[0002] The mechanisms and methods discussed herein pertain to improvements in Scanning Transmission Electron Microscope (STEM) technologies, particularly in the improvement of resolution and contrast.BACKGROUND OF THE INVENTION

[0003] A basic feature of charged-particle microscopy over time has been the use of electromagnetic fields (such as electrostatic fields and / or magnetic fields) to influence the trajectory of charged particles (e.g., electrons), in a manner analogous to the way in which material lenses may be used to influence the trajectory of light. In other words, where optical microscopy uses material lenses to focus light, charged-particle microscopy uses electromagnetic fields to focus charged particles. Some common varieties of charged-particle microscopy include Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM) and Scanning TEM (STEM).

[0004] In both optical microscopy and charged-particle microscopy, spherical aberration (Cs) can arise in the lenses involved (the material lenses of the former, and the electromagnetic lenses of the latter). If Cs is not corrected, resolution of charged-particle microscopes may ultimately suffer. If Cs is corrected, resolution of charged-particle microscopes may be improved.

[0005] In one recent example, without implementation of Cs correction, resolution was observed to be less than about 1.6 Angstroms (A), in the context of microscopy based on Scanning Field Emission Gun (S-FEG) and / or Extreme-brightness Field Emission Gun (XFEG), and resolution was also observed to be less than about 1.4 A (in the context of microscopy based upon Extreme-Brightness Cold Field Emission Gun (X-CFEG)). In comparison, with implementation of Cs correction, resolution was observed to be about 0.9 A.

[0006] Various methods for correcting spherical aberration may have advantages and disadvantages. Multipole correctors may have minimum noise, but may be large and expensive. Holography correctors may have low noise, but may require three condensers. Programmable phase plates may be relatively flexible and may have low noise, but may also be subject to relatively complicated alignment and fabrication.

[0007] Cs correction membranes (such as phase modifying membranes) may advantageously reduce or minimize Cs. However, non-elastic scattering (e.g., non-elastic electron scattering) may result in relatively low contrast and / or relatively low signal-to-noise (SNR).SUMMARY OF THE INVENTION

[0008] The inventors have discovered that some of the disadvantageous properties of Cs correction membranes may be overcome by combining the use of Cs correction membranes with Integrated Differential Phase Contrast (iDPC) technique (for example, at a STEM detector). Such iDPC techniques may be used in situations involving relatively low-dose imaging (which may be significant for materials that are sensitive to the charged-particle beams involved, or for materials that are prone to charging upon exposure to a beam).

[0009] The inventors have determined that the use of iDPC may improve the relatively low contrast and / or relatively low SNR observed by the use of Cs correction membranes alone. iDPC techniques may offer improved contrast for low-atomic-number (low-Z) elements, such as lithium, (with a reduced dependence upon factors such as defocus and thickness), and iDPC techniques may also offer higher SNR ratios compared to annular bright field images (e.g., of annular bright- field scanning transmission electron microscopy (ABF-STEM)). Meanwhile, the inventors have additionally determined that the use of Cs correction membranes may address spherical aberration observed by the use of iDPC techniques alone. The combination of Cs correction membranes and iDPC techniques appears to notably boost contrast in high-resolution STEM (HR-STEM) systems (e.g., to enhance HR-STEM peaks).

[0010] Accordingly, as disclosed further herein, there appears to be a synergy between the use of Cs correction membranes in combination with the use of iDPC techniques, such as in HR-STEM systems. The combination of Cs correction membranes and the use of iDPC techniques appears toadvantageously improve resolution, particularly in the context of samples that are thin, or sensitive to beam exposure, or prone to charging upon exposure to a beam. Moreover, these advantages accrue without the complicated and / or demanding changes in the “column” of primary system components of the systems.

[0011] Disclosed herein are mechanisms and methods for combining Cs connection membranes and iDPC techniques in charged particle microscopy. In some embodiments, charged particle beam systems may comprise a source, a charged particle focusing column, a sample stage, and a segmented detector. The source may be operable to produce charged particles. The charged particle focusing column may be operable to form a focused beam of charged particles from charged particles produced by the source, and may include a Cs correction membrane arranged between the source and the focused beam of charged particles. The charged particle beam systems may also comprise one or more processors and non-transitory memory storing instructions which, when executed, cause the one or more processors to execute an algorithm. The algorithm may include acquiring a plurality of first images of a sample on the sample stage through the segmented detector, based upon an application of the focused beam of charged particles to the sample. The algorithm may also include producing one or more second images based upon the plurality of first images using an iDPC technique. The use of the Cs correction membrane in combination with the use of the iDPC technique may advantageously reduce a spherical aberration, and may thereby advantageously increase a resolution of the system, relative to the use of the iDPC technique alone. Similarly, the use of the iDPC technique in combination with the use of the Cs correction membrane may advantageously increase a contrast of the system and / or an SNR of the system relative to the use of the Cs correction membrane alone.BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1 is a schematic depiction of a Scanning Transmission Charged Particle Microscope (STCPM) system, in accordance with one or more embodiments;

[0013] FIG. 2 provides schematic depictions of various portions and embodiments of a Cs correction membrane for an STCPM system, in accordance with one or more embodiments;

[0014] FIG. 3 is a schematic depiction of various portions of an STCPM system including a Cs correction membrane and structures related to the use of integrated Differential Phase Contrast (iDPC) techniques, in accordance with one or more embodiments;

[0015] FIG. 4A and FIG. 4B include electron micrographs and corresponding fast Fourier transform (FFT) images of a first sample substance, in accordance with one or more embodiments;

[0016] FIG. 5A and FIG. 5B include electron micrographs and corresponding fast Fourier transform (FFT) images of a second sample substance, in accordance with one or more embodiments; and

[0017] FIG. 6 includes a flowchart of a method for using iDPC techniques in combination with a Cs correction membrane, in accordance with one or more embodimentsDETAILED DESCRIPTION

[0018] As discussed herein, charged particle microscopy systems, such as the system depicted in FIG. 1, may advantageously incorporate both a Cs correction membrane and structures related to the use of an iDPC technique. The Cs correction membrane portions depicted in FIG. 2 may alter a focus of a charged particle beam, which may then be incident upon a segmented detector as depicted in FIG. 3. FIG. 4A and FIG. 4B

[0019] FIG. 1 (not to scale) is a highly schematic depiction of an embodiment of a Scanning Transmission Charged Particle Microscope (STCPM) system M related to the mechanisms and methods disclosed herein. In some embodiments, STCPM system M may be a Transmission Electron Microscope (TEM), or a Scanning Transmission Electron Microscope (STEM). In various embodiments, STCPM system M may be an ion-based or proton microscope, for example, or any other charged particle microscope. In FIG. 1, within a vacuum enclosure 102, a charged particle source 104 (e.g., a Schottky emitter or an electron source) may produce a focused beam B of charged particles (e.g., electrons) that traverse a charged-particle-optical illuminator 106 (e.g., an electron -optical illuminator).

[0020] Illuminator 106 may serve to direct and / or focused beam B onto a chosen part of a specimen S (which may be a thinned and / or planarized specimen, such as a locally thinned and / or planarized specimen). Illuminator 106 may have a charged-particle-optical axis B', and may generally comprise a variety of components, which may include electrostatic lenses, magnetic lenses, one or more deflectors 108 (e.g., one or more scan deflectors), correctors (such as stigmators), and so on. In some embodiments, deflectors 108 may be used (inter alia) to effect a scanning motion of focused beam B. Illuminator 106 may also comprise a condenser system (sometimes, illuminator 106 may even be referred to as “a condenser system”).

[0021] In various embodiments, a Cs correction membrane may be arranged between charged particle source 104 and focused beam B. The Cs correction membrane may also be arranged between particle source 104 and one or more objective lenses of CTCPM system M. For example, the Cs correction membrane may be located upstream of one or more objective lenses of STCPM system M, and / or may be located somewhere within a condenser system of STCPM system M (e.g., within illuminator 106 or within a condenser system of illuminator 106). For various embodiments, the Cs correction membrane may be arranged in an aperture plate STCPM system M.

[0022] Specimen S may be held on a specimen holder H. Part of specimen holder H (e.g., a part inside enclosure 102) may be mounted in a cradle A' (and / or removably affixed into cradle A'). Specimen holder H may be positioned by a positioning device A (e.g., a sample stage) with multiple degrees of freedom (with reference to the depicted Cartesian coordinate system). For example, cradle A' may (inter alia) be displaceable in the X, Y and / or Z directions and / or may be rotated about a longitudinal axis parallel to X. In some embodiments, specimen holder H may comprise a finger that can be moved (inter alia) in the XY plane; typically, motion parallel to Z and tilt about X and / or Y may also be possible.

[0023] Such movements may enable different parts of specimen S to be irradiated, imaged, and / or inspected by the charged particle beam traveling along axis B' (e.g., in the Z direction). Such movements may also enable and / or facilitate a scanning motion to be performed as an alternative to beam scanning (e.g., using deflectors 108). In some embodiments, such movements may enable selected parts of specimen S to be machined (e.g., by a focused ion beam, not depicted herein). In various embodiments, an optional cooling device (not depicted herein) may be brought into intimate thermal contact with specimen holder H, so as to maintain specimen holder H, and specimen S thereupon, at cryogenic temperatures.

[0024] Focused beam B traveling along axis B' may interact with specimen S in such a manner as to cause various types of “stimulated” radiation to emanate from specimen S. Such radiation may include, for example, secondary electrons, backscattered electrons, X-rays, and / or optical radiation (e.g., cathodoluminescence). If desired, one or more of these radiation types can be detected with the aid of an analysis device 122, which might include a combined scintillator-and- photomultiplier, and / or an EDX (Energy-Dispersive X-Ray Spectroscopy) module, for instance.In such a case, an image could be constructed using operating principles substantially similar to those of a Scanning Electron Microscope (SEM).

[0025] However, alternatively or supplementally, a study may be made of electrons that traverse (e.g., pass through) specimen S, emerge (emanate) from it, and continue to propagate along axis B' (substantially, though generally with some deflection / scattering). Such a transmitted electron flux may enter an imaging system 124 (which may include an objective lens and / or a projection lens), which may generally comprise a variety of electrostatic lenses, magnetic lenses, deflectors, correctors (such as stigmators), and so on. In normal (non-scanning) TEM mode, imaging system 124 may focus a transmitted electron flux onto a fluorescent screen 126, which, if desired, can be retracted or withdrawn (as schematically indicated by arrows 126') so as to get it out of the way of axis B'. An image (or diffractogram) of specimen S (or part of specimen S) may be formed by imaging system 124 on screen 126, and this may be viewed through a viewing port 128 located in a suitable part of a wall of enclosure 102. The retraction mechanism for screen 126 (not depicted herein) may, for example, be mechanical and / or electrical in nature.

[0026] As an alternative to viewing an image on screen 126, one can instead make use of the depth of focus of the electron flux being generally quite large as it emerges from imaging system 124 (e.g. of the order of 1 meter). Consequently, various types of sensing device / analysis apparatus can be used downstream of screen 126, such as a TEM camera 130, a STEM detector 132, and / or a spectroscopic apparatus 134.

[0027] At TEM camera 130, the electron flux can form a static image (or diffractogram) that can be processed by one or more controllers 110 (e.g., one or more computer processors and / or other controllers, which are (schematically depicted herein) and displayed on a display device (not depicted herein), such as a flat panel display, for example. When not required, TEM camera 130 can be retracted or withdrawn (as schematically indicated by arrows 130') so as to get it out of the way of axis B'.

[0028] An output from STEM detector 132 can be recorded as a function of (X,Y) scanning position of focused beam B on specimen S, and an image can be constructed that is a “map” of output from STEM detector 132 as a function of X,Y. Typically, the acquisition rate of STEM detector 132 (e.g., 106 points per second) will be significantly higher than the acquisition rate of TEM camera 130 (e.g., 102 images per second). In conventional tools, STEM detector 132 can comprise a single pixel with a diameter of about 20 mm, for example, as opposed to the matrix ofpixels characteristically present in TEM camera 130. When not required, STEM detector 132 can be retracted or withdrawn (as schematically indicated by arrows 132') so as to get it out of the way of axis B'. However, such retraction might not be relevant in the case of a donut-shaped Annular Dark Field (ADF) detector associated with STEM detector 132, for example; in such a detector, a central hole may allow flux passage when the detector was not in use.

[0029] In the context of the concepts disclosed herein, STEM detector 132 may have a segmented structure. For example, STEM detector 132 may have a plurality of portions, such as (in various embodiments) four quadrants, or eight portions, or 48 portions, or any number of portions. The various portions of STEM detector 132 may be arranged in pairs whose members are symmetric with each other about a central axis of the segmented structure. In still further embodiments, the segmented detector may be a pixelated detector.

[0030] As an alternative to imaging using TEM camera 130 or STEM detector 132, one might also make use of spectroscopic apparatus 134 (which could include an Electron Energy Loss Spectroscopy (EELS) module, for example.

[0031] Moreover, in various embodiments, the order and / or location of TEM camera 130, STEM detector 132, and spectroscopic apparatus 134 may differ from the depiction, and various combinations thereof are conceivable. For example, in some embodiments, spectroscopic apparatus 134 might be integrated into imaging system 124.

[0032] The skilled artisan will understand that controllers 110 are connected to various illustrated components via control lines (buses) 110'. Controllers 110 can provide a variety of functions, such as synchronizing actions, providing setpoints, processing signals, performing calculations, and displaying messages / information on a display device (not depicted herein). In various embodiments, controllers 110 may be (partially) inside enclosure 102 or partially outside enclosure 102, and may have a unitary or composite structure, as desired.

[0033] FIG. 2 depicts a first Cs correction membrane 210, a second Cs correction membrane 220, and an enlarged portion of a Cs correction membrane 280. First Cs correction membrane 210 may have a multi-layer structure including a base layer 212, a middle layer 214 adjacent to base layer 212, and an outer layer 216 extending across middle layer 214. First Cs correction membrane 210 may also have an aperture region 218. Meanwhile, first Cs correction membrane 210 may itself be a relatively small central portion of a larger membrane sheet, in which the multi-layer structure extends significantly further from aperture region 218 than is depicted.

[0034] Similarly, second Cs correction membrane 220 may have a multi-layer structure including a base layer 222, a middle layer 224 adjacent to base layer 222, and an outer layer 226 extending across middle layer 224. First Cs correction membrane 220 may also have an aperture region 228. Meanwhile, first Cs correction membrane 220 may itself be a relatively small central portion of a larger membrane sheet, in which the multi-layer structure extends significantly further from aperture region 228 than is depicted.

[0035] In aperture region 218, base layer 212 has a substantially frustoconical cross-sectional shape. Middle layer 214 may have a substantially circular region extending across the aperture, and the substantially circular region may have an annular indentation positioned opposite aperture region 218 and extending into the material of middle layer 214.

[0036] Similarly, in aperture region 228, base layer 222 has a substantially frustoconical cross- sectional shape. Middle layer 224 may have a substantially circular region extending across the aperture, and the substantially circular region may have an annular indentation positioned opposite aperture region 228 and extending into the material of middle layer 224.

[0037] In various embodiments, base layer 212 and / or base layer 222 may be formed of materials including silicon, such as a portion of a silicon wafer. Middle layer 214 and / or middle layer 224 may be formed of materials including silicon nitride (Si3N4), and in some cases may be substantially formed from Si3N4. Meanwhile, outer layer 216 and / or outer layer 226 may be formed of materials including gold (Au), and in some cases may be substantially formed from Au. However, in various embodiments, other materials may be possible for the layers of these multilayered structures. For example, materials for which electrons scatter in a good ratio between being scattered elastically and being scattered non-elastically may be suitable in addition to and / or instead of Si3N4. Similarly, materials which have a high absorption may be suitable in addition to and / or instead of Au.

[0038] In various embodiments, middle layer 214 and / or middle layer 224 may be fabricated to include a layer of Si3N4 approximately 200 nanometer (nm) thick. For some embodiments, outer layer 216 and / or outer layer 226 may be fabricated to include a layer of Au approximately 150 nm thick.

[0039] Aperture region 218 and aperture region 228 may be approximately 100 microns in diameter. Outer layer 216 is depicted as having an aperture in aperture region 218 through which middle layer 214 is exposed. In comparison, outer layer 226 is depicted as not having an aperturethrough which middle layer 224 is exposed, but is instead depicted as extending across a surface of middle layer 224. In various embodiments, the Cs correction membranes disclosed herein may have a structure similar to either first Cs correction membrane 210 or second Cs correction membrane 220.

[0040] Enlarged portion of a Cs correction membrane 280 depicts the Si3N4 layer of the Cs correction membranes as having a relatively thick central portion and an annular region surrounding the relatively thick central portion.

[0041] Turning to FIG. 3, a schematic depiction shows the general relationship between a Cs correction membrane 310, an objective lens 320, a focused electron probe 330, a sample 340, an annular dark field (DF) detector 350, and a segmented detector 360. As depicted, charged particle beam paths (which may be substantially similar to beam B of SCTPM system M) may extend through Cs correction membrane 310, objective lens 320, focused electron probe 330, and sample 340, after which charged particles may be detected by annular DF detector 350 and / or by various segments of segmented detector 360.

[0042] The various segments of segmented detector 360 may themselves be located in pairs opposite a central region, e.g., in an axially symmetrical distribution. For example, a first segment 362 of a first pair of detector segments may be located opposite from a second segment 364 of the first pair of detector segments, and so on, for a plurality of pairs of segmented detector 360. In addition, tin various embodiments, he bright field (BF) disk may be slightly larger than the DF segmented detector, in order to further filter out electrons contributing to background signal.

[0043] FIG. 4A depicts a micrograph and an FFT image of a sample whose elemental composition includes strontium (Sr), titanium (Ti), and oxygen (O). FIG. 4A was obtained with the use of iDPC techniques, but without the use of a Cs correction membrane. In contrast, FIG. 4B depicts a micrograph and an FFT image of the sample obtained with both the use of iDPC techniques and the use of a Cs correction membrane. The smaller-diameter encapsulation of the bright regions in the FFT image of FIG. 4B indicates that the resolution is higher, as may also be seen in the micrographs themselves. In particular, individual atoms of O are clearly resolved in the micrograph of FIG. 4B, whereas they are not resolvable in the micrograph of FIG. 4A.

[0044] FIG. 5A depicts a micrograph and an FFT image of a sample whose elemental composition includes gallium nitride (GaN). FIG. 5 A was obtained with the use of High-Angle Annular Dark Field (HAADF) imaging, but without the use of a Cs correction membrane. In contrast, FIG. 5Bdepicts a micrograph and an FFT image of the sample obtained with both the use of iDPC techniques and the use of a Cs correction membrane. Again, the smaller-diameter encapsulation of the bright regions in the FFT image of FIG. 5B indicates that the resolution is higher, which may also be seen in the micrographs directly. For example, there is a higher contrast among the rows of atoms in FIG. 5B than among the rows of atoms in FIG. 5A.

[0045] Based on FIG. 4A, FIG. 4B, FIG. 5A, and FIG. 5B, the combination of a Cs correction membrane and the use of iDPC techniques may improve resolution from about 1.4 A to about 1.0 A. The combined use of a Cs correction membrane and iDPC techniques may advantageously reduce noise that might otherwise obstruct real use cases.

[0046] In FIG. 6, a method 600 for improving charged particle beam imaging may comprise a forming 610, an acquiring 620, and a producing 630. In various embodiments, method 600 may also comprise a combining 640, a compiling 650, and / or a performing 660. In forming 610, a focused beam of charged particles may be formed through a spherical aberration (Cs) correction membrane. In acquiring 620, a plurality of first images of a sample on a sample stage through a segmented detector, based upon an application of the focused beam of charged particles to the sample. In producing 630, one or more second images may be produced based upon the plurality of first images using an integrated differential phase contrast (iDPC) technique.

[0047] In some embodiments, the Cs correction membrane may be arranged in an aperture plate of a charged particle focusing column. For some embodiments, the Cs correction membrane may be arranged between charged particles produced by a source and an objective lens of a charged particle focusing column.

[0048] In various embodiments, the Cs correction membrane may have a multi-layer structure including a base layer, a middle layer adjacent to the base layer, and an outer layer extending across the middle layer. For some embodiments, the base layer may have an aperture with a substantially frustoconical cross-sectional shape, and / or the middle layer may have a substantially circular region extending across the aperture. The substantially circular region may have an annular indentation opposite the aperture.

[0049] In some embodiments, the middle layer may be substantially formed from silicon nitride (Si3N4) and the outer layer is substantially formed from gold (Au).

[0050] For some embodiments, in combining 640, the plurality of first images may be combined to produce a vector output from the segmented detector at each of a plurality of scan positions. In some embodiments, in compiling 650, the vector outputs may be compiled to yield an imaging vector field. The plurality of first images may include signal information from different segments of the segmented detector.

[0051] In some embodiments, in performing 650, a two-dimensional integration operation may be performed on the imaging vector field to produce the one or more second images. The one or more second images may include an integrated vector field image of the specimen.

[0052] For some embodiments, the segmented detector may include a plurality of quadrants positioned in opposing pairs across a center of the segmented detector. In some embodiments, the segmented detector includes at least one of a 4-quadrant detector, an 8-quadrant detector, a 48- segment detector, and a pixelated detector.

[0053] In various embodiments, method 600 may be carried out by one or more processors (such as the controllers and / or processors of FIG. 1) and instructions stored in a memory which, when executed, cause various portions of the algorithm of method 600 to be carried out.INCORPORATION BY REFERENCE

[0054] All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.

[0055] The following documents are specifically and individually indicated to be incorporated by reference in their entirety:

[0056] US Patent No. 10,699,872 (serial code / serial number 16 / 288,305; U.S. Patent Application Publication No. 2019 / 0272974)

Claims

CLAIMS1. A charged particle beam system, comprising: a source operable to produce charged particles; a charged particle focusing column operable to form a focused beam of charged particles from charged particles produced by the source, the charged particle focusing column including a spherical aberration (Cs) correction membrane arranged between the source and the focused beam of charged particles; a sample stage; a segmented detector: one or more processors; and a non-transitory memory storing instructions which, when executed, cause the one or more processors to: acquire a plurality of first images of a sample on the sample stage through the segmented detector, based upon an application of the focused beam of charged particles to the sample; and produce one or more second images based upon the plurality of first images using an integrated differential phase contrast (iDPC) technique.

2. Tire system of claim 1, wherein the Cs correction membrane is arranged in an aperture plate of the charged particle focusing column.

3. The system of claim 1, wherein the Cs correction membrane is arranged between charged particles produced by the source and an objective lens of the charged particle focusing column.

4. The system of claim 1, wherein the Cs correction membrane has a multi-layer structure including a base layer, a middle layer adjacent to the base layer, and an outer layer extending across the middle layer.

5. Tire system of claim 4, wherein the base layer has an aperture with a substantially frustoconical cross-sectional shape; and wherein the middle layer has a substantially circular region extending across the aperture, the substantially circular region having an annular indentation opposite the aperture.

6. The system of claim 4, wherein the middle layer is substantially formed from silicon nitride (Si3N4) and the outer layer is substantially formed from gold (Au).

7. The system of claim 1, wherein the iDPC technique includes: combining the plurality of first images to produce a vector output from the segmented detector at each of a plurality of scan positions, and compiling the vector outputs to yield an imaging vector field; wherein the plurality of first images include signal information from different segments of the segmented detector.

8. The system of claim 7, wherein the iDPC technique includes: perfonning a two-dimensional integration operation on the imaging vector field to produce the one or more second images, wherein the one or more second images include an integrated vector field image of the specimen.

9. The system of claim 1, wherein the segmented detector includes a plurality of quadrants positioned in opposing pairs across a center of the segmented detector.

10. The system of claim 1, wherein the segmented detector includes at least one of a 4-quadrant detector, an 8-quadrant detector, a 48-segment detector, and a pixelated detector.

11. A method for improving charged particle beam imaging, comprising: forming a focused beam of charged particles through a spherical aberration (Cs) correction membrane; acquiring a plurality of first images of a sample on a sample stage through a segmented detector, based upon an application of the focused beam of charged particles to the sample; and producing one or more second images based upon the plurality of first images using an integrated differential phase contrast (iDPC) technique.

12. The method of claim 11, wherein the Cs correction membrane is arranged in an aperture plate of a charged particle focusing column.

13. The method of claim 11, wherein the Cs correction membrane is arranged between charged particles produced by a source and an objective lens of a charged particle focusing column.

14. Tire method of claim 11, wherein the Cs correction membrane has a multi-layer structure including a base layer, a middle layer adjacent to the base layer, and an outer layer extending across the middle layer.

15. The method of claim 14, wherein the base layer has an aperture with a substantially frustoconical cross-sectional shape; and wherein the middle layer has a substantially circular region extending across tire aperture, the substantially circular region having an annular indentation opposite the aperture.

16. The method of claim 14, wherein the middle layer is substantially formed from silicon nitride (Si3N4) and the outer layer is substantially formed from gold (Au).

17. The method of claim 11, wherein the iDPC technique includes: combining the plurality of first images to produce a vector output from the segmented detector at each of a plurality of scan positions, and compiling the vector outputs to yield an imaging vector field; wherein the plurality of first images include signal information from different segments of the segmented detector.

18. The method of claim 17, wherein the iDPC technique includes:performing a two-dimensional integration operation on the imaging vector field to produce the one or more second images, wherein the one or more second images include an integrated vector field image of the specimen.

19. The method of claim 11, wherein the segmented detector includes a plurality of quadrants positioned in opposing pairs across a center of the segmented detector.

20. Tire method of claim 11, wherein the segmented detector includes at least one of a 4-quadrant detector, an 8-quadrant detector, a 48-segment detector, and a pixelated detector.

Images