CN117373885A - Method and system for measuring size of Gaussian distribution electron beam spot - Google Patents
Method and system for measuring size of Gaussian distribution electron beam spot Download PDFInfo
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Abstract
The invention discloses a measuring method of Gaussian distribution electron beam spot size, comprising the following steps: scanning the electron beam with a straight line path to a knife edge, and detecting an electron beam state signal and an electron beam scanning distance in the scanning process; the electron beam state signal includes scattered electron signal intensity or electron beam power through the knife edge; wherein the straight line path and the arrangement direction of the knife edge form an included angle theta, and the included angle theta ranges from 5 degrees to 30 degrees; and obtaining the beam spot diameter of the electron beam according to the electron beam state signal and the electron beam scanning distance. The invention also discloses a measuring system of the Gaussian distribution electron beam spot size. Compared with the existing scanning method, the measuring method can increase the length of a scanning path, reduce the influence of the electronic accumulation effect at the edge of the knife edge, reduce the measuring error, has low cost, simple steps and wide applicability, and can be used for measuring the electron beam spots of 10nm and below.
Description
Technical Field
The invention relates to the field of electron beam detection, in particular to a method and a system for measuring the size of a Gaussian distribution electron beam spot.
Background
Gaussian distributed electron beams are widely used in many electron beam equipment fields, such as electron microscopes, electron beam exposure machines, and the like. In such devices, electron beams are often the implementation means of the main functions, such as electron beam bombardment to the surface of the material to be detected by using an electron microscope, and detection of the feedback electronic signals is performed, so that the smaller the size of the beam spot of the electron beam is, the smaller the area of the electronic signals can be controlled, and the higher the detection accuracy is. The electron beam exposure machine uses an electron beam as a "pen" for drawing a drawing, and the smaller the beam spot size is, the smaller the minimum drawing size can be achieved.
Since electron beams are the main functional means of many electron beam devices, the pursuit of the reduction of the beam spot size becomes the development direction of many advanced devices, and after the electron beams emitted by the electron gun are focused by the electromagnetic lens on the relevant device, the beam spot size of the electron beams in the interface direction has been reduced to an extremely tiny category, often reaching below 10nm, even reaching the order of 3nm (calculated value).
At present, some scanning electron microscopes can calculate the beam spot size by scanning the edges of a flat pattern to detect the imaging signal intensity of the detector, but the methods have larger errors in electron beam measurement facing diameters of 10nm and below, and the extremely high-precision knife edge device has higher cost and quite high installation requirements, and cannot meet the requirements of rapid and precise measurement.
Specifically, the intensity distribution of the gaussian distributed electron beam in the cross-sectional direction is defined as shown in formula (1):
wherein I is (r) For electron beam current intensity, I 0 For maximum intensity of electron beam, P 0 The total power of the electron beam is omega, the radius of the electron beam spot, and r is the distance between the knife edge and the center of the electron beam spot. Beam intensity of Gaussian distribution electron beam such asShown in fig. 1.
As shown in fig. 2, the current measurement method of beam spot size of gaussian distribution generally adopts a knife edge method, that is, a flat straight boundary material is used to make an electron beam sweep across a straight boundary in a direction perpendicular to the straight boundary, and the beam spot size is calculated by measuring the variation of beam current intensity and the scanning distance during the process of sweeping across the straight boundary.
In the above measurement method, the beam intensity of the electron beam can be measured by the faraday cup, so that the beam spot diameter of the electron beam is usually obtained by adding a knife edge device to the opening of the faraday cup and detecting the relationship between the beam scanning position and the beam intensity of the electron beam when the knife edge is scanned. At present, as shown in fig. 3, a conventional faraday cup knife-edge device structure is shown, an electromagnetic lens 1 is arranged on two sides of an electron beam 3, the electron beam 3 enters a faraday cup 4 through a knife-edge device 2, the faraday cup 4 is a beam receiving device, and then the beam intensity is detected through a signal processing system 5.
However, the existing measuring method has larger error in the electron beam measurement of the diameter of 10nm and below, and the extremely high-precision knife edge device has higher cost and quite high installation requirement, and cannot meet the requirement of quick and accurate measurement.
Disclosure of Invention
The invention aims to solve the technical problem of overcoming the defects of the prior art and providing a measuring method and a measuring system for the size of a Gaussian distribution electron beam spot, which have the advantages of high detection precision, simple steps and wide applicability.
In order to solve the technical problems, the invention adopts the following technical scheme:
a method for measuring the size of a Gaussian distribution electron beam spot comprises the following steps:
s1, scanning an electron beam with a straight line path to a knife edge, and detecting an electron beam state signal and an electron beam scanning distance in the scanning process; the electron beam state signal comprises scattered electron signal intensity or electron beam power transmitted through the knife edge; wherein the straight line path and the arrangement direction of the knife edge form an included angle theta, and the included angle theta ranges from 5 degrees to 30 degrees;
s2, obtaining the beam spot diameter of the electron beam according to the electron beam state signal and the electron beam scanning distance.
Preferably, in step S1, two different points on the knife edge are scanned by using an electron beam to determine a straight line where the knife edge is located, so as to determine an included angle θ between the straight line path and the straight line where the knife edge is located.
Preferably, in step S1, when the electron beam status signal is the scattered electron signal intensity, detecting that the scattered electron signal intensity is a preset percentage of the maximum scattered electron signal intensity twice, and the distance L passed by the electron beam scanning; wherein the maximum scattered electron signal intensity is the scattered electron signal intensity when the electron beam is completely located on the wafer;
and in step S2, the beam spot diameter d of the electron beam is obtained by the following formula:
d＝ALsinθ；
wherein A is the proportionality coefficient of the distance L passed by the electron beam scanning under different electron beam powers and the electron beam diameter d.
Preferably, the preset percentage is 50% -70%.
Preferably, in step S1, when the electron beam state signal is the electron beam power transmitted through the knife edge, detecting that the electron beam power is a first percentage and a second percentage of the maximum electron beam power, respectively, corresponding to the distance L through which the electron beam scans; the second percentage is greater than the first percentage; the maximum electron beam power is the power when the electron beam is not shielded by the knife edge;
and in step S2, the beam spot diameter d of the electron beam is obtained by the following formula:
d＝ALsinθ；
wherein A is the proportionality coefficient of the distance L passed by the electron beam scanning under different electron beam powers and the electron beam diameter d.
Preferably, the first percentage is 10% -20% and the second percentage is 80% -90%.
Preferably, in step S1: the kerf is made by dicing a wafer and has an atomic level flatness.
Preferably, the material of the wafer is silicon/gallium arsenide.
The invention also discloses a computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, performs the steps of the method as described above.
The invention also discloses a measuring system of the Gaussian distribution electron beam spot size, which comprises a memory and a processor which are connected with each other, wherein the memory stores a computer program which executes the steps of the method when being executed by the processor.
Compared with the prior art, the invention has the advantages that:
1. the measuring method adopted by the invention has the advantages that the electron beam scans the linear knife edge of the wafer material in the linear path, the linear path and the arrangement direction of the knife edge form an included angle theta, the steps are simple, compared with the original scanning method adopting the linear knife edge vertical to the wafer material, the length of the scanning path can be increased, the influence of the electron accumulation effect of the edge of the knife edge is reduced, thereby reducing the measuring error, and being applicable to the measurement of the beam spot size of the ultra-fine (10 nm and below).
2. The measuring method adopted by the invention can be directly applied to the existing measuring equipment, and can measure the size of the electron beam spot through simple and easily obtained wafer materials under the condition of not changing the basic structure of the existing electron beam equipment, and has the advantages of low cost, simple steps and wide applicability.
Drawings
Fig. 1 is a schematic view of intensity distribution of a gaussian distributed electron beam in a cross-sectional direction.
Fig. 2 is a schematic diagram of a prior art knife edge measurement technique.
Fig. 3 is a schematic structural diagram of a conventional electron beam current intensity measuring device with a faraday cup.
Fig. 4 is a flow chart of a method for measuring beam spot size of a gaussian distributed electron beam employed in an embodiment of the present invention.
Fig. 5 is a schematic structural view of a measuring apparatus used in the measuring method of the present invention.
Fig. 6 is a schematic view of an electron beam scanning a knife edge at an angle to the knife edge in an embodiment of the invention.
Fig. 7 is a graph showing the intensity of an electron signal obtained by scanning an electron beam at an angle to a knife edge and scanning the knife edge perpendicular to the direction of the knife edge, respectively, in an embodiment of the present invention.
Fig. 8 is a schematic diagram of determining a straight line where a knife edge is located in an embodiment of the present invention.
FIG. 9 is a graph of the relationship between beam power, scattered electron signal intensity, and beam spot radius, diameter for a Gaussian distribution electron beam transmitted through a knife edge.
The attached drawings are used for identifying and describing:
1. an electromagnetic lens; 2. a knife edge device; 3. electron beam current; 4. a Faraday cup; 5. a signal processing system; 6. an electron gun; 7. an electron optical column; 8. a focus deflection device; 9. a work table; 10. a detection module; 11. newly cut wafers.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the invention. All other embodiments, which can be made by one of ordinary skill in the art without inventive effort, are intended to be within the scope of the present invention, based on the embodiments herein.
In the description of the present invention, it should be noted that, the terms "center," "upper," "lower," "horizontal," "inner," "outer," "top," "bottom," and the like indicate an orientation or a positional relationship based on that shown in the drawings, and are merely for convenience of description and to simplify the description, rather than indicate or imply that the apparatus or elements being referred to must have a specific orientation, be constructed and operate in a specific orientation, and thus should not be construed as limiting the present invention.
Fig. 4 shows a method for measuring beam spot size of a gaussian distributed electron beam according to an embodiment of the present invention, including the steps of:
s1, scanning an electron beam with a straight line path to a knife edge, and detecting an electron beam state signal and an electron beam scanning distance in the scanning process; the electron beam state signal includes scattered electron signal intensity or electron beam power through the knife edge; wherein the straight line path and the arrangement direction of the knife edge form an included angle theta, and the included angle theta ranges from 5 degrees to 30 degrees;
s2, obtaining the beam spot diameter of the electron beam according to the electron beam state signal and the electron beam scanning distance.
The measuring method adopted by the invention aims at the situations of larger error and inaccurate measurement when the knife edge method is adopted to measure the electron beam with the diameter of 10nm or less at present, when the electron beam scans the knife edge in a straight line path, the electron beam scans the straight line knife edge of the wafer material in the straight line path forming an included angle theta with the arrangement direction of the knife edge, compared with the original scanning method adopting the straight line knife edge perpendicular to the wafer material, the length of the scanning path can be increased, the influence of the electron accumulation effect at the edge of the knife edge is reduced, thereby reducing the measuring error, and being applicable to the measurement of the size of the ultra-fine (10 nm or less) electron beam spots; the measuring method adopted by the invention can be directly applied to the existing measuring equipment, and has low cost, simple steps and wide applicability under the condition of not changing the basic structure of the existing electron beam equipment.
Specifically, as shown in fig. 5, the measuring apparatus for realizing the measuring method of the present invention includes an electron gun 11, an electron-optical column 12, a focus deflection device 13, a work stage 14, a detection module 15, a newly cut wafer 16. An electron gun 11 is mounted on top of the electron optical column 12 for emitting an electron beam; the focusing deflection devices 13 are installed at both sides of the electron optical column 12 for performing deflection control on the electron beam; the workpiece stage 14 is used for placing wafer material 16; the detection module 15 is used for detecting the signal intensity of the electron beam; the position of the wafer material 16 corresponds to the position of the electron beam emitted by the electron gun 11. The detection module 15 may be configured as an electronic signal intensity detection module or an electronic beam power detection module according to the electronic signal intensity or the electronic beam power to be detected.
In the measuring method of the present invention, as shown in FIG. 6, the electron beam is scanned while controlling the direction of the beam spot movement of the electron beam to form an angle θ with the straight line edgeThe beam current can emit scattered electrons with different energy and dose according to different materials bombarded before and after passing through the knife edge. When the electron beam spot does not fall on the knife edge material at all, the intensity of the scattered electron signal collected at the moment is assumed to be I 1 When the electron beam spot is completely located on the knife edge material, the intensity of the scattered electron signal collected at the moment is assumed to be I 2 A significant dynamic curve of scattered electron signal intensity occurs during the passage of the electron beam spot through the knife edge.
Since the scattered electron signal intensity is the sum of the signal intensities obtained by exciting all electrons in the gaussian-distributed electron beam, the signal intensity variation curve obtained by sweeping the electron beam spot over the knife edge can be considered as the integral of the intensity distribution curve inside the gaussian-distributed electron beam spot, i.e. the curve obtained by sweeping the electron beam spot over the knife edge can be simply back-extrapolated to obtain the intensity distribution curve inside the beam spot.
The intensity distribution curve inside the gaussian distributed electron beam spot follows a gaussian distribution as shown in equation (2):
wherein I is (x,y) For electron beam current intensity, I 0 For maximum intensity of electron beam, P 0 The total power of the electron beam is omega, the radius of the electron beam spot is omega, and x and y are the position coordinates of the knife edge relative to the center of the electron beam spot.
Whereas the total power P of the electron beam 0 And can be determined by the formula (3):
the relation between the power P and the beam intensity I of the Gaussian distribution electron beam and the radius omega and the diameter d of the electron beam spot can be obtained through mathematical calculation, namely the beam spot diameter of the electron beam can be obtained through calculation of a formula through an electron beam state signal (scattered electron signal intensity or electron beam power penetrating through a knife edge) and an electron beam scanning distance.
One specific example is: according to the angle theta between the beam spot moving direction of the electron beam and the straight line knife edge, the relation between the scanning distance L and the beam spot diameter d is d=Lsin theta, if the electron beam scanning path is scanned at an included angle of 17.5 degrees with the knife edge, the diameter converted from the Gaussian Shu Ban curve measured by 17.5 degrees scanning can be multiplied by sin 17.5 degrees (about 0.301), and the actual Gaussian beam spot diameter can be obtained. If the electron beam scanning distance is 10nm, the actual electron beam spot diameter is 10nm×sin 17.5 deg. about 3nm. Because the diameter of the electron beam with the 3nm scale is too small, if a traditional vertical scanning mode is adopted, the measurement error is too large and can be influenced by the electron accumulation effect of the edge of the knife edge, and the test reliability is poor. By adopting the measuring method, under the condition of measuring by using the included angle of 17.5 degrees, the scanning distance of the electron beam can be prolonged to 10nm, and the signal curve which is difficult to characterize can be converted into a scale which can be easily characterized to a certain extent. As shown in fig. 7, the intensity distribution diagram of the electron beam spot obtained by the scanning measurement method of the present invention and the conventional vertical scanning method are respectively shown. It can be seen that the range of the characterization distance of the intensity distribution graph on the x-axis obtained by the measuring method is obviously larger than that obtained by the traditional method, that is, the measuring error of the measuring method is smaller and the accuracy is higher.
In this embodiment, in step S1, two different points on the knife edge are scanned by using an electron beam to determine the straight line where the knife edge is located, thereby determining the included angle θ between the straight line path and the straight line where the knife edge is located.
Specifically, as shown in fig. 8, before performing scanning measurement of the beam spot size of the electron beam, first, two positions at the upper and lower ends of the knife edge are scanned using the electron beam to determine the position of the knife edge; secondly, determining two points through twice scanning, so as to determine the straight line where the knife edge is located; finally, the included angle theta of the straight line path of the electron beam scanning relative to the knife edge can be determined through the straight line where the knife edge is located.
In the embodiment, in step S1, when the status signal of the electron beam is the scattered electron signal intensity, detecting that the scattered electron signal intensity is a preset percentage of the maximum scattered electron signal intensity twice, and the distance L passed by the electron beam scanning; the maximum scattered electron signal intensity is the scattered electron signal intensity when the electron beam is completely positioned on the wafer;
and in step S2, the beam spot diameter d of the electron beam is obtained by the following formula:
d＝ALsinθ(4)
wherein A is the proportionality coefficient of the distance L passed by the electron beam scanning under different electron beam powers and the electron beam diameter d.
In this embodiment, the preset percentage is 50% -70%.
The beam spot diameter of the electron beam can be ignored when scanning, because the scanning distance of the common electron beam equipment is often tens to hundreds of micrometers, and compared with the scanning distance, the beam spot diameter is small and can be ignored. However, when the electron beam is scanned near the knife edge, the scanning length L is in the same order of magnitude as the beam spot radius r, if the electron beam is scanned perpendicular to the knife edge, the scanning distance is equal to the beam spot diameter when the beam spot is scanned across the knife edge, when the electron beam is scanned at an angle with the knife edge, the scanning distance is multiplied by a trigonometric function value to be equal to the beam spot diameter, and when the electron beam is scanned across the knife edge, the scanning distance is not related to the beam spot radius.
One specific example is as follows: when the knife edge is positioned at the beam radius of the electron beam (r=ω), the electron beam intensityThat is, the electron beam intensity at this time is about 13.5% of the maximum electron beam intensity, and the beam spot diameter d of the electron beam is calculated by detecting the distance L through which the electron beam is scanned when the scattered electron signal intensities are respectively 13.5% of the maximum electron beam intensity, where d=lsinθ. Alternatively, when the knife edge is located at half the beam radius (r=ω/2), the beam intensity +.>I.e. the electron beam intensity at this time is about 60% of the maximum electron beam intensity, by detecting scatteringThe beam spot diameter d of the electron beam is calculated by the distance L through which the electron beam is scanned when the electron signal intensity is 60% of the maximum intensity of the electron beam, where d=2lsinθ.
In this embodiment, in step S1, when the electron beam state signal is the electron beam power transmitted through the knife edge, the detected electron beam power is the first percentage and the second percentage of the maximum electron beam power, respectively, corresponding to the distance L through which the electron beam scans; the second percentage is greater than the first percentage; the maximum electron beam power is the power when the electron beam is not blocked by the knife edge;
and in step S2, the beam spot diameter d of the electron beam is obtained by the following formula:
d＝ALsinθ(5)
wherein A is the proportionality coefficient of the distance L passed by the electron beam scanning under different electron beam powers and the electron beam diameter d.
Specifically, since the beam spot size is typically much smaller than the width of the blade along the y-axis, the width of the blade along the y-axis can be considered to be infinity, and in fig. 2, when the blade is located at the-x position, the formula (6) of the beam power passing through the edge of the blade is:
the total power P is taken up by P (x) obtained by the formula (3) and the formula (6) 0 The formula (7) of the percentage is:
taking x/ω and y/ω as integral variables, ω/x corresponding to P (x)% can be calculated according to formula (7), and a=ω/x is defined, where a is a proportionality coefficient of the distance L travelled by the electron beam at different beam powers and the beam diameter d. And multiplying x by the calculated A value to obtain the numerical value of the beam spot radius omega corresponding to the knife edge coordinate x. Because Gaussian beams have symmetry, when the power of the electron beam accounts for P (x)% and 1-P (x)% of the total power respectively, the distance L which the electron beam scans is corresponding to, and then the expression of the beam spot diameter of the electron beam is: d=al. According to the invention, the straight line path of the electron beam scanning and the arrangement direction of the knife edge form an included angle theta, and the final expression of the beam spot diameter can be obtained as follows: d=alsin θ. The specific determination manner of the value a can refer to the existing literature, and is not repeated herein.
In the actual measurement process, by recording the intensity change curve of the electron beam spot when scanning the knife edge and the power curve of the electron beam penetrating through the knife edge, the relation curve of the power, the intensity and the radius d of the electron beam can be obtained, as shown in fig. 9. It can be understood that by detecting the power of the power curve of the electron beam penetrating through the knife edge, the intensity curve can be reversely deduced, and then the beam spot diameter is measured according to the corresponding relation.
One specific example is: when a=ω/x=2, the electron beam power transmitted through the knife edge at this time is calculated to be the maximum electron beam power P 0 15.9% and 84.1% of (C). When the test is carried out, the electron beam is scanned by a straight line path, the straight line path forms an included angle theta with the arrangement direction of the knife edge, and the power and the scanning distance of the electron beam penetrating through the knife edge are detected in the scanning process. Recording the power of the electron beam as the maximum power P of the electron beam 0 The electron beam spot diameter d=2lsin θ at this time, when the electron beam is at 15.9% and 84.1% of the position where the electron beam is located, to obtain the distance L through which the electron beam is scanned.
It can be understood that, since the scanning direction of the electron beam in the measuring process is not perpendicular to the knife edge but is at a certain angle, the actual scanning distance needs to be multiplied by a trigonometric function of the angle to be converted into the moving distance perpendicular to the knife edge direction, so that the distance passing through the knife edge is prolonged by scanning at a certain angle, and the beam spot diameter of the electron beam can be equivalently considered to be widened, so that the beam spot measuring error under the ultra-fine scale (below 10 nm) can be reduced.
In this embodiment, the first percentage is 10% -20% and the second percentage is 80% -90%. It will be appreciated that the detection of the electron beam power requires the use of a device such as a laser power meter, the measurement error of which is related to the selected measurement point, and therefore the selection of a first percentage of 10% to 20% and a second percentage of 80% to 90% results in a more accurate diameter of the resulting electron beam spot.
In this embodiment, in step S1: the kerf is made by dicing the wafer and has an atomic level flatness. Wherein the material of the wafer is silicon/gallium arsenide and other materials. It can be understood that, because the silicon/gallium arsenide wafer is a single crystal, the wafer can be broken in order along the crystal direction in the cutting process, and the local flatness of the formed section can reach the atomic/molecular level, so that the straight line knife edge formed after cutting is relatively flat, and the method has an important effect on reducing errors in the subsequent measuring process.
Embodiments of the present invention also provide a computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, performs the steps of the measurement method as described above. The embodiment of the invention also provides a measuring system for the size of the beam spot of the Gaussian distribution electron beam, comprising a memory and a processor which are connected with each other, wherein the memory is stored with a computer program which, when being run by the processor, performs the steps of the measuring method as described above. The medium and the system of the invention correspond to the method and have the advantages of the method.
While the invention has been described with reference to preferred embodiments, it is not intended to be limiting. Many possible variations and modifications of the disclosed technology can be made by anyone skilled in the art, or equivalent embodiments with equivalent variations can be made, without departing from the scope of the invention. Therefore, any simple modification, equivalent variation and modification of the above embodiments according to the technical substance of the present invention shall fall within the scope of the technical solution of the present invention.
Claims (10)
1. The method for measuring the size of the beam spot of the Gaussian distribution electron beam is characterized by comprising the following steps:
s1, scanning an electron beam with a straight line path to a knife edge, and detecting an electron beam state signal and an electron beam scanning distance in the scanning process; the electron beam state signal comprises scattered electron signal intensity or electron beam power transmitted through the knife edge; wherein the straight line path and the arrangement direction of the knife edge form an included angle theta, and the included angle theta ranges from 5 degrees to 30 degrees;
s2, obtaining the beam spot diameter of the electron beam according to the electron beam state signal and the electron beam scanning distance.
2. The method for measuring the size of a gaussian distributed electron beam spot according to claim 1, wherein: in step S1, two different points on the knife edge are scanned by using an electron beam to determine a straight line where the knife edge is located, so as to determine an included angle θ between the straight line path and the straight line where the knife edge is located.
3. The method for measuring the size of a gaussian distributed electron beam spot according to claim 1, wherein: in step S1, when the status signal of the electron beam is the scattered electron signal intensity, detecting that the scattered electron signal intensity is a preset percentage of the maximum scattered electron signal intensity twice, and the distance L passed by the electron beam scanning; wherein the maximum scattered electron signal intensity is the scattered electron signal intensity when the electron beam is completely located on the wafer;
and in step S2, the beam spot diameter d of the electron beam is obtained by the following formula:
d＝ALsinθ；
wherein A is the proportionality coefficient of the distance L passed by the electron beam scanning under different electron beam powers and the electron beam diameter d.
4. A method of measuring gaussian distributed electron beam spot size according to claim 3, characterized in that: the preset percentage is 50% -70%.
5. The method for measuring the size of a gaussian distributed electron beam spot according to claim 1 or 2, characterized in that: in step S1, when the electron beam state signal is the electron beam power transmitted through the knife edge, detecting that the electron beam power is the first and second percentages of the maximum electron beam power respectively, and corresponding to the distance L through which the electron beam scans; the second percentage is greater than the first percentage; the maximum electron beam power is the power when the electron beam is not shielded by the knife edge;
and in step S2, the beam spot diameter d of the electron beam is obtained by the following formula:
d＝ALsinθ；
wherein A is the proportionality coefficient of the distance L passed by the electron beam scanning under different electron beam powers and the electron beam diameter d.
6. The method for measuring the size of a gaussian distributed electron beam spot according to claim 5, wherein: the first percentage is 10% -20% and the second percentage is 80% -90%.
7. The method for measuring the beam spot size of a gaussian distributed electron beam according to any of claims 1 to 4, characterized in that: in step S1: the kerf is made by dicing a wafer and has an atomic level flatness.
8. The method for measuring the size of a gaussian distributed electron beam spot according to claim 7, wherein: the material of the wafer is silicon/gallium arsenide.
9. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, performs the steps of the method according to any one of claims 1-8.
10. A system for measuring the size of a gaussian distributed electron beam spot, comprising a memory and a processor connected to each other, said memory having stored thereon a computer program, characterized in that said computer program, when being executed by the processor, performs the steps of the method according to any of claims 1-8.
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| CN202311274279.8A Pending CN117373885A (en) | 2023-09-27 | 2023-09-27 | Method and system for measuring size of Gaussian distribution electron beam spot |
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| CN (1) | CN117373885A (en) |
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