JP3859388B2 - Electron beam drawing apparatus and electron beam blanking method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electron beam drawing apparatus capable of blanking an electron beam applied to a drawing material with a low voltage.
[0002]
[Prior art]
As the density of semiconductor elements increases, high-precision drawing is required. The drawing dimension in the spot beam drawing apparatus is about to be 10 nm or less. In order to draw such an ultrafine dimension, a thin beam and a fine scan increment for scanning this are required.
[0003]
As scan increments become finer, faster scanning is required. For example, when the high resolution resist sensitivity is 250 μC / cm ² , the beam current is 1 nA, and the scan increment is 2 nm, the scan increment frequency is 100 MHz. When the beam scanning becomes faster in this way, the beam blanking response for controlling the beam blocking and beam injection for each drawing pattern requires a high-speed response equal to or higher than the beam scanning frequency.
[0004]
Conventional beam blanking control uses an electron optical system that forms an object point image corresponding to the beam image on the material surface at the center (deflection main surface) of a single stage deflector. A diaphragm was provided directly below to receive the deflected beam. However, since the beam at the stop position where the beam is received has a spread, in order to block the beam, the size of the stop must be larger than the size of the beam.
[0005]
In addition, the size of this stop has to use a relatively large stop in order to facilitate beam axis alignment. As a countermeasure, an electron optical system is used in which the blanking deflector is arranged in two stages and an object point image corresponding to the beam image on the material surface is formed in the middle (the main deflection surface of the two-stage deflection system). In addition, a method is used in which a beam blocking diaphragm is arranged in the middle (object point image position) of the two-stage blanking deflector.
[0006]
Also in this case, since the aperture diameter of the blocking diaphragm must be increased to some extent for alignment of the beam axis, although the size of the beam to be deflected is small, 70 to 80% of the deflection voltage is required until the beam is blocked. Requires a voltage of the order. The deflection voltage requires a higher voltage as the accelerating voltage of the drawing apparatus becomes higher, and the response speed becomes longer as the deflection voltage becomes higher.
[0007]
Hereinafter, it demonstrates still in detail using figures. FIG. 1 shows a conventional electron beam drawing apparatus, in which 1 is an electron gun. The electron beam EB generated from the electron gun 1 is focused by the first lens 2, the second lens 3, and the third lens 4. The first lens 2 images the crossover C0 generated by the electron gun 1 on the main surface of the blanking deflector 5 as the crossover C1.
[0008]
The second lens 3 reduces and forms an image of the crossover C1 as a crossover C2 at a position on the image plane side of the lens 3. The third lens 4 projects and images the crossover C2 on the drawing material 6 to generate the crossover C3.
[0009]
A diaphragm 7 is disposed along the optical axis of the electron beam. The diaphragm 7 has a role of blocking the electron beam deflected by the blanking deflector 5. In addition, a diaphragm 8 is provided in the second lens 3, and this diaphragm 8 is for limiting the electron beam. Further, a deflector 9 for deflecting the electron beam according to the drawing pattern is provided at the position of the third lens 4.
[0010]
A predetermined acceleration voltage or the like is applied to the electron gun 1 from an electron gun control power source 10. Further, a desired lens current is supplied from the lens power supply 11 to the first electronic lens 2, a desired lens current is supplied from the lens power supply 12 to the second electronic lens 3, and the third electronic lens 4 is supplied to the third electronic lens 4. A desired lens current is supplied from the lens power supply 13.
[0011]
A deflection signal based on the drawing data from the drawing pattern processing unit 14 is supplied to the deflector 9 via the DA converter 15 and the amplifier 16. A blanking signal is supplied from the drawing pattern processing unit 14 to the blanking deflector 5 via the amplifier 17. Drawing data is supplied from the computer 18 to the drawing pattern processing unit 14. The computer 18 controls the electron gun control power supply 10, the lens power supply 11 of the first lens 2, the lens power supply 12 of the second lens 3, and the lens power supply 13 of the third lens 4.
[0012]
The drawing material 6 is placed on a moving stage 19, and the moving stage 19 is driven by a stage driving power source 20 controlled by a computer 18. The operation of such a configuration will be described next.
[0013]
The position data and dimension data of the electron beam irradiated on the drawing material 6 are written and stored in the computer 18 in advance. Data stored in the computer 18 is supplied to the drawing pattern processing unit 14 and processed. Here, the contents of this processing will be described with reference to FIG.
[0014]
The data stored in the computer 18 is all the patterns included in the region to be a semiconductor element, but in order to simplify the description, as shown in FIG. A description will be given by taking an example of drawing when patterns P1 to P4 exist. Since the semiconductor element region R is usually larger than the drawing field, the drawing data is stored in the computer 18 as information for each field divided into a plurality of fields F11 to F44.
[0015]
The patterns P1 and P3 straddling the field F22 are divided at the field boundaries and become patterns P13 and P33 as shown in FIG. The pattern P2 that does not straddle the drawing field is not divided at the field boundary and remains the pattern P2. Taking the pattern P2 as an example, the position is expressed by the positions X0, Y0 from the field origin corner, the length W, and the height H. The drawing pattern processing unit 14 is shown in FIG. As shown, it is divided into a range where the electron beam can be scanned (hereinafter referred to as a beam scanning range). This beam scanning range is indicated as r in FIG.
[0016]
Each of the divided patterns is stored as data with information on the position from the origin X0, Y0 of the pattern before division and the beam scanning range. The ranges FW and FH in which the beam can be scanned are maximum scanning ranges determined by the capability of the deflection control system, as shown in FIG. However, the beam scanning range may be less than the maximum scanning range, as shown in FIG. 2E, depending on the size of the divided pattern. In FIG. 2D, S represents the beam scanning start position, and E represents the beam scanning end position.
[0017]
The drawing pattern processing unit 14 generates a scanning signal for performing a filling scan with a beam based on the position signal corresponding to the drawing position designated by the drawing pattern and the drawing pattern dimension. The address signal indicating the drawing position and the scanning signal for filling are supplied to the DA converter 15 as a pulse signal.
[0018]
Immediately after the drawing position is converted into an analog signal, the scanning signal generates a pulse signal having the number of beam increments corresponding to the scanning length FW (the number obtained by dividing the scanning length by the scanning increment) at the specified frequency, and sets the scanning height to FH. Up to the corresponding number (the number obtained by dividing the scanning height by the scanning increment) is given to the DA converter 15. The drawing position and the scanning signal converted into analog by the DA converter 15 are amplified by the amplifier 16 to a voltage necessary for beam scanning deflection and supplied to the deflector 9.
[0019]
In addition to the division calculation, the drawing pattern processing unit 14 generates a blanking signal for blocking the irradiation of the electron beam to the material 6 during the positioning of the drawing pattern to be drawn next after the drawing pattern is finished. The blanking signal is supplied to the amplifier 17 to generate a beam cutoff voltage, and this voltage is supplied to the blanking deflector 5. This cutoff voltage is required to respond at high speed.
[0020]
In the blanking control, the electron optical system is operated so that an object point image C1 corresponding to the beam image on the material surface is formed at the center (deflection main surface) of the one-stage deflector 5, and this blanking deflection is performed. A diaphragm 7 having an opening is provided immediately below the vessel 5 so as to receive the deflected beam outside the opening. Note that the opening is not subjected to blanking deflection, that is, a passage through which the beam passes when the material 6 is irradiated with the beam.
[0021]
[Problems to be solved by the invention]
In the above-described configuration, the beam passing through the opening has a spread A. Therefore, in order to block the beam, the size of the opening must be larger than the size of the beam. Also, the size of the opening must be relatively large in order to facilitate beam axis alignment. For these reasons, the deflection voltage for blocking the beam becomes a high voltage, and the response speed becomes long.
[0022]
As a method for shortening the response time, a deflection system shown in FIG. 3 is used. This method is basically based on the blanking deflector having a two-stage configuration of an upper deflector 22 and a lower deflector 23. And this intermediate (virtual deflection main surface position of the two-stage deflection system, this position is not necessarily intermediate because the position of the virtual deflection main surface is determined by the selection of the dimensional difference between the upper and lower deflectors and the supply voltage difference. An electron optical system that forms an object point image C1 corresponding to the beam image on the material surface is used at a position (not necessary), and the beam is positioned in the middle of the two-stage blanking deflector (object point image position). This is a method of disposing the blocking diaphragm 24.
[0023]
In this method, when the beam EB is blanked, it is deflected like EB ′ and is blocked by the diaphragm 24. C1b is a crossover position moved by deflection.
[0024]
The beam imaged at the position of the beam blocking diaphragm 24 is several μm or less. However, the size of the opening of the beam blocking diaphragm 24 must be increased to some extent in order to align the beam axis. However, the entire deflection voltage is required before the beam is cut off.
[0025]
FIG. 4 shows this state. When the beam axis EB is at the center of the opening d2 of the beam cutoff diaphragm 24 as shown in FIG. 4A, the distance (Lbk is half the distance Lbk determined by the deflection voltage). When the beam axis EB is at the end of the opening d2 of the beam blocking diaphragm 24 as shown in FIG. 4B, the distance Lbk determined by the deflection voltage is cut. The beam is blocked by deflecting the distance of. In other words, the former is half of the total deflection voltage, the latter is deflected by the total deflection voltage, and the former has a shorter response time until cutoff.
[0026]
Thus, even in a configuration in which it can be confirmed that the beam axis is always located around the opening d2 of the beam blocking diaphragm 24, the deflection voltage required for blocking the beam needs to be half of the maximum output. The deflection voltage requires a higher voltage as the acceleration voltage of the drawing apparatus becomes higher, and the response speed becomes longer as the deflection voltage becomes higher. For this reason, when the beam scanning frequency becomes very high, the beam at the pattern drawing start position (S in FIG. 2D) and the end position (E in FIG. 2D) is irradiated more than a predetermined time. A phenomenon occurs, which causes a reduction in edge resolution of a drawn pattern.
[0027]
The present invention has been made in view of these points, and its purpose is to make the beam reach the cutoff diaphragm edge at a distance far smaller than the total deflection amplitude during beam cutoff deflection, and to greatly increase the time until beam cutoff. An electron beam writing apparatus capable of improving the edge resolution of the drawing pattern by shortening the length of the drawing pattern is realized.
[0028]
[Means for Solving the Problems]
The electron beam writing apparatus according to the first invention focuses the electron beam and irradiates the drawing material, deflects the electron beam according to the drawing pattern, and draws a desired pattern on the drawing material. The electron beam writing apparatus includes a blanking deflector, and an adjustment mechanism for adjusting the position of the aperture opening provided with a stop for blocking or turning on the electron beam deflected by the blanking deflector. It is characterized by that.
[0029]
In the first invention, the position of the aperture of the diaphragm is adjusted, and the axial position of the electron beam is positioned near the edge of the aperture of the diaphragm.
According to a second aspect of the present invention, there is provided an electron beam drawing apparatus according to the first aspect, wherein the blanking deflector has a two-stage configuration and a diaphragm is disposed between the two-stage deflectors.
[0030]
An electron beam blanking method in an electron beam writing apparatus according to a third aspect of the present invention focuses an electron beam and irradiates the material to be drawn, and deflects the electron beam in accordance with the drawing pattern so as to be desired on the material to be drawn. In the electron beam drawing apparatus, the position of the aperture portion of the aperture is drawn with a blanking deflector and an aperture that blocks the electron beam deflected by the blanking deflector. The beam axis is positioned in the vicinity of the edge on the beam blocking deflection direction side in the opening , and blanking of the electron beam is performed in this state.
[0031]
An electron beam blanking method in an electron beam drawing apparatus according to a fourth aspect of the present invention is the electron beam blanking method according to the third aspect of the present invention, wherein the electron beam is scanned in a planar manner across the aperture edge of the stop that blocks the electron beam, The electron beam passing near the edge is displayed as a bright shadow on the monitor, the position of the aperture of the diaphragm is adjusted, and the beam axis is positioned in the vicinity of the edge on the beam cutoff deflection side in the aperture. It is characterized by electron beam blanking.
[0032]
An electron beam blanking method in an electron beam drawing apparatus according to a fifth aspect of the present invention is the electron beam blanking method according to the third aspect of the present invention, wherein the electron beam is scanned linearly across the aperture edge of the stop for blocking the electron beam, The signal waveform of the electron beam passing through the aperture is displayed, the position of the aperture of the diaphragm is adjusted, the beam axis is positioned near the edge of the aperture on the beam cutoff deflection side, and in this state the electron beam It is characterized by the fact that blanking is performed.
[0033]
An electron beam blanking method in an electron beam drawing apparatus according to a sixth aspect of the present invention is the method according to the third aspect, wherein the amount of current of the electron beam passing through the aperture of the aperture that blocks the electron beam is measured and the aperture of the aperture is measured. adjust the position, the beam axis is positioned near the edge of the beam blocking deflection direction in the opening, it is characterized in that to perform the blanking of the electron beam in this state.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 5 is a diagram showing an example of an electron beam drawing apparatus according to the present invention. The same or similar components as those in the conventional apparatus of FIGS. 1 and 4 are given the same reference numerals, and detailed description thereof is omitted.
[0035]
In FIG. 5, blanking deflectors 22 and 23 for blocking and feeding the beam on the drawing material 6 constitute a two-stage deflection system, and deflect the beam in the same direction. By selecting the structural dimensions of the upper and lower electrodes of the two deflectors 22 and 23 and the supply voltage ratio, the virtual deflection fixed point of the two-stage deflection system can be determined at an arbitrary position.
[0036]
Here, an imaging system that takes the middle of the two-stage deflector as a virtual deflection main surface of the two-stage deflection system and forms an object point image C1 corresponding to the beam image on the material surface at this position, and a beam blocking diaphragm 24. Is arranged. The position of the opening provided in the diaphragm 24 can be adjusted by the adjusting mechanism 25. The blanking signal from the pattern processing unit 14 is supplied to the upper deflector 22 via the amplifier 17a, and is supplied to the lower deflector 23 via the amplifier 17b.
[0037]
Since the beam imaged at the position of the beam blocking diaphragm 24 is several μm or less, the size of the opening of the blocking diaphragm 24 must be larger than this, and therefore several tens of μm (for example, 50 μm). Use the opening. FIG. 6 shows the positional relationship between the opening and the beam. FIG. 6A shows a configuration example of the opening of the beam blocking diaphragm 24. A plurality of openings d2 having the same dimensions are provided (or a single opening), and an opening d1 having a large dimension different from the openings d2 is also provided.
[0038]
The reason why a plurality of openings d2 are provided is that they are switched and used when the beam receiving stop 24 is contaminated and becomes unusable due to contamination. The large-sized opening d1 is used to easily pass the beam when performing beam axis alignment. The opening adjusting mechanism 25 also has a moving mechanism for adjusting the horizontal position.
[0039]
After alignment of the beam axis, the position of the beam blocking diaphragm 24 is switched to the position of the opening d2 by the opening adjustment mechanism 25. However, since the opening d2 is small, the beam cannot be easily passed. This adjustment method will be described with reference to FIG. Since the components having the same numbers as those in FIG. 1 have the same functions, detailed description thereof will be omitted. Above the two-stage blanking deflection system, a deflector 26 (shown as an electromagnetic deflector in the figure but may be an electrostatic deflector) for scanning a beam in a two-dimensional plane is provided. A scanning signal is supplied from a scanning signal generator 27 to the unit 26. As a result, the opening of the beam blocking diaphragm 24 is scanned by the beam.
[0040]
The beam passes through the opening d2, and the passing beam is detected by the beam receiving plate 28 inserted on the beam axis (during this adjustment only) and converted into a voltage signal by the converter 29. This voltage signal is supplied as a luminance signal to the monitor 30 to which the scanning signal from the scanning signal generator 27 is supplied. As a result, when the scanning signal amplitude of the scanning signal generator 27 is increased, the opening shape appears on the monitor 30 as a bright shadow (a circle when the opening is circular) AP1.
[0041]
The horizontal position adjusting mechanism of the opening adjusting mechanism 25 is adjusted so that the edge of the bright shadow is positioned at the center of the screen of the monitor 30. When the scanning signal amplitude of the scanning signal generator 27 is reduced, the brightness on the monitor 30 increases and a part of the brightness appears on the monitor screen as AP2. The opening position adjustment mechanism is adjusted so that the edge of the bright shadow is positioned at the center of the screen of the monitor 30. The difference between the center of the monitor and the position shifted in the horizontal direction corresponds to Lon in FIG. When this difference is large, it becomes LON shown in FIG. 6B, and the time until the beam is cut off becomes long.
[0042]
Another adjustment method of the alignment of the opening d2 after the beam axis alignment will be described with reference to FIG. This method is an example that does not require the addition of a deflector for adjustment. The scanning signal generator 32 generates a sawtooth wave or triangular wave line scanning signal. The switch SW is a switch for switching a signal to be supplied to the deflector 22 on the upper side of the beam blocking diaphragm 24 between a line scanning signal from the scanning signal generator 32 and a beam blocking signal from the amplifier 17a.
[0043]
The line scanning signal from the scanning signal generator 32 scans the vicinity of the opening position of the beam blocking diaphragm 24 with a beam. The beam that has passed through the opening d2 is detected by the beam receiving plate 28 and converted into a voltage signal by the voltage converter 29. A scanning signal from the scanning signal generator 32 is supplied to one input (not shown) of the monitor (oscilloscope) 33, the waveform of the line scanning signal is displayed on the monitor 33, and the other input (not shown) is displayed. The voltage signal detected by the beam receiving plate 28 is supplied, and the detection signal waveform is displayed on the monitor.
[0044]
When the line scanning signal amplitude of the scanning signal generator 32 is increased, the beam is blocked except at the opening, so that a pulsed waveform PL is obtained on the monitor. A portion that is blocked other than the opening is Io, and a portion that passes through the opening is Ib. The position of the diaphragm 24 is adjusted by the horizontal position adjusting mechanism 25 so that the position of the falling portion PD of the pulse waveform approaches the scanning start position Ss of the line scanning signal.
[0045]
It is possible to adjust the horizontal position adjustment mechanism so that the line scanning signal amplitude of the scanning signal generator 32 is reduced and the falling part PD position of the pulse waveform on the monitor 33 approaches the line scanning start position Ss. The difference between the falling portion PD position of the pulse waveform and the line scanning start position Ss corresponds to Lon in FIG. When this difference is large, it becomes as shown in FIG. 6B, and the time until the beam is cut off becomes long. In the case where no line scanning signal is given, the center of the monitor is the beam position and the line scanning direction is the beam blocking deflection direction.
[0046]
A further method of adjusting the alignment of the beam cutoff aperture after beam alignment is a method that does not require beam scanning. The beam that has passed through the opening d2 is detected by the beam receiving plate 28. While monitoring the detection ammeter, adjust the horizontal position adjustment mechanism to the position where the current value is about to disappear. In this state, the beam is positioned at the edge of the beam blocking opening d2. From this position, the edge is moved slightly (several tens of μm) by the horizontal position adjusting mechanism in the beam blocking deflection direction. Since it is not known whether this edge is the edge on the beam blocking deflection direction side or the opposite edge, the horizontal position adjusting mechanism is moved in the beam blocking deflection direction, and this is confirmed by the detection ammeter indicating the current value.
[0047]
Whether the edge is orthogonal to the beam cutoff deflection direction is determined by moving the horizontal position adjustment mechanism in a direction orthogonal to the beam cutoff deflection direction, and the indicated value of the detection ammeter is within this minute change range. Is adjusted so that it is at the center position of the moving mechanism range that gives the position, and then the beam blocking deflection direction of the horizontal position adjusting mechanism is adjusted to determine the position. In this method, it goes without saying that the biaxial movement direction of the horizontal position adjusting mechanism is parallel to and orthogonal to the beam blocking deflection direction.
[0048]
As described in detail above, the beam blocking time on the drawing material is set to several nsec by adjusting the position of the edge of the beam receiving blocking opening very close to the beam starting to be deflected by the beam blocking deflection. Is possible. This content will be described in more detail with reference to FIG.
[0049]
FIG. 9A shows a case where the position of the blocking opening is not adjusted, and the position where the beam normally passes (the beam axis position during drawing) is far from the blocking opening edge, and the beam blocking opening is from the start of beam blocking deflection. Therefore, it takes time tda to return to a position where the beam normally passes. If the time corresponding to the total deflection distance Lbk is 15 nsec, about 10 nsec is expected, and in some cases, it may take 15 nsec.
[0050]
FIG. 9B shows a case where the position of the blocking aperture is adjusted. The position from where the beam normally passes (the beam axis position during drawing) is close to the edge of the blocking aperture. Since the distance Lonb to the edge of the part is short, the time tdb until the beam completely returns to the normal passing position is short. If the time corresponding to the total deflection distance Lbk is 15 nsec, it can be about 2 nsec.
[0051]
For example, the beam stop time on the scan increment when the beam scan is a pattern-filled scan at a cycle of 100 MHz is 10 nsec, and the beam cutoff time must be shorter than this. If the beam blocking time is long, an increase in beam irradiation time (twice as much as one increment in the above example) occurs at the scanning start position S or the scanning end position E, which causes a reduction in the edge resolution of the drawing pattern. It has become. If the beam blocking time is shorter than the drawing increment stop time of 10 nsec, the edge resolution can be prevented from being lowered.
[0052]
Although the embodiment of the present invention has been described in detail above, the present invention is not limited to this embodiment. For example, although the blanking deflector has a two-stage configuration, the present invention can be applied to a case where a single-stage deflector is used. Further, the shape of the electron beam passage opening provided in the stop may be circular or rectangular.
[0053]
【The invention's effect】
As described above, in the first and second inventions, the configuration is such that the position of the aperture of the aperture is adjusted and the axial position of the electron beam is positioned near the edge of the aperture of the aperture. The beam can reach the cutoff diaphragm edge at a distance much smaller than the total deflection amplitude at the time of deflection, and the time to beam cutoff can be greatly shortened. As a result, the edge resolution of the drawing pattern can be remarkably improved, and high-precision drawing is achieved.
[0054]
In the third to sixth inventions, the position of the aperture of the diaphragm is adjusted, the beam axis is positioned in the vicinity of the edge of the aperture on the beam blocking deflection direction side, and the electron beam is blanked in this state. Therefore, the beam can reach the cutoff aperture edge at a distance much smaller than the total deflection amplitude at the time of electron beam cutoff deflection, and the time to beam cutoff can be greatly shortened. As a result, the edge resolution of the drawing pattern can be remarkably improved, and high-precision drawing is achieved.
[Brief description of the drawings]
FIG. 1 shows a conventional electron beam drawing apparatus.
FIG. 2 is a diagram for explaining a drawing method using a spot beam;
FIG. 3 is a diagram showing a state of beam blanking by a two-stage deflector.
FIG. 4 is a diagram showing a state of beam movement by a blanking operation.
FIG. 5 is a diagram showing an electron beam drawing apparatus according to the present invention.
6 is a diagram showing the shape of a diaphragm used in the apparatus of FIG. 5 and how the beam moves during blanking.
FIG. 7 is a diagram illustrating an example of a configuration for adjusting a diaphragm position.
FIG. 8 is a diagram illustrating an example of a configuration for adjusting a diaphragm position.
FIG. 9 is a diagram showing how blanking time is shortened.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Electron gun 2, 3, 4 Electron lens 6 Drawing material 9 Deflector 10 Electron gun control power supply 11, 12, 13 Lens power supply 14 Drawing pattern processing unit 15 DA converter 16, 17 Amplifier 18 Computer 22, 23 Blanking deflection 24 diaphragm

Claims (6)

A blanking deflector in an electron beam drawing apparatus that focuses an electron beam and irradiates a drawing material, deflects the electron beam according to a drawing pattern, and draws a desired pattern on the drawing material. And an adjusting mechanism that adjusts the position of the aperture of the aperture provided with an aperture for blocking or turning on the electron beam deflected by the blanking deflector. 2. The electron beam lithography apparatus according to claim 1, wherein the blanking deflector has a two-stage configuration, and a diaphragm is disposed in the middle of the two-stage deflector. Focusing and irradiating the material to be drawn with the electron beam, deflecting the electron beam according to the drawing pattern, drawing a desired pattern on the drawing material, and deflecting with a blanking deflector and a blanking deflector In an electron beam drawing apparatus in which an electron beam is blanked by a diaphragm that blocks the generated electron beam, the position of the aperture of the diaphragm is adjusted, and the beam axis is an edge on the beam blocking deflection direction side in the opening It is located in the vicinity, blanking method electrostatic flatter over arm which to perform the blanking of the electron beam in this state. The electron beam is scanned in a plane across the aperture edge of the aperture that blocks the electron beam, and the electron beam passing near the edge of the aperture is displayed as a bright shadow on the monitor, and the aperture aperture position is adjusted. and, the beam axis is positioned near the edge of the beam blocking deflection direction in the opening, the blanking process of the electron beam according to claim 3, wherein which to perform the blanking of the electron beam in this state. Scan the electron beam linearly across the aperture edge of the aperture that blocks the electron beam, display the signal waveform of the electron beam passing through the aperture on the waveform monitor, adjust the position of the aperture of the aperture, the beam axis is positioned near the edge of the beam blocking deflection direction in the opening, the blanking process of the electron beam according to claim 3, wherein which to perform the blanking of the electron beam in this state. Measure the amount of current of the electron beam that passes through the aperture of the aperture that blocks the electron beam, adjust the position of the aperture of the aperture, and position the beam axis near the edge of the aperture on the beam cutoff deflection direction side. , blanking method of an electron beam according to claim 3, wherein which to perform the blanking of the electron beam in this state.

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