Charged particle beam deflection electrostatic lens and charged particle beam deflection method

Abstract

The invention provides a charged particle beam deflection electrostatic lens and a charged particle beam deflection method. The charged particle beam deflection electrostatic lens comprises at least one on-axis electrode, an off-axis electrode and a power distribution module, through holes are formed in the on-axis electrode and the off-axis electrode, and charged particle beams pass through the through holes; the off-axis electrode is parallel to the on-axis electrode, the central axis of the off-axis electrode is not coaxial with a preset incident optical axis, and the central axis of the on-axis electrode is coaxial with the preset incident optical axis; the power distribution module is electrically connected with the on-axis electrode, the power distribution module is electrically connected with the off-axis electrode, and the power distribution module is used for configuring different potentials for the on-axis electrode and the off-axis electrode so as to form a non-axisymmetric electric field to enable the charged particle beam to deflect. The problems that in the prior art, the structure is complex, and charged particle beams cannot be deflected and focused at the same time are solved. According to the invention, the charged particle beams are deflected and focused simultaneously by adopting a simple structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of charged particle beam transmission, in particular to a charged particle beam deflection electrostatic lens and a charged particle beam deflection method. BACKGROUND

[0002] In the field of lithography, detection and imaging, it is an indispensable requirement to realize focusing and deflection of charged particle beam transmission. The methods for realizing deflection of charged particle beam transmission include electric deflection method and magnetic deflection method. The electric deflection method uses parallel electrodes to generate an electric field, and uses the electric field to deflect the charged particle beam. The deflection angle is controlled by adjusting the field strength direction of the deflection voltage. The magnetic deflection method uses electromagnetic coils to generate a magnetic field, and uses the Lorentz force to deflect the charged particle beam. The deflection angle is controlled by adjusting the current direction of the coil. With the integration of electronic devices, there is a higher requirement for the integration of charged particle beam transmission elements.

[0003] At present, the existing technology uses two independent electrostatic / magnetic lens devices to realize focusing and deflection of charged particle beam transmission, thereby realizing focusing and deflection respectively. However, in actual application, in addition to the control of the deflection angle of the charged particle beam, it is also necessary to simultaneously focus the charged particle beam. However, the complex device structure of the existing technology cannot simultaneously deflect and focus the charged particle beam. SUMMARY

[0004] In order to solve the above problems, the present application provides a charged particle beam deflection electrostatic lens and a charged particle beam deflection method, which realizes simultaneous deflection and focusing of the charged particle beam using a simple structure.

[0005] To achieve the above purpose, the embodiments of the present application provide a charged particle beam deflection electrostatic lens and a charged particle beam deflection method, which include at least one on-axis electrode, one off-axis electrode and a power distribution module. The on-axis electrode and the off-axis electrode are both provided with through holes for passing the charged particle beam. The off-axis electrode is parallel to the on-axis electrode, the center axis of the off-axis electrode is different from the preset incident optical axis, and the center axis of the on-axis electrode is coaxial with the preset incident optical axis. The power distribution module is electrically connected with the on-axis electrode and the off-axis electrode, and is used to configure different potentials for the on-axis electrode and the off-axis electrode to form a non-axisymmetric electric field to deflect the charged particle beam.

[0006] The embodiment of the present application provides a charged particle beam deflection electrostatic lens, which comprises an on-axis electrode with a central axis coaxial with a preset incident light axis and an off-axis electrode with a central axis non-coaxial with the preset incident light axis, different potentials are configured to the on-axis electrode and the off-axis electrode through a power distribution module, thereby forming a non-axisymmetric electric field, the charged particle beam is deflected under the influence of a non-equilibrium Coulomb force in the non-axisymmetric electric field, and the charged particle beam is focused while being deflected by combining the electric field generated by the at least one on-axis electrode, so that the charged particle beam is deflected and focused at the same time under the simple structure design.

[0007] Further, the through hole is arranged at the center of the on-axis electrode and the off-axis electrode, and the through hole can be arranged as an arbitrary rotational symmetry body.

[0008] Further, the central axis of the off-axis electrode deviates from the central axis of the on-axis electrode by a preset first distance value, and the preset first distance value is less than or equal to a preset second distance value, wherein the preset second distance value is set according to the aperture of the through hole of the off-axis electrode.

[0009] In the above scheme, the off-axis electrode deviates from the on-axis electrode by a preset first distance value, and in order to enable the charged particle beam to pass through the off-axis electrode, the preset first distance value is further limited to be less than or equal to the preset second distance value according to the through hole of the off-axis electrode, thereby providing a guarantee for subsequent realization of deflection and focusing of the charged particle beam at the same time.

[0010] Further, the on-axis electrode comprises one or more combinations of an incident side electrode, a focusing electrode and an exit side electrode; the incident side electrode, the focusing electrode and the exit side electrode are arranged side by side; and the central axis of the incident side electrode, the central axis of the focusing electrode and the central axis of the exit side electrode are coaxial.

[0011] In the above scheme, the incident side electrode, the focusing electrode and the exit side electrode are coaxially arranged side by side in one or more combinations, so that the electric field generated by the incident side electrode, the focusing electrode and the exit side electrode after power distribution of the power distribution module realizes focusing of the charged particle beam, thereby providing a guarantee for subsequent realization of deflection and focusing of the charged particle beam at the same time.

[0012] Further, the power distribution module is electrically connected with the incident side electrode, the focusing electrode and the exit side electrode; the power distribution module is configured to configure the incident side electrode and the exit side electrode with a first electric potential; the power distribution module is configured to configure the focusing electrode with a second electric potential; and the power distribution module is configured to configure the off-axis electrode with a third electric potential. Further, the first electric potential and the second electric potential form a first electric field region for focusing the charged particle beam. Further, the third electric potential and the first electric potential and / or the second electric potential form a second electric field region for deflecting the charged particle beam. Further, one or more combinations of the incident side electrode, the focusing electrode and the exit side electrode and the corresponding configured electric potentials form a focusing electrostatic lens for forming the first electric field region for focusing the charged particle beam; and one or more combinations of the off-axis electrode and the corresponding configured electric potential and the adjacent incident side electrode, focusing electrode and exit side electrode and the corresponding configured electric potentials form an off-axis electrostatic lens for forming the second electric field region for deflecting the charged particle beam.

[0013] In the above scheme, the power distribution module is configured to configure the incident side electrode and the exit side electrode with a first electric potential, the focusing electrode with a second electric potential and the off-axis electrode with a third electric potential, so that the first electric field region generated by the potential difference between one or more combinations of the incident side electrode, the exit side electrode and the focusing electrode realizes the focusing of the charged particle beam, and the second electric field region generated by the potential difference between the off-axis electrode and one or more combinations of the adjacent incident side electrode, exit side electrode and focusing electrode realizes the deflection of the charged particle beam, thereby realizing the simultaneous focusing and deflection of the charged particle beam.

[0014] Further, the on-axis electrode and the off-axis electrode can be set to any size and any shape.

[0015] Further, the charged particle beam includes an electron beam and an ion beam.

[0016] The embodiment of the present application also provides a charged particle beam deflection method, including: receiving a charged particle beam entering the through hole of the on-axis electrode along a preset incident optical axis; controlling the power distribution module to configure the on-axis electrode and the off-axis electrode with different electric potentials to generate a non-axisymmetric electric field; and controlling the charged particle beam to deflect based on the non-axisymmetric electric field.

[0017] The charged particle beam deflection method provided by the embodiment of the present application is used in the electrostatic lens structure in which at least one on-axis electrode with the central axis coaxial with the preset incident light axis and one off-axis electrode with the central axis non-coaxial with the preset incident light axis are arranged, and a power distribution module is used to configure different potentials for the on-axis electrode and the off-axis electrode, so as to form a non-axisymmetric electric field, and the charged particle beam is deflected under the influence of the non-equilibrium Coulomb force in the non-axisymmetric electric field, and the electric field generated by the at least one on-axis electrode itself is combined to focus the charged particle beam while deflection, so that the charged particle beam is deflected and focused at the same time under the simple structure design. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 An existing principle diagram of electron beam deflection is provided for an embodiment of the present application.

[0019] Figure 2 A working principle diagram of a charged particle beam deflection electrostatic lens is provided for an embodiment of the present application.

[0020] Figure 3 A structure diagram of a charged particle beam deflection electrostatic lens is provided for an embodiment of the present application. Figure 1

[0021] Figure 4 A structure diagram of a charged particle beam deflection electrostatic lens is provided for an embodiment of the present application. Figure 2

[0022] Figure 5 A structure diagram of a charged particle beam deflection electrostatic lens is provided for an embodiment of the present application. Figure 3

[0023] Figure 6 A structure diagram of a charged particle beam deflection electrostatic lens is provided for an embodiment of the present application. Figure 4

[0024] Figure 7 A simulation result diagram of a charged particle beam deflection electrostatic lens is provided for an embodiment of the present application.

[0025] Figure 8 A step flow diagram of a charged particle beam deflection method is provided for an embodiment of the present application. DETAILED DESCRIPTION

[0026] ​​​​The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] See also Figure 1 , Figure 1 A schematic diagram of the principle of an existing electron beam deflection provided in an embodiment of the present invention is shown as follows: Figure 1 As shown in FIG, one of the methods for realizing electron beam deflection by electric deflection in the prior art is to use a planar deflector, such as Figure 1 As shown in (A), the planar deflector 11 is composed of two parallel electrodes with opposite voltages (+V and -V) applied to them. An electric field is formed in the normal direction (x) of the electrodes. By changing the voltage, the electron beam is deflected in a single direction. Another method of achieving electron beam deflection using the electric deflection method in the prior art is to achieve this using a multi-pole deflector. Figure 1 As shown in (B), two planar deflectors 11 are arranged in a circle. Each planar deflector 11 is composed of two oppositely arranged electrodes. By applying appropriate voltages to the electrodes, charged particles can be deflected in two orthogonal directions (x and y).

[0028] Example 1

[0029] See also Figure 2 , Figure 2 A schematic diagram of the working principle of an electrostatic lens for deflecting a charged particle beam provided in one embodiment of the present invention; Figure 2 As shown, the electron beam e1 deviates from the optical axis g by a distance g0. Figure 2 The electrostatic focusing lens 21 shown is deflected by the unbalanced Coulomb force in the y-axis direction. The deflection angle θ1 depends on the off-axis distance y'0 and the strength of the electrostatic focusing lens 21. Based on this principle, embodiments of the present invention, based on the electrostatic focusing lens 21, provide an electrostatic lens for deflecting a charged particle beam, comprising: at least one on-axis electrode 31, an off-axis electrode 33, and a power distribution module; both the on-axis electrode 31 and the off-axis electrode 33 are provided with a through hole 32 for passing the charged particle beam. The off-axis electrode 33 is parallel to the on-axis electrode 31, and the central axis of the off-axis electrode 33 is not coaxial with the preset incident light axis a. The central axis of the on-axis electrode 31 is coaxial with the preset incident light axis a. The power distribution module is electrically connected to the on-axis electrode 31, and the power distribution module is electrically connected to the off-axis electrode 33. The power distribution module is used to configure different potentials for the on-axis electrode 31 and the off-axis electrode 33 to form a non-axisymmetric electric field, so that the charged particle beam is deflected by the unbalanced Coulomb force in the non-axisymmetric electric field.

[0030] A preferred scheme, the through hole 32 is arranged in the center of the on-axis electrode 31 and the off-axis electrode 33, the through hole 32 can be set as any rotational symmetry; the center axis of the off-axis electrode 33 deviates from the center axis of the on-axis electrode 31 by a preset first distance value, the preset first distance value is less than or equal to a preset second distance value, wherein the preset second distance value is set according to the aperture of the through hole 32 of the off-axis electrode 33. The on-axis electrode 31 comprises: one or more combinations of the incident side electrode 311, the focusing electrode 312 and the exit side electrode 313; the incident side electrode 311, the focusing electrode 312 (including the first focusing electrode 312a and the second focusing electrode 312b) and the exit side electrode 313 are arranged side by side; the center of the incident side electrode 311, the center of the focusing electrode 312 and the center of the exit side electrode 313 are coaxial. The power distribution module, comprising: the power distribution module is electrically connected with the incident side electrode 311, the power distribution module is electrically connected with the focusing electrode 312, and the power distribution module is electrically connected with the exit side electrode 313; the power distribution module is used for configuring the incident side electrode 311 and the exit side electrode 313 with a first electric potential; the power distribution module is used for configuring the focusing electrode 312 with a second electric potential; the power distribution module is used for configuring the off-axis electrode 33 with a third electric potential; the first electric potential and the second electric potential form a first electric field region, and the first electric field region is used for focusing the charged particle beam; the third electric potential and the first electric potential and / or the second electric potential form a second electric field region, and the second electric field region is used for deflecting the charged particle beam. One or more combinations of the incident side electrode 311, the focusing electrode 312 and the exit side electrode 313 and their corresponding configured electric potential constitute a focusing electrostatic lens, which is used to form a first electric field region to focus the charged particle beam; the off-axis electrode 33 and its corresponding configured electric potential and one or more combinations of the adjacent incident side electrode 311, focusing electrode 312 and exit side electrode 313 and their corresponding configured electric potential constitute an off-axis electrostatic lens, which is used to form a second electric field region to deflect the charged particle beam; in this embodiment, one or more combinations of the incident side electrode 311, the focusing electrode 312 and the exit side electrode 313 can be explained as: only the incident side electrode 311, only the focusing electrode 312, only the exit side electrode 313, the incident side electrode 311, the focusing electrode 312 and the exit side electrode 313 in pairs, the incident side electrode 311, the focusing electrode 312 and the exit side electrode 313 exist at the same time and so on; the charged particle beam includes: electron beam and ion beam. The on-axis electrode 31 and the off-axis electrode 33 can be set to any size and any shape, for example: thin film electrode, electrode plate and electrode cylinder, etc., wherein the thin film electrode is very thin, the thickness is negligible; the electrode plate has a certain thickness; the thickness of the electrode cylinder is much larger than the aperture; in this embodiment, the electrode plate is preferred, so the electrode plate is taken as an example for explanation, which will not be repeated hereinafter.

[0031] As an example of one of the embodiments, see Figure 3 , Figure 3A schematic diagram of the structure of an electrostatic lens for deflecting a charged particle beam provided in one embodiment of the present invention Figure 1 .like Figure 3 As shown, in this embodiment, the charged particle beam deflection electrostatic lens is provided with five electrodes, including an on-axis electrode 31 consisting of an incident side electrode 311, two focusing electrodes 312 and an exit side electrode 313, wherein the focusing electrode 312 includes: a first focusing electrode 312a and a second focusing electrode 312b and an off-axis electrode 33, and is arranged in the order of the incident side electrode 311, the first focusing electrode 312a, the off-axis electrode 33, the second focusing electrode 312b and the exit side electrode 313. Both the on-axis electrode 31 and the off-axis electrode 33 are provided with through-holes 32. In this embodiment, the through-holes 32 include a first through-hole 321, a second through-hole 322a, a third through-hole 322b, a fourth through-hole 323, and a fifth through-hole 324. The first through-hole 321 is provided on the incident-side electrode 311, the second through-hole 322a is provided on the first focusing electrode 312a, the third through-hole 322b is provided on the second focusing electrode 312b, the fourth through-hole 323 is provided on the off-axis electrode 33, and the fifth through-hole 324 is provided on the exit-side electrode 313. In this embodiment, the through-holes 32 are preferably cylindrical. The incident-side electrode 311, the first focusing electrode 312a, the second focusing electrode 312b, the exit-side electrode 313, and the off-axis electrode 33 are preferably implemented using electrode plates of uniform size and shape.

[0032] The incident side electrode 311, the first focusing electrode 312a, the second focusing electrode 312b and the exit side electrode 313 are coaxially arranged side by side along the preset incident light axis a, that is, the central axes of the incident side electrode 311, the first focusing electrode 312a, the second focusing electrode 312b and the exit side electrode 313 are coaxial; the central axis a1 of the off-axis electrode 33 is set with an off-axis offset y0 (equivalent to a preset first distance value) relative to the preset incident light axis a, and the y0 value is set to be no more than one tenth of the aperture of the fourth through hole 323 (equivalent to a preset second distance value) to prevent some charged particles in the charged particle beam from failing to pass through the fourth through hole 323.

[0033] An additional power supply module (omitted in the figure) is provided to supply voltages to the on-axis electrode 31 and the off-axis electrode 33. The power supply module is configured to supply the same first voltage V1 to the incident-side electrode 311 and the exit-side electrode 313, to supply the same second voltage V2 to the first focusing electrode 312a and the second focusing electrode 312b, and to supply a third voltage V3 to the off-axis electrode 33. In the example of the embodiment, the incident-side electrode 311, the exit-side electrode 313, the first focusing electrode 312a, and the second focusing electrode 312b, together with the first voltage V1 and the second voltage V2 configured to the respective electrodes, form a focusing electrostatic lens to form a first electric field region, denoted as AR1; the first focusing electrode 312a, the second focusing electrode 312b, and the off-axis electrode 33, together with the second voltage V2 and the third voltage V3 configured to the respective electrodes, form an off-axis electrostatic lens to form a second electric field region, denoted as AR2; the first electric field region AR1 is used for focusing of the charged particle beam, and the second electric field region AR2 is a non-axisymmetric electric field and is used for deflection of the charged particle beam.

[0034] As another example of an implementation of the embodiment, see Figure 4 , Figure 4 A structure of a charged particle beam deflection electrostatic lens according to an embodiment of the application Figure 2 . As shown in Figure 4 , in the embodiment, the charged particle beam deflection electrostatic lens is provided with four electrodes, including the on-axis electrode 31 composed of the incident-side electrode 311, the focusing electrode 312, and the exit-side electrode 313, and the off-axis electrode 33, and arranged in the order of the incident-side electrode 311, the focusing electrode 312, the off-axis electrode 33, and the exit-side electrode 313. The on-axis electrode 31 and the off-axis electrode 33 are each provided with a through hole 32; in the embodiment, the through hole 32 includes a first through hole 321, a sixth through hole 322, a fourth through hole 323, and a fifth through hole 324, wherein the first through hole 321 is provided on the incident-side electrode 311, the sixth through hole 322 is provided on the focusing electrode 312, the fourth through hole 323 is provided on the off-axis electrode 33, and the fifth through hole 324 is provided on the exit-side electrode 313; in the embodiment, the through hole 32 is preferably cylindrical. The incident-side electrode 311, the focusing electrode 312, the exit-side electrode 313, and the off-axis electrode 33 are preferably implemented by electrode plates of the same size and shape.

[0035] The incident-side electrode 311, the focusing electrode 312, and the exit-side electrode 313 are coaxially arranged side by side along a preset incident optical axis a, that is, the central axes of the incident-side electrode 311, the focusing electrode 312, and the exit-side electrode 313 are coaxial; the central axis a1 of the off-axis electrode 33 is arranged to be off-axis relative to the preset incident optical axis a by y0 (equivalent to a preset first distance value), and the value of y0 is set to be not greater than one-tenth of the aperture of the fourth through hole 323 (equivalent to a preset second distance value), so as to prevent part of the charged particle beam from being unable to pass through the fourth through hole 323.

[0036] An additional power distribution module (omitted in the figure) is additionally arranged to provide voltages for the on-axis electrode 31 and the off-axis electrode 33, the power distribution module is configured with the same first potential V1 for the incident-side electrode 311 and the exit-side electrode 313, the power distribution module is configured with a second potential V2 for the focusing electrode 312, and the power distribution module is configured with a third potential V3 for the off-axis electrode 33; in order to distinguish from other embodiment examples, in the embodiment example, the incident-side electrode 311, the exit-side electrode 313, and the focusing electrode 312 and the first potential V1 and the second potential V2 correspondingly configured for each electrode form an electric field region of a focusing electrostatic lens, which is recorded as a third electric field region AR3; the focusing electrode 312 and the off-axis electrode 33 and the second potential V2 and the third potential V3 correspondingly configured for each electrode form an electric field region of an off-axis electrostatic lens, which is recorded as a fourth electric field region AR4, wherein the third electric field region AR3 is used for focusing of the charged particle beam, and the fourth electric field region AR4 is a non-axisymmetric electric field and is used for deflection of the charged particle beam. It is worth mentioning that, in order to distinguish from other embodiment examples, the first electric field region formed by the focusing electrostatic lens and the second electric field region formed by the off-axis electrostatic lens are recorded as the third electric field region AR3 and the fourth electric field region AR4 respectively for distinction, which is only used for explanation and illustration in the embodiment example and is not limited in any way.

[0037] As another embodiment of the embodiment, referring to Figure 5 , Figure 5 A structure diagram of a charged particle beam deflection electrostatic lens provided for an embodiment of the present application Figure 3 . As Figure 5As shown, in the embodiment, the charged particle beam deflection electrostatic lens is provided with three electrodes, including an on-axis electrode 31 composed of an incident-side electrode 311 and an exit-side electrode 313, and an off-axis electrode 33, and arranged in the order of the incident-side electrode 311, the off-axis electrode 33, and the exit-side electrode 313. The on-axis electrode 31 and the off-axis electrode 33 are each provided with a through hole 32, and in the embodiment, the through hole 32 includes a first through hole 321, a fourth through hole 323, and a fifth through hole 324, wherein the first through hole 321 is arranged on the incident-side electrode 311, the fourth through hole 323 is arranged on the off-axis electrode 33, and the fifth through hole 324 is arranged on the exit-side electrode 313; and in the embodiment, the through hole 32 is preferably cylindrical. The incident-side electrode 311, the exit-side electrode 313, and the off-axis electrode 33 are preferably implemented by electrode plates with uniform sizes and shapes.

[0038] The incident-side electrode 311 and the exit-side electrode 313 are coaxially arranged side by side along the preset incident optical axis a, i.e., the central axes of the incident-side electrode 311 and the exit-side electrode 313 are coaxial; and the central axis a1 of the off-axis electrode 33 is arranged off-axis relative to the preset incident optical axis a by y0 (equivalent to a preset first distance value), and the value of y0 is set to be not greater than one-tenth of the aperture of the fourth through hole 323 (equivalent to a preset second distance value), so as to prevent part of the charged particle beam from being unable to pass through the fourth through hole 323.

[0039] An additional power distribution module (omitted in the figure) is additionally arranged to provide voltages for the on-axis electrode 31 and the off-axis electrode 33, the power distribution module is configured with the same first potential V1 for the incident-side electrode 311 and the exit-side electrode 313, and the power distribution module is configured with a third potential V3 for the off-axis electrode 33, and the incident-side electrode 311, the exit-side electrode 313, and the off-axis electrode 33 form a coincident electric field region with the first potential V1 and the third potential V3 configured for each electrode, i.e., in the case where the charged particle beam deflection electrostatic lens is provided with three electrodes in the embodiment, the focusing electrostatic lens and the off-axis electrostatic lens composed of each electrode and the potential configured therefor are coincident, and the first electric field region and the second electric field region formed thereby are coincident; in order to distinguish from other embodiments, the coincident first electric field region and the second electric field region are recorded as a fifth electric field region AR5 in the embodiment, the fifth electric field region AR5 is used for focusing of the charged particle beam, and at the same time, the fifth electric field region AR5 is a non-axisymmetric electric field and is also used for deflection of the charged particle beam. It is worth mentioning that the coincident first electric field region and the second electric field region are recorded as the fifth electric field region AR5 for the purpose of distinction, and in the embodiment, the recording is only for explanation and does not have any limitation.

[0040] As another embodiment of the embodiment, see Figure 6 , Figure 6A schematic diagram of the structure of an electrostatic lens for deflecting a charged particle beam provided in one embodiment of the present invention Figure 3 .like Figure 6 As shown, in this embodiment, the charged particle beam deflection electrostatic lens is provided with two electrodes, including an on-axis electrode 31 formed by an incident-side electrode 311 and an off-axis electrode 33, which are arranged in the order of the incident-side electrode 311 and the off-axis electrode 33. Both the on-axis electrode 31 and the off-axis electrode 33 are provided with through-holes 32. In this embodiment, the through-holes 32 include: a first through-hole 321 and a fourth through-hole 323, wherein the first through-hole 321 is provided on the incident-side electrode 311 and the fourth through-hole 323 is provided on the off-axis electrode 33. In this embodiment, the through-holes 32 are preferably cylindrical. Preferably, the incident-side electrode 311 and the off-axis electrode 33 are both implemented using electrode plates of uniform size and shape.

[0041] The incident side electrode 311 is coaxially arranged along the preset incident light axis a, and the center axis a1 of the off-axis electrode 33 is set with an off-axis offset y0 (equivalent to the preset first distance value) relative to the preset incident light axis a. The y0 value is set to be no more than one tenth of the aperture of the fourth through hole 323 (equivalent to the preset second distance value) to prevent some charged particles in the charged particle beam from failing to pass through the fourth through hole 323.

[0042] An additional power distribution module (omitted in the figure) is provided to provide voltage to the on-axis electrode 31 and the off-axis electrode 33. The power distribution module configures a first potential V1 for the incident side electrode 311, and configures a third potential V3 for the off-axis electrode 33. The incident side electrode 311 and the off-axis electrode 33 form an overlapping electric field region with the first potential V1 and the third potential V3 configured corresponding to each electrode. That is, in the example of this embodiment, when the charged particle beam deflection electrostatic lens is provided with two electrodes, the focusing electrostatic lens and the off-axis electrostatic lens composed of each electrode and its configured potential overlap, and the first electric field region and the second electric field region formed overlap; in order to distinguish it from other examples, the overlapping first electric field region and the second electric field region are recorded as the sixth electric field region AR6 in the example of this embodiment. The sixth electric field region AR6 is used for focusing the charged particle beam. At the same time, the sixth electric field region AR6 is a non-axisymmetric electric field and is also used for deflecting the charged particle beam. It is worth mentioning that, in order to distinguish from other embodiments, the overlapping first electric field region and second electric field region are recorded as the sixth electric field region AR6 for distinction, which is only used for explanation in this embodiment and does not impose any limitation.

[0043] In order to further verify the use effect of the charged particle beam deflection electrostatic lens provided in the embodiment of the present application, the charged particle beam deflection electrostatic lens provided in the embodiment of the present application is simulated in the embodiment, and the charged particle beam deflection electrostatic lens composed of five electrodes is taken as an example for explanation. The simulation parameters are set as follows: the electron beam e is parallelly incident from the left side of the optical axis a, the initial energy of the electron beam is 5 kV, and the initial beam spot diameter is 0.24 mm; the thicknesses of the on-axis electrode 31 and the off-axis electrode 33 are both 0.6 mm and the shapes are consistent, the diameters of the through holes 32 of the electrodes are all 0.6 mm, and the interval between the electrodes is 0.8 mm; the center axis a1 of the off-axis electrode 33 is offset from the optical axis a by y0 of 0.06 mm, the first electric potential V1 applied to the incident side electrode 311 and the exit side electrode 313 is 0 V, the second electric potential V2 applied to the first focusing electrode 312a and the second focusing electrode 312b is 4000 V, and the third electric potential V3 applied to the off-axis electrode 33 is 3800 V. According to the simulation parameters, the simulation experiment is performed, and the simulation result is shown in Figure 7 , Figure 7 FIG. 2 is a simulation result diagram of the charged particle beam deflection electrostatic lens provided in the embodiment of the present application; as shown in FIG. 2, p is an equipotential line, i.e., a potential distribution, e is an electron beam, and the trajectory of the electron beam is described in the figure. It can be seen from the simulation result that the potential distribution near the fourth through hole 323 of the off-axis electrode 33 is a non-axisymmetric distribution, i.e., a non-axisymmetric electric field is formed. The electron beam e is deflected under the action of the non-axisymmetric electric field (equivalent to a deflection electric field), and the deflection angle θ is 8 mrad. The electron beam e is obviously focused during the deflection process, and the beam spot diameter after the focusing is only 5 um. It can be seen that the charged particle beam deflection electrostatic lens provided in the embodiment of the present application realizes the deflection and focusing of the charged particle beam at the same time under the simple structure design. Figure 7

[0044] The embodiment of the present application provides a charged particle beam deflection electrostatic lens, which comprises an on-axis electrode 31 and an off-axis electrode 33. The on-axis electrode 31 is provided with at least one through hole 32, and the center of the on-axis electrode 31 coincides with a preset incident optical axis a. The off-axis electrode 33 is provided with at least one through hole 32, and the center of the off-axis electrode 33 does not coincide with the preset incident optical axis a. A power supply module is configured to apply different electric potentials to the on-axis electrode 31 and the off-axis electrode 33, so as to form a non-axisymmetric electric field. The charged particle beam is injected from the through holes 32 of the on-axis electrode 31 and the off-axis electrode 33, and is deflected in the non-axisymmetric electric field. The on-axis electrode 31 itself generates an electric field, so that the charged particle beam is focused while being deflected. Thus, the deflection and focusing of the charged particle beam are realized at the same time under the simple structure design.

[0045] Embodiment 2

[0046] See Figure 8 , Figure 8 ​A schematic diagram of a step flow of a charged particle beam deflection method is provided for an embodiment of the present application. Figure 8 As shown in the figure, the embodiment of the present application also provides a charged particle beam deflection method, including steps S1 to S3, and the specific steps are as follows:

[0047] S1: receiving a charged particle beam incident along a preset optical axis from an incident side electrode;

[0048] S2: controlling a power distribution module to configure different potentials for the on-axis electrode and the off-axis electrode to generate a non-axisymmetric electric field;

[0049] S3: controlling the charged particle beam to deflect based on the non-axisymmetric electric field.

[0050] The charged particle beam deflection method provided by the embodiment of the present application, in the electrostatic lens structure of setting at least one on-axis electrode with the central axis of the electrode coaxial with the preset incident optical axis and setting one off-axis electrode with the central axis of the electrode different from the preset incident optical axis, controls the power distribution module to configure different potentials for the on-axis electrode and the off-axis electrode, thereby forming a non-axisymmetric electric field, so that the charged particle beam deflects in the non-axisymmetric electric field, and the charged particle beam is focused at the same time by combining the electric field generated by the at least one on-axis electrode itself, thereby achieving the deflection and focusing of the charged particle beam at the same time under the simple structure design.

[0051] The above description is only the preferred embodiment of the present application, and it should be pointed out that for those skilled in the art, without departing from the technical principles of the present application, a number of improvements and modifications can be made, and these improvements and modifications should also be considered as the protection scope of the present application.

[0052] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in the present application and the features of the different embodiments or examples without contradiction.

[0053] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

Claims

1. An electrostatic lens for deflecting a charged particle beam, characterized in that: include: At least one on-axis electrode, one off-axis electrode and a power distribution module; the on-axis electrode and the off-axis electrode are both provided with through holes, the through holes being used to pass a charged particle beam; The off-axis electrode is parallel to the on-axis electrode, the central axis of the off-axis electrode is not coaxial with the preset incident light axis, and the central axis of the on-axis electrode is coaxial with the preset incident light axis; The power distribution module is electrically connected to the on-axis electrode and the off-axis electrode, and is used to configure different potentials for the on-axis electrode and the off-axis electrode to form a non-axisymmetric electric field to deflect the charged particle beam.

2. The charged particle beam deflection electrostatic lens according to claim 1, characterized in that: The through hole is arranged at the center of the on-axis electrode and the off-axis electrode, and the through hole can be arranged as any rotationally symmetrical body.

3. The charged particle beam deflection electrostatic lens according to claim 2, characterized in that: The center axis of the off-axis electrode deviates from the center axis of the on-axis electrode by a preset first distance value, and the preset first distance value is less than or equal to a preset second distance value, wherein the preset second distance value is set according to the aperture of the through hole of the off-axis electrode.

4. The charged particle beam deflection electrostatic lens according to any one of claims 1 to 3, characterized in that: The on-axis electrode includes: one or more combinations of an incident side electrode, a focusing electrode and an exit side electrode; the incident side electrode, the focusing electrode and the exit side electrode are arranged side by side; the central axis of the incident side electrode, the central axis of the focusing electrode and the central axis of the exit side electrode are all coaxial.

5. The charged particle beam deflection electrostatic lens according to claim 4, characterized in that: The power distribution module includes: the power distribution module is electrically connected to the incident side electrode, the power distribution module is electrically connected to the focusing electrode, and the power distribution module is electrically connected to the exit side electrode; The power distribution module is used to configure a first potential for the incident-side electrode and the exit-side electrode; The power distribution module is used to configure a second potential for the focusing electrode; The power distribution module is used to configure a third potential for the off-axis electrode.

6. The charged particle beam deflection electrostatic lens according to claim 5, characterized in that: The first potential and the second potential form a first electric field region, and the first electric field region is used to focus the charged particle beam.

7. The charged particle beam deflection electrostatic lens according to claim 6, characterized in that: The third potential and the first potential and / or the second potential form a second electric field region, and the second electric field region is used to deflect the charged particle beam.

8. The charged particle beam deflection electrostatic lens according to claim 7, characterized in that: One or more combinations of the incident-side electrode, the focusing electrode, and the exit-side electrode and their corresponding configuration potentials constitute a focusing electrostatic lens, wherein the focusing electrostatic lens is used to form the first electric field region to focus the charged particle beam; The off-axis electrode and its corresponding configuration potential and one or more combinations of the adjacent incident side electrode, the focusing electrode and the exit side electrode and their corresponding configuration potentials constitute an off-axis electrostatic lens, which is used to form the second electric field region to deflect the charged particle beam.

9. The charged particle beam deflection electrostatic lens according to claim 1, characterized in that: The on-axis electrode and the off-axis electrode can be configured to have any size and any shape.

10. A charged particle beam deflection method, characterized in that: An electrostatic lens for deflecting a charged particle beam as claimed in any one of claims 1 to 9, comprising: receiving a charged particle beam incident from an incident-side electrode along a preset optical axis; Controlling the power distribution module to configure different potentials for the on-axis electrode and the off-axis electrode to generate a non-axisymmetric electric field; Based on the non-axisymmetric electric field, the charged particle beam is controlled to be deflected.

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