JPH10199780A - Beam calibration method for charged beam equipment - Google Patents

Abstract

(57) [Summary] [Problem] Accurate calibration can be performed by considering the effect of beam drift and making the effect of drift during beam calibration the same as during actual writing. An optical system for focusing an electron beam,
Blanking electrode 1 for turning on / off the electron beam
3, a deflector 19 for positioning the electron beam at a desired position on the sample surface 22 or scanning a desired region on the sample surface 22, and detecting secondary electrons generated by irradiating the electron beam. In an electron beam drawing apparatus provided with an electron detector 23, a specific mark 2 generated by scanning a specific mark on a sample surface with an electron beam using a deflector 19
When the next electron is detected by the detector 23 and the position for irradiating the electron beam is calibrated based on the detected information,
The electron beam is turned on / off by using the blanking electrode 13 during the scanning of the electron beam for the irradiation position calibration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a beam calibration method for a charged beam apparatus, and more particularly to a beam calibration method for calibrating a beam position, a beam shape, and the like.

[0002]

2. Description of the Related Art In recent years, photolithography, which has become the mainstream of fine pattern formation technology with the increase in the density of integrated circuits, has been pointed out by its limitations. ) Is progressing rapidly.

[0003] In electron beam lithography, unlike photolithography in which a device pattern of one chip is exposed at a time, drawing is performed by connecting lines one by one or minute regions of several to several tens of microns. Then, a device pattern of one chip is formed.

For example, a method of forming a linear pattern using a rectangular (square) beam will be briefly described with reference to FIG. As shown in FIG. 10, when a pattern in which several straight lines are arranged is formed, the pattern is divided into drawing units that are divided by broken lines in the drawing, and drawing is performed collectively for each drawing unit.

First, control is performed using a deflecting means so that the beam is at the position A while the beam is off. When the position is determined, the beam is turned on and drawing is performed for a predetermined time, and after a predetermined time has elapsed, the beam is turned off. Next, the beam is controlled using the deflecting means so as to come to the area B, and the beam is turned on for a predetermined time. Thereafter, the same cycle as C, D, E,... Is repeated to form one pattern.

Recently, a technique has been developed in which a larger area including a plurality of patterns (for example, an area where broken lines in the drawing are combined) is collectively exposed by one drawing. Even in this case, the pattern is formed by the drawing cycle of determining the position of the area and drawing and moving to the next position.

As described above, in electron beam lithography,
A pattern is formed by repeatedly turning off the beam, determining the position, and turning on the beam to perform writing. For this reason,
Unless the beam formation and the writing position for each writing unit can be accurately determined, a highly accurate device pattern cannot be formed. Therefore, it is important and indispensable to correctly perform beam calibration for calibrating the beam shape or position before starting writing.

Next, the beam calibration method will be briefly described with reference to FIG. 11 taking a position calibration method as an example. FIG.
M in (a) is a mark formed on the sample surface. A large number of marks M are arranged in a matrix, but in this example, only the marks M at the four corners and the center are shown for simplicity. In addition, the mark M is accurately arranged, and its position is accurately known.

At the time of beam calibration, the beam is scanned, and the beam emitted from the mark generated when the beam
The position is measured by detecting the next electron. FIG. 11B shows data obtained by this measurement. When calibration is not performed, for example, it appears that there is a mark at the position of the mark in the figure, but the actual coordinates are at the position of the mark. Therefore, the optical system of the lens barrel is adjusted so that the detected beam position matches the actual coordinates. At this time, in the calibration so far, the beam was kept irradiated during the beam calibration.

FIG. 12 shows a method for calibrating the beam shape. As shown in FIG. 12A, a beam is scanned on a fine mark M arranged on a sample surface, and secondary electrons obtained by this are detected by a detector. FIG. 12B shows a detection signal obtained by this measurement. The position of 50% of the signal intensity is defined as the beam size L, and the optical system of the lens barrel is adjusted so that this size matches the actual size. At this time, in the conventional calibration, the beam was kept irradiated during the calibration.

On the other hand, with the progress of pattern miniaturization in recent years, uncontrollable beam deflection due to charge-up of contaminants in the lens barrel, which has not conventionally been a problem, has begun to become a problem. This is because charges accumulate in contaminants attached due to the interaction between the residual gas in the lens barrel and the electron beam, form an uncontrollable (difficult) electric field, and deflect the beam (beam drift). . This phenomenon naturally affects the beam calibration. However, in the conventional method, the effect of beam drift that appears during beam calibration is not always the same as the effect that appears during actual writing, and there is a problem that complete calibration has not been completed due to the difference between the two. there were.

[0012]

As described above, in the conventional beam calibration method, no consideration is given to beam drift, and the effect of beam drift has the same effect as during actual writing. There was a problem that accurate calibration was not possible.

The present invention has been made in view of the above circumstances, and has as its object to consider the effect of beam drift and to reduce the influence of drift during beam calibration to the same extent as during actual writing. Accordingly, it is an object of the present invention to provide a beam calibration method for a charged beam apparatus capable of performing accurate calibration.

[0014]

[Means for Solving the Problems]

(Structure) In order to solve the above problem, the present invention employs the following structure. That is, the present invention provides a charged beam optical system for focusing a charged beam, blanking means for turning on and off the charged beam, and positioning the charged beam at a desired position on a sample surface, or A charged beam apparatus comprising: a deflecting unit for scanning a desired area on a surface; and a detecting unit for detecting secondary particles generated by irradiating the charged beam. A secondary particle generated by scanning a specific mark on the surface with a charged beam is detected by the detection unit, and when calibrating a position to irradiate the charged beam based on the detected information, During the scanning of the charged beam for the calibration of the irradiation position, the charged beam is turned on / off using the blanking means.

The present invention also provides a charged beam optical system for focusing a charged beam, blanking means for turning on and off the charged beam, and positioning the charged beam at a desired position on a sample surface. Or a deflection means for scanning a desired area on the sample surface, and a detection means for detecting secondary particles generated by irradiating the charged beam, wherein the deflection means is When a secondary particle generated by scanning a specific mark on a sample surface with a charged beam using the detecting means is detected by the detecting means, and the beam shape of the charged beam is calibrated based on the detected information. During the scanning of the charged beam for the beam shape calibration, the charged beam is turned on / off by using the blanking means.

Here, preferred embodiments of the present invention include the following. (1) The on-off time of the charged beam during the calibration of the charged beam shall be set to the average value of the on-time and the average value of the off-time of the charged beam during the original operation of the charged beam device. (2) The time during which the charged beam is turned on and off during the calibration of the charged beam shall be set to the mode of the ON time of the charged beam and the mode of the OFF time during the original operation of the charged beam apparatus. (3) The ratio of the time for turning on and off the charged beam during the calibration of the charged beam shall be set to the ratio of the average value of the on-time of the charged beam during the original operation of the charged beam device to the average value of the off-time. . (4) Set the ratio of the ON / OFF time of the charged beam during the calibration of the charged beam to the ratio of the mode of the ON time of the charged beam and the mode of the OFF time during the original operation of the charged beam device. To do. (5) The amount of deflection of the charged beam caused by the charging of contaminants adhering to the component itself or the contaminant attached to the component inside the charged beam optical system barrel of the charged beam device is measured, and the measured deflection is saturated. The amount of deflection is determined, and the time from when the charged beam is turned on until the amount of deflection reaches 90% of the saturated deflection amount is defined as t1, and the time during which the charged beam is turned on and off during calibration of the charged beam is defined as t1. Be shorter than each. (6) The amount of deflection of the charged beam caused by the charging of contaminants adhering to the component itself or the contaminant attached to the component in the column of the charged beam optical system of the charged beam device is measured, and the measured deflection is saturated. The amount of deflection is determined, and the time from when the charged beam is turned on until the amount of deflection reaches 90% of the saturated deflection amount is defined as t2. Before the calibration of the charged beam, the time is the same as that of the charged beam calibration. Waiting while repeating ON / OFF, and starting charged beam calibration after the waiting time t2 has elapsed. (7) The beam on and off times during beam calibration must each be shorter than 1 second. (8) Change the scanning time or the number of scans of the beam during the beam calibration of the charged beam device according to the ON / OFF time of the charged beam during the calibration of the charged beam. (9) When performing calibration without turning off the beam in the beam calibration of the charged beam apparatus, the S / N ratio of the signal detected by the secondary electron detector becomes a value necessary for performing the beam calibration. When the number of times of scanning of the charged beam is required n times or the scanning time is t3 hours, r = (on time + off time) / (on time) The number of times n ′ of scanning of the beam or the scanning time is t3 ′ times is set to be longer or longer than the value determined by n ′ = r × n or t3 ′ = r × t3. (10) The secondary particles are secondary electrons or reflected electrons. (11) The charged beam device is an electron beam drawing device.

The present invention also provides an optical system for focusing a charged beam, blanking means for turning on / off the charged beam, and positioning the charged beam at a desired position on a sample surface. Deflecting means for scanning a desired area on the sample surface, and detecting means for detecting secondary electrons generated by irradiating the charged beam, and using the deflecting means, In a charged beam apparatus that detects secondary electrons generated by scanning a specific mark and calibrates the beam shape or beam irradiation position of the charged beam, the beam shape or beam irradiation position of the charged beam is corrected. A controller for synchronizing the deflection means and the blanking means according to a predetermined rule is provided.

Further, according to the present invention, in the charged beam apparatus having the above-mentioned configuration, the predetermined rule sets the beam on / off time during the beam calibration, and sets the average value of the charged beam on / off time during the actual operation of the apparatus. , Or a constant multiple thereof, and does not scan on the specific mark during beam-off of the charged beam. To realize this, the average time of beam-on, beam-off, and scanning of the charged beam It has a function of calculating and setting timing. (Function) According to the present invention, the charged beam is turned on / off by the blanking means during the scanning of the charged beam for the calibration of the charged beam, so that the calibration taking into account the beam drift which has not been considered in the past can be performed. The calibration can be performed more accurately than the conventional method.
Specifically, the optical system can be adjusted by reproducing the charged state generated in the charged beam optical system during writing, that is, beam calibration can be performed under substantially the same conditions as in actual writing. for that reason,
The effect of the beam drift can be effectively suppressed, and highly accurate adjustment can be realized.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In the present embodiment, an electron beam drawing apparatus is used as an example of the charged beam apparatus. (First Embodiment) FIG. 1 is a schematic configuration diagram showing an electron beam writing apparatus according to a first embodiment of the present invention.

In the figure, reference numeral 11 denotes an electron gun.
The electron beam emitted from the electron beam is focused by a condenser lens 12 and is applied to a blanking aperture 14 via a deflection electrode (blanking electrode) 13 for turning on and off the beam. The beam is deflected by the blanking electrode 13 and is applied to a predetermined position of the aperture 14. That is, in the beam-on state, the aperture 1
The beam passes through the hole of No. 4 and is irradiated to positions other than the hole of the aperture 14 when the beam is off, so that the beam is blocked. As a result, on / off of the beam is realized.

The beam that has passed through the blanking aperture 14 is shaped into a rectangle (square) by the first shaping aperture 15 and then focused by the projection lens 16.
Deflected by the shaping deflector 17, the second shaping aperture 1
8 is illuminated. Due to the overlap between the aperture 15 and the aperture 18, a rectangular beam shape having a desired size can be obtained. The shape is adjusted by constantly deflecting the beam during writing according to the size and shape of the writing pattern.
A desired shape is formed.

The beam formed by the operation of the aperture 18 and the shaping deflector 17 is converged by the objective lens 21 and illuminated at a desired position on the sample surface 22 by the objective deflector 19 for positioning. During normal writing, the beam is turned off using the blanking electrode 13 to perform positioning, and after the position is determined, the beam is turned on. After the beam is turned on, irradiation is continued for a certain period of time, then the beam is turned off, and the objective deflector 19 is adjusted so that the beam can move to the next irradiation position.

In this apparatus, the objective surface deflector 19 is used at the time of beam calibration, and the sample surface 22 on which the mark is formed is used.
The upper side is scanned, the secondary electrons are captured by the detector 23, and information on the beam position or the beam shape is obtained. The timing of the scanning of the objective deflector 19 and the on / off timing of the blanking electrode 13 is controlled by the controller 24, so that calibration can be performed while appropriately synchronizing.

(Second Embodiment) FIGS. 2 and 3 are schematic views for explaining a beam calibration method for an electron beam lithography apparatus according to a second embodiment of the present invention. In this embodiment,
An example of a beam calibration method using the device of the first embodiment will be described.

Reference numeral 31 in FIG. 2A denotes a detection mark formed on the sample surface. The beam 32 is continuously scanned from the position A to the position B in the drawing. FIG. 2B shows signals detected at this time. FIG. 3 shows the relationship between the beam position at this time, the ON / OFF state of the beam, and time. The vertical axis in the figure indicates the on / off state and the beam position. The horizontal axis indicates time.

In the calibration of the beam shape, first, the shaping deflector 17 in FIG. 1 is appropriately set so that a beam shape expected as a desired shape is obtained. 1 so that the beam is irradiated to the position A with the beam turned off.
The parameters of the objective deflector 19 are set.

Next, the beam is turned on, the beam is scanned by the objective deflector 19, and the beam is moved to the position B.
At this time, the movement takes ton time. As soon as the beam moves to B, the beam is turned off.
The parameters of the objective deflector 19 are set so as to come to the position. During this time, tset time is required. At the position A, the beam is turned off and the apparatus waits for the time toff, and after the time elapses, the beam is turned on and scanning starts. This operation is repeated until a required S / N ratio is obtained.

Based on the signals obtained as described above, the optical system or the shaping deflector is adjusted so that a desired beam shape can be obtained. Here, ton is, for example, 100 msec, and toff and tset are 40 msec and 60 msec, respectively.
It is.

As described above, in the present embodiment, the beam shape is calibrated while turning the beam on and off in a state close to the actual operation of the apparatus. Calibration accuracy could be improved.

(Third Embodiment) FIG. 4 shows a third embodiment of the present invention.
FIG. 9 is a schematic diagram for explaining a beam calibration method of the electron beam writing apparatus according to the embodiment. This embodiment is a modification of the second embodiment, and is a description of a beam position calibration method.

In the drawing, reference numerals 41 are marks for position detection, which are formed in a large number on the sample surface in a matrix. However,
In this embodiment, for simplicity, it is assumed that they are formed at four corners and the center of the sample surface. Further, this mark is accurately formed, and its position is known in advance.

The beam position is calibrated by using the beam 42 on the sample surface.
And secondary electrons generated when the beam passes through the mark 41 are detected by the detector 43 to obtain information on the position. At this time, the beam is repeatedly turned on and off such that the beam is turned on for the time ton and then turned off for the time toff during the scanning of the beam.

Here, it is necessary to appropriately set the on / off time and the scanning speed so that the beam does not turn off during scanning on the mark 41. Also, ton is, for example, 50 mse
c and toff are also set to 50 msec.

As described above, also in the present embodiment, the beam shape is calibrated while turning the beam on and off in a state close to the actual operation of the apparatus, so that the calibration accuracy is improved as in the first embodiment. I was able to.

Next, the basis for improving the calibration accuracy by turning the beam on and off will be described with reference to FIGS. 5, 6, and 7. FIG. FIG. 5A is a diagram schematically illustrating a method of measuring a beam drift. In the figure, 51 indicates a beam, 52 indicates a blanking electrode, and 53 indicates a blanking aperture. Reference numeral 54 denotes a deflecting electrode, which corresponds to an electrode of an objective deflector or an electrode of a shaping deflector. 55 is an aperture.

In order to measure the beam drift, the beam is first set at the position indicated by the solid line by the deflection electrode 54. The electrons passing through the aperture 55 are measured by the Faraday cup 56. After waiting for a while in this state, scattered electrons and the like from the aperture 55 are charged on the electrode surface. An extra electric field is formed by this charging, and the beam is deflected. This electric field moves the beam to the position indicated by the dotted line.
Then, since the cross-sectional area of the beam cut by the aperture 55 changes, the amount of current incident on the Faraday cup 56 changes. FIG. 5B shows the change in the current. ΔI in the figure indicates the beam drift amount.

FIG. 6 shows the result of measurement while turning the beam on and off. The vertical axis indicates the beam drift amount (deflection amount), and the horizontal axis indicates time. As can be seen from the figure, the drift amount differs when the measurement is repeated while the beam is on and off while the beam is on, and when the time ratio is changed even when the beam is turned on and off. In any case, the drift amount saturates after a certain period of time has elapsed since the start of the measurement. Here, the time from turning on the beam until reaching 90% of the drift saturation amount ΔI is defined as t1.
Note that this time t1 is almost the same when the beam is turned on / off and measured in the same manner.

For example, FIG. 7 shows a result obtained when beam calibration is performed in the state of the area A in FIG. FIG.
(A) shows a case where the beam shape has been calibrated, and the shape before calibration is indicated by a solid line, a wavy line, and a dashed line. The solid line shows the shape when there is no drift as measured in FIG. 6, and the dashed line and the dashed line show the measurement results when there is a drift. Thus, the three are measured differently in shape.

The shape to be actually matched is the two-dot chain line in the figure, but the parameters of the deflector and the like are corrected in consideration of the difference between the two-dot chain line and the measured shape. Actually, the beam calibration may be performed including the drift amount. However, it can be seen that the correction amount differs by Δx between when the beam is turned on and off and when it is not performed. This Δx corresponds to ΔI ′ in FIG. Since the beam is repeatedly turned on and off during the actual operation of the apparatus, if calibration is performed while the beam is on, an error will occur by Δx.

FIG. 7B shows the beam position before calibration when the beam position is corrected. ☆ indicates the position to be actually adjusted, ○ indicates the position before calibration when there is no drift, △
Marks and marks indicate the case where beam on / off is performed while the beam is on at the position where there is a beam drift. In this case as well, it can be seen that an error occurs by Δx if the beam calibration is performed while the beam is on as in the case of the beam shape calibration.

As can be seen from the above, in the embodiments described above, it is most effective to set the beam on / off time to the same value as the actual apparatus operating condition. If the on and off times during the actual drawing are not constant, the average value may be used. Further, a time setting method such as setting the ON / OFF time when a pattern requiring the highest accuracy is drawn or setting the ON / OFF time most frequently may be used.

Further, beam scanning time, signal S / N
If it is not possible to set the same time as the actual writing due to the ratio, the position of the mark to be scanned, or the like, first, the ratio between the ON and OFF times of the beam may be set to the same condition as during the actual writing. Further, if the time is within the time t1 shown in FIG. 6, if the ratio of the on / off time is set to the same value as during the actual drawing, more accurate accuracy can be obtained.

From the results of experiments actually conducted by the present inventors, sufficient accuracy was obtained if the ON and OFF times were set within 1 second. (Fourth Embodiment) FIG. 8 is a diagram showing a beam calibration method of an electron beam writing apparatus according to a fourth embodiment of the present invention. The basic method is the same as the second and third embodiments. The difference from the second and third embodiments is that, as shown in FIG. 8, a waiting time t2, for example, 15 minutes, is provided until the start of calibration. Beam on / off during this time,
And their ratios are the same as at the time of calibration. Note that this t2
Is the time from turning on the beam to reaching 90% of the drift saturation.

If such a waiting time is not provided,
Because the beam drifts during the initial tens of minutes, there is a possibility that the correction value changes near the start and end of the beam calibration. However, the error can be suppressed by waiting for the beam to be saturated as in the present embodiment.

In this stand-by, the beam may be kept at one place, or the scanning is actually started, and the data acquisition is started after a predetermined time. . However, the beam must reach the sample surface, and the beam must be turned on and off.

In the above embodiment, the calibration method has been mainly described. However, when data is taken in, a sufficient S
/ N ratio must be obtained. In the conventional method, a sufficient signal is obtained because the beam remains on, but a sufficient S / N ratio may not be obtained due to the off time. In this case, it is possible to improve the S / N ratio by using a method such as reducing the scanning speed or increasing the number of scans.

In addition, this determination method is as follows. When the beam is turned on, the number of scans is set to n, or the scan time is set to t3 time, and r = (on time + off time) / (on time) is used. By setting the number of scans n 'or the scan time during calibration by turning off t3' to n '= n.times.r and t3' = t3.times.r, the same S / N ratio as in the beam-on state can be obtained. Can be

(Fifth Embodiment) FIG. 9 shows a fifth embodiment of the present invention.
FIG. 9 is a schematic diagram for explaining a beam calibration method of the electron beam writing apparatus according to the embodiment. In the present embodiment, the third
The third embodiment is a modification of the third embodiment. The difference from the third embodiment is that the electron beam does not continuously scan the sample surface, but jumps over an area without the mark 91, and emits the beam 92 only in the vicinity of the mark. Is to scan.

When jumping in an area without the mark 91, the beam 92 is off. If necessary to keep the on / off ratio constant, the apparatus waits for a certain period of time after the jump with the beam off. Conversely, the beam may be turned on and off during a jump in order to keep the beam on / off ratio constant.

Also in this case, the beam shape can be calibrated while turning the beam on and off in a state close to the actual operation of the apparatus, and the same effect as in the third embodiment can be obtained.

The present invention is not limited to the above embodiments. In the embodiment, the beam deflecting means is an electrode. However, the present invention is not limited to the electrode. A coil for electromagnetic deflection may be used, or a combination of electrostatic deflection and electrode deflection may be used.

The charged beam apparatus is not limited to an electron beam drawing apparatus, but may be applied to a microscope or any other apparatus which uses an electron beam of a predetermined shape after deflecting and scanning. Further, the present invention can be applied to an ion beam apparatus using an ion beam instead of an electron beam.

Further, in the embodiment, the secondary electrons are detected by the irradiation of the electron beam. However, reflected electrons, transmitted electrons, X-rays or the like may be detected instead. Further, in the case of an ion beam device, secondary electrons, reflected ions, transmitted ions, or X-rays may be detected. In addition, various modifications can be made without departing from the scope of the present invention.

[0054]

As described above in detail, according to the present invention, the calibration of the beam shape or the position while repeating the ON / OFF of the beam can be performed under substantially the same conditions as the actual drawing. And the effect of beam drift on beam calibration can be minimized.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an electron beam writing apparatus according to a first embodiment.

FIG. 2 is a schematic diagram for explaining a beam calibration method according to a second embodiment.

FIG. 3 is a signal waveform chart for explaining a beam calibration method according to a second embodiment.

FIG. 4 is a schematic diagram for explaining a beam calibration method according to a third embodiment.

FIG. 5 is a schematic diagram showing the basis for improving the calibration accuracy by turning on / off the beam.

FIG. 6 is a schematic diagram showing the grounds for improving the calibration accuracy by turning the beam on and off.

FIG. 7 is a schematic diagram showing a basis for improving calibration accuracy by turning on / off a beam.

FIG. 8 is a signal waveform diagram for explaining a beam calibration method for an electron beam device according to a fourth embodiment.

FIG. 9 is a schematic view showing a beam calibration method for an electron beam device according to a fifth embodiment.

FIG. 10 is a schematic diagram showing a method of forming a linear pattern using a rectangular beam.

FIG. 11 is a schematic diagram for explaining a beam position calibration method.

FIG. 12 is a schematic diagram for explaining a beam shape calibration method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Electron gun 12 ... Condenser lens 13 ... Blanking electrode 14 ... Blanking aperture 15 ... 1st shaping aperture 16 ... Projection lens 17 ... Shaping deflector 18 ... 2nd shaping aperture 19 ... Objective deflector 21 ... Objective lens 22 ... Sample surface 23 ... Secondary electron detector 24 ... Controller 31,41,51,91 ... Mark 32,42,92 ... Electron beam 43 ... Detector 52 ... Blanking electrode 53 ... Blanking aperture 54 ... Deflection electrode 55 ... Aperture 56 ... Faraday cup

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kanji Wada 1 Tokoba, Komukai Toshiba-cho, Saisaki-ku, Kawasaki-shi, Kanagawa

Claims (7)

[Claims] 1. A charged beam optical system for converging a charged beam, blanking means for turning on / off the charged beam, and positioning the charged beam at a desired position on a sample surface, or A charged beam apparatus comprising: a deflecting unit for scanning a desired area on a surface; and a detecting unit for detecting a secondary particle generated by irradiating the charged beam. A secondary particle generated by scanning a specific mark on a surface with a charged beam is detected by the detection unit, and when calibrating a position to irradiate the charged beam based on the detected information, The charged beam device is turned on and off by using the blanking means during scanning of the charged beam for irradiation position calibration. Calibration method. 2. A charged beam optical system for focusing a charged beam, blanking means for turning on / off the charged beam, and positioning the charged beam at a desired position on a sample surface, or A charged beam apparatus comprising: a deflecting unit for scanning a desired area on a surface; and a detecting unit for detecting a secondary particle generated by irradiating the charged beam. A secondary particle generated by scanning a specific mark on a surface with a charged beam is detected by the detection means, and when the beam shape of the charged beam is calibrated based on the detected information, Wherein the charged beam is turned on / off by using the blanking means during scanning of the charged beam for shape correction. Calibration method. 3. The on-off time of the charged beam during the calibration of the charged beam is determined by the average of the on-time of the charged beam or the average of the mode and off-time during the original operation of the charged beam apparatus. The beam calibration method for a charged beam apparatus according to claim 1, wherein the value is set to a value or a mode, respectively. 4. The ratio of the time for turning on and off the charged beam during the calibration of the charged beam is determined by calculating the average or mode value of the on-time of the charged beam and the off-time during the original operation of the charged beam device. 3. The beam calibration method in the charged beam apparatus according to claim 1, wherein the ratio is set to an average value or a mode value ratio. 5. The method according to claim 1, further comprising measuring a deflection amount of a charged beam caused by charging of a part in the lens barrel of the charged beam optical system of the charged beam apparatus or a contaminant attached to the part, and measuring the deflection amount of the charged beam. The saturation deflection amount that saturates is obtained, and the time from when the charged beam is turned on until the deflection amount reaches 90% of the saturation deflection amount is defined as t1, and the charged beam is turned on during the calibration of the charged beam. 5. The beam calibration method in the charged beam apparatus according to claim 1, wherein the off time is set shorter than t1. 6. The method according to claim 1, further comprising measuring a deflection amount of a charged beam generated by charging the contaminant adhering to the component itself or the contaminant attached to the component in the column of the charged beam optical system of the charged beam apparatus. The amount of saturation deflection that saturates is determined, and the time from when the charged beam is turned on until the deflection amount reaches 90% of the saturation deflection amount is defined as t2. 5. A beam calibration method in a charged beam apparatus according to claim 1, wherein the apparatus waits while repeating on / off at the same time as that described above, and starts calibration of the charged beam after a lapse of the waiting time t2. . 7. An optical system for converging a charged beam, blanking means for turning on / off the charged beam, and positioning the charged beam at a desired position on a sample surface or on the sample surface. Deflecting means for scanning a desired area of the laser beam, and 2 generated by irradiating the charged beam.
Detecting means for detecting secondary electrons generated by scanning a specific mark on the sample surface using the deflecting means, and detecting the beam shape or beam irradiation of the charged beam. In a charged beam apparatus for performing position calibration, a controller is provided that performs calibration of the beam shape or the beam irradiation position of the charged beam while synchronizing the deflection unit and the blanking unit according to a predetermined rule. Charged beam device.