Method and system for checking orientation of sample using charged particle microscopy

Abstract

In some embodiments, a scientific instrument includes a manipulator configured to controllably rotate a sample, an electron beam column configured to direct an electron beam to a selected point of impact on the sample; and a detector configurable to detect the angular resolution pattern and the flux of the backscattered electrons. The scientific instrument also includes an electronic controller configured to: determine a first crystal orientation of the sample based on an angularly resolved pattern acquired while operating the electron beam column to maintain the electron beam fixed at an impact point; operating the manipulator to place the sample in a second crystal orientation in which an angular difference between the determined first crystal orientation and the target crystal orientation is estimated to be cancelled; and determining a second crystal orientation based on the acquired SACP when operating the electron beam column to oscillate the electron beam at the point of impact.

Description

Technical Field

[0001] Various examples relate generally, but not exclusively, to charged particle microscopy components, instruments, systems, and methods. Summary of the invention

[0002] One example provides a scientific instrument comprising: a manipulator configured to controllably rotate a sample about a first rotation axis and about a second rotation axis oriented at a non-zero angle relative to the first rotation axis; an electron beam column configured to direct an electron beam to a selected impact point on the sample; one or more detectors configurable to detect an angularly resolved pattern of backscattered electrons emitted from the selected impact point in response to the electron beam and further configurable to detect a flux of backscattered electrons emitted from the selected impact point in response to the electron beam; and an electronic controller configured to: when operating the electron beam, The method further comprises operating a beam column to determine a first crystal orientation of a region of interest (ROI) within a sample based on an angularly resolved pattern of backscattered electrons collected using one or more detectors while maintaining the electron beam at a first impact point within the ROI; operating a manipulator to place the ROI into a second crystal orientation in which an angular difference between the determined first crystal orientation and a target crystal orientation is estimated to be substantially eliminated; and determining a second crystal orientation based on a first selected area electron channeling pattern (SACP) collected using one or more detectors while operating the scientific instrument to cause the electron beam to oscillate relative to the sample at a second impact point within the ROI.

[0003] In some examples, one or more detectors are implemented using a single movable pixelated BSE detector.

[0004] In some other examples, one or more detectors include a first BSE detector that is configurable to detect an angularly resolved pattern of backscattered electrons emitted from a selected impact point in response to the electron beam; and a different second BSE detector that is configurable to detect a flux of backscattered electrons emitted from the selected impact point in response to the electron beam.

[0005] Another example provides an automated method, which includes: when operating an electron beam column to direct the electron beam to a first impact point within a region of interest (ROI) of a sample held by a sample holder, using one or more detectors to collect an electron backscatter diffraction pattern (EBSD); determining a first crystal orientation of the ROI based on the collected EBSD; operating a manipulator coupled to the sample holder to place the ROI in a second crystal orientation so as to substantially eliminate the angular difference between the determined first crystal orientation and the target crystal orientation; when operating the electron beam so that the electron beam swings at a second impact point within the ROI, using one or more detectors to collect a first selected area electron channeling pattern (SACP) of the ROI placed in the second crystal orientation; and determining the second crystal orientation based on the collected first SACP.

[0006] Yet another example provides a non-transitory computer-readable medium storing instructions that, when executed by a computing device, cause the computing device to perform operations including the automated method described above.

[0007] Yet another example provides a scientific instrument comprising: an electron beam column configured to direct an electron beam to a sample; a manipulator configured to adjust the orientation of the sample relative to the electron beam; one or more detectors for detecting backscattered electrons from the sample; and an electronic controller comprising a processor and a memory for storing program code, wherein the memory and the program code are configured to cause the scientific instrument to perform at least the following operations using the processor: direct the electron beam toward an ROI of the sample and collect at least one EBSD pattern using one or more detectors; adjust the orientation of the sample toward a target crystal orientation via the manipulator based on the EBSD; direct the electron beam toward the ROI and collect a first SACP using one or more detectors; and adjust the orientation of the sample toward a target crystal orientation via the manipulator based on the first SACP.

[0008] Yet another example provides a scientific instrument comprising: an electron beam column configured to direct an electron beam to a sample; a manipulator configured to adjust an orientation of the sample relative to the electron beam; one or more detectors for detecting backscattered electrons from the sample; and an electronic controller comprising a processor and a memory for storing program code, wherein the memory and the program code are configured to cause the scientific instrument to perform at least the following operations using the processor: direct the electron beam toward an ROI of the sample and collect at least one EBSD pattern using one or more detectors; adjust the orientation of the sample toward a target crystal orientation via the manipulator based on the EBSD; direct the electron beam toward the ROI and collect an electron channel pattern (ECP) using one or more detectors; and adjust the orientation of the sample toward a target crystal orientation via the manipulator based on the ECP.

[0009] Yet another example provides a scientific instrument comprising: an electron beam column configured to direct an electron beam to a sample; a manipulator configured to adjust an orientation of the sample relative to the electron beam; one or more detectors for detecting backscattered electrons from the sample; and an electronic controller comprising a processor and a memory for storing program code, wherein the memory and the program code are configured to cause the scientific instrument to perform at least the following operations using the processor: direct the electron beam toward a region of interest (ROI) of the sample, and collect at least one electron backscatter diffraction (EBSD) pattern using one or more detectors; adjust the orientation of the sample toward a target crystal orientation via the manipulator based on the EBSD; direct the electron beam toward the ROI, and collect a first selected area electron channeling pattern (SACP) using one or more detectors; and adjust the orientation of the sample toward a target crystal orientation via the manipulator based on the first SACP. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The foregoing aspects and many of the attendant advantages of the present disclosure will become more readily appreciated when the following detailed description is taken in conjunction with the accompanying drawings, wherein:

[0011] Figure 1 is a block diagram illustrating an example scientific instrument according to some embodiments.

[0012] Figure 2 is a block diagram illustrating a scientific instrument according to another example.

[0013] Figure 3 is a diagram showing the use of an example Figure 2 Block diagram of the detector configuration for acquiring 2D electron diffraction patterns.

[0014] Figure 4 Showing the use according to an example Figure 3 The acquisition process captures the electron diffraction pattern.

[0015] Figure 5 is a diagram showing the use of an example Figure 2 Block diagram of the detector configuration for SACP measurement.

[0016] Figure 6 shows the use according to an example Figure 5 The acquisition process captures the SACP.

[0017] Figure 7 is a diagram showing the available Figure 1 Flowchart of the automated method for lattice defect imaging implemented in scientific instruments.

[0018] Figure 8 shows the use according to an example Figure 7 SEM images collected by the method.

[0019] Fig. 9 is a block diagram of an example computing device configured to perform at least some scientific instrument support operations, according to various embodiments. DETAILED DESCRIPTION

[0020] Accurately determining the crystal orientation of a sample is a key prerequisite for high-quality imaging and / or processing of a sample using a charged particle microscope. Based on the determined crystal orientation, the sample can be oriented so that the charged particle beam is aligned with the crystal structure of the sample. For example, in order to perform electron channel contrast imaging (ECCI), the sample must be placed under electron channel conditions based on its crystal orientation. In another example, the atomic plane of the sample can be selected based on the crystal orientation, and a thin slice can be extracted by cutting along the selected atomic plane to further examine in a transmission electron microscopy (TEM) system. The applicant recognizes that electron backscatter diffraction (EBSD) patterns, electron channel patterns (ECPs), and selected area electron channel patterns (SACPs) can all determine crystal orientation. EBSD is formed by collecting angle-resolved backscattered electrons emitted from the impact point in response to the electron beam irradiating the impact point. ECP and SACP are formed by collecting backscattered electrons that vary with respect to the incident direction of the electron beam about the crystal structure of the sample. ECP can be acquired by scanning a relatively large sample area, and SACP can be acquired by swinging the electron beam and / or the sample while directing the electron beam to essentially one impact point or a small sample area. Crystal orientation estimates based on ECP and SACP have higher angular resolution and accuracy than EBSD. However, since ECP and SACP examine a smaller angular range than EBSD. ECP or SACP may not uniquely determine the crystal orientation because both methods only identify a small part of the reciprocal space. In order to obtain complete information, especially about polycrystalline materials, one needs the context provided by the EBSD method.

[0021] To address the above issues, the sample is first oriented based on EBSD, and then oriented based on ECP or SACP. In some examples, an initial rough alignment of the sample under test (SUT) to the Bragg condition of a selected set of lattice planes is performed with a lower angular accuracy (e.g., about 1 degree) based on the electron backscatter diffraction (EBSD) pattern. Then, based on one or more selected area SACPs obtained after the sample is oriented based on EBSD, the initial rough alignment is refined to a higher angular accuracy (e.g., better than about one tenth of a degree). By performing ECP / SACP after orienting the sample based on EBSD, the crystal orientation of the sample can be estimated more quickly and accurately than based on either EBSD or SACP. In some examples, the crystal orientation can be determined based on ECP or SACP. However, for certain types of samples, such as polycrystalline samples, SACP is preferred because it can be collected by examining a smaller sample area than ECP.

[0022] In some examples, EBSD is collected with a retractable two-dimensional (2D) pixelated BSE detector. SACP is collected with an annular BSD detector, which can also be used for scanning electron microscopy (SEM) imaging. SACP can be collected after retracting the 2D pixelated BSE detector. During and between EBSD collection and SACP collection, the sample remains on the sample holder. The sample orientation is adjusted by a manipulator coupled to the sample holder. The electronic controller applies a suitable processing algorithm to determine the adjustment of the two rotation angles of the SUT and operates the sample manipulator to perform the corresponding rotation. In some examples, instead of orienting the sample about 70 degrees relative to the incident electron beam, EBSD is collected by positioning the 2D pixelated BSE detector between the pole piece of the electron column and the sample. The 2D pixelated BSE detector can be positioned substantially perpendicular to the beam axis of the electron column.

[0023] In some examples, once the SUT is oriented under dual-beam diffraction conditions based on SACP, the electron beam column and annular BSE detector can be switched to SEM imaging mode to perform (Electron Channeling Contrast Imaging) ECCI. Advantageously, the acquired SEM images have optimal contrast for clearly visualizing the various lattice defects present in the SUT.

[0024] ECCI is a scanning electron microscopy (SEM) technique that exploits the strong dependence of the backscattered electron (BSE) signal on the orientation of the lattice planes relative to the incident electron beam due to the electron channeling mechanism. Local deformations in the lattice generated by the strain fields associated with certain lattice defects (such as dislocations, grain boundaries, stacking faults, point defects and deformation twins) typically impose modulations on the BSE signal that can be detected with a suitable BSE detector. As a result, the corresponding lattice defects can be visualized in the SEM image.

[0025] According to the kinetic theory of electron diffraction, the best contrast for imaging lattice defects via ECCI is obtained when the crystal sample under test is oriented substantially exactly in Bragg conditions for a selected set of lattice planes (i.e., in electron channeling conditions or two-beam diffraction conditions). Even small deviations from exact orientation can result in a significant reduction in ECCI contrast, and for defect characterization and metrology, sample orientation is typically required to have an accuracy of about 0.1°. Therefore, a fast and accurate method for properly orienting the SUT in a SEM instrument is very important for a variety of ECCI applications.

[0026] Figure 1 1 is a block diagram illustrating a scientific instrument 100 according to some embodiments. The scientific instrument 100 includes a SEM column 102 coupled to a vacuum chamber 108. The vacuum chamber 108 houses a movable sample holder 110 therein and can be vacuumed using one or more vacuum pumps (in Figure 1 The sample S to be interrogated using the scientific instrument 100 is mounted in the sample holder 110, as shown in FIG. Figure 1 shown.

[0027] In some embodiments, the sample holder 110 is capable of independent movement parallel to the XY coordinate plane and parallel to the Z coordinate axis, where the corresponding coordinate system is represented by Figure 1 Indicated by the XYZ coordinate triplet shown in . In some embodiments, the sample holder 110 can be rotated, translated, or non-translated relative to the XYZ coordinate system. In some examples, the sample holder 110 includes a goniometer that can independently rotate at least about mutually orthogonal eccentric (eucentric) tilt axis and azimuth rotation axis. In other examples, the goniometer can achieve rotation around other suitable types of non-parallel rotation axes. The electronic controller 150 is operative to generate a control signal 158, in response to which the sample holder 110 translates and / or rotates the sample S by a specified amount. An example sample holder suitable for rotating a sample S and adjusting the position of the sample relative to the electron beam is disclosed in U.S. Patent No. 10,784,076, which is incorporated herein by reference in its entirety.

[0028] In the example shown, the SEM column 102 includes an electron source 112 and two or more electron beam lenses, which are shown for illustration purposes only. Figure 1 Only two of them are schematically shown, namely the objective lens 106 and the condenser lens 116. In some examples, a different (other than two) number of such lenses may be used in the SEM column 102. In some embodiments, the objective lens 106 may be an ultra-high resolution (UHR) lens.

[0029] In operation, the electron source 112 generates an electron beam 114 that propagates generally along a longitudinal axis 115 of the SEM column 102. The electron beam lenses 106 and 116 operate to generate electric and magnetic fields that affect the trajectories of electrons in the electron beam 114. The scientific instrument 100 includes an electronic controller 150. The electronic controller 150 may include a processor (e.g., Fig. 9 902 in ) and a memory for storing computer-readable instructions (e.g., Fig. 9904 in). In various examples, the electronic controller 150 implements at least some of the methods disclosed herein by executing computer-readable instructions stored in a memory. For example, the control signals 152, 156 generated by the electronic controller 150 are used to change the intensity and / or spatial configuration of the field and impart desired characteristics to the electron beam 114. In general, the electron beam lenses 106 and 116, the control signals 152 and 156, and other related components of the scientific instrument 100 can be used to perform various operations and support various functions, such as beam focusing, aberration mitigation, aperture clipping, filtering, etc. The SEM column 102 also includes a deflection unit 118, which can guide the electron beam 114 in response to the control signal 154 applied thereto by the electronic controller 150. Such beam steering can be used, for example, to move a focused portion of the electron beam 114 along a desired path across the sample S to perform a raster or vector scan thereof and / or to change the angle of incidence of the electron beam 114 at the sample S.

[0030] The scientific instrument 100 also includes detectors 160, 170, 180 located in the vacuum chamber 108 relatively close to the sample S. In operation, the detectors 160, 170, and 180 generate measurement streams 162, 172, and 182 received by the electronic controller 150. The specific type of detectors 160, 170, 180 depends on the embodiment of the scientific instrument 100, and can generally be selected from a variety of detector types suitable for detecting different types of emissions and / or radiation from the sample S generated in response to the electron beam 114. Example types of emissions / radiation that can be generated in this manner include, but are not limited to, X-rays, infrared light, visible light, ultraviolet light, backscattered electrons, secondary electrons, Auger electrons, elastically scattered electrons, non-scattered (e.g., zero energy loss) electrons, and inelastically scattered electrons. In various embodiments, different (other than three) numbers of such detectors can be used in the scientific instrument 100. In some embodiments, some or all of the detectors 160, 170, 180 are retractable and / or replaceable without balancing the vacuum chamber 108 to atmospheric pressure or opening the vacuum chamber 108. In some embodiments, the detectors 160, 170, 180 are selected from the group consisting of an annular detector, a segmented annular detector, a differential phase contrast detector, a two-dimensional (e.g., pixelated or segmented) diffraction pattern detector, a BSE detector, an electron backscatter diffraction (EBSD) detector, and a forward scattered electron (FSE) detector. Other detectors capable of detecting various of the above-mentioned types of emission / radiation may also be used in various additional embodiments.

[0031] Figure 2 2 is a block diagram showing a scientific instrument 200 according to another example. The scientific instrument 200 includes some of the same elements as the scientific instrument 100, which are connected to the Figure 1The scientific instrument 200 includes one or more BSE detectors, such as one or both of the detectors 210 and 220, which are used to detect when the electron beam 114 (see also Figure 1 ) when it strikes the sample S, and is also configured to communicate corresponding detected BSE signals 212, 222 to the electronic controller 150. In one example, the BSE detector 210 is a retractable detector for collecting EBSD patterns. The BSE detector 220 is a ring detector for collecting SACP. In various examples, the BSE detector 220 is a fixed detector or a retractable detector. When the BSE detector 210 is deployed and in Figure 2 , the BSE detector 220 is idle (e.g., not performing measurements) when the BSE detector 210 is in the position indicated in . When the BSE detector 210 is retracted from the position shown, the BSE detector 220 can be activated to perform BSE measurements. When used, the BSE detector 220 can perform SACP measurements or SEM image acquisition at different corresponding times and in different corresponding operating modes of the scientific instrument 100. In various examples, such different operating modes employ similar probe geometries that substantially maintain the relevant geometric relationship between the electron beam 114 and the sample S.

[0032] In the example shown, the BSE detectors 210 and 220 both have respective openings 208, 218 aligned with the longitudinal axis 115 of the SEM column 102 to allow the electron beam 114 to pass through and impinge on the sample S. The scientific instrument 200 includes an automatic manipulator 206 having five degrees of freedom, including X, Y, and Z translations and R1 and R2 rotations. In some examples, the manipulator 206 includes a sample holder 110. In some other examples, the sample holder 110 is coupled to the manipulator 206 in a manner consistent with the desired translation and / or rotation of the sample S. In some examples, the movement corresponding to the various degrees of freedom of the manipulator 206 is controlled by the electronic controller 150 via the control signal 158, as described above.

[0033] In some embodiments, instead of the two BSE detectors 210 and 220 shown, the detector configuration 200 may employ a more general purpose single BSE detector designed and configured to perform several types of BSE measurements, including utilizing Figure 2BSE measurements performed by the BSE detectors 210 and 220 in the illustrated embodiment. In some examples, such a single BSE detector is a movable 2D pixelated BSE detector characterized by a relatively fast readout time. In some examples, measurements that are functionally corresponding to the measurements performed with the illustrated BSE detectors 210 and 220 are performed using different corresponding pixel binning configurations and / or positions of such a single BSE detector. For purposes of illustration and without any implied limitation, an example embodiment is described below with reference to a detector configuration 200 employing the illustrated BSE detectors 210 and 220. Based on the description provided, one of ordinary skill in the relevant art will readily understand how to make and use corresponding embodiments employing a single movable 2D pixelated BSE detector without any undue experimentation.

[0034] Figure 3 is a block diagram illustrating the acquisition of electron diffraction patterns using the BSE detector 210 according to one example. In the example shown, the electron beam 114 irradiates the sample S by propagating to the sample S along an irradiation axis 304. The electron beam 114 strikes the sample S at an impact point 306 within a region of interest (ROI) 308 on the sample surface. The impact point 306 includes a volume of the sample S that interacts with the beam 114. In one example, a normal 302 to the top surface of the sample S is oriented at an oblique angle θ relative to the irradiation axis 304, which remains fixed during EBSD signal acquisition. Such an EBSD pattern may be obtained using Figure 1 Scientific instruments 100 or Figure 2 The scientific instrument 200 is used to collect. In another example, the sample S is not tilted relative to the illumination axis 304. In such an example, the normal 302 of the sample surface and the illumination axis 304 are collinear. That is, the tilt angle θ is θ=0. As a result, the 2D pixel array of the retractable detector 210 is oriented parallel to the top surface of the sample S and perpendicular to the illumination axis 304. When the impact point 306 is irradiated by the electron beam 114, the backscattered electrons 314 emitted from the impact point 306 are detected in an angle-resolved manner by the corresponding BSE detector (e.g., the 2D pixel array of the BSE detector 210). The values ​​of the signals accumulated by the individual pixels of the pixel array during the illumination interval (dwell time) are read out therefrom and sent to the electronic controller 150 via the corresponding output signal 212.

[0035] Figure 4 shows the use according to an example Figure 2EBSD pattern 400 captured by the acquisition setup of . In the example shown, sample S is an electropolished tungsten specimen. EBSD pattern 400 has multiple sets of parallel line pairs, commonly referred to as Kikuchi line pairs (or bands). The spacing and configuration of the pairs correspond to specific crystal structures and orientations. The places where different Kikuchi line pairs in the EBSD pattern 400 intersect are called zone axes. The angles between the lines connecting the different zone axes indicate the crystal structure of sample S. These and other features of the EBSD pattern 400 can be quantified using a suitable EBSD pattern processing algorithm. Based on this quantification, the crystal orientation of sample S at the impact point 306 relative to the irradiation axis 304 can be determined. The typical accuracy of determining the crystal orientation based on an EBSD pattern such as EBSD pattern 400 is about 1 degree to 2 degrees.

[0036] In one example, the crystal orientation is determined by matching the EBSD pattern 400 with one of the known EBSD patterns (or a computer-simulated version thereof). In another example, the crystal orientation is calculated by comparing the measured angles between the Kikuchi bands with the theoretical interplanar angles determined using standard crystallographic principles. Several other EBSD pattern processing algorithms suitable for crystal orientation determination are reviewed, such as those discussed in TBBritton, J. Jiang, Y. Guo, et al., “Tutorial: Crystal orientations and EBSD—Or which way is up?”, Materials Characterization, 2016, v. 117, pp. 113-126, which is incorporated herein by reference in its entirety.

[0037] Figure 5 is a block diagram illustrating SACP measurement using the ring BSE detector 220 according to one example. Note that Figure 5 The detector configuration shown can be Figure 2 The SACP mode of the scientific instrument 200 shown in FIG. 2 is obtained, wherein the BSE detector 210 is obtained from Figure 2 The SEM column 102 is retracted to the indicated position. To acquire the SACP, the SEM column 102 is operated to direct the electron beam 114 to the impact point 506 on the surface of the sample S, and the angle of incidence of the electron beam 114 is changed in a process generally referred to as beam swaying. The angle of incidence of the electron beam can be adjusted by adjusting the electron column to change the direction of the electron beam relative to the beam axis and / or adjusting the manipulator to change the orientation of the sample relative to the beam axis. An example SEM column configuration that can be used for beam swaying is disclosed, for example, in U.S. Patent No. 9,093,246, which is incorporated herein by reference in its entirety.

[0038] In operation, the incident angle of the electron beam 114 is varied by the SEM column 102, for example, to sample different incident angles within the cone 510. In some examples, the cone 510 is a circular or elliptical cone having a vertex angle in a range between about 0.05 degrees and about 15 degrees. In some related literature, the vertex angle is also referred to as a "convergence" angle. In some examples, the convergence angle is about 0.5 degrees. As an example, in Figure 5 Two different incident angles corresponding to electron beam propagation directions 502 and 504 are shown in FIG. At different incident angles within cone 510, BSE detector 220 is operated to capture and measure corresponding BSE signals. Figure 5 2, labeled 512 and 514. BSE signal 512 is generated when electron beam 114 strikes impact point 506 from propagation direction 502. BSE signal 514 is similarly generated when electron beam 114 strikes impact point 506 from propagation direction 504. Values ​​of the BSE signals corresponding to different electron beam propagation directions captured by BSE detector 220 during corresponding time intervals are read therefrom and sent to electronic controller 150 via output signal 222.

[0039] Figure 6 shows the use according to an example Figure 5 600 captured by the acquisition setup of the SACP. In the example shown, the sample S is a silicon-germanium layer on a silicon wafer. By analyzing the position of the contrast / intensity lines therein, fine details of the crystal structure, including crystal orientation and local lattice parameters, can be obtained from the SACP. In one example, the crystal orientation is determined from the SACP using a dictionary-based algorithm. The dictionary indexing of the SACP can be accomplished, for example, by simulating a pattern of all possible Euler angle combinations, with some finite step sizes in the orientation space. The algorithm run by the electronic controller 150 then operates to determine the best fit to the experimental SACP. The typical accuracy of determining the crystal orientation from a SACP such as the SACP 600 via a dictionary-based algorithm is about 0.1 degrees. In various additional embodiments, other methods of determining the crystal orientation from the SACP that are suitable for determining the crystal orientation from the SACP can also be applied to the SACP 600 to determine the crystal orientation of the sample S at the impact point 506.

[0040] In some examples, instead of rocking the electron beam, the sample can be rocked to achieve various incident beam angles. In other examples, SACP can be acquired by combining beam and sample rocking. In other examples, SACP can be formed from data acquired from different impact points, where the different impact points belong to the same grain (or have the same crystal orientation).

[0041] Figure 7is a flow chart illustrating an automated method 700 for imaging lattice defects using scientific instrument 100 or 200 according to some embodiments. Figures 1 to 6 700. It should also be noted that the method 700 uses three different modalities of scientific instrumentation, namely EBSD, SACP and SEM imaging modalities, as described in more detail below.

[0042] Method 700 includes configuring scientific instrument 100 or 200 to operate in EBSD mode (in block 702). This configuration mode may include positioning retractable detector 210 above a sample, such as Figure 2 The operations of block 702 also include the electronic controller 150 activating the retractable detector 210 and deactivating the detector 220 (if previously activated). In some examples, the operations of block 702 may also include tilting the sample S relative to the electron beam and acquiring a preliminary EBSD pattern using an EBSD detector.

[0043] The method 700 also includes the electronic controller 150 acquiring an EBSD pattern of the sample S (in block 704). An example EBSD pattern that may be acquired in block 704 is Figure 4 400 of the EBSD pattern. The operation of block 704 includes the electronic controller 150 operating the SEM column 102 and the detector 210 to capture at least one EBSD pattern of a region of interest (ROI) of the sample S. The operation of block 704 also includes the electronic controller 150 receiving an image frame containing the captured EBSD pattern from the detector 210 via its output signal 212. In some examples, the ROI is a selected grain in the polycrystalline sample S. The grain of interest can be identified and / or selected based on, for example, a SEM scan of the sample S performed prior to the above-described operation of block 702. In some other examples, the ROI is a selected portion of the single crystal sample S.

[0044] The method 700 also includes the electronic controller 150 determining the crystal orientation of the ROI based on the acquired EBSD (in block 706). Here, the crystal orientation can be determined relative to the electron beam. The operation of block 706 includes the electronic controller 150 applying the EBSD pattern processing algorithm to the image frame received in block 704, for example, as described above with reference to Figure 4 As already noted above, typical EBSD pattern processing algorithms produce the crystal orientation of the ROI with an accuracy of approximately 1 to 2 degrees.

[0045] The method 700 also includes the electronic controller 150 selecting a diffraction condition (in box 708). The diffraction condition corresponds to a target crystal orientation of the ROI relative to the electron beam. For example, when placed in the target crystal orientation, the ROI satisfies the electron channeling condition. In some examples, the diffraction condition is selected based on the crystal orientation determined in 706. In some examples, the diffraction condition is selected in box 708 based on input from an operator. In some other examples, the diffraction condition is selected in box 708 based on pre-programmed criteria that reflect the purpose of the SEM imaging performed in a subsequent SEM imaging mode. In some cases, the diffraction condition is selected based on other indicia of defect type, spatial group, and target orientation of the ROI.

[0046] The method 700 also includes changing the orientation of the sample S (in box 710). The operation of box 710 includes the electronic controller 150 calculating an estimated first rotation angle (R1) and an estimated second rotation angle (R2) by which the sample manipulator of the sample holder 110 needs to rotate the sample S so that the crystal orientation of the ROI changes from the crystal orientation determined in box 706 to a crystal orientation corresponding to the diffraction condition selected in box 708. The operation of box 710 also includes the electronic controller 150 generating appropriate control signals 158 for the sample manipulator of the sample holder 110 to perform the R1 and R2 rotations by the calculated first rotation angle and the second rotation angle. In some examples, the generated control signals 158 may also include instructions for selecting an X, Y and / or Z translation so that the impact point 506 for a subsequent SACP mode can be placed into the same ROI. In some examples, the translation is selected so that the impact point 506 can substantially overlap with the impact point 306 for the operation of box 704 (see also). Figure 3 and Figure 5 ).

[0047] The method 700 also includes configuring the scientific instrument 100 or 200 to operate in the SACP mode (in block 712). Such configuration may include adjusting and / or retracting the BSE detector. In one example of block 712, retracting Figure 2 The detector 210 shown in FIG. Figure 5 The operations of block 712 also include the electronic controller 150 activating the detector 220 .

[0048] The method 700 also includes the electronic controller 150 acquiring the SACP of the sample S (in block 714). An example SACP that may be acquired in block 714 is Figure 6The operation of block 714 includes the electronic controller 150 operating the SEM column 102 to swing the electron beam 114 at the impact point 506, and operating the BSE detector 220 (e.g., as described above with reference to Figure 5 ) to capture the SACP for the ROI of the sample S. In a representative example, the impact point 306 corresponding to block 704 and the impact point 506 corresponding to block 714 are located in the same die. In some examples, the impact point 306 corresponding to block 704 and the impact point 506 corresponding to block 714 may coincide or overlap. The operation of block 704 also includes the electronic controller 150 receiving a measurement stream representing the captured SACP from the BSE detector 220 via the signal 222.

[0049] The method 700 also includes the electronic controller 150 determining the crystal orientation of the ROI (in block 716). The operation of block 716 includes the electronic controller 150 applying a suitable SACP processing algorithm to the SACP received in block 714, for example, as described above with reference to Figure 6 As already noted above, typical SACP processing algorithms produce the crystal orientation of the ROI with an accuracy of approximately 0.1 degrees.

[0050] In decision block 718 of method 700, electronic controller 150 operates to determine whether the current crystal orientation of the ROI determined in block 716 is sufficiently close to the target crystal orientation corresponding to the diffraction conditions selected in block 708. In some examples, the determination includes electronic controller 150 calculating the angular difference between the crystal orientation determined in block 716 and the target crystal orientation corresponding to the diffraction conditions selected in block 708, and also includes comparing the magnitude of the calculated angular difference with a threshold. When the calculated angular difference is less than the threshold, the current crystal orientation of the ROI is considered acceptable, otherwise it is considered unacceptable. When the current orientation is unacceptable ("No" at decision block 718), processing of method 700 is directed to block 720. When the current orientation is acceptable ("Yes" at decision block 718), processing of method 700 is directed to block 722.

[0051] The method 700 includes adjusting the orientation of the sample S (in block 720). The operation of block 720 includes the electronic controller 150 calculating an estimated first rotation angle (R1) and an estimated second rotation angle (R2) by which the sample manipulator of the sample holder 110 needs to rotate the sample S so that the crystal orientation of the ROI changes from the crystal orientation determined in block 716 to a target crystal orientation corresponding to the diffraction condition selected in block 708. The operation of block 720 also includes the electronic controller 150 generating appropriate control signals 158 for the sample manipulator to perform the R1 and R2 rotations by the calculated first rotation angle and the second rotation angle. After the R1 and R2 rotations are completed, the processing of the method 700 is directed back to block 714.

[0052] The method 700 also includes configuring the scientific instrument 100 to operate in the SEM imaging mode (in block 722). As already noted above, the SEM imaging mode also uses the BSE detector 220 to capture the BSE signal. The SEM imaging mode differs from the SACP mode in that the SEM column 102 is now configured to S-scan the impact point of the electron beam 114 across the sample without electron beam wobbling.

[0053] The method 700 also includes the electronic controller 150 acquiring a SEM image of the sample S (at block 724). An example SEM image that may be acquired at block 724 is shown in FIG. Figure 8 . The operations of block 724 include the electronic controller 150 operating the SEM column 102 to scan the electron beam 114 across the sample S in a raster pattern, and operating the BSE detector 220 to capture BSE signals corresponding to different scanned pixel locations on the sample S. The operations of block 724 further include the electronic controller 150 receiving a measurement stream representing the captured BSE signals from the BSE detector 220 via the signal 222. Based on the received measurement stream, the electronic controller 150 operates to populate a corresponding image frame suitable for reproduction and visualization, for example, on a display device connected thereto. When the operations of block 724 are completed, the method 700 terminates.

[0054] In some examples, method 700 may be repeated one or more times, for example, for different corresponding ROIs of sample S.

[0055] In some embodiments of the method 700, blocks 722 and 724 may not be present. In some other embodiments of the method 700, blocks 722 and 724 may be replaced by operations representing different applications, where the precise orientation of the sample S obtained via the operations of blocks 702 to 720 is useful. In some examples, such different applications are selected from the group consisting of thin section extraction and grinding / machining 3D structures based on the crystal orientation of the sample. Figure 8An SEM image 800 acquired in block 724 of method 700 according to one example is shown. In the example shown, sample S is a silicon-germanium layer on a silicon wafer. Due to the nearly perfect crystal orientation of the ROI of sample S under the selected Bragg conditions, a high contrast for visualizing various lattice defects via the ECCI effect is achieved. For example, several dislocations in sample S are clearly visualized as bright lines and bright areas in image 800.

[0056] Fig. 9 is a block diagram of an example computing device 900 configured to perform at least some scientific instrument support operations according to various embodiments. For example, in some embodiments, the computing device 900 executes the electronic controller 150 (see also Figure 1 , Figure 2 and Figure 7 ) In various embodiments, the support modules of the scientific instrument 100 may be implemented by a single computing device 900 or by multiple computing devices 900.

[0057] Fig. 9 The computing device 900 is illustrated as having multiple components, but any one or more of these components may be omitted or repeated depending on suitability for the application and setting. In some embodiments, some or all of the components included in the computing device 900 may be attached to one or more motherboards and packaged in a housing. In some embodiments, some of these components may be manufactured onto a single system on a chip (SoC) (e.g., the SoC may include one or more processing devices 902 and one or more storage devices 904). Additionally, in various embodiments, the computing device 900 may not include Fig. 9 The computing device 900 may include one or more of the components shown, but may include interface circuitry for coupling to the one or more components using any suitable interface (e.g., a universal serial bus (USB) interface, a high-definition multimedia interface (HDMI) interface, a controller area network (CAN) interface, a serial peripheral interface (SPI) interface, an Ethernet interface, a wireless interface, or any other suitable interface). For example, the computing device 900 may not include the display device 910, but may include a display device interface circuit (e.g., a connector and a driving circuit) capable of coupling to the external display device 910.

[0058] The computing device 900 includes a processing device 902 (e.g., one or more processing devices). As used herein, the term "processing device" refers to any device or portion of a device that processes electronic data from registers and / or memory to convert the electronic data into other electronic data that can be stored in registers and / or memory. In various embodiments, the processing device 902 may include one or more digital signal processors (DSPs), application specific integrated circuits (ASICs), central processing units (CPUs), graphics processing units (GPUs), server processors, or any other suitable processing devices.

[0059] The computing device 900 also includes a storage device 904 (e.g., one or more storage devices). In various embodiments, the storage device 904 may include one or more memory devices, such as a random access memory (RAM) device (e.g., a static RAM (SRAM) device, a magnetic RAM (MRAM) device, a dynamic RAM (DRAM) device, a resistive RAM (RRAM) device, or a conductive bridge RAM (CBRAM) device), a hard drive-based memory device, a solid-state memory device, a network drive, a cloud drive, or any combination of memory devices. In some embodiments, the storage device 904 may include a memory that shares a die with the processing device 902. In such an embodiment, the memory may be used as a cache memory and include, for example, an embedded dynamic random access memory (eDRAM) or a spin-transfer torque magnetic random access memory (STT-MRAM). In some embodiments, the storage device 904 may include a non-transitory computer-readable medium having instructions thereon that, when executed by one or more processing devices (e.g., processing device 902), cause the computing device 900 to perform any appropriate method or portions of such methods disclosed herein below.

[0060] The computing device 900 also includes an interface device 906 (e.g., one or more interface devices 906). In various embodiments, the interface device 906 may include one or more communication chips, connectors, and / or other hardware and software to manage communications between the computing device 900 and other computing devices. For example, the interface device 906 may include circuitry for managing wireless communications for transmitting data to and from the computing device 900. The term "wireless" and its derivatives may be used to describe circuits, devices, systems, methods, techniques, communication channels, etc. that can transmit data via modulated electromagnetic radiation through a non-solid medium. The term does not imply that the associated device does not contain any wires, although in some embodiments it may not contain any wires. The circuitry included in the interface device 906 for managing wireless communications may implement any of a plurality of wireless standards or protocols, including but not limited to Institute of Electrical and Electronics Engineers (IEEE) standards, including Wi-Fi (IEEE 802.11 series), IEEE 802.16 standards, Long Term Evolution (LTE) projects, and any amendments, updates, and / or revisions (e.g., Advanced LTE projects, Ultra Mobile Broadband (UMB) projects (also known as "3GPP2"), etc.). In some embodiments, the circuitry included in the interface device 906 for managing wireless communications may operate according to a Global System for Mobile Communications (GSM), General Packet Radio Service (GPRS), Universal Mobile Telecommunications System (UMTS), High Speed ​​Packet Access (HSPA), Evolved HSPA (E-HSPA), or LTE network. In some embodiments, the circuitry included in the interface device 906 for managing wireless communications may operate according to Enhanced Data GSM Evolution (EDGE), GSM EDGE Radio Access Network (GERAN), Universal Terrestrial Radio Access Network (UTRAN), or Evolved UTRAN (E-UTRAN). In some embodiments, the circuitry included in the interface device 906 for managing wireless communications may operate in accordance with code division multiple access (CDMA), time division multiple access (TDMA), digital enhanced cordless telecommunications (DECT), evolution data optimized (EV-DO) and its derivatives, and any other wireless protocols designated as 3G, 4G, 5G and higher. In some embodiments, the interface device 906 may include one or more antennas (e.g., one or more antenna arrays) configured to receive and / or transmit wireless signals.

[0061] In some embodiments, interface device 906 may include a circuit for managing wired communication, such as electrical communication protocol, optical communication protocol or any other suitable communication protocol. For example, interface device 906 may include a circuit supporting communication according to Ethernet technology. In some embodiments, interface device 906 may support both wireless and wired communication, and / or may support multiple wired communication protocols and / or multiple wireless communication protocols. For example, a first group of circuits of interface device 906 may be dedicated to shorter range wireless communication such as Wi-Fi or Bluetooth, and a second group of circuits of interface device 906 may be dedicated to longer range wireless communication such as global positioning system (GPS), EDGE, GPRS, CDMA, WiMAX, LTE, EV-DO, etc. In some other embodiments, a first group of circuits of interface device 906 may be dedicated to wireless communication, and a second group of circuits of interface device 906 may be dedicated to wired communication.

[0062] The computing device 900 also includes a battery / power circuit 908. In various embodiments, the battery / power circuit 908 may include one or more energy storage devices (e.g., batteries or capacitors) and / or circuits for coupling components of the computing device 900 to an energy source separate from the computing device 900 (e.g., coupling to AC line power).

[0063] Computing device 900 also includes display device 910 (e.g., one or more separate display devices). In various embodiments, display device 910 may include any visual indicator, such as a heads-up display, a computer monitor, a projector, a touch screen display, a liquid crystal display (LCD), a light emitting diode display, or a flat panel display.

[0064] The computing device 900 also includes additional input / output (I / O) devices 912. In various embodiments, the I / O devices 912 may include one or more data / signal transmission interfaces, audio I / O devices (e.g., microphones or microphone arrays, speakers, headphones, earbuds, alarms, etc.), audio codecs, video codecs, printers, sensors (e.g., thermocouples or other temperature sensors, humidity sensors, pressure sensors, vibration sensors, etc.), image capture devices (e.g., one or more cameras), human interface devices (e.g., keyboards, cursor control devices such as mice, styluses, trackballs, or trackpads), and the like.

[0065] Depending on the specific implementation of the scientific instrument 100 and / or the instrument portion 200, the various components of the interface device 906 and / or the I / O device 912 may be configured to output appropriate control signals (e.g., 152, 154, 156) for the various components of the scientific instrument 100, receive appropriate control / telemetry signals from the various components of the scientific instrument 100, and receive measurement streams (e.g., 162, 172, 182) from the various detectors of the scientific instrument 100. In some examples, the interface device 906 and / or the I / O device 912 include one or more analog-to-digital converters (ADCs) for converting received analog signals into digital form suitable for operations performed by the processing device 902 and / or the storage device 904. In some additional examples, the interface device 906 and / or the I / O device 912 include one or more digital-to-analog converters (DACs) for converting digital signals provided by the processing device 902 and / or the storage device 904 into analog form suitable for being communicated to the corresponding components of the scientific instrument 100.

[0066] According to an example disclosed above, for example in the Summary section and / or with reference to Figures 1 to 9 According to any one of the figures or any combination of some or all of the figures, a scientific instrument is provided, the scientific instrument comprising: a manipulator configured to controllably rotate a sample about a first rotation axis and about a second rotation axis oriented at a non-zero angle relative to the first rotation axis; an electron beam column configured to direct an electron beam to a selected impact point on the sample; a first detector configurable to detect an angularly resolved pattern of backscattered electrons emitted from the selected impact point in response to the electron beam; a second detector configured to detect a flux of backscattered electrons emitted from the selected impact point in response to the electron beam; and an electronic controller The manipulator is configured to: determine a first crystal orientation of a region of interest (ROI) within a sample based on an angle-resolved pattern of backscattered electrons collected using a first detector while operating the electron beam column to maintain the electron beam at a first fixed impact point within the ROI; operate the manipulator to place the ROI into a second crystal orientation in which an angular difference between the determined first crystal orientation and a target crystal orientation is estimated to be substantially eliminated; and determine a second crystal orientation based on a first selected area electron channeling pattern (SACP) collected using a second detector while operating the electron beam column to oscillate the electron beam at a second fixed impact point within the ROI.

[0067] In some examples of the above scientific instruments, the electronic controller is further configured to compare an angular difference between the determined second crystal orientation and the target crystal orientation to a threshold value.

[0068] In some examples of any of the above-mentioned scientific instruments, when the angular difference between the determined second crystal orientation and the target crystal orientation is less than a threshold value, the electronic controller is configured to: operate the SEM column to scan the electron beam across the sample; and acquire a SEM image of the sample based on the backscattered electron signal generated by the second detector during the electron beam scanning.

[0069] In some examples of any of the above scientific instruments, when the angular difference between the determined second crystal orientation and the target crystal orientation is greater than a threshold, the electronic controller is configured to operate the manipulator to place the ROI into a third crystal orientation in which the angular difference between the determined second crystal orientation and the target crystal orientation is estimated to be substantially eliminated.

[0070] In some examples of any of the above-mentioned scientific instruments, the electronic controller is also configured to: when operating the electron beam column to cause the electron beam to swing at a third fixed impact point within the ROI, determine a third crystal orientation based on a second SACP acquired using a second detector; and compare the angular difference between the determined third crystal orientation and the target crystal orientation with a threshold.

[0071] In some examples of any of the above-mentioned scientific instruments, when the angular difference between the determined third crystal orientation and the target crystal orientation is less than a threshold value, the electronic controller is configured to: operate the SEM column to scan the electron beam across the sample; and acquire a SEM image of the sample based on the backscattered electron signal generated by the second detector during the electron beam scanning.

[0072] In some examples of any of the above scientific instruments, when the angular difference between the determined third crystal orientation and the target crystal orientation is greater than a threshold, the electronic controller is configured to operate the manipulator to place the ROI into a fourth crystal orientation in which the angular difference between the determined third crystal orientation and the target crystal orientation is estimated to be substantially eliminated.

[0073] In some examples of any of the above-mentioned scientific instruments, the manipulator is also configured to controllably translate the sample along a first non-collinear direction, a second non-collinear direction, and a third non-collinear direction; and wherein the electronic controller is also configured to operate the manipulator so that the first fixed impact point and the second fixed impact point are juxtaposed.

[0074] In some examples of any of the above scientific instruments, the electronic controller is configured to select the target orientation based on Bragg diffraction conditions for a selected set of lattice planes of the sample.

[0075] In some examples of any of the above scientific instruments, the angle-resolved pattern enables the electronic controller to determine a first crystal orientation with a first precision; and wherein the first SACP enables the electronic controller to determine a second crystal orientation with a second precision finer than the first precision.

[0076] In some examples of any of the above scientific instruments, the second precision is at least ten times finer than the first precision.

[0077] According to another example disclosed above, for example, in the Summary section and / or with reference to Figures 1 to 9 Any one of the figures or any combination of some or all of the figures provides an automated method, the method comprising: determining a first crystal orientation of a region of interest (ROI) within a sample based on an angle-resolved pattern of backscattered electrons collected using a first detector while operating an electron beam column to maintain the electron beam at a first fixed impact point within the ROI; operating a manipulator to place the ROI in a second crystal orientation, in which the angular difference between the determined first crystal orientation and the target crystal orientation is estimated to be substantially eliminated, the manipulator being configured to controllably rotate the sample around a first rotation axis and around a second rotation axis oriented at a non-zero angle relative to the first rotation axis; and determining a second crystal orientation based on a first selected area electron channeling pattern (SACP) collected using a second detector while operating the electron beam column to swing the electron beam at a second fixed impact point within the ROI, the second detector being configured to detect a flux of backscattered electrons emitted from a selected impact point in the sample in response to the electron beam.

[0078] In some examples of the automated methods described above, the automated method further includes comparing an angular difference between the determined second crystal orientation and the target crystal orientation to a threshold value.

[0079] In some examples of any of the above automated methods, the automated method further includes: when the angular difference between the determined second crystal orientation and the target crystal orientation is less than a threshold, operating the SEM column to scan the electron beam across the sample, and acquiring a SEM image of the sample based on a backscattered electron signal generated by the second detector during the electron beam scanning.

[0080] In some examples of any of the above automated methods, the automated method further includes: when the angular difference between the determined second crystal orientation and the target crystal orientation is greater than a threshold, operating the manipulator to place the ROI into a third crystal orientation, in which the angular difference between the determined second crystal orientation and the target crystal orientation is estimated to be substantially eliminated.

[0081] In some examples of any of the above-mentioned automated methods, the automated method further includes: when operating the electron beam column so that the electron beam swings at a third fixed impact point within the ROI, determining a third crystal orientation based on a second SACP acquired using a second detector; and comparing the angular difference between the determined third crystal orientation and the target crystal orientation with a threshold.

[0082] In some examples of any of the above automated methods, the automated method further includes: when the angular difference between the determined third crystal orientation and the target crystal orientation is less than a threshold, operating the SEM column to scan the electron beam across the sample, and acquiring a SEM image of the sample based on a backscattered electron signal generated by a second detector during the electron beam scanning.

[0083] In some examples of any of the above automated methods, the automated method further includes: when the angular difference between the determined third crystal orientation and the target crystal orientation is greater than a threshold, operating the manipulator to place the ROI into a fourth crystal orientation, in which the angular difference between the determined third crystal orientation and the target crystal orientation is estimated to be substantially eliminated.

[0084] In some examples of any of the automated methods described above, the automated method further includes selecting the target orientation based on Bragg diffraction conditions for a selected set of lattice planes of the sample.

[0085] According to another example disclosed above, for example, in the Summary section and / or with reference to Figures 1 to 9 Any one of the figures or any combination of some or all of the figures provides a non-transitory computer-readable medium storing instructions that, when executed by a computing device, cause the computing device to perform operations including any of the above automated methods.

[0086] According to another example disclosed above, for example, in the Summary section and / or with reference to Figures 1 to 9According to any one of the figures or any combination of some or all of the figures, a scientific instrument is provided, the scientific instrument comprising: a manipulator configured to controllably rotate a sample about a first rotation axis and about a second rotation axis oriented at a non-zero angle relative to the first rotation axis; an electron beam column configured to direct an electron beam to a selected impact point on the sample; one or more detectors configurable to detect an angularly resolved pattern of backscattered electrons emitted from the selected impact point in response to the electron beam, and further configurable to detect a flux of backscattered electrons emitted from the selected impact point in response to the electron beam; and an electronic controller , the electronic controller is configured to: determine a first crystal orientation of the ROI within the sample based on an angle-resolved pattern of backscattered electrons collected using one or more detectors when operating the electron beam column to maintain the electron beam at a first fixed impact point within the ROI; operate the manipulator to place the ROI into a second crystal orientation, in which the angular difference between the determined first crystal orientation and the target crystal orientation is estimated to be substantially eliminated; and determine a second crystal orientation based on a first SACP collected using one or more detectors when operating the electron beam column to cause the electron beam to swing at a second fixed impact point within the ROI.

[0087] In some examples of the above-described scientific instruments, one or more detectors are implemented using a single movable pixelated BSE detector.

[0088] In some examples of any of the above-described scientific instruments, one or more detectors include a first detector that can be configured to detect an angle-resolved pattern of backscattered electrons emitted from a selected impact point in response to the electron beam; and a second detector that is configured to detect a flux of backscattered electrons emitted from the selected impact point in response to the electron beam.

[0089] In some examples of any of the above scientific instruments, the first detector is retractable.

[0090] In some examples of any of the above scientific instruments, the second detector is fixed or retractable.

[0091] According to another example disclosed above, for example, in the Summary section and / or with reference to Figures 1 to 9Any one of the figures or any combination of some or all of the figures provides an automated method, the method comprising: determining a first crystal orientation of an ROI within a sample based on an angle-resolved pattern of backscattered electrons collected using one or more detectors while operating an electron beam column to maintain the electron beam at a first fixed impact point within the ROI; operating a manipulator to place the ROI in a second crystal orientation, in which the angular difference between the determined first crystal orientation and the target crystal orientation is estimated to be substantially eliminated, the manipulator being configured to controllably rotate the sample around a first rotation axis and around a second rotation axis oriented at a non-zero angle relative to the first rotation axis; and determining a second crystal orientation based on a first SACP collected using one or more detectors while operating the electron beam column to swing the electron beam at a second fixed impact point within the ROI, the one or more detectors being configured to detect a flux of backscattered electrons emitted from a selected impact point in the sample in response to the electron beam.

[0092] According to another example disclosed above, for example, in the Summary section and / or with reference to Figures 1 to 9 According to any one of the figures or any combination of some or all of the figures, a scientific instrument is provided, which includes: an electron beam column, which is configured to direct an electron beam to a sample; a manipulator, which is configured to adjust the orientation of the sample relative to the electron beam; one or more detectors, which are used to detect backscattered electrons from the sample; and an electronic controller, which includes a processor and a memory for storing program code, wherein the memory and the program code are configured to use the processor to cause the scientific instrument to perform at least the following operations: direct the electron beam toward a region of interest (ROI) of the sample, and collect at least one electron backscatter diffraction (EBSD) pattern using one or more detectors; determine a first crystal orientation based on the at least one EBSD pattern; adjust the orientation of the sample toward a target crystal orientation via the manipulator based on the first crystal orientation; direct the electron beam toward the ROI, and collect a first selected area electron channeling pattern (SACP) using one or more detectors; determine a second crystal orientation based on the first SACP; and adjust the orientation of the sample toward a target crystal orientation via the manipulator based on the second crystal orientation.

[0093] In some examples of the above scientific instruments, the memory and the program code are further configured to, with the processor, cause the scientific instrument to acquire an image of the sample including the ROI after adjusting the orientation of the sample based on the first crystal orientation and the second crystal orientation.

[0094] In some examples of any of the above scientific instruments, the sample image is a SEM image showing crystal defects of the sample.

[0095] In some examples of any of the above scientific instruments, at least one EBSD pattern includes an angle-resolved pattern of backscattered electrons emitted from the ROI in response to the electron beam.

[0096] In some examples of any of the above scientific instruments, the first SACP represents a flux of backscattered electrons emitted from the ROI when the electron beam swings at the ROI.

[0097] In some examples of any of the above scientific instruments, the memory and the program code are further configured to, with the processor, cause the scientific instrument to acquire an image of the sample including the ROI after adjusting the orientation of the sample based on the first SACP.

[0098] In some examples of any of the above scientific instruments, to adjust the orientation of the sample towards a target crystal orientation based on EBSD, the scientific instrument is configured to: determine a first crystal orientation based on EBSD, and adjust the orientation of the sample based on the first crystal orientation.

[0099] In some examples of any of the above scientific instruments, to direct the electron beam toward the ROI and collect at least one EBSD pattern, the scientific instrument is configured to: direct the electron beam toward a first impact point within the ROI and collect the EBSD pattern, and direct the electron beam toward the ROI and collect the first SACP, the scientific instrument is configured to direct the electron beam toward a second impact point within the ROI and collect the first SACP, and wherein the samples at the first impact point and the second impact point have the same crystal orientation.

[0100] In some examples of any of the above scientific instruments, the scientific instrument is further configured to select the ROI based on a scanning electron microscopy (SEM) image of the sample before acquiring the EBSD pattern.

[0101] In some examples of any of the above scientific instruments, the target crystal orientation corresponds to a diffraction condition selected based on EBSD.

[0102] In some examples of any of the above scientific instruments, the accuracy of the orientation of the sample toward the target crystal orientation is lower than the accuracy of the orientation of the sample toward the target crystal orientation based on the first SACP.

[0103] In some examples of any of the scientific instruments described above, the one or more detectors include a first retractable detector for acquiring EBSD and a second detector for acquiring a first SACP, the first retractable detector is positioned between the sample and a pole piece of an electron column for generating the electron beam, and wherein the memory and the program code are configured to, with the processor, cause the scientific instrument to at least perform the following operations: retract the first detector before directing the electron beam toward the ROI and acquiring the first SACP.

[0104] In some examples of any of the above scientific instruments, the EBSD is acquired by positioning one or more detectors substantially perpendicular to the beam axis of the electron beam.

[0105] It should be understood that the above description is intended to be illustrative rather than restrictive. By reading the above description, many specific implementations and applications other than the examples provided will be apparent. The scope should not be determined with reference to the above description, but should be determined with reference to the full scope of the appended claims and the equivalents to which these claims are entitled. It is anticipated and intended that future developments will occur in the technology discussed herein, and the disclosed systems and methods will be incorporated into these future examples. In short, it should be understood that the present application is capable of modification and variation.

[0106] All terms used in the claims are intended to be given their broadest reasonable interpretations and their ordinary meanings as understood by those skilled in the art described herein, unless an explicit indication to the contrary is made herein. Specifically, use of singular articles such as "a," "the," "said," etc. should be understood to recite one or more of the indicated elements unless a claim recites an explicit limitation to the contrary.

[0107] The abstract is provided to allow the reader to quickly determine the nature of the technical disclosure. It should be observed that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing detailed description, it can be seen that various features are grouped together in various examples for the purpose of streamlining the disclosure. The method of the present disclosure should not be interpreted as reflecting the following intention: the claimed subject matter includes more features than those explicitly stated in each claim. Rather, as reflected in the following claims, the subject matter of the present invention lies in less than all the features of a single disclosed example. Therefore, the following claims are hereby incorporated into the detailed description, with each claim acting on its own as a separately claimed subject matter.

[0108] Unless expressly stated otherwise, each numerical value and range should be interpreted as approximate as if the value or range was preceded by the word "about" or "approximately".

[0109] Although elements in the following method claims, if any, are recited in a specific order with corresponding labels, these elements are not necessarily intended to be limited to being implemented in that specific order unless the claim recitation otherwise implies a specific order for implementing some or all of these elements.

[0110] Unless otherwise specified herein, the use of ordinal adjectives "first," "second," "third," etc. to refer to one of multiple similar objects merely indicates that different instances of such similar objects are being referred to, and is not intended to imply that the similar objects so referred to must be in a corresponding order or sequence in time, space, rank, or in any other manner.

[0111] Unless otherwise indicated herein, in addition to its ordinary meaning, the conjunction "if" may also or alternatively be interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting", and its interpretation may depend on the corresponding specific context. For example, the phrase "if it is determined" or "if [the condition] is detected" may be interpreted to mean "upon determination" or "in response to determination" or "upon detection of [the condition or event]" or "in response to detecting [the condition or event]".

[0112] Likewise, for the purposes of this specification, the terms "coupled", "connected" refer to any means known in the art or later developed, in which energy is allowed to be transferred between two or more elements, and the insertion of one or more additional elements is contemplated, although not required. Conversely, the terms "directly coupled", "directly connected", etc., imply that there are no such additional elements.

[0113] The functions of the various elements shown in the drawings, including any functional blocks marked as "processors" and / or "controllers", can be provided by using dedicated hardware and hardware capable of executing software in association with appropriate software. When provided by a processor, the function can be provided by a single dedicated processor, by a single shared processor, or by multiple separate processors (some of which can be shared). In addition, the explicit use of the term "processor" or "controller" should not be interpreted as exclusively referring to hardware capable of executing software, but may implicitly include but is not limited to digital signal processor (DSP) hardware, network processors, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), read-only memories (ROMs), random access memories (RAMs) and non-volatile storage devices for storing software. Other conventional and / or customized hardware may also be included. Similarly, any switches shown in the figure are conceptual only. Their functions can be performed by the operation of program logic, by dedicated logic, by the interaction of program control and dedicated logic, or even manually, as more specifically understood from the context, and specific techniques can be selected by the implementer.

[0114] As used in this application, the term "circuitry" may refer to one or more or all of the following: (a) a hardware circuit implementation only (such as an implementation only in analog and / or digital circuits); (b) a combination of hardware circuitry and software, such as (if applicable): (i) a combination of analog and / or digital hardware circuitry and software / firmware, and (ii) a hardware processor and software (including a digital signal processor), any portion of software and memory, which work together to cause a device such as a mobile phone or server to perform various functions; and (c) a hardware circuit and / or processor, such as a microprocessor or a portion of a microprocessor, which requires software (e.g., firmware) to operate, but when software is not required for operation, the software may not be present. This definition of circuitry applies to all uses of the term in this application, including in any claims. As another example, as used in this application, the term circuitry also covers an implementation of a hardware circuit or processor (or multiple processors) or a portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term "circuitry" also covers, for example and if applicable to a particular claim element, a baseband integrated circuit or a processor integrated circuit for a mobile device or a similar integrated circuit in a server, cellular network device, or other computing or networking device.

[0115] Those skilled in the art will appreciate that any block diagrams herein represent conceptual diagrams of illustrative circuits embodying the principles of the present disclosure. Similarly, it will be appreciated that any flow charts, flow diagrams, state transition diagrams, pseudocodes, etc. represent various processes that can be substantially represented in a computer-readable medium and thus executed by a computer or processor, regardless of whether such a computer or processor is explicitly shown.

Claims

1. A scientific instrument, comprising: an electron beam column configured to direct an electron beam toward a sample; a manipulator configured to adjust an orientation of the sample relative to the electron beam; one or more detectors for detecting backscattered electrons from the sample; and an electronic controller comprising a processor and a memory for storing program code, The memory and the program code are configured to use the processor to cause the scientific instrument to at least perform the following operations: directing the electron beam toward a region of interest (ROI) of the sample and collecting at least one electron backscatter diffraction (EBSD) pattern using the one or more detectors; adjusting the orientation of the sample toward a target crystal orientation via the manipulator based on the EBSD; directing the electron beam toward the ROI and acquiring a first selected area electron channeling pattern (SACP) using the one or more detectors; and Based on the first SACP, the orientation of the sample is adjusted toward the target crystal orientation via the manipulator.

2. A scientific instrument according to claim 1, wherein: The memory and the program code are further configured to, with the processor, cause the scientific instrument to acquire an image of the sample including the ROI after adjusting the orientation of the sample based on the first SACP.

3. The scientific instrument according to claim 1, wherein: Adjusting the orientation of the sample toward a target crystal orientation based on the EBSD includes determining a first crystal orientation based on the EBSD, and adjusting the orientation of the sample based on the first crystal orientation.

4. The scientific instrument according to claim 1, wherein: Directing the electron beam toward the ROI and acquiring at least one EBSD pattern includes directing the electron beam toward a first impact point within the ROI and acquiring the EBSD pattern, and wherein directing the electron beam toward the ROI and acquiring the first SACP includes directing the electron beam toward a second impact point within the ROI and acquiring the first SACP, and wherein the samples at the first impact point and the second impact point have the same crystal orientation.

5. A scientific instrument according to claim 4, wherein: The scientific instrument is further configured to select the ROI based on a scanning electron microscopy (SEM) image of the sample prior to acquiring the EBSD pattern.

6. The scientific instrument of claim 1, wherein: The target crystal orientation corresponds to the diffraction conditions selected based on the EBSD.

7. The scientific instrument of claim 1, wherein: The accuracy of the orientation of the sample toward the target crystal orientation is lower than the accuracy of the orientation of the sample toward the target crystal orientation based on the first SACP.

8. The scientific instrument of claim 1, wherein: The one or more detectors include a first retractable detector for acquiring the EBSD and a second detector for acquiring the first SACP, the first retractable detector being positioned between the sample and a pole piece of an electron column for generating the electron beam, and wherein the memory and the program code are configured to, with the processor, cause the scientific instrument to at least perform the following operations: retract the first detector before directing the electron beam toward the ROI and acquiring the first SACP.

9. The scientific instrument of claim 1, wherein: The EBSD is acquired by positioning the one or more detectors substantially perpendicular to a beam axis of the electron beam.

10. A scientific instrument, comprising: a manipulator configured to controllably rotate the sample about a first rotation axis and about a second rotation axis oriented at a non-zero angle relative to the first rotation axis; an electron beam column configured to direct an electron beam to a selected impact point on the sample; one or more detectors configurable to detect an angularly resolved pattern of backscattered electrons emitted from the selected impact point in response to the electron beam and further configurable to detect a flux of backscattered electrons emitted from the selected impact point in response to the electron beam; and An electronic controller, the electronic controller being configured to: determining a first crystal orientation of a region of interest (ROI) within the sample based on an electron backscatter diffraction (EBSD) pattern collected using the one or more detectors while operating the electron beam column to direct the electron beam to a first impact point within the ROI; operating the manipulator to place the ROI in a second crystal orientation to substantially eliminate an angular difference between the determined first crystal orientation and a target crystal orientation; and The second crystal orientation is determined based on a first selected area electron channeling pattern (SACP) acquired using the one or more detectors while operating the scientific instrument to direct the electron beam to a second impact point within the ROI.

11. The scientific instrument of claim 10, wherein: The electronic controller is further configured to compare an angular difference between the determined second crystal orientation and the target crystal orientation to a threshold value.

12. The scientific instrument of claim 11, wherein: When the angular difference between the determined second crystal orientation and the target crystal orientation is less than the threshold, the electronic controller is configured to: operating the electron beam column to scan the electron beam across the sample; and A SEM image of the sample is acquired based on backscattered electron signals detected by the one or more detectors during scanning of the electron beam.

13. The scientific instrument of claim 11, wherein: When the angular difference between the determined second crystal orientation and the target crystal orientation is greater than the threshold, the electronic controller is configured to operate the manipulator to place the ROI in a third crystal orientation to substantially eliminate the angular difference between the determined second crystal orientation and the target crystal orientation.

14. The scientific instrument according to claim 10, in, The manipulator is further configured to controllably translate the sample along a first non-collinear direction, a second non-collinear direction, and a third non-collinear direction; and Wherein, the electronic controller is further configured to operate the manipulator so that the first impact point and the second impact point are located at substantially the same position.

15. The scientific instrument of claim 10, wherein: The electronic controller is configured to select the target crystal orientation based on Bragg diffraction conditions for a selected set of lattice planes of the sample.

16. The scientific instrument of claim 10, wherein: The one or more detectors are implemented using a single pixelated backscattered electron detector.

17. A method for orienting a sample, the method comprising: collecting an electron backscatter diffraction pattern (EBSD) with one or more detectors while operating the electron beam column to direct the electron beam to a first impact point within a region of interest (ROI) of the sample held by the sample holder; Determining a first crystal orientation of the ROI based on the acquired EBSD; operating a manipulator coupled to the sample holder to place the ROI in a second crystal orientation to substantially eliminate an angular difference between the determined first crystal orientation and a target crystal orientation; acquiring, with the one or more detectors, a first selected area electron channeling pattern (SACP) of the ROI positioned in the second crystal orientation while operating the electron beam to direct the electron beam at a second impact point within the ROI; as well as The second crystal orientation is determined based on the acquired first SACP.

18. The method according to claim 17, further comprising: comparing the angular difference between the determined second crystal orientation and the target crystal orientation with a threshold value; In response to the angular difference being less than the threshold, operating the electron beam column to scan the electron beam across the sample and acquiring a SEM image of the sample; as well as In response to the angular difference being greater than the threshold, operating the manipulator to place the ROI in a third crystal orientation to substantially eliminate the angular difference.

19. The method according to claim 17, wherein: The sample is not removed from the sample holder between acquiring the EBSD and the SACP.

20. The method of claim 17, further comprising selecting the target crystal orientation based on the acquired EBSD.

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