JP2006114304A - Automatic aberration correction method and device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic aberration correction method and a device in which a regular operator can perform simultaneously alignment, chromatic aberration correction, and geometric aberration correction without being conscious of aberration correction with respect to the automatic aberration correction method and device. <P>SOLUTION: The device is constructed of an abstraction means 15 for extracting a shape of charged particle beams from the surface image of the sample, a calculating means 15 for computing the axial shifting amount of the device, chromatic aberration amount, and geometric aberration amount by the shape of the charged particle beams extracted, and a feedback means which automatically applies a feedback to an aberration corrector 6 or an objective lens 4, or a stigma 7 until the axial shifting amount, chromatic aberration amount, and geometric aberration amount become to have prescribed values or less. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an automatic aberration correction method and apparatus.

  A scanning electron microscope (SEM) will be described as an example of a sample surface observation apparatus using charged particles. FIG. 5 is a diagram showing a configuration example of a conventional apparatus. This figure shows a scanning electron microscope equipped with an aberration corrector. An electron beam 2 is emitted from the emitter 1, and the electron beam 2 incident on the aberration corrector 6 is controlled by the lens 3 acting on the electron beam 2, and the electron beam 2 emitted from the aberration corrector 6 is used as the objective lens 4. To converge on the surface of the sample 5.

  The electron beam 2 is scanned on the sample surface, and the secondary electrons 8 emitted from the sample surface in synchronization with the scanning are detected by the secondary electron detector 9, whereby an image is displayed on the CRT 17 in synchronization with the scanning signal. Display as. Since the detection efficiency of the secondary electrons 8 is usually low, noise is removed by the normal image integrator 10. An image from which noise has been removed is displayed on the CRT 17.

  The energy shift controller 14 acts on the emitter 1 to change the emitter potential by a minute amount. Then, it is used for the purpose of performing feedback for aberration correction to the aberration corrector 6 based on the obtained image. The aberration correction controller 13 acts on the aberration corrector 6 to correct chromatic aberration. The stigma controller 12 acts on the stigma 7 to correct astigmatism. As the aberration corrector, a technique using a multipole is known (for example, see Non-Patent Document 1).

  Hereinafter, the technique shown in Non-Patent Document 1 will be described as an example. FIG. 6 is a diagram showing the configuration of the aberration corrector and the trajectory of the electron beam passing through it. In the figure, 6 is an aberration corrector. The multipoles are composed of four stages of multipoles, and are shown as a first multipole element 6a, a second multipole element 6b, a third multipole element 6c, and a fourth multipole element 6d, respectively. Usually, the multipole of each stage is a multipole of 8 or more. The electron beam 2 is simultaneously subjected to convergence / divergence by the first multipole element 6a. Now, as shown in the figure, let the electron beam 2 subjected to the diverging action be the X orbit 6e, and the electron beam 2 subjected to the convergence action be the Y orbit 6f.

  The intensity of the first multipole element 6a is adjusted so that the Y orbit 6f passes through the center of the second multipole element 6b. Further, the strength of the second multipole element 6b is adjusted so that the X orbit 6e passes through the center of the third multipole element 6c. At this time, in the second multipole element 6b, since the Y orbit 6f passes through the center of the second multipole element 6b, only the X orbit 6e receives a lens action. Similarly, since the X orbit 6e passes through the center of the third multipole element 6c, only the Y orbit 6f receives a lens action. Thus, the Y orbit 6f of the electron beam 2 must pass through the center of the second multipole element 6b, and the X orbit 6e must pass through the center of the third multipole element 6c.

  As shown in FIG. 6, after the electron beam 2 is aligned so as to pass the above-described predetermined trajectory inside the aberration corrector 6, the aberration corrector 6 corrects chromatic aberration and geometric aberration of the entire system at the same time. Adjusted to At this time, correction is usually made from chromatic aberration. The reason is that since the multipole field used when correcting chromatic aberration newly generates geometric aberration, the geometric aberration of the entire system changes after correcting chromatic aberration. Therefore, it is necessary to correct the geometric aberration after the change.

  As the geometric aberration, there are usually a plurality of geometric aberrations of the third order or less, and it is necessary for the aberration corrector 6 to correct all of them. Some of these multiple geometric aberrations are independent of each other, but some may interfere with each other. Usually, they cannot be corrected at once, and it is necessary to make corrections repeatedly to reduce the overall aberration. is there. The multipole elements 6a to 6d have their own optical axes depending on the number of poles, and the trajectory of the electron beam 2 passing through the aberration corrector 6 shifts from a predetermined trajectory in the process of correcting chromatic aberration and geometric aberration. Therefore, it is necessary to correct chromatic aberration and geometric aberration while aligning.

  As described above, in order to correct the aberration of the entire system using the aberration corrector 6, the alignment, chromatic aberration correction and geometric aberration correction of the electron beam 2 passing through the aberration corrector 6 are satisfied at the same time. Must be controlled so that. Conventionally, the above-described control of the aberration corrector 6 is manually performed by an operator who is sufficiently familiar with the characteristics of the aberration corrector 6.

  This manual correction method is described in detail in Non-Patent Document 1 described above. In summary, in chromatic aberration correction, the potential of the emitter 1 (see FIG. 5) is shifted by + ΔEa and −ΔEa. The operator confirms how the image is blurred from the charged particle image on the CRT 17, and the amount of chromatic aberration of the apparatus is estimated by experience and intuition, and is corrected by changing the lens intensity of the aberration corrector 6.

In geometric aberration correction, the lens intensity of a part of the multipole element (for example, quadrupole element) constituting the aberration corrector 6 is shifted by + Vn and −Vn, and the image is blurred similarly from the shifted charged particle image. The operator confirms this on the CRT 17 to estimate the amount of geometric aberration of the apparatus based on experience and intuition, and correct it by changing the lens strength of the aberration corrector 6. Similarly to the alignment, the lens intensity of a part of the multipole element (for example, quadrupole element) constituting the aberration corrector 6 is shifted by + Vn and −Vn, and the operator changes the direction of the shifted charged particle image on the CRT 17. By checking, the amount of axial deviation of the apparatus is estimated based on experience and intuition, and correction is performed by changing the lens strength of the aberration corrector 6. A method for detecting geometric optical aberrations up to the third order in a scanning microscope including a point light source, a lens, an object, and a detector is known (see, for example, Patent Document 1).
Special table 2003-521801 gazette Aberration correction in a low voltage SEM by multipole corrector (Nuclear Instrument and Methods in Physics Research A 363 (1995) 316-325)

  As described above, the conventional aberration correction is performed by the operator by wobbling or shifting the lens intensity of a plurality of multipoles constituting the aberration corrector 6 in the charged particle image displayed on the CRT 17. From the moving direction of the image and the size of the blur, the alignment of the charged particle beam passing through the aberration corrector 6, the chromatic aberration correction, and the geometric aberration correction must be manually performed simultaneously by experience and intuition, Even an experienced operator has a problem that it is difficult to perform aberration correction and requires a lot of time.

  In addition, the charged particle image is blurred by shifting the lens intensity, and it is difficult for the operator to judge the amount of axial deviation (alignment), the amount of chromatic aberration, and the amount of geometric aberration from the amount of blur, and the correction accuracy is insufficient. To do. In addition, there is a problem that human error is involved. In addition, since axis deviation, chromatic aberration, and geometric aberration interfere with each other, even if only one of them is corrected, the other changes, and there is a problem that it is difficult to apply feedback. In addition, there are multiple aberrations that need to be corrected, and they must be judged and classified from the SEM image, the size must be judged, and the operation of the aberration corrector must be fully understood. Therefore, there is a problem that a general operator cannot operate.

  The present invention has been made in view of these problems, and automatically controls an aberration corrector that has a complicated structure and is difficult to operate, so that an ordinary operator is not aware of aberration correction, and alignment and chromatic aberration. An object of the present invention is to provide an automatic aberration correction method and apparatus capable of simultaneously performing correction and geometric aberration correction.

  (1) The invention described in claim 1 is a step of extracting a charged particle beam shape from a sample surface image, and a step of calculating an axis deviation amount, a chromatic aberration amount, and a geometric aberration amount of the apparatus from the extracted charged particle beam shape. And a step of automatically applying feedback to the aberration corrector, the objective lens, or the stigma until the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration are below predetermined values.

  (2) The invention described in claim 2 is an extraction means for extracting a charged particle beam shape from a sample surface image, and calculates an axis deviation amount, a chromatic aberration amount, and a geometric aberration amount of the apparatus from the extracted charged particle beam shape. A calculation unit; and a feedback unit that automatically applies feedback to the aberration corrector, the objective lens, or the stigma until the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration become a predetermined value or less. Features.

(3) The invention described in claim 3 is characterized by comprising an aberration determining device that monitors the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration, and automatically determines whether or not correction is repeated.
(4) The invention according to claim 4 is characterized in that the determination as to whether or not the correction is repeated is performed using a threshold value set in advance for each of the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration.

  (5) In the invention according to claim 5, the threshold is for each axis deviation, chromatic aberration, and geometric aberration to be controlled, and monitors whether all thresholds are satisfied, and at least one of the plurality of thresholds is monitored. The correction is repeated until the threshold is satisfied.

(6) The invention according to claim 6 is characterized in that, among a plurality of controlled objects, the one with the maximum calculated amount is preferentially corrected among the axial deviation, chromatic aberration, and geometric aberration.
(7) The invention according to claim 7 displays the extracted charged particle beam shape, the calculated amount of axial deviation, the calculated amount of chromatic aberration, and the calculated amount of geometric aberration on a display means. It is characterized by.

(8) The invention according to claim 8 is characterized in that autofocus and / or autostigma is performed after correcting the amount of axial deviation.
(9) The invention according to claim 9 is characterized in that autofocus and / or autostigma is performed after correcting chromatic aberration.

  (10) The invention according to claim 10 is characterized in that autofocus and / or autostigma is performed after correcting geometric aberration.

(1) According to the first aspect of the present invention, an ordinary operator can simultaneously perform alignment, chromatic aberration correction, and geometric aberration correction without being aware of aberration correction.
(2) According to the second aspect of the invention, an ordinary operator can perform alignment, chromatic aberration correction, and geometric aberration correction at the same time without being aware of aberration correction.

(3) According to the third aspect of the present invention, it is possible to determine whether or not the correction of the axis deviation amount, the chromatic aberration amount, and the geometric aberration amount is repeated.
(4) According to the invention described in claim 4, whether or not to correct the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration is determined using a threshold value for each amount of axial deviation, amount of chromatic aberration, and amount of geometric aberration. Can be done.

  (5) According to the invention described in claim 5, the amount of axial deviation is obtained by repeating the correction until at least one threshold is satisfied among a plurality of thresholds provided for each of the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration. Either the chromatic aberration amount or the geometric aberration amount can be corrected.

  (6) According to the invention described in claim 6, the axis deviation correction or the aberration correction is promptly corrected by preferentially correcting the axis deviation amount, the chromatic aberration amount, and the geometric aberration amount having the largest value. can do.

  (7) According to the seventh aspect of the invention, by displaying the charged particle beam shape, the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration on the display means, the state of correction can be recognized, and the operator Can be supported.

(8) According to the invention described in claim 8, automatic aberration correction can be performed promptly.
(9) According to the invention described in claim 9, automatic aberration correction can be performed promptly.
(10) According to the invention described in claim 10, automatic aberration correction can be performed promptly.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram showing an embodiment of the present invention. The same components as those in FIG. 5 are denoted by the same reference numerals. In the figure, 1 is an emitter emitting a charged particle beam, 2 is an electron beam emitted from the emitter 1, 3 is a lens acting on the electron beam 2, and 6 is various corrections of the electron beam 2 subjected to the lens action. An aberration corrector to be performed, 7 is a stigma for correcting astigmatism, 4 is an objective lens for focusing the electron beam 2 on the sample 5, 5 is a sample, 8 is a secondary electron emitted from the sample 5, and 9 is the secondary electron. It is a secondary electron detector that detects secondary electrons 8.

  10 is an image accumulator that integrates images to make the secondary electron image strong against noise, 14 is an energy shift controller that shifts the potential of the emitter 1 that emits charged particles, and 13 is an aberration corrector for correcting aberrations. An aberration correction controller for providing a control signal for the purpose, 12 is a stigma controller for adjusting the stigma 7, and 11 is an objective lens controller for controlling the objective lens 4. Reference numeral 15 denotes an automatic aberration correction device that controls these components. For example, a computer is used as the automatic aberration correction device 15. The automatic aberration correction device 15 is connected to the energy shift controller 14, the aberration correction controller 13, the stigma controller 12, the objective lens controller 11, and the image integrator 10. Reference numeral 17 denotes a CRT which is connected to the automatic aberration corrector 15 and displays various information. The operation of the apparatus configured as described above will be described as follows.

  An electron beam 2 is emitted from the emitter 1, and the electron beam 2 incident on the aberration corrector 6 is controlled by the lens 3 acting on the electron beam 2. The electron beam 2 emitted from the aberration corrector 6 is controlled by the objective lens 4. It converges on the surface of the sample 5. The electron beam 2 is scanned on the surface of the sample, and secondary electrons 8 emitted from the surface of the sample 5 in synchronization with the scanning are detected by the secondary electron detector 9, whereby an image is displayed on the CRT 17 in synchronization with the scanning signal. Display as. Since the detection efficiency of the secondary electrons 8 is usually low, noise is removed by the image integrator 10.

  The stigma 7 corrects astigmatism. The energy shift controller 14 shifts the potential of the emitter 1. The aberration correction controller 13 controls the lens intensity of the aberration corrector 6. The objective lens controller 11 controls the lens intensity of the objective lens 4. The stigma controller 12 controls the lens strength of the stigma 7. The automatic aberration correction device 15 acquires a charged particle image from the image integrator 10, automatically calculates the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration of the device, and the aberration correction controller 13 as necessary. Set the chromatic aberration correction lens strength and the geometric aberration correction lens strength.

  Further, it instructs the stigma controller 12 to correct astigmatism as necessary. Further, the objective lens controller 11 is instructed to focus as necessary. Further, in order to acquire a charged particle image for measuring the amount of chromatic aberration, the energy shift controller 14 is instructed to shift the potential of the emitter. Further, in order to acquire a charged particle image for measuring the amount of axial deviation and the amount of geometric aberration, the aberration correction controller 13 is instructed to shift the lens intensity of the aberration corrector 6.

  The configuration and operation of the aberration corrector 6 are described in detail in Non-Patent Document 1. The configuration and operation of the automatic aberration corrector 15 according to the present invention will be described below with reference to FIG. An electron beam 2 is emitted from the emitter 1, and the electron beam 2 incident on the aberration corrector 6 is controlled by the lens 3 acting on the electron beam 2. Then, the electron beam 2 emitted from the aberration corrector 6 is converged on the surface of the sample 5 by the objective lens 4.

  The electron beam 2 is scanned on the surface of the sample 5, and secondary electrons 8 emitted from the surface of the sample 5 in synchronization with the scanning are detected by the secondary electron detector 9. Then, the detected secondary electron signal is displayed on the CRT 17 in synchronization with the scanning signal. Since the detection efficiency of the secondary electrons 8 is usually low, noise is removed by the image integrator 10.

Although the configuration and operation of the aberration corrector 6 are detailed in Non-Patent Document 1 described above, the operation of the automatic aberration corrector 15 according to the present invention will be described below.
FIG. 2 is a block diagram showing an embodiment of the automatic aberration corrector 15. In the figure, reference numeral 15a denotes a beam shift instruction device for instructing the energy shift controller 14 to shift the potential of the emitter 1 by ± ΔEa, and 15b denotes a lens intensity for instructing the lens intensity of the aberration corrector 6 to be shifted. A shift instruction device, 15c is an automatic alignment device that aligns the trajectory of the charged particle beam passing through the aberration corrector 6, and 15d is an autofocus device that instructs the objective lens controller 11 to focus the charged particle image. It is.

  15e is an auto stigma device for instructing the stigma controller 12 to take the astigmatism of the charged particle image, 15f is an automatic chromatic aberration correction device for correcting chromatic aberration of the entire system, and 15g is an automatic geometry for correcting geometric aberration of the entire system. An aberration correction device, 15h is synchronized with the beam shift instruction device 15a or the lens intensity shift instruction device 15b, acquires a charged particle image and extracts a charged particle beam shape, and 15i indicates the obtained charged particle beam. This is an aberration quantification apparatus that quantifies the amount of axial deviation, chromatic aberration, and geometric aberration from the shape.

  15j determines whether correction is made from the quantified axis deviation amount, chromatic aberration amount, and geometric aberration amount, and the automatic alignment device 15c automatically determines from the quantified axis deviation amount, chromatic aberration amount, and geometric aberration amount. The chromatic aberration corrector 15f and the automatic geometrical aberration corrector 15g are instructed to correct, and are instructed to correct the focus and astigmatism of the charged particle image, and the potential of the emitter is shifted in order to obtain the charged particle image. And an aberration determination device that instructs to shift the lens intensity of the aberration corrector 6.

  The operation of the autofocus device 15d is a conventional technique. For example, the lens intensity of the objective lens 4 is swept to search for the lens intensity that maximizes the contrast of the charged particle image. The operation of the auto stigma device 15e is a conventional technique. For example, the lens intensity of the stigma 7 is swept to find the lens intensity that maximizes the contrast of the charged particle image. Reference numeral 20 denotes a sample surface image (SEM image). The operation of the automatic aberration corrector 15 configured as described above will be described as follows.

  When the apparatus shown in FIG. 1 operates, secondary electrons are detected by the secondary electron detector 9 and image integration for noise removal is performed by the image integrator 10. As a result, a sample surface image 20 as shown in FIG. 2 is obtained. The beam shape extraction device 15h takes a sample surface image and calculates a beam shape 15k. The beam shape is an image having a specific shape and density. The beam shape 15k is input to the subsequent aberration quantification device 15i. The aberration quantification apparatus 15i calculates the amount of axial deviation, chromatic aberration, and geometric aberration of the apparatus from the extracted charged particle beam shape.

  The aberration quantification device 15i gives the aberration determination device 15j the amount of axial deviation, chromatic aberration, and geometric aberration of the device. The aberration determining device 15j monitors the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration, and automatically determines whether correction is repeated. According to this embodiment, the aberration determination device 15j can determine whether to repeat correction of the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration.

  In this case, the aberration determination device 15j has a threshold value for each axis deviation amount, chromatic aberration amount, and geometric aberration amount, and repeats feedback by comparing the obtained axis deviation amount, chromatic aberration amount, and geometric aberration amount with the respective threshold values. It can be determined whether or not. Specifically, it is determined whether or not the obtained axis deviation amount, chromatic aberration amount, and geometric aberration amount are larger than the respective threshold values provided. When the obtained axis deviation amount, chromatic aberration amount, and geometric aberration amount are larger than the respective threshold values, feedback for correction is repeated, and when the axial deviation amount, chromatic aberration amount, and geometric aberration amount are smaller than the threshold values, Cancel feedback correction. According to this embodiment, it is possible to determine whether or not to repeat the feedback using the threshold values provided for each of the axis deviation amount, the chromatic aberration amount, and the geometric aberration amount.

  The aberration determination device 15j includes a beam shift instruction device 15a, a lens intensity shift instruction device 15b, an automatic alignment device 15c, an auto focus device 15d, an auto stigma device 15e, an automatic chromatic aberration correction device 15f, and an automatic geometric aberration correction device 15g as necessary. A correction signal is given to. In this case, the correction signal can be given in the order from the top beam shift instruction device 15a, but the correction can be given in any order. A feedback signal is given to each device so that the amount of axial deviation, chromatic aberration, and geometric aberration are reduced.

  FIG. 3 is a flowchart showing an example of the operation of the aberration determining apparatus. The function automatic selection unit 18 performs automatic alignment (S1) and determines the result (S2). Further, autofocus is performed (S3), and the result is judged (S4). Further, auto stigma is performed (S5), and the result is judged (S6). Further, automatic chromatic aberration correction is performed (S7), and the result is judged (S8). Further, automatic geometric aberration correction is performed (S9), and the result is judged (S10). The determination result is fed back to the function automatic selection unit 18, and based on this, the function automatic selection unit 18 gives a feedback signal to each function.

  According to this embodiment, by repeating the correction until the at least one threshold is satisfied among the plurality of threshold values provided for the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration, the amount of axial deviation, the amount of chromatic aberration, Any of the geometric aberration amounts can be corrected.

  In addition, according to this embodiment, the axis deviation correction, the aberration correction, and the aberration correction can be quickly corrected by preferentially correcting the one having the largest value among the axis deviation amount, the chromatic aberration amount, and the geometric aberration amount. It can be corrected.

  In this case, the aberration determination device 15j determines which function is to be performed as necessary. For example, since the alignment may change when the lens condition is changed, control is performed such that the alignment is always performed. A feedback signal to each component based on the correction value is given, a secondary electron image emitted from the sample surface is obtained, a charged particle beam shape is obtained from the obtained secondary electron image, and feedback correction control as described above is performed. Do. If the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration obtained from the respective threshold values become smaller, the feedback process is terminated.

  According to the present invention, since the current amount of axial deviation, amount of chromatic aberration, and amount of geometric aberration are quantified, the operation state of the automatic aberration corrector 15, for example, a GUI (graphical user on the CRT) as shown in FIG. The interface 30 can display the beam shape 25, the amount of axial deviation of the apparatus, the amount of chromatic aberration, the amount of geometric aberration, and their history, thereby assisting the operator. FIG. 4 is a diagram showing a state of the display unit according to the present invention. In the figure, reference numeral 25 denotes a beam shape, and A to G are, for example, aberration, an amount of axial deviation, etc., and these A to G are displayed as time passes in the lower stage. The horizontal axis represents time, and the vertical axis represents aberration, the amount of axial deviation, and the like.

  According to the present invention, autofocus and / or autostigma can be performed after correcting the amount of axial deviation. Alternatively, autofocus and / or autostigma can be performed after correcting chromatic aberration. Alternatively, autofocus and / or autostigma can be performed after correcting the geometric aberration. In either case, automatic aberration correction can be performed quickly.

It is a block diagram which shows one embodiment of this invention. It is a block diagram which shows one embodiment of an automatic aberration corrector. It is a flowchart which shows an example of operation | movement of an aberration judgment apparatus. It is a figure which shows the mode of the display part by this invention. It is a figure which shows the structural example of a conventional apparatus. It is a figure which shows the structure of an aberration corrector, and the locus | trajectory of the electron beam passing through the inside.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Emitter 2 Electron beam 3 Lens 4 Objective lens 5 Sample 6 Aberration corrector 7 Stigma 8 Secondary electron 9 Secondary electron detector 10 Image accumulator 11 Objective lens controller 12 Stigma controller 13 Aberration correction controller 14 Energy shift control 15 Automatic aberration correction device 16 CRT

Claims (10)

Extracting a charged particle beam shape from a sample surface image;
Calculating the amount of axial misalignment, the amount of chromatic aberration, and the amount of geometric aberration of the apparatus from the shape of the extracted charged particle beam;
Automatically applying feedback to the aberration corrector, the objective lens, or the stigma until the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration are below a predetermined value;
An automatic aberration correction method comprising: Extraction means for extracting the charged particle beam shape from the sample surface image;
A calculation means for calculating the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration of the apparatus from the shape of the extracted charged particle beam;
Feedback means for automatically applying feedback to the aberration corrector, the objective lens, or the stigma until the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration are below a predetermined value;
An automatic aberration correction device configured to include:   The automatic aberration correction device according to claim 2, further comprising an aberration determination device that monitors the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration, and automatically determines whether correction is repeated.   4. The automatic aberration correction apparatus according to claim 3, wherein the determination as to whether or not to repeat the correction is performed using a threshold value set in advance for each of the amount of axial deviation, the amount of chromatic aberration, and the amount of geometric aberration.   The threshold value is for each axis deviation, chromatic aberration, and geometric aberration to be controlled, monitoring whether or not all threshold values are satisfied, and repeating correction until at least one threshold value among the plurality of threshold values is satisfied. The automatic aberration correction device according to claim 4.   6. The automatic aberration correction device according to claim 5, wherein a plurality of control targets, which are the largest, among the misalignment, chromatic aberration, and geometric aberration, are preferentially corrected.   3. The automatic aberration according to claim 2, wherein the extracted charged particle beam shape, the calculated amount of axial deviation, the calculated amount of chromatic aberration, and the calculated amount of geometric aberration are displayed on a display means. Correction device.   3. The automatic aberration correction apparatus according to claim 2, wherein autofocus and / or autostigma is performed after correcting the amount of axial deviation.   3. The automatic aberration correction apparatus according to claim 2, wherein autofocus and / or autostigma is performed after correcting chromatic aberration.   3. The automatic aberration correction apparatus according to claim 2, wherein autofocus and / or autostigma is performed after correcting the geometric aberration.

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