WO2023197099A1

WO2023197099A1 - Particle corrector and particle system

Info

Publication number: WO2023197099A1
Application number: PCT/CN2022/086035
Authority: WO
Inventors: 马泽; 贺佳坤; 张文; 赵冲; 张超
Original assignee: 华为技术有限公司
Priority date: 2022-04-11
Filing date: 2022-04-11
Publication date: 2023-10-19

Abstract

A particle corrector and a particle system, which relate to the technical field of particles, and are used for solving the problems of the particle beam current being relatively low, the resolution being low, the particle beam quality being poor, etc. The particle corrector comprises: a first beam-splitting plate (31) and a correction plate assembly (32), wherein the first beam-splitting plate (31) is provided with M beam-splitting holes (311); and the correction plate assembly (32) comprises N correction plates (321, 322, 323), which are arranged in a stacked manner. Each correction plate (321, 322, 323) has M through holes (320) and M electrode assemblies; the M beam-splitting holes (311) are arranged corresponding to the M through holes (320) on a one-to-one basis; the M electrode assemblies are arranged corresponding to the M through holes (320) on a one-to-one basis; and each electrode assembly is used for generating, in the corresponding through hole (320), an electric field which is used for correcting a particle beam, wherein M is an integer greater than or equal to 1, and N is an integer greater than or equal to 1. In the particle corrector, the particle beam flow and the particle beam quality can be effectively improved; in addition, the flexibility and the application range of the particle corrector can be improved.

Description

A particle corrector and particle system

Technical field

The present application relates to the field of particle technology, and in particular to a particle straightener and a particle system.

Background technique

In particle systems, since the particles used (such as electrons, ions, etc.) have shorter wavelengths, when the particle system is applied to fields such as microscopy imaging, it can provide better resolution than traditional optical systems. In addition, the particle system can also be used in semiconductor process defect detection, mask inspection, electron beam exposure and other fields, and has good accuracy and resolution. In practical applications, due to the Coulomb repulsion between charged particles, blindly increasing the beam current in the charged particle beam to increase the throughput of the particle system will cause undesirable problems such as beam spot expansion and resolution reduction. . In addition, when there are multiple particle beams, the particle beam needs to be corrected by a particle corrector to improve the quality of the particle beam. However, the current particle corrector still has many shortcomings. For example, when the inclination angle of the particle beam changes at different locations, the current particle corrector cannot independently adjust the electric field at a certain location. Therefore, it cannot make targeted adjustments to the particle beam whose inclination angle changes, which has certain limitations. sex.

Contents of the invention

This application provides a particle straightener and a particle system that are beneficial to improving the particle beam current and ensuring the quality of the particle beam.

On the one hand, the present application provides a particle straightener, including: a first beam splitting plate and a straightening plate assembly. The first beam splitting plate has M beam splitting holes. The correction plate assembly includes N stacked correction plates. Each correction plate has M through holes and M electrode assemblies. The M beam splitting holes are arranged in one-to-one correspondence with the M through holes, and the M electrode assemblies are arranged in The through holes are arranged in one-to-one correspondence, and each electrode assembly is used to generate an electric field in the corresponding through hole for correcting the particle beam. Among them, M and N are integers greater than or equal to 1. In the particle corrector provided by the present application, the particle beam generated by the particle source can be separated into multiple independent particle beams. When multiple particle beams work simultaneously, the system throughput can be improved without sacrificing system resolution. Specifically, in order to improve the throughput of the system, the beam current of the particle beam generated by the particle source can be increased. Since the particle beam generated by the particle source is divided into multiple independent particle beams, in each particle beam, the Coulomb repulsion between charged particles is small, making it less likely to cause beam spot expansion, etc. Therefore, it can Ensure system resolution.

In some implementations, the particle corrector may also include a control circuit electrically connected to the M electrode assemblies for separately controlling the power supply of the M electrode assemblies to control the electric field formed in each through hole. Strength and direction. Since the control circuit can control the power supply of each electrode assembly separately, the intensity and direction of the electric field formed in each through hole can be differentially controlled, and at the same time, it can also increase the flexibility and application range of the particle straightener. . For example, when the inclination angle of a certain particle beam changes, the control circuit can control the power supply of the electrode assembly to adaptively correct the particle beam after the inclination angle changes by changing the intensity or direction of the electric field.

In specific implementation, the first beam splitting plate may be disposed at the front end of the correcting plate assembly, or may be disposed at the rear end of the correcting plate assembly. When the first beam splitting plate is disposed at the front end of the correcting plate assembly, the first beam splitting plate can effectively separate the initial particle beam generated by the particle source. Then, the correcting plate assembly can then separate the inclination, position and angle of each particle beam. Adjust parameters such as astigmatism. When the first beam splitting plate is arranged at the rear end of the correction plate assembly, the correction plate assembly can effectively separate the initial particle beam generated by the particle source and adjust the inclination, position, astigmatism and other parameters of each particle beam. . The first beam splitter can filter the corrected particle beam to ensure the quality of the final particle beam.

Of course, in practical applications, beam splitting plates can also be provided at both the front and rear ends of the correction plate assembly. For example, a first beam splitting plate can be provided at the front end of the correcting plate assembly, so that the initial particle beam can be divided into M particle beams. The second beam splitting plate can perform filtering and other processing on the particle beam corrected by the correction plate assembly to improve the quality of the final particle beam.

In specific settings, the structures of the first beam splitting plate and the second beam splitting plate may be exactly the same or different. In addition, the relative relationships between the beam splitting holes in the first beam splitting plate, the through holes in the correction plate assembly, and the beam splitting holes in the second beam splitting plate may be diverse.

For example, the beam splitting holes in the first beam splitting plate and the beam splitting holes in the second beam splitting plate have the same cross-sectional size, and the two beam splitting holes are coaxially arranged.

Alternatively, the cross section of the beam splitting hole in the first beam splitting plate may be larger than the cross section of the beam splitting hole in the second beam splitting plate. Specifically, the first beam splitting plate is used to separate the initial particle beam. The second beam splitter is used to filter the particle beam to filter out the part of the particle beam that is too close to the electrode, thereby effectively ensuring the quality of the particle beam. In addition, the fill factor of particle correctors can be increased. Among them, the fill factor refers to the ratio of the particle beam movement range to the diameter of the through hole.

Alternatively, the beam-splitting holes in the first beam-splitting plate and the beam-splitting holes in the second beam-splitting plate may also be disposed asynchronously.

Specifically, in the first beam splitting plate, the beam splitting hole may be shifted by a certain distance to the irradiation direction of the particle beam (the opposite direction of the oblique direction). When the particle beam passes through the beam splitting hole of the first beam splitting plate, it will have a certain offset during its downward propagation due to its certain inclination angle. Since the closer to the electrode, the uniformity of the electric field becomes worse, causing problems such as aberration of the particle beam. Therefore, after the beam splitting hole of the first beam splitting plate is offset by a certain distance toward the irradiation direction of the particle beam, the lateral offset distance of the particle beam in the through hole can be increased to reduce the adverse impact of the electrode on the particle beam. In addition, the fill factor of particle correctors can be increased.

It can be understood that in other embodiments, the cross-sectional sizes of the beam splitting holes of the first beam splitting plate and the beam splitting holes of the second beam splitting plate can be adaptively adjusted according to different needs. In addition, the beam-splitting hole in the first beam-splitting plate and the through-hole in the correction plate assembly may be arranged coaxially or non-axially. Correspondingly, the beam-splitting hole in the second beam-splitting plate and the through-hole in the correction plate assembly can be arranged coaxially or non-axially. No limitation is made here.

In addition, in each electrode assembly, multiple electrodes may be included, so that a more uniform and more directional electric field may be generated within the corresponding through hole.

In specific settings, multiple electrodes can be evenly distributed along the central axis of the through hole, or the position of each electrode can be adaptively adjusted according to different needs. It can be understood that during specific arrangement, the electrode is not limited to being arranged on the inner wall of the through hole, but can also be arranged at other positions near the through hole; that is, it only needs to ensure that the electrode assembly can generate an electric field in the corresponding through hole.

In addition, the control circuit can independently control the power supply of each electrode, so that parameters such as the direction and intensity of the electric field in each through hole can be accurately controlled. That is, through multiple electrodes and control circuits, an electric field in any direction can be generated in a direction perpendicular to the axis of the through hole (or it can also be understood that the direction of the electric field can rotate 360° in a plane perpendicular to the axis of the through hole), so , which can deflect and position the particle beam in any direction.

In specific implementation, in the direction perpendicular to the axis of the through hole, the cross section of the electrode may be square, rectangular, arcuate or trapezoidal. The shape, structure and arrangement position of the electrodes are not limited in this application.

On the other hand, this application also provides a particle system. Includes: particle source, collimating lens and particle corrector. The particle source is used to generate the initial particle beam; the collimating lens is used to collimate the initial particle beam so that the initial particle beam can be in a parallel or nearly parallel state when it reaches the particle corrector. The particle corrector is used to separate the initial particle beam to form multiple particle beams, and can adjust the inclination, offset, astigmatism and other parameters of each particle beam. When the particle beam converges on the sample, the sample can be imaged, detected, exposed and processed with higher precision.

In some implementations, in order to better focus the particle beam onto the sample, the particle system may also include a focusing lens. The focusing lens may include M groups of focusing units, and the M groups of focusing units are arranged in one-to-one correspondence with the M through holes. Each group of focusing units is used to focus the corresponding particle beam to effectively focus the particle beam on the sample. In addition, since each particle beam is focused by an independent focusing unit, each particle beam can be focused exclusively to improve the focusing effect and make the particle beam array more uniform. In addition, it can also prevent particle beams from crossing each other and avoid interaction between different particle beams.

Description of the drawings

Figure 1 is a schematic cross-sectional structural diagram of a particle system provided by an embodiment of the present application;

Figure 2 is a schematic cross-sectional structural diagram of another particle system provided by an embodiment of the present application;

Figure 3 is a schematic cross-sectional structural diagram of a particle corrector provided by an embodiment of the present application;

Figure 4 is a schematic plan view of a first correction plate provided by an embodiment of the present application;

Figure 5 is a partial planar structural schematic diagram of a first correction plate provided by an embodiment of the present application;

Figure 6 is a partial planar structural schematic diagram of a first correction plate provided by an embodiment of the present application;

Figure 7 is a schematic three-dimensional structural diagram of an electrode assembly provided by an embodiment of the present application;

Figure 8 is a schematic plan view of an electrode assembly provided by an embodiment of the present application;

Figure 9 is a schematic three-dimensional structural diagram of another electrode assembly provided by an embodiment of the present application;

Figure 10 is a schematic plan view of another electrode assembly provided by an embodiment of the present application;

Figure 11 is a schematic three-dimensional structural diagram of another electrode assembly provided by an embodiment of the present application;

Figure 12 is a schematic plan view of another electrode assembly provided by an embodiment of the present application;

Figure 13 is a schematic cross-sectional structural diagram of a particle corrector provided by an embodiment of the present application;

Figure 14 is a schematic cross-sectional structural diagram of another particle corrector provided by an embodiment of the present application;

Figure 15 is a schematic cross-sectional structural diagram of another particle corrector provided by an embodiment of the present application;

Figure 16 is a schematic cross-sectional structural diagram of another particle corrector provided by an embodiment of the present application;

Figure 17 is a schematic cross-sectional structural diagram of another particle straightener provided by an embodiment of the present application;

Figure 18 is a schematic cross-sectional structural diagram of a particle system provided by an embodiment of the present application.

Reference signs

01-sample; 10-particle source; 11-initial particle beam; 12-particle beam; 20-collimating lens; 30-particle corrector; 31-first beam splitting plate; 311-beam splitting hole; 32-correction plate Component; 320-through hole; 321-first correction plate; 322-second correction plate; 323-third correction plate; 324-fourth correction plate; 325-fifth correction plate; 326-sixth correction plate; 33 -The second beam splitting plate; 34-electrode; 331-beam splitting hole; 40-focusing lens; 41-focusing unit.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be described in further detail below in conjunction with the accompanying drawings.

In order to facilitate understanding of the particle corrector provided by the embodiment of the present application, its application scenarios are first introduced below.

The particle corrector provided by the embodiments of the present application can be applied in systems that need to adjust particle beams. It should be noted that, in order to facilitate understanding of the technical solution of the present application, the initial particle beam described below refers to a collection of particles generated by a particle source and not separated. A particle beam refers to a collection of particles after the initial particle beam is divided. Particles refer to negative electrons. Of course, in practical applications, the particles can also be charged particles such as ions.

As shown in Figure 1, take the particle system as an example. The particle system is based on particle beams to achieve its basic functions. It mainly includes a particle source 10, a collimating lens 20, a particle corrector 30 and a focusing lens 40. The particle source 10 is used to generate the initial particle beam 11; the collimating lens 20 is used to collimate the initial particle beam 11, so that the initial particle beam 11 can be in a parallel or nearly parallel state when it reaches the particle corrector 30. The particle corrector 30 is used to separate the initial particle beam 11 to form multiple (four are shown in the figure) particle beams 12, and can adjust the inclination, offset, astigmatism and other parameters of each particle beam 12. Make adjustments. Focusing lens 40 is used to focus the particle beam onto the sample. When the particle beam 12 converges on the sample 01, higher-precision imaging, detection, exposure and other processing can be performed on the sample 01.

For example, when particle systems are used in fields such as microscopy imaging, the wavelength of the particles is smaller than the wavelength of light waves. Therefore, microscopic imaging devices using particle systems (such as electron microscopes) can provide better resolution than optical microscopes and can observe more microscopic structures.

In addition, particle systems can also be used in fields such as quality inspection. For example, sample 01 can be a semiconductor device, a mask, and other types of entities. Particle beam 12 can detect sample 01.

In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

The terminology used in the following examples is for the purpose of describing specific embodiments only and is not intended to limit the application. As used in the specification and appended claims of this application, the singular expressions "a," "an," "the above," "the" and "the" are intended to also include, for example, "a or "plural" unless the context clearly indicates otherwise. It should also be understood that in the following embodiments of this application, "at least one" and "one or more" refer to one, two or more than two. The term "and/or" is used to describe the relationship between associated objects, indicating that there can be three relationships; for example, A and/or B can mean: A exists alone, A and B exist simultaneously, and B exists alone, Where A and B can be singular or plural. The character "/" generally indicates that the related objects are in an "or" relationship.

Reference in this specification to "one embodiment" or "some embodiments" or the like means that a particular feature, structure or characteristic described in connection with the embodiment is included in one or more embodiments of the application. Therefore, the phrases "in one embodiment", "in some embodiments", "in other embodiments", "in other embodiments", etc. appearing in different places in this specification are not necessarily References are made to the same embodiment, but rather to "one or more but not all embodiments" unless specifically stated otherwise. The terms “including,” “includes,” “having,” and variations thereof all mean “including but not limited to,” unless otherwise specifically emphasized.

As shown in Figure 2, in one embodiment provided by this application, the particle straightener 30 includes a first beam splitter plate 31, a straightening plate assembly 32 and a control circuit (not shown in the figure). The first beam splitting plate 31 has four beam splitting holes 311 , and the first beam splitting plate 31 is disposed at the front end of the correction plate assembly 32 . Wherein, the front end of the correction plate assembly 32 refers to the side of the correction plate assembly 32 that receives the particle beam 12 (the upper side in the figure); correspondingly, the rear end of the correction plate assembly 32 refers to the side where the correction plate assembly 32 transmits particles. One side of bundle 12 (lower side in the figure). After the initial particle beam 11 generated by the particle source 10 is collimated by the collimating lens 20 to the first beam splitting plate 31, part of the particles will be blocked by the first beam splitting plate 31, and other part of the particles can be transmitted through the plurality of beam splitting holes 311. , thereby being able to separate the initial particle beam 11 into four particle beams 12 . The four particle beams 12 transmitted from the four beam splitting holes 311 will propagate to the correction plate assembly 32 . In the embodiment provided in this application, the correction plate assembly 32 includes three stacked correction plates (such as corrector chips), which are a first correction plate 321, a second correction plate 322 and a third correction plate 323 respectively. Each correction plate has four through holes 320 , and the four through holes 320 of each correction plate correspond to the four beam splitting holes 311 of the first beam splitting plate 31 in one-to-one correspondence. Specifically, the four particle beams 12 emerge from the four beam splitting holes 311, pass through the through holes 320 of the first correction plate 321, the second correction plate 322, and the third correction plate 323 in sequence, and finally pass through the third correction plate 320. The four through holes 320 of the plate 323 are exposed respectively. In addition, each correction plate also includes four electrode assemblies (not shown in the figure), and each electrode assembly is used to generate an electric field in the corresponding through hole 320 . The control circuit is electrically connected to the electrode assembly and is used to control the power supply of each electrode assembly to control parameters such as electric field intensity and direction in each through hole 320 . When the particle beam 12 passes through the through hole 320, under the action of the electric field force, the inclination angle, displacement, astigmatism and other parameters of the particle beam 12 can be corrected, thereby improving the quality of the particle beam 12. In addition, since the initial particle beam 11 will be separated by the particle corrector 30, the throughput of the particle system can be effectively improved to ensure the performance of the particle system. Specifically, in order to improve the throughput of the particle system, the beam current of the initial particle beam 11 generated by the particle source 10 can be increased. Since the initial particle beam 11 generated by the particle source 10 is divided into a plurality of independent particle beams 12, in each particle beam 12, the Coulomb repulsion between the charged particles is small, making it less likely to cause beam spot expansion, etc. situation, therefore, is able to guarantee the resolution of the particle system.

In specific implementation, the first beam splitting plate 31 may be a metal plate such as a copper plate or an aluminum plate, or may be a plate-shaped structure made of other conductive materials. Alternatively, the first beam splitting plate 31 may also be an insulating plate whose surface is coated with conductive material. The conductive material may be coated on the upper surface of the first beam splitting plate 31 and the inner wall of the beam splitting hole 311 , or may be coated on all surfaces of the first beam splitting plate 31 . When charged particles (such as electrons) hit the first beam splitting plate 31 , the charges can be derived to prevent charges from accumulating on the first beam splitting plate 31 . In specific configuration, the first beam splitting plate 31 may be a circular plate, an elliptical plate, a rectangular plate or other shaped plate structures. The number of beam splitting holes 311 can be set according to different requirements. In summary, the number of beam splitting holes 311 may be M, where M is an integer greater than or equal to 1. For example, the number of beam splitting holes 311 may be one or more. The plurality of beam splitting holes 311 can be arranged in an annular array on the first beam splitting plate 31 , or can be arranged in a rectangular array or other relative positions.

It can be seen from Figure 2 that the initial particle beam 11 collimated by the collimating lens 20 is not completely parallel, but has a certain tilt angle (or diffusion angle), and the closer the initial particle beam 11 is to the edge , the greater the tilt angle. In specific applications, this tilt angle needs to be corrected, otherwise the particle beam 12 will seriously deviate from the optical axis. Among them, the four dotted lines in the figure respectively represent the optical axes of the four particle beams 12.

Please continue to see Figure 2. In the embodiment provided by this application, the first correction plate 321, the second correction plate 322 and the third correction plate 323 are arranged parallel to each other, and the four through holes 320 on each correction plate are respectively arranged coaxially. It can be understood that during specific implementation, the number of through holes 320 in each correction plate can be matched according to the number of beam splitting holes 311 in the first beam splitting plate 31 . To summarize, when the first beam splitting plate 31 includes M beam splitting holes 311, M through holes 320 are provided in the first correcting plate 321, the second correcting plate 322 and the third correcting plate 323, and M The beam splitting holes 311 and the 3*M through holes 320 are arranged in one-to-one correspondence. It should be noted that the one-to-one arrangement of the beam splitting holes 311 and the through holes 320 means that the corresponding beam splitting holes 311 and the through holes 320 are used to pass the same particle beam 12 . In addition, during specific setting, the number of correction plates included in the correction plate assembly 32 can also be set accordingly according to different needs. In summary, the correction plate assembly 32 may include N correction plates arranged in a stack, where N is an integer greater than or equal to 1. For example, the correction plate assembly 32 may include only one correction plate, or may include two or more correction plates.

Below, the correction process of the particle beam 12 will be described in detail, taking the correction plate assembly 32 including three correction plates as an example.

Please continue to see Figure 2. When adjusting the particle beam 12, the three correction plates can independently adjust the particle beam 12. Taking the leftmost particle beam 12 as an example, the particle beam 12 has an inclination angle to the left before being injected into the through hole 320 of the first correction plate 321 . When passing through the through hole 320, the electrode assembly on the first correction plate 321 can deflect the particle beam 12 to a nearly vertical state, so that the propagation direction of the particle beam 12 is parallel to the optical axis. In addition, before being corrected, the particle beam 12 has an inclination angle to the left during propagation; therefore, when the particle beam 12 propagates a certain distance, there is a certain deviation between its center and the optical axis. Therefore, the center of the particle beam 12 (which can also be understood as the spot position of the particle beam) needs to be adjusted. Specifically, when the particle beam 12 passes through the through hole 320 of the second correction plate 322, the electrode assembly on the second correction plate 322 can deflect the particle beam 12 to a state with a rightward tilt angle, so that the particle beam 12 propagates An offset to the right can be generated during the process. When the particle beam 12 passes through the through hole 320 of the third correction plate 323, the electrode assembly on the third correction plate 323 can deflect the particle beam 12 to a nearly vertical state. At this time, the propagation direction of the particle beam 12 is consistent with the optical axis. coincide. In summary, the inclination angle of the particle beam can be gradually adjusted through the first correction plate 321 , the second correction plate 322 and the third correction plate 323 so that the propagation direction of the particle beam 12 is parallel to the optical axis. In addition, the position of the particle beam 12 can also be adjusted by the self-propagation of the particle beam 12 so that the center of the particle beam 12 coincides with the optical axis.

In practical applications, when the particle beam 12 passes through the first beam splitting plate 321, since the particle beams 12 at different positions have different inclination angles, the inclination angle and position of each particle beam 12 need to be adjusted to varying degrees. adjust. For example, among the four particle beams 12 shown in FIG. 2 , the leftmost and rightmost particle beams 12 have larger inclination angles, and the two particle beams 12 have opposite inclination angles. The inclination angles of the two particle beams 12 located in the middle are smaller, and the inclination angles of the two particle beams 12 are opposite. Therefore, during specific implementation, when each particle beam 12 passes through the through hole 320 of the correction plate assembly 32, the electric field intensity and direction in each through hole 320 need to be adaptively adjusted so that each particle beam 12 is corrected. Finally, the parallel relationship can be maintained, and the distribution position of the particle beam 12 can be adjusted.

It can be understood that during specific implementation, the number of correction plates included in the correction plate assembly 32 can be flexibly increased or decreased according to actual needs. In addition, the deflection intensity and direction of the particle beam 12 by each correction plate can also be flexibly set.

For example, as shown in FIG. 3 , in another embodiment provided by this application, the correction plate assembly 32 includes six correction plates arranged in a stack. They are the first correction plate 321, the second correction plate 322, the third correction plate 323, the fourth correction plate 324, the fifth correction plate 325 and the sixth correction plate 326 respectively. Among them, the first correcting plate 321, the second correcting plate 322, the third correcting plate 323 and the fourth correcting plate 324 are used to generate a leftward electric field force to the particle beam 12, so as to gradually deflect the inclination angle of the particle beam 12 to the left. The fifth correcting plate 325 and the sixth correcting plate 326 are used to generate a rightward electric field force toward the particle beam 12 so as to gradually deflect the inclination angle of the particle beam 12 to the right. Finally, the center of the particle beam 12 coincides with the optical axis.

In the embodiment provided in this application, the control circuit can separately control the power supply of each electrode assembly, so that the intensity and direction of the electric field in each through hole 320 can be separately controlled to effectively improve the use of the particle corrector 30 Flexibility and scope of application. For example, when the beam current of the initial particle beam 11 generated by the particle source 10 changes, the inclination angle of each particle beam 12 may change differently. Specifically, when the inclination angle of a certain particle beam 12 changes, the control circuit can control the power supply of the electrode assembly to adaptively correct the particle beam after the inclination angle changes by changing the intensity or direction of the electric field. The power supply control of the electrode assembly by the control circuit includes but is not limited to: controlling the power supply and off state of the electrode assembly, the size of the electric field formed, the direction of the electric field, etc.

In specific implementations, each electrode assembly may include multiple electrodes, thereby generating a more uniform and more directional electric field.

For example, as shown in Figure 4. Taking the first correction plate 321 as an example, in one embodiment provided in this application, each electrode assembly may include eight electrodes 34 (one is marked in the figure), and the eight electrodes 34 are arranged on the periphery of the through hole 320 . In specific implementation, the eight electrodes 34 can be evenly distributed along the central axis of the through hole 320, or the position of each electrode 34 can be adaptively adjusted according to different needs. It can be understood that during specific arrangement, the electrode 34 is not limited to being arranged on the periphery of the through hole 320 , but can also be arranged on the inner wall of the through hole 320 or other locations near it; that is, it only needs to ensure that the electrode assembly can be positioned in the corresponding through hole 320 Just generate an electric field inside.

In addition, the control circuit can independently control the power supply of each electrode 34, so that parameters such as the direction and intensity of the electric field in each through hole 320 can be accurately controlled. That is, through the plurality of electrodes 34 and the control circuit, an electric field in any direction can be generated in a direction perpendicular to the axis of the through hole 320 (or it can also be understood that the direction of the electric field can be rotated 360° in a plane perpendicular to the axis of the through hole 320 ), therefore, the particle beam 12 can be deflected and positioned in any direction.

In a specific arrangement, the plane of the electrode assembly may be perpendicular to the central axis of the through hole 320 , so that an electric field perpendicular to the central axis of the through hole 320 can be generated in the through hole 320 .

For example, as shown in FIG. 5 , the electrode assembly includes eight electrodes 34 arranged in a circular array. The planes of the eight electrodes 34 are parallel to the surface of the first correction plate 321 . Specifically, the central axis of the through hole 320 is perpendicular to the surface of the first correction plate 321. Therefore, when the plane of the eight electrodes 34 is parallel to the surface of the first correction plate 321, the plane of the electrode assembly is Perpendicular to the central axis of the through hole 320 , an electric field perpendicular to the central axis of the through hole 320 can be generated in the through hole 320 . The plane of the electrode assembly may be any plane parallel to the first correction plate 321 . For example, the plane of the electrode assembly may coincide with any one of the surfaces of the first correction plate 321 , or may be the central symmetry plane of the two surfaces of the first correction plate 321 . When it is necessary to deflect the particle (electron) beam to a certain inclination angle in the first direction, the control circuit can pass a certain voltage to each electrode 34 to form a uniform electric field opposite to the first direction in the through hole 320, so that the particles Beam 12 is deflected in a first direction. The first direction refers to any direction perpendicular to the axis of the through hole 320 .

It can be understood that during specific implementation, the control circuit can flexibly control the energization state of each electrode 34 according to different requirements, which will not be described again here.

In addition, in the embodiment provided in this application, the astigmatism of the particle beam 12 can also be adjusted through the correction plate assembly 32 .

Specifically, as shown in Figure 6. In practical applications, the divergence angles of the particle beam 12 in the X direction and the Y direction may be different. If not corrected, the particle beam 12 will gradually deform into an elliptical shape. In addition, in the entire particle system, each component (such as the electromagnetic lens) has certain processing errors, and assembly errors may also occur during the assembly process of each component. These errors will also increase the astigmatism problem of the particle beam.

As shown in FIG. 6 , when the divergence angle of the particle beam 12 in the X direction is large and the divergence angle in the Y direction is small. The control circuit can pass a certain voltage to each electrode 34 to form a correction electric field, thereby correcting the astigmatism problem of the particle beam 12 . Among them, the X direction and the Y direction are only schematic directions, and during specific implementation, the angle between the X direction and the Y direction is not limited. That is, the particle corrector 30 provided by the embodiment of the present application can correct the divergence angle of the particle beam 12 in any direction.

It can be understood that during specific implementation, the number of electrodes included in each electrode assembly is not limited to the eight mentioned above. For example, each electrode assembly may include 2, 3, 4 or more electrodes, and the position arrangement of the multiple electrodes can be flexibly adjusted according to the actual situation, which is not limited in this application.

In addition, during specific installation, the shapes of the electrodes can also be diverse.

For example, as shown in FIG. 7 , in one embodiment provided by this application, the electrode 34 has an arc-shaped structure. Specifically, please refer to FIG. 8 . In the direction perpendicular to the central axis of the through hole, the cross-section of the electrode 34 is arc-shaped, and the inner arc surfaces of the eight electrodes 34 are all facing the axis of the through hole.

As shown in FIG. 9 , in another embodiment provided by this application, the electrode 34 has a rectangular block structure. Specifically, referring to FIG. 10 , the electrode 34 has a rectangular cross-section in a direction perpendicular to the central axis of the through hole.

As shown in FIG. 11 , in another embodiment provided by this application, the electrode 34 has a trapezoidal block structure. Specifically, referring to FIG. 12 , the electrode 34 has a trapezoidal cross-section in a direction perpendicular to the central axis of the through hole.

It can be understood that in other embodiments, the shape and structure of the electrode 34 can be flexibly set according to different situations, and this application is not limited thereto.

In addition, as shown in FIG. 13 , when the particle straightener 30 is specifically configured, in addition to the first beam splitting plate 31 and the straightening plate assembly 32 , it may also include a second beam splitting plate 33 .

Specifically, the second beam splitting plate 33 is located at the rear end (lower end in the figure) of the correction plate assembly 32 , and the second beam splitting plate 33 also has a beam splitting hole 331 . In specific settings, the structures of the first beam splitting plate 31 and the second beam splitting plate 33 may be identical or different. In addition, the relative relationships between the beam splitting holes 311 in the first beam splitting plate 31 , the through holes 320 in the correction plate assembly 32 , and the beam splitting holes 331 in the second beam splitting plate 33 may be diverse.

For example, as shown in Figure 13, in one embodiment provided by this application, the beam splitting hole 311 in the first beam splitting plate 31 and the beam splitting hole 331 in the second beam splitting plate 33 have the same cross-sectional size, and the two beam splitting holes 311 and 331 in the second beam splitting plate 33 have the same cross-sectional size. The beam splitting holes are coaxially arranged. The cross-sectional size of the beam splitting hole 311 refers to the area of the beam splitting hole 311; correspondingly, the cross-sectional size of the second beam splitting hole 331 refers to the area of the beam splitting hole 331, and the cross-sectional size of the through hole 320 refers to The area of the through hole 320.

It can be understood that in other embodiments, only one of the first beam splitting plate 31 and the second beam splitting plate 33 may be retained.

For example, as shown in FIG. 14 , in one embodiment provided by this application, only the first beam splitting plate 31 is retained and the second beam splitting plate 33 is cancelled. When processing the particle beam 12 , the first beam splitter plate 31 can separate the initial particle beam (not shown in the figure), and then the plurality of particle beams 12 are processed by the correction plate assembly 32 . Specifically, in the examples shown in FIGS. 13 and 14 , the particle beam 12 enters the through hole 320 from the position of the optical axis. Since the particle beam 12 has a certain inclination angle, during the downward propagation process will produce an offset to the right. In addition, since the closer to the inner wall of the through hole 320 is, the uniformity of the electric field becomes worse. Therefore, in order to ensure the quality of the particle beam 12 , there is a certain limit on the lateral offset of the particle beam 12 . Alternatively, the minimum size of the inner diameter of the through hole 320 is limited.

In addition, as shown in FIG. 15 , in some embodiments, only the second beam splitting plate 33 may be retained and the first beam splitting plate 31 may be eliminated. When processing the particle beam 12 , the correction plate assembly 32 may first separate the initial particle beam (not shown in the figure) and correct the particle beam 12 . During the processing, since the closer the position is to the electrode (or the inner wall of the through hole 320 ), the uniformity of the electric field becomes worse, which causes aberration and other undesirable problems in the particle beam 12 . Therefore, in order to obtain a higher quality particle beam 12 , the second beam splitting plate 33 can filter the particle beam 12 to transmit the area of the particle beam 12 away from the electrode and to transmit the area of the particle beam 12 close to the electrode. block. At the same time, it can also effectively improve the filling factor of the system.

In addition, as shown in FIG. 16 , when the particle corrector 30 includes a first beam splitting plate 31 and a second beam splitting plate 33 , the cross section of the beam splitting hole 311 in the first beam splitting plate 31 can also be larger than that of the second beam splitting plate. The cross section of the beam splitting hole 331 in 33.

Specifically, the beam splitting hole 311 in the first beam splitting plate 31 and the beam splitting hole 331 in the second beam splitting plate 33 are coaxially arranged. The first beam splitting plate 31 is used to separate the initial particle beam (not shown in the figure). The second beam splitting plate 33 is used to filter the particle beam 12 to filter out the part of the particle beam 12 that is too close to the electrode, thereby effectively ensuring the quality of the particle beam 12 . In addition, the filling factor of the particle straightener 30 can also be improved.

Alternatively, the beam splitting hole 311 in the first beam splitting plate 31 and the beam splitting hole 331 in the second beam splitting plate 33 may also be disposed asynchronously.

Specifically, as shown in FIG. 17 , in the first beam splitting plate 31 , the beam splitting hole 311 may be shifted by a certain distance toward the irradiation direction of the particle beam 311 (left direction in the figure). When the particle beam 12 passes through the beam splitting hole 311, it has a certain inclination angle, so it will shift to the right during its downward propagation. Since the uniformity of the electric field becomes worse at a position closer to the electrode (or the inner wall of the through hole 320 ), problems such as aberration may occur in the particle beam 12 . Therefore, after shifting the beam splitting hole 311 to the left by a certain distance, the lateral shifting distance of the particle beam 12 in the through hole 320 can be increased to reduce the adverse effects of the electrode on the particle beam 12 . In addition, the filling factor of the particle straightener 30 can also be improved. Specifically, in the examples shown in FIGS. 15 to 17 , the final particle beam 12 enters the through hole 320 from a position deviated from the optical axis (the left position in the figure), and this part of the particle beam 12 is located between the upper limit of displacement on the left and the upper limit of displacement on the right, and is eventually corrected back to the position of the optical axis. Therefore, the lateral offset of the particle beam 12 is increased. Alternatively, it is beneficial to reduce the minimum size of the inner diameter of the through hole 320 , and therefore, it is beneficial to increase the filling factor of the orthotic device 30 .

It can be understood that in other embodiments, the cross-sectional sizes of the beam splitting holes 311 of the first beam splitting plate 31 and the beam splitting holes 331 of the second beam splitting plate 33 can be adaptively adjusted according to different needs. In addition, the beam splitting hole 311 in the first beam splitting plate 31 and the through hole 320 in the correction plate assembly 32 may be arranged coaxially or not. Correspondingly, the beam splitting hole 331 in the second beam splitting plate 33 and the through hole 320 in the correction plate assembly 32 can be arranged coaxially or asynchronously. This application does not limit this.

In addition, as shown in Figure 18, embodiments of the present application also provide a particle system. It includes: particle source 10, collimating lens 20 and the above-mentioned particle corrector 30. The particle source 10 is used to generate the initial particle beam 11; the collimating lens 20 is used to collimate the initial particle beam 11, so that the initial particle beam 11 can be in a parallel or nearly parallel state when it reaches the particle corrector 30. The particle corrector 30 is used to separate the initial particle beam 11 to form multiple (four are shown in the figure) particle beams 12, and can adjust the inclination, offset, astigmatism and other parameters of each particle beam 12. Make adjustments. When the particle beam 12 converges on the sample 01, higher-precision imaging, detection, exposure and other processing can be performed on the sample 01.

In specific implementation, the collimating lens 20 may be an electromagnetic lens. The initial particle beam 11 can be focused or diverged through an electric field or a magnetic field, thereby achieving its collimating effect. In specific applications, the type and structure of the collimating lens are not limited in this application.

In addition, as shown in FIG. 18 , in order to better focus the particle beam 12 on the sample 01 , the particle system may also include a focusing lens 40 . The focusing lens 40 may include four groups of focusing units 41 , and each group of focusing units 41 is used to focus a single particle beam 12 so as to effectively focus the particle beam 12 on the sample 01 . In addition, since each particle beam 12 is focused by an independent focusing unit 41, each particle beam 12 can be focused exclusively to improve the focusing effect and make the array of particle beams 12 more uniform. In addition, it can also prevent particle beams 12 from crossing each other and avoid mutual influence between different particle beams 12 .

The above are only specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, and all of them should be covered. within the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

A particle corrector, which is characterized by including:

A first beam splitting plate, the first beam splitting plate has M beam splitting holes;

a correction plate assembly, arranged on one side of the first beam splitting plate;

The correction plate assembly includes N stacked correction plates, each of the correction plates has M through holes and M electrode assemblies, and the M beam splitting holes are arranged in one-to-one correspondence with the M through holes. And M electrode assemblies are arranged in one-to-one correspondence with M through holes; wherein, each electrode assembly is used to generate a correction electric field in the corresponding through hole;

Among them, M is an integer greater than or equal to 1, and N is an integer greater than or equal to 1.
The particle corrector according to claim 1, further comprising a control circuit electrically connected to the M electrode assemblies for separately controlling the power supply of the M electrode assemblies;

Wherein, the power supply control of the electrode assembly by the control circuit includes: controlling the power supply and off state of the electrode assembly, the size of the electric field formed, and the direction of the electric field.
The particle corrector according to claim 1 or 2, characterized in that the plane of the electrode assembly is perpendicular to the central axis of the through hole.
The particle corrector according to any one of claims 1 to 3, characterized in that the cross section of the beam splitting hole is smaller than the cross section of the through hole.
The particle corrector according to any one of claims 1 to 4, characterized in that the beam splitting hole on the first beam splitting plate is arranged non-axially with the corresponding through hole.
The particle corrector according to any one of claims 1 to 5, further comprising a second beam splitting plate, the second beam splitting plate being disposed on the correction plate assembly away from the first beam splitting plate. one side of the board;

The second beam splitting plate has M beam splitting holes, and the M beam splitting holes and the M through holes are arranged in one-to-one correspondence.
The particle corrector according to claim 6, wherein the first beam splitting plate is provided at the front end of the correction plate assembly, and the second beam splitting plate is provided at the rear end of the correction plate assembly;

Wherein, the front end of the correction plate assembly is the side from which the correction plate assembly receives the particle beam, and the rear end of the correction plate assembly is the side from which the correction plate assembly transmits the particle beam.
The particle corrector according to claim 6 or 7, characterized in that the beam splitting hole on the second beam splitting plate is coaxially arranged with the through hole.
The particle straightener according to any one of claims 6 to 8, characterized in that the cross-sectional size of the beam-splitting through hole of the first beam-splitting plate is greater than or equal to the cross-section of the beam-splitting hole of the second beam-splitting plate. size.
The particle corrector according to any one of claims 1 to 9, wherein each electrode assembly includes a plurality of electrodes, and the plurality of electrodes are arranged in an array around the axis of the through hole.
The particle corrector according to claim 10, characterized in that the control circuit is used to control the power supply of each electrode separately;

Wherein, the power supply control of the electrode by the control circuit includes: controlling the power supply and off state of the electrode and the size of the electric field formed.
The particle corrector according to claim 10 or 11, characterized in that in each of the electrode assemblies, a plurality of the electrodes are provided on the inner wall of the corresponding through hole.
The particle corrector according to claim 12, wherein in each of the electrode assemblies, a plurality of the electrodes are arranged in an annular array along the axis of the corresponding through hole.
The particle straightener according to any one of claims 1 to 13, characterized in that, in a direction perpendicular to the axis of the through hole, the cross-section of the electrode is square, rectangular, arc-shaped or trapezoidal.
A particle system, characterized in that it includes a particle source, a collimating lens and the particle corrector according to any one of claims 1 to 14, and the collimating lens is located between the particle source and the particle corrector. between.
The particle system according to claim 15, further comprising a focusing lens, the focusing lens including M groups of focusing units, and the M groups of focusing units are arranged in one-to-one correspondence with the M through holes.