Method and system for orienting specimen for inspection by charged particle microscope

Abstract

To solve the problems of the prior art.SOLUTION: In some embodiments, a scientific instrument includes a manipulator configured to controllably rotate the specimen, an electron beam column configured to direct an electron beam to a selected impact point on the specimen, and a detector configurable to detect the angle resolved pattern and the flux of backscattered electrons. The scientific instrument also includes an electronic controller configured to determine a first crystallographic orientation of the specimen on the basis of the angle resolved pattern acquired while the electron beam column is manipulated to keep the electron beam fixed on the impact point, manipulate the manipulator to place the specimen in a second crystallographic orientation that presumably eliminates the angular difference between the determined first crystallographic orientation and the target crystallographic orientation, and determine the second crystallographic orientation on the basis of the SACP acquired while manipulating the electron beam column to lock the electron beam on the impact point.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] Various embodiments relate generally, but are not limited to, charged particle microscope components, instruments, systems, and methods. Summary of the Invention

[0002] One embodiment provides a scientific instrument comprising: a manipulator configured to controllably rotate a specimen about a first axis of rotation and a second axis of rotation that is at a non-zero angle relative to the first axis of rotation; an electron beam column configured to direct an electron beam to a selected impact point on the specimen; one or more detectors configurable to detect an angle resolved pattern of backscattered electrons emitted from the selected impact point in response to the electron beam and 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 direct the electron beam to a region of interest within the specimen. and an electronic controller configured to: determine a first crystallographic orientation of the ROI based on an angle-resolved pattern of backscattered electrons acquired with one or more detectors when the electron beam column is manipulated to maintain the ROI over a first impact point within the ROI; manipulate the manipulator to place the ROI in a second crystallographic orientation that is estimated to substantially eliminate an angular difference between the determined first crystallographic orientation and the target crystallographic orientation; and determine the second crystallographic orientation based on a first selected area electron channeling pattern (SACP) acquired with the one or more detectors when the scientific instrument is manipulated to lock the electron beam relative to the sample over the second impact point within the ROI.

[0003] In some embodiments, the one or more detectors are implemented using a single movable pixelated back-scattered electron (BSE) detector.

[0004] In some other embodiments, the one or more detectors include a first BSE detector configurable to detect an angle-resolved pattern of backscattered electrons emitted from a selected impingement point in response to the electron beam, and a different second BSE detector configurable to detect a flux of backscattered electrons emitted from a selected impingement point in response to the electron beam.

[0005] Another embodiment provides an automated method, the method including: acquiring an electron backscatter diffraction pattern (EBSD) with one or more detectors as an electron beam column is manipulated to direct an electron beam onto a first impact point within a region of interest (ROI) of a sample held by a sample holder; determining a first crystal orientation of the ROI based on the acquired EBSD; manipulating a manipulator coupled to the sample holder to position the ROI at a second crystal orientation to substantially eliminate an angular difference between the determined first crystal orientation and a target crystal orientation; acquiring a first limited area electron channeling pattern (SACP) of the ROI positioned at the second crystal orientation with the one or more detectors as the electron beam is manipulated to lock the electron beam onto the second impact point within the ROI; and determining the second crystal orientation based on the acquired first SACP.

[0006] Yet another embodiment 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 methods described above.

[0007] Yet another embodiment provides a scientific instrument comprising: an electron beam column configured to direct an electron beam to a specimen; a manipulator configured to adjust an orientation of the specimen relative to the electron beam; one or more detectors for detecting backscattered electrons from the specimen; and an electronic controller including a processor and a memory for storing program code configured, using the processor, to cause the scientific instrument to at least direct the electron beam to a ROI of the specimen; acquire at least one EBSD pattern using the one or more detectors; adjust an orientation of the specimen based on the EBSD using the manipulator to a target crystallographic orientation; direct the electron beam to the ROI; acquire a first SACP using the one or more detectors; and adjust an orientation of the specimen based on the first SACP using the manipulator.

[0008] Yet another embodiment provides a scientific instrument comprising: an electron beam column configured to direct an electron beam to a specimen; a manipulator configured to adjust an orientation of the specimen relative to the electron beam; one or more detectors for detecting backscattered electrons from the specimen; and an electronic controller including a processor and a memory for storing program code configured, using the processor, to cause the scientific instrument to at least direct the electron beam to a ROI of the specimen; acquire at least one EBSD pattern using the one or more detectors; adjust an orientation of the specimen based on the EBSD using the manipulator to a targeted crystallographic orientation; direct the electron beam to the ROI; acquire an electron channeling pattern (ECP) using the one or more detectors; and adjust an orientation of the specimen based on the ECP using the manipulator to a targeted crystallographic orientation.

[0009] Yet another embodiment provides a scientific instrument comprising: an electron beam column configured to direct an electron beam to a specimen; a manipulator configured to adjust an orientation of the specimen relative to the electron beam; one or more detectors for detecting backscattered electrons from the specimen; and an electronic controller including a processor and a memory for storing program code configured, using the processor, to cause the scientific instrument to at least direct the electron beam to a region of interest (ROI) of the specimen; acquire at least one electron backscatter diffraction (EBSD) pattern using the one or more detectors; adjust an orientation of the specimen based on the EBSD using the manipulator to a targeted crystallographic orientation; direct the electron beam to the ROI; acquire a first selected area electron channeling pattern (SACP) using the one or more detectors; and adjust an orientation of the specimen based on the first SACP using the manipulator. [Brief description of the drawings]

[0010] The foregoing aspects and many of the attendant advantages associated with the present disclosure will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, in which: [Figure 1] 1 is a block diagram illustrating an exemplary scientific instrument, according to some embodiments. [Diagram 2] 2 is a block diagram illustrating a scientific instrument according to another embodiment. [Diagram 3] FIG. 3 is a block diagram illustrating the acquisition of a 2D electron diffraction pattern using the detector arrangement of FIG. 2 according to one embodiment. [Figure 4] 4 illustrates an electron diffraction pattern captured using the acquisition process of FIG. 3, according to one embodiment. [Diagram 5] FIG. 3 is a block diagram illustrating SACP measurements using the detector configuration of FIG. 2 according to one embodiment. [Figure 6] 6 illustrates an SACP captured using the acquisition process of FIG. 5, according to one embodiment. [Figure 7]2 is a flow chart illustrating a method for automated imaging of lattice defects that can be implemented using the scientific instrument of FIG. 1 in accordance with some embodiments. [Figure 8] 8 illustrates an SEM image acquired using the method of FIG. 7 according to one embodiment. [Figure 9] FIG. 1 is a block diagram of an example computing device configured to perform at least some scientific instrument supporting operations, in accordance with various embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Accurately determining the crystal orientation of a sample is an important prerequisite for high quality imaging and / or processing of the sample using a charged particle microscope. Based on the determined crystal orientation, the sample can be oriented such that the charged particle beam is aligned with the crystal structure of the sample. For example, the sample must be placed in electron channeling conditions based on its crystal orientation to perform electron channeling contrast imaging (ECCI). In another embodiment, an atomic plane of the sample can be selected based on the crystal orientation, and a thin section can be extracted by cutting along the selected atomic plane for further examination in a transmission electron microscopy (TEM) system. Applicant recognizes that electron backscatter diffraction (EBSD) patterns, electron channeling patterns (ECP), and selected area electron channeling patterns (SACP) can all determine crystal orientation. EBSD is formed by acquiring angle resolved backscattered electrons that are emitted from an impact point in response to an electron beam illuminating the impact point. ECP and SACP are formed by acquiring backscattered electrons for variations in the electron beam incidence direction relative to the crystal structure of the sample. ECP can be acquired by scanning a relatively large sample area, while SACP can be acquired by rocking the beam and / or sample while directing the electron beam substantially to one impact point or small sample area. ECP and SACP based crystal orientation estimates have higher angular resolution and accuracy compared to EBSD. However, ECP and SACP only inspect a smaller angular range compared to EBSD. ECP or SACP cannot uniquely determine crystal orientation because both methods recognize only a small portion of reciprocal space. To obtain complete information, especially for polycrystalline materials, the context provided by the EBSD method is necessary.

[0012] To address the above issues, the sample is first oriented based on EBSD and then oriented based on ECP or SACP. In some embodiments, an initial coarse alignment of the sample under test (SUT) to the Bragg condition for a selected set of crystal lattice planes is performed based on an electron backscatter diffraction (EBSD) pattern with a lower angular precision (e.g., about 1 degree). The initial coarse alignment is then refined to a higher angular precision (e.g., better than about one tenth of a degree) based on one or more selected area SACPs obtained after EBSD-based sample orientation. By performing ECP / SACP after EBSD-based sample orientation, the crystal orientation of the sample can be estimated more quickly and accurately than based on either EBSD or SACP alone. In some embodiments, the crystal orientation can be determined based on either ECP or SACP. However, for certain samples, such as polycrystalline samples, SACP is preferred because SACP can be obtained by examining a smaller sample area compared to ECP.

[0013] In some embodiments, EBSD is acquired using a retractable two-dimensional (2D) pixelated BSE detector. SACP is acquired using an annular BSD detector, which can also be used for scanning electron microscopy (SEM) imaging. SACP can be acquired after retracting the 2D pixelated BSE detector. The sample remains on the sample holder during EBSD and SACP acquisitions and between EBSD and SACP acquisitions. The orientation of the sample is adjusted by a manipulator coupled to the sample holder. An electronic controller applies suitable processing algorithms to determine adjustments for two rotation angles of the SUT and manipulates the sample manipulator to perform the corresponding rotations. In some embodiments, instead of orienting the sample to about 70 degrees relative to the incident electron beam, EBSD is acquired by placing a 2D pixelated BSE detector between the pole piece of the electron column and the sample. The 2D pixelated BSE detector may be positioned substantially perpendicular to the beam axis of the electron column.

[0014] In some embodiments, once the SUT is oriented to the two-beam diffraction condition based on the SACP, the electron beam column and the annular BSE detector may be switched to a SEM imaging mode for performing ECCI (electron channeling contrast imaging). Beneficially, the acquired SEM image has optimal contrast for clearly visualizing various lattice defects present in the SUT.

[0015] ECCI is a scanning electron microscope (SEM) technique that uses the strong dependence of the backscattered electron (BSE) signal on the orientation of crystal lattice planes relative to the incident electron beam, due to the electron channeling mechanism. Local strains in the crystal lattice, generated by strain fields associated with certain lattice defects such as dislocations, grain boundaries, stacking faults, point defects, and deformation twins, typically impose a modulation on the BSE signal that can be detected using a suitable BSE detector. As a result, the corresponding lattice defects can be visualized in the SEM image.

[0016] According to the dynamical theory of electron diffraction, optimal contrast for imaging lattice defects by ECCI is obtained when the crystal specimen under test is substantially precisely oriented to the Bragg condition (i.e., electron channeling condition or two-beam diffraction condition) for a selected set of crystal lattice planes. Even small deviations from the correct orientation can result in a significant reduction in ECCI contrast, and specimen orientation with an accuracy of about 0.1° is typically required for defect characterization and metrology. Thus, a fast and accurate method for properly orienting the SUT in an SEM instrument is critical for various ECCI applications.

[0017] Figure 1 is a block diagram illustrating a scientific instrument 100, according to some embodiments. The scientific instrument 100 includes an SEM column 102 coupled to a vacuum chamber 108. The vacuum chamber 108 houses a moveable sample holder 110 therein and can be evacuated using one or more vacuum pumps (not explicitly shown in Figure 1). A sample S to be investigated using the scientific instrument 100 is mounted in the sample holder 110 as shown in Figure 1.

[0018] In some embodiments, the sample holder 110 is independently movable parallel to the XY coordinate plane and parallel to the Z coordinate axis, with the corresponding coordinate system being illustrated by the XYZ coordinate triad depicted in FIG. 1 . In some embodiments, the sample holder 110 is rotatable with or without translation relative to the XYZ coordinate frame. In some implementations, the sample holder 110 includes a goniometer that is independently rotatable about at least mutually orthogonal eucentric tilt and azimuthal rotation axes. In other implementations, the goniometer may perform rotation about 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 exemplary sample holder suitable for rotating the sample S and adjusting the sample position relative to the electron beam is disclosed in U.S. Pat. No. 10,784,076, which is incorporated herein by reference in its entirety.

[0019] In the illustrated embodiment, the SEM column 102 comprises an electron source 112 and two or more electron beam lenses, only two of which are shown diagrammatically in Figure 1 for illustration purposes: objective lens 106 and condenser lens 116. In some embodiments, a different number of such lenses (other than two) can be used in the SEM column 102. In some embodiments, the objective lens 106 can be an ultra-high-resolution (UHR) lens.

[0020] 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 are operated to generate electric and magnetic fields that affect the electron trajectories in the electron beam 114. The scientific instrument 100 includes an electronic controller 150. The electronic controller 150 may include a processor (e.g., 902 in FIG. 9 ) and a memory (e.g., 904 in FIG. 9 ) for storing computer readable instructions. In various embodiments, by executing computer readable instructions stored in the memory, the electronic controller 150 performs at least a portion of the methods disclosed herein. For example, control signals 152, 156 generated by the electronic controller 150 are used to modify the strength and / or spatial configuration of these fields to impart desired characteristics to the electron beam 114. In general, the electron beam lenses 106 and 116, control signals 152 and 156, and other associated components of the scientific instrument 100 may be used to perform various operations to assist in various functions such as beam focusing, aberration mitigation, aperture adjustment, filtering, etc. The SEM column 102 further comprises a deflection unit 118 that may steer the orientation of the electron beam 114 in response to control signals 154 applied by an electronic controller 150. Such beam steering may be used to move a focused portion of the electron beam 114 along a desired path across the sample S and / or to change the angle of incidence of the electron beam 114 at the sample S, for example to perform a raster or vector scan of the sample.

[0021] The scientific instrument 100 also includes detectors 160, 170, 180 located within the vacuum chamber 108 in relative proximity to the sample S. During operation, the detectors 160, 170, and 180 generate streams of measurements 162, 172, and 182 that are received by the electronic controller 150. The specific types of detectors 160, 170, 180 depend on the embodiment of the scientific instrument 100 and can typically 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. Exemplary types of emissions / radiation that may be generated in this manner include, but are not limited to, x-rays, infrared, visible light, ultraviolet light, backscattered electrons, secondary electrons, Auger electrons, elastically scattered electrons, non-scattered (e.g., zero energy loss) electrons, and non-elastically scattered electrons. In various embodiments, a different number (other than three) of such detectors can be used within the scientific instrument 100. In some embodiments, some or all of the detectors 160, 170, 180 can be stored and / or replaced without equilibrating 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 annular detectors, segmented annular detectors, differential phase contrast detectors, two-dimensional (e.g., pixelated or segmented) diffraction pattern detectors, BSE detectors, electron backscatter diffraction (EBSD) detectors, and forescattered electron (FSE) detectors. Other detectors capable of detecting various of the above-mentioned types of emission / radiation can also be used in various additional embodiments.

[0022] FIG. 2 is a block diagram illustrating a scientific instrument 200 according to another embodiment. The scientific instrument 200 includes some of the same elements as the scientific instrument 100, which are indicated by the same reference numbers as in FIG. 1. The scientific instrument 200 includes one or more BSE detectors, such as one or both of detectors 210 and 220, for detecting backscattered electrons generated when the electron beam 114 (see also FIG. 1) strikes the sample S, and is further configured to communicate respective detected BSE signals 212, 222 to the electronic controller 150. In one embodiment, the BSE detector 210 is a retractable detector for acquiring EBSD patterns. The BSE detector 220 is an annular detector for acquiring SACPs. In various embodiments, the BSE detector 220 is either a fixed detector or a retractable detector. When the BSE detector 210 is deployed and in the position shown in FIG. 2, the BSE detector 220 is idle (e.g., not performing measurements). When the BSE detector 210 is retracted from the illustrated orientation, the BSE detector 220 can be activated to perform BSE measurements. In use, the BSE detector 220 can perform SACP measurements or SEM image acquisition at different times and in different operating modes of the scientific instrument 100. In various embodiments, such different operating modes employ similar probe geometries that substantially maintain the relevant geometric relationships between the electron beam 114 and the sample S.

[0023] In the illustrated embodiment, both BSE detectors 210 and 220 have respective apertures 208, 218 aligned with the longitudinal axis 115 of the SEM column 102 for allowing the electron beam 114 to pass through and impinge on the sample S. The scientific instrument 200 includes an automated manipulator 206 having five degrees of freedom, including X, Y, and Z translations and R1 and R2 rotations. In some embodiments, the manipulator 206 includes a sample holder 110. In other embodiments, the sample holder 110 is coupled to the manipulator 206 in a manner that is aligned with the desired translation and / or rotation of the sample S. In some embodiments, the movements of the manipulator 206 corresponding to the various degrees of freedom are controlled by the electronic controller 150 via control signals 158 as described above.

[0024] In some embodiments, instead of the two illustrated BSE detectors 210 and 220, the detector configuration 200 can employ a more versatile single BSE detector designed and configured to perform several types of BSE measurements, including the BSE measurements performed with the BSE detectors 210 and 220 in the embodiment illustrated in FIG. 2. 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 functionally equivalent to those performed with the illustrated BSE detectors 210 and 220 are performed using different pixel binning configurations and / or arrangements of each of such a single BSE detector. For illustrative purposes, and without any implied limitation, exemplary embodiments are described herein below with reference to the detector configuration 200 employing the illustrated BSE detectors 210 and 220. Based on the provided description, one of ordinary skill in the art will readily understand how to make and use the corresponding embodiments employing a single movable 2D pixelated BSE detector without undue experimentation.

[0025] FIG. 3 is a block diagram illustrating the acquisition of an electron diffraction pattern using a BSE detector 210 according to one embodiment. In the illustrated embodiment, the electron beam 114 irradiates the sample S by propagating along an illumination axis 304 to the sample S. 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 comprises a volume of the sample S with which the electrons of the beam 114 interact. In one embodiment, a normal 302 to the top surface of the sample S is oriented at a tilt angle θ with respect to the illumination axis 304, and the illumination axis 304 remains fixed during EBSD signal acquisition. Such an EBSD pattern may be acquired using the scientific instrument 100 of FIG. 1 or the scientific instrument 200 of FIG. 2. In another embodiment, the sample S is not tilted with respect to the illumination axis 304. In such an embodiment, the normal 302 to 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 illuminated by the electron beam 114, backscattered electrons 314 emitted from the impact point 306 are detected in an angle-resolved manner by a corresponding BSE detector, e.g. the 2D pixel array of the BSE detector 210. The signal values ​​accumulated by the individual pixels of the pixel array during the illumination intervals (downtimes) are read out therefrom and transmitted by corresponding output signals 212 to the electronic controller 150.

[0026] FIG. 4 illustrates an EBSD pattern 400 captured using the acquisition setup of FIG. 2 according to one embodiment. In the illustrated embodiment, the sample S is an electropolished tungsten specimen. The EBSD pattern 400 has multiple sets of parallel line pairs, typically called Kikuchi line pairs (or bands). The spacing and configuration of those pairs correspond to a particular crystallographic structure and orientation. The intersections of different Kikuchi line pairs in the EBSD pattern 400 are called zone axes. The angles between the lines connecting the different zone axes indicate the crystal structure of the sample S. These and other features of the EBSD pattern 400 can be quantified using suitable EBSD pattern processing algorithms. Based on such quantification, the crystal orientation of the sample S at the impact point 306 relative to the illumination axis 304 can be determined. A typical accuracy for determining the crystal orientation from an EBSD pattern such as the EBSD pattern 400 is about 1-2 degrees.

[0027] In one embodiment, the crystal orientation is determined by matching the EBSD pattern 400 to one of the known EBSD patterns (or a computer-simulated version thereof). In another embodiment, the crystal orientation is calculated by comparing the angles measured between the Kikuchi bands to theoretical interplanar angles determined using standard crystallographic principles. Several other EBSD pattern processing algorithms suitable for crystal orientation determination are reviewed, for example, in T.B. Britton, 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.

[0028] FIG. 5 is a block diagram illustrating an SACP measurement using an annular BSE detector 220 according to one embodiment. Note that the detector configuration shown in FIG. 5 can be obtained in the SACP mode of the scientific instrument 200 shown in FIG. 2, with the BSE detector 210 retracted from the arrangement shown in FIG. 2. To obtain the SACP, the SEM column 102 is manipulated to direct the electron beam 114 to an impact point 506 on the surface of the sample S and to vary the angle of incidence of the electron beam 114 in a process often referred to as beam locking. 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 by adjusting the manipulator to change the orientation of the sample relative to the beam axis. Exemplary SEM column configurations that can be used for beam locking are disclosed, for example, in U.S. Pat. No. 9,093,246, which is incorporated herein by reference in its entirety.

[0029] During operation, the incidence angle of the electron beam 114 is varied by the SEM column 102 to sample different incidence angles, for example, within a cone 510. In some embodiments, the cone 510 is a circular or elliptical cone with an apex angle ranging from about 0.05 degrees to about 15 degrees. In some related literature, the apex angle is also referred to as a "convergence" angle. In some embodiments, the convergence angle is about 0.5 degrees. Two different incidence angles corresponding to the electron beam propagation directions 502 and 504 are illustrated in FIG. 5 as examples. At different incidence angles within the cone 510, the BSE detector 220 is operated to capture and measure corresponding BSE signals. Two such BSE signals are labeled 512 and 514 and illustrated in FIG. 5. The BSE signal 512 is generated when the electron beam 114 strikes the impact point 506 from the 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 signal corresponding to different electron beam propagation directions captured by BSE detector 220 within corresponding time intervals are read therefrom and transmitted to electronic controller 150 via output signal 222.

[0030] FIG. 6 illustrates an SACP 600 captured using the acquisition setup of FIG. 5 according to one embodiment. In the illustrated embodiment, the sample S is a silicon-germanium layer on a silicon wafer. Details of the crystal structure, including crystal orientation and local lattice constants, can be obtained from the SACP by analyzing the arrangement of contrast / intensity lines therein. In one embodiment, a dictionary-based algorithm is used to determine the crystal orientation from the SACP. Dictionary indexing of the SACP can be achieved, for example, by simulating the pattern of all possible Euler angle combinations with some finite step size in the orientation space. An algorithm executed by the electronic controller 150 then operates to determine the best fit to the trial SACP. A typical accuracy with which the dictionary-based algorithm determines the crystal orientation from an SACP such as the SACP 600 is about 0.1 degrees. In various additional embodiments, other methods suitable for determining the crystal orientation from the SACP may also be applied to the SACP 600, and the crystal orientation of the ampoule S at the impact point 506 may also be determined.

[0031] In some embodiments, instead of locking the electron beam, the various incident beam angles may be achieved by locking the sample. In other embodiments, the SACP may be obtained by a combination of beam and sample locking. In yet other embodiments, the SACP may be formed by data acquired from different impact points belonging to the same grain (or having the same crystal orientation).

[0032] 7 is a flow chart illustrating an automated method 700 of imaging lattice defects using scientific instruments 100 or 200, according to some embodiments. Method 700 is described below with continued reference to Figures 1-6. It is also noted that method 700 uses three different modalities of scientific instruments, namely, EBSD, SACP, and SEM imaging modalities, as described in more detail below.

[0033] Method 700 includes configuring (at block 702) scientific instrument 100 or 200 to operate in an EBSD mode. Such a configuration mode may include positioning retractable detector 210 over the sample, as shown in FIG. 2. The act of block 702 also includes electronic controller 150 activating retractable detector 210 and deactivating detector 220 (if previously activated). In some embodiments, the act of block 702 may also include tilting sample S with respect to the electron beam and acquiring a preliminary EBSD pattern using the EBSD detector.

[0034] The method 700 also includes (at block 704) the electronic controller 150 acquiring an EBSD pattern of the sample S. An exemplary EBSD pattern that may be acquired at block 704 is the EBSD pattern 400 of FIG. 4. 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 for a region of interest (ROI) of the sample S. The operation of block 704 further includes the electronic controller 150 receiving an image frame from the detector 210 via its output signal 212, the image frame including the captured EBSD pattern. In some embodiments, the ROI is a selected grain in the polycrystalline sample S. The grain of interest may be identified and / or selected based on, for example, an SEM scan of the sample S performed prior to the operation of block 702 described above. In some other embodiments, the ROI is a selected portion of a single crystal sample S.

[0035] Method 700 also includes electronic controller 150 determining (at block 706) a crystal orientation of the ROI based on the acquired EBSD, where the crystal orientation may be determined relative to the electron beam. The operation of block 706 includes electronic controller 150 applying an EBSD pattern processing algorithm to the image frames received in block 704, for example, as described above with reference to FIG. 4. As already indicated above, a typical EBSD pattern processing algorithm obtains a crystal orientation of the ROI with an accuracy of about 1-2 degrees.

[0036] Method 700 also includes electronic controller 150 selecting (at block 708) diffraction conditions. The diffraction conditions correspond to a target crystal orientation of the ROI relative to the electron beam. For example, the ROI satisfies an electron channeling condition when placed in the target crystal orientation. In some embodiments, the diffraction conditions are selected based on the crystal orientation determined at 706. In some embodiments, the diffraction conditions are selected at block 708 based on input from an operator. In some other embodiments, the diffraction conditions are selected at block 708 based on pre-programmed criteria that reflect the purpose of the SEM imaging to be performed in the subsequent SEM imaging mode. In some cases, the diffraction conditions are selected based on defect type, space group, and other indicators of the target orientation of the ROI.

[0037] The method 700 also includes changing the orientation of the sample S (at block 710). The operation of block 710 includes the electronic controller 150 calculating an estimated first rotation angle (R1) and an estimated second rotation angle (R2) required for the sample manipulator of the sample holder 110 to rotate the sample S such that the crystal orientation of the ROI changes from the crystal orientation determined in block 706 to a crystal orientation corresponding to the diffraction condition selected in block 708. The operation of block 710 further 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 and second rotation angles. In some embodiments, the generated control signals 158 may also include instructions for selected X, Y, and / or Z translations such that the collision point 506 for the subsequent SACP mode can be placed within the same ROI. In some embodiments, the translation is selected such that collision point 506 can substantially overlap collision point 306 used in the process of block 704 (see also FIGS. 3 and 5).

[0038] Method 700 also includes configuring (at block 712) scientific instrument 100 or 200 to operate in SACP mode. Such configuration may include calibrating and / or storing the BSE detector. In one embodiment of block 712, detector 210 as shown in FIG. 2 is stored to obtain the detector configuration illustrated in FIG. 5. The operation of block 712 also includes electronic controller 150 operating detector 220.

[0039] The method 700 further includes (at block 714) the electronic controller 150 acquiring an SACP of the sample S. An exemplary SACP that may be acquired at block 714 is the SACP 600 illustrated in FIG. 6. The operation of block 714 includes the electronic controller 150 operating the SEM column 102 to lock the electron beam 114 on the impact point 506 and operating the BSE detector 220 to capture an SACP for the ROI of the sample S, for example, as described above with reference to FIG. 5. In an exemplary embodiment, the impact point 306 corresponding to block 704 and the impact point 506 corresponding to block 714 are located within the same grain. In some embodiments, 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 further includes the electronic controller 150 receiving a stream of measurements representative of the captured SACP from the BSE detector 220 via signal 222.

[0040] Method 700 also includes electronic controller 150 determining (at block 716) a crystal orientation of the ROI. The step of block 716 includes electronic controller 150 applying a suitable SACP processing algorithm, such as that described above with reference to Figure 6, to the SACP received at block 714. As already described above, a typical SACP processing algorithm obtains a crystal orientation of the ROI to an accuracy of about 0.1 degrees.

[0041] At decision block 718 of method 700, electronic controller 150 operates to determine whether the current crystal orientation of the ROI determined at block 716 is sufficiently close to the target crystal orientation that corresponds to the diffraction condition selected at block 708. In some embodiments, this determination includes electronic controller 150 calculating an angular difference between the crystal orientation determined at block 716 and the target crystal orientation that corresponds to the diffraction condition selected at block 708, and further includes comparing the magnitude of the calculated angular difference to a threshold. The current crystal orientation of the ROI is deemed acceptable if the calculated angular difference is less than the threshold, and is deemed unacceptable otherwise. If the current orientation is unacceptable ("no" at decision block 718), processing of method 700 proceeds to block 720. If the current orientation is acceptable ("yes" at decision block 718), processing of method 700 proceeds to block 722.

[0042] The method 700 includes adjusting the orientation of the sample S (at 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 must rotate the sample S such 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 further includes the electronic controller 150 generating appropriate control signals 158 for the sample manipulator to perform R1 and R2 rotations through the calculated first and second rotation angles. After the R1 and R2 rotations are completed, processing of the method 700 returns to block 714.

[0043] The method 700 also includes configuring (at block 722) the scientific instrument 100 to operate in a SEM imaging mode. As already mentioned 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 configured to scan the impact point of the electron beam 114 across the sample S without locking the electron beam.

[0044] The method 700 further includes (at block 724) the electronic controller 150 acquiring an SEM image of the sample S. An exemplary SEM image that may be acquired at block 724 is illustrated in FIG. 8. The operation of block 724 includes 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 scan pixel locations on the sample S. The operation of block 724 further includes the electronic controller 150 receiving a stream of measurements from the BSE detector 220 via signal 222, the measurements being representative of the captured BSE signals. Based on the received stream of measurements, the electronic controller 150 operates to output corresponding image frames suitable for rendering and visualization, for example, on a display device connected thereto. Once the operation of block 724 is completed, the method 700 ends.

[0045] In some embodiments, the method 700 may be repeated, for example, one or more times for each different ROI of the sample S.

[0046] 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 for which a precise orientation of the sample S obtained through the steps of blocks 702-720 is useful. In some examples, such different applications are selected from the group consisting of thin section extraction and milling / fabrication of 3D structures based on the crystal orientation of the sample. FIG. 8 illustrates an SEM image 800 acquired in block 724 of the method 700 according to one embodiment. In the illustrated example, the sample S is a silicon-germanium layer on a silicon wafer. Thanks to the nearly perfect crystal orientation of the ROI of the sample S to the selected Bragg condition, a high contrast for visualizing various lattice defects is achieved by the ECCI effect. For example, some dislocations in the sample S are clearly visualized in the image 800 as bright lines and bright areas.

[0047] 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 performs at least some operations of the electronic controller 150 (see also FIGS. 1, 2, and 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.

[0048] Although the computing device 900 of FIG. 9 is illustrated as having several components, any one or more of these components may be omitted or present as appropriate for the application and setting. In some embodiments, some or all of the components included in the computing device 900 may be mounted on one or more motherboards and enclosed in a housing. In some embodiments, some of the components may be fabricated on a single system-on-a-chip (SoC) (e.g., an 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 one or more of the components illustrated in FIG. 9, but may include interface circuitry for coupling to 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 a display device 910, but may include display device interface circuitry (eg, connector and driver circuits) capable of coupling to an external display device 910.

[0049] Computing device 900 may include 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 and converts the electronic data into other electronic data that may be stored in registers and / or memory. In various embodiments, 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.

[0050] 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 random-access memory (RAM) devices (e.g., static RAM (SRAM) devices, magnetic RAM (MRAM) devices, dynamic RAM (DRAM) devices, resistive RAM (RRAM) devices, or conductive-bridging RAM (CBRAM) devices), hard-drive-based memory devices, solid-state memory devices, network drives, cloud drives, or any combination of memory devices. In some embodiments, the storage device 904 may include memory that shares a die with the processing device 902. In such embodiments, the memory may be used as a cache memory and may include, for example, embedded dynamic random-access memory (eDRAM) or 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 that, when executed by one or more processing devices (e.g., the processing device 902), cause the computing device 900 to perform any suitable one of the methods disclosed herein below, or portions of such methods.

[0051] The computing device 900 further 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 to manage wireless communications to transfer 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 may communicate data by modulated electromagnetic radiation over a non-solid medium. This term does not imply that the associated device does not include any wiring, although in some embodiments it may not. The circuitry included in the interface device 906 for managing wireless communications may implement any of a number of wireless standards or protocols, including, but not limited to, Wi-Fi (IEEE 802.11 family), Institute for Electrical and Electronic Engineers (IEEE) standards including the IEEE 802.16 standard, the Long-Term Evolution (LTE) project (e.g., the Advanced LTE project, the Ultramobile Broadband (UMB) project (also referred to as “3GPP®2”), etc.) with any amendments, updates, and / or revisions.In some embodiments, the circuitry included in the interface device 906 for managing wireless communications may operate in accordance with a General Packet Radio Service (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 in accordance with an Enhanced Data for GSM Evolution (EDGE), GSM EDGE Radio Access Network (GERAN), Universal Terrestrial Radio Access Network (UTRAN), or Evolved UTRAN (E-UTRAN). In some embodiments, circuitry included in interface device 906 for managing wireless communications may operate according to Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Digital Enhanced Cordless Telecommunications (DECT), Evolution-Data Optimized (EV-DO), and derivatives thereof, as well as any other wireless protocols designated as 3G, 4G, 5G, and beyond. In some embodiments, interface device 906 may include one or more antennas (e.g., one or more antenna arrays) configured to receive and / or transmit wireless signals.

[0052] In some embodiments, the interface device 906 may include circuitry for managing wired communications, such as electrical, optical, or any other suitable communications protocol. For example, the interface device 906 may include circuitry to support communications according to Ethernet technology. In some embodiments, the interface device 906 may support both wireless and wired communications, and / or may support multiple wired and / or multiple wireless communications protocols. For example, a first set of circuits of the interface device 906 may be dedicated to short-range wireless communications, such as Wi-Fi or Bluetooth, and a second set of circuits of the interface device 906 may be dedicated to long-range wireless communications, such as global positioning system (GPS), EDGE, GPRS, CDMA, WiMAX, LTE, EV-DO, etc. In some other embodiments, the first set of circuits of the interface device 906 may be dedicated to wireless communications, and a second set of circuits of the interface device 906 may be dedicated to wired communications.

[0053] Computing device 900 also includes battery / power circuitry 908. In various embodiments, battery / power circuitry 908 may include one or more energy storage devices (e.g., batteries or capacitors) and / or circuitry for coupling components of computing device 900 to an energy source separate from computing device 900 (e.g., to an AC line power source).

[0054] Computing device 900 also includes a display device 910 (e.g., one or more separate display devices). In various embodiments, display device 910 may include any visual display, such as a head-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.

[0055] Computing device 900 also includes additional input / output (I / O) devices 912. In various embodiments, I / O devices 912 may include one or more data / signal transfer interfaces, audio I / O devices (e.g., a microphone or microphone array, a speaker, a headset, an earphone, an alarm, 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., cursor control devices such as a keyboard, mouse, stylus, trackball, or touchpad), etc.

[0056] Depending on the particular embodiment of the scientific instrument 100 and / or instrument portion 200, various components of the interface device 906 and / or I / O device 912 can be configured to output suitable control signals (e.g., 152, 154, 156) to various components of the scientific instrument 100, receive suitable control signals / telemetry signals from various components of the scientific instrument 100, and receive streams of measurements (e.g., 162, 172, 182) from various detectors of the scientific instrument 100. In some examples, the interface device 906 and / or I / O device 912 include one or more analog-to-digital converters (ADCs) for converting received analog signals into a digital form suitable for operations performed by the processing device 902 and / or storage device 904. In some additional embodiments, 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 an analog form suitable for communication to corresponding components of the scientific instrument 100.

[0057] According to one embodiment disclosed above, for example in the "Summary of the Invention" section and / or with reference to any one or any combination of some or all of FIGS. 1-9, a scientific instrument includes a manipulator configured to controllably rotate a specimen about a first axis of rotation and about a second axis of rotation that forms a non-zero angle with respect to the first axis of rotation, an electron beam column configured to direct an electron beam to a selected impact point on the specimen, a first detector configurable to detect an angle resolved pattern of backscattered electrons emitted from the selected impact point in response to the electron beam, and 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 configured to: determine a first crystal orientation of a region of interest (ROI) in the sample based on a backscattered electron angle-resolved pattern acquired with the first detector when the electron beam column is manipulated to maintain the electron beam on a first fixed impact point within the ROI; operate the manipulator to place the ROI in a second crystal orientation that is estimated to substantially eliminate an angular difference between the determined first crystal orientation and a target crystal orientation; and determine the second crystal orientation based on a first limited-view electron channeling pattern (SACP) acquired with the second detector when the electron beam column is manipulated to lock the electron beam on the second fixed impact point within the ROI.

[0058] In some embodiments of the above scientific instrument, the electronic controller is further configured to compare the angular difference between the determined second crystallographic orientation and the target crystallographic orientation to a threshold value.

[0059] In some embodiments of any of the above scientific instruments, when the angular difference between the determined second crystallographic orientation and the target crystallographic 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 an SEM image of the sample based on a backscattered electron signal generated by the second detector during the electron beam scan.

[0060] In some embodiments of any of the above scientific instruments, if 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 manipulate the manipulator to place the ROI in a third crystal orientation that is estimated to substantially eliminate the angular difference between the determined second crystal orientation and the target crystal orientation.

[0061] In some embodiments of any of the above scientific instruments, the electronic controller is further configured to determine a third crystal orientation based on a second SACP acquired using the second detector when the electron beam column is operated to lock the electron beam onto a third fixed impact point within the ROI, and to compare an angular difference between the determined third crystal orientation and the target crystal orientation to a threshold value.

[0062] In some embodiments of any of the above scientific instruments, when the angular difference between the determined third crystallographic orientation and the target crystallographic 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 an SEM image of the sample based on a backscattered electron signal generated by the second detector during the electron beam scan.

[0063] In some embodiments of any of the above scientific instruments, if 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 manipulate the manipulator to place the ROI in a fourth crystal orientation that is estimated to substantially eliminate the angular difference between the determined third crystal orientation and the target crystal orientation.

[0064] In some embodiments of any of the above scientific instruments, the manipulator is further configured to controllably translate the sample along first, second, and third directions that are not collinear, and the electronic controller is further configured to operate the manipulator such that the first and second fixed collision points are at the same location.

[0065] In some embodiments of any of the above scientific instruments, the electronic controller is configured to select the target orientation based on a Bragg diffraction condition for a selected set of crystal lattice planes of the sample.

[0066] In some embodiments of any of the above scientific instruments, the angular resolved pattern causes the electronic controller to determine a first crystal orientation with a first precision, and the first SACP causes the electronic controller to determine a second crystal orientation with a second precision that is finer than the first precision.

[0067] In some embodiments of any of the above scientific instruments, the second precision is at least 10 times finer than the first precision.

[0068] According to another embodiment disclosed above, for example, in the Summary of the Invention section and / or with reference to any one or any combination of some or all of FIGS. 1-9, an automated method is provided, the method including: determining a first crystallographic orientation of a region of interest (ROI) within a specimen based on an angle-resolved pattern of backscattered electrons acquired with a first detector while an electron beam column is manipulated to maintain an electron beam on a first fixed impact point within the ROI; and controlling a manipulator to position the ROI in a second crystallographic orientation that is estimated to substantially eliminate an angular difference between the determined first crystallographic orientation and a target crystallographic orientation. the manipulator is configured to controllably rotate the specimen about a first axis of rotation and about a second axis of rotation that forms a non-zero angle with respect to the first axis of rotation; and determining a second crystallographic orientation based on a first limited-area electron channeling pattern (SACP) acquired with a second detector when the electron beam column is manipulated to lock the electron beam onto a second fixed impingement point within the ROI, the second detector is configured to detect a flux of backscattered electrons emitted from a selected impingement point within the specimen in response to the electron beam.

[0069] In some embodiments of the above automated method, the automated method further includes comparing the angular difference between the determined second crystallographic orientation and the target crystallographic orientation to a threshold value.

[0070] In some embodiments of any of the above automated methods, the automated method further includes manipulating the SEM column to scan the electron beam across the sample when the angular difference between the determined second crystallographic orientation and the target crystallographic orientation is less than a threshold value, and acquiring an SEM image of the sample based on a backscattered electron signal generated by the second detector during the electron beam scan.

[0071] In some embodiments 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, manipulating the manipulator to place the ROI at a third crystal orientation that is estimated to substantially eliminate the angular difference between the determined second crystal orientation and the target crystal orientation.

[0072] In some embodiments of any of the above automated methods, the automated method further includes determining a third crystal orientation based on a second SACP acquired using a second detector when the electron beam column is operated to lock the electron beam on a third fixed impingement point within the ROI, and comparing an angular difference between the determined third crystal orientation and the target crystal orientation to a threshold value.

[0073] In some embodiments of any of the above automated methods, the automated method further includes manipulating the SEM column to scan the electron beam across the sample when the angular difference between the determined third crystallographic orientation and the target crystallographic orientation is less than a threshold value, and acquiring an SEM image of the sample based on a backscattered electron signal generated by the second detector during the electron beam scan.

[0074] In some embodiments 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, manipulating the manipulator to place the ROI at a fourth crystal orientation that is estimated to substantially eliminate the angular difference between the determined third crystal orientation and the target crystal orientation.

[0075] In some embodiments of any of the above automated methods, the automated method further includes selecting the target orientation based on a Bragg diffraction condition for a selected set of crystal lattice planes of the sample.

[0076] In accordance with yet another embodiment disclosed above, for example, in the "Summary of the Invention" section and / or with reference to any one or any combination of some or all of Figures 1-9, a non-transitory computer-readable medium is provided that stores instructions that, when executed by a computing device, cause the computing device to perform operations including any of the automated methods described above.

[0077] According to yet another embodiment disclosed above, e.g., in the Summary of the Invention section and / or with reference to any one or any combination of some or all of FIGS. 1-9, there is provided a scientific instrument comprising: a manipulator configured to controllably rotate a specimen about a first axis of rotation and about a second axis of rotation that forms a non-zero angle with respect to the first axis of rotation; an electron beam column configured to direct an electron beam to a selected impact point on the specimen; and an electron beam column configured to detect an angle resolved pattern of backscattered electrons emitted from the selected impact point in response to the electron beam, the electron beam column configured 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: determine a first crystal orientation of the ROI in the sample based on an angle-resolved pattern of backscattered electrons acquired with the one or more detectors when the electron beam column is operated to maintain the electron beam on a first fixed impact point within the ROI; operate the manipulator to position the ROI in a second crystal orientation that is estimated to substantially eliminate an angular difference between the determined first crystal orientation and a target crystal orientation; and determine the second crystal orientation based on the first SACP acquired with the one or more detectors when the electron beam column is operated to lock the electron beam on the second fixed impact point within the ROI.

[0078] In some embodiments of the above scientific instruments, one or more detectors are implemented using a single movable pixelated BSE detector.

[0079] In some embodiments of any of the above scientific instruments, the one or more detectors include a first detector configurable 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 configured to detect a flux of backscattered electrons emitted from the selected impact point in response to the electron beam.

[0080] In some embodiments of any of the above scientific instruments, the first detector is retractable.

[0081] In some embodiments of any of the above scientific instruments, the second detector is fixed or retractable.

[0082] According to yet another embodiment disclosed above, for example, in the Summary of the Invention section and / or with reference to any one or any combination of some or all of FIGS. 1-9, an automated method is provided, the method including: determining a first crystal orientation of a ROI in a sample based on an angle-resolved pattern of backscattered electrons acquired with one or more detectors while an electron beam column is operated to maintain an electron beam on a first fixed impact point within the ROI; and selecting a second crystal orientation to position the ROI in a second crystal orientation that is estimated to substantially eliminate an angular difference between the determined first crystal orientation and a target crystal orientation. The method includes manipulating a manipulator, the manipulator configured to controllably rotate the sample about a first axis of rotation and about a second axis of rotation that forms a non-zero angle with respect to the first axis of rotation; and determining a second crystal orientation based on a first SACP acquired with one or more detectors when the electron beam column is manipulated to lock the electron beam onto a second fixed impact point within the ROI, the one or more detectors configured to detect a flux of backscattered electrons emitted from a selected impact point within the sample in response to the electron beam.

[0083] According to yet another embodiment disclosed above, for example in the "Summary of the Invention" section and / or with reference to any one or any combination of some or all of Figures 1-9, there is provided a scientific instrument comprising: an electron beam column configured to direct an electron beam at 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 including a processor and a memory for storing program code, the memory and program code configuring the processor to cause the scientific instrument to at least: direct the electron beam at a sample; The method is configured to: direct an electron beam to a region of interest (ROI) of the sample; acquire at least one electron backscatter diffraction (EBSD) pattern using one or more detectors; determine a first crystallographic orientation based on the at least one EBSD pattern; adjust an orientation of the sample to a targeted crystallographic orientation based on the first crystallographic orientation using a manipulator; direct an electron beam to the ROI; acquire a first selected area electron channeling pattern (SACP) using the one or more detectors; determine a second crystallographic orientation based on the first SACP; and adjust an orientation of the sample to the targeted crystallographic orientation based on the second crystallographic orientation using a manipulator.

[0084] In some embodiments of the scientific instrument described above, the memory and program code are further configured to cause, using the processor, the scientific instrument to acquire an image of the sample including the ROI after the orientation of the sample has been adjusted based on the first crystallographic orientation and the second crystallographic orientation.

[0085] In some embodiments of any of the above scientific instruments, the image of the sample is a SEM image that shows crystalline defects in the sample.

[0086] In some embodiments of any of the above scientific instruments, the at least one EBSD pattern comprises an angle-resolved pattern of backscattered electrons emitted from the ROI in response to the electron beam.

[0087] In some embodiments of any of the above scientific instruments, the first SACP represents a flux of backscattered electrons emitted from the ROI while the electron beam is locking on the ROI.

[0088] In some embodiments of any of the above scientific instruments, the memory and program code are further configured to, using 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.

[0089] In some embodiments of any of the above scientific instruments, to adjust the orientation of the specimen towards the target crystallographic orientation based on EBSD, the scientific instrument is configured to determine a first crystallographic orientation based on EBSD, and adjust the orientation of the specimen based on the first crystallographic orientation.

[0090] In some embodiments of any of the above scientific instruments, to direct the electron beam at the ROI and acquire at least one EBSD pattern, the scientific instrument is configured to direct the electron beam at a first impact point within the ROI and acquire the EBSD pattern, and to direct the electron beam at the ROI and acquire a first SACP, the scientific instrument is configured to direct the electron beam at a second impact point within the ROI and acquire the first SACP, wherein the sample at the first impact point and the second impact point have the same crystallographic orientation.

[0091] In some embodiments of any of the above scientific instruments, the scientific instrument is further configured to select the ROI based on a scanning electron microscope (SEM) image of the sample prior to acquiring the EBSD pattern.

[0092] In some embodiments of any of the above scientific instruments, the target crystallographic orientation corresponds to a diffraction condition selected based on EBSD.

[0093] In some embodiments of any of the above scientific instruments, the precision of the orientation of the sample toward the targeted crystallographic orientation is lower than the precision of the orientation of the sample toward the targeted crystallographic orientation based on the first SACP.

[0094] In some embodiments of any of the above scientific instruments, the one or more detectors include a first retractable detector for acquiring EBSD and a second detector for acquiring the first SACP, the first retractable detector being disposed between the sample and a pole piece of an electron column for generating the electron beam, and the memory and program code are configured, using the processor, to cause the scientific instrument to retract at least the first detector before directing the electron beam at the ROI to acquire the first SACP.

[0095] In some embodiments of any of the above scientific instruments, EBSD is acquired by arranging one or more detectors substantially perpendicular to the beam axis of the electron beam.

[0096] It should be understood that the above description is intended to be illustrative and not restrictive. Many implementations and applications other than the examples provided will become apparent upon reading the above description. The scope should not be determined with reference to the above description, but instead with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. It is anticipated and intended that future developments will occur in the art discussed herein, and that the disclosed systems and methods will be incorporated into such future examples. In short, it should be understood that this application is capable of modification and variation.

[0097] All terms used in the claims are intended to be given their broadest reasonable interpretation and their ordinary meaning as understood by one skilled in the art described herein, unless expressly indicated to the contrary herein. In particular, the use of singular articles such as "a," "the," "said," etc., should be read to recite one or more of the indicated elements, unless the claims state an express limitation to the contrary.

[0098] The Abstract is provided to allow the reader to quickly ascertain the nature of the technical disclosure. The Abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the above Detailed Description, it may be seen that various features have been grouped together in various embodiments for the purpose of streamlining the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the claimed subject matter incorporates more features than are expressly recited in each claim. Rather, as the following Claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Accordingly, the following Claims are hereby incorporated into the Detailed Description with each claim standing on its own as independently claimed subject matter.

[0099] Unless expressly stated otherwise, each numerical value and range should be construed as being approximate, as if the word "about" or "approximately" were preceding that value or range.

[0100] In the method claims that follow, elements, if any, are recited in a particular order with corresponding labeling, but unless the claim description otherwise suggests a particular order for implementing some or all of the elements, the elements are not necessarily intended to be limited to being implemented in that particular order.

[0101] Unless otherwise specified herein, the use of ordinal adjectives such as "first," "second," "third," etc. to refer to one object of a plurality of similar objects is intended only to indicate 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, either temporally, spatially, in ranking, or in any other manner.

[0102] Unless otherwise specified herein, the conjunction "if" may additionally or alternatively be interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting," in addition to its plain meaning, which interpretation may depend on the corresponding specific context. For example, the phrase "when determined" or "if [a stated condition] is detected" may be interpreted to mean "upon determining" or "in response to determining" or "upon detecting [a stated condition or event]" or "in response to detecting [a stated condition or event]."

[0103] Also, for purposes of this description, the terms "couple," "coupling," "coupled," "connected," "connecting," or "connected" refer to any manner known in the art or later developed that allows energy to be transferred between two or more elements, where the intervening presence of one or more additional elements is contemplated, but not required. Conversely, the terms "directly coupled," "directly connected," and the like, imply the absence of such additional elements.

[0104] The functionality of the various elements shown in the figures, including any functional blocks labeled "processor" and / or "controller," may be provided through the use of dedicated hardware as well as hardware capable of executing software in association with appropriate software. When provided by a processor, the functionality may be provided by a single dedicated processor, by a single shared processor, or by multiple individual processors, some of which may be shared. Furthermore, explicit use of the terms "processor" or "controller" should not be construed as referring exclusively to hardware capable of executing software, and may implicitly include, without limitation, digital signal processor (DSP) hardware, network processors, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), read only memory (ROM) for storing software, random access memory (RAM), and non-volatile storage. Other hardware, conventional and / or custom, may also be included. Similarly, any switches shown in the figures are conceptual only. Those functions may be performed through the operation of program logic, through dedicated logic, through the interaction of program control and dedicated logic, or even manually, with the particular technique being selectable by the implementer, as more particularly understood from the context.

[0105] As used in this application, the terms "circuit" and "circuitry" may refer to one or more or all of the following: (a) hardware-only circuit implementations (such as implementations with only analog and / or digital circuitry); (b) combinations of hardware circuits and software (where applicable, including (i) combinations of analog and / or digital hardware circuits and software / firmware, and (ii) any portion of a hardware processor with software (including digital signal processors), software, and memory, etc., that work together to cause a device such as a cell phone or server to perform various functions); and (c) hardware circuits and / or processors, such as a microprocessor or portions of a microprocessor, that require software (e.g., firmware) to operate, but that the software may not be present when not required for operation. This definition of circuitry applies to all uses of the term in this application, including any claims. As a further example, as used in this application, the term circuitry also covers merely a hardware circuit or processor (or processors) or portions of a hardware circuit or processor, and its (or their) accompanying software and / or firmware implementations. The term circuitry also covers, for example, baseband or processor integrated circuits for mobile devices, or similar integrated circuits in servers, cellular network devices, or other computing or network devices, where applicable to particular claim elements.

[0106] Those skilled in the art will appreciate that any block diagrams herein represent conceptual views of illustrative circuitry embodying the principles of the present disclosure. Similarly, any flow charts, flow diagrams, state transition diagrams, pseudocode, or the like, may be substantially represented in a computer-readable medium and may represent various processes that may be performed by such a computer or processor, whether or not a computer or processor is explicitly depicted.

Claims

1. an electron beam column configured to direct an electron beam at a sample; a manipulator configured to adjust an orientation of the specimen relative to the electron beam; one or more detectors for detecting backscattered electrons from the sample; an electronic controller including a processor and a memory for storing program code; A scientific instrument comprising: The memory and the program code are configured to, using the processor, cause the scientific instrument to at least: directing the electron beam onto a region of interest (ROI) on the sample to acquire at least one electron backscatter diffraction (EBSD) pattern using the one or more detectors; adjusting the orientation of the sample to a target crystallographic orientation based on the EBSD using the manipulator; directing the electron beam at the ROI to acquire a first selected area electron channeling pattern (SACP) with the one or more detectors; and adjusting the orientation of the sample toward the target crystallographic orientation based on the first SACP using the manipulator. scientific equipment.

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

3. 2. The scientific instrument of claim 1, wherein adjusting the orientation of the sample towards the target crystallographic orientation based on the EBSD comprises: determining a first crystallographic orientation based on the EBSD; and adjusting the orientation of the sample based on the first crystallographic orientation.

4. 2. The scientific instrument of claim 1, wherein directing the electron beam into the ROI to acquire at least one EBSD pattern comprises directing the electron beam to a first impact point in the ROI to acquire the at least one EBSD pattern, and directing the electron beam into the ROI to acquire the first SACP comprises directing the electron beam to a second impact point in the ROI to acquire the first SACP, wherein a crystallographic orientation of the sample at the first impact point and the second impact point is the same.

5. the manipulator is further configured to controllably translate the sample along first, second, and third non-collinear directions; The scientific instrument of claim 4 , wherein the electronic controller is further configured to manipulate the manipulator such that the first impact point and the second impact point are substantially co-located.

6. The scientific instrument of claim 1 , wherein the scientific instrument is further configured to select the ROI based on a scanning electron microscope (SEM) image of the sample prior to acquiring the EBSD pattern.

7. The scientific instrument of claim 1 , wherein the target crystallographic orientation corresponds to a diffraction condition selected based on the EBSD.

8. 2. The scientific instrument of claim 1, wherein the precision of the orientation of the sample toward the targeted crystallographic orientation is less than the precision of the orientation of the sample toward the targeted crystallographic orientation based on the first SACP.

9. 2. 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 disposed between the sample and a pole piece of an electron column for generating the electron beam, and the memory and the program code are configured to use the processor to cause the scientific instrument to at least retract the first retractable detector before directing the electron beam to the ROI and acquiring the first SACP.

10. 10. A scientific instrument according to claim 1, wherein the EBSD is obtained by positioning the one or more detectors substantially perpendicular to a beam axis of the electron beam.

11. The scientific instrument of claim 1 , wherein the one or more detectors are implemented with a single pixelated backscattered electron detector.

12. 1. A method for orienting a specimen, comprising the steps of: acquiring an electron backscatter diffraction pattern (EBSD) with one or more detectors as an electron beam column is operated to direct an electron beam onto a first impact point within a region of interest (ROI) of the sample held by a sample holder; determining a first crystallographic orientation of the ROI based on the acquired EBSD; and manipulating a manipulator coupled to the sample holder to place an ROI in a second crystallographic orientation to substantially eliminate an angular difference between the determined first crystallographic orientation and a target crystallographic orientation; acquiring, with the one or more detectors, a first selected area electron channeling pattern (SACP) of the ROI oriented at the second crystallographic orientation while the electron beam is steered to direct the electron beam onto a second impact point within the ROI; determining the second crystal orientation based on the obtained first SACP; method.

13. comparing the determined angular difference between the second crystal orientation and the target crystal orientation with a threshold value; responsive to the angular difference being less than the threshold, manipulating the electron beam column to scan the electron beam across the sample to obtain a SEM image of the sample; and in response to the angular difference being greater than the threshold, manipulating the manipulator to place the ROI in a third crystallographic orientation to substantially eliminate the angular difference. The method of claim 12.

14. The method of claim 12 , wherein the sample is not removed from the sample holder between acquiring the EBSD and acquiring the SACP.

15. 13. The method of claim 12, further comprising selecting the target crystallographic orientation based on a Bragg diffraction condition for a selected set of crystal lattice planes of the sample.

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